Protection from outpatient sudden cardiac death following ICD removal using a wearable cardioverter defibrillator.

BACKGROUND: An implantable cardioverter defibrillator (ICD) is effective in preventing sudden cardiac death (SCD). Once an ICD is removed and reimplantation is not feasible, a wearable cardioverter defibrillator (WCD) may be an alternative option. We determined the effectiveness of WCD for SCD prevention in patients who were discharged after ICD removal. METHODS: A retrospective study was conducted on all WCD (LifeVest, ZOLL, Pittsburgh, PA, USA) patients who underwent ICD removal due to cardiac device infections (CDIs) at two referral centers between January 1, 2005 and December 31, 2009. Clinical characteristics, device information, and WCD data were analyzed. Sudden cardiac arrest was defined as all sustained ventricular tachycardia (VT) and ventricular fibrillation occurring within a single 24-hour period. RESULTS: Ninety-seven patients (mean age 62.8 ± 13.3, male 80.4%) were included in the study. The median duration of antibiotic use was 14.7 days (interquartile range [IQR] 10-30). The median daily WCD use was 20 hours/day and the median length of use was 21 days (IQR 5-47). A total of three patients were shocked by WCD. Two patients had four episodes of sustained VT, successfully terminated by the WCD. A third patient experienced two inappropriate treatments due to oversensitivity of the signal artifact. Three patients experienced sudden death outside the hospital while not wearing the device. Five patients died while hospitalized. CONCLUSION: WCD can prevent SCD, until ICD reimplantation is feasible in patients who underwent device removals for CDI. However, patient compliance is essential for the effective use of this device.

Recruiting vulnerable populations for research: revisiting the ethical issues.

The successful recruitment of participants is essential to the research process. To increase the rate of subject participation, investigators have to rely on help from health care providers who often serve as gatekeepers to potential research study subjects. These well-meaning professionals may limit subject participation in a study involving vulnerable populations under the guise of protecting these individuals from harm. We describe some of the characteristics of vulnerable populations affecting their recruitment into research studies. We examine the ethical conflicts that occur when health care professionals control access to these subjects during recruitment for research studies. Finally, we discuss the implications for practice and research designed to protect the rights of vulnerable populations participating in research. We identify collaboration and dialogue between researchers, health care providers, and members of the potential subject populations as most important in recruiting sufficient numbers of subjects to ensure the scientific merit of the study.