Left atrial volume index during rest and stress echocardiography predicts survival in patients with chronic coronary syndrome

Background The left atrial volume index (LAVI) acts as a barometer of the heart and a prognostic marker in chronic coronary syndromes (CCS). An excess dilation during stress is an ancillary marker of left ventricular diastolic and systolic dysfunction. Aim This study sought to assess the prognostic value of dilated LA volume at rest and during stress. Methods In a prospective, multicenter, observational study design, we enrolled 8458 patients [age = 64± 12 years; 60% male] with known or suspected CCS. All patients underwent stress echocardiography (SE) with exercise (n=3771, 59.3%), dobutamine (n=776, 12.2%), or vasodilators (n=1811, 28.5%). We assessed regional wall motion abnormality (RWMA) and LAVI at rest and peak stress in all patients. LAVI ≥34 ml/m2 at rest or increase ≥20% of baseline during stress was considered abnormal. The outcome measure was all-cause death. Results LAVI at peak stress was feasible in 6358 (75.2%), higher with vasodilators (1811/1973: 91.8%), and lower with exercise (3771/5081, 74.2%) and dobutamine (776/1398, 55.5%). LAVI rest was abnormal in 2353 patients (27.8%) and LAVI stress in 818 patients (12.9%). Induced RWMA were present in 935 patients (14.7%), and were less prevalent in patients with normal rest and stress LAVI (Group 1, 473/3958, 12.0%) compared to those with abnormal LAVI at rest and/or stress (Group 2, 462/2400, 19.3%, p<0.001). Follow-up data were obtained in 3541 patients. During a median follow-up of 20 months, 86 all-cause deaths (2.4%) occurred. The death rate among 100 persons/year was higher in patients with abnormal LAVI response (Group 1= 0.58% vs. Group 2= 1.80%, p<0.001): Figure 1. In multivariable analysis, abnormal resting and/or stress LAVI was independently associated with mortality (HR 1.82, 95% CI 1.17-2.85; p=0.008), together with inducible RMWA (HR 1.80, 95% CI 1.04-3.13; p=0.036), resting ejection fraction (HR 0.96, 95% CI 0.94-0.97; p<0.001), and age (HR 1.02, 95% CI 1.01-1.04; p=0.047). The death rate among 100 persons/year was lowest in LAVI-/RWMA- (0.53 deaths per 100 p-yrs), intermediate in LAVI-/RWMA+ and LAVI-/RWMA+, and highest in LAVI+/RWMA+ (3.91 deaths per 100 p-years, p<0.001): Figure 2. Conclusions In CCS, rest and stress LA dilation during SE help refine survival prediction provided by inducible RWMA.