Ischemia burden on stress SPECT MPI predicts long-term outcomes after revascularization in stable coronary artery disease.

ABSTRACT

BACKGROUND: It is not entirely clear whether ischemia burden on stress single-photon emission computed tomography (SPECT) effectively identifies patients who have a long-term benefit from coronary revascularization. METHODS: The study population consisted of 719 patients with ischemia on stress SPECT. Early coronary revascularization was defined as percutaneous coronary intervention or coronary artery bypass grafting ≤90 days after SPECT. Patients who underwent late revascularization (>90 days after SPECT) were excluded (n = 164). RESULTS: Of the 538 patients (73% men, mean age 59.8 ± 11 years), 348 patients had low ischemia burden (<3 ischemic segments) and 190 patients had moderate to high ischemia burden (≥3 ischemic segments). A total of 76 patients underwent early revascularization. During a median follow-up of 12 years (range 4-17), 283 patients died of whom 125 due to cardiac causes. Early revascularization was beneficial on all-cause mortality (HR 0.46, 95% CI 0.30-0.46) and cardiac mortality (HR 0.54, 95% CI 0.29-0.99). CONCLUSIONS: Patients with myocardial ischemia on stress SPECT who underwent early revascularization had a lower all-cause mortality and cardiac mortality during long-term follow-up as compared to patients who received pharmacological therapy alone. This difference in long-term outcomes was mainly influenced by the survival benefit of early revascularization in the patients with moderate to high ischemia burden.