Cardio-Vascular Cases

Case 1a

Evaluation of the cardiac shadow is one of the very important element in the interpretation of plain chest radiography. In the plain radiographic technique, the heart shadow has only water density contents, blood and the myocardial tissues, all having a very comparable density. Hence, unless the density has changed, either by calcification or presence abundant fat or air, no specific information can be obtained on plain radiography. Looking broadly at the aspect of cardiac assessment, there are two essential components that can contribute for interpretation: 

1. change in the volume – as evidenced by increased dimensions 

2. changes manifested in the cardiac contours

The first element of increase in the volume is translated into single dimensional measurement, namely increase in the transverse cardiac size. Cardiothoracic ratio (CTR) is thus devised, which compares maximum cardiac dimension on either side of the midline to the maximum internal thoracic dimension. Cardiac shadow tends to be a little bulky in infants with a cardiothoracic ratio of up to 60%. In infants, cardiothoracic ratio can be measured either at the level of lateral angle of the eighth ribs or at the level of maximal internal thoracic diameter. Diaphragmatic positions do not significantly affect the cardiothoracic ratio. Subsequently during adolescence, CTR remains close to the adult values of 50% and below.

Obviously the contour changes can be modified by adjacent structures like the thymus and lungs. In children, the thymic shadow may contribute greatly to the cardio-thymic contour, sometimes by a massive proportion. The illustration above shows a likely thymic component to the cardiothoracic outline in frontal and lateral views.

Beyond the cardiac shadow, the lungs provide a window regarding cardiac hemodynamics. Pulmonary artery and vein provide information regarding high or low flow status (pulmonary arterial shadows) and back pressure effects if any (pulmonary veins). Pleural fluid could be a manifestation of cardiac failure. Finally, skeletal anomalies could be part of a congenital heart disease. Noting aortic (indentation of tracheal air column) and visceral position provides insight into cardiac development.

Case 1b

Moving on to the contour changes, an illustration is provided here to show what constitute various cardiac borders on plain radiography. Localised changes of the contours in these regions likely represent abnormalities of the border forming structures and effect of contibuting elements.  Note the components of the right cardiac border and the left cardiac border labelled in the diagram. Various patterns of chamber enlargement are also highlighted in the illustration. Each chamber has a specific pattern of expansion.

One more important element in the evaluation is the position of various cardiac valves. It will help identify any valve calcification. Usually, an aortic or mitral valve tends to show calcification. Identification of the valves are much more unambiguous in the lateral view. Aortic valve lies above the plane connecting the carinal point to the anterior costophrenic angle. Mitral valve lies behind. Implanted valve position also can be inferred by the expected valve position.

Case 1c

Various patterns of chamber enlargement is highlighted in the illustration. Each chamber has a specific pattern of expansion. Right atrial cardiac expansion mainly manifests as bulging of the right contour. Left atrium displays circumferential expansion on either side of the cardiac contour, causing widening of the carinal angle. Typical description of left atrial enlargement is a double contour of the right side of the heart. Enlarged left atrial appendage straightens the left cardiac border, projecting below the main pulmonary artery. Please note the ventricular expansion in frontal and lateral views. Also note that the right ventricular enlargement is more obvious in the lateral view, by way of encroachment of the retrosternal space. Left ventricular enlargement confirms to the expected clinical pattern (Downward and lateral expansion). 

All this information should be used as a template for making systematic observations regarding altered cardiac anatomy. Note that this anatomical description is valid for a normally developed heart. Complex heart disease does not follow this pattern all the time.

Imaging anatomy:

Morphological anatomy of the heart needs to be translated in to flexible imaging planes by manipulation of isotropic multidetector computed tomography (MDCT) or magnetic resonance imaging (MRI) volumetric datasets. Improvement in the temporal resolution of CT image acquisition has made it possible to obtain artifact free, phase specific, accurate datasets which can be subsequently utilized for image reconstruction. On the other hand MR techniques allow real-time flexible image planes along with structural analysis. This understanding of antomy has become a necessity for image interpretation.In this discussion only those landmarks which are visible or relevant for imaging study are highlighted for chamber localization and defining anomalies.. Anatomical landmarks of right atrium (RA) are the opening of coronary sinuses, superior vena cava and inferior vena cava. Crista terminalis which separates smooth and trabeculated components of right atrium is visible as liner ridge of varying thickness. Right atrial appendage is seen as pyramidal projection anterior to SVC.(upper Images) Right ventricle is triangular in shape, trabeculated in outline and has a moderator band at apical region, which transmits conduction fibers. Wall of right ventricle (RV) is relatively thinner compared to normal left ventricular wall. Right ventricular outflow is smooth. A muscular ridge, crista supra-ventricularis, separates tricuspid valve and RV outflow. Left ventricle (LV) on the other hand has a smooth outline, is thick walled and elliptical in shape. Left atrium (LA) receives pulmonary veins, superior and two inferior. Also finger shaped projection of anterio-superior aspect of LA characteristically identifies tubular atrial appendage.(Middle images) Normally pulmonary artery is antero-lateral (right) to aorta with aorta crossing from left to right. In majority right coronary artery arises from anteriorly located right aortic sinus and left coronary from left sinus. Coronary anomalies may be associated with congenital intra-cardiac malformations. Localization of normal and anomalous coronaries has direct implication in surgical management of cardiac disease. 

Study Protocol

Patients are pre-medicated with either Tab. Metaprolol orally or Tab. Diltiazem (in asthmatics) along with Tab. Alprazolam 0.25 mg to maintain heart rate between 60-70 bpm and reduce the anxiety. Scans are performed using 128-300 slice multidetector scanner and a dual flow injector. Retrospective ECG triggering is used. Non-contrast scan is first acquired to assess calcium score of coronary arteries in those patients with suspected/ diagnosed coronary artery disease. Calcium score is not done for patients with suspected/ diagnosed congenital heart disease.  Iohexol (Omnipaque 350 mgI/ml) is injected in the dose of 1-1.5 ml/kg and flow rate of 5.5 ml/sec followed by saline chase. Bolus track method is used for triggering with ROI at ascending aorta and threshold of 120 HU. Images are reconstructed with slice thickness of 0.6-0.7 mm. Images are reconstructed on a workstation (Philips workstation or Philips Intellispace or equivalent) to generate multiple phases, 3D (volume rendering) and curved planar reconstruction (CPR) images. CAD-RADS classification was used for reporting coronary artery disease in those patients with suspected/ diagnosed coronary artery disease.

(prepared in collaboration with Dr Shamim H)

CORONARY ARTERY ANATOMY

The right and left coronary arteries originate from the right and left sinuses of Valsalva of the aortic root, respectively. The posterior sinus rarely gives rise to a coronary artery and is referred to as the “noncoronary sinus.” The locations of the sinuses are anatomic misnomers: The right sinus is actually anterior in location and the left sinus is posterior. The myocardial distribution of the coronary arteries is somewhat variable, but the right coronary artery (RCA) almost always supplies the right ventricle (RV), and the left coronary artery (LCA) supplies the anterior portion of the ventricular septum and anterior wall of the left ventricle (LV). The vessels that supply the remainder of the LV vary depending on the coronary dominance.

