Persistently abnormal device-detected thoracic impedance and OptiVol fluid index related to breast reconstruction surgery.

With significant correlation shown between intrathoracic impedance and intrathoracic fluid volume, the utility of OptiVol fluid index (Medtronic, Minneapolis, MN, USA) in the management of patients with heart failure has been well-described. Although intrathoracic impedance is mainly affected by the changes in the intrathoracic fluid volume, a "false-positive" OptiVol fluid index can occur in the absence of overt congestive heart failure. We present a case of false positive Optivol fluid index elevation in a woman following breast reconstruction surgery.