Pruitt, Raymond D.

The electrocardiographic findings were analyzed in 15 patients found at the time of necropsy to have deposits of amyloid in the heart. Although 12 of the 15 tracings were regarded as abnormal, changes which could be held to be specific to cardiac amyloidosis have not been defined. The most common alterations encountered were auricular fibrillation, QRS complexes and T waves of low amplitude in the standard limb leads, and impaired auriculoventricular conduction.

This reappraisal of the electrocardiographic manifestations of infarction of the lateral wall of the left ventricle is based on data acquired by simple and conventional technics. Categories of cases have been determined by the age of the infarct and the distribution of the lesion with respect to the circumference of the left ventricular wall and its epicardial and endocardial boundaries. Significant data have been presented in the form of illustrative diagrams and reproductions. The results do not establish a simple pattern common to all cases of infarction of the lateral wall; they do illustrate the varied yet limited electrocardiographic consequences of such lesions.

Administration of a moderately large or large dose of cortisone to dogs having acute myocardial infarctions inhibited slightly the rate of removal of necrotic muscle fibers in these animals as compared with untreated animals. Delay was appreciable at four and six days after production of the infarct in animals receiving 2.5 mg. of cortisone per kilogram of body weight and at 4, 6, 12 and 21 days in animals receiving 10 mg. per kilogram. At all other periods up to essentially complete healing of the infarcts as defined at 60 days, no appreciable differences existed between treated and untreated animals.

A correlation of the clinical and electrocardiographic findings was undertaken in 110 cases which had in common the presence of deeply inverted T waves in central terminal leads centered about position 3 on the precordium. The results of this study are reviewed. A summary is presented of changes encountered at the time of necropsy in nine cases in which electrocardiographic changes of similar type had been recorded. These observations are integrated with concepts derived from the dipole theory. The total evidence is viewed in relation to observations reported by other investigators.