Abstract 2716: What are the Current ICD Implant Patterns Since Expansion of Primary Indications and Support for Cardiac Resynchronization therapy? Data from a Large Multicenter Prospective Registry
With the publication of MADIT II in 2002 and SCD-HeFT in 2004, primary device implant indications have expanded; and with the COMPANION trial in 2005 supporting the benefit of biventricular devices, the number of ICD implants has increased further. Since these trials, data on implant patterns in a large group of patients from multiple centers has not been reported. The Advancements in ICD Therapy (ACT) prospective implant registry is a non-consecutive patient study developed to track such a group undergoing device implantation. Data on device and lead performance, arrhythmic events and mortality are tracked.
Methods: Over a 19 month period from November 2004.to June, 2006, 5454 devices were implanted at 286 centers in 38 states in the United States. Patients where enrolled within 2 weeks of implant. Patients are being followed for a period of 2 years at 6 month intervals with device interrogations performed at each visit. Primary prevention patients are those who met MADIT II, SCD-HeFT or DEFINITE criteria as well as those with inheritable conditions.
Results: Of the 5,454 patients, 402 had generator replacements and are excluded from this report. There where 464 device upgrades. Of the 4578 evaluable patients undergoing first implantation, 3,629 (79.3%) were for a primary prevention indication, and 20.7% for a secondary prevention indication. Biventricular devices were implanted in 1,905 patients (37.7% of total) with 135 of these being device upgrades. Male patients constitute 75.3% (n = 3,806) of the implant group and the median age at enrollment was 67 years. Median patient ejection fraction was 16%, (Interquartile Range 11% to 21%), with 88.6% having ejection fractions ≤ 35%, reflecting a fairly ill cohort.
In a current large, multicenter ICD implant registry, the overwhelming majority of patients underwent ICD implantation for a primary prevention indication.
Cardiac resynchronization therapy devices were implanted in approximately one third of the patients
Even with expanded indications for implantation, this is a patient cohort with apparent advanced disease states evidenced by their low ejection fractions.