Abstract 16464: End Systolic Volume and Viability Assessed by Cardiac MRI Predicts Differential Survival in Patients With Severe Ischemic Cardiomyopathy Undergoing Revascularization vs. Medical Therapy: The Missing STITCH?
Introduction: End systolic volume index (ESVi) and myocardial scar burden (MSB) are independent predictor of mortality in ischemic cardiomyopathy (ICM). The STITCH trial did not include cardiac MRI in its assessment of viability and ESVi to predict outcomes with medical therapy vs. 90 day revascularization.
Purpose: In patients with severe ICM, we sought to assess the association of MSB, ESVi, and post-test revascularization with outcomes in severe ICM.
Methods: 335 patients with > 70% stenosis in ≥1 epicardial coronary artery (75% men, median age 64 years, median LV ejection fraction (EF) 22 %, median ESVi 109cc) underwent Delayed hyperenhancement-MRI between 2003-2007. Scar was defined as > 2 SD above normal myocardium. Scar/EF is a viability index defined as scar score/EF. Revascularization within 90 days after testing (REV) occurred in 168 patients and was modeled with logistic regression to develop a propensity score. Cox proportional hazards survival modeling of a composite end-point (CE; cardiac transplantation, all-cause mortality) was used to risk-adjust comparisons.
Results: Over a follow-up of up to 8 years[mean 5.5 years], 131 events occurred (126 deaths, 5 cardiac transplantations). Survival analysis revealed that after adjusting for prior CABG/PCI, sex, diabetes, age, use of CRT, ICD, mitral valve or aortic valve procedures, scar/EF (χ2 14.56, p = 0.007) and ESVi (χ2 8.7, p = 0.012) were independent predictors of CE. An interaction between REV and ESVi was present indicating enhanced survival with REV with increasing ESVi (Figure 1). Scar/EF interacts with ESVi and predicts treatment outcome through this interaction.
Conclusions: ESVi and viability index, scar/EF, provide independent, incremental prognostic value in patients with severe ICM. ESVi identifies differential survival with 90 day revascularization vs medical therapy. Scar/EF provided further differential prognostic value based on treatment type through its interaction with ESVi.
- © 2011 by American Heart Association, Inc.