Sternal lifting technique for patients with sternal depression during robotic mitral repair

INTRODUCTION

Traditional surgical methods have been difficult for patients with chest wall deformities, but the use of the Electrical Sternum Lifting System (ESLS) has made the surgery easier.

MATERIALS AND SURGICAL TECHNIQUE

Patients with a sternum-to-vertebral distance of less than 80 mm on preoperative computed tomography (CT) scan routinely underwent sternal lift using the ESLS. The ESLS was effective in securing the operative field while suspending the sternum, allowing adequate observation of the left atrium, left ventricle, and the mitral valve, and safe mitral valve plasty. The use of the lifting device did not interfere with the robot arms, and the space between the sternum and vertebrae was widened with only a 3 mm wound to move the mitral valve surface in the sagittal plane, making the repair easy and accurate under robotic assistance. The effort to attach the ESLS was not difficult, and the postoperative cosmetic outcomes were excellent. Sixty-three out of 1002 patients (6.3%) underwent sternal elevation using ESLS. There were 19 males and 44 females with a mean age of 50.9 ± 14.0 years. The average of sternum-to-vertebral (S/V) distance was 72.4 ± 8.9 cm. Two patients had S/V distance of more than 80 mm but ESLS was used because of scoliosis.

Outcomes of Barlow mitral valve repaired by robot-assisted keyhole surgery

Objective

To present our strategy and the clinical outcomes of robot-assisted Barlow mitral valve keyhole surgery.

Methods

From May 2015 to March 2022, a total of 1281 patients underwent mitral valve repair at our institution, including 763 with robotics surgeries. Of these, 124 patients with Barlow mitral valve (49 ± 12 years, male/female ratio = 81:43) were treated using robotic assistance and included in this study.

Results

All operations were completed using 3 to 5 keyholes. Neochordae implantation using the loop technique was the first option, and resection was performed only in cases with an intrinsic risk of developing systolic anterior motion. Neochordae implantation was performed in 118 cases (95.1%) using 6.6 ± 3.0 neochordae. Posterior leaflet resection was performed in 27 (21.7%) patients. Operation time was 177 ± 42 minutes, cardiopulmonary bypass time was 127 ± 25 minutes, and aorta crossclamp time was 76 ± 16 minutes. Blood transfusion was required in 5 cases (4%). None of the patients required a conversion to valve replacement. The postoperative complications included bleeding (n = 4), stroke (n = 1), and infection (n = 2). Mitral valve regurgitation 1 week after repair was none or trivial in 122 cases (98.3%), mild in 2 cases (1.7%), and more than moderate in 0 cases. Freedom from reoperation was 99.2% during the follow-up period of 36 ± 21 months. One patient required reoperation due to infective endocarditis.

Conclusions

Robot-assisted keyhole surgery using the loop-first concept was adequate to help achieve satisfactory and safe perioperative outcomes for Barlow mitral valve.

Robotic Surgery for Triple Valve Insufficiency: A Case Report

A 63-year-old woman was referred to our institution for surgical treatment of triple valve (aortic, mitral, and tricuspid) insufficiency and underwent a robot-assisted endoscopic procedure. Three intercostal ports were placed in the right lateral chest for robotic instruments and a retrograde cardioplegic cannula, and a 5 cm thoracotomy was made for the procedure, which was a mitral valve repair with neochords and ring annuloplasty, an aortic valve replacement with bioprosthetic valve, and a ring tricuspid annuloplasty. Surgery was successfully achieved without blood transfusion or any complications.

Off-Pump Neochordae Implantation via Left Minithoracotomy for Recurrent Regurgitation Following Mitral Valve Repair: The First Case in Japan

Surgical fixation after recurrent regurgitation following surgical mitral repair has been technically demanding and associated with high morbidity and mortality. Avoiding reopening the adhesive site or limiting the usage of cardiopulmonary bypass are solutions for reducing the operative risk. We report a case of recurrent mitral regurgitation treated by off-pump neochordae implantation via left minithoracotomy. A 69-year-old woman with a history of conventional mitral repair via median sternotomy developed heart failure due to mitral regurgitation from recurrent posterior leaflet P2 prolapse. Four neochordaes were implanted off-pump via left minithoracotomy using a NeoChord DS1000 in the seventh intercostal space. No transfusion was required. The patient was discharged a week after the procedure with no complications. The regurgitation remains trivial 6 months after the NeoChord procedure.

