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Enhancement of bicycle exercise capacity in patients with chronotropic incompetence through closed-loop stimulation:
Su-Kiat Chua1,2, Wen-Ling Chen1,3, Lung-Ching Chen2
1School of Medicine, College of Medicine, Fu Jen Catholic University, 510 Zhongzheng Road, Xinzhuang District, New Taipei City 24205, Taiwan.
Insights
Closed-loop stimulation (CLS) pacing significantly improved exercise capacity and quality of life in patients with chronotropic incompetence (CI). This advanced pacing strategy offers a superior alternative to traditional DDD mode for managing CI patients.
Area of Science:
- Cardiology
- Electrophysiology
- Exercise Physiology
Background:
- Chronotropic incompetence (CI) limits exercise capacity in pacemaker patients.
- Traditional DDD pacing may not adequately address CI during exertion.
- Optimizing pacemaker function is crucial for improving patient outcomes.
Purpose of the Study:
- To compare the effectiveness of closed-loop stimulation (CLS) pacing versus traditional DDD mode in patients with CI.
- To evaluate the impact of DDD-CLS pacing on exercise capacity and quality of life.
Main Methods:
- A single-centre, randomized crossover trial involving 40 patients with CI.
- Patients underwent 2-month periods of DDD-CLS and DDD pacing, with crossover.
- Bicycle-based cardiopulmonary exercise testing (CPET) assessed exercise capacity and other outcomes.
Main Results:
- DDD-CLS pacing significantly improved peak oxygen uptake and oxygen uptake at the ventilatory threshold compared to DDD mode.
- No significant differences were observed in other CPET parameters between the pacing modes.
- Patients reported improved quality of life and a strong preference for DDD-CLS pacing.
Conclusions:
- DDD-CLS pacing enhances exercise capacity and quality of life in patients with CI.
- This pacing mode shows promise as an effective strategy for managing CI.
- Further research may explore long-term benefits and broader applications of DDD-CLS pacing.
Aims:
This study aimed to investigate the effectiveness of closed-loop stimulation (CLS) pacing compared with the traditional DDD mode in patients with chronotropic incompetence (CI) using bicycle-based cardiopulmonary exercise testing (CPET).
Methods And Results:
This single-centre, randomized crossover trial involved 40 patients with CI. Patients were randomized to receive either DDD-CLS or DDD mode pacing for 2 months, followed by a crossover to the alternative mode for an additional 2 months. Bicycling-based CPET was conducted at the 3- and 5-month follow-up visits to assess exercise capacity. Other cardiopulmonary exercise outcome measures and health-related quality of life (QoL) were also assessed. DDD-CLS mode pacing significantly improved exercise capacity, resulting in a peak oxygen uptake (14.8 ± 4.0 vs. 12.0 ± 3.6 mL/kg/min, P < 0.001) and oxygen uptake at the ventilatory threshold (10.0 ± 2.2 vs. 8.7 ± 1.8 mL/kg/min, P < 0.001) higher than those of the DDD mode. However, there were no significant differences in other cardiopulmonary exercise outcome measures such as ventilatory efficiency of carbon dioxide production slope, oxygen uptake efficiency slope, and end-tidal carbon dioxide between the two modes. Patients in the DDD-CLS group reported a better QoL, and 97.5% expressed a preference for the DDD-CLS mode.
Conclusion:
DDD-CLS mode pacing demonstrated improved exercise capacity and QoL in patients with CI, highlighting its potential as an effective pacing strategy for this patient population.
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