[Posterior Mediastinal Cyst Resection during Cardiac Surgery through Median Sternotomy:Report of a Case].

A 47-year-old man presented with hematuria. Computed tomography( CT) showed a posterior mediastinal cyst. Chest magnetic resonance imaging showed a well defined mass with high intensity on T2-weighted images. Echocardiogram revealed severe aortic regurgitation, moderate mitral regurgitation and no continuity between the cyst and the pericardium. We performed aortic valve replacement, mitral annuloplasty and cyst resection after confirming it was not malignant by intraoperative rapid pathological examination. We performed sufficient and safe cyst resection through full sternotomy under cardiac arrest. Pathological examination revealed that cyst was bronchogenic. Bronchogenic cyst has malignant potential and it is very difficult to resect after presenting symptoms. We need to consider the differential diagnosis, the timing of operation and operative strategy.

[Preoperative Evaluation of Saphenous Vein Graft Using Plain Computed Tomography for Endoscopic Saphenous Vein Harvesting].

We report the preoperative evaluation of saphenous vein (SV) graft using plain computed tomography (CT) for endoscopic saphenous vein harvesting (EVH). We made three-dimensional (3D) images of SV by using plain CT images. EVH was performed in 33 patients from July 2019 to September 2020. The mean age of the patients was 69±23 years, and 25 patients were men. The success rate of EVH was 93.9%. Hospital mortality was 0%. Postoperative wound complications was 0%. The early patency was 98.2% (55/56). 3D images of SV by plain CT are very important information for EVH because of surgical procedure in a closed space. Early patency is good and mid and long term patency of EVH may be improved due to safety and gentle technique by CT information.

[Incidental Diagnosis of Giant Cell Myocarditis at Open Heart Surgery:Report of Case].

Giant cell myocarditis (GCM) is one of the rare diseases that cause fatal heart failure and suspected to be associated with autoimmune disorder. There are few reports that the patients of GCM live long because of their progressive heart failure. We report a rare case of patient who was suspected two long hospitalizations due to heart failure in her childhood and peripartum period, and incidentally diagnosed with GCM by myocardial biopsy performed at the aortic valve replacement and mitral annuloplasty for severe aortic valve regurgitation and moderate mitral regurgitation.

[Coronary Artery Bypass Grafting and Mitral Annuloplasty in a Patient with Left Ventricular Noncompaction with Low Ejection Fraction:Report of a Case].

A 71-year-old man who hospitalized frequently for heart failure was referred to our hospital for severe coronary disease with mitral regurgitation. Transthoracic echocardiography revealed marked left ventricular dilatation, low ejection fraction (20%) and moderate mitral regurgitation with leaflet tethering. It also revealed myocardium with prominent trabeculations and deep intertrabecular recesses. Coronary angiography showed triple vessel disease. Coronary artery bypass grafting and mitral annuroplasty was performed. Coronary microcirculatory dysfunction by left ventricular noncompaction( LVNC) and myocardial ischemia made us pay more attention to myocardial protection. Aortic cross clamp time was 67 minnutes, total cardiopulmonary bypass time was 116 minnutes and operation time was 214 minnutes. The postoperative course was uneventful and the patient was discharged 15 days after the operation. Postoperative echocardiography revealed no mitral regurgitation and improving left ventricular function. Postoperative coronary computed tomography showed all grafts patent. Careful observation of cardiac function is vital because of the possibility of progression to heart failure in a patient with LVNC.

[Aortic Valve Replacement through an Upper Hemisternotomy in an Eldery Patient with Heart Failure:Report of a Case].

Cardiac surgery for elder patients should be minimally invasive because of their frailty and concomitant multiple chronic diseases. We performed aortic valve replacement (AVR) via upper hemisternotomy (UHS) on an 85-year-old patient who suffered from severe aortic regurgitation with dobutamine support. The postoperative course was uneventful. AVR via UHS is safer than that via right axiallary thoracotomy AVR with shorter aortic cross-clamp time, shorter cardiopulmonary bypass time and fewer complications. AVR via UHS makes ambulation and rehabilitation easier than AVR via full sternotomy, because of thoracic stability. It is more effective and should be more prevalent as minimally invasive cardiac surgery for eldery patients with frailty.

