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.

[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.

[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.

[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.

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.

Isthmus of a horseshoe kidney overlying a ruptured abdominal aortic aneurysm: a case report.

Horseshoe kidney is a rare congenital anomaly showing various degrees of fusion and accessory blood supply. Coexistence of horseshoe kidney and aortic aneurysm therefore presents a technical challenge to vascular surgeons. We report an 83-year-old woman with a ruptured abdominal aortic aneurysm associated with horseshoe kidney. Preoperative computed tomography (CT) showed discontinuity of the aneurysm wall in relation to the isthmus of the horseshoe kidney, and rupture of the aneurysm into the retroperitoneal space. The aneurysm was exposed via a transperitoneal approach, and grafting was performed successfully together with division of the isthmus of the horseshoe kidney. Renal function showed no impairment postoperatively.

Total right ventricular exclusion improves left ventricular function in patients with end-stage congestive right ventricular failure.

BACKGROUND: We developed a total right ventricular (RV) exclusion procedure for the treatment of isolated congestive RV failure. The objective of the present study was to elucidate the effects of a complete removal of RV volume overload (RVVO) on the surgically created single left ventricle (LV). METHODS AND RESULTS: Three adults (2 arrhythmogenic RV dysplasia, 1 Ebstein) and 5 children (all Ebstein) in NYHA class IV underwent the procedure. The RV free wall was resected from the heart, and the tricuspid orifice was closed. Pulmonary blood supply was obtained by a cavopulmonary connection in 6 patients and a systemic-pulmonary shunt in 2. The LV function was evaluated by 2-dimensional echocardiography 1 month after the surgery. All patients are alive. The paradoxical movement of the interventricular septum and geometry of the LV expressed by its eccentricity (2.1 to 1.2, P<0.01) were normalized after the operation in all 8 patients. LV end-diastolic volumes (59% to 109% of normal value, P<0.01), indexed maximal left atrial area (6.5 to 10.5 cm2/m2, P<0.01), LV ejection fraction (27% to 62%, P<0.01), and cardiac index (2.1 to 3.3 L/min/m2, P<0.05) all significantly increased. CONCLUSIONS: Removal of the RVVO by means of the total RV exclusion procedure provides effective volume loading, restores a cylindrical shape, and improves contractile function of the LV, thus leading to increased systemic output.

Living-donor lobar lung transplantation for various lung diseases.

OBJECTIVE: We report on our early experience in living-donor lobar lung transplantation for patients with various lung diseases including restrictive, obstructive, septic, and hypertensive lung diseases. METHODS: From October 1998 to March 2002, living-donor lobar lung transplantation was performed in 14 patients with end-stage lung diseases. There were 11 female patients and 3 male patients, with ages ranging from 8 to 53 years, including 4 children and 10 adults. Diagnoses included primary pulmonary hypertension (n = 6), idiopathic interstitial pneumonia (n = 2), bronchiolitis obliterans (n = 2), bronchiectasis (n = 2), lymphangioleiomyomatosis (n = 1), and cystic fibrosis (n = 1). Bilateral living-donor lobar lung transplantation was performed in 13 patients and right single living-donor lobar lung transplantation was performed for a 10-year-old boy with primary pulmonary hypertension. RESULTS: All the 14 patients are currently alive with a follow-up period of 4 to 45 months. Although their forced vital capacity (1327 +/- 78 mL, 50.2% of predicted) was limited at discharge, arterial oxygen tension on room air (98.5 +/- 1.8 mm Hg) and systolic pulmonary artery pressure (24.8 +/- 1.6 mm Hg) were excellent. Forced vital capacity improved gradually and reached 1894 +/- 99 mL, 67.4% of predicted, at 1 year. All donors have returned to their previous lifestyles. CONCLUSIONS: Living-donor lobar lung transplantation can be applied to restrictive, obstructive, septic, and hypertensive lung diseases. This type of procedure can be an alternative to conventional cadaveric lung transplantation for both pediatric and adult patients who would die soon otherwise.

Anastomosis of an anomalous segmental vein with the azygos vein in living-donor lobar lung transplantation.

We report the case of a living-donor lobar lung transplantation in which we found an abnormal segmental vein in the right lower lobe of the donor lung. The abnormal vein was anastomosed to the azygos vein of the recipient so that lung edema and congestion could be avoided. This alternative technique is effective in living-donor lobar lung transplantation when the superior segmental vein in the right lower lobe of the donor drains into the superior vein.

Reversal of chronic cyclosporine nephrotoxicity after heart transplantation-potential role of mycophenolate mofetil.

BACKGROUND: Chronic cyclosporine nephrotoxicity (CCN) after heart transplantation is a progressive condition that may lead to end-stage renal failure. The extent to which CCN is reversible with reduction or withdrawal of cyclosporine therapy is unknown. The aim of this study was to assess the reversibility of CCN and to assess the safety and efficacy of a strategy of cyclosporine dosage reduction, combined with conversion from azathioprine to mycophenolate mofetil (AZA/MMF switch) to maintain immunosuppression. METHODS: An AZA/MMF switch followed by cyclosporine dose reduction was undertaken in 30 heart transplant recipients (23 men, 7 women; mean age, 54 +/- 2 years) with established CCN at a mean of 90 +/- 9 months after transplantation (range, 17-182 months). The mean maintenance MMF dosage was 2.3 +/- 0.1 g/day (n = 28). Mean cyclosporine dosage was decreased from 2.3 +/- 0.2 mg/kg/day before AZA/MMF switch to 1.6 +/- 0.2 mg/kg/day. RESULTS: Three patients (10%) were withdrawn from MMF, 2 because of diarrhea and the third because of severe pneumonia that developed within 2 weeks of AZA/MMF switch. All 3 were restabilized with AZA. One patient (4%) experienced acute rejection 7 months after AZA/MMF switch. This resolved after an oral pulse of prednisolone. Systemic infections occurred in 6 patients within 12 months of AZA/MMF switch. Actuarial survival 1 year after AZA/MMF switch was 86% +/- 6%. One patient died of infection and 3 of other causes. Serum creatinine concentration decreased from 248 +/- 15 micromol/liter before cyclosporine dosage reduction to 193 +/- 11 micromol/liter and 206 +/- 19 micromol/liter at 3 and 12 months after dosage reduction (both p < 0.01 versus baseline, n = 23). Of the 23 patients who remained on MMF at 12 months, a decrease in serum creatinine was documented in 19 (83%). Four patients showed no improvement or showed deterioration in renal function, and three of these progressed to end-stage renal failure. CONCLUSIONS: Chronic cyclosporine nephrotoxicity has a significant reversible component in most patients. A strategy of AZA/MMF switch combined with cyclosporine dosage reduction is generally well tolerated and results in short-term improvement in renal function in most patients. Close vigilance is required during the first 12 months after AZA/MMF switch because both acute rejection and infection may occur.

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.