[Indices of left ventricular diastole in patients with unstable angina and angiographically documented collateral circulation].

23 patients (20 males, 3 females) aged 26-62 (mean 45.9 +/- 9.9) with unstable angina underwent the study to evaluate the effect of collateral circulation vessels (CCV) on left ventricular diastole. There was no evidence of myocardial infarction in the past and ejection fraction was normal (EF greater than 60%). At least one branch of left coronary artery was significantly stenosed (more than 75% of a vessel lumen). Patients were divided into two groups: group I -- with CCV, group II -- without CCV. Obtained data were compared between these groups and with the control group (K) consisted of 10 persons. CCV were only observed if a coronary artery was occluded or subtotally stenosed. When a coronary artery was occluded, CCV could prevent myocardial infarction. Time constant (T) prolongation (43.6 +/- 10.8 vs 32 58 +/- 7.9 ms, p less than 0.05 for groups I and K and 49.31 +/- 18.8 vs 32.58 +/- 7.9 ms, p less than 0.02 for groups II and K) testifies to relaxation slowing down in patients with unstable angina, which indicates left ventricular myocardial ischemia. Lack of CCV influence on time constant T (43.6 +/- 10.8 vs 49.31 +/- 18.8 ms, p less than 0.5) as well as remaining left ventricular diastolic parameters (EDVI, EDP) seems that CCV were an insufficient source of a blood flow to myocardium supplied by a stenosed artery.