Diastolic compliance of the left ventricle in man.

Two coordinates of left ventricular end-diastolic pressure (P) and volume (V) were provided by the infusion of angiotensin in 22 patients. The slope (k) of the ln P-V relation, coupled with knowledge of the operating (end-diastolic) pressure allows determination of end-diastolic volume compliance (dV/VdP). Estimates of end-diastolic compliance from a single coordinate of pressure and volume compared well (r equals 0.90) with the two coordinate method, whereas for specific compliance (deltaV/V1 deltaP) appeared to be misleading in cases of idiopathic hypertrophic subaortic stenosis and congestive cardiomyopathy. Since volume compliance is determined in part by the operating pressure, compliance may be reduced in small, normal or enlarged ventricles. Left ventricular linear compliance was derived from volume compliance and was normalized for left ventricular wall thickness. The product of linear compliance and end-diastolic stress provides an index of myocardial strain, termed "muscle fiber stretch," which may be related to systolic performance and thus allow comparison of length-performance relations in ventricles with normal and abnormal compliance.

Case report. Triple origin of left coronary arteries from right coronary artery: unusual case of single coronary artery.

A rare case of coronary anomaly is presented: all of the coronary arteries orignated from a single ostium located in the right coronary cusp. No clinical evidence of coronary pathology was recognized until the age of 57 years when the patient was found to have coronary obstructive disease. The single coronary artery had a main branch corresponding to the usual dominant right coronary artery. Three other branches separated from this and vascularized the areas normally receiving the circumflex and ramus medianus, the left anterior descending, and a large septal branch.

Acute bacterial endocarditis following traumatic ventricular septal defect.

Traumatic ventricular septal defect occur rarely although penetrating wounds of the heart rate are fairly common. The urgency for the surgical correction of traumatic ventricular septal defects has been debated. In life-saving instances where left heart failure or cardiac tamponade occur, the decision is simple. A case report of early bacterial endocarditis complicating traumatic ventricular septal defect in the first 12 hours following injury has been presented. Avoidance of this complication by early surgical correction is advocated.

His bundle electrograms in patients with congestive cardiomyopathy.

His bundle electrograms were obtained at rest and during atrial pacing in 16 patients with congestive cardiomyopathy. Increments in heart rate during atrial pacing were associated with progressive increases in the A-H interval in all patients. Three patients had abnormal conduction (prolonged P-H) proximal to the His bundle; atrial pacing resulted in second degree A-V block (A-H block) in these three patients at paced rates below 130/min; these three patients were on digitalis at the time of the study. Two patients ahd left bundle branch block associated with a prolonged H-V interval suggesting a conduction disturbance in the contralateral bundle system either at or distal to the branching portion of the His bundle. Two patients had H-V prolongation in the presence of a normal QRS duration which suggests delay in the bundle of His. Two patients with normal H-V intervals had marked prolongation of the total intraventricular conduction time (H-S prolongation). The His bundle electrogram uncovered abnormalities in atrioventricular conduction not apparent on the standard electrocardiogram and has allowed expansion of our knowledge regarding the electrophysiologic features of congestive cardiomyopathy.

[Usefulness of 2-dimensional echocardiography in detecting intraventricular thrombi in patients with acute myocardial infarction]. / Utilidad de la ecocardiografía bidimensional en la detección de trombos intraventriculares en pacientes con infarto agudo del miocardio.

The purpose of this study is to determine the importance of two-dimensional echocardiography performed soon after admission to the coronary care unit to provide useful information concerning wall-motion abnormalities, and to detect and characterize left ventricular thrombi. A major goal is to identify a subgroup of patients with acute myocardial infarction who are at risk for systemic embolization; in this subgroup the benefits of anticoagulation treatment would theoretically outweigh the associated risks. We studied 7 consecutive male patients, age range from 32 to 60 years, with acute myocardial infarction. Five patients had antero-septal infarction, 1 anterolateral and another had anterior wall infarction. We performed two-dimensional echocardiography within the first week after admission. All patients had severe apical-wall-motion abnormalities (akinesis or dyskinesis) and left ventricular thrombi. All patients received anticoagulation therapy. Two-dimensional echocardiography, performed one month after the first study, showed that the thrombi had decreased in size in 6 patients and could not be visualized in 1 patient. The noninvasive nature of echocardiography allows serial evaluations of patients with known left ventricular thrombi and permits assessment of the effect of therapy.