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Seventeen patients treated for infected grafts (11/17) or aneurysms (6/17) of the aorta between 1998 and 2003 were reviewed to evaluate our experience with aortic infection. The causative organisms were identified in 12 patients (71%), with 5 (29%) having methicillin-resistant Staphylococcus aureus. A periaortic abscess occurred in eight patients, and all of them were associated with infected grafts. Surgical treatment included cryopreserved allograft replacement in eight patients, prosthetic graft replacement in four patients, and drainage with or without omental wrapping in five patients. One patient was still hospitalized at the end of the study period. Five patients with infected grafts died after the operation during the initial hospitalization. No early mortality occurred in the aneurysm group. The early mortality rate was 31% for all patients, 50% for the graft group, and 63% for patients with a periaortie abscess. Another patient with an infected aneurysm died of arrhythmia after discharge from the initial hospitalization, Ten patients are still alive without evidence of reinfection. The early mortality rate for patients with infected aortic grafts is higher than that for those with infected aneurysms, especially when a periaortic abscess accompanies them. However, the late outcome is favorable, with no reinfection or late treatment-related deaths.

A 54-year-old woman, who underwent descendo-abdominal aortic bypass grafting for atypical aortic coarctation complicated with Takayasu’s arteritis 37 years previously, was referred to our hospital for treatment of a pseudoaneurysm due to rupture of the graft. Preoperative computed tomography scan also demonstrated an abdominal aortic aneurysm. First, an endovascular stent-graft repair of the pseudoaneurysm was performed, then the abdominal aortic aneurysm was repaired with the aid of cardio-pulmonary bypass. Proper surgical planning was important to treat this rare development accompanied by aberrant circulation.

This study evaluates the effectiveness and potential complications of stent-grafting for the treatment of distal arch aneurysms using profound hypothermia and circulatory arrest with retrograde cerebral perfusion. Between December 1998 and December 2001, 9 consecutive patients with a distal arch aneurysm (6 men and 3 women, mean age 71 years) underwent surgical repair using a stent-graft. Profound hypothermic circulatory arrest and retrograde cerebral perfusion were performed in all patients. Endovascular leakage was screened postoperatively using three-dimensional computerized tomography. The mean follow-up period was 27.4 months. Thirty day mortality was 0%. One patient died 3 months after stent-grafting due to proximal leakage into her aneurysm. The mean postoperative extubation period was 2.1 days. No patients suffered cerebral infarction or paraplegia. Although preliminary outcomes using this technique were good, endovascular leakage is a concern. We suggest that, if major proximal leakage is recognized postoperatively, re-intervention should be performed as soon as possible. Endovascular stent-grafting appears to be a good alternative treatment for distal arch aneurysms, although longer follow-up is necessary to more comprehensively evaluate this procedure.

Background— We assessed the feasibility of beating atrial septal defect (ASD) closure monitored by real-time 3D echocardiography (RT3DE). Methods and Results— RT3DE was developed with prototype ultrasound equipment consisting of a high-speed 3D rendering unit with a frame rate of 5 to 10 frames/s. We also developed a prototype semiautomatic suture device and suture cutting system. In the experiment, 12 mongrel dogs were anesthetized, and after median sternotomy, the echo probe was applied directly to the surface of the right atrium. Three surgical maneuvers (balloon atrial septectomy, enlargement of the ASD, and ASD closure) were performed through the atrial port inserted into the right atrial appendage. The heart was then excised, and the area of the ASD measured by RT3DE was compared with its area measured directly. The ASD was successfully closed in all experimental animals except the first 2. Examination of the excised heart showed that none of the sutures were loose. The mean area of the ASD was 82.5±38.6 mm 2 when measured by RT3DE and 81.6±38.2 mm 2 when measured directly, and there was a significant correlation between the areas measured by RT3DE and those measured directly (echo measurements=1.007×direct measurements+0.337; P 2 upper and −6.024 mm 2 lower limit of agreement). Conclusions— Introduction of RT3DE, a semiautomatic suture device, and a suture cutting system made beating ASD closure without cardiopulmonary bypass possible.

The purposes of this study were to develop ultrathin-wall grafts suitable for stent-graft procedures and to examine the feasibility of the grafts from the physical point of view. We fabricated ultrathin-wall grafts with a wall thickness of 42 to 137 μm, using 50 denier polyester threads consisting of 72 polyester monofilaments. We studied the following physical properties of the ultrathin wall: the surface structure of the grafts, the longitudinal tensile strength of the grafts, the water permeability of the grafts, and the size of introducers through which the stent grafts can pass. In ultrathin-wall grafts with a wall thickness of 75 μm or more, a regular surface structure with zero planimetric porosity was recognized. In those with a thickness less than 64 μm, the porosity increased as the wall thickness decreased. The longitudinal tensile strengths of the 75 μm and 64 μm grafts were 13.1 ± 0.9 and 9.5 ± 0.9 kg, respectively. The water permeability of the 75-μm grafts was 380 ml/min, and that of the thinner grafts increased as the wall thickness decreased. Stents with a diameter of 40 mm covered with the ultrathin-wall grafts could pass through introducers with an inner diameter of 18 French. We conclude that the newly developed ultrathin-wall grafts are physiologically suitable for endovascular surgery.

