Minimally invasive techniques for heart valve procedures
Authors: Kastengren Mikael 
Published: January 2025

<p dir="ltr"><b>Background</b></p><p dir="ltr">Minimally invasive cardiac surgery (MICS) has emerged as an alternative to conventional sternotomy, offering potential benefits due to reduced surgical trauma. This thesis evaluates the clinical outcomes, safety, and efficacy of MIMVS and the use of percutaneous femoral access and plug-based VCD in MIMVS and transcatheter aortic valve replacement (TAVR).</p><p dir="ltr"><b>Methods and Results</b></p><p dir="ltr"><i>Study I</i>: This single-center study analyzed patients who underwent mitral valve surgery at Karolinska University Hospital between January 2012 and May 2019, treated either via sternotomy or MIMVS. A total of 605 patients (294 sternotomy, 311 minimally invasive) were included. Propensity score matching was performed, resulting in 251 matched pairs. In the matched analysis, minimally invasive procedures had a shorter aortic occlusion duration (97+36 vs. 105+40 min; p=0.03) but a longer extracorporeal circulation duration (149+52 vs. 133+57 min; p=0.001). Minimally invasive procedures were associated with a lower incidence of reoperation for bleeding (2.4% vs. 7.2%; p=0.012), reduced need for transfusion (19.1% vs. 30.7%; p=0.003), and a shorter in-hospital stay (5.0+2.7 vs. 7.2+4.6 days; p<0.001).</p><p dir="ltr"><i>Study II</i>: This single-center prospective study compared patients undergoing MIMVS with femoral cannulation, performed either via surgical cut-down or percutaneously with access site closure using a plug-based VCD (MANTA, Teleflex/Essential Medical Inc., Malvern, Pennsylvania, USA) between 2016 and 2018. A total of 268 patients (147 surgical cut-down, 121 percutaneous) were included, with 109 matched pairs after propensity score matching. The primary outcome was vascular complications according to Valve Academic Research Consortium (VARC)-2 criteria. The VCD group had a significantly higher rate of major vascular complications (4.6% vs. 0%; p=0.024). No bleeding occurred in either group. In the full series, patients in the surgical cut-down group had a significantly higher incidence of seroma (10.9% vs. 0%, p<0.001). Infection and seroma were not observed in the VCD group.</p><p dir="ltr"><i>Study III</i>: A single-center observational study evaluated 1000 consecutive patients undergoing transfemoral TAVR between May 2017 and September 2020. Patients received a MANTA VCD for arterial access management, and outcomes were assessed using VARC-2 criteria. The primary endpoint was VCD- related major vascular complications. Major vascular complications occurred in 4.2% of patients. Complications included the need for a covered stent (1.7%), surgical repair (1.7%), and vascular surgery post-discharge (0.3%). A significant risk factor for vascular complications was a larger sheath outer diameter relative to the femoral artery's inner diameter (p=0.028).</p><p dir="ltr"><i>Study IV</i>: This single-center study included 650 patients undergoing MICS between August 2017 and September 2022. The early group (207 patients) did not undergo intraoperative ultrasound assessment after VCD placement, while the late group (443 patients) did. The primary outcome was vascular complications according to VARC-2 criteria. Six patients (2.9%) in the early group experienced vascular complications, while no complications were reported in the ultrasound-assessed group (p<0.001). A total of 15 patients (2.3%) required surgical cut-down due to incomplete hemostasis or femoral artery stenosis/occlusion, all caused by intravascular deployment of the closure device.</p><p dir="ltr"><b>Conclusions</b></p><p dir="ltr">[I] MIMVS was associated with comparable short-term outcomes to sternotomy mitral valve surgery. MIMVS had lower rates of bleeding, blood transfusions, and shorter hospital stays. The initiation of an MIMVS program, when managed appropriately, proved safe and effective. [II] The use of the MANTA VCD in MIMVS eliminated wound complications seen with surgical cut-down, such as seromas and infections, but was associated with a higher risk of major vascular complications. [IV] By introducing intraoperative ultrasound to assess proper positioning of the VCD, vascular complications were reduced, particularly femoral artery stenosis. [III] Also, the MANTA VCD was effective for large-bore arterial access management during transfemoral TAVR with a low rate of complications. A larger sheath-to-femoral artery diameter ratio increased the risk of complications. The studies confirm the safety and efficacy of the MANTA device in a broad patient population, although vascular risks must be carefully managed.</p><h3>List of scientific papers</h3><p dir="ltr">I. <b>Kastengren M,</b> Svenarud P, Källner G, Franco-Cereceda A, Liska J, Gran I, Dalén M. Minimally invasive versus sternotomy mitral valve surgery when initiating a minimally invasive programme. Eur J Cardiothorac Surg. 2020;58:1168-1174. <a href="https://doi.org/10.1093/ejcts/ezaa232" rel="noreferrer" target="_blank">https://doi.org/10.1093/ejcts/ezaa232</a></p><p dir="ltr">II. <b>Kastengren M,</b> Svenarud P, Källner G, Settergren M, Franco- Cereceda A, Dalén M. Percutaneous Vascular Closure Device in Minimally Invasive Mitral Valve Surgery. Ann Thorac Surg. 2020;110:85-91. <a href="https://doi.org/10.1016/j.athoracsur.2019.10.038" rel="noreferrer" target="_blank">https://doi.org/10.1016/j.athoracsur.2019.10.038</a></p><p dir="ltr">III. <b>Kastengren M,</b> Settergren M, Rück A, Feldt K, Saleh N, Linder R, Verouhis D, Meduri CU, Bager J, Dalén M. Percutaneous plug-based vascular closure device in 1000 consecutive transfemoral transcatheter aortic valve implantations. Int J Cardiol. 2022;359:7-13. <a href="https://doi.org/10.1016/j.ijcard.2022.04.033" rel="noreferrer" target="_blank">https://doi.org/10.1016/j.ijcard.2022.04.033</a></p><p dir="ltr">IV. Ma K, <b>Kastengren M,</b> Svenarud P, Green R, Dalen M. Routine use of percutaneous femoral cannulation in minimally invasive cardiac surgery. Eur J Cardiothorac Surg. 2023;63:ezad020. <a href="https://doi.org/10.1093/ejcts/ezad020" rel="noreferrer" target="_blank">https://doi.org/10.1093/ejcts/ezad020</a></p>