The fragility of cardiovascular clinical trial results

Novel approaches to clinical trials: device-related infections

The explosive growth in the use of cardiac devices and the continued large number of thoracic operations produce a significant number of costly infectious complications. These infections represent a leading cause of death and disability after device implantation or surgery. Unfortunately, few objective data are available to validate the clinical epidemiology of surgical and device-related infections, and although the number of randomized trials is increasing, too few have tested strategies for prophylaxis or treatment, particularly in the cardiac arena. Because of the expected increase in invasive vascular procedures and device implantations, it is timely to consider innovative approaches to clinical research that will hasten the translation of effective therapeutic strategies and technologies into clinical practice. Because of the multidisciplinary nature of the care of patients undergoing thoracic surgery or device implantation, bringing together existing networks and several arms of the Federal government could rapidly advance this field to provide a definitive base of evidence to guide clinical practice and improve clinical outcomes. The remainder of the articles in this supplement discuss specific issues on the diagnosis and treatment of device-related or surgical infection. The purpose of this manuscript is to discuss issues about the design of studies and their organization.

Randomized trial of a daily electronic home monitoring system in patients with advanced heart failure: the Weight Monitoring in Heart Failure (WHARF) trial

BACKGROUND

Heart failure treatment guidelines emphasize daily weight monitoring for patients with heart failure, but data to support this practice are lacking. Using a technology-based heart failure monitoring system, we determined whether daily reporting of weight and symptoms in patients with advanced heart failure would reduce rehospitalization and mortality rates despite aggressive guideline-driven heart failure care.

METHODS

This was a randomized, controlled trial. Patients hospitalized with New York Heart Association class III or IV heart failure, with a left ventricular ejection fraction < or =35% were randomized to receive heart failure program care or heart failure program care plus the AlereNet system (Alere Medical, Reno, Nev) and followed-up for 6 months. The primary end point was 6-month hospital readmission rate. Secondary end points included mortality, heart failure hospitalization readmission rate, emergency room visitation rate, and quality of life.

RESULTS

Two hundred eighty patients from 16 heart failure centers across the United States were randomized: 138 received the AlereNet system and 142 received standard care. Mean age was 59 +/- 15 years and 68% were male. The population had very advanced heart failure, New York Heart Association class III (75%) or IV (25%), as evidenced by serum norepinepherine levels, 6-minute walk distance and outcomes. No differences in hospitalization rates were observed. There was a 56.2% reduction in mortality (P <.003) for patients randomized to the AlereNet group.

CONCLUSIONS

This is the largest multicenter, randomized trial of a technology-based daily weight and symptom-monitoring system for patients with advanced heart failure. Despite no difference in the primary end point of rehospitalization rates, mortality was significantly reduced for patients randomized to the AlereNet system without an increase in utilization, despite specialized and aggressive heart failure care in both groups.