Does ischemic burden on stress testing influence patient survival in subjects with known severe multi-vessel CAD?

Background: Ischemic burden observed during stress testing has been postulated to predict prognosis irrespective of anatomic atherosclerotic burden observed on angiography. However, it is not known if the stress test result influences the long-term prognosis of subjects with diffuse coronary artery disease. We sought to determine the prognostic importance of stress test false negativity amongst patients with severe multi-vessel coronary artery disease (CAD) undergoing stress testing in the previous decade. Methods: We selected subjects from the dates of 1/1/2000 to 12/31/2005 who underwent a nuclear stress test (MPI) or stress echocardiogram (SE) within six months of a coronary angiogram demonstrating severe, multi-vessel CAD. We excluded those with a prior MI, PCI, CABG, resting wall motion abnormality, or perfusion defect at rest. Determination of patient death during the followup period was performed using the U.S. social security index. Results: 139 subjects (MPI 81, SE 58) were studied; stress tests were positive for ischemia in 80%. Rates of death were similar at 1 year (MPI 9%, SE 5%, p-value 0.44), 5 years (MPI 20%, SE 14%, p-value 0.36) and 10 years (MPI 30%, SE 26%, p-value 0.63). Using multivariate analysis, mortality at each time period was not affected by stress test positivity. Conclusion: Amongst subjects with diffuse and severe atherosclerosis with preserved ventricular function, ischemic burden on stress testing did not influence short or long-term survival