Left atrial strain improves estimation of filling pressures in heart failure: a simultaneous echocardiographic and...

Left ventricular diastolic pressure estimation is essential for characterization of heart failure (HF). Patients with normal resting left atrial (LA) pressures (LAP), but steep LAP elevation on exertion, pose a particular diagnostic challenge. Current recommendations on echocardiographic LAP estimation have limited accuracy. Our aim was to investigate whether LA mechanical alterations assessed by LA strain (LA-GS) can contribute to non-invasive LAP diagnostics.

Simultaneous echocardiographic and right heart catheterization (RHC) data at rest and during exercise was analyzed in 164 prospectively enrolled patients, referred for RHC due to HF symptoms. 56% had preserved ejection fraction (pEF). At rest, 97 patients displayed elevated mean pulmonary arterial wedge pressure (PAWP_M); further 32 patients had normal resting, but elevated PAWP_M during exercise. LA-GS demonstrated a stronger relationship with resting PAWP_M (r = - 0.61, p < 0.001) than any of the indices (E/e', LAVi, TRV_max) incorporated in the currently recommended diagnostic algorithm. The diagnostic ability of LA-GS for detecting elevated resting PAWP_M (AUC: 0.80, p < 0.001) outperformed that of the recommended algorithm (AUC: 0.69). Importantly, resting LA-GS performed even better in identifying patients with pathological PAWP_M either at rest or during stress (AUC: 0.90, p < 0.001), whereas the diagnostic potential of the current algorithm was modest and limited to pEF patients (AUC = 0.72). Finally, among the non-invasive indices, LA-GS entailed the strongest prognostic value for death or heart transplantation (OR: 2.7; p < 0.05).

LA-GS comprises a robust method for PAWP_M assessment at rest. More importantly, it reliably discerns pathological PAWP_M rise on exertion despite normal resting pressures.