Is hemodynamic transesophageal echocardiography needed for patients with left ventricular assist device?

BACKGROUND: Interventions in patients with a left ventricular assist device (LVAD) in the intensive care unit (ICU) are typically performed based on the results of conventional monitoring, such as vital signs and Swan-Ganz catheter (SGC) and LVAD parameters. These variables might not always accurately reflect a patient's cardiac function, volume status, and interventricular septal configuration, however. To assess the accuracy of standard monitoring, we performed routine continuous hemodynamic transesophageal echocardiography (hTEE) to evaluate cardiac function, volume status, and septal position.

METHODS: Between 2011 and 2015, 93 HeartMate II LVADs were implanted. The study group comprised 30 patients with an SGC in place who were monitored routinely by hTEE in the ICU every 1 to 3 hours until extubation. A total of 147 hTEE studies were analyzed retrospectively to observe differences between conventional monitoring and hTEE.

RESULTS: Among the 30 patients studied, 26 (87%) had at least 1 disagreement between conventional monitoring and hTEE findings. In 22 patients (73%), at least 1 of the hTEE studies was abnormal whereas conventional parameters were normal. Abnormal hTEE findings included a shift in the interventricular septum in 19 patients (63%), abnormal ventricular volume status in 22 patients (73%), and right ventricular failure in 9 patients (30%). Based on conventional monitoring, none of the patients required an LVAD speed change, whereas hTEE showed that 14 patients (47%) needed an LVAD speed adjustment.

CONCLUSIONS: Conventional monitoring in the ICU might not provide an accurate representation of cardiac function, ventricular volume status, or septal position in patients with LVAD. Continuous monitoring with hTEE in patients with an LVAD may help guide optimal intervention in the ICU setting during the early postoperative period.