Cardiac Aneurysm

Abstract

(1) The evolution of our knowledge of cardiac aneurysm and its morbid anatomy is shortly reviewed. (2) Cardiac aneurysms are usually due to coronary occlusion with resultant infarction, and rarely to syphilis, infective endocarditis, congenital defects, or trauma. A detailed necropsy report is given of a case ascribed to rheumatic necrosis of the myocardium. (3) Cardiac aneurysms, like infarcts, involve the left ventricle almost exclusively, and may best be classified as anterior or posterior, according to the coronary branch occluded. The great majority involve the anterior wall of the left ventricle, usually at or near the apex. (4) The clinical and radiological features of 15 cases of cardiac aneurysm are described, and in five of them the diagnosis was confirmed by necropsy. The significant clinical features are a history of coronary thrombosis, enlargement of the heart to the left, a normal or low blood-pressure, distant heart sounds, and an electrocardiogram most often indicative of anterior infarction (T1 type). Expansile pulsation separate from the apex-beat, or an extensive area of præcordial pulsation, are rare but suggestive signs. (5) Diagnosis depends mainly upon radiological examination. Anterior aneurysms cause enlargement of the heart to the left, with deformity of its contour. This deformity, seen from the front, may take the form of (i) broadening of the apex or angulation of the left border, giving the heart a square or rectangular appearance; (ii) elongation of the heart to the left; (iii) a diffuse bulge or, more rarely, a localised hump on the left border. In the right oblique position, “ledging” of the anterior heart border is of great diagnostic value. Posterior aneurysms are best seen in the left oblique position, and may displace the œsophagus. Aneurysm of the inter-ventricular septum has been known to cause enlargment of the heart to the right. Calcification of the aneurysmal wall, when present, is an invaluable sign. Radioscopy is essential to determine the optimum position for demonstrating the aneurysm, to observe the character of the pulsation, and to detect localised adhesion. (6) The differential diagnosis has to be made from an enlarged right ventricular conus, aortic aneurysm, especially that involving a sinus of Valsalva, calcified pericardium, loculated pericardial exudate or cyst, the para-apical triangle of fat, and from intrathoracic neoplasm or cyst.