2013Heart failureArrhythmias & devices809 patients

EchoCRT

Therapy group: Cardiac resynchronization therapy · Therapy: CRT in narrow QRS

CRT in heart failure with narrow QRS and echocardiographic dyssynchrony showed no benefit and was stopped for futility, with a possible mortality signal.

Published in N Engl J Med (2013)

Question: Does cardiac resynchronization therapy (CRT) benefit patients with systolic heart failure and a narrow QRS who show echocardiographic left ventricular dyssynchrony?
Design: Randomized trial at 115 centers; all patients underwent device implantation and were assigned to CRT turned on or off. A total of 809 patients were randomized and followed for a mean of 19.4 months. The study was stopped for futility on the recommendation of the data and safety monitoring board.
Population: Patients with NYHA class III or IV heart failure, left ventricular ejection fraction of 35% or less, QRS duration under 130 msec, and echocardiographic evidence of left ventricular dyssynchrony.
Intervention: Device implantation with CRT capability turned on.
Control: Device implantation with CRT capability turned off.
Primary outcome: Composite of death from any cause or first hospitalization for worsening heart failure.
Results: The primary outcome occurred in 116 of 404 patients in the CRT group and 102 of 405 in the control group (28.7% vs. 25.2%; HR 1.20; 95% CI 0.92 to 1.57; P=0.15). There were 45 deaths in the CRT group and 26 in the control group (11.1% vs. 6.4%; HR 1.81; 95% CI 1.11 to 2.93; P=0.02).
Conclusion: In patients with systolic heart failure and QRS duration under 130 msec, CRT did not reduce death or heart failure hospitalization and may increase mortality.
Why it matters: The trial showed that echocardiographic dyssynchrony alone does not justify CRT when the QRS is narrow, and it discouraged use of this therapy in that setting.

Card generated automatically with AI from the abstract of the original publication and the trial registry; every figure was checked against those sources. It may contain errors: verify the data at the source before using it for clinical decisions.

Generated on October 14, 2026

Sources

Original publication on PubMed (PMID 23998714) ↗Cardiac-resynchronization therapy in heart failure with a narrow QRS complex.
Journal article (DOI) ↗
ClinicalTrials.gov record (NCT00683696) ↗

Videos explaining it

EHJ Today - An EchoCRT Substudy

ESC · European Society of Cardiology ↗10:57Video page

Source: European Society of Cardiology · YouTube
Date: 8 Sept 2015
Audio: English
Subtitles: MultilingualYouTube
Audio transl.: None

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