Poor R-wave progression linked to sudden cardiac death: Study

Finland: Poor R-wave progression (PRWP) may be associated with adverse prognosis in the general population and with sudden cardiac death (SCD) in patients with coronary artery disease (CAD), suggests an article published in Heart Rhythm.The study data in the article indicates that diagnostic measures regarding underlying CAD in subjects with PRWP are necessary.

An observational study of 6854 patients (30 years or older) from a Finnish general population was conducted by Linda C., University of Helsinki, Finland and colleagues to examine the risk of SCD and overall prognosis associated with PRWP in general population subjects with and without CAD.

Recently it was reported that about 10% of the deaths in India are due to sudden cardiac arrest which is also the leading cause of mortality worldwide. Coronary artery disease (CAD) is the most common underlying condition leading to SCD. Most SCD victims do not present with any indication before the fatal event. Therefore, improvements in SCD risk stratification methods are needed. In a previous study in the general adult population, PRWP was common on the standard 12-lead electrocardiogram (ECG) with a prevalence of 5.1% and was associated with increased total and cardiovascular mortality in women but the risk of SCD associated with PRWP on the resting ECG has not been studied and its prognostic significance is unclear.

For the study, researchers collected the data and 12-lead ECGs from a Finnish general population health examination survey conducted from 1978 to 1980 with follow-up until 2011. The main endpoints were SCD, cardiac death, and all-cause mortality. PRWP was defined as R-wave amplitude ≤ 0.3 mV in lead V3 and R-wave amplitude in lead V2 ≤ R-wave amplitude in lead V3.

Key findings from the data are,

• 213 subjects (3.1%) showed PRWP.

• PRWP was associated with SCD (HR, 2.13), cardiac death (HR, 1.75), and all-cause mortality (HR, 1.29).

• In the subgroup analysis of patients with coronary artery disease (CAD), PRWP had a stronger association with cardiac mortality, whereas no association with SCD was observed in those without CAD.

Researchers conclude that PRWP in an ECG is associated with increased mortality and a markedly elevated risk of adverse cardiac events in the general adult population after adjusting for several cardiac risk factors. The risk of SCD was observed in subjects with CAD. Further studies are needed to establish whether PRWP,  in combination with other risk markers, is useful in SCD risk stratification in specific patient populations the authors suggested.

Linda C. Schröder, Arttu Holkeri, Antti Eranti, M. Anette E. Haukilahti et al. Poor R-wave progression as a predictor of sudden cardiac death in the general population and subjects with coronary artery disease,  Heart Rhythm,2022,     https://doi.org/10.1016/j.hrthm.2022.02.010.