Bend relief fenestration might prevent outflow graft obstruction in patients with left ventricular assist device

OBJECTIVES: Patients with left ventricular assist devices may experience external obstruction of the outflow graft through a gelatinous substance within the bend relief (BR; a stiff tube graft guiding the outflow graft). Preventative strategies have been missing. Having faced this problem, we decided to fenestrate the BR to avoid outflow graft obstruction (OGO). METHODS: Since December 2010, 167 patients underwent left ventricular assist device implantation using HeartMate II or 3. BR fenestration was introduced on July 2018 (108 patients before, 59 after the introduction of BR fenestration). Follow-up computed tomography scans were obtained from all patients and were screened for OGO by 3 independent investigators. Results were correlated with log file history, echocardiographic and clinical outcomes. RESULTS: Demographic data were comparable between groups, with mostly male patients. Patients with BR fenestration were older [63 (standard deviation (SD):10.6) vs 58 (SD: 10.7) years] and had shorter support duration [494 (SD: 383) vs 951 (SD: 875) days]. OGO was observed in 5 patients and occurred only in patients without fenestration. Importantly, it occurred late on postoperative Days 412, 462, 1043, 1184 and 1506. Three patients are still asymptomatic. Surgical revision was required in the other 2 patients for pump thrombosis or continuous low flow. One of them died 36 days after revision due to right heart failure. CONCLUSIONS: Our results suggest that fenestration of the BR may be a preventative strategy to avoid external OGO. OGO occurred late, which suggests a careful long-term follow-up.