Prognostic value of left ventricular apical four-chamber longitudinal strain after heart valve surgery in real-world practice

Abstract

Background Left ventricular longitudinal strain is an emerging marker of ventricular systolic function. However, the prognostic value of apical four-chamber longitudinal strain after heart valve surgery in real-world clinical practice is uncertain. The authors investigated whether left ventricular apical four-chamber longitudinal strain measured in real-world practice is helpful for predicting postoperative outcomes in patients undergoing heart valve surgery. Methods This observational cohort study was conducted in patients who underwent heart valve surgery between January 2014 and December 2018 at a tertiary hospital in South Korea. The exposure of interest was preoperative left ventricular apical four-chamber longitudinal strain. The primary outcome was postoperative all-cause mortality. Results Among 1,773 study patients (median age, 63 years; female, 45.9%), 132 (7.4%) died during a median follow-up of 27.2 months. Preoperative left ventricular apical four-chamber longitudinal strain was significantly associated with all-cause mortality (adjusted hazard ratio, 0.94 per 1% increment in absolute value; 95% CI [0.90, 0.99], P = 0.022), whereas left ventricular ejection fraction (LVEF) was not significantly associated with all-cause mortality (adjusted hazard ratio: 1.01, 95% CI [0.99, 1.03], P = 0.222). Moreover, combining left ventricular apical four-chamber longitudinal strain to the LVEF and conventional prognostic factors enhance the prognostic model for all-cause mortality (P = 0.022). Conclusions In patients undergoing heart valve surgery without coronary artery disease, left ventricular apical four-chamber longitudinal strain measured in real-world clinical practice was independently associated with postoperative survival. Left ventricular longitudinal strain measurement may be helpful for outcome prediction after valve surgery.

Keywords

• cardiac surgery
• echocardiography
• heart valve diseases
• morbidity
• mortality
• strain