RADIOLOGICAL EXAMINATION OF THE CARDIOVASCULAR SYSTEM

1. RADIOLOGICAL EXAMINATION OF THE CARDIOVASCULAR SYSTEM DEPARTMENT OF ONCOLOGY AND RADIOLOGY PREPARED BY I.M.LESKIV

2. METODS OF EXAMINATION • Echocardiography, radionuclide examinations and plain films are the standard non-invasive imaging investigations used in cardiac disease. Echocardiography has now become a particularly important imaging technique that provides morphological as well as functional information. It is excellent for looking at the heart valves, assessing chamber morphology and volume, determining the thickness of the ventricular wall and diagnosing intraluminal masses. Doppler ultrasound is an extremely useful tool for determining the velocity and direction of blood flow through the heart valves and within cardiac chambers. Radionuclide examinations reflect physiological parameters such as myocardial blood flow and ventricular contractility but provide little anatomical detail, whereas plain radiographs are useful for looking at the effects of cardiac disease on the lungs and pleural cavities, but provide only limited information about the heart itself. MRI provides both functional and anatomical information but is only available in specialized centres and is used only for specific reasons.

3. ROENTGENOGRAPHY • A complete roentgen study of the heart usually requires a minimum of four projections: posteroanterior, left anterior oblique at approximately 60°, right anterior oblique at approximately 45°, and lateral. The films are exposed at a 6-foot distance, with the patient in the upright position and in moderately deep inspiration. Magnification resulting from divergent distortion is minimized by obtaining posteroanterior and anterior oblique views to place the heart closer to the film (the anterior chest is adjacent to film). A left lateral view (with the left side adjacent to film) also tends to minimize magnification. To outline the esophagus, we use a barium suspension as an aid in determining position and size of the aortic arch. In addition, alteration inesophageal contour may reflect changes in the left-sided chambers. The use of ultrasound in determining cardiac chamber size has decreased the use of the oblique projections, so that frequently the cardiac examination is restricted to PA and lateral projections, usually without barium in the esophagus.

4. Plain Radiography : * The standard plain films for evaluation of cardiac diseases are the PA view & Lateral chest film, the PA view must be sufficiently penetrated to see the shadow within the heart, eg. The double contour of the Lt. atrium & valve & pericardial calcification. * It provides limited information's about the Heart. * It provides limited information's about the effect of the cardiac diseases on the lungs & pleural cavities. We should assess the following points : • a- Heart (shape & size). • b- Great vessels (size, shape), Aortic arch (normally located to the Lt. of the Trachea, we should exclude the signs of coarctation of aorta). • c- If there is any calcification. • d- The main point is the examination of the Lung field for altered blood flow & if there is any evidence of heart failure.

5. Normal CXR in PA view

6. Normal CXR in Lateral view

7. FLUOROSCOPY • Cardiovascular fluoroscopy no longer has widespread use and in our institution is largely limited to the evaluation of specific questions: i.e., the presence of large pericardial effusions and the evaluation of aortic arch anomalies. Generally, calcium is better seen on fluoroscopy then on plain films and these observations may be made at the time of cardiac catheterization. Minor amounts of calcification are best seen on CT. The use of fluoroscopy has virtually disappeared in the study of congenital heart disease because in general the patients require more definitive studies such as cardiac catheterization, angiocardiography, ultrasonography, and MRI. • There are several disadvantages in cardiac fluoroscopy, one of the most important of which is the amount of radiation to which the patient is exposed. • The second disadvantage is distortion. Because the distance between the target of the x-ray tube and the patient is short, there is considerable enlargement of the cardiac silhouette and distortion of other thoracic structures. This can be decreased by using longer distances between target and the patient, and by using a small shutter opening, producing the central beam effect. The third disadvantage is lack of permanent record. This is obviated to a certain extent by the use of cine or videotape recording and by roentgenograms obtained before the procedure.

8. ANGIOCARDIOGRAPHY • This method of contrast cardiac visualization has been used widely for examination of patients with all types of cardiac and pulmonary diseases. The method is used in the diagnosis of congenital and acquired cardiac disease. Selective angiocardiography in which a small amount of opaque medium (an organic iodide) is injected into a specific chamber or vessel during cardiac catheterization is used almost exclusively.

9. CORONARY ARTERIOGRAPHYAORTOGRAPHY • CORONARY ARTERIOGRAPHY • Selective catheterization of the coronary arteries followed by injection of a contrast medium (one of the organic iodides) is used in combination with cineradiography rapid serial filming or videotaping to study the coronary arteries. Details of technique are beyond the scope of this discussion. • AORTOGRAPHY • This examination consists of the injection of one of the organic iodides into the aorta through a catheter introduced into one of its major branches and placed into a desired position in the aorta. The examination has a place in the investigation of patients with congenital and acquired problems of the aortic arch. It is used in infants with congestive heart failure in whom there is evidence of a left to right shunt and in whom patent ductus arteriosus is suspected. Coarctation of the aorta in infants may also cause congestive heart failure. The lesion can be defined by aortography. In adults, aortography is used to define anomalies of the aortic arch and its branches as well as in the study of the aortic valve and the coronary arteries. It is also useful in patients with masses adjacent to the aorta in whom aneurysm is a possibility and in patients suspected of having dissecting hematoma, and traumatic or other aneurysms.

10. ULTRASONIC INVESTIGATION OF THE HEART • The use of ultrasound in examination of the heart has increased greatly in the past 20 years, and it is now well established and a widely used diagnostic tool. Ultrasonic investigation is a noninvasive, safe, and comfortable study that will demonstrate valve and chamber motion wall thickness and size. Doppler examination allows determination of the cross sectional area of a valve as well as quantification of gradients that may be present. It is of value in the study of the hypertrophic cardiomyopathies both with and without associated subaortic stenosis and in the study of the congestive type in which there is chamber dilatation. With ultrasound, left ventricular diameter and outflow configuration can be determined; qualitative assessment of right and left ventricular size is possible, also. The size of the left atrium can be measured accurately and left atrial myxomas or other intraatrial tumors can be detected. Ultrasound is also useful in the investigation of congenital heart disease, particularly in patients with hypoplastic left-heart syndrome, double-outlet right ventricle, and right ventricular volume overload. In addition, it is the most sensitive method for determining the presence of pericardial effusion.

11. Echocardiography(Cardiac US) * It is the major or basic imaging technique used in cardiology. * It gives important informations about the Morphology & Function of the heart. * It is an excellent technique to look for : a- Heart valves. b- Chamber morphology & volume. c- Determining the ventricular wall thickness. d- Any intra-luminal mass. 3 basic techniques are used in Echocardiography, & they are : • M-mode : • Two-dimensional sector scanning (Real time echo.) • Doppler echocardiography (Color, Pulse wave)

12. Echocardiography M-mode • * It is a continuous scan over a period of time (5-10 seconds), with pencil – beam of sound directed to thesite of interest. • * It can demonstrate chamber dimensions, wall thickness, & valve movement (mainly for Lt. ventriculardimension in systole & diastole).

13. M-mode

14. Two-dimensional sector scanning (Real time echo.) : * Demonstrates fun-shaped slices of the heart in motion. * Standard examination consists of combination of short & long axis views + 4 chamber view. * Long & short – axis views : cross-section of the of the Lt. ventricle + mitral valve + aortic valve, & it isdone by placing the transducer in the intercostal space, just to the Lt. of the sternum. * 4 chamber view : both ventricles, both atria, mitral & tricuspid valves, & it is done by placing thetransducer at the cardiac apex & aiming upward & medially.

15. 4 chamber view in 2 dimensional scan

16. Para-sternal long axis

17. Para-sternal short axis

18. Apical 4 chamber view

19. Para-sternal short axis (at Mitral valve level)

20. Doppler echocardiography (Color, Pulse wave) : * Changing in the frequency of the sound waves are reflected from moving objects, this change dependson the velocity of the reflecting surface. * RBCs are used as reflecting surface & the velocity of the blood flow can be measured.

21. Doppler flow measurements are used to : 1- Measure cardiac output or Lt. to Rt. shunt. 2- Detect & quantify valvular regurgitation. 3- Quantify pressure gradients across stenotic valves. 4- Quantify flow.