Robot-Assisted Totally Endoscopic Mitral Valve Plasty and Coronary Artery Bypass Grafting

We experienced 3 cases of port-access robot-assisted totally endoscopic technique for mitral valve repair and concomitant coronary artery bypass. The right internal mammary artery was harvested, mitral valve was fixed, and the right internal mammary artery to right coronary artery anastomosis was carried out on the arrested heart. The use of cardiac arrest and a V-shaped hook technique facilitated the coronary anastomosis and the da Vinci Firefly test (Intuitive Surgical Inc., Sunnyvale, CA) could confirm patency of the graft.

A routine de-airing method for total endoscopic robot-assisted mitral valve repair

Intraoperative water testing is essential for assessing mitral valve morphology and degree of residual mitral regurgitation during mitral valve repair. However, in some cases, evacuating intracardiac air is challenging. Herein, we report the routine de-airing method during total endoscopic robot-assisted mitral valve repair at our institute and discuss its effectiveness. In brief, our de-airing methods involve the following steps: after restricting the blood flow of the cardiopulmonary bypass, intracardiac air was pushed out into the pulmonary veins by drawing blood from the right ventricle. The left atrium, left ventricle, and ascending aorta were filled with blood to remove air from the root cannula. Retrograde blood flow from the coronary sinus was used to remove air from the coronary arteries. At 10 min after cardiopulmonary bypass weaning, transesophageal echocardiography revealed that residual intracardial air was absent in 99% of patients in all three chambers (ascending aorta, left atrium, and left ventricle).

Robotic mitral valve plasty for isolated clefts of mitral valve leaflets

A 21-year-old female patient referred to our institute had been suffering from severe mitral valve regurgitation due to a rare anomaly: a typical cleft at the posterior mitral leaflet and the other partial one at the anterior leaflet. We successfully fixed the mitral valve using the robot-assisted totally endoscopic technique which could perform suture closure of both leaflets and annuloplasty. This communication is the first report of the robotic and totally endoscopic procedure which could treat this rare mitral anomaly.

Bilateral endoscopic technique for left atrial appendectomy and robot-assisted mitral valve repair

We report a bilateral thoracoscopic technique in which robot-assisted mitral valve repair was achieved concomitantly with stapler division of the large left atrial appendage. The patient was a 65-year-old male with severe mitral regurgitation, paroxysmal atrial fibrillation and a large-sized atrial appendage. Closure of the appendage was completed off-pump using a left thoracoscopic stapler-division technique previous to right thoracoscopic robot-assisted mitral valve repair and cryoablation. Complete closure of the appendage was confirmed in thoracoscopic views. The bilateral thoracoscopic technique could be preferable for the minimally invasive treatment of mitral valvular disease and concomitant large-sized atrial appendage management.

Novel Brain Protection Method for Zone 0 Endovascular Aortic Repair with Selective Cerebral Perfusion

Objective: Zone 0 thoracic endovascular aortic repair (TEVAR) is associated with a high incidence of cerebral infarction mostly due to the embolic shower of a plaque from the aortic arch when the stent graft brushes against the aortic wall. Thus, it is important to develop a method for protecting the brain from such embolism. We report the outcomes of Zone 0 TEVAR with a novel brain protection method using selective cerebral perfusion under extracorporeal membrane oxygenation (ECMO).

Materials and Methods: Two T-shaped grafts with ringed expanded polytetrafluoroethylene (ePTFE) were created using an 8-mm-ringed ePTFE anastomosed end-to-side with a 7-mm-ringed ePTFE. Carotid–carotid bypass and axillo-axillary bypass were established using these grafts. ECMO was connected to the grafts and the femoral vein. Bilateral carotid and axillary arteries were blocked, and cerebral perfusion was selectively maintained using ECMO. Total endovascular Zone 0 TEVAR was performed. The patency of brachiocephalic artery was maintained using the chimney or in situ fenestration technique.

Results: Since August 2016, seven patients with aortic arch aneurysms underwent the procedure. The mortality rate was 0%. No neurological complications developed.

Conclusion: This brain protection method using selective cerebral perfusion under ECMO is a safe method for Zone 0 TEVAR.

Combined robot-assisted mitral valve plasty and Nuss procedure via small ports

Pectus excavatum (PE) can be associated with cardiac disorders that also require surgical repair. Totally endoscopic robot-assisted mitral valve plasty for mitral valve regurgitation was performed while elevating the sternum with the aid of our original electrical sternum lifting system. Then, the Nuss procedure was performed successfully via small incision. Simultaneous robot-assisted cardiac surgery and the Nuss procedure is effective. Sternal elevation during cardiac surgery is very important for a safe procedure. The Nuss technique prevents perioperative cardiac compression and allows for correction of the pectus deformity with good cosmetic and functional results.

