Prognostic correlates of strain stress echocardiography

Background The assessment of global longitudinal strain (GLS) allows an objective, operator-independent assessment of longitudinal function and left ventricular (LV) contractile reserve during stress echocardiography (SE). OBJECTIVES This study aimed to assess the prognostic correlates of rest and SE-GLS in chronic coronary syndromes (CCS). Methods This prospective, observational, multicenter study enrolled 2,987 patients (1,763 [60%] male; age 64 ± 12 years; ejection fraction 59 ± 8%) with CCS. All patients underwent rest and SE (exercise, n = 1,803; vasodilator, n = 700; dobutamine, n = 484) in 36 accredited laboratories in 15 countries. GLS (absolute values, %) was calculated at rest and peak stress. All patients had, by design, technically successful rest and SE-GLS and follow-up information, and All-cause death and spontaneous (not procedure-related) acute myocardial infarction were the outcome measures. Results Based on SE-GLS response, 2 groups were identified: ΔGLS increase ≥ 2 points (Group 1) or ΔGLS < 2 (Group 2). Patients of Group 2 showed greater prevalence of hypertension and diabetes and lower ejection fraction (see Table), with greater prevalence of inducible ischemia (6.6 vs 3.1%; p<0.001). During a mean follow-up of 13.3 months, (IQ range 8.5-24.2 months), 60 deaths and 59 AMIs occurred (3.6%). Annual event rate was 3.43% in Group 1 and 5.84% in Group 2 (p=0.003). Regarding all-cause mortality, a SE-GLS < 2 response was associated with higher mortality (HR 1.96 [1.08–3.57]; p=0.027) (see Figure 1, upper panel). This effect remained robust after multivariable adjustment for stress modality, peak HR, and clinical covariates (HR 2.03 [1.09–3.81]; p=0.027) and further adjustment for ischemia (HR 1.91 [1.01–3.60]; p=0.045). In the non-ischemic subgroup, SE-GLS < 2 retained its prognostic value (HR 2.35 [1.17–4.72]; p=0.016). For hard events, SE-GLS < 2 was associated with a higher risk (HR 1.94 [1.32–2.83]; p=0.001), persisting after full adjustment (HR 2.01 [1.35-2.99]; p=0.001) (see Figure 1, lower panel). In comparative analyses, LVEF reserve (< 5 points) and elastance failed to maintain significant prognostic value after adjustment. Conclusions A lower increase in GLS-SE is associated with a worse prognosis and may provide objective, operator-independent supportive evidence for SE in CCSClinical and rest echocardiographic findingsKaplan-Meier Hard Events by GLS Change