Left heart catheterization; the clinical importance of findings

Left heart catheterization using the transbronchial route to obtain pressures in the left atrium and left ventricle was used successfully in 29 cases with no mortality or morbidity. It was found to be useful in differentiating between mitral stenosis and mitral insufficiency, as well as determining the amount of aortic stenosis present when there was involvement of the aortic valve. The technique was also helpful in determining which is the predominant lesion when there is a disease of the aortic and mitral valves. In two patients in a series of 29, data obtained by left heart catheterization forestalled operation on the basis of a mistaken diagnosis of mitral stenosis when actually no mitral valvular disease was present. In another eight patients, the predominant lesion was found to be mitral stenosis rather than mitral insufficiency as it was thought to be before catheterization. In two patients, who had only systolic murmurs, catheterization revealed mitral stenosis rather than mitral insufficiency. In four patients who were thought to have mixed valvular disease, left heart catheterization showed only aortic valvular disease.     

‘Crystal-like structures’ of boiled beef heart mitochondria

Electron micrographs of boiled beef heart mitochondria are presented. On heating the mitochondrial suspension for 7 min in a boiling water bath ‘crystal-like’ structures inside and inbetween the mitochondria became visible.     

Valvular heart disease; the role of cardiac catheterization in preoperative evaluation

Cardiac catheterization studies performed in research laboratories showed that advanced mitral stenosis is associated with a characteristic dynamic pattern which is reversible by mitral valvulotomy. In the process of the selection of patients for mitral valvulotomy, occasionally there are instances in which a decision cannot be reached on the basis of ordinary clinical methods of examination. In some such cases cardiac catheterization may be of decisive value by demonstrating, or by failing to demonstrate, the dynamic pattern of mitral stenosis. Cases in which this diagnostic procedure is most often helpful are those of mild mitral stenosis and those in which there are combined valvular defects.     

Hypertrophy of the heart; electrocardiographic distinction between physiologic and pathologic enlargement

Electrocardiograms of marathon runners were examined to study hypertrophy of the heart due to prolonged physical exertion and to differentiate this from hypertrophy due to various disease states, especially essential hypertension, aortic valvular disease and coarctation of the aorta. The electrocardiogram of the marathon runners was characterized by a slow cardiac rate, high voltage of the QRS complexes and T waves in the standard and/or precordial leads with normal R/T ratios. There was moderate enlargement of the heart as observed on teleoroentgenogram. These findings are characteristic of physiologic hypertrophy of the heart and should be suspected among patients having a history of athletics calling for endurance. Immediately after running, all waves showed an increased voltage and the heart size decreased. The concept of the secondary T wave in hypertension as a part of the left ventricular strain pattern was challenged by the observation that the increased voltage of the R waves in lead V5 and other leads seen in marathon runners and in certain patients with hypertension, aortic stenosis, aortic insufficiency and coarctation of the aorta were not necessarily associated with typical discordant S-T segments and T waves. There was a higher incidence of dyspnea, angina pectoris and cardiac enlargement among hypertensive patients with discordant T waves than among hypertensive patients without these changes. Thus it is felt that the discordant waves are primary and are not merely secondary to the increased area of the R waves. Primary T waves suggest myocardial disease, possibly anoxia of the subendocardium.