Abstract
Introduction
The ANZACS-QI DEVICE registry is a national registry designed to collect data on all cardiac implantable electronic devices (CIED) implanted in New Zealand (NZ). This study aims to provide a contemporary analysis of the clinical characteristics and implant details of patients receiving implantable cardioverter defibrillator (ICD) and cardiac resynchronisation therapy (CRT), including CRT-Pacemaker (CRT-P) and CRT-Defibrillator (CRT-D).
Methods
Complete datasets of ICD, CRT-D and CRT-P implants from the ANZACS-QI DEVICE registry from 1st January 2014 to 31st December 2017 were analysed.
Results
A total of 1579 ICD implants were identified. Of the 1152 (73.0%) new implants, 565 (49.0%) were for primary prevention and 587 (51.0%) were for secondary prevention. The baseline demographics of both groups were similar, with a median age of 62 and predominantly male (79.2-81.4%), with European (63.7-66.8%) and Maori (21.1-24.8%) being the most common ethnicities. The mean BMI was 29.6-30.2 kg/m², with most patients (75.2-80.7%) being in sinus rhythm at the time of ICD implant. Compared to the secondary prevention group, the primary prevention group had more patients with a history of heart failure (80.4% vs 39.7%), worse heart failure symptoms (NYHA Class II-III 77.1% vs 47.3%), poorer left ventricular ejection fraction (LVEF) (mean 25.1% vs 30.3%) and the aetiology was more likely to be non-ischaemic (57.5% vs 44.2%). The mean QRS duration was longer (129.9ms vs 113.4ms), with a higher incidence of left bundle branch block (31.9% vs 16.0%) and a correspondingly higher rate of CRT-D implants (27.4% vs 8.3%).
In the 427 (27.0%) ICD replacements, over a mean duration of 6.27 years, 46.6% had delivered appropriate therapy (including 38.4% with appropriate ICD shocks) whilst 17.8% had delivered inappropriate therapy.
Compared to primary prevention CRT-D (n = 155), patients receiving CRT-P (n = 175) were older (median age 74 vs 66) and more likely to be female (38.3% vs 19.4%). CRT-D patients had longer mean QRS duration (169.2ms vs 160.8ms) and poorer LVEF (mean 24.3% vs 28.7%).
Conclusion
This analysis provides contemporary data on ICD and CRT use in New Zealand. Primary prevention ICD patients were more likely to have a history of heart failure, worse heart failure symptoms, more prolonged QRS duration, left bundle branch block and poorer LV function compared to secondary prevention ICD. Compared to primary prevention CRT-D, patients receiving CRT-P were older and more likely to be female.
169-07: Long term changes in transmural dispersion of repolarisation in patients with heart failure after cardiac resynchronisation therapy- A prospective study
