Global left ventricular myocardial work index and medium-term adverse cardiovascular events after ST-elevation myocardial infarction

Abstract

Background: Left ventricular global longitudinal strain (GLS) has incremental prognostic value over ejection fraction (EF) in patients with ST-segment-elevation myocardial infarction (STEMI), but it is also load dependent. It has been recently demonstrated that Myocardial work (MW), integrating blood pressure with GLS, predicts long-term all-cause mortality. We aimed to further explore the prognostic value of MW for cardiovascular endpoints in patients with STEMI.

Methods and results: Retrospective study of 200 consecutive patients admitted with a STEMI, mean age of 62 (SD 12) years, 79.5% males, that survived to discharge. Transthoracic echocardiography was performed before discharge (5 ± 3 days after admission). Mean follow-up was 790 days. The primary outcome was a composite of cardiovascular death, non-fatal myocardial infarction, and unplanned cardiovascular admission (ACE). During follow-up, 26 patients had a ACE. In univariable Cox regression analysis, male gender, body mass index, GRACE risk score and Global Work Index (GWI) were selected to the multivariable analysis, in which, only GWI (per 100 mmHg% decrease: hazard ratio estimate 1.19, 95% confidence interval 1.07-1.34, p-value = 0.002) remained independently associated with ACE, with effective reclassification of non-events. The best GWI cut-off to predict ACE was ≤1165 mmHg% (Log-rank, p = 0.034).

Conclusions: LV GWI is independently associated with medium-term ACE. Nevertheless, prospective studies in a larger sample of patients are warranted to confirm this finding.

Keywords: Myocardial infarction; Myocardial work; Prognosis; Strain.