[Ambulatory monitoring of left ventricular function in patients with ischemic heart disease: effects of coronary revascularization]. / Monitoraggio ambulatoriale della funzione ventricolare sinistra (VEST) in pazienti con cardiopatia ischemica: effetti della rivascolarizzazione coronarica.

The aim of this study was to assess the efficacy of coronary artery bypass using an ambulatory radionuclide monitoring system of left ventricular function (VEST) during daily activities in patients with previous myocardial infarction and coronary artery disease. Ten patients with previous myocardial infarction, clinical evidence of residual angina and angiocardiographically proven coronary artery disease of at least two epicardial vessels were studied by VEST 8 +/- 2 days before and 15 +/- 3 days after surgical myocardial revascularization. VEST allows to monitor both left ventricular function and 2 ECG leads. During the radionuclide monitoring (at least 60 min) all patients underwent handgrip test (compression of a dynamometer for 2 min at the 75% of maximal capacity), a mental stress (arithmetic operation consisting in subtracting 17 from 17,000 for 4 min), walking (140 yards) and climbing stairs (8 flights). No significant changes in left ventricular function during mental stress and handgrip both before and after the surgical procedure were observed. In the preoperative evaluation, walking induced a significantly increase in heart rate from rest to peak exercise (73 +/- 13 versus 79 +/- 11 b/min, respectively; p < 0.01). After coronary artery bypass, heart rate (rest: 92 +/- 18 b/min, effort: 98 +/- 19 b/min; p < 0.01), ejection fraction (rest: 47 +/- 8%, effort: 53 +/- 10%; p < 0.01), cardiac output (rest: 43 +/- 8 edv/min, effort: 51 +/- 11 edv/min, p < 0.01), and stroke volume (rest: 47 +/- 9%, effort: 53 +/- 9%; p < 0.01) increased at maximal effort compared to the control conditions.(ABSTRACT TRUNCATED AT 250 WORDS)