22. Trans-Esophageal Echocardiography : * By placing the U.S. probe in the esophagus immediately behind the Lt. atrium, so it will view the heartfrom behind. (A = normal descending thoracic aorta)

23. DETERMINATION OF CARDIAC SIZE • The most commonly used are (1) measurement of transverse diameters; (2) measurement of surface area; and (3) cardio-thoracic ratio. The transverse diameter of the heart is the sum of the maximum projections of the heart to the right and to the left of the midline; the measurement should be made so as not to include epicardial fat or other noncardiac structures. The diameter can then be compared with the theoretic transverse diameter of the heart for various and weights. Surface area estimations based on artificial construction of the base of the heart and of the diaphragmatic contour of the heart. The cardiothoracic ratio is the ratio between the transverse cardiac diameter and the greatest internal diameter of the thorax, measured on the frontal teleroentgenogram. This is the easiest and quickest method of measurement of cardiac size; an adult heart that measures more than one half of the internal diameter of the chest is considered enlarged. The method is gross, because the cardiothoracic ratio varies widely with variations in body habitus. It can be useful, however, as a rough estimate of cardiac size. The cardiothoracic ratio is most useful in assessing changes in heart size or monitoring progression of disease, or as a response to therapy.

24. Heart Diseases * Evidence of heart diseases is given by : 1- Size & shape of the heart. 2- Pulmonary vessels, which provide information about the blood flow. 3- The lungs, which may show pulmonary edema.

25. Measurement of heart size. The transverse diameter of the heart is the distance between the two vertical tangents to the heart outline. When the cardiothoracic ratio (CTR) is calculated, the transverse diameter of the heart (B) is divided by the maximum internal diameter of the chest (A)

26. Heart size : * Cardio - Thoracic Ratio (CTR), is the maximum thoracic diameter of the heart divided by the maximum thoracic diameter, in adult CTR > 50% while in children CTR > 60%.

27. Heart size : * Comparing with previous films chest-x-ray films is often more useful. - The transverse cardiac diameter varies with the phase of respiration & with cardiac cycle, so if thechange in the cardiac size is < 1.5 cm; this is negligible because the heart size is affected by breathing & cardiac cycle. * Overall increase in the heart size means : - Dilatation of more than one cardiac chamber. - Pericardial effusion.

28. Chamber hypertrophy and dilatation : • * Pressure overload (as in : Hypertension, Aortic Stenosis, Pulmonary Stenosis), this will lead to • ventricular wall hypertrophy, & such change will produce little change in the external contour ofthe heart, until the ventricle fails. • *Volume overload (as in : Mitral Incompetence, Aortic Incompetence, Pulmonary Incompetence, Lt.to Rt. Shunt, & Damage of the heart muscle), this will lead to dilatation of the relevant ventricle, &this will cause an overall increase in the size of the heart (increase in the transverse cardiac diameter). • * Because enlargement of one ventricle affects the shape of the other, so it is only occasionally possible to get the classical feature Lt. or Rt. Ventricular enlargement.

29. Lt. Ventricular enlargement - Lt. Ventricular enlargement, the cardiac apex is displaced downwards and to the left. Note also that the ascending aorta causes a bulge of the right mediastinal border - a feature that is almost always seen in significant aortic valve disease. Lt. Ventricular enlargement in a patient with Aortic Incompetence

30. Rt. Ventricular enlargement - Rt. Ventricular enlargement, the cardiac apex is displaced upward (to the Lt. of diaphragm). Note also the features of pulmonary arterial hypertension - enlargement of the main pulmonary artery and hilar arteries with normal vessels within the lungs. Rt. Ventricular enlargement in a patient with Primary Pulmonary Hypertension

31. Lt. Atrial Enlargement : * When it produces Double Contour, the Rt. border of the enlarged Lt. atrium is seen adjacent to the Rt. Cardiac border within the main cardiac shadow. Lt. Atrial Enlargement in a patient with Mitral Valve Disease showing the “Double Contour Sign” (the left atrial border has been drawn in) and dilatation of the left atrial appendage (LAA) (arrow). Lt. Atrial Appendage : The enlarged LAA should not be confused with dilatation of the main pulmonary artery. The main pulmonary artery is the segment immediately below the aortic knuckle. The LAA is separated from the aortic knuckle by the main pulmonary artery

32. Rt. Atrial Enlargement * Will produce an increase of the Rt. cardiac border, & often accompanied by enlargement of Superior Vena Cava (SVC).

