Analysis of the elephant trunk method in patients with extensive thoracic aortic aneurysm

We assessed the appropriate length of an elephant trunk prosthesis based on our experience with 9 patients experiencing extensive thoracic aneurysms. There were 3 patients with a true aneurysm, 5 patients with a dissecting aortic aneurysm, and 1 patient with a true plus dissecting aortic aneurysm. The subjects were 4 men and 5 women and, at the time of operation, were from 38 to 74 years old. The second-stage operations were performed on 6 patients from 9 days to 6 months after the first-stage operation. In the first-stage operation, one patient died of pneumonia during the hospital stay and another died of multi-organ infarction after 15 months. In the second-stage operation, two patients died of brain hemorrhage in the chronic stage after the operation. The length of the elephant trunk prosthesis was 3 cm in the three early patients, and in one of them the elephant trunk could not be utilized due to its insufficient length. In the next three patients, the length was extended to 5 cm, but one of patient experienced an expansion of the aneurysm in the descending aorta due to a graft of insufficient length which could not decompress the aneurysmal wall. Therefore, in the last three patients, the length was further extended to 10 cm, and the second-stage operation was performed uneventfully on the 64th, 9th and 45th day, respectively after the first-stage operation within a continuous hospital stay. Neither expansion of the aneurysm nor thromboembolism was found during the waiting period for any of the second-stage operations. Accordingly, we recommend using a 10 cm elephant trunk prosthesis.     

A rare case of double aortic arch: Right thoracotomy and residual retroesophageal aortic arch

Summary The case of a 2-year-old boy with tetralogy of Fallot and a complete double aortic arch (both arches patent) is reported. The left dominant aortic arch ran retroesophageally to the right and joined with the right smaller arch to form the descending thoracic aorta on the right side. We employed a right thoracotomy and performed a division of the right nondominant arch at the connection with the descending aorta. The surgical implications of an unusual type of double aortic arch are discussed.     

Anticoagulation therapy and circulatory management with left ventricular catheter under left ventricular bypass using centrifugal pump--an experience in a case with mitral valve replacement

A 53-year-old woman who had severe mitral regurgitation associated with moderate tricuspid regurgitation and mild aortic regurgitation underwent mitral valve replacement with a 27 mm Bj?rk-Shiley mechanical valve, left atrial plication and tricuspid annuloplasty. She fell into low output syndrome on the first postoperative day because of persistent intractable ventricular arrhythmia and eventually required open cardiac massage. The left ventricular (LV) bypass using a centrifugal pump was initiated with cannulation to ascending aorta and left atrium. Echocardiography showed LV wall motion extremely poor with the prosthetic valve being in closed posture. For prevention from thrombus formation on the prosthetic valve and in the LV, a catheter was inserted into LV through RV to give heparin and monitor the LV pressure. As the result, activated clotting time of LV was higher (range from 280-388 sec) than that of systemic blood (range from 182-258 sec). Also, the change of LV pressure was monitored through this LV catheter. Under this monitor, IABP was smoothly applied in the presence of aortic regurgitation, and she was weaned from LV-bypass successfully after 157 hrs support. She was discharge on the 77th postoperative day without thromboembolic complication.     

Association of smooth muscle cell phenotypic modulation with extracellular matrix alterations during neointima formation in rabbit vein grafts.