Case 3: Right cornary artery

Right coronary artery anatomy

The RCA arises from the right coronary sinus somewhat inferior to the origin of the LCA. After its origin from the aorta, the RCA passes to the right of and posterior to the pulmonary artery and then emerges from under the right atrial appendage to travel in the anterior (right) atrioventricular (AV) groove (Figs. 1 and 2). In about half of the cases, the conus branch is the first branch of the RCA (Fig. 2). In the other half, the conus branch has an origin that is separate from the aorta. The conus branch always courses anteriorly to supply the pulmonary outflow tract. Occasionally, the conus branch can be a branch of the LCA (Fig. 3), may have a common origin with the RCA, or have dual or multiple branches.

In 55% of cases, the sinoatrial nodal artery (Figs. 4  and 5) is the next branch of the RCA, arising within a few millimeters of the RCA origin. In the remaining 45% of cases, the sinoatrial nodal artery arises from the proximal left circumflex (LCX) artery (Figs.6). In either case, the sinoatrial nodal artery always courses toward the superior  vena cava inflow near the cephalad aspect of the interatrial septum. As the RCA travels within the anterior AV groove, it courses downward toward the posterior (inferior) interventricular septum. As it does this, the RCA gives off branches that supply the  RV myocardium; these branches are called “RV marginals” or “acute marginals” (Fig. 7, 8). They supply the RV anterior wall. After it gives off the RV marginals, the RCA continues around the perimeter of the right heart in the anterior AV groove and courses toward the diaphragmatic aspect of the heart.

(prepared in collaboration with Dr Shamim H)

Coronary Dominance

The artery that supplies the posterior descending artery (PDA) and the posterolateral branch determines the coronary dominance. If the PDA and PLB arise from the RCA, then the system is said to be right dominant (80–85% of cases) (Figs. 3 and 4). In this instance, the RCA supplies the inferoseptal and inferior segments of the LV. If the PDA and PLB arise from the LCx artery, then the system is said to be left dominant (15–20% of cases) (Figs. 1 and 2). In this instance, the LCA supplies the inferoseptal and inferior segments of the LV. If the PDA comes from the RCA and the PLB comes from the LCx artery, the system is co-dominant (about 5% of cases) (Fig. 5). In left-dominant and co-dominant systems, the LCx artery continues in the posterior AV groove as the left AV groove artery and gives rise to left PLB. In left dominance, the PDA is the final branch of the AV groove artery. The distal RCA divides into the PDA and PLB in a right-dominant system. The non dominant system is usually noticeably smaller in calibre than the dominant system. This difference in caliber can be used as an additional clue to determine whether the coronary anatomy is right or left dominant. Usually arising just distal to the origin of the PDA, the AV nodal artery  can be recognized by its direct vertical course off of the distal RCA. In cases of left dominance, the AV node branch has a  similar appearance and location, but it arises just proximal to the PDA.

(prepared in collaboration with Dr Shamim H)

Case 5: Left coronary artery

LCA Anatomy

The LCA normally emerges from the left coronary sinus as the left main (LM) coronary artery (Fig. 1). The LM coronary artery is short (5–10 mm), passes to the left of and posterior to the pulmonary trunk, and bifurcates into the left anterior descending (LAD) and LCx arteries (Fig. 1,2 and 3). Occasionally, the LM coronary artery trifurcates into the LAD artery, the LCx artery, and the ramus intermedius artery (Fig. 2 and 3).

LAD Artery

The LAD artery (Fig 4.) runs in the anterior interventricular sulcus along the ventricular septum. Commonly, the LAD artery may be embedded within the anterior myocardium forming an overlying myocardial bridge (Fig 4.). Myocardial bridging is seen more often on CT than described in the coronary angiography literature. Most myocardial bridges are asymptomatic, although rarely myocardial bridging can be associated with ischemia. The LAD artery has branches called “septal perforators” (Fig. 1) that supply the anterior ventricular septum. It also has diagonal arteries (Fig. 4 and 6) that course over and supply the anterior wall of the LV. The diagonals and septal perforators are numbered sequentially from proximal to distal (i.e., D1, D2, S1, S2).

LCx Artery

The LCx artery (Figs.1) runs in the posterior AV groove analogous to the course of the RCA on the opposite side. The major branches of the LCx artery consist of obtuse marginals (OMs) (Figs. 1). OM branches supply the lateral wall of the LV. They are numbered sequentially from proximal to distal (i.e., OM1, OM2, OM3).

(prepared in collaboration with Dr Shamim H)

Case 6 : Coronary normal variations

NORMAL VARIANTS

Inferior wall supply

Beside the variability in the origin of the PDA, there is a spectrum of normal variants regarding the vascular supply to the inferior wall. There could be multiple branches, in which case the PDA is very small and multiple branches from the distal RCA, LCX and obtuse marginal branches supply the inferior wall. When the PDA has a premature takeoff and then courses toward the cardiac apex along the diaphragmatic surface of the RV, the variant is called early takeoff of the PDA. Finally, the LAD may wrap around the cardiac apex and supply a part of the apical inferior wall, known as a “wraparound LAD”.

Atrioventricular nodal supply

Small branches from the dominant artery typically supply the atrioventricular node. These branches arise in most of the cases from the distal RCA, as right dominance is the most common.

Sinoatrial nodal supply

Typically a single sinoatrial nodal branch supplies the sinoatrial node and it can arise from the proximal RCA (60% of the cases), from the proximal LCX or from the distal RCA or LCX artery (unusual).

Ramus intermedius

In this normal variant, the LMCA can trifurcate into a LAD, a LCX and a ramus intermedius. The ramus intermedius typically supplies the lateral and inferior walls, acting as a diagonal or obtuse marginal branch, while the arteries that usually supply this territory are small or absent.

Separate origin of the conus branch

In some patients the conus branch may arise directly from the aorta instead of arising from the proximal RCA.

Myocardial bridging (Fig)

Normally the coronary arteries are surrounded by the epicardial fat, but in some cases a coronary artery may travel intramyocardially for a variable length. A muscular or myocardial bridge is defined as an atypical course of a coronary artery in which it dips intramyocardially with resulting compression of the vessel during systole. The prevalence of this anomaly has a wide range from 0.15%-25% angiographically, to between 5% and 86% at autopsy. However, many reports from angiography may underestimate the prevalence of this anomaly, as recent studies with computed tomography (CT) have shown that myocardial bridging can be found in up to 25% of patients. In most of the cases the coronary involved was the proximal LAD, but it can occur in any segment. The myocardial bridging usually has a length that ranges from 10 mm to 50 mm. Most patients with myocardial bridging are asymptomatic and no abnormalities are observed during functional stress testing.