33. Valve movement deformity & calcification Plain X-ray films : * Calcification is the only could be obtained directly related to the morphology of the valve. * Calcification is better seen by fluoroscopy. * It occurs in mitral valve &/or aortic valve in rheumatic heart diseases; & if it occurs in aortic valvealone (especially in adults) it is mainly congenital aortic stenosis. * It is the easiest & the best to see calcification by the lateral view by drawing a line from the junctionof the diaphragm & the sternum to the Lt. main bronchus, so : - If the calcification is below & behind, means mitral valve. - If the calcification is above & in front, means aortic valve. * If the line dissects the calcification, both valves (mitral & aortic) are calcified. * Calcification of the mitral valve ring + elderly patient is occasionally seen in mitral regurgitation.

34. Valve calcifications Mitral Valve Calcifications

35. Valve calcifications Aortic Valve Calcifications

36. Ventricular Contractility * General uniform decrease contractility in valvular disorder, congenital cardiomyopathy, &multi-vessel coronary artery diseases. * If there is focal decrease in contractility +/- dilatation in IHD. * Increase contractility of the Lt. ventricle will cause hypertrophy as in aortic stenosis, HTN, &hypertrophic obstructive cardiomyopathy (HOCM).

37. THE ADULT HEART

38. Pericardial disease • Echocardiography is ideally suited to detect pericardial fluid. Since patients are examined supine, fluid in the pericardial space tends to flow behind the left ventricle and is recognized as an echo-free space between the wall of the left ventricle and the pericardium. A smaller amount of fluid can usually be seen anterior to the right ventricle. Even quantities as small as 20-50 ml of pericardial fluid can be diagnosed by ultrasound. The nature of the fluid cannot usually be ascertained, and needle aspiration of the fluid may be necessary; such aspiration is best performed under ultrasound control. Pericardial effusion can also be recognized at CT and MRI, although they are rarely performed primarily for this purpose. Computed tomography and MRI are particularly useful for assessing thickening of the pericardium, whereas echocardiography is poor in this regard. • It is unusual to be able to diagnose a pericardial effusion from the plain chest radiograph. Indeed, a patient may have sufficient pericardial fluid to cause life-threatening tamponade, but only have mild cardiac enlargement with an otherwise normal contour. A marked increase or decrease in the transverse cardiac diameter within a week or two, particularly if no pulmonary oedema occurs, is virtually diagnostic of the condition. Pericardial effusion should also be considered when the heart is greatly enlarged and there are no features to suggest specific chamber enlargement. Pericardial calcification is seen in up to 50 % of patients with constrictive pericarditis. Calcific constrictive pericarditis is usually postinfective in aetiology, tuberculosis and Coxsackie infections being the common known causes. In many cases no infecting agent can be identified. The calcification occurs patchily in the pericardium, even though the pericardium is thickened and rigid all over the heart. It may be difficult or even impossible to see the calcification on the frontal view. On the lateral film, it is usually maximal along the anterior and inferior pericardial borders. Widespread pericardial calcification is an important sign, because it makes the diagnosis of constrictive pericarditis certain.

39. Pericardial Diseases • 20 – 50 ml of pericardial fluid is diagnosed by echo. • Needle aspiration is needed to insure the nature of the fluid. • CT scan & MRI can show the pericardial effusion; but more important is to measure the thickness ofthe pericardium where thickness of the pericardium where echo. is poor. • * Unusual to diagnose pericardial effusion by plain-X-ray because the patient may have pericardialeffusion to cause a life-threatening tamponade; but only mild heart enlargement with otherwise normal contour. • Marked increase or decrease in the transverse diameter of the cardiac shadow within on or twoweeks + No pulmonary edema is virtually diagnostic of pericardial effusion. • Marked increase in the cardiac size + no specific chamber + normal pulmonary vasculature (flask shape) (& the outline of the heart become very sharp) is diagnostic of pericardial effusion. • Pericardial calcification is seen in 50% of patient within constrictive pericarditis, which is usually due to TB or Coxsackie's virus infection. • Best seen on lateral CXR, along the anterior & inferior surface, because it may possible on frontalCXR. • * Usually the calcification is an important sign for constrictive pericarditis.

