Left atrial function in heart failure with preserved ejection fraction: a systematic review and meta-analysis

Aims: Left atrial (LA) mechanical function may play a significant role in the development and progression of heart failure with preserved ejection fraction (HFpEF). We performed a systematic review and meta-analysis to evaluate association of impaired LA function with outcomes in HFpEF. Methods and results: Multiple databases were searched for original studies measuring different phases of LA function in HFpEF patients. Comparative LA function between HFpEF patients and healthy controls was assessed by pooling weighted mean differences (WMD). Adjusted hazard ratios (HRs) with 95% confidence intervals were pooled to evaluate the prognostic utility of LA function. Twenty-two studies (2 trials, 20 observational) comprising 1974 HFpEF patients and 751 healthy controls were included. HFpEF patients had decreased LA reservoir [WMD = −12.21% (−15.47, −8.95); P < 0.001], LA conduit [WMD = −5.68% (−8.56, −2.79); P < 0.001], and pump [WMD = −11.07% (−14.81, −7.34); P < 0.001] emptying fractions compared with controls. LA reservoir [WMD = −13.38% (−16.07, −10.68); P < 0.001], conduit [WMD = −4.09% (−6.77, −1.42); P = 0.003], and pump [WMD = −3.53% (−4.47, −2.59); P < 0.001] strains were also significantly lower in HFpEF patients. Decreased LA reservoir strain [HR 1.24 (1.02, 1.50); P = 0.03] was significantly associated with risk of composite all-cause mortality or heart failure hospitalization. Conclusions: Impaired LA function appears to have diagnostic and prognostic value in HFpEF, but whether indices of LA function truly refine discrimination for diagnosis or prognosis remains to be fully determined. Larger studies are needed to better evaluate associations between LA function and clinical outcomes and the role of LA function as a target for novel HFpEF therapies.