Percutaneous Intervention in External Outflow Graft Obstruction of Magnetically Levitated Left Ventricular Assist Device: Long-Term Follow-Up and Quality of Life.

Abstract

Objectives: External compression of the outflow graft causing obstruction (eOGO) is a potentially lethal complication in patients on long-term mechanical circulatory support with the HeartMate 3 (HM3, Abbott) left ventricular assist device (LVAD). This complication results from the build-up of gelatinous substance between the bend relief and outflow graft and can be resolved by percutaneous intervention, surgery, or transplantation. This single-centre follow-up study evaluated the suitability of percutaneous intervention as a treatment strategy and long-term outcomes of eOGO patients in terms of laboratory, LVAD, and quality-of-life parameters.

Methods: On October 31, 2024, a search of the implantation centre's electronic database identified HM3 patients diagnosed with eOGO. Individual patient data concerning 31 cases was analyzed. A quality-of-life survey was conducted using the short version of the Kansas City Cardiomyopathy Questionnaire (KCCQ-12).

Results: The patient cohort had a median support time to eOGO diagnosis of 1219 days [976, 1917] and a post-treatment follow-up of 686 days [447, 1003]. 64.5% of patients (n = 20) underwent percutaneous intervention showing immediate LVAD flow improvement of 0.5 L/min post-intervention (p = 0.04). Of eight post-interventional survey respondents, 62.5% (n = 5) were assigned a fair-excellent health status according to the KCCQ-12.

Conclusions: Percutaneous intervention is a suitable treatment strategy for eOGO, resolving low flow and providing satisfactory long-term quality of life outcomes. Given the increasing eOGO incidence after 1 year of support and overall mortality of 29.0%, clinicians should remain on high alert for this complication. We suggest computed tomography (CT) imaging be considered early on when eOGO is suspected.