Impaired Heart Rate Recovery and Chronotropic Incompetence in Patients With Heart Failure With Preserved Ejection FractionCLINICAL PERSPECTIVE (original) (raw)

2010, Circulation: Heart …

Background-This study assessed the chronotropic response to exercise and heart rate (HR) recovery after exercise in a carefully phenotyped group of patients with heart failure with preserved left ventricular ejection fraction (HfpEF) and a control group of similar age and gender distribution. Methods and Results-We studied 41 patients with HfpEF, 41 healthy controls, and 16 hypertensive controls. None were taking HR-limiting medications. All study participants had clinical examination, 12-lead ECG, pulmonary function test, echocardiogram, and metabolic exercise test with HR monitoring throughout exercise. Chronotropic response was measured by the percentage of the HR reserve used during maximal exercise and the peak exercise HR as a percentage of predicted maximal HR. Patients with HfpEF were generally women (70%), overweight, aged 69Ϯ8 years. Controls were of similar gender (63%) and age (67Ϯ6 years). Patients with HfpEF had significantly reduced peak VO 2 compared with controls (20Ϯ4 mL ⅐ kg Ϫ1 ⅐ min Ϫ1 versus 31Ϯ6 mL ⅐ kg Ϫ1 ⅐ min Ϫ1 , PϽ0.001) and greater minute ventilationcarbon dioxide production relationship (VE/VCO 2 slope) (33Ϯ6 versus 29Ϯ4, PϽ0.001). Chronotropic incompetence was significantly more common in patients with HfpEF compared with matched healthy controls as measured by the percentage of the HR reserve used during maximal exercise (63% versus 2%, Ͻ0.001) and percentage of predicted maximal HR (34% versus 2%, Ͻ0.001). In addition, abnormal HR recovery 1-minute after exercise (defined as the reduction in the HR from peak exercise 1-minute after exercise) was also significantly more common in patients with HfpEF compared with controls (23% versus 2%, Pϭ0.01). Hypertensive controls showed similar chronotropic response to peak exercise and HR recovery after exercise as healthy controls.