Thrombocytopenia after sutureless and standard stented aortic valve replacement: a retrospective analysis of risk factors, clinical course, and early outcome.

OBJECTIVES: Thrombocytopenia following Perceval aortic valve replacement has been described previously with variable outcome. Studies have lacked a robust analysis of platelet fluctuation and factors affecting it. We aimed to statistically describe the trend in thrombocyte variability as compared with conventional aortic valve replacement, and to assess predictors as well as impact on associated outcomes. METHODS: One hundred consecutive patients with first-time Perceval were retrospectively compared to 219 patients after Perimount Magna Ease valve replacement. The primary outcome was the serial thrombocyte count on day 0-6. Generalized estimating equations were used to analyse the data using fixed-effect models: for the effect of the post-operative day on platelet count, and random-effect models estimating both time-variant (platelets) and time in-variant variables (valve type, age, LV function, pre-op platelet level). RESULTS: Perceval patients were older (72 ± 1 vs 68 ± 1 years, p < 0.01) with higher NYHA status (3(2-3) vs 2(1-2), p < 0.001). Mean platelet count in the sutureless group was lowest on day 2 (91.9 ± 31.6 vs 121.7 ± 53.8 × 103 µl-1), and lower on day 4 (97.9 ± 44) and 6 (110.6 ± 61) compared to the conventional group (157.2 ± 60 and 181.7 ± 79) but did not result in a higher number of transfusions, bleeding or longer hospital stay (p > 0.05). Reduced platelet count was a strong predictor of red cell transfusion in the conventional (p = 0.016), but not in the sutureless group (p = 0.457). Age (Coef -1.025, 95%CI-1.649--0.401, p < 0.001) and CPB-time (Coef 0.186, 95%CI-0.371--0.001, p = 0.048) were predictors for lower platelet levels. CONCLUSION: Considering the older patient profile treated with Perceval, postoperative thrombocytopenia does not impact on outcome in terms of transfusions, complications or hospital stay.

Perceval sutureless bioprosthesis versus Perimount sutured bioprosthesis for aortic valve replacement in patients with aortic stenosis: a retrospective, propensity-matched study.

BACKGROUND: Rapid-deployment aortic valve replacement (RDAVR) is an alternative to conventional AVR (cAVR) for aortic stenosis. Benefits include a reduction in operative times, facilitation of minimal access surgery and superior haemodynamics compared to conventional valves. However, further evidence is required to inform guidelines, preferably in the form of propensity-matched studies that include mid-term follow-up data. METHODS: This was a single-centre, retrospective, propensity-matched cohort study comparing the Perceval and conventional Perimount Magna Ease valve for short- and mid-term clinical parameters and size-matched mid-term echocardiographic parameters (n = 102 in both groups) from 2014 to 2020. Data were extracted from a nationally managed dataset. RESULTS: There were no demographic differences between the matched groups. The Perceval group had shorter cross-clamp time (Perceval 62 [49-81] minutes; Perimount 79 [63-102] minutes, P < 0.001), shorter bypass time (Perceval 89 [74-114] minutes; Perimount 104 [84-137] minutes, P < 0.001), and more frequent minimally-invasive approaches (Perceval 28%; Perimount 5%, P < 0.001). Size-matched haemodynamics showed initially higher gradients in the Perceval group, but haemodynamics equalised at 12 + months. The Perceval group had a more favourable % change in the left ventricular posterior wall dimension at 2 + years (Perceval - 4.8 ± 18; Perimount 17 ± 2). CONCLUSIONS: The Perceval facilitated shorter operations, which may benefit intermediate-high-risk, elderly patients with comorbidities requiring concomitant procedures. It also facilitated minimally invasive surgery. Size-matched haemodynamic performance was similar at mid-term follow-up, with the Perceval possibly better facilitating regression of left ventricular hypertrophy.

Basis, Process and Outcomes of a Student Involvement Project for Curriculum Review at the Imperial College School of Medicine.

Introduction: To help create a Bachelor of Medicine, Bachelor of Surgery (MBBS) curriculum centred around the student voice, the Imperial College School of Medicine (ICSM) recruited two medical students for a two-week student-staff collaboration in Summer 2019 for its wider curriculum review. This write-up discusses the background, processes, and outcomes of the collaboration and includes some student reflections. Methods: The team comprised a member of the faculty and two medical students (the authors). We met daily for two weeks and focussed on the Bioregulatory Systems (BRS) module of Year 1. There were three key areas of work: learning objectives, large-group sessions, and small-group sessions. Each aspect involved planning, implementation, and reflection. For example, learning objectives were recategorized and reorganised, students fed back on a new slide template for large-group sessions, and new small-group sessions were designed. Feedback from the staff was collected verbally, and the medical students submitted feedback in the form of a mid-project interview, a post-project report, and informally. Results: We achieved such outcomes as reorganising and refining learning objectives, improving large-group teaching sessions, and refining and creating small-group teaching sessions. Following the collaboration, we had a debrief session. Conclusions: This collaboration was highly valuable for both students and faculty; the feedback revealed that the ideas, discussions, and outputs had a substantial impact. Overall, student-staff collaboration will become increasingly valuable as we emerge from COVID-19; we hope this write-up informs and inspires more 'students as partners' projects worldwide.