Ventricular resynchronization therapy by direct His-bundle pacing using an internal cardioverter defibrillator

Area of Science:

• Cardiology
• Electrophysiology
• Heart Failure Management

Background:

• Cardiac resynchronization therapy (CRT) improves refractory heart failure in patients with QRS width >120 ms.
• Internal cardioverter defibrillators reduce mortality in these patients.
• Conventional CRT involves left ventricular (LV) stimulation via the coronary sinus, which is not always feasible.

Purpose of the Study:

• To evaluate Direct His-bundle pacing (DHBP) as an alternative CRT method.
• To assess DHBP's efficacy in patients unsuitable for coronary sinus pacing.
• To determine if DHBP can correct conduction disturbances and improve LV function.

Main Methods:

• Patients with refractory heart failure were selected for CRT and internal cardioverter defibrillator insertion.
• Included were patients where LV stimulation via coronary sinus was not achievable.
• DHBP was attempted, focusing on achieving left bundle branch block disappearance and successful electrode fixation.

Main Results:

• Direct His-bundle pacing corrected basal conduction disturbances in 81% (13/16) of selected patients.
• Successful definitive resynchronization was achieved in 9 patients.
• These patients showed improved functional class and LV function parameters via echocardiography.

Conclusions:

• Direct His-bundle pacing (DHBP) presents a viable alternative for CRT in specific patient groups.
• DHBP can effectively treat conduction abnormalities when coronary sinus pacing fails.
• This approach holds promise for improving outcomes in selected heart failure patients.