Rate-Adaptive Atrial Pacing for Heart Failure With Preserved Ejection Fraction

To the Editor The recent RAPID-HF study explored the important concept of supporting heart rate in patients with heart failure and chronotropic insufficiency. Although the study reached a null conclusion, I believe it is important not to overextrapolate the findings. Cardiac output, by definition, is heart rate  × stroke volume. Because these are not independent variables, the authors saw that when exercise heart rate was increased with atrial pacing, they could not measure an increase in cardiac output.
Source: JAMA - Category: General Medicine Source Type: research