Clinical benefits of partial circulatory support in New York Heart Association Class IIIB and Early Class IV patients
Meyns, Bart × Simon, Andre Klotz, Stefan Wittwer, Thorsten Schlensak, Christian Rega, Filip Burkhoff, Daniel #
European Journal of Cardio-Thoracic Surgery vol:39 issue:5 pages:693-698
Objective: Full mechanical support with a left-ventricular assist device (LVAD) is generally limited to end-stage heart-failure patients. We have been studying the safety and efficacy of the partial support Synergy(®) Pocket Micro-pump as bridge-to-transplant in a less-sick group of patients as a prelude to a study of its use for destination therapy. Methods: The CircuLite(®) Synergy device is implanted via a small right-sided thoracotomy with an inflow cannula in the left atrium and an outflow graft connected to the right subclavian artery without the use of extracorporeal circulation. The micro-pump is the size of an AA battery, sits in the 'pacemaker' pocket subcutaneously in the right clavicular groove and pumps up to 3.0lmin(-1) from the left atrium to the right subclavian artery. Results: The device has been implanted in 27 patients awaiting cardiac transplant (22 males), age 54.8±10.0 years with ejection fraction (EF) 21±6%, mean arterial pressure 73.5±8.8mmHg, pulmonary capillary wedge pressure (PCWP) 27.5±7.8mmHg and cardiac index (CI) 2.0±0.4lmin(-1)m(-2). Duration of support has ranged from 6 to 281 days. Right-heart catheterization showed significant hemodynamic improvement in the short- and intermediate term after implant, with increases in CI from 2.0±0.4 to 2.8±0.6lmin(-1)m(-2) (p<0.001) and reductions in PCWP from 28±6 to 18±7mmHg (p=0.002) at an average of 9.5±5.5 weeks. Conclusions: The Synergy device provides partial hemodynamic support and its use is associated with significantly improved hemodynamics, thus appearing to interrupt and partially reverse the progressive hemodynamic deterioration typical of end-stage heart failure. Ongoing efforts are aimed at demonstrating additional clinical benefits and continuing to further improve the risk/benefit ratio.