 An 11-year follow-up study underlined the benign prognosis of this normal variant as none of the patients developed myocardial ischaemia and it was demonstrated that the prognosis is independent of the severity of systolic narrowing of the lumen. However, this has since been debated and it has been shown that in rare instances myocardial bridging may be related to atypical angina, particularly if the segment is long or deep. Indeed, a study from Morales et al underlined that there is clinical evidence supporting the notion that, under certain conditions, systolic compression of an intramural LAD may impair coronary flow and precipitate myocardial ischaemia. The frequency of asymptomatic patients may seem surprising given that angiographic data show up to 50% systolic narrowing of the bridging artery, but it can be explained by the fact that most of the coronary blood flow occurs during diastole. Several studies showed that delayed diastolic reopening of the artery compressed during systole was at the basis for impaired coronary flow during diastole, decreased blood flow to the endocardium and a significant decrease in the vasodilator reserve and myocardial oxygen consumption. Ferreira et al studied 50 cases of myocardial bridges and underlined the important distinction between superficial and deep muscle bridges in producing ischaemia.

Acute take-off of LCX

Angelini et al defined this coronary anomaly in patients with an angle ≤ 45º between LMCA and LCX, in the left anterior oblique/caudal and/or right anterior oblique/caudal angiography X-ray projections. The origin and length of LMCA may be a relevant factor in this variant, as the acute take-off of the LCX may be caused by a usual distal point of origin so the LCX assumes a backward proximal course in order to join the normal distal LCX. This anatomic variant has an incidence around 2% and may be relevant in relation to the technical difficulties that can complicate angiographic procedures on the LCX.

(prepared in collaboration with Dr Shamim H)

High take-off

High take-off is defined as origin of a coronary artery more than 1 cm above the sinotubular junction . This variant has no inherent hemodynamic consequences, but catheterization of a coronary artery with a high origin may be difficult. In addition, preoperative identification of a high-origin coronary artery is important in patients undergoing aortotomy as part of aortic valve surgery or ascending aortic replacement. Cross-clamping of the aorta below a high-origin coronary artery may result in unsuccessful induction of cardioplegia. High origin of the RCA (Fig) is reported much more often in the literature than high origin of the LMCA. The former variant is also reported with increased frequency in with a bicuspid aortic valve. As a result, several case reports have been published describing incidental detection of a high-origin RCA in patients with a bicuspid aortic valve undergoing valve replacement. The importance of screening patients with a bicuspid aortic valve for a high origin RCA has been emphasized in the surgery literature.

(prepared in collaboration with Dr Shamim H)

Case 8

This patient with the angina on exertion is the lead case to explore the potential for CT coronary angiography for evaluation of coronary vascular disease. The Gold standard for the demonstration of coronary vascular occlusion is a conventional catheter radiography. This is the time tested method of direct injection of contrast into the coronaries through preformed coronary catheters, and recording the cine angio. Sones and Judkins catheters were very popular in the past for selective catheterisation of the coronaries. Coronary angiography explores and demonstrates the luminal changes. Luminal narrowing is one component of the disease, caused by intimal plaques of varying size, configuration and composition. CT angiography adds a further dimension to the cause of coronary narrowing by characterising the plaque, exploring the extent and studying remodelling of the adjacent vessels.

 Coronary disease can be quantified visually, by objective measurements either directly or with the extensive use of softwares. This patient is evaluated with an advanced software which provides information about extent, length of narrowing in relation to the long axis of the vessels from origin to the demonstrated termination. For the ease of assessment volumetric views, planar longitudinal views, cross sections, secondary vessel oriented reconstructions are provided. There is an interactive interface for flexible assessment. Typically narrowing is categorised as 

1. Not present(0), 

2. minor or Non obstructive(0-49%), and 

3.  potentially obstructive(50% and above)[moderate (50-69%) and severe (more than 70%)] 

To be relevant to patient management, narrowing has to be correlated with clinical symptoms and secondary myocardial changes. Combination of static and the stress imaging is recommended for more precise assessment of significance of narrowing for myocardial viability. Our patinet had appr. 40% narrowing of proximal LAD. Rest of the coronary arteries were normal. Calcium score was '0'. Thus patient comes under minor disease/ non-obstructive category.

Regarding the role of CT in symptomatic patients, in a  recent study,  following observations are made.  “ This prospective study found that almost half of patients clinically referred for catheter angio(ICA) after an abnormal nuclear MPI and clinical symptoms demonstrated no potentially obstructive lesions on CCTA. In this setting of patients of higher CAD risk, CCTA had high sensitivity (100%), specificity (84%) and negative predictive value (100%) for obstructive CAD and can thus be considered as a gatekeeper for ICA in this patient population.”[ Meinel, F.G., Schoepf, U.J., Townsend, J.C. et al. Diagnostic yield and accuracy of coronary CT angiography after abnormal nuclear myocardial perfusion imaging. Sci Rep 8, 9228 (2018). https://doi.org/10.1038/s41598-018-27347-8]

CAD-RADS  (Coronary Artery Disease - Reporting and Data System)

The use of coronary CTA to assess patients with stable chest pain in the outpatient setting or acute chest pain presenting to the Emergency Department has been validated in various clinical trials. Major guidelines are incorporating the use of coronary CT angiography as appropriate for assessing low to intermediate risk patients presenting with chest pain. Decreasing the variation in reporting is one aspect that will contribute to wider dissemination in clinical practice, minimize error and to ultimately improve patient outcome. The main goal of the CAD-RADS classification system is to propose a reporting structure that provides consistent categories for final assessment, along with suggestions for further management. In addition, CAD-RADS will provide a framework of standardization that may benefit education, research, peer-review and quality assurance with the potential to ultimately result in improved quality of care.

Degree of maximal coronary stenosis. Interpretation  Further Cardiac Investigation

CAD-RADS 0 :  0% (No plaque or stenosis); Documented absence of coronary artery disease; None

CAD-RADS 1 : 1 to 24% - Minimal stenosis or plaque with no stenosis. Minimal non-obstructive coronary artery disease; None

CAD-RADS 2 :; 25 to 49% ;Mild stenosis; Mild non-obstructive coronary artery disease; None

CAD-RADS 3 :50 to 69% stenosis Moderate stenosis ;Consider functional assessment

CAD-RADS 4 A- 70 to 99% stenosis or B - Left main >50% or 3- vessel obstructive (≥70%) disease; Severe stenosis [A: Consider invasive coronary angiography or functional assessment; B: invasive coronary angiography is recommended ]

CAD-RADS 5 : 100% (total occlusion);Total coronary occlusion; Consider invasive coronary angiography and/or viability assessment

CAD-RADS N : Non-diagnostic study;Obstructive coronary artery disease cannot be excluded. Additional or alternative evaluation may be needed

CAD-RADS reporting and data system for patients presenting with stable chest pain.

