Determinants of stent restenosis in chronic coronary occlusions assessed by intracoronary ultrasound

Chronic coronary occlusions have a high recurrence rate that can be reduced by stenting, but this rate remains higher than in nonocclusive lesions. To analyze possible determinants of restenosis in these lesions, intracoronar y ultrasound was performed during the recanalization procedure. A chronic c oronary occlusion of greater than or equal to 1 month duration (range 1 to 33 months; median 3.3) was successfully recanalized in 41 patients. Quantit ative ultrasound analysis was performed before and after stent placement, w ith measurement of the luminal area, the extent of the plaque burden at the site proximal and distal to the occlusion, and within the occlusion and th e subsequent stent, The degree of compensatory enlargement of the coronary artery within the occlusion was determined by comparing the average of the total vessel area of the proximal and distal reference with the lesion site . Early reocclusion (subacute scent thrombosis) was observed in 1 patient ( 2.4%). The angiographic control after 6 months showed restenosis in 9 patie nts with 1 late reocclusion, The overall recurrence rate was 24%. There was no difference in clinical and procedural characteristics between lesions w ith restenosis and without restenosis. The latter had a larger minimum sten t area (7.59 +/- 1.96 mm(2) vs 5.71 +/- 0.90 mm(2); p < 0.01), and there wa s evidence for more compensatory vessel enlargement in lesions without rest enosis, Thus, infracoronary ultrasound showed that a smaller minimum stent area was a major predictor of angiographic restenosis, and it occurred more often in occlusions without compensatory vessel enlargement, (C)1999 by Ex cerpta Medica, Inc.