[Comparison of the hand grip apex cardiography test and stress ECG for detection of patients with coronary heart disease]

Abstract

It has been recently demonstrated by many authors that diastolic abnormalities of the left ventricle are the earliest mechanical manifestations of myocardial ischemia preceding both the ECG changes and angina pectoris. Recently, we have shown that using a handgrip-apexcardiographic test (HAT), one can accurately assess exercise-induced abnormalities of diastolic function in patients with angina pectoris or silent ischemia. Aim of this study is to compare the clinical value of HAT and stress-ECG in patients with prospectively documented coronary artery disease (CAD). Subject and methods 275 healthy volunteers (208 men) and 52 patients (47 men) with known (18 with prior infarction) or suspected CAD were examined. HAT and stress-ECG were performed within one month before heart catheterization. There were 17 single, 17 double, and 18 triple vessel disease patients, who showed no large dyskinesias and no wall aneurysms on angiography. Apexcardiogram (ACG) was recorded simultaneously with phonocardiogram and ECG before, during and after a low level (40% of maximal voluntary contraction) isometric stress of short duration (two minutes). As indices of diastolic function served the relative A wave to total (A/H) and to diastolic deflection (A/D) as well as the total apexcardiographic relaxation time (TART) from the onset of the aortic component of the second heart sound (A2) to the protodiastolic nadir of ACG and the TART index (TARTI) given by dividing the square root of the duration of diastolic length with TART (TARTI = square root of A2-C/TART, whereas C is the apexcardiographic onset of the systolic upstroke). Furthermore, the combined index of diastolic function DATI (diastolic amplitude time index) was calculated (DATI = TARTI/[A/D]). A pathologic or positive HAT was defined by the presence of at least one of the following recently introduced criteria: 1. A/H during and/or after handgrip > 21%, 2. TART during handgrip > TART at rest > 143 ms and/or TARTI during handgrip < 0.14, or 3. DATI during handgrip < 0.27; these limits representing the largest and lowest individual values in the controls. Complications occurred less often during HAT than during stress-ECG (angina pectoris: 4% and 25%, ventricular extrasystoles 6% and 16%, respectively). Changes of diastolic apexcardiographic indices As evident in Table 1, in the normals there were only slight, although significant, changes of TART, TARTI, DATI and A/D during handgrip; whereas A/H showed no significant changes.(ABSTRACT TRUNCATED AT 400 WORDS)