Background: Chronotropic incompetence (CI) has been associated with cardiovascular mortality. However, its relationship with long-term risk of heart failure (HF) is not well studied.
Methods: We included 43,098 participants (mean age 51.7±12.3 years, 47.5% females, 66.6% white) of the FIT project who completed a clinically indicated exercise test between 1991 and 2009. Patients with coronary artery disease, prior HF or on heart rate reducing medications were excluded. Incident HF was defined by having a documented diagnosis in 3 separate clinical encounters. CI was defined by inability to achieve 85% of maximal age predicted heart rate (calculated by 220 - age) with exercise. Multivariable adjusted Cox models were used to assess the independent association of CI with incident HF.
Results: At baseline, 5,249 (12.2%) had CI. After a mean follow-up duration of 10.9 ± 4.6 years, 1329 (3.2%) experienced new onset HF. The cumulative incidence of HF was 397 (7.6%) among CI patients compared with 992 (2.6%) among chronotropic competent patients. Figure 1 shows the cumulative incidence of heart failure by CI status. In multivariable Cox regression models, CI was associated with increased risk of incident heart failure (HR 1.73; 95% CI 1.48 – 2.03, p \u3c0.001) after adjusting for confounders. There were no interactions by age, sex, race, body mass index. Conclusions: Our study shows that CI is an independent risk factor for HF. Further research is needed to determine whether CI could be a therapeutic target for HF
