Regional left ventricular contraction abnormality during early systole in patients with angina pectoris. Assessment with radionuclide ventriculography

Augmentation of mortality risk discriminating power of left ventricular ejection fraction by measures of nonuniformity in systolic emptying on radionuclide ventriculography

Employing equilibrium-gated radionuclide ventriculography in the left anterior oblique view, six geometric models and five mathematic coefficients of nonuniformity in regional left ventricular emptying were tested for their relative mortality risk-stratifying power and capacity to augment the risk-discriminating potency of the continuous and dichotomized global ejection fraction. Radionuclide ventriculography was performed an average of 7.6 days after acute myocardial infarction. All geometric models significantly separated 20 normal subjects from 137 patients with recent infarction (p less than 0.001). Cumulative mortality data demonstrated that significant independent univariate dichotomizing potency and augmentation of the mortality risk-discriminating power of the global ejection fraction were provided by models of regional emptying that 1) conformed to coronary artery perfusion areas, 2) encompassed total ventricular counts, 3) expressed variability in regional relative to global ejection fraction, and 4) simulated a pattern of emptying directed toward the center of geometry of the left ventricle. The combination of a four quadrant geometric model with axes drawn 45 degrees above the horizontal and a coefficient of variation calculated as square root of sigma(GEF - REF)2/4 x 100/GEF (where GEF = global ejection fraction and REF = regional ejection fraction) proved to be optimal. This coefficient averaged 12.2% in normal subjects and 32.2% in patients with recent acute myocardial infarction (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Effort angina pectoris without electrocardiographic changes in coronary disease patients: correlations between scintigraphic and coronary angiographic findings

The absence of electrocardiographic changes during angina is an unusual occurrence. In 15 male patients with exercise-induced angina, the electrocardiogram failed to show the usual ischemic ST-T changes. The exercise thallium-201 myocardial imaging was employed as indicator of the ischemia and the results were correlated with coronary angiographic findings. The exercise thallium-201 myocardial imaging showed an exercise-induced reversible defect in 14 patients and a fixed defect in the remaining 1. Out of 15 patients, 13 had defects involving the infero-apical, posterior and postero-lateral segments. The coronary angiography, performed in all patients but 2, showed single-vessel coronary artery disease in 8 patients and double-vessel disease in 5. A significant circumflex or right coronary artery stenosis was found in all cases except 1; 2 patients had a coexistent left anterior descending coronary artery stenosis and 1 an isolated stenosis of this vessel. It is concluded that the myocardial scintigraphy is useful to assess the ischemic myocardial origin of chest pain in the absence of ST-T changes. The silence of the electrocardiogram might be due to the production of ischemia in not well explored areas, such as the inferior and posterior myocardial segments, and possibly to a smaller extension of ischemia.

Peak regional acceleration: a method to identify subtle regional ventricular dysfunction from gated blood pool scans at rest in patients with coronary artery disease

Peak regional acceleration images were obtained from gated blood pool scans at rest in 10 normal subjects, 16 patients who underwent cardiac catheterization for unstable angina or nontransmural infarction and were found to have normal ejection fraction and wall motion and 10 patients with prior infarction and regional dyssynergy. The second derivative of the time-activity curve of each pixel was generated and the maximal systolic value of the derivative for each pixel was displayed as a functional image (peak regional acceleration). Anterior and left anterior oblique views were evaluated for abnormalities and the presence and location of defects were correlated with the coronary anatomy. The scans from the 10 normal subjects were used to establish the normal range for regional second derivative values. Both gated blood pool scans and second derivative images showed regional abnormalities in all 10 patients with prior transmural infarction. Regional abnormalities were present in the second derivative images in the distribution of 17 of the 20 coronary arteries with greater than 50% stenosis; there were no regional abnormalities in the distribution of 7 of the 8 arteries with less than 50% stenosis. In addition, regional second derivative image abnormalities were present in 15 of the 16 patients with unstable angina and normal wall motion and global ejection fraction. These 16 patients showed regional abnormalities on second derivative images in the distribution of 19 of the 23 coronary arteries with significant stenosis and no regional abnormalities in the distribution of 21 of the 23 coronary arteries without significant stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)