Chronotropic Incompetence in Chronic Heart Failure

Abstract

Chronotropic incompetence (CI) is generally defined as the inability to increase the heart rate (HR) adequately during exercise to match cardiac output to metabolic demands. In patients with heart failure (HF), however, this definition is unsuitable because metabolic demands are unmatched to cardiac output in both conditions. Moreover, HR dynamics in patients with HF differ from those in healthy subjects and may be affected by β-blocking medication. Nevertheless, it has been demonstrated that CI in HF is associated with reduced functional capacity and poor survival. During exercise, the normal heart increases both stroke volume and HR, whereas in the failing heart, contractility reserve is lost, thus rendering increases in cardiac output primarily dependent on cardioacceleration. Consequently, insufficient cardioacceleration because of CI may be considered a major limiting factor in the exercise capacity of patients with HF. Despite the profound effects of CI in this specific population, the issue has drawn limited attention during the past years and is often overlooked in clinical practice. This might partly be caused by a lack of standardized approach to diagnose the disease, further complicated by changes in HR dynamics in the HF population, which render reference values derived from a normal population invalid. Cardiac implantable electronic devices (implantable cardioverter defibrillator; cardiac resynchronization therapy) now offer a unique opportunity to study HR dynamics and provide treatment options for CI by rate-adaptive pacing using an incorporated sensor that measures physical activity. This review provides an overview of disease mechanisms, diagnostic strategies, clinical consequences, and state-of-the-art device therapy for CI in HF.

Wearable Monitoring and Interpretable Machine Learning Can Objectively Track Progression in Patients during Cardiac Rehabilitation

“…Moreover, chronotropic response as an extra input feature contributed to the ability to predict functional capacity in the CR population. This is in line with previous studies, which have already shown that chronotropic response is a significant predictor of training response during a CR program [35,36]. If CR is moved to an in-home setting, proper context interpretation is necessary.…”

Heart rate score, a measure related to chronotropic incompetence in pacemaker patients

“…An association between CI and HF was recently reviewed. 19 CI is a heterogeneous phenotypic diagnosis with multiple associated etiologic causes, such as HF and pharmacologic therapy. 8 , 13 As there are multiple methods of assessment and detection of CI, the incidence, prevalence, and even definitions of CI vary widely.…”

Prognostic value of pupil area for all‐cause mortality in patients with heart failure

“…Although the mechanism underlying this association has yet to be determined, we postulated that it may be similar to the mechanism of chronotropic incompetence. Chronotropic incompetence is defined as the inability to adequately increase heart rate during exercise to match cardiac output to metabolic demands and is associated with poor exercise tolerance and high mortality rate 28,29 . Autonomic dysfunction has been reported to be responsible for chronotropic incompetence 30 .…”

“…Chronotropic incompetence is defined as the inability to adequately increase heart rate during exercise to match cardiac output to metabolic demands and is associated with poor exercise tolerance and high mortality rate. 28,29 Autonomic dysfunction has been reported to be responsible for chronotropic incompetence. 30 We measured pupil area after dark adaptation in this study, and the pupils commonly dilate in the dark because of appropriate autonomic nervous activity.…”