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[Ventricular arrhythmia and late potentials in patients with hypertrophic cardiomyopathy]
C Fleischmann1, B D Gonska, S Brune
1Medizinische Universitätsklinik Göttingen, Abteilung Kardologie und Pulmonologie.
Insights
Hypertrophic cardiomyopathy patients frequently experience ventricular arrhythmias, including premature beats and occasional ventricular tachycardia. Signal-averaged late potentials, indicative of arrhythmia risk, were present in a subset of these patients.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Diagnostics
Context:
- Hypertrophic cardiomyopathy (HCM) is a complex cardiac condition.
- Assessing arrhythmia risk is crucial for managing HCM patients.
- Holter monitoring and signal-averaged late potentials are key diagnostic tools.
Purpose:
- To investigate the prevalence of spontaneous ventricular arrhythmias in HCM patients.
- To evaluate the utility of signal-averaged late potentials in identifying patients at risk.
- To correlate electrophysiological findings with clinical presentation.
Summary:
- This study monitored 45 hypertrophic cardiomyopathy patients (without antiarrhythmic drugs) using 48-hour Holter and signal-averaged late potentials.
- High prevalence of ventricular arrhythmias observed: 96% had premature beats, 76% multiform extrasystoles, 27% ectopic pairs, and 20% ventricular tachycardia.
- Late potentials were identified in 4 out of 28 evaluable patients based on specific QRS duration, low amplitude signal duration, and amplitude criteria.
Impact:
- Findings highlight the significant burden of ventricular arrhythmias in HCM.
- Identifies signal-averaged late potentials as a potential, albeit less common, marker for arrhythmia risk in HCM.
- Informs clinical practice regarding comprehensive arrhythmia assessment in hypertrophic cardiomyopathy.
Abstract:
Holter monitoring (48 h) and registration of signal-averaged late potentials (method of Simson, high pass filter 40 Hz) were performed in outpatiens with hypertrophic cardiomyopathy. A prevalence of spontaneous ventricular arrhythmias could be determined in 51 patients; the results of 45 patients not taking antiarrhythmic drugs are presented here. 96% of these showed ventricular premature beats, 76% had multiform extrasystoles, 27% showed pairs of ectopic beats and 20% had runs of ventricular tachycardia (more than 3 QRS complexes). Absolute counts of premature beats were low in most patients, but important interindividual differences could be observed: M = 34 extrasystoles/24 h (0-4943). Ventricular tachycardias were of short duration (maximum 11 QRS) with heart rate ranging from 120 to 200/min. All patients were asymptomatic during tachycardia. Signal-averaged late potentials could be registered in 30 patients, 28 of them without antiarrhythmic drug therapy. Mean QRS duration (QRSdur) was 108 +/- 12 ms, mean duration of low amplitude signals (less than 40 microV) in the terminal portion of the QRS (LAdur) was 27 +/- 13 ms, and mean amplitude of the last 40 ms of the filtered QRS (LAamp) was 65 +/- 43 microV. A patient was considered to show late potentials if two of the following criteria were present: QRSdur greater than 120 ms, LAdur greater than or equal to 40 ms, LAamp less than 20 microV. This was found in four patients.(ABSTRACT TRUNCATED AT 250 WORDS)