This study sought to study the effect of echocardiographic response to cardiac resynchronization therapy (CRT) on ventricular arrhythmias (VA). The effect of CRT-defibrillator on sustained VA was compared with implantable cardioverter-defibrillator (ICD)-only therapy.
CRT is an effective adjunctive therapy in selected patients with advanced congestive heart failure, but its effect on VA remains controversial.
PubMed was searched to identify studies. For primary comparison, studies reporting incidence of VA in patients with congestive heart failure with CRT compared with ICD were included. For secondary comparison, studies reporting incidence of VA in echocardiographic responders compared with nonresponders were included. Studies reporting incidence of VA in CRT nonresponders before and after CRT upgrade from ICD were assessed for the third comparison. Inverse variance method in a random-effects model was used to combine effect sizes.
Thirteen studies (4,631 subjects) were included in the primary meta-analysis. Patients with CRT had a significantly lower incidence of VA compared with patients with ICD only (odds ratio: 0.754; confidence interval: 0.594 to 0.959). Thirteen studies (n = 3,667) were included in the meta-analysis of VA in CRT responders versus nonresponders. Responders had a significantly lower risk of VA (odds ratio: 0.436; confidence interval: 0.323 to 0.589). Multivariate meta-regression showed that the percentage beta-blocker use and follow-up duration explained heterogeneity between the studies. Three studies were included in the comparison of VA in CRT nonresponders before and after upgrade from ICD. CRT nonresponders had an elevated risk of VA compared with ICD-only subjects (odds ratio: 1.497; confidence interval: 1.225 to 1.829).
CRT may significantly reduce risk of VA compared with ICDs in patients who meet criteria for CRT. CRT responders have significant reduction in VA compared with nonresponders. CRT nonresponse might significantly increase risk of VA.
This research output has an Altmetric Attention Score of 5. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 30 June 2016.
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#8,075,345
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Outputs from JACC: Clinical Electrophysiology
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#107,371
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Outputs of similar age from JACC: Clinical Electrophysiology
#22
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Altmetric has tracked 27,406,235 research outputs across all sources so far. This one has received more attention than most of these and is in the 70th percentile.
So far Altmetric has tracked 1,756 research outputs from this source. They typically receive a lot more attention than average, with a mean Attention Score of 20.8. This one is in the 29th percentile – i.e., 29% of its peers scored the same or lower than it.
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We're also able to compare this research output to 36 others from the same source and published within six weeks on either side of this one. This one is in the 38th percentile – i.e., 38% of its contemporaries scored the same or lower than it.
