Effect of cardiac resynchronization therapy in patients with diabetes randomized in EchoCRT

Area of Science:

• Cardiology
• Medical Devices
• Diabetes Management

Background:

• Patients with heart failure (HF) and diabetes have a poorer prognosis.
• Cardiac resynchronization therapy (CRT) is a treatment for HF, but its effectiveness can vary.
• Understanding how diabetes influences CRT outcomes is crucial for personalized treatment.

Purpose of the Study:

• To compare the outcomes of heart failure patients with and without diabetes who were randomized in the Echocardiography Guided Cardiac Resynchronization Therapy (EchoCRT) study.
• To investigate the interaction between diabetes and CRT efficacy in heart failure patients.

Main Methods:

• A post-hoc subgroup analysis of the EchoCRT study.
• Patients with QRS duration <130 ms and left ventricular dyssynchrony were randomized to CRT ON vs. CRT OFF.
• Outcomes, including the primary endpoint (all-cause death or HF hospitalization), were compared between diabetic and non-diabetic subgroups.

Main Results:

• The primary outcome occurred more frequently in patients with diabetes (32.6%) than without (23%, P=0.003).
• A significant interaction was observed: CRT ON vs. CRT OFF showed a higher risk in patients without diabetes (HR 1.58) but not in those with diabetes (HR 0.86; P interaction=0.041).
• This effect was primarily driven by HF hospitalizations, with a pronounced benefit of CRT in diabetic patients with non-ischaemic cardiomyopathy (HR 0.27 vs. 1.79; P interaction=0.005).

Conclusions:

• In the EchoCRT study, heart failure patients with diabetes and narrow QRS complexes showed a signal for less harm from CRT compared to non-diabetic patients.
• This apparent benefit was mainly driven by differences in heart failure hospitalizations.
• The findings suggest a potential differential effect of CRT based on diabetes status, particularly in specific subgroups like non-ischaemic cardiomyopathy.