Left Ventricular Assist Device-Mediated Cardiac Recovery: Impact of Diabetes Mellitus and Glycemic Control

Abstract

<h3>Purpose</h3> Type 2 diabetes mellitus (DM) and poor glycemic control portend a higher risk for cardiovascular morbidity and mortality. We sought to assess their impact on left ventricular assist device (LVAD)-mediated cardiac recovery in chronic advanced heart failure (HF). <h3>Methods</h3> Consecutive patients (N=477) receiving a durable continuous-flow LVAD were prospectively evaluated. After excluding patients with acute HF etiologies or inadequate follow-up after LVAD (<3 months), 396 patients were stratified based on pre-LVAD DM status into non-diabetics (n=121; no history of DM and HbA1c <5.7) and diabetics/prediabetics (n=275; history of DM or HbA1c ≥5.7). Diabetics/prediabetics were further divided into 3 groups: prediabetics, n=106; well-controlled DM (HbA1c <7%), n=90; or not well-controlled DM, n=79. The absolute left ventricular ejection fraction (LVEF) change (ΔLVEF = LVEF post-LVAD - LVEF pre-LVAD) within one year on LVAD support was compared between groups with linear regression. DM is frequently associated with ischemic cardiomyopathy (ICM), so patients were stratified a priori into ICM and non-ICM (NICM). <h3>Results</h3> Compared to non-diabetics, diabetics/prediabetics were older, more likely male, with a higher BMI, and more commonly had an ICM, remote history of hypertension, and a longer HF symptoms duration. The <b>Figure</b> depicts the ΔLVEF between the study groups stratified into ICM or NICM. After adjusting for age, sex, BMI, HF symptoms duration, and history of hypertension, patients with well-controlled DM responded more favorably compared to patients with poor glycemic control. Overall, NICM patients responded more favorably than ICM patients. <h3>Conclusion</h3> DM appears to negatively affect functional cardiac improvement on LVAD support and effective glycemic control seems to be beneficial in enhancing the favorable myocardial functional response. Further research is warranted to investigate the underlying mechanisms driving the differential responses.