The CAD-RADS classification should be applied on a per-patient basis for the clinically most relevant (usually highest-grade) stenosis.

 All vessels greater than 1.5 mm in diameter should be graded for stenosis severity. CAD-RADS will not apply for smaller vessels (<1.5 mm in diameter).

MODIFIERS: If more than one modifier is present, the symbol “/” (slash) should follow each modifier in the following order: First: modifier N (non-diagnostic) Second: modifier S (stent) and Third: modifier G (graft) Fourth: modifier V (vulnerability).

 Coronary artery calcium score

(prepared in collaboration with Dr Shamim H)

Young female with a cardiac murmur suspected on echo to have a vascular anomaly. (a) Contrast axial CT demonstrate enlarged tortuous circumflex coronary artery( open arrow). (b) Axial image at a slightly level show circumflex arterial branches extending to SVC with luminal opacification, (white arrow) due to fistulous connection

Coronary anomalies:

Congenital coronary artery fistula (CAF) is a rare anomaly of anomalous termination either into a cardiac chamber, the coronary sinus, the superior vena cava, or the pulmonary artery or pulmonary vein. It is frequently demonstrated with the use of MDCT angiography can be seen up to 1 in 250.. CAFs are associated with left-right shunt are clinically significant when quantity of shunt is large. Shunt leads to myocardial steal phenomenon, may culminate in myocardial ischemia, angina, infarction or arrhythmia. Proximal coronary arteries are likely site of origin of fistula. The right coronary artery (RCA) is the most commonly involved (50–55%) followed by the left anterior descending coronary artery (LAD) (35–42%) Rarely circumflex coronary artery[Figure] or both coronary systems are simultaneously involved. Involved artery is enlarged and tortuous, may have aneurysms. Artery either drains in to a chamber or in to coronary vein. Significant numbers of patients (20–45%) with CAF have other congenital heart anomalies, such as TOF, ASD, VSD, PDA and pulmonary atresia with intact ventricular septum. Percutaneous transcatheter closure is recommended for patients with proximal fistula, fistula with a single drainage site and for surgically high risk older patients. Occlusion can be achieved by coils, umbrella devices, detachable balloons, vascular plugs, and covered stents. 

(prepared in collaboration with Dr Shamim H)

 Case 11

This case illustrates an another interesting condition ,ideally suited for CT detection, namely Anomalous origin of the left coronary artery (ALCAPA) In this condition left coronary artery arises from the pulmonary artery, which subsequently contribute to a right-to-left shunt and enlargement of the feeding the right coronary artery and the draining left coronary artery. There are infantile type and adult types.  Infantile type leads to myocardial infarction and death due to insufficient septal collaterals. Condition is managed by surgical correction. MR imaging by virtue of its ability to assess myocardial viability can help prognosticating the need for surgical repair

Case 12

Diagnosis of vascular anomalies of the aorta provides an opportunity to study the embryology of the aortic arch. In the provided images you are able to see right and left aortic arches (incomplete double aortic arch). Aortic arch is seen up to the origin of left subclavian artery. No continuity is shown beyond. Origins of the great vessels from the arch appear normal. This is a case of double aortic arch with distal interruption. Sometimes the condition is fully compensated by good collateral circulation, reconstituting distal aortic lumen. Patients tend to be symptomatic due to airway or esophageal compression.

(Prepared in colloboration with Dr Hemanth)

Case 13

3-year-old child, operated for a ventricular septal defect.

Contrast-enhanced axial images of the upper mediastinum and additional 3D reconstructions are provided (old collection). Do you have an observation or diagnosis? Those who are familiar with the anatomy of the upper mediastinum will notice that there is a right aortic arch and there is an abnormal vessel from the distal arch crossing over to the left side. This is an aberrant left subclavian artery in the right arch. Also note that the patient has a dilated pulmonary artery and some post-op changes in the sternum. Present 3D reconstructions provide much more smoother images. I was very proud of this great 3D rendering during the time of the examination (done in the 90’s), obtained after a long struggle in the workstation.

Case 14

7-year-old with the exertional dyspnoea.

Basis of interpretation of the chest radiograph for cardiac disease is illustrated in the examples presented earlier. Information described earlier should make some observations easier to detect.  What do you think the likely situation is? Observations of importance are: cardiomegaly, dilated main pulmonary artery, and increased pulmonary arterial markings. No atrial enlargement is obvious on the radiograph. It is very important to know whether patient is acyanotic or cyanotic. This is a case of a left-to-right shunt. In this case it was a secondum atrial septal defect, shown in the subsequent axial CT scan. Note that there is enlargement of the right atrium and ventricle, anterior to chambers. Atrial septal defect is outlined with an arrow.

Case 15: Chest x-ray with a pacemaker.

A fairly common radiography request in a patient with a cardiac pacemaker. Pacemakers (PM) can be of single-lead or dual-lead variety. Generally, a radiograph is requested to see the position and integrity of the electrode leads. Occasionally, leads penetrate through the myocardium and may be located outside the expected position. Breakage of the lead is another possible complication. In a dual lead PM, one lead is located in the right atrium and other in the apical part of the right ventricle. Lateral view is generally not performed. In this case, the chest X ray shows the respective locations of the two leads.

Case 16

Child evaluated for chest infection.

Any observation on this chest radiograph? Lungs appear clear. How about the vasculature? Perhaps difficult to evaluate; looks somewhat reduced. Any other observations? You should make note the right aortic arch, as shown by a localised impression on the tracheal air column. This may be part of a complex heart disease or an isolated observation. Also note that visceral situs is normal.

Case 17: Child with a suspected cardiac disease.

Two radiographs are provided, a day apart - the one on the right is a follow-up study. There is cardiomegaly showing globular cardiac enlargement. This patient had myocarditis. Examination is shown as a straight forward, typical pattern of pulmonary oedema, ‘bats-wing’ distribution of pulmonary fluid. Note that the findings are reversed following diuretics in a short span of time.

Case 18

Contrast-enhanced examination of the aorta in coronal and sagittal plane is available. Observations are not very difficult. What do you think is the cause for a serrated appearance of the distal abdominal aorta? If you are working in a tertiary centre with vascular surgery services, you will immediately notice that this is an aortic graft. Evaluation of vascular structures for graft planning, graft selection, positioning are part of the radiologist's job. Thorough understanding of the needs of the technique is mandatory. Modern radiology workstations are provided with a dedicated software for surgical planning. Also note the incidental observations in the spine and right femoral head..