Successful Two-Stage Treatment for Coarctation of the Aorta-postductal Type and Aortic Regurgitation with Thoracic Endovascular Aortic Repair and Aortic Valve Replacement

We herein report a case of a 20-year-old man with aortic regurgitation (AR), coarctation of the aorta (CoA), and patent ductus arteriosus (PDA). The preoperative ankle–brachial pressure index was 0.56 in bilateral extremities. Enhanced computed tomography revealed CoA-postductal type. We decided to perform a two-stage surgery: thoracic endovascular aortic repair (TEVAR) for CoA and PDA and then open surgery for AR. TEVAR was successfully performed with deployment of the stent graft at a 31-mm diameter subsequent to balloon dilation. At 8 days after TEVAR, the patient underwent aortic valve replacement via median sternotomy and was discharged without a complication.

[Minimally Invasive Cardiac Surgery for a Heart Tumor after Breast Cancer Therapy and Partial Lung Resection for Lung Cancer;Report of a Case]

Papillary fibroelastoma is a benign tumor of the heart, constituting less than 10% of heart tumors. When papillary fibroelastoma is diagnosed, surgical treatment must be considered because it may cause embolization such as myocardial infarction and strokes. We experienced a patient with papillary fibroelastoma of the tricuspid valve after total resection of the right breast for breast cancer and partial lung resection for lung cancer. Minimally invasive cardiac surgery (MICS) with right thoracotomy was perfomed to resect the tumor. Though median sternotomy is still the most widely used approach for cardiac tumor, MICS is a useful method for preventing sternal wound infection and promoting wound healing, particularly in a patient with high risk of wound infection like this case.

A Novel Shape-Memory Monofilament Suture for Minimally Invasive Thoracoscopic Cardiac Surgery

OBJECTIVES

Endoscopic knot tying can complicate or prolong minimally invasive surgical procedures. A novel shape-memory monofilament suture with a spiral tail has been developed to speed up suture fixation during minimally invasive cardiac surgery. The purpose of this study was to evaluate its usefulness and safety in minimally invasive cardiac surgery.

METHODS

We installed a needle with a 4-0 monofilament suture, composed of polyvinylidene difluoride and hexafluoropropylene copolymers, in an originally invented jig and heated it in an oven. By only passing through the needle and then into the spiral made at the tail of the suture, a hangman's knot was easily made. For the fundamental experiment, to evaluate the effectiveness of the novel shape-memory monofilament suture, 4 surgeons with varying thoracoscopic experience tied knots within a simulated minimally invasive setting, using both the novel shape-memory and conventional monofilament sutures. The time elapsed for knot tying and tensile strength of each knot was measured.

RESULTS

The mean knot-tying time was significantly shorter with the novel suture than with the conventional suture (108 ± 29 vs. 172 ± 42 seconds, P = 0.01). The ultimate tensile strength of each knot was 17.4 N in the novel suture and 16.5 N in the conventional suture.

CONCLUSIONS

The novel shape-memory monofilament suture has great potential for reducing operative time of minimally invasive thoracoscopic surgery while retaining the strength of the knot.

Robotic mitral valve plasty for mitral regurgitation after blunt chest trauma in Barlow's disease

We successfully treated a case of mitral regurgitation due to chest trauma in Barlow's disease. A 71-year-old man was admitted with severe mitral regurgitation after blunt compression of the chest by a heavy object 5 months earlier. Preoperative examination revealed wide chordae tendineae rupture and myxomatous changes to the bileaflets. Neo-chordae reconstruction of the anterior mitral leaflet using loop technique, triangular resection of the posterior mitral leaflet, and ring annuloplasty was performed via surgical robot. Robotic mitral valve plasty for severe mitral regurgitation due to chest trauma in Barlow's disease was achieved safely with good clinical and excellent cosmetic results.

