Low level of daily physical activity was associated with a higher risk of atrial arrhythmias in heart failure patients with implantable devices. A low level of baseline physical activity was also associated with a higher risk of death of heart failure related hospitalisation. These are the results of the IMPLANTED (Italian Multicentre Observational Registry on Patients with Implantable Devices Remotely Monitored) study. These results could help physicians to predict atrial arrhythmic episodes and improving outcomes.
The study set out to look at whether daily physical activity, as measured by implanted devices (through accelerometer sensor), was related to the risk of developing atrial arrhythmias during long‐term follow‐up in a population of heart failure (HF) patients with an implantable cardioverter defibrillator (ICD).
IMPLANTED was a multicentre retrospective registry and enrolled patients from seven Italian high-volume arrhythmia centres. The patients were all aged over 18 years and underwent pacemaker or ICD implantation between January 2009 and September 2016. All of the patients enrolled in the study received an ICD equipped with remote monitoring capabilities.
Of the 1,107 patients enrolled in the IMPLANTED registry, 770 were eligible for analysis. The study population was divided into two equally sized groups (physical activity cut-off point: 3.5 hours per day) according to their mean daily physical activity as recorded by the device during the 30‐ to 60‐day period post‐ICD implantation. Propensity score matching was used to compare two equally sized cohorts with similar characteristics between lower and higher activity patients. The primary end point was time free from the first atrial high‐rate episode (AHRE) of duration ≥6 minutes. Secondary end points were: first AHRE ≥6 hours, first AHRE ≥48 hours, and a combined end point of death or heart failure hospitalisation. Data from 770 patients (65±15 years; 66% men; left ventricular ejection fraction 35±12%) who were remotely monitored for a median of 25 months was analysed.
Physical activity of more than three and a half hours per day was associated with a 38% relative reduction (compared to lower levels of physical activity) in the risk of atrial high rate episode of six minutes or more (72‐month cumulative survival: 75.0% versus 68.1%; log rank P=0.025), and with a reduction in the risk of AHRE ≥6 hours, AHRE ≥48 hours, and the combined end point of death or heart failure hospitalisation (all P<0.05).
The results of this study confirm the evidence from several other studies and show that a baseline daily physical activity level of less than three and a half hours a day is significantly associated with a higher risk of death or heart failure hospitalisation and of heart failure hospitalisation alone, even after correction for disease severity.