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Cardiopulmonary Exercise Testing-Guided Optimization of Pacemaker Rate-Response in an Endurance Athlete With Sinus
Paishiun Nelson Hsieh1, Katherine Falvey2, Andreas Kontopidis3
1Cardiovascular Performance Program, Division of Cardiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Background:
Athletes with a permanent pacemaker for sinus node dysfunction can experience exercise intolerance related to suboptimal rate-response pacing, often isolated to periods of peak or prolonged effort. Nominal pacemaker rate modulation settings do not recapitulate physiological exercise well.
Case Summary:
We present a case of a 70-year-old lifelong runner with implanted permanent pacemaker for sinus node dysfunction presenting with exercise intolerance and dyspnea on exertion. A combined maximum effort cardiopulmonary exercise test with device interrogation produced an optimized pacemaker settings profile which resolved his symptoms.
Discussion:
Highly active patients with sinus node dysfunction depend on rate-response pacing during exercise. Optimized pacemaker function for high intensity sports can relieve symptoms and improve performance. Our case highlights the importance of an athlete-tailored approach combining maximum effort metabolic, exercise, and device testing.
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