Case 19

This is a classical case wherein observations and conclusions can be comfortably made. Sternotomy sutures indicate previous thoracic-cardiac surgery, information that is already provided. Note is made regarding the right jugular catheter. What about the cardiac state? If you are familiar with special cardiac configuration, the contour on the left side provides some clue. There is a phrase called the ‘Third Mughal’, basically explaining 3 layers of hierarchy. In this case the aortic knuckle, main pulmonary artery and the left atrial appendage form the 3 bulges. This points to the possibility of mitral stenosis with an enlarged left atrium and PAH. Search should not stop at this stage. What additional information is available? On careful scrutiny, you will note a dense calcification within the cardiac silhouette, representing calcified mitral valve apparatus. This information is valuable to the surgeon, although the significance of such an observation has become less relevant in the present day.

Case 20

50-year-old male with abdominal pain, pulsatile swelling in the mid abdomen.

Scanogram and the contrast enhanced images obtained at arterial and late phase are provided. Identification of the abnormality in this case is not very difficult. However, the diagnosis is challenging. What you are noticing is an extremely intensely enhancing lobulated lesion in the midline, extending predominantly to the left side. Aorta and vena cava are not separately seen. What is interesting is that there is a layered appearance of the wall along the anterior and the left posterolateral aspect, best shown on delayed images. This can be an abdominal aneurysm. Morphology is not that of a typical fusiform abdominal aneurysm, so you need to think of other possibilities like a mycotic aneurysm. Indeed, this patient had a mycotic aneurysm with a contained leak.

(Case prepared in collaboration with Dr. Vinay Belval.)

Case 21: Chest radiograph of a child with a limb deformity.

Case 21

Chest radiograph of a child with a limb deformity.

Abnormality is obvious, left upper limb is represented by a deformed soft tissue containing some bony elements. What is the significance of this kind of lesion in a child? If you are a syndrome-oriented radiologist, you will immediately recall Holt Oram syndrome. Abnormality of the radial ray and thumb are classic features of the syndrome, seen in association with congenital heart disease like septal defects. A variety of bone defects can be present from bony fusion to absence of bone development. It is an autosomal dominant disease with mutation in the TBX5 gene. These days, the abnormality may be detected antenatally.

Did you note the high position of the scapula like a Sprengel’s shoulder? Did you see that there is no shoulder joint? How about the rib abnormalities? I guess you have observed the poorly developed pectoral soft tissues and dilated main pulmonary artery segment. Patient likely has a septal defect.

Case prepared in collaboration with Dr Vinay Belval.)

Case 22

A  65-year-old patient underwent CABG. This is a post surgery follow-up radiographic examination.

Generally there are many extraneous devices placed on the patient during the postoperative period. You are familiar with the endotracheal tube, jugular venous catheters, cardiac electrodes, pacing wires etc. What do you think about a linear radiolucency along the left paraspinal region? Is it pulmonary or extrapulmonary? Is it a pocket of air in mediastinum (pneumomediastinum)? All these questions will not arise if you are familiar with this device, which is an intra-aortic balloon pump (IABP). We can note the radio-opaque tip of the catheter. It is placed within the aorta to provide mechanical support to the cardiac output.

Case 23

50-year-old female with dyspnoea on exertion, palpitation.

With some exposure to the interpretation of plain radiography, you can guess the likely diagnosis. Observation should be that there is a definite LV cardiomegaly, left atrial enlargement and signs of mild pulmonary venous congestion. What is the likely abnormality leading to these findings? Mitral valve disease should cross your mind. Is it mitral stenosis/mitral regurgitation/any other disease? Isolated mitral stenosis is usually associated with a small left ventricle. In this case the left ventricle certainly enlarged. This patient is likely to have mitral stenosis and regurgitation or coexisting Aortic valve disease also likely.

Case 24

This young patient, 2-month-old diagnosed to have congenital cardiac anomaly. Pre- and post-operative chest radiographs are provided.

Some clinical context is provided for you to guess, on radiography, the likely procedure performed on this patient. Do have any clue what procedure was done and in what clinical context? In fact, no specific diagnosis is possible on plain film alone, except for noting a large cardiac shadow. However, on post-surgical radiograph, you might make many observations. One major observation is the surgical clips on the left side of the mediastinum. This patient had a repair of a coarctation. Did you notice that there is osteotomy involving the ribs? Of course you might have noted some atelectasis in the right upper lobe which is a fairly common post-operative complication.

Case 25

45-year-old male patient with lower limb weakness and fatigability.

Coronal, sagittal and 3D reconstructions of the abdominal pelvic aorta are provided.

Diagnosis of vascular abnormalities are generally straightforward. Most of the occlusive vascular disease present with reduction in vessel caliber, irregularity of lumen, focal wall thickening and calcification. By and large, atherosclerosis is the most common etiology. Other etiological possibilities like aorto-arteritis, Takayasu disease, and giant cell arteritis can be considered in a specific context. In severe chronic stenosis, collateral circulation is generally well established. Collateral vessels can be shown by imaging. This patient had a diagnosis of aorto-arteritis.

Case 26

30-year-old male with high blood pressure.

This plain chest radiograph shows left ventricular cardiomegaly. Lung fields appear unremarkable. Any other observations? This is a young patient with obvious left ventricular cardiac configuration and hypertension. We need to look for various other aetiology like aortic coarctation, renal disease, masses with secretory capability or occasionally entity like APKD. If you carefully observe, you notice rib notching, subtle wavy outline of the inferior aspect of the ribs evident on the left side.  Reverse '3' sign is an another sign of coarctation, best appreciated in association with a barium esophagography. Upper half of the 3 is represented by dilated arch proximal to narrowing. Lower half of the 3 is due to post stenotic dilatation. Apart from coarctation there are many other causes of rib notching. This observation is generally seen in long-standing coarctation; early coarctation as detected in the present day may not show rib notching. Other important causes of rib notching are cardiac surgery, thoracic surgery, vascular malformations of the intercostal arteries and occasionally subclavian stenosis. Additional non-vascular causes are neurofibromatosis and rheumatoid arthritis. BT shunt for TOF is an occasional cause of unilateral rib notching.

Case 27

65-year-old male patient with chest pain and dyspnoea.

Coronal and sagittal images of contrast-enhanced chest are provided.

Diagnosis should not be very difficult. Certainly there is aneurysmal dilation of arch and descending thoracic aorta. Lumen is somewhat reduced and shows irregular outline with a focal narrowing in the upper thoracic aorta due to a thrombus. Differentiating a chronic, thrombosed aortic dissection vs. aortic aneurysm with a thrombus can be an occasional challenge. If you notice carefully there is a peripheral wall calcification. So what we are seeing is likely to be a large circumferential thrombus in an aneurysm. In case of the dissection showing thrombosis, calcified elements may be next to the lumen. Did you notice an extension of the thrombus into the great arteries? Did notice any other observation in the sternum?

Case 28

This is a 3-month-old female with the suspected congenital heart disease, peculiar facial clinical features. Investigated for demonstrating cardiac morphology. Plain images of the chest and the additional images of the upper thoracic spine and the contrast-enhanced mediastinum is provided.  

