Virtual Reality Computed Tomography Evaluation　- Anatomy and Clinical Implications for Valve-Sparing Aortic Root Replacement.

BACKGROUND: Three-dimensional aortic root evaluation using virtual reality (VR) techniques for valve-sparing aortic root replacement (VSARR) preparation has not yet been implemented, so we demonstrated VR computed tomography (VR-CT) and assessed its utility for VSARR.Methods and Results: We enrolled 72 patients who underwent multidetector CT before elective VSARR for annuloaortic ectasia with tricuspid aortic valve. The geometries of their aortic roots were measured with a VR-CT workstation. The mean values of geometric height (GH), free margin length (FML), and commissural height (CH) were 17.2±2.4 mm, 36.0±5.2 mm, and 24.0±4.3 mm, respectively. The right coronary/noncoronary CH was significantly greater than the left coronary/right coronary and left coronary/noncoronary CH. The left coronary cusp had the shortest FML, intercommissural distances (ICD), and smallest central angle. Although the right coronary cusp had the largest values for FML, ICD, and central angle, the right coronary cusp had the lowest GH and EH. The VR-CT measurements strongly correlated with intraoperative alternatives, especially with mean GH (R2=0.75) and left coronary/noncoronary CH (R2=0.79). Furthermore, mean GH was observed to be significantly different among the selected graft size groups; therefore, the preoperative mean GH could play a significant role in graft sizing. CONCLUSIONS: VR-CT evaluation allows a thorough understanding of aortic root anatomy, which could facilitate VSAAR.

[Thoracic Endovascular Aortic Repair for Stanford Type B Acute Aortic Dissection with Right Leg Malperfusion:Report of a Case].

We report a case of complicated Stanford type B acute aortic dissection with malperfusion to the right leg. The patient received conservative treatment in a previous hospital. However, he complained of pain in the right leg, which had been gradually turning pale. The patient was diagnosed with complicated Stanford type B acute aortic dissection with right leg malperfusion and was transferred to our hospital for treatment. Thoracic endovascular aortic repair (TEVAR) to close the entry to the distal aortic arch was performed, and we embolized the left subclavian artery to prevent type Ⅱ endoleak and to extend the stent-graft landing zone. We implanted a bare stent into the right external iliac artery to enlarge its true lumen. The patient was discharged from our hospital 22 days postoperatively. After the operation, computed tomography( CT) scan showed an aortic false lumen remodeling.

[Our Experience and Technical Improvement in Robot-assisted Cardiac Surgery].

Since 2014, we have used the da Vinci surgical system to perform internal thoracic artery harvest in minimally invasive direct coronary artery bypass (MIDCAB), and since 2016, we have also performed robot-assisted cardiac surgery( RACS) for mitral and tricuspid valve surgery, left atrial thrombosis, and myxoma, all of which we have had performed as minimally invasive cardiac surgery( MICS) previously. Even after the introduction, different ideas (Chordalizer, COR-KNOT, special long CP cannula, de-air technique, etc.) were developed. As a result of the learning curve, more stable surgery could be performed. However, keeping in mind that RACS is only a means and not a purpose, the RACS indication should always be carefully considered. When problems, such as intracardiac manipulation or uncontrollable bleeding, occur, safe surgery must be decided to switch to normal thoracotomy as soon as possible. A further enhancement would be expected for even better results and expansion of the RACS indications.

Virtual reality-guided aortic valve leaflet reconstruction for type 0 bicuspid aortic stenosis.

Although virtual reality (VR) techniques that enable visualizing a patient's anatomy stereoscopically have been developed recently, these techniques are still scarcely used in clinical settings, and their benefits remain uncertain. Herein, we demonstrate how VR preoperative planning facilitated the efficiency of a complex surgical procedure. A 53-year-old male was diagnosed as type 0 bicuspid aortic stenosis. To take haemodynamical advantage and to lower valve-related reoperation risks, an aortic valve reconstruction was scheduled; however, anatomical tri-leaflet neocuspidalization for type 0 bicuspid aortic root is particularly challenging. To optimize the procedure, VR preoperative planning was applied to create a blueprint of the aortic root rearrangement and suture line design. This allowed for a competent aortic valve to be reconstructed speedily, resulting in an excellent postoperative course.

