Predictors and sequelae of distal embolization during saphenous vein graft intervention from the CAVEAT-II trial

Background: The purpose of this study was to identify the predictors and sequelae of distal embolization from a multicenter, randomized trial of saphenous vein graft intervention. The CAVEAT-II trial demonstrated that saphenous vein graft directional coronary atherectomy (DCA) was associated with greater angiographic success and less need for repeat intervention compared with percutaneous transluminal coronary angioplasty (PTCA) but at the cost of more acute complications-notably distal embolization. Methods and Results: In CAVEAT-II, 305 patients were randomly assigned to DCA (149 patients) or PTCA (156 patients) for lesions with >60% diameter stenosis in vein grafts ≥3 mm in diameter. Distal embolization occurred in 20 patterns (13.4%) assigned to DCA and 8 patients (5.1%) assigned to PTCA (P=.011). Independent predictors of distal embolization were use of DCA (71% in distal embolization patients versus 47% in patients without distal embolization, P=.011) and presence of thrombus (39% in distal embolization patients versus 14% in patients without distal embolization, P<.00). In-hospital adverse events were more frequent after distal embolization: 71% versus 20%, odds ratio plus (95% confidence intervals) 9.87 (4.65, 20.94). At 12-month follow- up, adverse event rates were also higher in patients with distal embolization (odds ratio, 3.05 [1.95, 4.76]). Conclusions: In this first prospective multicenter trial of saphenous vein graft intervention, distal embolization was more common after DCA than PTCA and in lesions containing thrombus. It also was associated with worse in-hospital and 12-month outcomes. The risk and sequelae of distal embolization should be considered when choosing a treatment strategy for vein graft disease.