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Off-Pump Implant of the Jarvik 2000 Ventricular Assist Device Through Median Sternotomy

2007; Elsevier BV; Volume: 84; Issue: 4 Linguagem: Inglês

10.1016/j.athoracsur.2007.02.004

1552-6259

Ani C. Anyanwu, Gregory W. Fischer, Irina Plotkina, Sean Pinney, David Adams,

Cardiac Structural Anomalies and Repair

Implantation of a left ventricular assist device through a median sternotomy usually requires cardiopulmonary bypass. However, the biological response to cardiopulmonary bypass is sometimes deleterious in end-stage heart failure patients, as it may compound pre-existing coagulopathy or multiorgan dysfunction. Therefore, there are potential advantages to avoiding cardiopulmonary bypass during left ventricular assist device placement. We describe a technique for off-pump implantation of the Jarvik 2000 left ventricular assist device (Jarvik Heart Inc, New York, NY) through a median sternotomy. Implantation of a left ventricular assist device through a median sternotomy usually requires cardiopulmonary bypass. However, the biological response to cardiopulmonary bypass is sometimes deleterious in end-stage heart failure patients, as it may compound pre-existing coagulopathy or multiorgan dysfunction. Therefore, there are potential advantages to avoiding cardiopulmonary bypass during left ventricular assist device placement. We describe a technique for off-pump implantation of the Jarvik 2000 left ventricular assist device (Jarvik Heart Inc, New York, NY) through a median sternotomy. As with other left ventricular assist devices (LVAD), the standard technique for insertion of the Jarvik 2000 LVAD (Jarvik Heart Inc, New York, NY) requires cardiopulmonary bypass (CPB) [1Westaby S. Frazier O.H. Pigott D.W. Saito S. Jarvik R.K. Implant technique for the Jarvik 2000 Heart.Ann Thorac Surg. 2002; 73: 1337-1340Abstract Full Text Full Text PDF PubMed Scopus (46) Google Scholar]. Because CPB has multiple systemic effects that compound the multiorgan dysfunction and coagulopathy that often pre-exists in LVAD patients, investigators have worked to reduce exposure to CPB during LVAD implantation. Notably, Frazier [2Frazier O.H. Implantation of the Jarvik 2000 left ventricular assist device without the use of cardiopulmonary bypass.Ann Thorac Surg. 2003; 75: 1028-1030Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar] and Frazier and colleagues [3Frazier O.H. Gregoric I.D. Cohn W.E. Initial experience with non-thoracic, extraperitoneal, off-pump insertion of the Jarvik 2000 Heart in patients with previous median sternotomy.J Heart Lung Transplant. 2006; 25: 499-503Abstract Full Text Full Text PDF PubMed Scopus (44) Google Scholar] have developed techniques for off-pump implantation of the Jarvik 2000 through a left thoracotomy and subcostal incisions, respectively, and Piacentino and coworkers [4Piacentino 3rd, V. Jones J. Fisher C.A. et al.Off-pump technique for insertion of a HeartMate Vented Electric left ventricular assist device.J Thorac Cardiovasc Surg. 2004; 127: 262-264Abstract Full Text Full Text PDF PubMed Scopus (4) Google Scholar] have developed a technique for the off-pump implantation of the Heartmate XVE (Thoratec Corp, Pleasanton, CA). However, the off-pump Jarvik 2000 implantation is not undertaken through a sternotomy because of relative inaccessibility of the cardiac apex. We report a successful case of off-pump implantation of the Jarvik 2000 through a median sternotomy. The patient was a 58-year-old man with nonischemic dilated cardiomyopathy who had been maintained on a continuous infusion of milrinone while awaiting cardiac transplantation. He was 185 cm tall, blood type O, and had not undergone prior cardiac surgery. He became increasingly decompensated, despite inotropic therapy, also with increasing serum creatinine (peak, 2.8 mg/dL). He was referred for placement of a LVAD as a bridge to cardiac transplantation. A Jarvik 2000 Flowmaker (Jarvik Heart Inc) was implanted as part of a Food and Drug Administration investigational trial. This trial was approved by our institutional review board and informed consent was obtained from the patient. General anesthesia was instituted. Milrinone infusion was maintained and supplemented by dobutamine. Transesophageal echocardiography confirmed a competent aortic valve and absence of flow across the intra-atrial septum. The left ventricle was markedly dilated with severe dysfunction (end-diastolic diameter, 97 mm). The right ventricle (RV) was also severely dilated and dysfunctional. Tricuspid regurgitation was moderate. A median sternotomy was performed and the pericardium was opened to reveal a gigantic heart. The patient was heparinized and was also cannulated in case of an emergent need for CPB. The left pleural cavity was widely opened. No pericardial retraction sutures were applied. Using a chest tube to simulate the proposed path of the LVAD conduit, we measured the length from the left ventricle apex to the ascending aorta coursing through the left hemithorax. Routing through the left hemithorax allows a more natural lie, reducing the likelihood of kinking. The driveline was exteriorized through the right upper abdominal wall. The outflow graft was trimmed to the pre-identified