Early repolarization and myocardial scar predict poorest prognosis in patients with coronary artery disease

Early repolarization pattern on ECG predicts worse outcomes in patients hospitalized due to chronic heart failure decompensation

BACKGROUND

To improve the outcomes of patients with chronic heart failure (CHF), it is important to identify reliable prognostic tools. Early repolarization pattern (ER) on 12‑lead electrocardiogram (ECG) is a predictor of worse outcomes, which has been widely researched in the general population but not in the CHF population.

OBJECTIVE

To evaluate the incidence and prognostic value of ER and compare its prognostic significance with other non-invasive diagnostic methods for CHF outcomes and hospital readmissions.

METHODS

The study included 301 patients (166 men and 135 women) hospitalized for CHF decompensation. CHF diagnosis was confirmed according to the current guidelines. The patients underwent standard tests and impedance cardiography (ICG) at enrollment and on the day of discharge.

RESULTS

Thirty-one confirmed ER cases (10.3%) were enrolled. During a median follow-up period of 18 months, 128 cardiac-related deaths were observed (42.5%), with 23 (74.2%) and 105 (38.9%) patients in the ER and non-ER groups, respectively (p < 0.001). The ER group had more readmissions than the non-ER group did at 6-months (2 [1, 2] vs. 1 [1, 2]; p=0.04) and 12-months (3 [2-4] vs. 2 [1-3]; p<0.001). ER on ECG (hazard ratio [HR] 2.59; 95% confidence interval [CI] 1.64-4.07; p<0.001), N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels ≥425.5 pmoL/L (HR 5.1; 95% CI 3.33-7.83; p < 0.001), thoracic fluid content (TFC) ≥36.9 1/kΩ (HR 4.6; 95% CI 2.7-7.85, p < 0.001), and left ventricular ejection fraction (LVEF) ≤40% (HR 4.94; 95% CI 2.83-8.65; p < 0.001) were independently and significantly associated with cardiac death.

CONCLUSIONS

The combination of ER, LVEF ≤40%, NT-proBNP, or TFC provides an incremental prognostic value for cardiac-related death in patients with CHF.

Prognostic Assessment of Early Repolarization/J Wave Electrocardiographic Pattern in Patients With Stable Ischemic Heart Disease

Recent studies suggested that early repolarization (ER)/J wave at the electrocardiogram (ECG) is associated with increased risk of sudden death and ventricular arrhythmias in patients with acute myocardial infarction. In this study, we prospectively assessed whether ER/J wave has any long-term prognostic implications in patients with stable ischemic heart disease (IHD). We enrolled consecutive clinically stable patients with documented IHD, referred to undergo a routine ECG. ER (typical concave ST-segment elevation) and J wave were diagnosed according to prospectively defined criteria. The final population included 617 patients with documented IHD (455 men; age 68.1 ± 11 years). ER/J wave was found in 138 patients (22.4%), 13 of whom (2.1%) showed ER and 133 (21.6%) a J wave. At a follow-up of 8.1±2.9 years, 160 deaths occurred (25.9%), 60 (9.7%) attributed to cardiovascular causes. Total mortality was lower in patients with versus those without ER/J wave (18.8% vs 28.0%; hazard ratio [HR] 0.61, 95% confidence interval [CI] 0.40 to 0.93, p = 0.02). The difference, however, was not significant after adjustment for confounding clinical variables (HR 0.78, 95% CI 0.51 to 1.19, p = 0.25). No significant difference was found in cardiovascular death between patients with (7.2%) and those without (10.4%) ER/J wave (adjusted HR 0.78, 95% CI 0.40 to 1.55, p = 0.48). Similar results were obtained for ER and J wave separately, and for ECG location of ER/J wave (inferior or lateral/precordial) and type of J wave (notched or slurred). The ER/J wave pattern at the ECG is not associated with increased risk of long-term mortality in clinically stable patients with a documented history of IHD.

Early repolarization and the severity of coronary artery disease: A case-control study

BACKGROUND

Early repolarization (ER) is a common finding of the routine electrocardiogram (ECG). The ER usually considered a benign ECG finding, nevertheless a controversy. This study was conducted to investigate the relationship between early repolarization (ER) and the severity of coronary artery disease in patients with a diagnostic coronary angiography.

METHODS

This case-control study included ninety patients (45 patients and 45 control groups) with a diagnostic angiography and was conducted in 2015. After obtaining informed consent, patients with angiography for ER were considered as cases and those for other purposes were as controls. Data were analyzed using SPSS software Version 16. A p-value lesser than 0.05 was significant.

RESULTS

The frequency of ER was higher in men (75.6%), and there was a significant relationship between sex and ER (P=0.003). The mean age of the patients in the ER group was lower than that of non-ER patients, but not statistically significant (P=0.1). Abnormal angiography was more prevalent in patients with ER than non-ER patients (59.6% vs. 40.4%). ER morphology showed a significant correlation to abnormal angiography and also stenosis severity (P=0.035).

CONCLUSION

ER was higher in men than in women. There was a significant correlation between the existence of ER morphology and atherosclerosis severity. Screening programs for ER detection may reduce the risk of arrhythmias and prevent related complications.

Prediction of sudden cardiac death in chronic heart failure patients with reduced ejection fraction by ADMIRE-HF risk score and early repolarization pattern

BACKGROUND

AdreView myocardial imaging for risk evaluation in heart failure (ADMIRE-HF) risk score is a novel risk score to predict serious arrhythmic risk in chronic heart failure patients with reduced ejection fraction (HFrEF). Moreover, early repolarization pattern (ERP) has been shown to be associated with an increased risk of sudden cardiac death (SCD) in HFrEF patients. We sought to investigate the prognostic value of combining ADMIRE-HF risk score and ERP to predict SCD in HFrEF patients.

