[Effect of collateral circulation on the progression of left ventricular dilatation after myocardial infarct].

48 patients (aged 50.5 +/- 8.5 years) with proven acute first myocardial infarction underwent coronary angiography 1.6 weeks to 4 years (mean 13.3 weeks) after infarction. No reperfusion interventions were performed, no patient received a longterm therapy with diuretics, glycosides, beta-blockers or ACE-inhibitors. In accordance with the angiographic results, patients were divided into two groups: 25 patients demonstrated a proximal occlusion of one major coronary artery with retrograde contrast filling by non-compromised collaterals; in 23 patients no collateral filling of the distal vessel segment was visible. The contralateral coronary arteries and corresponding LV wall segments were normal. Age, sex distribution, localization of the infarction and infarct related vessel and intraventricular pressures (LVSP = 121.2 +/- 13.5 vs. 122.1 +/- 18.9 mm Hg; LVEDP = 13.1 +/- 5.2 vs. 11.9 +/- 4.1 mm Hg) were not significantly different between both groups. Between both groups patients were compared in whom angiography was performed less than 4, 4-6, and greater than 6 weeks after infarction. In addition, occlusion of the LAD was compared with LCX- and RCA-obstructions both with and without collaterals. Patients with collaterals revealed no significant time dependent changes of the endsystolic (48.1 +/- 11.3; 56.7 +/- 20.5; 43.8 +/- 16.2 ml/m2), enddiastolic (114.9 +/- 30.6; 121.3 +/- 10.8; 99.0 +/- 22.5 ml/m2) volumes and ejection fraction (57.7 +/- 6.5; 53.9 +/- 13.5; 56.4 +/- 9.9%). In contrast in patients without collaterals ESVI increased significantly (44.2 +/- 16.2; 50.8 +/- 17.5; 68.3 +/- 30.9 ml/m2) by an exponential function (y = 28.11 e0.13x; r2 = 0.99; p less than 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)