The COORDINATE Pilot Study: Impact of a Transcatheter Aortic Valve Coordinator Program on Hospital and Patient Outcomes.

The transcatheter aortic valve implantation (TAVI) treatment pathway is complex, leading to procedure-related delays. Dedicated TAVI coordinators can improve pathway efficiency. COORDINATE was a pilot observational prospective registry at three German centers that enrolled consecutive elective patients with severe aortic stenosis undergoing TAVI to investigate the impact a TAVI coordinator program. Pathway parameters and clinical outcomes were assessed before (control group) and after TAVI coordinator program implementation (intervention phase). The number of repeated diagnostics remained unchanged after implementation. Patients with separate hospitalizations for screening and TAVI had long delays, which increased after implementation (65 days pre- vs. 103 days post-implementation); hospitalizations combining these were more efficient. The mean time between TAVI and hospital discharge remained constant. Nurse (p = 0.001) and medical technician (p = 0.008) working hours decreased. Patient satisfaction increased, and more consistent/intensive contact between patients and staff was reported. TAVI coordinators provided more post-TAVI support, including discharge management. No adverse effects on post-procedure or 30-day outcomes were seen. This pilot suggests that TAVI coordinator programs may improve aspects of the TAVI pathway, including post-TAVI care and patient satisfaction, without compromising safety. These findings will be further investigated in the BENCHMARK registry.

Transcatheter valve-in-valve implantation versus surgical redo aortic root replacement in patients with degenerated freestyle aortic bioprosthesis.

BACKGROUND: Transcatheter aortic valve-in-valve implantation (ViV TAVI) represents a new treatment option for patients with degenerated aortic bioprosthesis. Comparative data to redo surgical aortic valve replacement (redo SAVR) are limited. OBJECTIVE: We investigated feasibility and outcome of ViV TAVI versus redo SAVR in patients with symptomatic degenerated Medtronic Freestyle aortic bioprosthesis (FSB). METHODS: Between January 2002 and February 2020, 25 patients with failed FSB underwent ViV TAVI and 10 patients with failed FSB underwent redo SAVR. Endpoints were defined according to the Valve Academic Research Consortium-2 (VARC-2) criteria. RESULTS: Age and logistic EuroSCORE II were higher in patients with ViV TAVI (75.4 ± 1.7 vs. 62.9 ± 5.1 years, p = .019; 11.5 ± 1.6 vs. 5.6 ± 5.6%, p = .007). Valve implantation was successful in all cases. Mean transvalvular pressure gradients were significantly lower in patients with redo SAVR than ViV TAVI (7.6 ± 1.0 vs. 10.3 ± 0.8 mmHg, p = .037). Aortic valve regurgitation was absent in 91% and 100% of patients with ViV TAVI and redo SAVR, respectively. Thirty-day mortality rates were 12% in the ViV TAVI cohort versus 0% in the redo SAVR cohort (p = .542). Within the first year after hospital discharge, one patient after ViV TAVI had redo surgical intervention. CONCLUSIONS: ViV TAVI and redo SAVR lead to excellent functional results in patients with degenerated FSB. Post-procedural early complications must be considered particularly in patients with ViV TAVI because of higher clinical risk profiles.

Topical mitogen-activated protein kinases inhibition reduces intimal hyperplasia in arterialized vein grafts.

