Utility of Intrathoracic Impedance Monitoring in Pediatric and Congenital Heart Disease

Abstract

The sensitivity and positive predictive value of intrathoracic impedance monitoring was low in this population of adult congenital and pediatric patients. Recent improvements to the OptiVol algorithm may decrease these deficiencies.

The Assessment of Intrathoracic Impedance Algorithm in the Pediatric and Adult Congenital Population

“…We read with interest the "Assessment of intrathoracic impedance algorithm in the pediatric and adult congenital heart population" by Silva et al, 1 particularly because the authors contrast our own paper on the subject. 2 Silva et al conclude, in their Medtronic-funded study, that Optivol (Medtronic Inc., Minneapolis, MN, USA)-an intrathoracic impedance monitoring feature in cardiac devices-has considerably greater utility than found in our own analysis. Our assessment of its value in a diverse pediatric/congenital cohort was that it did not properly identify clinically relevant events, and moreover that false-positives rendered the technology unhelpful.…”

“…We read with interest the “Assessment of intrathoracic impedance algorithm in the pediatric and adult congenital heart population” by Silva et al, particularly because the authors contrast our own paper on the subject . Silva et al.…”

Assessment of Intrathoracic Impedance Algorithm in the Pediatric and Adult Congenital Population

“…A set limit of 60 Ω day is programmed for the OptiVol® Fluid Index; when the index exceeds this number, the sensitivity of the algorithm for predicting HF hospitalization is 77% in adult patients with 1.5 false‐positive alerts noted per patient‐year of follow‐up . A recent single center study in pediatric and adult congenital patients evaluated the algorithm to have a sensitivity of 33% and positive predictive value (PPV) of <4.4%, well below the published data in the adult population.…”

“…There has been one recent report examining the OptiVol® algorithm in pediatric/adult CHD patients . Interestingly, there were few patients with cardiomyopathies enrolled in the study.…”

Results of remote follow-up and monitoring in young patients with cardiac implantable electronic devices

“…Indeed, the sensitivity and positive predictive value of OptiVol was shown to be low in a paediatric population with a low rate of systemic ventricular failure or with epicardial systems. 23 In the majority of cases, the knowledge of both patients and devices enabled technicians and physicians to recognise not clinically relevant problems or already known situations that did not require further investigations than those provided during scheduled outpatient visits. In addition, the CareLink system led to an earlier recognition of several clinically relevant eventsthat is, lead fracture, atrial or ventricular arrhythmiasallowing physicians to make quicker decisions.…”