Aortic valve replacement and coronary artery bypass grafting through a right thoracotomy for a patient with a left chest wall tumor.

A 68-year-old man was diagnosed with severe aortic stenosis and right coronary artery occlusion on preoperative examination for total extirpation of a giant left breast liposarcoma. Prior to the intervention for the liposarcoma, he underwent successful aortic valve replacement and coronary artery bypass grafting via a right anterolateral thoracotomy to avoid the tumor close to the sternum. On postoperative day 28, the patient underwent a successful wide excision of the left chest wall tumor.

A simple technique of artificial chordae implantation in robotic cardiac surgery using a novel tube device supporting expanded polytetrafluoroethylene chordae ligation.

Artificial chordae implantation is an important technique for treating leaflet lesions in mitral valve repair. Considering that the expanded polytetrafluoroethylene (ePTFE) suture is slippery on the surface, adequate ligation without laxity should be critically considered, especially in robotic surgery. To resolve this issue, we applied a novel device that controls the length of an ePTFE suture (Chordarizer) for artificial chordae implantation in robotic mitral valve repair. After assessing the mitral valve via the right side of the left atrium, we stitched a CV-4 ePTFE suture to the target papillary muscle. Using a calliper, we measured the length of the artificial chordae and passed the CV-4 through the appropriate Chordarizer. Then, we stitched the CV-4 to the tip of the leaflet from the left ventricle side and tied it using da Vinci arms. Finally, the Chordarizer was peeled away. Chordarizer ensured safe and reliable artificial chordae implantation procedures with robotic mitral surgery, by maintaining the desired CV4 length.

[Simultaneous Surgery of Gastrectomy and Rerouting of the Pre-existing Right Gastroepiploic Artery Bypass Graft for Gastric Cancer].

The patient was a 76-year-old man with advanced gastric cancer who had a history of coronary artery bypass grafting using the right gastroepiploic artery. Although coronary angiography confirmed the patency of all the coronary artery bypass grafts, his right gastroepiploic artery was required to be cut for curative gastrectomy. To prevent serious myocardial ischemia, rerouting of the right gastroepiploic artery graft was performed using a saphenous vein graft via right mini-thoracotomy. The proximal end of the saphenous vein graft was anastomosed to the ascending aorta. Then, gastrectomy via epigastric median re-laparotomy was performed. His postoperative course was uneventful.

Robotic Transmitral Approach for Hypertrophic Cardiomyopathy With Systolic Anterior Motion.

BACKGROUND: Surgical intervention is indicated in symptomatic hypertrophic cardiomyopathy (HCM) patients with a ventricular outflow pressure gradient more than 50 mmHg. The transmitral approach, along with the transapical and transaortic approaches, is routinely used for myectomy, but all are open procedures. We describe a robotic transmitral approach that can be used to resolve septal hypertrophied muscle and eliminate mitral regurgitation (MR) using 1 cardiac incision. Methods and Results: We retrospectively analyzed 20 adult patients with obstructive HCM who exhibited concomitant severe MR and systolic anterior motion (SAM). The 2 groups comprised 12 standard full-sternotomy transaortic and 8 robotic transmitral approaches. The pre-intraventricular pressure gradient was 69±14.2 mmHg in the robotic transmitral group and 70.2±17.4 mmHg in the transaortic group (P=0.876). Both groups had a similar left ventricular ejection fraction (65±8% vs. 72±9%, P=0.901) and maximal ventricular wall thickness (22.3±4.5 and 21.7±6.0, P=0.835). Postoperative MR was reduced to less than grade II in all patients. In the robotic group, the postoperative pressure gradient was 1.5±2.6 mmHg, which was lower than that of the transaortic group at 10.6±10.8 mmHg (P=0.019). The cross-clamp time was 95.3±7.7 min in the robotic group and 104.7±20.8 min in the transaortic group (P=0.193). The operation time was 237.5±22.4 and 309.6±28.5 min (P<0.01) in the robotic transmitral and transaortic groups, respectively. CONCLUSIONS: Using a robotic transmitral approach to treat with patients with HCM, SAM, and MR is feasible and reliable. Through 1 atrial incision, it is possible to resolve hypertrophy of the septum and eliminate both severe MR and SAM.

