Survey of current practices in use of amiodarone and implantable cardioverter defibrillators in pediatric patients with end-stage heart failure.

S tudies have shown that many adult patients still do not receive optimal heart failure management. Thus, given the absence of pediatric-specific clinical trails, it is possible that many of these new modalities are underutilized in pediatric patients with heart failure. We were interested as to whether these new approaches to diagnosis and therapy of adults with heart failure have been translated into pediatric practice in high-risk patients. To characterize current practice standards, we surveyed pediatric cardiologists at institutions involved in the care of children with endstage heart failure. • • • A survey on the use of implantable cardioverterdefibrillators (ICD), amiodarone therapy, and risk assessment for children with advanced heart failure was distributed to members of the Pediatric Heart Transplant Study Group and to members of the Pediatric Electrophysiology Society. A total of 44 institutions were surveyed. The questionnaire consisted of 13 questions that examined how pediatric cardiologists risk stratify and treat pediatric patients with arrhythmias and end-stage heart failure. Physicians were queried with regard to indications they employed for amiodarone and ICD therapy, the effect of patient age on these indications, and how many patients they treated. A total of 25 replies were received from 20 institutions, 18 of which were from electrophysiologists. Data routinely used for risk stratification in patients with end-stage heart failure was uniform among respondents with respect to use of electrocardiograms and Holter monitoring (96%) and exercise testing (80%), whereas the role of elecrophysiologic study was controversial (40% utilization). Use of heart rate variability analysis, QT dispersion measurement, or T-wave alternans was much less common, with only 6 respondents using any of these techniques. In patients with either syncope or resuscitated cardiac arrest, the use of electrophysiologic study was considerably higher (100% and 84%, respectively). Tilt-table testing was utilized in 11 of 25 respondents (44%) for patients with syncope. Of the survey respondents, 32% managed patients with failing congenital heart disease differently than those with pure cardiomyopathy and no structural abnormalities, usually in a more aggressive fashion. Intravenous amiodarone was used frequently by 15% of respondents, occasionally by 77%, and was never used by 8%. Oral amiodarone therapy was even more commonly used: 31% of respondents used it frequently, whereas 69% used it occasionally. The most common indications for amiodarone therapy are listed in Table 1. Utilization of amiodarone was not dependent upon patient age. ICD therapy was employed less frequently than amiodarone. ICDs were used frequently in pretransplant candidates by 4% of the respondents, occasionally by 81%, and never by 15%. In the 15% of respondents who did not use an ICD, 1 believed it was not a useful therapy, whereas 4 respondents had no patients whom they considered to be appropriate candidates. Most of the respondents (58%) were following between 1 and 5 patients with an ICD at the time of the survey, whereas 8% were following 11 with an ICD. ICDs were used in patients of various ages: 31% of respondents indicated that they had implanted an ICD in a patient 2 years of age, whereas for 38%, the minimum age of implantation was 5 years. Most respondents believed that there was no age cutoff as to the appropriateness of an ICD (84%), whereas a minority of 16% would not place an ICD in a patient 2 years old. No program had written guidelines for ICD implantation in this population. Most institutions decided on ICD therapy on a case-by-case basis. The most common indications for ICD implantation in children with advanced heart failure are listed in Table 1. Resuscitated cardiac arrest was an indication for ICD implantation for 23 of 25 respondents but was less commonly regarded as an indication for amiodarone therapy (17 of 25, p 0.03). Documented ventricular tachycardia had the opposite response from the participants; it was an indication for ICD in only 17 of 25 respondents, whereas 23 of 25 respondents regarded it as an indication for amiodarone (p 0.04). A positive electrophysiologic test was an indication for amiodarone more often than an indication for ICD (19 of 25 vs 14 of 25 respondents, p 0.001). • • • Arrhythmia is a major cause of morbidity and mortality in pediatric patients with end-stage heart failure. In patients with dilated cardiomyopathy, between 50% and 63% of children who die have ventricular arrhythmias at presentation. We recently showed that in pediatric patients awaiting transplantation, 62% had life-threatening arrhythmias, most commonly ventricular tachycardia. From Stanford University, Stanford, California and University of California at San Francisco, San Francisco, California. Dr. Dubin’s address is: 750 Welch Rd., Suite 305, Palo Alto, California 94304. E-mail: amdubin@leland.stanford.edu. Manuscript received January 12, 2001; revised manuscript received and accepted May 23, 2001.