Prognostic implications of multiple chamber longitudinal strains and myocardial work in restrictive cardiomyopathy

The prognosis for restrictive cardiomyopathy (RCM) is typically poor, which primarily influenced by the restrictive physiology. This study aimed to evaluate the prognostic significance of longitudinal strains and myocardial work (MW) indices in RCM patients and to create and validate a multivariable model for predicting major adverse cardiac events (MACEs). We enrolled 191 patients with RCM, divided into a training cohort of 128 and a validation cohort of 63, along with 132 healthy controls. Echocardiography was used to assess right ventricular free wall strain (RV-FWS), left ventricular global longitudinal strain (LV-GLS), left atrial peak strain (LAPS), right atrial peak strain (RAPS), and MW indices. Univariate and multivariate stepwise Cox regressions were applied to identify independent prognostic factors and develop a nomogram. With a median follow-up of 977 days, 111 patients experienced MACEs and 76 died. In patients with preserved left ventricular ejection fraction (LVEF), LV-GLS and MW indices were impaired. Longitudinal strains and MW indices were significantly associated with prognosis. We constructed a predictive nomogram including LAPS, RV-FWS, global myocardial work efficiency (GWE), and established clinical predictors, which demonstrated excellent discriminative and calibration properties. Thorough evaluation of longitudinal strains and MW indices is essential, particularly focusing on LAPS, RV-FWS, and GWE.