[Emergency Thoracic Endovascular Aortic Repair of Ruptured Kommerell's Diverticulum with an Acute Aortic Dissection]

This case report describes emergency thoracic endovascular aortic repair (TEVAR) of a ruptured Kommerell's diverticulum associated with a type B acute aortic dissection in a patient with a right aortic arch. A 64-year-old male was admitted with symptoms of sudden paraplegia and shock. The computed tomography imaging showed right aortic arch anomaly, with mirror image branching of the major arteries. The aorta was dissected from the origin of the right subclavian artery to the terminal aorta, with a thrombosed false lumen. Rupture was found in a 6.3 cm aneurysm located in the distal arch, which was diagnosed as Kommerell's diverticulum. We performed emergency TEVAR, and the aneurysm was successfully excluded using deployment of a Gore Tag stent-graft. At 3 months' follow-up, the patient was doing well and showed shrinkage of the aneurysm was confirmed. TEVAR is considered to be a suitable procedure for an emergency aortic catastrophe even in patients with aortic anomaly.

Chitosan tubes can restore the function of resected phrenic nerves

OBJECTIVES

We previously reported that the phrenic nerve could be morphologically repaired by implantation of a chitosan nanofibre tube (C-tube). In the current study, we investigated whether implantation of C-tubes could improve the function of an injured phrenic nerve using a beagle dog model.

METHODS

Seven beagle dogs underwent right thoracotomy under general anaesthesia. An approximately 5 mm length of the right phrenic nerve was resected. Five dogs had a C-tube implantation (C-tube group) and other two dogs did not have the C-tube implantation (control group). Diaphragm movements were longitudinally measured by X-ray fluoroscopy before surgery, immediately after the surgery, and 3, 6 and 12 months after the surgery. The diaphragm movement was determined by diaphragm levels at inspiration and expiration phases, and the excursion difference between them was calculated. At 12 months after the surgery, rethoracotomy was performed to examine electrical phrenic nerve conduction. The C-tube and phrenic nerve were then excised for histological assessment of nerve regeneration.

RESULTS

Three of the five animals of the C-tube group showed improvement of diaphragm movement with time. In these three animals, slow phrenic nerve conduction was observed. Histological assessment showed that the injured nerve was connected by newly regenerating nerve fibres surrounded by granulation tissue within the C-tube. On the other hand, the animals in the control group and two animals of the C-tube group showed neither improved diaphragm movement, nor electrical conduction to the diaphragm. No nerve fibre regeneration was found by histology.

CONCLUSIONS

Our results suggest that, in addition to morphological improvement, C-tube implantation can functionally improve the injured phrenic nerve by promoting phrenic nerve regeneration.

[Robot assisted tumor resection of an asymptomatic right atrial intracardiac lipoma; report of a case]

Primary cardiac tumors are relatively rare. No therapeutic guidelines have been established for the surgical indications of such cases. This creates therapeutic dilemmas, especially when the patient is asymptomatic. We describe the robot-assisted resection of an asymptomatic right atrial lipoma. A 63-year-old female was diagnosed to have a round mobile lipoma, measuring 27 mm in diameter in the right atrium near the junction with the inferior vena cava (IVC). Although she was asymptomatic, a surgical resection was indicated since the lipoma could cause an embolism or IVC obstruction due to its morbidity and potential to enlarge. Surgery was performed using the da Vinci Surgical System. A right-sided approach was used through 4 ports. The tumor was resected with a small portion of the right atrial wall. The total operation time was 214 minutes, and the total pump time was 84 minutes. The operation was performed while the heart was beating.

Inferior vena cava occluder for remote access perfusion in robotic cardiac surgery

Robotic cardiac surgery requires remote access perfusion. We have developed an inferior vena cava (IVC) occluder that can safely and conveniently drain blood from the IVC. This device has been clinically applied in one patient, as described herein. The framework for this device is made from a single superelastic nitinol wire, 0.30 mm in diameter. Diameter of the spreading site of the device is decided from computed tomographic images. A polyester fabric membrane (thickness 0.10 mm) is set at the tip of this framework. The occluder is deployed through an 18-F sheath. This device was used in a 64-year-old woman with lipoma in the right atrial wall near the IVC-right atrium interface. In this patient, it might not have been possible to completely reset the tumour by conventional IVC occlusion using a snare. The occluder was smoothly and safely deployed and retracted. During placement of the occluder, blood did not flow from the IVC into the right atrium. During extracorporeal circulation, vacuum drainage was performed with no air contamination. The tumour was resected by a three-arm da Vinci Surgical System. The IVC occluder needs to completely block the IVC and avoid obstructing the inflow region of the hepatic vein. This device obviates the need to place a snare on the IVC, and thus should directly improve the safety of robotic cardiac surgery and shorten the operating time.