Acute aortic regurgitation following fibrous strand rupture of aortic valve successfully diagnosed by transesophageal echocardiography.

Fibrous strand rupture is a rare cause of acute aortic regurgitation, but is a serious condition because of acute massive regurgitation. Therefore, prompt and accurate diagnosis is required. We saw a 53-year-old man who presented with acute dyspnea without evidence of infection. Transesophageal echocardiography revealed severe aortic regurgitation because of fibrous strand rupture. We performed surgery and found that the fibrous strand of the right coronary leaflet was ruptured. In cases of acute aortic regurgitation, the rupture of fibrous strand should be considered and transesophageal echocardiography would be very useful to diagnose it.

[Intraoperative Endoscopic Evaluation of the Aortic Valve in Aortic Valve Repair].

This report discusses intraoperative endoscopic evaluation of the aortic valve performed in 2 cases of aortic valve repair. The "direct" or real image by the endoscopy helped to confirm the preoperatively-known lesion and even to detect a new legion which was not detected preoperatively. The endoscopy also enabled the evaluation of the aortic valve under the pressure-loaded condition without releasing the aortic clamp. Postoperative aortic regurgitation was grade I or less in both cases, although it progressed to grade II at 1 year in case 2. Echocardiographic parameters demonstrated no change in the size of the aortic root configuration for 8 and 5 years in case 1 and case 2, respectively. Intraoperative aortic endoscopy was useful to define the pathogenesis of aortic regurgitation and to evaluate the cusp repair procedures, which may contribute to a good mid-term result of aortic valve repair.

Clover stitch technique for aortic valve in mitral valve repair.

In the case of mitral repair with severe aortic regurgitation, aortotomy and selective cardioplegia are necessary for myocardiac protection. In this situation, the saline test for mitral valve repair cannot be accomplished due to incomplete left ventricular filing. In patients undergoing mitral valve repair concomitant with severe aortic valve insufficiency, after cardiac stand still was achieved by selective cardioplegia. Each center of the aortic leaflet, termed the node of Arantius, was stitch up using a 5-0 polypropylene suture, forming a clover leaflet shape. This stitch inhibits aortic valve opening and reduces saline leakage thorough aortic valve. We have termed this procedure as the "Clover Stitch Technique". Upon completion of this technique, mitral valve repair can be undertaken via a right-side left atrial incision. This technique enables accurate evaluation of mitral valve morphology or the extent of regurgitation, repeatedly without complicated manipulations during and after mitral valve repair.

Endoscopic evaluation technique using a camera port for valve-sparing root reconstruction.

Intraoperative aortic valve evaluation should be accurate in valve-sparing root replacement to minimize postoperative aortic valve regurgitation. Ascending aorta de-clamping and weaning of cardiopulmonary bypass are required in intraoperative transoesophageal echocardiography. Aortic valve endoscopy aids in the magnification of structures and enables image sharing within the operative team. While a rigid endoscope and saline infusion line are directly inserted from the Valsalva graft end, a Kelly clamp is needed for graft gap closure, affecting the valve morphology due to graft deformation. The accurate inner pressure of the neo-Valsalva sinus cannot be measured in this method. We propose a technique to accurately evaluate aortic valve conformation using a balloon blunt-tip system that enables aortic valve evaluation under the measured pressure and without Valsalva graft deformation.

Ascending aortic replacement for acute type A aortic dissection in octogenarians.