1240 The Journal of Thoracic and Cardiovascular Surgery • December 2001 O pen surgery with an endovascular stent graft is a novel therapeutic technique for aortic aneurysm that is especially useful for aneurysms of the distal arch. In this report we describe the clinical course and autopsy findings of 2 patients who had paraplegia after undergoing this procedure and died during the hospital stay.

Objectives: Many interventional physiological assessments for retrograde cerebral perfusion (RCP) have been explored. However, the appropriate arterial gas management of carbon dioxide (CO 2 ) remains controversial. The aim of this study is to determine whether alpha-stat or pH-stat could be used for effective brain protection under RCP in terms of cortical cerebral blood flow (CBF), cerebral metabolic rate for oxygen (CMRO 2 ) and distribution of regional cerebral blood flow. Methods: Fifteen anesthetized dogs (25.1 ± 1.1 kg) on cardiopulmonary bypass (CPB) were cooled to 18°C under alpha-stat management and had RCP for 90 min under: (1), alpha-stat; (2), pH-stat: or (3), deep hypothermic (18°C) antegrade CPB (antegrade). RCP flow was regulated for a sagittal sinus pressure of around 25 mmHg. CBF was monitored by a laser tissue flowmeter. Serial analyses of blood gas were made. The regional cerebral blood flow was measured with colored microspheres before discontinuation of RCP. CBF and CMRO 2 were evaluated as the percentage of the baseline level (%CBF, %CMRO 2 ). Results: The oxygen content of arterial inflow and oxygen extraction was not significantly different between the RCP groups. The %CBF and %CMRO 2 were significantly higher for pH-stat RCP than for alpha-stat RCP. The regional cerebral blood flow, measured with colored microspheres, tended to be higher for pH-stat RCP than for alpha-stat RCP, at every site in the brain. Irrespective of CO 2 management, regional differences were not significant among any site in the brain. Conclusions: CO 2 management is crucial for brain protection under deep hypothermic RCP. This study revealed that pH-stat was considered to be better than alpha-stat in terms of CBF and oxygen metabolism in the brain. The regional blood flow distribution was considered to be unchanged irrespective of CO 2 management.

Objective: The purpose of this study is to evaluate the possibility of identifying critical segmental arteries (CSAs) based on Doppler ultrasonographic hemodynamics. Methods: In 18 mongrel dogs, the descending aorta was scanned directly with a 5-MHz linear probe through left thoracotomies and the flow velocities in segmental arteries were measured by pulsed Doppler. The aorta was cross-clamped between Th13 and L1, and flow velocity changes were recorded. According to flow increases, segmental arteries were divided into three groups: arteries with the largest flow increase (L-arteries), arteries with the smallest increase (S-arteries) and other arteries (O-arteries). Animals were divided into three groups. One aortic segment including an L-artery or an S-artery was perfused via a temporary shunt during 30-min aortic cross-clamping distal to the left subclavian artery (Group L or Group S) and neurological outcomes were compared with those of animals without shunting (Group N) after 24 and 48 h. Results: L-arteries had significantly larger flow increases than S- and O-arteries (74.3 ^ 33.8, 20.4 ^ 9.8 and 33.3 ^ 17.8 cm/s, P , 0.01). In Group N, five of the six animals were completely paraplegic (Tarlov Grade 0) and the other was Grade 1. In Group S, four animals were Grade 4 and two were Grade 0 after 24 h. However, two animals showed delayed paraplegia. Therefore, four animals were Grade 0 and two were Grade 4 after 48 h. All animals in Group L were neurologically normal (Grade 4) at both after 24 h (vs. Group N, Pa 0:0013) and 48 h (vs. Group N, Pa 0:0013; vs. Group S, Pa 0:019). Conclusions: Flow responses to aortic cross-clamping differed among segmental arteries and selective perfusion of L-arteries completely prevented paraplegia. Therefore, L-arteries were considered to be CSAs. Hemodynamic measurement of segmental arterial flow using Doppler ultrasonography could be clinically useful for spinal cord protection during thoracoabdominal aortic surgery. q 2001 Elsevier Science B.V. All rights reserved.

