Pre-transplant ventricular assist device explant

Abstract

Explantation of a left ventricular assist device (LVAD) may be challenging even in the most experienced hands. We aim to describe the technique for explantation of an LVAD together with the heart as applicable to all contemporary implantable mechanical assist devices. In order to ensure safe explantation, particular care must be taken at three distinct stages: at the time of LVAD implantation, at pre-transplant assessment and at the time of heart transplantation. The preparation for a safe explantation at LVAD implantation includes positioning the driveline and the outflow graft away from the back of the sternum to ensure protection from injury during re-entry into the chest. At transplant assessment, essential investigations include computed tomography (CT) of the chest and ultrasound imaging of femoral vessels. At the time of heart transplantation, the site of peripheral access should be prepared and vessels exposed in case of a need for emergency bypass. We advise careful dissection starting from the lower aspect of the under surface of the sternum, moving as proximally as possible before attempting to use the oscillating saw. Much of the dissection of the heart is done off-pump. Cardiopulmonary bypass may be established either through peripheral vessels or the outflow graft in an emergency. Central direct cannulation is then established. After the heart and major vessels are isolated, explantation of the heart may begin either en-bloc or after splitting the ventricles in a sagittal plane. The basal regions of both ventricles and both atria are removed, leaving generous cuffs for anastomosis of the left atrium, pulmonary artery, aorta, inferior and superior vena cava (SVC). The apex of the heart is then removed with the device taking care not to injure the phrenic nerve.

Use of a Minimally Invasive Approach to Correct Diffuse External Compression of the Left Ventricular Assist Device Outflow Graft

“…Initial experiences with redo-sternotomies after LVAD implantation for heart transplant or LVAD exchange show dense adhesions between the outflow graft and the chest wall, as well as surrounding structures, like the right lung. 5 To protect against lung injury and subsequent severe air leaks as well as re-entry injury, many institutions adopted the practice of covering the Gelweave outflow graft with a Gore-Tex tubular graft. The reinforcement of the outflow graft using a Gore-Tex tube was also described and recommended for anastomosis of the outflow graft to sites other than the ascending aorta and for tunneling the outflow graft through the diaphragm.…”

The Diaphragm Muscle Manual Evaluation Scale

“…In the second clinical case, there was no clear lesion of the diaphragm; yet, the MED scale highlighted a respiratory problem on the left side. In the second patient, in addition to the weakness of the diaphragm, internal fibrous adhesions may be present in the pericardium, between the driveline and the diaphragm [10]. In patients with respiratory problems, the spirometry is a routine exam, but the forced expiratory volume in 1 second (FEV1) does not necessarily indicate the precise function of the diaphragm muscle or the presence/absence of dyspnea [11].…”

The role of ex-situ perfusion for thoracic organs

“…In addition to ethical concerns, prolonged period of warm ischemia yields the risk for more adverse events and worse outcomes, accordingly, seen with prolonged CIT [12,13]. Indeed, CIT greater than 4 h negatively affects both short-term and long-term survival; however, may be required especially for recipients pretreated with bypass or ventricular assist device [14,15 ▪ ,16].…”