Cardiovascular event risk estimated after coronary revascularization and optimal medical therapy: J-ACCESS4 prognostic study

BACKGROUND: An assessment of cardiac events and survival using quantitative gated myocardial single-photon emission computed tomography (SPECT) (J-ACCESS) associated several risk factors with cardiac events in Japan. The clinical course after revascularization and/or optimal medical therapy (OMT) was followed in patients with coronary artery disease (CAD) at moderate-to-high risk estimated by software incorporating the J-ACCESS risk model. The present study aimed to determine the relevance of changes in estimated risk to outcomes of these therapies. METHODS: This study included 494 patients with possible or definite CAD who underwent initial pharmacological stress (99m)Tc-tetrofosmin myocardial perfusion SPECT (MPS) before and eight months after therapy. Major cardiac event risk during 3 years of follow-up was calculated using an equation based on that in the J-ACCESS study. Patients with ≥ 10% cardiac event risk estimated at the first MPS (n = 31) were analyzed and followed up for at least 1 year. RESULTS: Estimated risk was reduced by ≥ 5% in 14 patients (45%) after therapy. During a follow-up period of 22.1 ± 6.7 months, one patient without such reduction had a major cardiac event. Mean %summed stress scores significantly decreased from baseline to follow-up in patients with and without risk reduction. Left ventricular ejection fraction (LVEF [%]) at rest was significantly increased at the second, compared with the first MPS between patients with, than without risk reduction (57 ± 17 vs. 45 ± 16%, p = 0.001 and 50 ± 11 vs. 49 ± 9%, p = 0.953, respectively). CONCLUSIONS: A reduction in cardiac ischemia and an increase in LVEF by revascularization and/or OMT were necessary to avoid cardiac events among patients with moderate-to-high estimated risk, and changes in event risk were quantifiable.