Long-term prognostic value of myocardial perfusion scintigraphy in patients with suspected coronary artery disease: systematic review and meta-analysis

BACKGROUND: Long-term outcome of contemporary myocardial perfusion scintigraphy (MPS) has not been assessed systematically. OBJECTIVE: To evaluate the association between results of MPS and long-term outcomes for patients with suspected coronary artery disease (CAD). METHODS: Electronic databases were searched for Randomised controlled trials evaluating long-term outcome (≥12 months) of MPS in patients with suspected of CAD since year 2000. A meta-analysis adopting the random effects model was used to derive pooled estimates. The primary outcome was the composite of all-cause or cardiovascular mortality and non-fatal myocardial infarction as defined in individual trials, termed as major adverse cardiovascular event (MACE). Secondary outcome was all-cause or cardiovascular mortality. Positive MPS result was defined as reversible perfusion defect in any coronary artery territory. RESULTS: Four trials fulfilled the search criteria. A total of 1764 patient had MPS with a median follow-up of 35.7 months (range 17-57). The mean age was 59 years and 50% were male. Fifty-three per cent had hypertension, 43% had dyslipidaemia, 15% were current smokers and 61% had diabetes mellitus. The overall annual event rate was 1.42% for the composite MACE and 0.22% for all-cause or cardiovascular mortality. Compared with negative MPS results, positive MPS was associated with an increased risk of the composite MACE and all-cause or cardiovascular mortality with an annual event rate of 2.16% versus 0.66%, OR 2.71 (1.38, 5.32) and 0.34% versus 0.10%, OR 3.41 (1.44, 8.11), respectively. CONCLUSION: In this meta-analysis, reversible perfusion defect on MPS was associated with higher risk of composite MACE, and that of all-cause or cardiovascular mortality.