Background: Recent studies have shown that myocardial constructive work (CW) is an independent predictor of the volumetric response to cardiac resynchronization therapy (CRT).
Purpose of the study: To assess if CW is additive to volumetric CRT-response in the prediction of cardiac mortality in CRT-candidates.
Methods: 2D-standard and speckle-tracking echocardiography were performed in 166 CRT candidates (mean age: 66±10 years, males: 69%) before CRT implantation and at 6-month follow-up. Left ventricular (LV) CW was assessed by pressure-strain loops (PSLs). A reduction in LV end-systolic volume >15% at 6-month follow-up defined CRT-volumetric response and was observed in 48 (29%) patients.
Results: After a median 4-year FU (range: 1.3–5 years), cardiac death occurred in 14 patients (8%). CW and age were the only prognostic predictors of cardiac death (Table 1), independently from septal flash and CRT-volumetric response. At ROC curve analysis, CW≤888 mmHg% was the best cut-off to predict cardiac mortality (AUC 0.71, p=0.007). Among CRT responders, the presence of CW≤888 mmHg was associated with a dismal prognosis (log-rank test p=0.04). The concomitance of CW≤888 mmHg and absence of volumetric response to CRT identified patients with the worst prognosis (log-rank test p=0.001) (Figure 1)
Conclusions: Left ventricular CW allows the prediction of cardiac death in CRT candidates. A CW≤888 mmHg is associated with a increased cardiac mortality in both CRT responders and non-responders.