Undetected Heart Failure in Cardiology: Prevalence, Characteristics, and Outcome.

AIM: To confirm or refute recent pilot studies showing unexpectedly high rates of undetected heart failure (HF) in cardiology patients. METHODS: We assessed the prevalence, characteristics, and outcome of undetected HF in a large prospective cohort study of patients referred for non-invasive coronary artery disease (CAD) work-up with cardiac positron emission tomography computed tomography. HF presence and phenotype were centrally adjudicated by an independent cardiologist according to clinical practice guidelines requiring three mandatory criteria: symptoms, elevated natriuretic peptides, and structural/functional cardiac abnormalities. The endpoint was a composite of cardiovascular death and acute HF (AHF) hospitalization through 2-year of follow-up. RESULTS: Among 1738 eligible patients (median age 67 years, 30% women), 138 patients (7.9%) had known HF, and 534 of 1600 patients (33.4%) without known HF had adjudicated undetected HF, resulting in a ratio of undetected HF to known HF of 3.9 (95%CI, 3.2-4.7)-to-1 and a number needed to screen to detect one patient with undetected HF of 3.0 (95%CI, 2.9-3.1). In undetected HF, left ventricular ejection fraction (LVEF) was preserved in 72.3%, mildly reduced in 16%, and reduced in 11.7%. Older age, known CAD, atrial fibrillation, previous pacemaker implantation, and ECG abnormalities were associated with a higher likelihood for undetected HF. Undetected HF was associated with an increased cumulative incidence of the composite endpoint (adjusted subdistribution hazard ratio 7.37 [95%CI, 3.87-14.06], p<0.001, versus no HF). CONCLUSION: One-out-of three patients referred for CAD work-up had undetected HF, which was associated with cardiovascular death and AHF hospitalization.