PURPOSE: To clarify the mechanisms of structural changes underlying vein graft stenosis that limits efficacy of bypass grafting operation, we examined the accumulation and distribution of various extracellular matrix (ECM) components during neointima formation in rabbit vein grafts and analyzed their correlation with proliferation and phenotypic modulation of smooth muscle cells (SMCs). METHODS AND RESULTS: An autologous external jugular vein graft was transplanted into the carotid artery in 25 rabbits. After the restoration of blood flow, the graft was markedly dilated. Medial SMCs in the graft appeared to be injured, and they began to proliferate at day 4 and subsequently migrated and formed the neointima at day 7. The neointima observed at days 7 and 14 contained ECM components, including type I collagen, heparan sulfate, and chondroitin sulfate, and the intimal SMCs were phenotypically modulated from the differentiated-type (SM2-positive and SM embryonic-negative) to the dedifferentiated-type (SM2-negative and SM embryonic-positive) as determined with immunostainings for myosin heavy chain isoforms. The intimal SMC proliferation was maximal at 2 weeks and then decreased rapidly. However, the neointima continued to thicken thereafter throughout the 6-month period of the experiment, and ECM accumulation, such as type I collagen and decorin, a small dermatan sulfate proteoglycan, was a prominent feature observed in the hypocellular region of the deep intima from 2 months after the transplantation. The phenotype of the intimal SMCs gradually returned to the differentiated-type from the deep intima after 2 months, but a small number of the intimal SMCs remained in the dedifferentiated phenotype even at 6 months after the operation. CONCLUSION: The neointima in the vein graft was formed initially by means of migration and proliferation of the phenotypically modulated, dedifferentiated-type SMCs and continued to thicken by means of sustained ECM accumulation, including type I collagen and decorin, in association with the prolonged presence of the dedifferentiated-type SMCs. These chronologic features in cell kinetics and ECM accumulation may contribute to the frequent occurrence of graft wall thickening that occurs in the vein grafts.     

Optimum dose of cold potassium cardioplegia for patients with chronic aortic valve disease: determination by left ventricular mass

Twenty-eight patients with chronic aortic valve disease and left ventricular (LV) hypertrophy who underwent aortic valve replacement were studied. Angiographically obtained LV mass ranged from 113 to 580 gm (average, 292 gm). In 14 patients, the LV mass per square meter of body surface area was 200 gm or more. Cold glucose-insulin-K+ cardioplegic solution was infused to obtain a myocardial temperature of less than 15 degrees C. The initial dose of cardioplegic solution was increased to as much as 25 mL per kilogram of body weight when LV hypertrophy was severe. The initial dose was standardized by LV mass and ranged from 1.0 to 3.6 ml/gm (average, 2.7 ml/gm). Postoperative peak levels of the myocardial-specific isoenzyme of creatine phosphokinase (CPK-MB) showed no significant relationship to aortic cross-clamp time, but were related significantly to LV mass (r = 0.457, p less than 0.02). The initial dose of cardioplegic solution per LV mass and the peak CPK-MB had an inverse relationship (r = -0.753, p less than 0.001). Also, peak CPK-MB was significantly lower in those patients with an initial dose of cardioplegic solution per LV mass of 2.5 ml/gm or more regardless of the size of the LV mass (300 gm or more and less than 300 gm) in spite of no significant difference in myocardial temperature. These results indicate that the dose determination of cardioplegic solution by LV mass seems desirable for patients with chronic aortic valve disease and LV hypertrophy even when myocardial temperature is monitored.     

A case report of tetralogy of Fallot associated with total occlusion of the right coronary artery and complicated with infective endocarditis]

A 31-year-old male with tetralogy of Fallot (TF) and total occlusion of the right coronary orifice complicated with infective endocarditis successfully underwent total repair of TF and coronary artery bypass graft (CABG). The patient had severely suffered from symptoms including breathlessness, palpitation (SVT) and chest pain. The coronary arteriography revealed occlusion of the right coronary orifice. The preoperative course was further complicated by endocarditis with vegetation of the aortic valve that did not respond to antibiotics. Concomitant surgical procedures consisting of TF repair, CABG to the right coronary artery with saphenous vein graft and vegetectomy of the aortic valve were carried out. The postoperative course was uneventful though he underwent cholecystectomy for symptomatic gall stones after TF repair. The patient is now in NYHA class II.     

A case report of Rastelli operation in 2-month-old infant with truncus arteriosus (type II)

A two-month-old girl with heart failure from truncus arteriosus (Collett & Edwards Type II) underwent a total correction by the Rastelli procedure using 12-mm-diameter Hancock valved conduit. The orifice of pulmonary arteries was closed from inside without detachment of the pulmonary artery from truncus. The distal anastomosis of the conduit was made to left pulmonary artery. Primary sternal closure was difficult and delayed closure was performed using splint with a resin plate. The skin was primarily closed using bilateral advancement myocutaneous flaps. Complete closure of the sternum was made on the 11th postoperative day. A rotation flap of the right abdominal rectal muscle was used to cover the partially necrotic skin over the sternum. The patient had persistent respiratory and cardiac problems, but was discharged 14 months after surgery.