Yes—it's possible, but it depends on the type of heart failure, fitness level, medications, and device support. 7,500 m in 60 min is typically light-to-moderate intensity. A flat ~60 bpm during exercise is unusual unless there’s a pacemaker limit, beta‑blockers, very high fitness, or the effort is truly low. The key is whether heart rate can rise appropriately with intensity and whether any symptoms occur.
With EF ~45% (mildly reduced), no meds, a unicameral leadless pacemaker, and no symptoms, the scenario is physiologically plausible—especially if the patient is well conditioned. The heart-rate behavior is the main signal: if HR stays fixed, it could cap peak cardiac output; if it rises with effort, that’s reassuring. Device programming (rate responsiveness, lower rate limit) and overall functional capacity matter more than EF alone.
This is a coherent picture. A resting HR ~50 suggests good intrinsic rhythm and athletic adaptation, with the Aveir VR likely acting as backup at the programmed lower rate. The ability to increase HR to ~90 with higher effort indicates preserved chronotropic response (either intrinsic or via device sensing), so exercise capacity is less likely to be limited by the pacemaker during moderate rowing. EF 45% does not automatically prevent steady endurance activity when the patient is asymptomatic and conditioned.
Moderate 60‑minute rowing is unlikely to cause pathological myocardial damage in a stable, asymptomatic person with EF ~45% and appropriate HR increase. However, both high‑sensitivity troponin and BNP/NT‑proBNP can rise transiently after exercise—even in healthy people—due to temporary physiologic stress (not necessarily infarction). What matters is pattern: • Mild, short‑lived rises that return to baseline within ~24–48 hours can be physiologic. • Persistent or progressively rising values, new symptoms, declining exercise tolerance, or ischemic features would be concerning and warrant medical evaluation. Trends over time and timing of the blood draw (immediately after exercise vs. at rest) are critical for interpretation.