A randomized double-blind crossover comparison of four rate-responsive pacing modes

Area of Science:

• Cardiology
• Biomedical Engineering
• Medical Devices

Background:

• Rate-responsive pacemakers adjust heart rate based on physiological demand.
• Modern pacemakers offer various pacing modes with different sensor functionalities.
• Optimizing pacemaker mode selection is crucial for patient quality of life and physiological response.

Purpose of the Study:

• To compare subjective and objective outcomes of four modern rate-responsive pacemaker modes.
• To evaluate patient preference and physiological performance across VVIR, DDIR, DDD, and DDDR pacing modes.
• To determine the superiority of dual-sensor pacing over single-sensor modes.

Main Methods:

• Double-blind crossover study involving 22 patients with DDDR pacemakers.
• Randomized programming to VVIR, DDIR, DDD, or DDDR modes for 4 weeks each.
• Subjective assessments (well-being, symptoms) and objective measures (exercise capacity, cardiac output, regurgitation) were performed.

Main Results:

• DDDR mode was preferred by 59% of patients; VVIR was least acceptable in 73%.
• VVIR pacing showed significantly worse well-being, exercise capacity, and functional status compared to dual-rate-responsive modes.
• DDDR pacing demonstrated longer exercise treadmill times and improved cardiac output at rest.
• Heart rate response to mental stress was suboptimal in VVIR and DDIR modes.
• Tricuspid regurgitation was significantly greater in VVIR mode than in dual modes.

Conclusions:

• Dual-sensor DDDR pacing is objectively and subjectively superior to single-sensor VVIR, DDIR, and DDD pacing.
• DDDR pacing improves patient well-being, exercise capacity, and hemodynamic function.
• Subjective benefits of dual-chamber rate-augmented pacing can be predicted echocardiographically.