OBJECTIVE: The management of acute type A aortic dissection in elderly patients is controversial. This study aimed to investigate the validity of ascending aortic replacement for acute type A aortic dissection in octogenarians compared with younger patients. METHODS: Twenty-five octogenarians, among 117 consecutive patients with acute type A aortic dissection between January 2000 and October 2013 who underwent emergency surgery, were reviewed retrospectively. The median age was 84 years (80-91 years). The patients were six men and 19 women. All 25 patients underwent ascending aortic replacement under deep hypothermic circulatory arrest. In the same period, 55 patients younger than 80 years with acute type A aortic dissection had ascending aortic replacement performed. Clinical data were prospectively entered into our institutional database. Late follow-up was 6.8 ± 2.8 years and was 100% complete. RESULTS: The 30-day mortality rate was 8% (2/25 patients), which was similar to that in patients younger than 80 years (5%). There were no reoperations in octogenarians and five reoperations in younger patients in the follow-up period. Survival at 1 and 5 years was 80.0 and 59.7% in octogenarians and 90.6 and 81.9% in younger patients, respectively (P = 0.036). CONCLUSION: Ascending aortic replacement for octogenarians with acute type A aortic dissection was successfully performed, resulting in satisfactory early and midterm survival. Aggressive surgical treatment is mandatory for improving the outcome in octogenarians with acute type A aortic dissection.

Impact of transapical aortic cannulation for acute type A aortic dissection.

OBJECTIVE: Early and mid-term result of transapical aortic (TAA) cannulation technique was evaluated compared with femoral artery (FA) cannulation in Acute Type A Aortic Dissection(AAAD). METHODS: From January 2000 to October 2013, 80 consecutive patients with AAAD were underwent the ascending aortic replacement at Nagasaki Kouseikai Hospital. These patients were divided into two groups according to the cannulation site, FA cannulation (n = 34) and TAA cannulation (n = 46). Early and mid-term outcomes were compared between two groups. RESULT: Preoperative patient characteristics were almost comparable between groups. The time from skin incision to starting cardiopulmonary bypass (CPB) was significantly shorter in the TAA group (45 ± 16 vs 23 ± 5.1 min; P <0.001). There were no significant differences in post-operative cerebral infarction in two groups (17% versus 11%; P = NS). The operative mortality rate was 8.8% in FA group and 4.3% in TAA group (P = NS). During follow up (mean, 6.8 years), survival at 3 years and 5 years was 77.4% and 71.9% in TAA group and 76.3% and 73.8% in FA group, respectively. CONCLUSION: The postoperative morbidity and mortality between the two groups were almost the same. TAA cannulation for acute Type A aortic dissection is faster, easy and safe with acceptable early and mid-term outcome.

Comparative Hemolysis Study of Clinically Available Centrifugal Pumps.

Centrifugal pumps have become important devices for cardiopulmonary bypass and circulatory assistance. Five types of centrifugal pumps are clinically available in Japan. To evaluate the blood trauma caused by centrifugal pumps, a comparative hemolysis study was performed under identical conditions. In vitro hemolysis test circuits were constructed to operate the BioMedicus BP-80 (Medtronic, BioMedicus), Sams Delphin (Sarns/3M Healthcare), Isoflow (St. Jude Medical [SJM]), HPM-15 (Nikkiso), and Capiox CX-SP45 (Terumo). The hemolysis test loop consisted of two 1.5 m lengths of polyvinyl chloride tubing with a 3/8 -inch internal diameter, a reservoir with a sampling port, and a pump head. All pumps were set to flow at 6 L/min against the total pressure head of 120 mm Hg. Experiments were conducted simultaneously for 6 h at room temperature (21o C) with fresh bovine blood. Blood samples for plasma-free hemoglobin testing were taken, and the change in temperature at the pump outlet port was measured during the experiment. The mean pump rotational speeds were 1,570, 1,374, 1,438, 1,944, and 1,296 rpm, and the normalized indexes of hemolysis were 0.00070, 0.00745, 0.00096, 0.00066, 0.00090 g/100 L for the BP-80, Sarns, SJM, Nikkiso, and Terumo pumps, respectively. The change in temperature at the pump outlet port was the least for the Nikkiso pump (1.8o C) and the most with the SJM pump (3.8o C). This study showed that there is no relationship between the pump rotational speed (rpm) and the normalized index of hemolysis in 5 types of centrifugal pumps. The pump design and number of impellers could be more notable factors in blood damage.

