Effect of Cardiac Resynchronization Therapy in Patients With Insulin-Treated Diabetes Mellitus

Area of Science:

• Cardiology
• Diabetology
• Medical Technology

Background:

• Diabetes mellitus (DM) significantly impacts outcomes for patients with heart failure (HF).
• Understanding the specific risks and benefits of advanced therapies in diabetic HF patients is crucial.

Purpose of the Study:

• To analyze mortality, HF events, and ventricular arrhythmias (VT/VF) in HF patients with and without DM.
• To determine if cardiac resynchronization therapy with a defibrillator (CRT-D) improves outcomes in these subgroups, stratified by insulin use.

Main Methods:

• Analysis of 1,278 patients with left bundle branch block from the Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy.
• Cox proportional hazards regression models were used to compare CRT-D versus implantable cardioverter defibrillator outcomes.
• Subgroup analysis included patients without DM, DM without insulin, and DM with insulin treatment.

Main Results:

• CRT-D significantly reduced all-cause mortality by 76% in diabetic patients treated with insulin (interaction p=0.043).
• Significant risk reductions in HF alone, HF/death, and VT/VF were observed across all investigated groups with CRT-D.
• Similar left ventricular reverse remodeling was noted with CRT-D in all subgroups.

Conclusions:

• Diabetic patients with mild HF on insulin treatment derive substantial benefits from CRT-D, including reduced mortality, HF events, and VT/VF.
• Diabetic patients not requiring insulin also benefit from CRT-D, primarily through a reduction in HF events.