[Usefulness of Balloon Aortic Valvuloplasty for Determining the Operative Procedure in a Patient with Severe Aortic Stenosis Complicated with Secondary Mitral Regurgitation;Report of a Case].

A 59-year-old man on chronic hemodialysis presented with severe aortic stenosis(AS) and moderate mitral regurgitation (MR). Although aortic valve replacement was scheduled, his status deteriorated into New York Heart Association(NYHA) class III heart failure due to the exacerbation of AS and concomitant MR. Double valve replacement was considered to be too high risk for the patient, and balloon aortic valvuloplasty(BAV) was initially performed. As a result, the mean pressure gradient of the aortic valve decreased from 65 to 28 mmHg and the mean pulmonary pressure also from 52 to 33 mmHg. Furthermore, MR improved from severe to moderate following BAV. We considered the alleviation of aortic stenosis was sufficient treatment for the patient. He underwent aortic valve replacement on the following day of BAV. Postoperative echocardiogram after 1 month showed mild MR, and the estimated pulmonary systolic pressure was 35 mmHg. During the 1-year follow up, MR was not aggravated. BAV might be a useful diagnostic method to determine the operative strategy for severe AS complicated with secondary MR.

Reconstruction of aorto-mitral continuity with a handmade aorto-mitral bioprosthetic valve for extensive bivalvular endocarditis.

Surgical treatment is effective to exclude all infected tissue in patients with infective endocarditis. Although various techniques have been reported, it has remained a great challenge for patients with extensive infected regions. A patient with extensive bivalvular endocarditis including the aortic and mitral valve and aorto-mitral continuity is described. A handmade aorto-mitral bioprosthetic valve was created to reconstruct the defect after extensive debridement. The patient was discharged on the 30th postoperative day without inflammatory signs.

Simple and safe graft insertion in the elephant trunk technique.

The elephant trunk technique is a well-established procedure, but aortic wall injury or aneurysmal rupture may occur if the graft is forcibly pushed to insert it into the distal aorta. We have developed simple and safe insertion technique using a syringe.

Acute subdural hematoma following thoracoabdominal aortic repair in a patient with Marfan syndrome: a rare complication of cerebrospinal fluid drainage.

Cerebrospinal fluid (CSF) drainage is a routinely used adjunct in operation of thoracoabdominal aortic aneurysm (TAAA), which may reduce the incidence of perioperative paraplegia by improving spinal cord perfusion. Neurological complications of CSF drainage have been reported, possibly due to excessive CSF drainage, and acute subdural hematoma (SDH) in particular may lead to catastrophic complications. We present a rare case of acute SDH due to CSF drainage that was not excessive, after TAAA repair in a patient with Marfan syndrome, who recovered without invasive treatment.

Mitral valve repair in a patient with acromegaly.

We report on a successful mitral valve (MV) repair and modified Cox maze procedure in a 35-year-old male patient with acromegaly, associated with severe mitral regurgitation and atrial fibrillation. He underwent a transsphenoidal adenomectomy, 7 months after the cardiac operation, and IGF-I level was normalized postoperatively. Valvular disease in patients with acromegaly is associated with hormonal activity, and control of growth hormone and insulin-like growth factor I excesses is important in the long-term durability of mitral valve repair.

Mitral valve repair in a patient with myelodysplastic syndrome.

