Increased Resting Heart Rate on Electrocardiogram Relative to In-office Pulse Rate Indicates Cardiac Overload: The J-HOP Study

BACKGROUND: Heart rate (HR) assessed by electrocardiogram (ECG-HR) and pulse rate (PR) measured in a physician's office (office-PR) are taken with subjects in different body positions-i.e., supine vs. sitting. Although analysis of HR differences according to body position could provide new practical insights, there have been few studies on the subject. We herein investigated whether the difference between office-PR and ECG-HR (delta HR) was associated with brain natriuretic peptide (BNP) levels and left ventricular mass (LVM). METHODS: Among the 4,310 patients with 1 or more cardiovascular risk factors recruited for the Japan Morning Surge-Home Blood Pressure study, we excluded those with atrial fibrillation or a prescribed β-blocker. We analyzed the 2,972 patients who had ECG-HR, office-PR, and BNP data and 1,061 patients with echocardiography data. RESULTS: In the complete patient series, office-PR was significantly higher than ECG-HR (72.1 ± 10.3 vs. 66.6 ± 11.9 bpm, P < 0.001). When we divided patients into quintiles based on the delta HR, the BNP level and LVM index (LVMI) decreased across categories after adjustment for traditional cardiovascular risk factors (each P ≤ 0.001). In a multiple linear regression analysis, the delta HR was independently and significantly associated with both the log-transformed BNP level (β = -0.179, P < 0.001) and LVMI (β = -0.113, P = 0.001) adjusted for covariates. CONCLUSION: A decreased delta HR was positively associated with the BNP level and LVMI. Without the requirement of a special technique, this evaluation might indicate potential cardiac overload and provide a clinical sign related to heart failure.