Evidence map›Paper›PMID 40654199›Full record

ArticleJournal of cardiovascular electrophysiology2025

Utility of Cardiopulmonary Exercise Testing in Assessing Beta-Blocker Efficacy in LQTS: Moving Away From One-Size-Fits-All.

Iqbal El Assaad, Alison K Heilbronner, Kenneth Zahka, Benjamin Hammond, Akash Patel, Peter F Aziz

Abstract readComparative Study
In one paragraph

Article in Journal of cardiovascular electrophysiology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Article
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors.

Iqbal El AssaadChildren's Institute Department of Heart, Vascular & Thoracic, Division of Cardiology & Cardiovascular Medicine, Cleveland Clinic Children's, Cleveland, Ohio, USA.ORCID 0009-0005-5586-1945
Alison K HeilbronnerCleveland Clinic Lerner College of Medicine, Cleveland, Ohio, USA.ORCID 0000-0001-8028-0062
Kenneth ZahkaChildren's Institute Department of Heart, Vascular & Thoracic, Division of Cardiology & Cardiovascular Medicine, Cleveland Clinic Children's, Cleveland, Ohio, USA.
Benjamin HammondDepartment of Pediatric Cardiology, Primary Children's Hospital, Salt Lake, Utah, USA.
Akash PatelChildren's Institute Department of Heart, Vascular & Thoracic, Division of Cardiology & Cardiovascular Medicine, Cleveland Clinic Children's, Cleveland, Ohio, USA.
Peter F AzizChildren's Institute Department of Heart, Vascular & Thoracic, Division of Cardiology & Cardiovascular Medicine, Cleveland Clinic Children's, Cleveland, Ohio, USA.

Funding

The authors received no specific funding for this work.
6 · The paper itself

Abstract

backgroundCurrently, there is no specific standard to assess beta blocker efficacy in long QT syndrome (LQTS).

objectiveTo describe our institutional experience with utilizing cardiopulmonary exercise testing (CPET) to assess for chronotropic suppression and to compare frequency of life-threatening events (LTEs) on intentional "submaximal" treatment to those on maximal treatment.

methodsWe queried our Inherited Arrhythmia Registry and identified patients with LQTS who were on "submaximal" beta blocker doses (nadolol < 0.75-mg/kg/day & propranolol < 2 mg/kg/day) with at least 6 months follow up. Adequate beta blockade effect was defined as at least 15% decrease from maximal HR.

resultsThe study included 127 LQTS patients: 47% on maximal therapy, 43% on submaximal therapy, and 10% not receiving treatment. Thirty three percent of patients were on submaximal therapy due to side effects, none in patients less than 10 years of age. Baseline characteristics were similar between the groups. There was no significant difference in LTEs between maximal and submaximal therapy (8% vs. 5.4%, p = 0.72). During CPET, patients on maximal therapy were more likely to exhibit adequate chronotropic suppression (60% vs. 40%, p = 0.01). None of the patients on submaximal therapy with adequate chronotropic effect experienced LTEs during follow-up.

conclusionsAdequate chronotropic suppression was achieved with "submaximal" beta blocker dose in 40%. Despite similar baseline risk profiles, LTEs were not significantly different in patients with submaximal versus maximal therapy. CPET may be a useful modality to devise an individualized treatment plan, especially in those who cannot tolerate the recommended guideline directed dose.

Indexed as

Adrenergic beta-AntagonistsExercise TestHeart RateLong QT SyndromeNadololPropranololAdolescentAdultChildFemaleHumansMaleMiddle AgedPredictive Value of TestsRegistriesRetrospective StudiesAdrenergic beta-AntagonistsNadololPropranololcardiopulmonary exercise testinglong QT syndromenadolol

Identifiers

PMID40654199
PMCPMC12420871

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.