40. Pericardial Effusion Pericardial Effusion due to Viral Pericarditis

41. Pericardial Effusion Congestive Cardiomyopathy, this appearance usually confused with Pericardial Effusion

42. Pericardial effusion. The heart is greatly enlarged. (Three weeks before, the heart had been normal in shape and size.) The outline is well defined and the shape globular. The lungs are normal. The cause in this case was a viral pericarditis. This appearance of the heart, though highly suggestive of, is not specific to pericardial effusion. (Compare with (b).) (b) Congestive cardiomyopathy causing generalized cardiac dilatation. This appearance can easily be confused radiologically with a pericardial effusion. A B Pericardial calcification in a patient with severe constrictive pericarditis. The distribution of the calcification is typical. It follows the contour of the heart and is maximal anteriorly and inferiorly. As always, it is more difficult to see the calcification on the PA film. (This patient also had pneumonia in the right lower lobe.)

43. Pericardial Effusion Large Pericardial Effusion on an apical 4-chamber view echocardiogram

44. Large pericardial effusion on an apical four-chamber view echocardiogram. (b). CT scan showing fluid density (arrows) in pericardium. LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle.

45. Pericardial Effusion CT-scan shows fluid density (arrows) in the Pericardium

46. Pericardial Calcifications Pericardial Calcification in a patient with Severe Constrictive Pericarditis

47. Pericardial Calcifications Pericardial Calcification in a patient with Severe Constrictive Pericarditis

48. Pulmonary vessels • The plain chest film provides a simple method of assessing the pulmonary vasculature. Even though it is not possible to measure the true diameter of the main pulmonary artery on plain film, there are degrees of bulging that permit one to say that it is indeed enlarged. Conversely, the pulmonary artery may be recognizably small. The assessment of the hilar vessels can be more objective since the diameter of the right lower lobe artery can be measured: the diameter at its midpoint is normally between 9 and 16 mm. The size of the vessels within the lungs reflects pulmonary blood flow.There are no generally accepted measurements of normality, so the diagnosis is based on experience with normal films. By observing the size of these various vessels it may be possible to diagnose one of the following haemodynamic patterns. • Increased pulmonary blood flow:Atrial septal defect, ventricular septal defect and patent ductus arteriosus are the common anomalies in which there is shunting of blood from the systemic to the pulmonary circuits (so-called left to right shunts), thereby increasing pulmonary blood flow. The severity of the shunt varies greatly. In patients with a haemodynamically significant left to right shunt (2:1 or more), all the vessels from the main pulmonary artery to the periphery of the lungs are large. This radiographic appearance is sometimes called pulmonary plethora. There is reasonably good correlation between the size of the vessels on the chest film and the degree of shunting.

49. Pulmonary Vessels * It is not possible to measure the diameter of the MPA from the plain film (usually subjective); but ifthere are variable degrees of bulging, means enlarged MPA. * Assessment of the hilar pulmonary arteries is more objective & the diameter of the Rt. lower lobeartery at its mid-point (normally 9 – 16 mm). * The size of pulmonary vessels with the lung reflects the pulmonary blood flow. * Increase pulmonary blood flow is seen in ASD, VSD, & PDA, & all of these will lead to Systemic to Pulmonary (Lt. to Rt. shunt) & these will to increase pulmonary blood flow.

50. Pulmonary Vessels * Hemodynamically significant Lt. to Rt. shunt is (2/1 ratio or more) & this will produce CXR findings; if less ratio there will be no CXR findings & all the pulmonary vessels will (from the MPA to theperiphery of the lung) will be enlarged, & this is called "Pulmonary Plethora". * There is good correlation between the size of the vessel on CXR & degree of the shunt. * Decrease pulmonary blood flow, all the vessels are small "Pulmonary Oligemia". * The commonest cause of decrease pulmonary blood flow is TOF & pulmonary stenosis. * Obstruction of the Rt. ventricle outflow + VSD will lead to Rt. to Lt. shunt. * Pulmonary stenosis will cause oligemia only is severe cases & babies or very young children.