Post systolic shortening by speckle tracking echocardiography as a predictor for cardiovascular events in patients with type 2 diabetes

Background: Post systolic shortening (PSS), measured by speckle tracking echocardiography has emerged as a novel method to evaluate left ventricular function and has been linked to adverse outcomes. Purpose: Our aim was to assess if the presence of pathological PSS had prognostic value in the prediction of major cardiovascular events in a cohort of patients with type-II diabetes (T2D). Method: Three-hundred-and-sixty-four patients with T2D in the CARDIPP study (Cardiovascular Risk factors in Patients with Diabetes – a Prospective study in Primary care) underwent echocardiography between 2005 and 2009. All patients were evaluated with strain analysis by speckle tracking. PSS was defined as any myocardial contraction occurring after aortic valve closure (Figure 1). Pathological PSS was defined as a post systolic index (PSI) >5% where PSI was calculated as: (peak global longitudinal strain – peak systolic longitudinal strain) / (peak global longitudinal strain) x 100. The composite endpoint of any major cardiovascular event (MACE) was defined as the diagnosis of or death in heart failure, myocardial infarction, or stroke. Cox proportional hazard ratios (HR) with 95% confidence intervals were calculated and were adjusted for sex, age, body mass index, hypertension, smoking, previous cardiovascular events and HbA1c. Results: Mean follow-up time was 11.2±2.3 years. Patients with pathological PSS had an increased unadjusted risk of MACE, (HR 3.73, 95% CI 2.06–6.76), which persisted after adjustment (HR 2.20, 95% CI 1.11–4.37) as compared to subjects without pathological PSS. When adding PSS to a risk prediction model including Global Longitudinal Strain (GLS), the adjusted HR (95% CI) for MACE was 2.94 (1.33–6.52) for subjects with reduced GLS (lower limit of normal −16%) and PSI >5%, compared to those with normal GLS and PSI ≤5%. Adverse events were more common in subjects with the combination of pathological PSS and GLS (Figure 2). Conclusions: Our results suggest that PSS may provide important additional prognostic information in patients with T2D.