Dataset Information

Optogenetic termination of ventricular arrhythmias in the whole heart: towards biological cardiac rhythm management.

ABSTRACT:

Aims

Current treatments of ventricular arrhythmias rely on modulation of cardiac electrical function through drugs, ablation or electroshocks, which are all non-biological and rather unspecific, irreversible or traumatizing interventions. Optogenetics, however, is a novel, biological technique allowing electrical modulation in a specific, reversible and trauma-free manner using light-gated ion channels. The aim of our study was to investigate optogenetic termination of ventricular arrhythmias in the whole heart.

Methods and results

Systemic delivery of cardiotropic adeno-associated virus vectors, encoding the light-gated depolarizing ion channel red-activatable channelrhodopsin (ReaChR), resulted in global cardiomyocyte-restricted transgene expression in adult Wistar rat hearts allowing ReaChR-mediated depolarization and pacing. Next, ventricular tachyarrhythmias (VTs) were induced in the optogenetically modified hearts by burst pacing in a Langendorff setup, followed by programmed, local epicardial illumination. A single 470-nm light pulse (1000?ms, 2.97?mW/mm2) terminated 97% of monomorphic and 57% of polymorphic VTs vs. 0% without illumination, as assessed by electrocardiogram recordings. Optical mapping showed significant prolongation of voltage signals just before arrhythmia termination. Pharmacological action potential duration (APD) shortening almost fully inhibited light-induced arrhythmia termination indicating an important role for APD in this process.

Conclusion

Brief local epicardial illumination of the optogenetically modified adult rat heart allows contact- and shock-free termination of ventricular arrhythmias in an effective and repetitive manner after optogenetic modification. These findings could lay the basis for the development of fundamentally new and biological options for cardiac arrhythmia management.

SUBMITTER: Nyns ECA

PROVIDER: S-EPMC5837774 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Optogenetic termination of ventricular arrhythmias in the whole heart: towards biological cardiac rhythm management.

Nyns Emile C A ECA Kip Annemarie A Bart Cindy I CI Plomp Jaap J JJ Zeppenfeld Katja K Schalij Martin J MJ de Vries Antoine A F AAF Pijnappels Daniël A DA

European heart journal 20170701 27

<h4>Aims</h4>Current treatments of ventricular arrhythmias rely on modulation of cardiac electrical function through drugs, ablation or electroshocks, which are all non-biological and rather unspecific, irreversible or traumatizing interventions. Optogenetics, however, is a novel, biological technique allowing electrical modulation in a specific, reversible and trauma-free manner using light-gated ion channels. The aim of our study was to investigate optogenetic termination of ventricular arrhyt ...[more]

PMID: 28011703

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Dataset Information

Optogenetic termination of ventricular arrhythmias in the whole heart: towards biological cardiac rhythm management.

Aims

Methods and results

Conclusion

Publications

Optogenetic termination of ventricular arrhythmias in the whole heart: towards biological cardiac rhythm management.

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