Fully Endoscopic Mitral Valve Repair with Percutaneous Cannulation of Groin Vessels

Summary

This protocol demonstrates in detail how to perform fully endoscopic mitral valve surgery (EMS) with percutaneous cannulation of the groin vessels, using a percutaneous plug-based vascular closure device. Fundamental steps and useful instructions are described in detail for each step.

Abstract

Endoscopic mitral valve surgery (EMS) has become a standard of care at specialized heart centers, further reducing surgical trauma compared to a traditional minimally invasive, thoracotomy-based approach. Exposure of the groin vessels for the establishment of cardiopulmonary bypass (CPB) via surgical cutdown in minimally invasive surgery (MIS) may result in wound healing disorders or seroma formation. The avoidance of surgical exposure of the groin vessels by using fully percutaneous techniques for the insertion of a CPB cannula with the implementation of vascular pre-closure devices has the potential to reduce these complications and improve clinical results. Herein, we present the utilization of a novel plug based vacsular closure device with a resobable collagen plug and the absence of suture material for closure of the arterial access for CPB in MIS. While this device was initially predominantly used in transcatheter aortic valve implantation (TAVI) procedures, with its safety and feasibility shown, we herein show that it can be used in CPB cannulation, since it is capable of closing arterial access sites up to 25 French (Fr.) in size. This device may be suitable to significantly reduce groin complications in MIS and simplify the establishment of CPB. Here, we describe the fundamental steps of EMS, including percutaneous groin cannulation and decannulation using a vascular closure device.

Introduction

The gold standard for the treatment of primary, degenerative mitral regurgitation (MR) is surgical mitral valve (MV) repair. The efficacy of this approach has been proven in large clinical studies with conclusive long-term data¹. Due to a large armamentarium of surgical techniques for MV repair, such as annuloplasty or the insertion of Gore-Tex neochordae, almost all pathologies of the MV are treatable. This includes complex circumstances like Morbus Barlow with prolapse of both MV leaflets, with proven safety and efficacy as well as excellent results up to 20 years². Furthermore, the majority of isolated MV surgery in Germany is performed via minimally invasive approaches, like a right anterolateral minithoracotomy³. Also, concomitant tricuspid valve (TV) surgery is amenable by minimally invasive access, even in a beating heart fashion^4,5.

Surgical cutdown to access groin vessels has traditionally been a routine procedure for the implementation of cardiopulmonary bypass (CPB). However, this approach inherits a certain risk of postoperative wound healing disorders or seroma formation⁶. The adaption of transcatheter techniques for fully percutaneous insertion of a cannula for the establishment of CPB has been described^7,8, and this may reduce possible groin complications. Already used devices for percutaneous vessel closure in endoscopic mitral valve surgery (EMS) include suture-based systems^7,8. Recently, a collagen plug-based vascular closure device was introduced for transcatheter heart valve procedures. This large bore closure device can be used for the closure of arterial access sites of up to 25 French (Fr.). Safety and efficacy of the system have previously been demonstrated in a real-world transcatheter aortic valve implantation (TAVI) patient cohort⁹. The first data of minimally invasive surgery (MIS) of the MV or TV utilizing this system for the closure of the femoral artery showed promising results regarding postoperative groin complications¹⁰.

We herein describe the fundamental steps of fully endoscopic mitral valve surgery, including percutaneous groin cannulation and decannulation using a novel vascular closure device. The fully endoscopic approach differs from the MIS non-endoscopic technique in terms of a very small thoracic incision (3-5 cm), avoidance of rib-spreading, and visualization of cardiac structures with an endoscope with no direct view of the heart.

This surgery can be performed on patients with significant heart valve regurgitation or stenosis of atrioventricular heart valves, who are suitable for cardiac surgery. Preoperative diagnostics include transthoracic/transesophageal echocardiography and computed tomography of the chest and iliac vessels in elderly patients or patients with a history of peripheral artery disease.

Protocol

All herein-described procedural steps were performed in accordance with the Institutional Review Board of the University Heart and Vascular Center Hamburg guidelines and after written informed consent was obtained.

1. Fully endoscopic MIS MV repair

1. Ensure the patient is under general anesthesia, in a supine position, scrubbed with iodine disinfectant, and draped with a sterile drape.
2. Gain thoracic access along the peri-mammillary margin through the fourth intercostal space.
3. Achieve distension of the intercostal space using a soft-tissue retractor.

