Cardiac surgeries may expose pulmonary arterial tissue to systemic conditions, potentially resulting in failure of that tissue. our goal was to quantitatively assess pulmonary artery adaptation due to changes in mechanical environment. In 17 sheep, we placed a pulmonary autograft in aortic position, with or without macroporous mesh reinforcement. It was exposed to systemic conditions for 6 months. All sheep underwent 3 ECG-gated MRI's. Explanted tissue was subjected to mechanical and histological analysis. Results showed progressive dilatation of the unreinforced autograft, while reinforced autografts stabilized after two months. Some unreinforced pulmonary autograft samples displayed more aorta-like mechanical behavior with increased collagen deposition. the mechanical behavior of reinforced autografts was dominated by the mesh. the decrease in media thickness and loss of vascular smooth muscle cells was more pronounced in reinforced than in unreinforced autografts. In conclusion, altering the mechanical environment of a pulmonary artery causes changes in its mechano-biological properties.

Background and objectivesIn personalised external aortic root support (PEARS), a custom-made, macroporous mesh is used to stabilise a dilated aortic root and prevent dissection, primarily in patients with genetically driven aortopathies. Data are needed on the safety and postoperative incidence of aortic events.MethodsWe present a multicentre cohort study evaluating the first 200 consecutive patients (median age 33 years) undergoing surgery with an intention to perform PEARS for aortic root dilatation in 23 centres between 2004 and 2019. Perioperative outcomes were collected prospectively while clinical follow-up was retrieved retrospectively. Median follow-up was 21.2 months.ResultsThe main indication was Marfan syndrome (73.5%) and the most frequent concomitant procedure was mitral valve repair (10%). An intervention for myocardial ischaemia or coronary injury was needed in 11 patients, 1 case resulting in perioperative death. No ascending aortic dissections were observed in 596 documented postoperative patient years. Late reoperation was performed in 3 patients for operator failure to achieve complete mesh coverage. Among patients with at least mild aortic regurgitation (AR) preoperatively, 68% had no or trivial AR at follow-up.ConclusionsThis study represents the clinical history of the first 200 patients to undergo PEARS. To date, aortic dissection has not been observed in the restrained part of the aorta, yet long-term follow-up is needed to confirm the potential of PEARS to prevent dissection. While operative mortality is low, the reported coronary complications reflect the learning curve of aortic root surgery in patients with connective tissue disease. PEARS may stabilise or reduce aortic regurgitation.

OBJECTIVES: Wrapping with various materials was an early treatment for aortic aneurysms. Wrapping with low-porosity vascular grafts has been associated with graft migration and vascular erosion. An alternative is to use a macroporous mesh (MPM) made of the same polymer (polyethylene terephalate). We compared the histological outcome 1 year after wrapping sheep aortas with low-porosity grafts versus MPM fabrics. METHODS:The 2 different fabrics were wrapped around the aorta of 3 sheep. After 1 year the aortas were excised. The 2 wrapped segments of aorta were compared with each other and control aorta. Histological examinations and measurements were made of the layers of the aortic wall in 36 prespecified locations in each of the 3 sheep.RESULTS: Both fabrics were consistently surrounded by foreign body reaction and well-vascularized fibrosis. This was more pronounced with the low-porosity vascular graft material which was poorly incorporated and caused buckling at the transition between wrapped and unwrapped aorta. Conversely, the MPM was fully incorporated, resulting in a composite mesh/biological aortic wall. There was reduction of medial thickness with both materials but it was locally more extreme due to the corrugations in the vascular graft material. The findings were consistent between sampled locations and were similar in the 3 animals. CONCLUSIONS:The different porosity and rigidity of the materials influences their incorporation into the aortic wall. The incorporation of the pliable MPM precludes the complications of migration and erosion which are seen after wrapping with low-porosity prosthetic vascular graft material.

New antithrombotic drugs have been developed, new valve types have been designed and minimally invasive transcatheter techniques have emerged, making the choice of antithrombotic therapy after surgical or transcatheter heart valve repair and replacement increasingly complex. Moreover, due to a lack of large randomized controlled trials many recommendations for antithrombotic therapy are based on expert opinion, reflected by divergent recommendations in current guidelines. Therefore, decision-making in clinical practice regarding antithrombotic therapy for prosthetic heart valves is difficult, potentially resulting in sub-optimal patient treatment. This article compares the 2017 ESC/EACTS and 2020 ACC/AHA guidelines on the management of valvular heart disease and summarizes the available evidence. Finally, we established a convenient consensus on antithrombotic therapy after valve interventions based on over 800 annual cases of surgical and transcatheter heart valve repair and replacement and a multidisciplinary team discussion between the department of cardiovascular diseases and cardiac surgery of the University Hospitals Leuven, Belgium.

ObjectivesDifferences in indication and technique make a randomised comparison between valve-sparing root replacement (VSRR) and personalised external aortic root support (PEARS) challenging. We performed a propensity score (PS)-matched comparison of PEARS and VSRR for syndromic root aneurysm.MethodsPatients in the PEARS 200 Database and Aortic Valve Insufficiency and ascending aorta Aneurysm InternATiOnal Registry (undergoing VSRR) with connective tissue disease operated electively for root aneurysm <60 mm with aortic regurgitation (AR) <1/4 were included. Using a PS analysis, 80 patients in each cohort were matched. Survival, freedom from reintervention and from AR ≥2/4 were estimated using a Kaplan-Meier analysis.ResultsMedian follow-up was 25 and 55 months for 159 PEARS and 142 VSRR patients. Seven (4.4%) patients undergoing PEARS required an intervention for coronary injury or impingement, resulting in one death (0.6%). After VSRR, there were no early deaths, 10 (7%) reinterventions for bleeding and 1 coronary intervention. Survival for matched cohorts at 5 years was similar (PEARS 98% vs VSRR 99%, p=0.99). There was no difference in freedom from valve or ascending aortic/arch reintervention between matched groups. Freedom from AR ≥2/4 at 5 years in the matched cohorts was 97% for PEARS vs 92% for VSRR (p=0.55). There were no type A dissections.ConclusionsVSRR and PEARS offer favourable mid-term survival, freedom from reintervention and preservation of valve function. Both treatments deserve their place in the surgical repertoire, depending on a patient’s disease stage. This study is limited by its retrospective nature and different follow-ups in both cohorts.