Research
Print page Print page
Switch language
The Capital Region of Denmark - a part of Copenhagen University Hospital
Published

Long QT syndrome type 1 and 2 patients respond differently to arrhythmic triggers: The TriQarr in vivo study

Research output: Contribution to journalJournal articleResearchpeer-review

  1. Nationwide burden of sudden cardiac death: A study of 54,028 deaths in Denmark

    Research output: Contribution to journalJournal articleResearchpeer-review

  2. Common and rare susceptibility genetic variants predisposing to Brugada syndrome in Thailand

    Research output: Contribution to journalJournal articleResearchpeer-review

  3. Amiodarone treatment in atrial fibrillation and the risk of incident cancers: a nationwide observational study

    Research output: Contribution to journalJournal articleResearchpeer-review

  1. Coagulation parameters in the newborn and infant - the Copenhagen Baby Heart and COMPARE studies

    Research output: Contribution to journalJournal articleResearchpeer-review

  2. Lipoprotein(a) levels at birth and in early childhood: The COMPARE Study

    Research output: Contribution to journalJournal articleResearchpeer-review

  3. Ticagrelor and the risk of Staphylococcus aureus bacteraemia and other infections

    Research output: Contribution to journalJournal articleResearchpeer-review

  4. Lung Ultrasound Findings Associated With COVID-19 ARDS, ICU Admission, and All-Cause Mortality

    Research output: Contribution to journalJournal articleResearchpeer-review

  5. Testing Denmark: a Danish Nationwide Surveillance Study of COVID-19

    Research output: Contribution to journalJournal articleResearchpeer-review

View graph of relations

BACKGROUND: In patients with long QT syndrome (LQTS), swimming and loud noises have been identified as genotype-specific arrhythmic triggers in LQTS type 1 (LQTS1) and LQTS type 2 (LQTS2), respectively.

OBJECTIVE: The purpose of this study was to compare LQTS group responses to arrhythmic triggers.

METHODS: LQTS1 and LQTS2 patients were included. Before and after beta-blocker intake, electrocardiograms were recorded as participants (1) were exposed to a loud noise of ∼100 dB; and (2) had their face immersed into cold water.

RESULTS: Twenty-three patients (9 LQTS1, 14 LQTS2) participated. In response to noise, LQTS groups showed similarly increased heart rate, but LQTS2 patients had corrected QT interval (Fridericia formula) (QTcF) prolonged significantly more than LQTS1 patients (37 ± 8 ms vs 15 ± 6 ms; P = .02). After intake of beta-blocker, QTcF prolongation in LQTS2 patients was significantly blunted and similar to that of LQTS1 patients (P = .90). In response to simulated diving, LQTS groups experienced a heart rate drop of ∼28 bpm, which shortened QTcF similarly in both groups. After intake of beta-blockers, heart rate dropped to 28 ± 2 bpm in LQTS1 patients and 20 ± 3 bpm in LQTS2, resulting in a slower heart rate in LQTS1 compared with LQTS2 (P = .01). In response, QTcF shortened similarly in LQTS1 and LQTS2 patients (57 ± 9 ms vs 36 ± 7 ms; P = .10).

CONCLUSION: When exposed to noise, LQTS2 patients had QTc prolonged significantly more than did LQTS1 patients. Importantly, beta-blockers reduced noise-induced QTc prolongation in LQTS2 patients, thus demonstrating the protective effect of beta-blockers. In response to simulated diving, LQTS groups responded similarly, but a slower heart rate was observed in LQTS1 patients during simulated diving after beta-blocker intake.

Original languageEnglish
JournalHeart Rhythm
Volume18
Issue number2
Pages (from-to)241-249
Number of pages9
ISSN1547-5271
DOIs
Publication statusPublished - Feb 2021

    Research areas

  • Auditory stimuli, Diving reflex, Loud noise, Ventricular arrhythmia

ID: 62031073