Electrocardiographic pattern in V1, aVL and I as predictor of events in heart failure following cardiac resincronization

Funding Acknowledgements

Type of funding sources: None.

Introduction

following cardiac resincronization therapy (CRT), QRS duration is the most important prognostic factor in the 12-lead electrocardiogram (ECG). However, there is little evidence regarding if the electrocardiographic pattern following CRT has impact on morbidity and mortality.

Purpose

In this historical cohort study we analysed if a certain pattern in three leads of the ECG (Rs in V1, Qr in aVL or rS in I) is associated with lower incidence of adverse outcomes in a population of CRT patients within 1 year of implant. Other variables previously associated with success or failure of CRT were analysed.

Methods

patients with CRT devices with left ventricle lead in the coronary sinus were included from January 2012 to April 2019. The primary endpoint was a composite of death of any cause and heart failure hospitalization at 1 year. Survival analysis was performed using Kaplan-Meier test, comparing survival graphics through Log-Rank test. For multivariate analysis, Cox regression was performed.

Results

111 patients were included. Sample was divided into 2 groups according to the presence of the pattern in any of the three ECG leads. Baseline characteristics are reported in Table 1. Presence of any of the three patterns was independently associated with a lower incidence of the primary endpoint (2.3% vs. 17.6%, hazard ratio 0.1, 95% confidence interval 0.013-0.774, p = 0.016). Previous atrial fibrillation was also independently associated with a higher incidence of the primary endpoint. QRS duration postimplantation did not showed prognostic value.

Conclusion

the presence of the patterns Rs in V1, Qr in aVL or rS in I is an independent predictor of good prognosis in patients with CRT. Baseline characteristicsPattern Rs-V1/Qr-aVL/rS-INo patternp-valueAge (years)69 ± 1767 ± 210.257Women8 (18.6)17 (25)0.432Atrial fibrillation18 (41.9)22 (32.4)0.309- Ischemic cardiomyopathy- Non ischemic cardiomyopathy18 (41.9)25 (58.1)26 (38.8)41 (61.2)0.75Indication- HFrEF + NYHA II-IV + wide QRS- rEF + indication of cardiac stimulation- LV dysfunction secondary to stimulation 35 (81.4)7 (16.3)1 (2.3) 58 (85.3)9 (13.2)1 (1.5) 0.5870.6560.741Preimplantation LVEF (%)28 ± 1328 ± 150.882Up-titrated treatment17 (39.5)26 (38.2)0.891- LBBB- RBBB36 (83.7)5 (11.6)61 (89.7)6 (8.8)0.3550.63QRS duration postimplantation (ms)144 ± 35142 ± 500.657HFrEFheart failure with reduced ejection fraction; NYHA: New York Heart Association; rEF: reduced ejection fraction; LV: left ventricle; LVEF: left ventricle ejection fraction; LBBB: left bundle branch block; RBBB: right bundle branch block.Abstract Figure. Kaplan Meier survival curves

Polymorphisms in the GNAS Gene as Predictors of Ventricular Tachyarrhythmias and Sudden Cardiac Death: Results From the DISCOVERY Trial and Oregon Sudden Unexpected Death Study

Background

Population‐based studies suggest that genetic factors contribute to sudden cardiac death (SCD).

Methods and Results

In the first part of the present study (Diagnostic Data Influence on Disease Management and Relation of Genetic Polymorphisms to Ventricular Tachy‐arrhythmia in ICD Patients [DISCOVERY] trial) Cox regression was done to determine if 7 single‐nucleotide polymorphisms (SNPs) in 3 genes coding G‐protein subunits (GNB3, GNAQ, GNAS) were associated with ventricular tachyarrhythmia (VT) in 1145 patients receiving an implantable cardioverter‐defibrillator (ICD). In the second part of the study, SNPs significantly associated with VT were further investigated in 1335 subjects from the Oregon SUDS, a community‐based study analyzing causes of SCD. In the DISCOVERY trial, genotypes of 2 SNPs in the GNAS gene were nominally significant in the prospective screening and significantly associated with VT when viewed as recessive traits in post hoc analyses (TT vs CC/CT in c.393C>T: HR 1.42 [CI 1.11‐1.80], P=0.005; TT vs CC/CT in c.2273C>T: HR 1.57 [CI 1.18‐2.09], P=0.002). TT genotype in either SNP was associated with a HR of 1.58 (CI 1.26‐1.99) (P=0.0001). In the Oregon SUDS cohort significant evidence for association with SCD was observed for GNAS c.393C>T under the additive (P=0.039, OR=1.21 [CI 1.05‐1.45]) and recessive (P=0.01, OR=1.52 [CI 1.10‐2.13]) genetic models.

Conclusions

GNAS harbors 2 SNPs that were associated with an increased risk for VT in ICD patients, of which 1 was successfully replicated in a community‐based population of SCD cases. To the best of our knowledge, this is the first example of a gene variant identified by ICD VT monitoring as a surrogate parameter for SCD and also confirmed in the general population.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00478933.

Radiation protection in digestive endoscopy: European Society of Digestive Endoscopy (ESGE) guideline

This article expresses the current view of the European Society of Gastrointestinal Endoscopy (ESGE) about radiation protection for endoscopic procedures, in particular endoscopic retrograde cholangiopancreatography (ERCP). Particular cases, including pregnant women and pediatric patients, are also discussed. This Guideline was developed by a group of endoscopists and medical physicists to ensure that all aspects of radiation protection are adequately dealt with. A two-page executive summary of evidence statements and recommendations is provided. The target readership for this Guideline mostly includes endoscopists, anesthesiologists, and endoscopy assistants who may be exposed to X-rays during endoscopic procedures.