Title: Use of implanted CRT device diagnostics to determine the risk of heart failure decompensation
Abstract: Background: Newer implantable cardiac resynchronization therapy (CRT) devices are able to measure and record average night heart rate, heart rate variability and patient activity on a daily basis. The purpose of this retrospective analysis was to assess whether these device measures may be useful for managing patients with heart failure. Methods: We reviewed heart failure decompensation events which included heart failure hospitalizations in a study of CRT for NYHA III/IV heart failure pts without traditional pacing indications (U.S. InSync III trial). Device based heart failure diagnostics were not used to make clinical decisions. Two analyses were performed: 1) the average daily values from one month post implant to the six month follow-up for average night heart rate, heart rate variability and physical activity were compared for pts with and without heart failure decompensation and 2) the ability of night heart rate, heart rate variability and physical actvity to predict heart failure hospitalization was assessed by comparing the weekly average of weeks starting 1 week and 4 weeks prior to the heart failure hospitalization for patients with a hospitalization at least 40 days post implant. Results: Of the 255 patients for whom device data were available, 65 experienced at least one heart failure decompensation. There were 33 patients with a heart failure hospitalization at least 40 days post implant. There were no statistical differences in the following baseline characteristics between the Heart Failure Decompensation and No Heart Failure Decompensation groups (age, gender, etiology, NYHA, LVEF, LVEDD, beta blocker usage), while the No Heart Failure Decompensation group had a slightly wider QRS (167 ms vs. 160 ms, p = 0.02). As shown in the table, patients with Heart Failure Decompensation have higher average night heart rate, lower heart rate variability and less physical actvity, as measured by the device on a daily basis. Modest, but statistically significant, changes in heart rate variability and physical activity occur a week prior to hospitalization. Tabled 1DiagnosticNo Heart Failure DecompensationHeart Failure DecompensationP-valueHeart Failure Hospitalization -4 WeeksHeart Failure Hospitalization -1 WeekP-valueNight Heart Rate (bpm)69.8±9.375.2±9.90.000178.3±11.479.8±12.40.15Heart Rate Variability (ms)87.6±24.275.4±23.20.000866.5±21.160.6±24.40.03Physical Activity (hr)3.1±1.52.4±1.20.00032.6±1.22.1±1.10.005 Open table in a new tab Conclusions: CRT devices with these diagnostic capabilities may offer objective measures to help determine which patients warrant closer supervision of their heart failure status.
Publication Year: 2003
Publication Date: 2003-10-01
Language: en
Type: article
Indexed In: ['crossref']
Access and Citation
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot