Myocardial infarction immediately following cardiovascular stress testing.

A 45 year old man with recent onset of atypical chest pain, who sustained an acute myocardial infarction within 15 minutes after a negative treadmill exercise test, is described. The clinical course was complicated by persistence of chest pain despite afterload reduction and electrocardiographic evidence of inferoapical myocardial infarction. Coronary arteriography three and a half months later revealed minimal obstructive disease.

Left main coronary artery disease in a 19-year-old woman. Treatment by saphenous vein grafting.

Syncope, palpitations, ventricular tachycardia, and electrocardiographic changes of acute myocardial ischemia in a 19-year-old woman resulted from significant narrowing of the left main coronary artery and its ostium, producing high-grade obstruction to flow as documented by selective coronary arteriography. Because of these findings and markedly positive results of cardiovascular stress testing, surgical treatment by aortocoronary artery saphenous vein bypass grafting to the left anterior descending artery was carried out. Four years postoperatively, the patient was asymptomatic, and there are no abnormal findings on cardiovascular stress testing.

Determination of left-ventricular volume from first-pass kinetics of labeled red cells.

A mathematical model is presented for the dynamics of a bolus of technetium-99m-labeled red blood cells through the left ventricle. It is used to correct for attenuation the count rate observed over the left ventricle during a conventional gated blood-pool study. The left-ventricular volumes are calculated from the corrected count rates and expressed as a percentage of total blood volume, or in absolute terms if a blood sample is obtained. The procedure is applied to a number of patients with nonvalvular cardiac disease. Cardiac volumes determined by the method are found to correlate well (r = 0.98) with those determined by contrast left ventriculography. The method is simple, requires no special equipment, and can be applied with existing computer software.

The clinical spectrum of cardiac fibroma with diagnostic and surgical considerations: noninvasive imaging enhances management.

A cardiac fibroma was successfully resected from the interventricular septum of a 25-year-old woman. The clinical data were correlated with a review of the data on 144 other patients, thereby providing a clinical profile and management strategy for this type of tumor. Initial manifestations of a fibroma were determined to be congestive heart failure (21%), tachyarrhythmias (13%), and chest pain (3.5%). A majority of patients were asymptomatic (36%) with abnormal physical findings or an abnormal chest roentgenogram. Finding the tumor at autopsy incidentally or on sudden death (23%) indicated the lethal potential. A few (3.5%) of the reports on patients with cardiac fibroma were without clinical data. Noninvasive imaging by echocardiography, computed tomography, and nuclear magnetic resonance improved the diagnosis. Surgical treatment was successful in 53 of the 84 patients for whom it was attempted.

Radionuclide determination of cardiac outputs and indices.

A radionuclide procedure for the determination of cardiac output is presented. Cardiac outputs estimated by the proposed method are compared to those obtained by the temperature dilution method during right heart catheterization. A new index of cardiac performance is also presented: cardiac output as a percentage of total blood volume. This index is determined by a totally external count-based procedure.