MedicalResearch.com Interview with: Dr. Alan Cheng, MD MBA Vice President at Medtronic Clinical Research and Therapy Development, Cardiac Rhythm Management Medtronic, Minnesota 55112  MedicalResearch.com: What is the background for this study? What are the main findings? Response: Ventricular arrhythmias can be life threatening among patients with certain types of heart disease. While implantable cardioverter defibrillators (ICDs) have become the primary means in managing these events, we still don’t fully understand when ventricular arrhythmias occur and whether they are just random events that occur at any time of the day. We pooled patient-level data from 6 prospective studies of ICD recipients and leveraged the continuous monitoring features of the ICD to understand when ventricular arrhythmias occur. Across almost 4000 patients with almost 2 years average follow up from the time of implant, we saw that ventricular arrhythmias aren’t randomly distributed throughout the day. In fact, there is a predilection for these events to occur during normal waking hours as compared to the times of the day when most patients are asleep. Additionally, we found that across the year, the spring season had higher rates of arrhythmia occurrence when compared to summer. We didn’t observe any differences in arrhythmia occurrence by the days of the week or months of the year. This analysis is not the first to explore this question but it is the largest to date.  (more…)