The increasing number of patients with end-stage heart failure in our setting, coupled with a progressive reduction in organ donors, has created a need for alternative therapeutic options to sustain and extend life expectancy in these patients. Continuous-flow ventricular assist devices (CF-VADs) therapy is recommended for selected patients with end-stage heart failure, serving as a bridge to transplant, bridge to candidacy, or destination therapy.

In our country, CF-VAD programs have primarily been concentrated in tertiary centers affiliated with cardiac transplant programs. As destination therapy becomes more common—often due to a lack of compatible donors or failure to achieve transplant candidacy—some secondary centers (without cardiac transplant programs) have incorporated these device implants into their therapeutic arsenal for patients ineligible for referral to a tertiary center.

Several studies indicate that implantation outcomes are related to the annual volume of each center. Although optimal activity volume thresholds remain controversial, some authors suggest an ideal range of 20 to 50 annual implants per center. Medicare® and Medicaid® programs require surgeons to perform at least 10 procedures, prioritizing individual experience over total center volume. Nevertheless, optimal results combine appropriate patient selection, surgical procedure, postoperative care, and long-term medical follow-up.

The study includes data from a Canadian center with 51 consecutive patients who underwent HeartMate II® implantation between January 2009 and December 2017. The results of two time series, early (2009-2014; n=25) and late (2015-2017; n=26), were compared. The median follow-up time was 51 months. Early-era patients had higher rates of diabetes, prior stroke, and inotropic support before HeartMate II® implantation. The 90-day mortality rate was not significantly higher in the early era (24% vs. 15%, p=0.43). However, the incidence of the composite outcome—isolated mortality, new stroke, reoperation for bleeding, need for temporary right ventricular mechanical support, and pump thrombosis at 90 days—was significantly higher in the early era (76% vs. 42%, p=0.01). The need for temporary right ventricular support and bleeding complications were major contributors to the composite outcome, reflecting limited team experience. Cumulative survival (CUSUM) analysis established a threshold of 23 operations after which composite outcome results optimized.

The authors concluded that low-volume centers could achieve good outcomes in HeartMate II® implantation with an acceptable learning curve. Significant changes in patient selection, surgical techniques, and patient management could lead to improved outcomes after CF-VAD implantation.

COMMENTARY:

The experience of this Canadian team is both pioneering and courageous. It provides evidence on the potential success of establishing a mechanical ventricular assist program outside major transplant centers. Similarly to other advanced heart failure therapies (resynchronization therapy, mitral clip…), now available in secondary-level centers with only the requirement of cardiac surgery capabilities on site, coordinated liberalization of these programs with the transplant reference center could extend and enhance the care network for end-stage heart failure patients, avoiding the bottleneck effect fostered by a centralized system. This notion is reinforced by the recent publication of the “Code Shock” consensus document, which seeks to structure short-term mechanical circulatory support for patients experiencing decompensation. Following stabilization, some may become candidates for these devices. Thus, multidisciplinary collaboration, even across institutional borders, effective communication beyond fax, email, and phone, and a responsible approach to device indication and associated healthcare costs can open a new care paradigm better aligned with the needs of our population.

REFERENCE:

Hébert M, Noly PE, Lamarche Y, Dagher O, Bouhout I, Hage-Moussa E, Lévesque T, Giraldeau G, Racine N, Ducharme A, Carrier M. Learning curve in left ventricular assist device implantation: low volumes do not equate bad outcomes. Braz J Cardiovasc Surg. 2022 Oct 8;37(5):628-638. doi:10.21470/1678-9741-2021-0498.

Martínez Selles M, Hernández Pérez FJ, Uribarri A, Martín Villén L, Zapata L, Alonso JJ, et al. Código sock cardiogénico 2023. Documento de expertos para la organización multidisciplinaria que permita una atención de calidad. Rev Esp Cardiol. 2022. doi:10.1016/j.recesp.2022.10.010.