length and placed inside a 20-mm ringed Gore-Tex vascular graft (W. L. Gore and Assoc, Flagstaff, AZ) trimmed to a similar length. This reinforced outer graft prevents kinking and offers protection during sternal re-entry. Care was taken to ensure there was no twisting of the outflow graft within the Gore-Tex tube (W. L. Gore & Assoc). A side-biting clamp was applied to the left side of the ascending aorta and a 15-mm arteriotomy was made. The graft was beveled and oriented such that the heel lay cephalad and slightly to the left. We ensured there was no rotation from the ventricular apex to insertion. The outflow graft was then anastomosed to the aorta using continuous 4-0 polypropelene. The graft was clamped and the side-biting clamp removed. The patient was placed in a steep Trendelenberg position with slight rotation to the right. A suction device (Guidant XPOSE [Boston Scientific, Natick, MA]) was then deployed on the right ventricular apex, just lateral to the anterior descending artery, and was used to gradually retract the left ventricle apex into the surgical field, as described by Piacentino and colleagues [4Piacentino 3rd, V. Jones J. Fisher C.A. et al.Off-pump technique for insertion of a HeartMate Vented Electric left ventricular assist device.J Thorac Cardiovasc Surg. 2004; 127: 262-264Abstract Full Text Full Text PDF PubMed Scopus (4) Google Scholar] for off-pump insertion of the Heartmate XVE (Thoratec Corp). Arterial pressures were maintained with a vasopressin infusion and occasional catecholamine boluses. Overall, cardiac displacement was well tolerated. A circle was marked on the left ventricle apex to outline the circumference of the sewing ring. Ten interrupted plegeted 2-0 Ethibond (Ethicon Inc, Somerville, NJ) mattress sutures were placed through the left ventricle myocardium and subsequently through the sewing ring (Fig 1A). Irritation of the myocardium triggered brief runs of ventricular tachycardia, which were suppressed by administration of magnesium, lidocaine, and amiodarone. The sutures were tied to secure the sewing ring. The outflow clamp was released slightly to remove the air from the graft and the sewing ring was stabilized with four hemostats (Fig 1B). A cruciate incision was made in the apex, which was then immediately cored using the coring knife. As the surgeon removed the coring knife, the assistant simultaneously inserted the Jarvik pump into the ventricle. The pump was secured, the air was removed, and support was initiated (Fig 1C). The suction device was disengaged and the heart was released back into the left pleural cavity, heparin was reversed, and the chest was closed. The patient made an uncomplicated recovery and was discharged from the intensive care unit in 2 days, and from the hospital in 3 weeks. A postoperative computed tomographic scan showed a satisfactory position of the device (Fig 2).Fig 2Computed tomographic scan showing completed implantation. Routing the outflow graft through the left hemithorax reduces the likelihood of kinking within the pericardial cavity.View Large Image Figure ViewerDownload (PPT) Avoidance of CPB during LVAD placement has several theoretical advantages including reduction in bleeding and less multiorgan injury. Although CPB can be avoided by using a thoracotomy or subcostal incision [2Frazier O.H. Implantation of the Jarvik 2000 left ventricular assist device without the use of cardiopulmonary bypass.Ann Thorac Surg. 2003; 75: 1028-1030Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar, 3Frazier O.H. Gregoric I.D. Cohn W.E. Initial experience with non-thoracic, extraperitoneal, off-pump insertion of the Jarvik 2000 Heart in patients with previous median sternotomy.J Heart Lung Transplant. 2006; 25: 499-503Abstract Full Text Full Text PDF PubMed Scopus (44) Google Scholar], these approaches limit the surgeon’s ability to perform adjunctive procedures, and may have increased thromboembolism due to stasis in the ascending aorta [5Siegenthaler M.P. Martin J. Gutwald R. et al.Anterior approach to implant the Jarvik 2000 with retroauricular power supply.Ann Thorac Surg. 2005; 80: 745-747Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar]. Using a median sternotomy for off-pump device implantation offers the potential benefits of avoiding CPB, while maintaining surgical exposure and additionally allowing for the addition of adjunctive cardiac procedures if required. We have overcome the obstacles to off-pump LVAD placement through a sternotomy (ie, inaccessibility of apex and hemodynamic instability) by using a suction device and pharmacological management. Although routine off-pump insertion through a sternotomy is theoretically possible with other implantable devices [4Piacentino 3rd, V. Jones J. Fisher C.A. et al.Off-pump technique for insertion of a HeartMate Vented Electric left ventricular assist device.J Thorac Cardiovasc Surg. 2004; 127: 262-264Abstract Full Text Full Text PDF PubMed Scopus (4) Google Scholar], we believe the simplicity of the Jarvik implantation technique makes it particularly suited for this role. We have since used this technique successfully for implant of the Jarvik 2000 on a second patient. Further study is necessary to determine the applicability and benefits of this technique.