EMERGENCY CORONARY STENTING WITH THE PALMAZ-SCHATZ STENT FOR FAILED TRANSLUMINAL CORONARY ANGIOPLASTY - RESULTS OF A LEARNING PHASE

This study describes initial results of Palmaz-Schatz stent implantation in our department to restore and maintain vessel patency in 52 patients with obstructive dissection, defined as an intraluminal filling defect with coronary flow impairment after percutaneous transluminal coronary angioplasty (PTCA). The majority of patients (62%) underwent PTCA for unstable angina (n = 28), defined as angina at rest with documented ST segment changes resistant to nitrates, or acute myocardial infarction (n = 4). In six patients (11%) the stent could not be delivered. Seven of the remaining 46 patients (15%) had coronary artery bypass surgery performed because of increased risk for subacute stent occlusion, residual thrombosis, residual obstruction near the stent, coronary artery diameter less than 3.0 mm, or multiple and overlapping stents. One patient (3%) died in hospital from intracranial bleeding. Nine patients (23%) had subacute stent occlusion, retrospectively unpredictable in four patients. Nine of 29 patients (29%) with an uncomplicated clinical course after stenting had angiographic restenosis at a mean follow-up of 6.0 +/- 1.4 months (range 12 days to 8.3 months). Two patients (7%) died 3 months after successful stenting: one patient because of stent thrombosis after stopping warfarin before an abdominal operation and one patient after acute vascular surgery for late traumatic groin bleeding. Of the 39 medically treated patients with a stent, three (8%) had major bleeding complications. It is concluded that stent implantation is feasible in most patients with obstructive dissection after PTCA. After successful stent delivery, coronary flow is temporarily restored. However, during this early experience with emergency stenting, it was shown that non-surgical treatment of these patients resulted in substantial subacute stent occlusion rates. Accordingly, stabilized patients should be considered as a high-risk population for subacute stent thrombosis, needing careful monitoring of anticoagulant treatment and ambulation. Semielective bypass surgery after emergency stenting may be the treatment of choice. With a combination of an optimal angiographic result and an optimal clinical infrastructure and patient management, a more conservative treatment after emergency stent implantation may be advocated.