| Abstract: | To assess the cardiac response to various exercise in ischemic heart disease (IHD), left ventricular function was continuously measured with an ambulatory ventricular monitor (VEST) in 3 normal subjects and 15 IHD patients. Treadmill exercise (early stage (E1), end stage (E2) and recovery standing state (RE], walking (WK) and climbing stairs (CS), was used for exercise. 15 IHD patients were divided into 4 groups by the LVEF response to treadmill exercise. In group 1 (G1), LVEF increased gradually at stage 1 and became plateau from stage 2 to end stage like normal group. In group 2 (G2), LVEF increased at stage 1 and became plateau from stage 2 but decreased from maximal EF more than 5% at end stage. In group 3 (G3), LVEF increased only at stage 1 and decreased immediately after stage 1 to end stage. The decrease of LVEF at end stage from standing was more than 5%. In group 4 (G4), LVEF decreased at stage 1 and became minimum at end stage. This grouping was well related to thallium redistribution (Tl RD) score and coronary arteriography (CAG) score. We could predict the severity of coronary artery disease from this grouping because all group 3 or 4 patients had severe coronary artery disease. VEST was useful for the evaluation for the tolerance to daily activities. Group 1, 2 and 3 tolerated daily activities while group 4 could not always. The degree of the increase in cardiac output during ischemia evaluated by VEST may be one of the useful index of the tolerance to exercise. In conclusion VEST was very useful for evaluating cardiac capacity of ischemic heart disease patients during various exercise. |
