Adjustments of heart failure medication after implantation of a cardiac resynchronization therapy defibrillator.

AIM

"Optimal" medical therapy is mandatory before implantation of a cardiac resynchronization therapy (CRT) device, but "optimal" is not further specified. We determined the number of patients on a specific drug, the percentages of recommended target doses of the drugs the patients were on and their evolution over time.

METHODS

Drug therapy (ACE-inhibitors (ACE-I), AT-receptor antagonists (ARBs), betablockers) of 140 patients with a follow-up of at least one year was studied. Response to CRT was defined as reduction in NYHA class ≥1.

RESULTS

Age was 66±9 years, follow-up 43±25 months during which 28 patients (20%) had died. At baseline, 81 % of patients were on a betablocker compared to 95% after 3 years (P-value 0.02). Percentages of target doses were 55±34% and increased to 68±41% after 3 years (P-value <0.02). Percentages were increased in responders (58±40% to 72±32%, P-value 0.01 after 3 years), but not in non-responders (57±31% to 56±38%). At baseline, 97% of patients were on ACE-Is/ARBs and 100% after 3 years. Mean percentages of target doses were 78±43% at implant and between 73±40% and 79±49% during follow-up. Percentages were stable both in responders (83% at implant, 78% after 3 years) and in non-responders (80%/87%, both P-value n.s.).

CONCLUSION

Even though quantity and quality of drug therapy at baseline was on an acceptable (betablockers) or high (ACE-Is/ARBs) level, physicians must be very observant on therapy during long-term follow-up, especially on target doses of betablockers in non-responders.