I have provided you with lot more information in one go rather than testing your radiology skills. Reason is the multiplicity of observations in this patient. Initially in the chest radiography do you suspect any abnormality? If you think the mediastinum is somewhat wide, you're right. Indeed there is widening of the mediastinum with a straight left border. Additional abnormalities in the form of a subtle increase in the hilar arterial pattern is also present. Cardiac size is the upper limit of normal. Rest of the chest appears normal. What is seen on image (b) ? This is a coronal contrast enhanced image. You should be able to appreciate a somewhat large superior vena cava on the right side; there is a vertical vessel(vein) on the left side of mediastinum, adjacent to the pulmonary artery. We will explore this further in the next image. Meanwhile you will see a segmentation anomaly of the spine involving upper thoracic vertebra in the form of hemivertebra, hypoplastic disc and rib anomalies.

In the following part, I have provided many images including curved reconstructions. Indeed the left vertical vein is seen (arrow) constituted by left inferior pulmonary veins (open arrow). After originating from the inferior pulmonary veins on the left side, the vertical vein ascends up, joins the innominate vein and further to the enlarged superior vena cava. This is an instance of a partial anomalous pulmonary venous drainage of lower lobe. 

Case 29

8-year-old child with exertional dyspnoea and cyanosis. Pre-and post-operative chest radiographs are provided.

Abnormality is striking in the form of a grossly dilated cardiac shadow. Heart is enlarged on both sides. Lungs however appear somewhat oligaemic, certainly not plethoric. If you want to explore further regarding specific chamber enlargement, this case is challenging. If you think cardiac chambers are enlarged, certainly the right atrium and left ventricle must be large in this case. However not all cases of a large heart will be due to enlarged chambers. Gross cardiac enlargement is seen in patients with dilated cardiomyopathy, multiple valvular disease, Ebstein’s anomaly, pericardial disease with gross fluid collection and occasionally other causes of pseudo-cardiac enlargement. This patient had Ebstein’s anomaly of tricuspid valve was operated subsequently

Case 30

5 year old child with dyspnoea on exertion, cyanosis, short stature.

Chest radiograph and contrast-enhanced reconstructed images of cardiac chambers are provided. Interpretation of this chest does not offer too many observations. Initially the impression is, lung vasculature may be on the lower limit of normal. Cardiac size is not enlarged, configuration? Biventricular. Aorta appear somewhat large for their age. Along with the clinical input the diagnosis of tetralogy of Fallot can be made. Cardiac CT angiography however is much more informative. In image (b)  you will see that aorta is much larger compared to the pulmonary artery, which is reduced in caliber and shows valvular stenosis. This information is better appreciated in a coronal view (d) which also shows that there is narrowing of the infundibulum along with valvular stenosis. The branches pulmonary arteries are also somewhat smaller, right more smaller than the left. Lastly we will see in an oblique reconstruction, a large subaortic ventricular septal defect and overriding aorta. This is a classical case of Tetralogy of Fallot. More details will be provided in the form of additional cases elsewhere else in this web content

Case 31

A 2-month-old child investigated for suspected cardiac disease on echocardiogram.

Plain chest radiographs and reconstructed images of the CT angiogram are provided.

This is one of the instances wherein some useful impression can be obtained from plain radiography. As mentioned earlier in the series, a plain radiograph helps us to look at the lungs in order to study perfusion. This patient has increased pulmonary arterial markings, an indication of the high lung pulmonary arterial volume. This is an indication of a shunt circulation. If you look at the images further you will notice that the aortic knuckle is somewhat prominent and there is a mild enlargement of the left atrium. Cardiac size also has marginally increased. CT angiography shows dilatation of the pulmonary arteries and the branches. This conclusion we can make by comparing the size of the pulmonary artery with the adjacent ascending aorta. Normally they are nearly similar. But interestingly there is a tortuous vessel that appeared to connect aorta with pulmonary artery. This is a very tortuous ductus arteriosus. So we are dealing with a case of ductus arteriosus with a large left-to-right shunt. In many instances ductus may be present as part of the complex cardiac anomaly. In this instance it was an isolated disease.

Case 32

Plain radiograph, barium study of esophagus, CT images and MRA images of the early 90s is provided. This is just to revisit the practice of the past. Plain radiograph is unremarkable in a patient who had feeding problem. Esophagus reveals performed, to exclude reflux–structural disease. Again noted is a linear impression in the upper esophagus obliquely oriented towards right shoulder. This is a signature of the aberrant right subclavian artery on an esophagram. CT images in the arterial phase demonstrate aberrant right subclavian artery. Same observations are confirmed on the MR angiography.

Case 33

With this case I am providing more exercise case for the residents. This patient had a cardiac procedure. Chest radiograph interpretation is an intended exercise. What is your impression? 

I hope that you have noticed with double density on the right side extending beyond the cardiac contour. There is a biventricular/left ventricular cardiomegaly. Any gas regarding the diagnosis? By the way, do you notice the right aortic arch?

CT images demonstrate dilated ascending arch and descending aorta in a right aortic arch. There is left ventricular enlargement. This patient had repair of an aortic coarctation. This is a postoperative follow-up examination. This procedure was performed in those days when balloon angioplasty did not exist .

Case 39

There are sets of images consisting of a chest radiograph and non-contrast CT images and reconstructions. The impression on the chest is that of a lobulated mass in the mediastinum, bulging on both sides. I guess you have noticed the compression of the left bronchus and contralateral displacement of the distal trachea. Many differential diagnoses are possible, in this context probably aortic aneurysm is very likely. Subsequent CT images confirm our impression. 

The reason why I present this case non-Contrast CT is to familiarize you with the plain CT appearance of an aortic aneurysm. Atherosclerotic aneurysms in the old patients, like in our patient, are characteristic. Wall calcification is often seen which are characteristically missing or deficient in the aneurysmal areas due to expansion. Distribution of calcification helps to separate ecstatic aorta against the aorta with an aneurysm. Another point to note is to localize the calcification in relation to the aortic lumen. Displacement of the calcium plaque towards the center of lumen suggests a possible aortic dissection. Also note should be made about the extent of calcification in the coronaries which is a comorbidity factor.

Case 40

This is a lady who presented with lower limb pain and referred for exclusion of possible vascular etiology 

I had presented this case earlier in the Ultrasound section. In the context of sonography this entity is extremely tricky to make a correct diagnosis. Presnetly CT angiography is a practical, conclusive modality for optimal patient management for lower extremity vascular lesions. We will concentrate our attention to distal aorta, aortic bifurcation, and its branches; common iliac, external iliac and femoral arteries. In our patient we do normal vascular divisions, although the size of external and femoral arteries appears somewhat smaller on both sides. This observation should ring the bell. Looking carefully at aortic continuation, there is additional continuation of the aorta through the sciatic notches into sciatic arteries. Distally sciatic arteries anastomosis in the distal third of the thigh, reconstituting flow to the leg. Several complications are associated with this anomalous course of the lower limb arteries. You might have noticed an aneurysm on the right side and the ectatic vessel on the left. Common complications are vascular occlusion, aneurysm formation, vascular ectasia, and rupture. 3-D rendered images provide a good idea about the anatomy, morphology, and pathway of these abnormal vessels.

