Minimally invasive delivery of a novel direct epicardial assist device in a porcine heart failure model

• Published in: Innovations (Philadelphia, Pa.) Vol. 9; no. 1; p. 16
• Main Authors: McGarvey, Jeremy R, Shimaoka, Toru, Takebayashi, Satoshi, Aoki, Chikashi, Kondo, Norihiro, Takebe, Manabu, Zsido, 2nd, Gerald A, Jassar, Arminder, Gorman, 3rd, Joseph H, Pilla, James J, Gorman, Robert C
• Format: Journal Article
• Language: English
• Published: United States 01.01.2014
• Subjects: Animals; Disease Models, Animal; Feasibility Studies; Heart Failure - diagnosis; Heart Failure - physiopathology; Heart Failure - surgery; Heart-Assist Devices; Magnetic Resonance Imaging, Cine; Male; Pericardium; Prosthesis Design; Stroke Volume; Swine; Thoracoscopy - methods; Ventricular Function, Left
• ISSN: 1559-0879
• DOI: 10.1097/IMI.0000000000000049

Despite advances in design, modern ventricular assist device placement involves median sternotomy and cardiopulmonary bypass and is associated with infectious/embolic complications. In this study, we examine the feasibility and function of a novel minimally invasive, non-blood-contacting epicardial assist device in a porcine ischemic cardiomyopathy model. Feasibility was first tested in an ex vivo thoracoscopic trainer box with slaughterhouse hearts. Five male Yorkshire swine underwent selective ligation of the circumflex artery to create a posterolateral infarct Twelve weeks after infarct, all animals underwent left minithoracotomy. A custom inflatable bladder was positioned over the epicardial surface of the infarct and firmly secured to the surrounding border zone myocardium with polypropylene mesh and minimally invasive mesh tacks. An external gas pulsation system actively inflated and deflated the bladder in synchrony with the cardiac cycle. All animals then underwent cardiac magnetic resonance imaging to assess ventricular function. All subjects successfully underwent off-pump placement of the epicardial assist device via minithoracotomy. Ejection fraction significantly improved from 29.1% ± 4.8% to 39.6% ± 4.23% (P < 0.001) when compared with pretreatment. End-systolic volume decreased (76.6 ± 13.3 mL vs 62.4 ± 12.0 mL, P < 0.001) and stroke volume increased (28.6 ± 3.4 mL vs 37.9 ± 3.1 mL, P < 0.05) when assisted. No change was noted in end-diastolic volume (105.1 ± 11.4 vs 100.3 ± 12.7). On postmortem examination, mesh fixation and device position were excellent in all cases. No adverse events were encountered. Directed epicardial assistance improves ventricular function in a porcine ischemic cardiomyopathy model and may provide a safe alternative to currently available ventricular assist device therapies. Further, the technique used for device positioning and fixation suggests that an entirely thoracoscopic approach is possible.