[Holter electrocardiography before and after coronary angioplasty. Angiographic correlation after 24 hours and 6 months].

Myocardial ischaemia was searched for by Holter monitoring before and after coronary angioplasty with primary success in 31 patients. Control angiography was performed at 24 hours and 6 months after angioplasty. Twelve patients had signs of myocardial ischaemia before angioplasty (cumulated ischaemia: 743 minutes). The degree of coronary stenosis was 92 +/- 6% before angioplasty, 25 +/- 17% immediately after the dilatation increasing to 34 +/- 25% at the 24th hour (p less than 0.002). Despite successful angioplasty myocardial ischaemia persisted in 6 patients (cumulated ischaemia: 184 minutes) and was silent in 5 of the 6 cases. In these 6 cases, control angiography at 24 hours showed either a dissection (n = 4) or a filling defect (n = 2). The angiographic outcome of the postangioplasty stenosis and at 24 hours was the same in Group I without restenosis (25 +/- 14% versus 33 +/- 22%) as in Group II with restenosis (25 +/- 22% versus 37 +/- 30%). In Group I, the degradation of the result at 24 hours was reversible at 6 months (33 +/- 22% vs 23 +/- 14%). After angiographic success, postangioplasty ischaemia present in 20% of cases was frequently silent. No correlation was observed with restenosis at 6 months which raises the possibility of a reversible microthrombotic etiology. These results justify antiaggregant and anticoagulant therapy in the 48 hours following angioplasty.