Prognostic significance of left atrial reservoir strain during exercise in patients with heart failure
Background This study aimed to evaluate the association of peak exercise left atrial (LA) reservoir strain with clinical outcomes in patients with heart failure (HF), and the prognostic value across HF phenotypes. Methods We enrolled 150 patients with HF (age 67 ± 15 years, 61% males) who underwent exercise stress echocardiography. LA reservoir strain at rest and peak workload were evaluated using the speckle-tracking echocardiography. The endpoint was a composite of cardiovascular death or hospitalization for HF. Results During a median follow-up of 1.1 years (interquartile range 0.7–2.4 years), 49 patients experienced events. Patients were categorized into two groups on the basis of the median value of LA reservoir strain at peak workload of 16.7%. Kaplan–Meier curves showed that patients with low LA reservoir strain at peak workload had a higher event rate than those with high LA reservoir strain (log-rank test, P < 0.001). LA reservoir strain at peak workload was independently associated with events (hazard ratio: 5.57, 95% confidence intervals: 2.74–11.3, P < 0.001), and provided the incremental prognostic value over clinical factors. When analyzed according to HF phenotype, LA reservoir strain at peak workload was significantly associated with events in both patients with HFpEF and those with HFrEF, with a significant interaction between HF phenotype and LA reservoir strain at peak workload. Conclusion LA reservoir strain at peak workload has prognostic value for adverse outcomes in both HFpEF and HFrEF.