Wahlberg K, et al. - Through a prospective study of 20 stable outpatients with diastolic dysfunction and pacemakers, the researchers assessed the impacts of a 4-week increase in the lower pacemaker rate to 80 beats per minute (bpm) followed by a reversal to the previous lower heart rates (HR) setting from weeks 4 to 6. Quality of life, six-minute walk test (6MWT) and NT-proBNP levels were evaluated. Pacing at 80bpm markedly enhanced quality of life and the 6MWT. A powerful positive association between the pacing-induced changes in NT-proBNP and baseline QRS intervals was ascertained. Pacing at 80bpm led to a -21±26% decrease in NT-proBNP in subjects with QRS ≤150ms, whereas QRS >150ms had a correlation with a 26±35% increase in NT-proBNP, as exhibited by stratification by QRS. In comparison to 4±26% and 13±26% variation with pacing from the right atrial appendage and right ventricular apical septum, subjects who were physiologically paced from the conduction system had a -46±26% decline in NT-proBNP at 80bpm. Hence, in subjects with diastolic dysfunction, raising the lower rate setting of pacemakers to 80bpm enhanced quality of life, functional capacity and NT-proBNP for those patients with a baseline QRS ≤150ms. Moreover, to patients with left ventricular diastolic dysfunction and heart failure with preserved ejection fraction, higher HRs may offer significant advantages.