Objective: We evaluated effects of type, size, and orientation of mechanical mitral valve prostheses on hemolysis.Methods: Subjects were 84 patients who had undergone mitral valve replacement. Lactate dehydrogenase was mainly used as a marker of hemolysis and was measured before surgery, 1 month after surgery, and in the late postoperative period.Results: Valves used included 16 Medtronic-Hall, 32 St. Jude Medical, and 36 CarboMedics valves. Medtronic-Hall valves caused less hemolysis than St. Jude Medical or CarboMedics valves in the late postoperative period. This resulted because hemolysis due to Medtronic-Hall valves was more severe 1 month after surgery than in the late postoperative period and because hemolysis due to St. Jude Medical or CarboMedics valves was more severe in the late postoperative period than 1 month after surgery. One reason for this finding is that cardiac output was greater in the late postoperative period than 1 month after surgery, making regurgitation through the pivots of bileaflet valves more severe. The orifice area and the orientation of prostheses did not affect hemolysis.Conclusion: St. Jude Medical or CarboMedics valves caused more severe hemolysis than Medtronic-Hall valves in the late postoperative period.

Background: Visualization of the left circumflex arteries during off-pump coronary artery bypass grafting (CABG) causes hemodynamic disturbance. We investigated whether right heart mini-pump bypass (RHB), using a centrifugal pump, improved the safety of this procedure by studying the influences of different heart displacement positions, the Trendelenburg maneuver and RHB on hemodynamics. Method: Hemodynamic parameters in eight mongrel dogs (15.5‐20 kg) were continuously monitored at a fixed heart rate of 80 beats/min through a conventional median sternotomy. The posterior descending artery (PDA) and left circumflex artery (LCX) were exposed using an Octopus tissue stabilizer. After evaluating the influence of the Trendelenburg maneuver on hemodynamics, a heparin-coated centrifugal pump without an oxygenator was introduced and the impact of different pump flow volumes was investigated during RHB. Results: LCX exposure caused significant decreases in aortic flow (to 35.1 ^ 12.8%) and arterial mean pressure (to 66.1 ^ 9.3%) compared with baseline (P , 0:001). In contrast to PDA exposure, values remained significantly decreased during the Trendelenburg maneuver. On the contrary, RHB significantly improved the hemodynamic impairments caused by both heart displacement procedures, especially LCX exposure, although 100% pump flow significantly increased left atrial pressure to 131.3 ^ 19.5% (P , 0:01). Conclusion: Exposure of the LCX caused severe hemodynamic deterioration, which was not fully reversed by the Trendelenburg maneuver. In contrast, RHB significantly improved hemodynamics, and therefore this technique can be beneficial for CABG of LCX in the limited cases. q 2000 Elsevier Science B.V. All rights reserved.

Displacement of the heart to expose the left circumflex artery (LCX) causes hemodynamic disturbance during off-pump coronary artery bypass grafting (CABG). We applied right heart bypass (RHB) using a heparin-coated centrifugal pump without an oxygenator in an attempt to stabilize the hemodynamics. Five mongrel dogs (15.5-20 kg) were used. Hemodynamic parameters were continuously monitored at a fixed rate of 80 beats/min. The LCX was exposed with the use of an Octopus Tissue Stabilizer. After baseline data were obtained, each dog was placed in the Trendelenburg position. Finally, RHB was established with different pump flows. LCX exposure caused a significant decrease in aortic flow (to 33.1% +/- 13.1% of the baseline value) and arterial mean pressure (to 68.3% +/- 8.5%) (P0.001). Trendelenburg positioning caused these values to recover to 57.1% +/- 6.7% and 72.5% +/- 7.7%, respectively. RHB with 50% flow significantly improved the hemodynamic values, although 100% flow significantly increased LAP by 134.8% +/- 19.7% (P0.01). Tilting of the canine heart to expose the LCX caused significant deterioration of the hemodynamic values. Trendelenburg positioning was moderately effective, and RHB very effective, in improving the hemodynamics. In a limited number of cases, an appropriate flow of RHB may provide safe hemodynamic assistance during off-pump CABG of the LCX.

The Harmonic Scalpel (HS; Ethicon Endo-Surgery, Cincinnati, OH, USA) is an ultrasonic coagulator that generates less heat than electrocautery. We compared canine internal mammary arteries (IMAs) harvested using the HS or electrocautery and reviewed the early clinical outcome after thoracoscopic IMA takedown with the HS. Using HS and bipolar electrocautery (BE), 51 and 49 IMA branches, respectively, in six mongrel dogs were divided. The divided branches were subjected to a pressure tolerance test. The impact of coagulation on the main trunk was investigated microscopically. Thoracoscopic IMA harvesting with the HS was performed in 41 patients. Seven human IMA segments including 10 branches were examined microscopically. Postoperative angiography of 40 IMA grafts (97.6%) was performed. All the IMA branches withstood intraluminal pressures up to 250 mmHg. With BE, coagulation reached the adventitia of the main trunk in six segments (12.2%), but the HS caused no injury. Thoracoscopic IMA harvesting with excellent hemostasis was achieved using only the HS in all 41 patients. The main trunks of the human IMA segments were microscopically intact, and postoperative angiography demonstrated that the IMA grafts were intact. The HS appears to be a reliable coagulator for thoracoscopic IMA harvesting with minimal damage.

