Inappropriate implantable cardioverter- defibrillator(ICD)shocks continue to be a major source of distress to patients and a drain on the health care system. Expanding indications for ICD implantation include a large ...Inappropriate implantable cardioverter- defibrillator(ICD)shocks continue to be a major source of distress to patients and a drain on the health care system. Expanding indications for ICD implantation include a large portion of patients with heart failure. This study investigated the relation between inappropriate ICD shocks and the severity of heart failure symptoms. Predictors of the time to first inappropriate ICD therapy were investigated in 230 consecutive patients implanted in 2001 and 2002. Thirty- two patients received 42 inappropriate shocks during a median follow- up of 501 days. Inappropriate shocks were due to atrial fibrillation(AF) or tachycardia(n=31), other supraventricular tachycardias(n=6), sinus tachycardia(n=3), and noise or double counting(n=2). The time to first inappropriate ICD shock was earliest in patients with advanced classes of heart failure(1- and 2- year shock- free survival of 79% and 70% for patients in New York Heart Association [NYHA] class III or IV vs 92% and 88% for patients in NYHA class I or II, respectively, p=0.02). After correcting for age, gender, the presence of coronary artery disease, the presence of AF, the use of β blockers, and indication for ICD implantation in a Cox regression model, advanced heart failure(NYHA class III or IV) remained an independent predictor of first inappropriate ICD shocks(hazard ratio 2.7, p=0.01). Other predictors of the time to first inappropriate ICD shock included the presence of AF as the baseline rhythm at the time of the ICD implantation and the absence of coronary disease. In conclusion, inappropriate ICD shocks are predominantly due to AF. Advanced heart failure is an independent predictor of the time to first inappropriate ICD shocks. The effect of ICD programming and antiarrhythmic drug therapy on the incidence of inappropriate shocks deserves further investigation.展开更多
Background: Indications for implantable cardioverter defibrillator(ICD) implantation are expanding, but many primary and secondary ICD trials have excluded patients with advanced renal insufficiency. We investigated t...Background: Indications for implantable cardioverter defibrillator(ICD) implantation are expanding, but many primary and secondary ICD trials have excluded patients with advanced renal insufficiency. We investigated the effect of renal function on the incidence and time to first appropriate ICD shock. Method: We analyzed data from all new ICD implantations at a tertiary care center from July 2001 to December 2002. Results: During a mean follow-up time of 445±285 days, 29(13%) of 230 patients(age 63±14 years, 79%men, 77%white, 75%coronary artery disease, left ventricular ejection fraction 0.28±0.14) received 41 appropriate shocks. Patients were divided into tertiles according to their serum creatinine level. The 1-year incidence of appropriate ICD shock was 3.8%, 10.8%, and 22.7%in the first, second, and third tertiles, respectively(P=.003). Using the same cut off values of serum creatinine, the 1-year incidence of appropriate ICD therapy(shock and antitachycardia pacing)was 8.8%, 20.8%, and 26.3%(P=.02). After correcting for age, sex, race, left ventricular ejection fraction, indication for ICD implantation, and use of β-blockers in a Cox regression model, serum creatinine was still an independent predictor of the time to first appropriate ICD shock(hazard ratio 6.0 for the third compared with the first tertile, P=.001). Conclusion: Renal insufficiency is a strong predictor of appropriate ICD shocks. Defibrillator therapy should therefore not be withheld based on the presence of this comorbidity. The mechanisms underlying the relationship between renal function and ventricular arrhythmias deserve further investigation.展开更多
文摘Inappropriate implantable cardioverter- defibrillator(ICD)shocks continue to be a major source of distress to patients and a drain on the health care system. Expanding indications for ICD implantation include a large portion of patients with heart failure. This study investigated the relation between inappropriate ICD shocks and the severity of heart failure symptoms. Predictors of the time to first inappropriate ICD therapy were investigated in 230 consecutive patients implanted in 2001 and 2002. Thirty- two patients received 42 inappropriate shocks during a median follow- up of 501 days. Inappropriate shocks were due to atrial fibrillation(AF) or tachycardia(n=31), other supraventricular tachycardias(n=6), sinus tachycardia(n=3), and noise or double counting(n=2). The time to first inappropriate ICD shock was earliest in patients with advanced classes of heart failure(1- and 2- year shock- free survival of 79% and 70% for patients in New York Heart Association [NYHA] class III or IV vs 92% and 88% for patients in NYHA class I or II, respectively, p=0.02). After correcting for age, gender, the presence of coronary artery disease, the presence of AF, the use of β blockers, and indication for ICD implantation in a Cox regression model, advanced heart failure(NYHA class III or IV) remained an independent predictor of first inappropriate ICD shocks(hazard ratio 2.7, p=0.01). Other predictors of the time to first inappropriate ICD shock included the presence of AF as the baseline rhythm at the time of the ICD implantation and the absence of coronary disease. In conclusion, inappropriate ICD shocks are predominantly due to AF. Advanced heart failure is an independent predictor of the time to first inappropriate ICD shocks. The effect of ICD programming and antiarrhythmic drug therapy on the incidence of inappropriate shocks deserves further investigation.
文摘Background: Indications for implantable cardioverter defibrillator(ICD) implantation are expanding, but many primary and secondary ICD trials have excluded patients with advanced renal insufficiency. We investigated the effect of renal function on the incidence and time to first appropriate ICD shock. Method: We analyzed data from all new ICD implantations at a tertiary care center from July 2001 to December 2002. Results: During a mean follow-up time of 445±285 days, 29(13%) of 230 patients(age 63±14 years, 79%men, 77%white, 75%coronary artery disease, left ventricular ejection fraction 0.28±0.14) received 41 appropriate shocks. Patients were divided into tertiles according to their serum creatinine level. The 1-year incidence of appropriate ICD shock was 3.8%, 10.8%, and 22.7%in the first, second, and third tertiles, respectively(P=.003). Using the same cut off values of serum creatinine, the 1-year incidence of appropriate ICD therapy(shock and antitachycardia pacing)was 8.8%, 20.8%, and 26.3%(P=.02). After correcting for age, sex, race, left ventricular ejection fraction, indication for ICD implantation, and use of β-blockers in a Cox regression model, serum creatinine was still an independent predictor of the time to first appropriate ICD shock(hazard ratio 6.0 for the third compared with the first tertile, P=.001). Conclusion: Renal insufficiency is a strong predictor of appropriate ICD shocks. Defibrillator therapy should therefore not be withheld based on the presence of this comorbidity. The mechanisms underlying the relationship between renal function and ventricular arrhythmias deserve further investigation.
