First Experience With the Synergy Micro‐Pump in Patients in INTERMACS Class 1–2 as a Bridge to Transplantation: Pushing the Limits?

Abstract

The Synergy Micro-pump is the smallest implantable left ventricular assist device (LVAD) and provides partial flow support up to 4.25 L/min. It was shown that early intervention with this device can provide substantial benefits to patients with severe heart failure not yet sick enough for a full-support LVAD. However, as it can be inserted via small incisions with no need for sternotomy or cardiopulmonary bypass, it might be beneficial for selected high-risk patients. The aim of this study was to evaluate the efficacy of the Synergy Micro-pump in patients in INTERMACS class 1-2. From February 2012 to August 2013, 13 patients with severe heart failure were supported with the Synergy Pocket Micro-pump. Patients were divided into two groups according to INTERMACS class: the high-risk group (INTERMACS class 1-2) and the low-risk group (INTERMACS class 3-4). There were seven patients in INTERMACS class 1-2 and six in INTERMACS class 3-4. Patient demographics, perioperative characteristics, and postoperative outcomes were compared. There were no statistically significant differences in patient demographics, and mean support time was 108 ± 114 days in the high-risk group and 238 ± 198 days in the low-risk group. Also, there were no significant differences in perioperative characteristics or in the rate of postoperative adverse events. The overall survival was comparable between the two groups (one late death in each group, log-rank P = 0.608). Two patients from the high-risk group were upgraded to a full-support LVAD (P = 0.462) after 65 ± 84.9 days of mean support. One patient from the high-risk group and two patients from the low-risk group were successfully transplanted (P = 0.559). The use of the Synergy Micro-pump in INTERMACS 1-2 patients is feasible and is associated with similar postoperative outcome as in patients in INTERMACS 3-4. Carefully selected patients with severe heart failure could benefit due to the small size of the pump; however, further studies and medium-term follow-up are required.

Does CircuLite Synergy assist device as partial ventricular support have a place in modern management of advanced heart failure?

“…Nevertheless, it could be that concerns about development of right heart failure will be less with a partial-support device. This statement can also be supported by the fact that utilization of CircuLite was not reported to be associated with right-heart failure even in highrisk patients [22].…”

“…Surgical implantation technique is widely described [8,9,22]. Briefly, right subclavian artery is dissected through a 4-cm subclavicular incision and a small subcutaneous pocket is created inferior to the subclavian artery and in front of the right pectoralis major muscle for pump placement.…”

“…Also, aspirin and clopidogrel, 75 mg daily, is immediately started after extubation. Once chest drain are removed and patient could tolerate oral medication, warfarin is administered to maintain the international normalized ratio (INR) between 2.5 and 3.5 [22]. Heparin infusion is continued until the target INR range is attained.…”

“…A recent report addressed the feasibility of implementation of long-term partial circulatory support as a bridge to transplantation in high risk patients (INTERMACS class 1-2). It suggested that the system might be clinically efficacious even in high-risk patients who can benefit from a less invasive approach with lower risk of postoperative complications as well as from a significantly lower risk of heart transplantation with no need for re-sternotomy and extended dissection [22]. In general, the outcomes were comparable to less sick patients; however, there might be a higher risk for an upgrade to a full-support device due to a possible deterioration in hemodynamics and clinical condition.…”

Artificial Organs 2015: A Year in Review

“…Anton Sabashnikov et al of the Royal Brompton & Harefield NHS Foundation Trust, Harefield, UK reported on the Synergy Micro‐Pump in patients in INTERMACS class 1–2 as a bridge to transplantation. Thirteen patients were divided into two groups according to INTERMACS class: the high–risk group (INTERMACS class 1–2; 7 patients) and the low‐risk group (INTERMACS class 3–4; 6 patients).…”