Repolarization indicates electrical instability in ventricular arrhythmia originating from papillary muscle.
Europace
; 25(2): 688-697, 2023 02 16.
Article
in En
| MEDLINE
| ID: mdl-35989424
ABSTRACT
AIMS:
Cardiac arrhythmia originating from the papillary muscle (PM) can trigger ventricular fibrillation (VF) and cause sudden cardiac death even in the absence of structural heart disease. Most premature ventricular contractions, however, are benign and hitherto difficult to distinguish from a potentially fatal arrhythmia. Altered repolarization characteristics are associated with electrical instability, but electrophysiological changes which precede degeneration into VF are still not fully understood. METHODS ANDRESULTS:
Ventricular arrhythmia (VA) was induced by aconitine injection into PMs of healthy sheep. To investigate mechanisms of degeneration of stable VA into VF in structurally healthy hearts, endocardial high-density and epicardial mapping was performed during sinus rhythm (SR) and VA. The electrical restitution curve, modelling the relation of diastolic interval and activation recovery interval (a surrogate parameter for action potential duration), is steeper in VA than in non-arrhythmia (ventricular pacing and SR). Steeper restitution curves reflect electrical instability and propensity to degenerate into VF. Importantly, we find the parameter repolarization time in relation to cycle length (RT/CL) to differentiate self-limiting from degenerating arrhythmia with high specificity and sensitivity.CONCLUSION:
RT/CL may serve as a simple index to aid differentiation between self-limiting and electrically instable arrhythmia with the propensity to degenerate to VF. RT/CL is independent of cycle length and could easily be measured to identify electrical instability in patients.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Papillary Muscles
/
Arrhythmias, Cardiac
Type of study:
Prognostic_studies
Limits:
Animals
Language:
En
Journal:
Europace
Journal subject:
CARDIOLOGIA
/
FISIOLOGIA
Year:
2023
Document type:
Article
Affiliation country:
Germany
Publication country:
ENGLAND
/
ESCOCIA
/
GB
/
GREAT BRITAIN
/
INGLATERRA
/
REINO UNIDO
/
SCOTLAND
/
UK
/
UNITED KINGDOM