Outflow graft obstruction in patients with the HM 3 LVAD: A percutaneous approach.

BACKGROUND: The use of the HeartMate 3 (HM3) left ventricular assist device (LVAD) is expanding. Despite being associated with lower rates of adverse events and increased survival, outflow graft obstruction (OGO) has been reported in patients with HM3. The incidence and best management of this serious complication remain unclear. METHODS: We describe six cases of HM3 OGO occurring in five patients in our institutional HM3 cohort. Four cases underwent computed tomography angiography and in two percutaneous angiography was directly performed to confirm the diagnosis. In four cases, percutaneous repair of the OG was performed using common interventional cardiology (IC) techniques. RESULTS: Our institutional incidence of OGO was 7% (event rate of 0.05 per patient year); much higher than the previously reported incidence of 1.6%. All cases occurred in the bend relief covered segment. Only two patients had apparent OG twisting, and in two, OGO occurred despite placement of an anti-twist clip at the time of implant. External compression seems to play a role in most cases. Balloon "graftoplasty" and stent deployment via the femoral artery alleviated the obstruction and normalized LVAD flow in all patients who underwent percutaneous repair. The use of self-expanding stents allowed for downsizing of the procedural access site to 10 Fr. No serious procedure-related complications occurred. CONCLUSION: OGO is common in HM3 patients, external compression due to biomaterial accumulated surrounding the OG is a common etiology. Percutaneous repair using standard IC techniques is safe and feasible in cases of compression with or without partial twisting.

Digoxin Is Associated With a Decreased Incidence of Angiodysplasia-Related Gastrointestinal Bleeding in Patients With Continuous-Flow Left Ventricular Assist Devices.

BACKGROUND: Gastrointestinal bleeding (GIB) is one of the principal adverse events affecting patients with continuous-flow left ventricular assist devices (CF-LVADs). Despite the early recognition that GIB is commonly because of gastrointestinal angiodysplasia (GIAD), the exact pathophysiology of this process remains elusive. It has been postulated that the abnormal hemodynamic profile in CF-LVAD patients may activate the angiogenesis signaling cascade via the HIF (hypoxia-inducible factor)-1α/angiopoietin-2 pathway leading to formation of GIADs. Digoxin is a potent inhibitor of HIF-1α synthesis, and we hypothesized that its use reduces the incidence of GIAD and GIB in patients with CF-LVAD. METHODS AND RESULTS: Charts of all adult patients implanted with CF-LVAD between February 2006 and February 2017 were reviewed with particular emphasis on occurrence and cause of GIB. Fifty-four of 199 patients (27%) experienced a GIB. Overall frequency of GIB was lower in the 64 patients receiving digoxin compared with the 135 patients not receiving digoxin (16% versus 33%, P=0.01). Multivariable-adjusted Cox regression analysis confirmed that digoxin use was independently associated with a reduced risk for overall GIB (hazard ratio, 0.49; 95% CI, 0.24-0.98; P=0.045). GIBs were then categorized as non-GIAD, GIAD, or likely GIAD. Although the incidence of non-GIAD was similar in both groups (11% versus 7%, P=0.41), the frequency of GIAD/likely GIAD bleeding was significantly reduced in the digoxin group (5% versus 25%, P=0.0003). Multivariable-adjusted analysis confirmed that digoxin use was independently associated with a reduced risk for GIAD/likely GIAD bleeding (hazard ratio, 0.18; 95% CI, 0.06-0.6; P=0.005). However, digoxin use was not associated with reduced risk for non-GIAD GIB (hazard ratio, 1.54; 95% CI, 0.58-4.08; P=0.39). CONCLUSIONS: Use of digoxin was associated with a significant reduction in GIAD-related GIB in patients with CF-LVAD.

Outcomes After Transplantation of Donor Hearts With Improving Left Ventricular Systolic Dysfunction.

BACKGROUND: Left ventricular systolic dysfunction (LVSD) accounts for almost 25% of nonacceptance of potential donor hearts. Previous smaller, single-center studies showed that LVSD following brain death may be transient, and such hearts can be successfully resuscitated with resolution of LVSD, then transplanted. OBJECTIVES: This study evaluated outcomes of donor hearts with LVSD on initial transthoracic echocardiogram (TTE) that resolved during donor management. METHODS: We reviewed echocardiograms of all cardiac donors in the United Network of Organ Sharing database that were transplanted from January 1, 2007, to September 30, 2015, and identified 472 donor hearts with LVSD (left ventricular ejection fraction [LVEF] ≤40%) on initial TTE that resolved (LVEF ≥50%) during donor management on a subsequent TTE. These patients comprised the improved donor LVEF group. These were compared with donor hearts with normal LVEF (LVEF ≥55%) on the initial TTE for recipient mortality, cardiac allograft vasculopathy (CAV), and primary graft failure (PGF). RESULTS: There was no significant difference in recipient mortality at 30 days, 1 year, 3 years, and 5 years of follow-up, nor any difference in rates of PGF at 90 days and CAV at 5 years between recipients of donor hearts with improved LVEF and recipients of donor hearts with initially normal LVEF. Post-transplant length of stay was also similar between the 2 groups. Using propensity scores, 461 transplants in the improved-donor LVEF group were matched to 461 transplants in the normal-donor LVEF group. There was no significant difference in PGF at 90 days or recipient mortality after up to 5 years of follow-up. CONCLUSIONS: In the largest analysis of donor hearts with transient LVSD, we found that such hearts can be successfully resuscitated and transplanted without increasing recipient mortality, CAV, or PGF. These results underscore the importance of appropriate donor management and should help to increase utilization of donor hearts with transient LVSD.

Watchful Waiting in Continuous-Flow Left Ventricular Assist Device Patients With Ongoing Hemolysis Is Associated With an Increased Risk for Cerebrovascular Accident or Death.

BACKGROUND: Management of hemolysis in the setting of suspected device thrombosis in continuous-flow left ventricular assist device patients varies widely, ranging from watchful waiting with intensified antithrombotic therapy to early surgical device exchange. The aim of this study was to compare the outcomes of hemolysis events treated with surgical interventions versus medical management alone. METHODS AND RESULTS: A retrospective review of Heartmate II continuous-flow left ventricular assist device patients at 2 centers from January 2009 to September 2014 was completed. Patients were categorized as surgical management if hemolysis refractory to intensification of standard antithrombotic therapy was treated surgically. The primary end point was the first occurrence of cerebrovascular accident (CVA) or death. Sixty-four hemolysis events occurred in 49/367 patients implanted with Heartmate II continuous-flow left ventricular assist devices. Of 49 primary hemolysis events, 24 were treated with surgical interventions. After surgical treatment, 1 patient died and 2 experienced CVAs, as compared with 3 deaths and 9 CVAs in the 25 patients who remained on intensified antithrombotic therapy alone. The 1-year freedom from CVA or death was 87.5% and 49.5% in the surgical and medical cohorts, respectively (P=0.027). Resolution of a primary hemolysis event without CVA or death occurred in 21/24 patients treated with surgical interventions and in 13/25 who remained on medical therapy alone. A similar association between treatment and outcome was noted in the 15 recurrent hemolysis events. CONCLUSIONS: Hemolysis refractory to intensification of antithrombotic therapy identifies continuous-flow left ventricular assist device patients at major risk for CVA and death. Early device exchange should be considered to minimize these risks.