Early- and Late-Onset Arrhythmias after Bioelectrical Impedance Analysis in End-Stage Heart Failure Patients under Inotropic Support

Purpose Bioelectrical impedance analysis (BIA) is a painless and safe way to measure body composition without radiation. It is feasible in immobile patients and may serve as a measure to assess frailty. BIA may lead to electromagnetic interference with the conduction system of the heart, provoking oversensing in pacemakers and internal cardiac defibrillators or arrhythmias. End-stage heart failure patients are at highest risk for these possible side effects. The aim of this study was to evaluate the safety of BIA in end-stage heart failure patients under pro-arrhythmogenic pharmacologic therapy. Methods We performed 56 BIA measurements in 32 hospitalized patients (28 male, 4 female), suffering from advanced heart failure (20 DCMP; 10 ICMP; 2 other) under constant ECG monitoring. Fourteen measurements were performed while the patient was in need of single inotropic support (9 dobutamine; 5 milrinone), 11 patients received combined inotropic therapy (7 milrinone/dobutamine; 1 dobutamine/noradrenalin; 1 dobutamine/adrenalin; 2 dobutamine, milrinone, noradrenalin, adrenalin). Their mean Inotropic Score was 10.03 (+/- 7.15). During 31 BIA measurements, the patient had an implantable cardiac device (ICD, pacemaker or CRT) in place; one patient had an external defibrillator (LifeVest). Thirty-eight BIA measurements were performed while the patient was receiving antiarrhythmic medication either with amiodarone (15), beta-blockers (26), sotalol (1) or glycosides (4) alone (34) or in combination (4). Eighteen assessments were performed without any antiarrhythmic medication. During 36 assessments, the patient received supplementary potassium and during 12 evaluations, the patient was treated with other medication such as ivabradine or magnesium. Results None of the patients showed any signs of clinically relevant arrhythmias following the BIA under ECG monitoring for 48 hours, but we observed some, probably coincidental, ventricular extrasystoles. No device malfunction was seen, especially no oversensing in ICDs resulting in inadequate shocks. Conclusion BIA measurement can be performed safely in end-stage heart failure patients with pro-arrhythmogenic pharmacologic therapy, who are the most vulnerable to arrhythmias.