Electrophysiological study and 'slow' ventricular tachycardia predict appropriate therapy: results from a single-centre implantable cardiac defibrillator follow-up.
OBJECTIVE
To account for appropriate and inappropriate therapies and cardiac death (CD) in a cohort of consecutive implantable cardiac defibrillator (ICD) eligible patients and to identify baseline predictors of these outcomes.


RESULTS
During follow-up of 288 consecutive ICD-treated patients, clinical, biochemical, echocardiographic, arteriographic, and electrophysiological (EP) data at baseline were individually matched with survival data and electrograms retrieved during device interrogation. Predictors of therapy and CD were identified by multivariate analyses. Eighty-eight per cent of cases were secondary prevention and 12% were primary prevention. About 770 patient-years of ICD follow-up were analysed. Median follow-up was 22.7 months. Forty-eight per cent of patients had appropriate therapy for at least one ventricular tachyarrhythmia. Seventy per cent of tachycardias were successfully treated with anti-tachy pacing alone. Overall risk of therapy was higher for patients with ischaemic heart disease (IHD) than with non-IHD (51 vs. 37%; P = 0.049). Low left ventricular ejection fraction (LVEF), positive EP study, and 'slow' ventricular tachycardia predicted appropriate therapy. Cardiac death was predicted by nephropathy, low LVEF, amiodarone use, and supraventricular tachycardia (SVT). Inappropriate therapy affected 12.2% of patients and was predicted by known SVT and IHD.


CONCLUSIONS
Electrophysiological study and slow VT predicted appropriate therapy. Amiodarone use predicted CD. Inappropriate therapy remains an important issue largely predictable by SVT.
Worck
René
R
Cardiology Clinic Y, University Hospital Bispebjerg, Bispebjerg Bakke 23, DK-2400 Copenhagen NV, Denmark. rw04@bbh.regionh.dk
Haarbo
Jens
J
Thomsen
Poul Erik Bloch
PE
D016170:Accelerated Idioventricular Rhythm / Q000503:physiopathology* / Q000628:therapy*; D000368:Aged; D000369:Aged, 80 and over; D000638:Amiodarone / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D016757:Death, Sudden, Cardiac / Q000209:etiology; D017147:Defibrillators, Implantable; D004594:Electrophysiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D012307:Risk Factors; D013318:Stroke Volume / Q000502:physiology; D016896:Treatment Outcome
D000889:Anti-Arrhythmia Agents; D000638:Amiodarone