Abstract 3681: Prophylactic Sodium Nitroprusside Administration in Saphenous Vein Graft Intervention Reduces Post-procedural Cardiac Marker Elevation
Introduction: Saphenous vein graft (SVG) PCIs are associated with an increased rate of post-procedural cardiac enzyme elevations.
Hypothesis: Prophylactic administration of sodium nitroprusside vasodilates the microvasculature and reduces post-procedural myonecrosis during SVG PCIs.
Methods: The cases consisted of 64 consecutive patients undergoing SVG PCIs without distal protection devices and with normal pre-procedural cardiac enzymes who received prophylactic intragraft nitroprusside via the guiding catheter before initial device activation. For each case, 2 control patients were selected in reverse chronologic order from an SVG PCI database. The 128 controls were matched for stent use, thromboatherectomy device use, pre-TIMI flow in the graft and clinical presentation. Cardiac enzymes were obtained at baseline and serially at 6 to 8 hour intervals post PCI.
Results: Mean patient age was 66±10 years. Stent use was 95.3% and thromboatherectomy use was 3.1% in both groups (p=ns). TIMI < 3 flow was present in 26.6% of cases and in 24.2% of controls (p=ns). Thrombus or filling defect was present in 20.3% of cases and in 19.5% of controls (p=ns). The pre PCI mean diameter stenosis was 78.3±12.6% in the cases and 79.0±13.4% in the controls (p=ns). Glycoprotein 2b3a inhibitors were used in 64% of cases and 52% of controls (p=ns). The mean initial dose of nitroprusside was 130±77 microgm with 2.9±1.2 doses given per graft. Post PCI CK-MB elevation > 3 and > 5 times the upper limit of normal occurred respectively in 6.3% of cases vs 16.4% of controls (p=0.049) and in 1.6% of cases vs 10.9% of controls (p=0.022). Instent restenosis, thrombus presence, TIMI < 3 flow, procedural indication, stent deployment, and plavix and glycoprotein 2b3a use were not significant univariate predictors of CK-MB elevation > 3 times upper limit of normal. In multivariate binary logistic regression analysis, nipride administration was the only significant predictor of post-procedural CK-MB elevation with its administration predicting a lower rate of post-procedural enzyme elevation.
Conclusion: Prophylactic administration nitroprusside during saphenous vein graft interventions results in a lower rate and magnitude of post-procedural cardiac enzyme elevation.