Case 41

Frontal view of the chest and few MR images of the heart are provided in a patient who presented with exertional dyspnoea and pain.

Chest imaging findings are straightforward. There is mild cardiomegaly with enlargement of the left atrium. Right atrium also appears somewhat prominent. All the findings point towards a mitral valve disease. Some observations of importance in this patient are the absence of calcification in the mitral valve and absence of severe signs of pulmonary venous congestion. (Mild upper lobe vessel prominence is present). For morphological assessment several standard views are obtained in MR imaging. You have a 4-chamber view axial, (lower left) 3 and the 2 chamber views - displaying mitral valve and mitral aortic relations. What is your conclusion on these images? Is it mitral stenosis/mitral regurgitation/both?  This patient has a predominant regurgitation element, thus left ventricle as well as left atria are grossly enlarged. Also, we do not see gross valve thickening or formation of a dome at the mitral level, excluding significant stenosis. Quantitative information flow and regurgitant phenomena can be demonstrated in phase contrast imaging at the flow regions of the valve

Case 44

This case presents an interesting imaging scenario. 5-year-old patient presented with acute onset chest pain. Initial plain radiographic investigations and the subsequent CT imaging are provided. The initial radiograph demonstrates a classic right-sided tension pneumothorax. I am sure you have seen signs of mass-effects in the form of cardio-mediastinal shift, contralateral tracheal shift, and flat, depressed right diaphragmatic dome. Did you notice the right aortic arch? After chest tube drainage, there is expansion of the right lung and resolution of pneumothorax. Subsequently the patient was investigated with a barium swallow, which demonstrated a posterior esophageal extrinsic impression with an oblique course on the frontal view.  Bandlike extrinsic impressions on the posterior wall of the oesophagus are almost always due to vascular impression. 

Contrast enhanced CT evaluation shows some additional observations. Right aortic arch is confirmed. Additionally, you notice an aberrant left subclavian artery, traversing behind the airways and oesophagus to reach its destination.  Also there appears to be a left sided tracheal compression by the left common carotid artery constituting an incomplete vascular ring. Findings are substantiated in the 3D views. Patient had a complex congenital heart disease with atrial and ventricular septal defects. This case presents an unusual initial manifestation in a patient with a complex cardiovascular anomaly. Please note somewhat crude 3D reconstructions, due to limited options of the early CT units.

Case 45

MR angiogram and T1-weighted images are provided in a patient with a suspected congenital heart disease. What are your observations?  I am sure you have observed the right aortic arch, although some confusion may be present about the rounded vascular structure on the left side of the upper descending aorta. In this patient descending aorta pursues a left sided course. Visceral situs is normal. In the provided MRA branching pattern of the right aortic arch is visualised. The first 3 branches are seen to arise normally. The left subclavian, apparently arises from a pouch like aortic diverticulum. This entity is known as Kommerell diverticulum. This condition may be associated with the cardiac disease or occasionally seen in isolation. Symptoms vary with the size of diverticulum. Signs of esophageal compression may be a presenting feature. Complications can occur in the form of thrombosis or occasional rupture of the diverticulum

Case 46

This is an additional patient, younger hypertensive evaluated with plain radiography, Doppler examination of the kidneys and an MR angiography.

Initially the plain radiography demonstrates scoliosis of the lumbar spine with gross rotation and curvature to the right side. No additional information is available on plain film. There are many observations in the US and Doppler examination. Significant change in the caliber of abdominal aorta in the upper and the lower part. Some transition to reduction in caliber normally occurs after the origins of the renal and mesenteric arteries. In this case this discrepancy appears very evident. Secondly, the right kidney demonstrates dilated renal pelvis. Both renal sizes appear normal. In the Doppler examination, technically optimal examination was possible on the right side, which loe PSV and spectral broadening. Doppler parameters are as follows: PSV 40cm/sec, ED 14 cm/sec, TA Max 25.4cm/sec, PI 1.2, RI 0.65. Limited information is available on the left side, with the low PSV and spectral broadening, PSV 35cm/sec and ED 20 cm/sec. Doppler observations were not classical.  In our case, significant narrowing of the aorta with reduced flow to the kidneys can result in values observed in our patient. Patient underwent MR angiography. You notice that there is a reduction in the caliber of the aorta, just below the origin of SMA, extending down for a few centimeters. In the early phase of the examination relatively small caliber main renal arteries are shown. There is a good renal parenchymal phase. A large defect is noted in the lower pole of the right kidney, probably a renal infarct with scarring. In essence we are dealing with the aortic disease with reduction in the caliber, possible involvement of the origins of the renal arteries. Differential diagnosis as mentioned in the earlier illustration, namely Aorto-arthritis, Takayasu disease and neurofibromatosis.

Renal artery stenosis is a broad topic.

Renal artery stenosis and relatively in the patient’s may be caused by several pathological processes:

• fibromuscular dysplasia (~20%) involves the distal renal artery, younger population

• vasculitides (especially polyarteritis nodosa-causing multiple microaneurysms, Takayasu arteritis, radiation)

• neurofibromatosis type 1- most commonly involves the ostium

• abdominal aortic coarctation

• segmental arterial mediolysis

• Williams syndrome

• atherosclerosis (~75% of cases) involves the proximal renal artery

• aortic dissection

Sonographic findings and classical studies can lead to the correct diagnosis. Technical precision and consistency is very important. Sonographic observation of importance in a typical case are

(Radiologic Assessment of Native Renal Vasculature: A Multimodality Review. Sayf Al-Katib, Monisha Shetty, Syed Mohammad A. Jafri, and Syed Zafar H. Jafri RadioGraphics 2017 37:1, 136-156)

Radiologic Assessment of Native Renal Vasculature: A Multimodality Review. Sayf Al-Katib, Monisha Shetty, Syed Mohammad A. Jafri, and Syed Zafar H. Jafri RadioGraphics 2017 37:1, 136-156)

Case 47

MRA examination of the 12-year-old female patient with hypertension is presented. This patient shows narrowing of the aorta at the level of the renal arteries. Both renal arteries appear to be involved with reduction in caliber. Left renal arteries being stented. There is some indirect suggestion of collateral vessels in the bowel indicating possible narrowing of the origin of the mesenteric artery. Vascular diseases are uncommon in pediatric age groups. Occasional cases  Aorto-arteritis, Takayasu disease and the neurofibromatosis related syndromes can be considered as an etiological factor.

