Abstract 14767: Delayed R-Wave Peak Time on the 12-lead ECG is Associated With Increased Risk of Sudden Death
Background: Left ventricular hypertrophy (LVH) is associated with sudden cardiac death (SCD), and there is emerging evidence for unique electrical vs. ventricular myocardial mass related mechanisms. We investigated the correlation between delayed R-Wave Peak Time (DRWPT), or intrinsicoid deflection, in the lateral precordial leads and LV mass in patients who suffered SCD.
Methods: In an ongoing prospective, population based study of SCD in a Northwestern US metro region (approx. 1 million population), SCD cases were compared to geographic controls with coronary artery disease (CAD) and no SCD. Archived ECGs (closest and unrelated to SCD event for cases) were evaluated for the presence of DRWPT defined as an intrinsicoid deflection of ≥ 0.05 seconds in V5 or V6. LV mass from echocardiograms and detailed clinical information was obtained for all subjects. Patients with wide QRS (>100 ms) were excluded.
Results: Cases (n=146, Age: 67.7 ± 14.6 yrs, Male: 55.5%) as compared to controls (n=227, Age: 66.3 ± 11.5 yrs, Male: 59.0%) were significantly more likely to have DRWPT on ECG (17.1% vs 9.2%, p=0.02). DRPWT correlated poorly with echo determined LVH (Kappa statistic 0.03) with no significant difference in mean adjusted LV Mass between those with DRWPT versus those without (104.3 ± 34.9 vs. 100.9 ± 33.5 g/m2, p =0.55). Multivariable analysis adjusting for diabetes, renal failure, LV dysfunction and angiotensin receptor blocker use demonstrated a significant association of DRWPT with SCD risk (OR: 2.2, 95% CI: 1.1-4.3, p=0.020). With the addition of echo LVH to the model, this risk was not significantly attenuated (OR: 2.6, 95% CI: 1.3-5.4, p=0.008).
Conclusion: DRWPT was independently associated with SCD risk, and not correlated with increased LV mass. These findings suggest that abnormalities of myocardial conduction velocity should be explored as mechanisms of electrical risk in LVH and SCD.
Author Disclosures: N. Darouian: None. K. Narayanan: None. A. Uy-Evanado: None. C. Teodorescu: None. K. Reinier: None. H. Chugh: None. K. Gunson: None. J. Jui: None. S.S. Chugh: Employment; Significant; NIH. Research Grant; Significant; NIH. Other; Significant; Boston Scientific, Medtronic.
- © 2015 by American Heart Association, Inc.