METHODS

We studied 90 HFrEF outpatients with LVEF< 40% in our prospective cohort study. In cardiac MIBG imaging, the heart-to-mediastinum (H/M) ratio was measured on the delayed planar image. ADMIRE-HF risk score was derived from the sum of the point values of LVEF, H/M ratio, and systolic blood pressure. We also assessed ERP on the standard electrocardiogram.

RESULTS

During a median follow-up of 7.5(4.5-12.0) years, 22 patients had SCD. At multivariate Cox analysis, ADMIRE-HF risk score and ERP were independently associated with SCD. Patients with both intermediate/high ADMIRE-HF score and ERP had a higher SCD risk than those with either and none of them.

CONCLUSION

The combination of ADMIRE-HF risk score and ERP would provide the incremental prognostic information for predicting SCD in HFrEF patients.

Early repolarization pattern associated with coronary artery disease and increased the risk of cardiac death in acute myocardium infarction

Background

Early repolarization pattern (ERP) was associated with sudden cardiac death in recent studies. However, the associations between ERP and coronary artery disease (CAD), and ERP and cardiac death caused by acute myocardial infarction (MI) remains unclear.

Methods

We retrospectively enrolled consecutive 1,545 CAD patients and 908 non‐CAD subjects as control group which were confirmed by coronary angiograph. The CAD patients include stable CAD, acute MI patients, and old MI patients. Multivariate logistic regression was employed to evaluate the relationship between ERP and CAD, and ERP and cardiac death caused by acute MI.

Results

Of the 1,545 CAD subjects, there were 1,029 stable CAD patients, 404 acute MI patients, and 112 old MI patients. The incidence of ERP was much higher among patients with CAD than without CAD subjects (20.1% vs. 6.2%, p < .001) after adjusting for major cardiovascular risk factors. No significant correlation was observed between lead region of ERP on 12‐lead ECG and single abnormal artery. Of the 404 acute MI patients, 342 patients survived and 62 patients died. Incidence of ERP was higher in non‐survivor than survivor patients with acute MI (24.2% vs. 17.5%, p = .006) after adjustment for major cardiovascular risk factors.

Conclusion

The incidence of ERP was higher in CAD patients than subjects without CAD and in non‐survivor patients than survivor patients with acute MI. The lead region of ERP on 12‐lead ECG was not associated with single abnormal coronary artery.

Baseline ST elevation and myocardial scar: Results from the multi-ethnic study of atherosclerosis

BACKGROUND

The mechanism of ST elevation on baseline electrocardiograms (ECG) unknown but it may be associated with abnormal myocardial substrate. This paper evaluates whether clinically unrecognized myocardial scar on cardiac magnetic resonance imaging (CMR) is associated with ST elevation at baseline.

METHODS

The Multi-Ethnic Study of Atherosclerosis (MESA) study is a population-based cohort in the United States. Participants were aged 45 through 84 years and free of clinical cardiovascular disease at enrollment in 2000-2002. Our cohort included 1365 participants who underwent both ECG and contrast enhanced CMR in the 5th examination (2010-2012). Multivariable logistic regression examined the association of ST elevation and CMR defined regional myocardial scar after adjusting for cardiovascular risk factors.

RESULTS

Of 1365 participants (58 ±9 years, 52% men), 105 (8%) had scar on CMR. Of these, the scar in 40 participants followed an ischemic pattern and in the other 65 participants followed a non-ischemic pattern. ST elevation at the 5th examination was present in 435 participants: 40 (0.9%) had ST elevations in inferior and 427 (98%) in lateral leads. 2/40 (5%) and 22/427 (5%) participants with inferior and lateral ST elevations, respectively, had evidence of scar. 15 (1.0%) had myocardial scar noted in the basal anterior region. In the fully adjusted models, ST elevation was associated with scar in basal anterior region (OR 18.2, p = 0.031).

CONCLUSIONS

In a community population, ST elevation at baseline in the inferior or lateral leads was associated with myocardial scar in the basal inferior and anterior segments. The previously described association between ST elevation and increased mortality may be mediated by myocardial scar.

Early repolarization is associated with a significantly increased risk of ventricular arrhythmias and sudden cardiac death in patients with structural heart diseases

BACKGROUND

Early repolarization pattern (ERP) has been proved to increase risk of arrhythmia death in the general population, but its prognostic significance in patients with structural heart disease (SHD) is controversial.

OBJECTIVE

The purpose of this study was to conduct a meta-analysis of studies assessing the association between ERP and risk of ventricular arrhythmias (VTAs) and sudden cardiac death (SCD) in patients with SHD.

METHODS

We performed a literature search using MEDLINE (January 1, 1966, to September 25, 2016) and EMBASE (January 1, 1980, to September 25, 2016) with no restrictions. Studies that reported odds ratio (OR) estimates with 95% confidence intervals (CIs) for the associations of interest were included.

RESULTS

The search yielded 19 observational studies, involving 7268 patients that reported 1127 cases of VTAs or SCD. In the selected studies, the point estimates of the ORs were consistently greater than 1. Compared with those without ERP, patients with ERP experienced a significantly increased risk of developing VTAs or SCD (OR 4.76; 95% CI 3.62-6.26), ventricular fibrillation (OR 7.14; 95% CI 4.31-11.82), and SCD (OR 4.07; 95% CI 1.58-10.51). The results were consistent and statistically significant in all subgroups. ERP with J-point elevation in inferior leads, notching configuration, and horizontal or descending ST segment connote higher risk.

CONCLUSION

ERP is associated with a significant increased risk of VTAs or SCD in patients with SHD. Future research should attempt to understand the exact mechanisms for the arrhythmia risk and to introduce ERP in the risk stratification in this patient group.