2. Percutaneous cannulation of groin vessels

1. Position two cannulas in the femoral artery and vein under transesophageal echocardiogram (TEE) guidance to establish CPB for MIS.
2. Perform puncture of the femoral artery using a standard puncture needle and insert a 0.035 mm guidewire under TEE guidance.
3. Determine the depth of the initial puncture using a puncture-locating dilator, which is inserted over the wire. This detects puncture depth by outlet backflow/the stop of backflow.
4. Define the depth at skin level, which is defined by the visible stop of backflow of the measuring tool.
   NOTE: For the later release of the vessel closure device, deployment depth is defined as the puncture depth at skin level plus 1 cm.
5. Place the arterial cannula (sizes vary according to body surface area) over the wire and connect it to CBP.
6. Puncture the femoral vein medial to the artery in the same manner (step 2.2) and after insertion of the venous cannula connects to the CBP.

3. MV repair

1. Insert the 3D-HD camera over the thoracic incision.
2. Open the pericardium above the right site phrenic nerve using diathermy.
3. Place a transthoracic Chitwood aortic clamp through a small incision for cross-clamping of the aorta under the induced ventricular fibrillation.
4. Arrest the heart with antegrade Del-Nido cardioplegia and moderate hypothermia of 32 °C, which is established and maintained by the heart and lung machine. The effectiveness of cardioplegia is documented by an electrocardiogram.
5. Open the left atrium with scissors and lift the left atrial roof with a dynamic retractor.
6. Expose the MV and inspect the pathology, by prolapse of the posterior mitral leaflet in this case.
7. Determine the size for the correct annuloplasty ring and neochordae via an annuloplasty measuring tool and a caliper for the length of native chordae.
8. Resuspend the posterior mitral leaflet (PML). Implant the annuloplasty ring by implanting the neochordae at the respective papillary muscle and placing circumferential annulus sutures.
9. Secure the neochordae to the papillary muscle, pass twice through the free margin of the posterior leaflet, and knot down.
10. Place circumferential sutures around the annulus and then put the sutures through the annuloplasty ring, which is taken down onto the annulus via the sutures.
11. Close the left atrium with a polypropylene, non-absorbable 4-0 suture; remove the aortic cross-clamp.
12. Close the thoracic access and perform CBP weaning.

4. Decannulation and vascular closure

1. Remove the venous cannula using a Z-suture technique at the cannula entrance site and tie down the suture after pulling out of the cannula.
2. For closure of the femoral artery, use the collagen plug-based closure device.
3. Clamp the arterial cannula, puncture the cannula, and insert a wire under TEE guidance.
4. Retract the cannula over the wire by holding the wire in place to ensure a safe wire position in the descending aorta.
5. Insert the closure system sheath fully over the wire and remove the dilator.
6. Insert the closure device over the integrated insertion tool and slowly remove the whole system at a steady 45° angle under constant retraction force to the measured depth.
7. Observe markings on the sheath, adjust the deployment depth, and rotate the lever for toggle release.
8. Retract the system further from the femoral artery until tension appears and the indicator field appears yellow/green.
9. Advance the lock advancement tool until a click is heard; the puncture is now sealed via an extravascular collagen plug.
10. When hemostasis is obtained, remove the guide wire, cut the lead suture, and close the skin with a single suture.
11. Apply a pressure bandage for 6 h.
    NOTE: This is the end of the surgery.

Results

In a preliminary patient cohort undergoing EMS and using this novel vascular closure device at our center, promising results were documented¹¹. This cohort included 35 patients, with the most common accompanying diseases being arterial hypertension (10/35, 28.6%) and atrial fibrillation (9/35, 25.7%). Valve failure mechanisms included primary, degenerative MR (30/35, 85.7%), secondary, functional MR (3/35, 8.6%), and endocarditis (2/35, 5.7%). Concomitant procedures in MV MIS MV were tricuspid val...

Discussion

The application of vascular closure devices for arterial CPB cannulation is a transcatheter technique that has the potential to improve outcomes in cardiac surgery is. Application of this technique in cardiac surgery procedures, and especially EMS valve surgery, has been adopted in specialized centers over recent years to avoid surgical cutdown and the exposure of groin vessels. ProStar and ProGlide systems are the most commonly used devices^7,12. In a series of 3...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
30° camera head	Aesculap Einstein Vision	PV 632
3D-HD camera	Aesculap Einstein Vision	PV 630
Annuloplasty ring	Edwards	93381
Aortic clamp	Cardio Vision	CV 195.10
Aterial Cannula	Medtronic	96570-121
Femoral Cannula	Metronic	96670-125
Full HD 3D Monitor	Aesculap Einstein Vision	PV 646
Giude wire	Merit Medica	6678-71
Heart valve retractor set	Cardio Vision	CV 100.00
LED light source	Aesculap Einstein Vision	OP 950
Manta	Teleflex Medical Inc.	2115
Neo chordae	Serag Wiesner	MCL14A
Soft Tissue Retractor	Cardio Vision	Cv100/80
Stative table arm for endoscopes	Cardio Vision	CV 281.73
Stative table arm for instruments	Cardio Vision	CV 281.72
Suture for fixing Loops	Gore-Tex Suture	4N02