Open heart operations for patients with myelodysplastic syndrome (MDS) are associated with infective and bleeding complications. We report a 67-year-old woman with rheumatic, severe mitral regurgitation and mitral stenosis associated with MDS who underwent a mitral valve (MV) repair. Commissurotomy was performed in the anterior commissure. Autologous pericardial patch treated with glutaraldehyde solution was prepared. The anterior leaflet was completely detached from the posterior to the anterior commissure. The anterior leaflet was augmented by autologous pericardial patch treated with glutaraldehyde solution and three pairs of artificial chordae were implanted. Postoperative transesophageal echocardiography showed an increase in the MV orifice and less than trivial mitral regurgitation. Two years after the operation, the patient has normal sinus rhythm with no deterioration of the MV lesion by transthoracic echocardiography. Although the feasibility of MV repair is low in patients with restrictive pathology due to rheumatic disease, MV repair may be preferred in patients with MDS.

Significance of mitral valve repair for active-phase infective endocarditis.

Mitral valve repair is preferred to replacement in infective endocarditis, but in the active phase, it often requires extensive debridement of infected tissue and complex reconstruction. We investigated 22 consecutive native mitral valve operations during active-phase infective endocarditis. The time from initiation of medical treatment to operation was 16.8 ± 16.4 days. Mitral valve repair was performed in 15 (68.2%) patients, using prosthetic annuloplasty in 14, an autologous pericardial patch in 11, and artificial chordal replacement in 9. Hospital mortality was 9.1% (2 patients), due to subarachnoid hemorrhage and pneumonia. One patient died 26 months after valve replacement due to congestive heart failure. The postoperative left ventricular end-diastolic dimension was significantly smaller (45.7 ± 5.6 vs. 53.3 ± 10.2 mm) and ejection fraction was significantly higher (57.0% ± 14.7% vs. 40.1% ± 8.2%) in patients who underwent valve repair compared to those who had valve replacement. Mitral regurgitation requiring reoperation occurred in 3 patients during follow-up. Mitral valve repair is feasible in active-phase infective endocarditis, and results in improved regression of left ventricular dimensions compared to valve replacement. However, complex mitral valve repair with extensive leaflet resection may not have long-term durability.

Granulomatous endocarditis in a patient with Wegener's granulomatosis.

Echocardiographic examination of patients with granulomatous endocarditis in patients with Wegener's granulomatosis (WG) reveals vegetation-like lesions that may be misdiagnosed as infective endocarditis resulting in inappropriate therapy. Three-dimensional transesophageal echocardiography aids differential diagnosis. Here, we report the case of a WG patient with associated mitral and aortic granulomatous endocarditis. Although the patient was treated with prednisolone and cyclophosphamide, serial echocardiography did not reveal any significant changes in disease course.

Aortic valve replacement in a patient with alpha-thalassemia.

Cardiac valve disease resulting from elastic tissue defects has been demonstrated in patients with beta-thalassemia; however, valve disorders of patients with alpha-thalassemia have been rarely discussed. We present the case of a patient with alpha-thalassemia and severe aortic regurgitation with left ventricular dysfunction. The patient underwent successful aortic valve replacement with mechanical prosthesis. Histopathology of the excised valve showed elastic tissue disruption and chronic thrombus on the ventricular side. Hypercoagulative states have been observed in patients with alpha-thalassemia as beta-thalassemia; therefore special attention should be taken in perioperative anticoagulation therapy.

Large primary cardiac sarcoma on the left ventricular free wall: is total excision contraindicated?

A case of a large primary cardiac sarcoma on the left ventricular free wall is reported. Although the definitive diagnosis of this tumor was not made preoperatively, total excision was planned for rapid diagnosis and optimal procedure. However, the operation was discontinued due to intraoperative diagnosis of malignancy. As a result, the patient suffered from the symptoms of cardiac tamponade caused by the large tumor. We discuss the surgical strategy to provide therapeutic benefit for possible patients in the future. In conclusion, an aggressive attempt at volume reduction such as cardiac autotransplantation may relieve the symptoms, even though such surgery would only be palliative.