Impaired Left Atrial Reservoir Strain Causes Exercise-Induced Pulmonary Hypertension in Patients With Preserved Left Ventricular Ejection Fraction.

Objective: Exercise-induced pulmonary hypertension (EIPH), assessed using exercise stress echocardiography (ESE), is important in diagnosing early stage of heart failure (HF) with preserved ejection fraction (EF) and affects exercise tolerance and prognosis. Left atrial (LA) reservoir strain, which reflects the left ventricular filling pressure, is an associated factor with HF. This study aimed to investigate the association between the LA reservoir strain at rest and EIPH.

Methods: This retrospective analysis included 188 participants with a left ventricular EF ≥ 50% who underwent ESE. EIPH was defined as a peak tricuspid regurgitation (TR) pressure gradient >50 mm Hg. HF events (HF hospitalization or diuretic use with brain natriuretic peptide ≥100 pg/mL) were evaluated in patients with ≥3 months follow-up.

Results: Thirty-four (18.1%) patients were diagnosed with EIPH. LA reservoir strain at rest with an optimal cutoff value of 21% identified patients, with 73% sensitivity and 59% specificity. The multivariate logistic regression analysis indicated that LA reservoir strain was independently associated with EIPH. Furthermore, adding LA reservoir strain to the TR-velocity significantly improved EIPH discrimination. During a median follow-up period of 336 days, 29 patients (21.6%) experienced HF events. The hazard ratio for HF events in patients with LA reservoir strain ≤21% was 4.04 after adjusting for age and HFA-PEFF score (95% confidence interval, 1.29-12.7).

Conclusions: LA reservoir strain at rest was associated with EIPH and HF events in patients with preserved EF, suggesting that impaired LA reservoir strain could increase the risk of HF.