Abstract 19392: A Landmark Analysis of 30-day Mortality after Coronary Artery Bypass Surgery in Patients with Ischemic Heart Failure: Results of the Surgical Treatment for Ischemic Heart Failure (STICH) Trial
Background: Among patients (pts) with coronary artery disease (CAD) who are candidates for coronary artery bypass graft surgery (CABG), a reduced ejection fraction (EF) identifies a high-risk group. The profile of pre-operative, intra-operative and post-operative factors contributing to 30 day (d) mortality in pts with low EF undergoing CABG has not been well characterized. Methods: The STICH trial enrolled 2136 pts with CAD amenable to CABG with an LVEF < 35% who were treated with medical therapy (MED) alone, MED with CABG, or with MED plus CABG and surgical ventricular resconstruction (SVR). Multivariable logistic regression models utilizing extensive baseline, intra-operative and post-operative care variables were developed to determine factors associated with mortality at 30d in a landmark analysis among pts surviving the first 36 hours (h). Results: Among those enrolled, 1460 pts received CABG; 673 (46.1%) on pump, 160 (11.0%) off pump, 132 (9.0%) with a mitral valve procedure (MVR), 393 (26.9%) with SVR, and 102 (7.0%) received CABG with SVR and MVR. Mortality in the operating room (OR) was 0.3 %, within the first 36h was 1.0%, and at 30d was 5.1%. The rate of in-hospital acute myocardial infarction was 0.8%, stroke 1.6%, mediastinitis 1.7%, worsening renal insufficiency 8.4%, and return to OR was 6.9%. Inotropes were used in 43.6% and intra-aortic balloon pump in 18.6%. At 36h, 148 pts (10.2%) remained intubated. Among pts who survived to 36h, a robust multivariable model (Table, c-statistic 0.89) was developed to predict 30d mortality. A prolonged intubation time (>36h) was the strongest marker of 30d mortality (odds ratio 7.4, 95% CI 3.8, 14.5, p<0.0001). Conclusions: Among pts with ischemic heart failure, CABG can be performed with a low rate of complications and intra-operative mortality. Prolonged intubation time (>36h) after CABG is an integrated clincal marker that may serve to identify those pts with the least likelihood of survival to 30d.
Outcomes for Patients With ST-Elevation Myocardial Infarction in Hospitals With and Without Onsite Coronary Artery Bypass Graft Surgery
Background— The benefit of primary percutaneous coronary interventions (P-PCI) for patients with ST-elevation myocardial infarction (STEMI) has been well documented. However, controversy still exists as to whether PCI should be expanded to hospitals without coronary artery bypass graft surgery. Methods and Results— Patients who were discharged after PCI for STEMI between January 1, 2003, and December 12, 2006, in P-PCI centers (hospitals with no coronary artery bypass graft surgery, and PCI only for patients with STEMI) were propensity matched with patients in full service centers, and mortality and subsequent revascularization rates were compared. For patients undergoing PCI, there were no differences for in-hospital/30-day mortality (2.3% for P-PCI centers versus 1.9% for full service centers [ P =0.40]), emergency coronary artery bypass graft surgery immediately after PCI (0.06% versus 0.35%, P =0.06), 3-year mortality (7.1% versus 5.9%, P =0.07), or 3-year subsequent revascularization (23.8% versus 21.5%, P =0.52). P-PCI centers had a lower same/next day coronary artery bypass graft rate (0.23% versus 0.69%, P =0.046) and higher repeat target vessel PCI rates (12.1% versus 9.0%, P =0.003). For patients with STEMI who did not undergo PCI, P-PCI centers had higher in-hospital mortality (28.5% versus 22.3%; adjusted odds ratio, 1.38; 95% CI, 1.10 to 1.75). Conclusions— No differences between P-PCI centers and full service centers were found in in-hospital/30-day mortality, the need for emergency surgery, 3-year mortality or subsequent revascularization, but P-PCI centers had higher repeat target vessel PCI rates and higher mortality rates for patients who did not undergo PCI. P-PCI centers should be monitored closely, including the monitoring of patients with STEMI who did not undergo PCI.
Volume-Outcome Relationships for Percutaneous Coronary Interventions in the Stent Era
Background— Most studies that are the basis of recommended volume thresholds for percutaneous coronary interventions (PCIs) predate the routine use of stent placement. Methods and Results— Data from New York’s Percutaneous Coronary Interventions Reporting System in 1998 to 2000 (n=107 713) were used to examine the impact of annual hospital volume and annual operator volume on in-hospital mortality, same-day coronary artery bypass graft (CABG) surgery, and same-stay CABG surgery after adjustment for differences in patients’ severity of illness. For a hospital-volume threshold of 400, the odds ratios for low-volume hospitals versus high-volume hospitals were 1.98 (95% CI, 1.17, 3.35) for in-hospital mortality, 2.07 (95% CI, 1.36, 3.15) for same-day CABG surgery, and 1.51 (95% CI, 1.03, 2.21) for same-stay CABG surgery. For an operator-volume threshold of 75, the odds ratios for low-volume versus high-volume operators were 1.65 (95% CI, 1.05, 2.60) for same-day CABG surgery and 1.55 (95% CI, 1.10, 2.18) for same-stay CABG surgery. Operator volume was not significantly associated with mortality. Also, for hospital volumes below 400 and operator volumes below 75, the respective odds of mortality, same-day CABG surgery, and same-stay CABG surgery were 5.92, 4.02, and 3.92 times the odds for hospital volumes of 400 or higher and operator volumes of 75 or higher. Conclusions— Higher-volume operators and hospitals continue to experience lower risk-adjusted PCI outcome rates.