Different predictive values of electrophysiological testing and autonomic assessment in patients surviving a sustained arrhythmic episode.
BACKGROUND
Recent data suggest that the electrophysiological study (EPS) has limited value in the identification of high risk patients, so the aim of the present study was to evaluate if non-invasive measurement of baroreflex sensitivity (BRS), a marker of autonomic balance, provides additional prognostic information in patients surviving a sustained arrhythmic episode.


RESULTS
The study group comprised 112 post myocardial infarction patients consecutively referred for EPS following documented ventricular fibrillation (VF) (20), sustained ventricular tachycardia (VT) (74) or a syncopal episode with subsequently documented non-sustained VT at Holter monitoring (18). BRS was assessed according to the transfer function method. A cardioverter - defibrillator (ICD) was implanted in 97 patients. During follow-up (median 315 days), appropriate ICD discharge occurred in 53 patients, and 3 more patients died suddenly. Sustained VT was induced in 84% and 77% of patients who did or did not develop arrhythmia at follow-up (p=0.34). No differences were found in age, sex, infarct site, drug therapy, resting RR interval or cycle of induced VT. Left ventricular ejection fraction (LVEF) < or =35%, New York Heart Association (NYHA) class >2 and BRS < or =3.3 ms/mmHg were found to be univariate predictors of arrhythmia recurrence. Multivariate models were obtained after grouping patients according to a moderately or severely depressed LVEF. Among the patients with LVEF < or =35%, BRS < or =3.3 ms/mmHg emerged as the only significant risk predictor of arrhythmia occurrence (sensitivity, specificity, positive and negative predictive value = 79%, 74%, 83% and 68%, respectively), whereas NYHA class >2 was a significant predictor among patients with LVEF >35%.


CONCLUSIONS
Noninvasive BRS, but not EPS, is of value in predicting VT/VF episode recurrence in patients surviving a major arrhythmic event.
Raczak
Grzegorz
G
II Department of Cardiology, Medical University of Gdańsk, Poland. gracz@amg.gda.pl
Pinna
Gian Domenico
GD
Maestri
Roberto
R
Daniłowicz-Szymanowicz
Ludmiła
L
Szwoch
Małgorzta
M
Lubinski
Andrzej
A
Kempa
Maciej
M
La Rovere
Maria Teresa
MT
Swiatecka
Grazyna
G
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000638:Amiodarone / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology*; D017704:Baroreflex / Q000502:physiology; D016757:Death, Sudden, Cardiac; D004594:Electrophysiology / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016019:Survival Analysis
D000319:Adrenergic beta-Antagonists; D000889:Anti-Arrhythmia Agents; D000638:Amiodarone