Abstract P105: Small Magnitude of the Heart Movement Due to Respiration is Associated With Sudden Cardiac Death
Background: Respiration causes heart movement in the chest and proportional change in the heart’s electrical axis. The ECG can be used to measure respiration-related heart motion. The effect of respiration on the ECG is usually considered an artifact. However, it is unknown whether pattern of heart motion due to respiration holds any prognostic value.
Method: After excluding those with atrial fibrillation, or atrial or ventricular premature contractions at baseline visit, 14613 ARIC cohort participants (mean age 54.0±5.8 y; 6595 [45.1%] men; 10744 [73.5%] white, 1311 [9.0%] with prevalent cardiovascular disease (CVD)) were included. The digital resting ECG was analyzed using custom Matlab software. The absolute magnitude of the displacement of the heart due to respiration was calculated on X (left-right), Y (up-down), and Z (anterior-posterior) axes. Sudden cardiac death (SCD) and non-coronary heart disease (CHD) death served as competing outcomes in our analysis.
Results: In CVD-free participants (as compared to prevalent CVD group) heart moved more on X axis (137±46 vs. 128±47 μV; P<0.0001), and less on Z axis (123±52 vs. 127±60 μV; P=0.05). During a median follow-up of 14 years 278 SCDs (96 in CVD group) and 1619 non-CHD (279 in CVD group) deaths occurred. In competing risk analysis that adjusted for age, gender, race, history of myocardial infarction, CHD, heart failure, systolic blood pressure, anti-hypertensive medications, diabetes, smoking, total cholesterol, high density lipoprotein, level of physical activity, use of beta-blockers, left ventricular hypertrophy on ECG and QRS duration, the absolute magnitude of respiration-related heart movement on X axis (SHR 0.74; 95%CI 0.59-0.93; P=0.009) and Z axis (SHR 1.19; 95%CI 1.01-1.41; P=0.042) associated with SCD (but not with non-CHD death) in CVD group, but not in CVD-free participants.
Conclusion: Greater respiration-caused heart motion on Z axis and smaller - on X axis likely reflects cardiomegaly and is associated with increased risk of SCD in patients with CVD.
Author Disclosures: M.M. Kabir: None. E. Ghafoori: None. J.W. Waks: None. S.K. Agarwal: None. D.E. Arking: None. N. Sotoodehnia: None. D.S. Siscovick: None. W. Post: None. C. Henrikson: None. S.D. Solomon: None. E.Z. Soliman: None. J. Coresh: None. M.E. Josephson: None. L.G. Tereshchenko: None.
- © 2015 by American Heart Association, Inc.