Handgrip-apexcardiographic test: a new mode of detecting patients with silent exercise-induced myocardial ischemia.

There are no simple noninvasive stress tests for detecting silent myocardial ischemia by assessing left ventricular (LV) diastolic abnormalities which are known to occur early on the onset of every ischemic episode. It has been proved that the LV apexcardiogram (ACG) reflects the LV pressure curve in early and late diastole and can be recorded during isometric handgrip (HG) exercise. To determine the clinical validity of HG-ACG-Test (HAT) in identifying patients with silent ischemia, 16 patients (8 with prior infarction) with angiographically documented coronary artery disease, positive treadmill electrocardiographic test and without symptoms were examined. According to the largest and lowest individual values in 253 healthy volunteers, the positivity of HAT was defined by the presence of at least one of the criteria: 1) The relative A-wave to total height of ACG during or/and after HG greater than 21%. 2) The total ACG relaxation time (TART) during HG longer than at rest and also longer than 143 ms or/and the heart rate corrected TART during HG less than 0.14, or 3) the combined index of overall diastolic function DATI (= diastolic amplitude time index) during HG less than 0.27. Based on this definition 14/16 (sensitivity: 88%) patients showed a positive test result. It is concluded that, using new definitions of positivity, HAT shows a high sensitivity for detecting patients with proved silent ischemia providing, thus, providing a new simple clinical tool for the identification of these patients.