Case 50

Young child with suspected cardiac disease is evaluated with plain x-ray and CT images. This example is just to familiarize you with the CT images in the early 2000. Plain films show mild enlargement of the heart and prominent hilar shadows. Otherwise, lungs appear unremarkable. No specific diagnosis is possible on the plain x-ray. CT angiography shows presence of a post ductal aortic coarctation with patent ductus - although images are not great, the diagnosis is obvious. Also note a very crude 3D rendering. The major improvement in the current technology is a faster speed of acquisition, thus optimizing bolus timing and obtaining images in sub-seconds. Major improvement is achieved by improving tube design, increasing detector deficiency and faster image processing techniques.

Case 50

MR examination of the 2-year-old child with breathing difficulty and a cardiac murmur is presented. This illustration is yet another example of a cardiac MR examination performed in 2000. You see that there is a more frequent use of T1 sequences due to short acquisition times. Emphasis of imaging was more morphological. MR angiography had a complementary role, showing the sequence of opacification and the gross morphology of the vessels and cardiac chambers.

This patient does not pose a great diagnostic challenge as evident dilatation of the main pulmonary artery and proximal pulmonary arteries are demonstrated unequivocally. There is no narrowing at the pulmonary artery either at the level of the valve or at the right ventricular outflow tract. There is enlargement of the right ventricle and right atrium. Dynamic contrast MR angiography demonstrates normal sequence of vascular and chamber opacification. A hugely enlarged pulmonary artery is redemonstrated. Patient underwent cardiac catheterization and the diagnosis of the absent pulmonary valve with the gross pulmonary regurgitation was confirmed. Pulmonary arteries demonstrated aneurysmal dilation; a common finding associated with absent valves .

Presently Cardiac MR( CMR) is the gold standard of cardiac imaging. What changes lead to this unique change? Following developments in the present state of the art MRI units made the difference. 

Improvements in MRI hardware(magnet strength, coil design), data acquisition techniques( sequences,gating, K space management) and the enhanced reconstruction capability has made cardiac MRI (CMR) gold standard for cardiac evaluation. CMR has immense capability in evaluation of

1. Myocardial function, quantifying myocardial volumes, and detecting myocardial scar.

2. CMR also has the unique ability to provide detailed tissue characterization, including assessment of edema, iron overload, and diffuse myocardial fibrosis.

3. CMR is recommended for evaluation of congenital heart disease, heart failure, and coronary artery disease (CAD).

Major technical factors that led to improvement in cardiac imaging are:

1. Shift from the sequential cartesian grid data acquisition to parallel imaging and k-t-Accelerated Imaging. Parallel imaging improves the data acquisition by 2-3-fold. Parallel imaging techniques are known by acronyms such as Sensitivity Encoding (SENSE), Generalized Auto-calibrating Partial Parallel Acquisition (GRAPPA), and Auto-calibrating Reconstruction for Cartesian imaging (ARC),Images can be reconstructed with a reduced number of data lines using techniques such as k-t Broad-use Linear Acquisition Speed-up Technique (BLAST),  k-t SENSE, or k-t Principal Component Analysis (PCA). These innovative techniques have enabled 3D perfusion imaging, 4-dimensional flow, and real-time imaging with high temporal and spatial resolution. Accelerations of 12× have been achieved using these techniques for 3D data acquisition. Major limitation of these techniques is data corruption by respiratory motion.

2. Compression sensing (CS) is another technique which allows image reconstructions with fewer data lines. CS has been used for perfusion imaging, flow imaging, angiography, T1 mapping, and real-time free-breathing cine imaging. The CS technique has also been applied to continuously acquired free-breathing radial techniques, such as in the Extra-Dimensional Golden-angle Radial Sparse Parallel Imaging (XD-GRASP) technique, which enables separation of the data in both cardiac and respiratory dimensions without the need for cardiac gating or breath holding

3. With hardware and software improvements, first-pass perfusion imaging using CMR has emerged as a valid alternative to single photon emission computed tomography myocardial perfusion imaging (MPI). Current MRI techniques typically image 3 short-axis myocardial slices (thickness, 8–10 mm) with an in-plane resolution of 2 to 3 mm for conventional methods and <2 mm for advanced high-resolution.

4. Other notable improvements are Whole-Heart Spatial Coverage, Improved Imaging of Subendocardial Perfusion, Quantitative Perfusion CMR in CAD and Microvascular Dysfunction,

5. Non-contrast Parametric Mapping Techniques (T1, T2, and T2*) and Non-Breath-Hold and Non-ECG-Gated CMR Techniques. 

6. Additional dimensions like diffusion parameters (DTI) of cardiac tissues, 4D flow imaging etc. are being actively evaluated

(Recent Advances in Cardiovascular Magnetic Resonance Techniques and Applications Michael Salerno, Behzad Sharif. Håkan Arheden et al. https://doi.org/10.1161/CIRCIMAGING.116.003951Circulation: Cardiovascular Imaging. 2017;10: e003951)

Case 51

This young child had an unusually sharp pointed facial features and the laxity of joints. There were some abnormalities on the echocardiography which led to the investigations

We have an early radiograph taken in the neonatal period, in the third month. This may be a difficult radiograph for interpretation. I noticed that the aorta is somewhat prominent for the age. Also, there is an incidental right diaphragmatic hump. Findings may not be very specific, but could indicate some findings of arterial tortuosity syndrome. Subsequently the patient presented after 6 months. Now the radiographic observations are evident. There is cardiomegaly and evident aortic dilatation. On catheter angiography the patient showed evidence of a peripheral pulmonary stenosis involving the right pulmonary artery. Also noted is unusual tortuosity of the pulmonary arteries and the ‘V’ sign pulmonary artery. (Deep notch of pulmonary bifurcation) Patient underwent an open surgery and vessel reconstruction. However further radiographs do indicate increased dilatation of the main pulmonary artery suggesting disease progression. Patients with arterial tortuosity are difficult to manage. Surgical procedure likely to accentuate the disease progression, formation of aneurysm and subsequent rupture.

Case 53

MR examination of a 9-year-old child with exertional dyspnoea is provided. This case revisits MR images of the early 2000. We have been provided conventional images, MR angiography and phase contrast imaging. If you evaluate the axial images you will notice significant discrepancy in the size of the ascending and descending aorta. This can be an important clue to the possibility of aortic coarctation. [ Q:What do you think about the linear lines which are seen in the mid part of the image? Understanding artefacts is vital in MR imaging. I will leave it to you to explain this simple artefact]. In the postcontrast dynamic imaging we will see post ductal short segment coarctation. Findings are also collaborated in the phase contrast imaging. [Q:.: Why is this image appearing grainy -- explain the observation in terms of image analysis]. Other contrast-enhanced images also demonstrate a somewhat small calibre descending aorta and the normal appearance of pulmonary arteries. There is one additional image provided. Perhaps you know the anatomy and why this examination is performed. But the quality of the images is not good enough to exclude suspected abnormality. [Q.: Explain the beaded appearance of the blood vessels seen in this examination. Revisit the MR image acquisition technology and possible artefacts]