Comparison of limited and full sternotomy in aortic valve replacement.

OBJECTIVE: The practice of minimally invasive valve surgery remains controversial. The aim of this study was to evaluate the technical feasibility and postoperative course of aortic valve replacement through limited upper sternotomy compared to conventional full sternotomy. METHODS: From May 1998 to August 2000, we performed 24 cases of isolated aortic valve replacements through the limited upper sternotomy approach (group M). During the same period, 18 patients received isolated aortic valve replacements through the conventional full sternotomy approach (group C). Operation duration, postoperative course and laboratory data were compared between the two groups. RESULTS: All patients received a valve replacement with a prosthetic valve. There was no significant difference between the two groups in mean aortic cross-clamping time, mean cardiopulmonary bypass time or mean operation duration (skin to skin). No patient required blood transfusion. Patients in the group M were extubated earlier, with less postoperative blood loss and discharged earlier after the operation than those in group C. On the first postoperative day, the peak level of lactic acid dehydrogenease was significantly lower in the group M than those in group C. CONCLUSION: Limited upper sternotomy for aortic valve replacement resulted in shorter operation duration and minimized operative risks for the patients. We believe this method brings not only cosmetic benefits but also improved postoperative course.

Aortic valve replacement with smaller valve size.

The occurrence of prosthesis-patient mismatch after aortic valve replacement with a small valve size was evaluated in 249 patients, focusing on echocardiographic data. Aortic valve pathology included regurgitation in 174 patients and stenosis in 75. Echocardiography was performed in the early and late postoperative periods. A projected effective orifice area index < 0.85 cm(2)·m(-2) was noted in 56 patients; values ≥ 0.85 cm(2)·m(-2) were found in 128. Postoperative changes in ejection fraction, left ventricular mass regression, and peak transprosthetic gradient were similar in both groups. Small prostheses (≤ 19 mm) were used in 43 patients who had significantly higher postoperative transprosthetic gradients in both the early and late periods, compared to those with larger prostheses. Our findings show that the occurrence of prosthesis-patient mismatch after aortic valve replacement is rare. Left ventricular mass regression occurred in most patients, with acceptable transprosthetic gradients.

Predischarge angiographical evaluation of radial artery graft harvested by endoscopic harvesting system.

OBJECTIVE: Endoscopic radial artery harvesting (ERAH) has superior cosmetic advantages over conventional harvesting methods. With instrumental advancements, these techniques have become easier to adopt and require less time to learn. In most reported cases, the quality of harvested conduits is discussed based on macroscopic and histologic examinations and clinical outcomes. However, predischarge angiography gives a straightforward answer regarding quality of harvested conduit. The aim of this study is to assess the quality of endoscopically harvested radial artery by predischarge angiographic evaluation. METHODS: Endoscopic procedure using VasoView 4 system was performed in 87 patients between September 2004 and December 2007, and 78 predischarge angiographical evaluations were completed and reviewed. Mean age of the patients was 66 ± 10 years and 18% were women. After ERAH was performed, accompanying veins were dissected by ultrasound scalpel. All conduits were as aortocoronary bypass under cardiopulmonary bypass. RESULTS: Mean arm ischemic time was 32 ± 13 minutes and length of harvested conduit was 17.8 ± 1.3 cm. Predischarge angiography demonstrated two occlusions at the proximal anastomosis in the 51st and 71st cases, although intraoperative flow study showed normal flow patterns in both cases. Stenosis in the conduits was observed in the first, sixth, and seventh cases. No further angiographical problems were found in the remaining conduits. CONCLUSIONS: Based on the angiographical results, problems with the harvested conduits occurred only in initial period. ERAH with VasoView system provides satisfactory angiographical quality after initial learning curve.