Heart rate changes after phlebotomy in polycythaemia vera and healthy donors: An observational case‐crossover pilot study

This pilot study demonstrates that any acute haemoglobin reduction, even within the normal range, induces measurable heart rate changes that are directly related to probably the most optimal oxygen delivery state. Moreover, our studies show that wearable technology is sensitive enough to detect these effects. Hence, this nowadays readily available telemetry allows monitoring of subtle physiological changes in a research setting, but it also offers a path towards optimising QoL for patients with anaemia, polyglobulia and for blood donors.