Cardiovascular prognosis in patients with preserved left ventricular ejection fraction and no significant ischemia

Abstract

Background: Peripheral artery disease (PAD) and chronic kidney disease (CKD) are important cardiac risk factors, and stress myocardial perfusion imaging (MPI) is widely used as a diagnostic and predictive tool for coronary artery disease (CAD). We evaluated the usefulness of these risk factors for predicting cardiovascular events in patients with low cardiac risk assessed by stress MPI and echocardiography. Methods: We included 558 patients with suspected or confirmed CAD, a preserved left ventricular ejection fraction ≥50% on echocardiography, and no significant ischemia on stress MPI (summed difference score <2). Follow-up was for 46 months. Results: Cardiovascular events were observed in 37 patients (6.6%). Multivariate Cox regression analysis indicated that PAD (hazard ratio: 6.62,P<0.001), CKD (hazard ratio: 2.44, P=0.013), and history of CAD (hazard ratio: 2.67, P=0.003) were significant predictors of cardiovascular events. After 48 months’ follow-up, the event rate was significantly higher in patients with a history of CAD than in those without a history of CAD. Conclusion: In patients with preserved left ventricular ejection fraction and no significant myocardial ischemia, baseline characteristics such as PAD, CKD, and history of CAD can predict cardiac risk.