Outflow Graft Narrowing of the HeartMate 3 Left Ventricular Assist Device

Extrinsic outflow graft flow obstruction in patients with HeartMate3 LVAD

“…The type of OGO observed in the reported series of five HeartMate3 LVAD patients (out of the 41 implanted with this type of LVAD since 2016 at our institution, 12%) has peculiar common features 2–5,7,8 : critical narrowing of the proximal outflow graft conditioning flow obstruction with no endoluminal thrombosis was documented (IVUS was in this sense diagnostic, Figure 1); hemolysis was absent, no progressive decline in LVAD blood flow was observed as in other types of OGO 1 . Resolution of flow obstruction with endovascular treatment resulted in recovery from heart failure and home discharge in three of four symptomatic patients.…”

“…Pump failure due to OGO is the worst adverse event for its subtle expression and critical presentation on top on the difficulties in approaching the obstruction point. Although OGOs have been extensively reported for all types of LVADs, a similar pattern of outflow graft alterations conditioning flow obstruction has been reported only recently from preliminary experiences limited to the HeartMate3 LVAD 2–5,7,8 . Compared with existing reports, 8 our work attempted to present the clinical emerging problem of OGO in a 360° approach: patients were indeed extensively characterized in terms of clinical presentation, hemodynamic data, relevant laboratory parameters, and longer follow‐up.…”

“…Although OGOs have been extensively reported for all types of LVADs, a similar pattern of outflow graft alterations conditioning flow obstruction has been reported only recently from preliminary experiences limited to the HeartMate3 LVAD. [2][3][4][5]7,8 Compared with existing reports, 8 our work attempted to present the clinical emerging problem of OGO in a 360° approach: patients were indeed extensively characterized in terms of clinical presentation, hemodynamic data, relevant laboratory parameters, and longer follow-up. Furthermore, diagnostic and treatment steps are presented for each patient in order to provide the most relevant information for the clinical management of this complication.…”

“…1 However, pump flow obstructions still represent very dangerous events that warrant timely diagnosis and treatment. In particular, outflow graft obstructions (OGO) is challenging as a consequence of endoluminal thrombosis, kinking, twisting, dissection, ab-extrinseco compression, [2][3][4][5][6] and a potential role of the graft material itself in OGO determination has also been identified. 7 We present a series of five destination therapy (DT) patients supported with HeartMate3 LVAD (Abbott Labs, Chicago, IL) that developed an extrinsic OGO after 607-1250 days of support, during prolonged antithrombotic regimen.…”

Recurrent outflow graft compression of HeartMate3: When the left ventricular assist device sticks to the rib

“… 1 However, extrinsic compression of the outflow graft due to biodebris accumulation between the graft and the external polytetrafluoroethylene tube, either intrinsic to the pump such as the outflow bend relief or externally applied to guard against kinking and re-exploration injury, is now recognized as a predominant HM3 complication with a reported incidence of up to 30%. 2 , 3 , 4 The outflow graft is constructed of a knitted polyethylene terephthalate material that has inherent porosity, permitting seepage of blood components that are trapped in-between the graft and bend relief. The gradual enlargement of this biodebris eventually leads to graft compression and symptoms related to low blood flow and/or congestion.…”