Early left ventricular systolic function is a more sensitive predictor of adverse events after heart transplant

Background First-phase ejection fraction (EF1) is a novel measure of early systolic function. This study was to investigate the prognostic value of EF1 in heart transplant recipients. Methods Heart transplant recipients were prospectively recruited at the Union Hospital, Wuhan, China between January 2015 and December 2019. All patients underwent clinical examination, biochemistry measures [brain natriuretic peptide (BNP) and creatinine] and transthoracic echocardiography. The primary endpoint was a combined event of all-cause mortality and graft rejection. Results In 277 patients (aged 48.6±12.5 years) followed for a median of 38.7 (interquartile range: 18.3) months, there were 35 (12.6%) patients had adverse events including 20 deaths and 15 rejections. EF1 was negatively associated with BNP (β=-0.220, p<0.001) and was significantly lower in patients with events compared to those without. EF1 had the largest area under the curve in ROC analysis compared to other measures. An optimal cut-off value of 25.8% for EF1 had a sensitivity of 96.3% and a specificity of 97.1% for prediction of events. EF1 was the most powerful predictor of events with hazard ratio per 1% change in EF1: 0.628 (95%CI: 0.555-0.710, p<0.001) after adjustment for left ventricular ejection fraction and global longitudinal strain. Conclusions Early left ventricular systolic function as measured by EF1 is a powerful predictor of adverse outcomes after heart transplant. EF1 may be useful in risk stratification and management of heart transplant recipients.