OBJECTIVE: Vein graft arterialization results in activation of the mitogen-activated protein kinases (MAPKs) extracellular signal-regulated kinases-1 and -2 (ERK1/2), which have been implicated in cell proliferation, migration, and apoptosis. The goal of our study was to characterize the effect of MAPK inhibition on intimal hyperplasia (IH) in arterialized vein grafts in hypercholesterolemic rabbits. METHODS: Reversed bilateral jugular vein to common carotid artery interposition grafts were constructed in 16 New Zealand White rabbits. The veins were incubated for 30 min prior to grafting with either the synthetic ERK1/2 activation inhibitor UO126 or the control vehicle. Vein graft and control jugular vein were harvested 3 h, 1 d, and 28 d after arterialization for histological and biochemical analyses. RESULTS: Treatment with UO126 was associated with 31% reduction in mean intimal area (1.68 +/- 0.78 mm(2)versus 2.44 +/- 1.65 mm(2); mean +/- SD; P = 0.036) relative to controls. The intima-to-media ratio of UO126-treated vein grafts decreased by 29% (0.53 +/- 0.04 versus 0.74 +/- 0.06; mean +/- SD; P < 0.01) compared to controls, vehicle-treated vein grafts. There was also significant increase in apoptosis in UO126-treated vein graft medial cell layer at 1 d. CONCLUSION: Topical administration of UO126 before vein grafting significantly decreases IH in arterialized vein grafts in hypercholesterolemic rabbits. These results may have significant implications for the development of strategies aimed at blocking or reducing IH in bypass grafts. Therefore, further evaluation of this simple strategy to improve vein graft patency following coronary artery or peripheral vascular bypass surgery is warranted.

Mechanisms of c-reactive protein up-regulation in arterialized vein grafts.

BACKGROUND: C-reactive protein (CRP), an acute phase reactant, is an independent predictor of coronary artery syndromes and a mediator of the vascular response to injury. CRP has been found in arterialized vein grafts and has been linked to atherogenesis; however, its involvement in vein graft early failure or intimal hyperplasia has not been assessed. This study was designed to investigate the mechanism(s) of CRP up-regulation in arterialized vein grafts. METHODS: Carotid artery bypass with arterialized jugular vein grafts (AVG) was performed in 18 dogs. AVG were harvested at 3, 8, and 24 hours and 4, 14, and 28 days, using the femoral vein obtained at the time of AVG harvest as a control. Serum CRP levels were characterized by enzyme-linked immunosorbent assay; AVG expression of CRP was studied by immunofluorescence, Western blotting, in situ hybridization, Northern blotting, and quantitative RT-PCR. RESULTS: CRP levels peaked at 24 hours in serum and AVG but remained at baseline in control veins. By double immunofluorescence, CRP was associated with the media and adventitia of AVG. However, Northern blotting analysis showed no CRP mRNA expression in AVG. Reverse transcriptase polymerase chain reaction analysis confirmed the lack of up-regulation of CRP in AVG. CONCLUSION: CRP levels are increased in AVG, peaking 24 hours after arterialization. However, no significant production of CRP was detected in AVG. Therefore, increased CRP levels within AVG appear to originate mostly from CRP diffusion from the systemic circulation. These results have significant implications for the development of strategies aimed at blocking CRP up-regulation in bypass grafts.

Anti-proliferative and anti-inflammatory effects of topical MAPK inhibition in arterialized vein grafts.

Vein graft failure following bypass surgery is a frequent and important clinical problem. The vascular injury caused by arterialization is responsible for vein graft intimal hyperplasia, a lesion generated by medial smooth muscle cell proliferation and migration into the intima, increased extracellular matrix deposition, and formation of a thick neointima. Development of the neointima into a typical atherosclerotic lesion and consequent stenosis ultimately result in vein graft failure. Endothelial damage, inflammation, and intracellular signaling through mitogen-activated protein kinases (MAPKs) have been implicated in the early stages of this process. We therefore investigated the effects of topical inhibition of ERK-1/2 MAPK activation on vascular cell proliferation and apoptosis, and on the inflammatory response in a canine model of vein graft arterialization. For this purpose, vein grafts were incubated with the MEK-1/2 inhibitor, UO126, ex vivo for 30 min before grafting. This treatment effectively abolished arterialization-induced ERK-1/2 activation, decreased medial cell proliferation, and increased apoptosis. UO126 treatment also inhibited the vein graft infiltration by myeloperoxidase-positive inflammatory cells that follows vein graft arterialization. Thus, topical ex vivo administration of MAPK inhibitors can provide a pharmacological tool to prevent or reduce the vascular cell responses that lead to vein graft intimal hyperplasia and graft failure.