Abstract P181: Factors Associated with Implantable Cardioverter-Defibrillator Implantation
Introduction: While implantable cardioverter-defibrillators (ICDs) have been shown to reduce mortality in high risk populations (EF≤ 35%), the percentage of eligible candidates receiving ICDs has not been well studied. We sought to identify the clinical variables that were associated with ICD implants at our center.
Methods: Over a one year period (2005) we analyzed 13,920 echos and 3061 ventriculograms performed at our institution. Of these studies 4814 echos and 297 LV grams had EF≤ 35%. We randomly examined 5% of our echo data (200 echos) in the group with EF ≤ 35%. As a result, 497 patients were included in our initial combined analysis. Student T test and Chi-X testing was used for statistical analysis.
Results: Of these 497 patients, 145 patients were ultimately implanted. Pt characteristics that were associated with the implant group and were statistically significant include a history of; coronary heart disease (CAD) (p=0.04), congestive heart failure (p<0.001), coronary artery bypass surgery (CABG) (p=0.001), and ventricular tachycardia (VT) (non-sustained and sustained) (p=0.005). Pts with chronic renal insufficiency (creatinine >1.5 mg/dl) (p=0.03), and wide QRS complexes (≥ 130ms) (p<0 .001) were also associated with higher rate of implants. Patient medicines associated with ICD implant included; Aspirin (p=0.03), ACE inhibitor (p=0.009), statin (p=0.001), diuretic (p<0.001), oral hypoglycemic (p=0.02). Tobacco use was negatively correlated with implant of ICD (p=0.02).
Conclusions: At our center, ICD implant rates correlated positively in patients who have a history of CAD, CHF, CABG, chronic renal insufficiency, non-sustained/sustained VT, and wide QRS. ICD implants also correlate positively with patients on cardiac medications, which may identify populations with risk factors. Interestingly, ICD implants correlate negatively with tobacco use.