Background . The hemodynamic effects of carbon dioxide insufflation under single-lung ventilation were studied in 22 consecutive thoracoscopic harvests of the left internal mammary artery, which was used for minimally invasive coronary artery bypass grafting. Methods . An electrocardiograph, arterial catheter, Swan-Ganz catheter, and transesophageal echocardiograph were used to monitor seven hemodynamic variables. Baseline data were obtained during ventilation of both lungs and the measurements were repeated after the left lung was collapsed and at 5 and 30 minutes after hemithorax insufflation with low-flow (2 to 3 L/minute) carbon dioxide gas was begun. The intrapleural pressure was maintained at 8 to 10 mm Hg. Results . Thoracoscopic harvest of the internal mammary artery was completed in all cases with a mean insufflation time of 44 ± 12 minutes. There were no significant changes in the mean arterial pressure, heart rate, cardiac index, and left ventricular ejection fraction throughout the procedure, whereas the central venous pressure, mean pulmonary arterial pressure, and pulmonary capillary wedge pressure ( p Conclusions . Low-flow carbon dioxide insufflation into the left hemithorax with an intrapleural pressure of 8 to 10 mm Hg under selective right-lung ventilation does not compromise the human heart with normal to moderately depressed function and can be an efficacious adjunct in specific thoracoscopic procedures.

Background . Paravalvular leakage is one of the most serious complications of aortic valve replacement in patients with aortitis syndrome. The purpose of this study was to compare the effectiveness of the intravalvular implantation technique in preventing paravalvular leakage with that of the conventional technique. Methods . Since 1982, 14 patients with aortic regurgitation caused by aortitis syndrome have undergone aortic valve replacement at our institute. An intravalvular implantation technique was applied in 7 of the 14 patients. The technique consists of suturing a prosthetic valve to the aortic annulus and sandwiching the leaflets between exogenous felt pledgets and the inflamed aortic annulus. Results . Paravalvular leakage occurred in 3 of 7 patients in the conventionally treated group and in none of 7 in the intravalvular implantation group. Conclusions . The intravalvular implantation technique is effective in preventing paravalvular leakage in patients with aortitis syndrome.

Background . The purpose of this study was to develop a method of atrial ablation. In the IRK-151 infrared coagulator, light from a tungsten-halogen lamp is focused into a quartz rod. The distal exit plane is connected to a tip made of sapphire to allow linear ablation. Methods . Thirty-six lesions were created in 9 mongrel dogs. The beating ventricular myocardium was ablated from the epicardium. In each dog, 4 lesions were created by using the following durations of application: 3, 9, 15, and 21 seconds. After the ablation, the myocardium was fixed and stained. A linear lesion on the beating right atrial free wall was created. Before and after the ablation, epicardial plaque–electrode mapping was performed. Three months after ablation, remapping was performed. Results . The ablated myocardium had well-demarcated necrosis without carbonization or vaporization. The maximum depth was 10.3 ± 0.8 mm. The conducting pathway was blocked. The block, once made, continued for 3 months. Conclusions . The IRK-151 produces well-demarcated lesions that were deep enough for atrial ablation to block the conducting pathway.

A 69-year-old female with advanced right mammary carcinoma presented to us with diffuse stenosis of the proxymal left anterior descending artery (LAD). Right mastectomy had been suspended. The LAD was treated with minimally invasive CABG (MICABG) assisted with a thoracoscopic procedure. The left internal thoracic artery (LITA) was taken down through thoracoscopy from the upper margin of the 1st rib to the lower margin of the 5th rib using only the Harmonic Scalpel (Ethicon Endo-Surgery). Coronary anastomosis to the LAD was completed without cardiopulmonary bypass through a small thoracotomy on the anterior 4th intercostal space. The operation time was 4 h 30 min and the blood loss was 120 ml. Post operative course was uneventful. Doppler study and angiography demonstrated patent LITA to the LAD. Right mastectomy was achieved 29 days after MICABG. MICABG can be a veneficial alternative method for the patient with malignant disease, allowing quick convalescence and early cancer operation. Thoracoscopy allows for sufficient LITA harvest up to the 1st rib or higher with the Harmonic Scalpel.

We report a rare case of hemolysis after coil occlusion of a patent ductus arteriosus (PDA), which was treated by surgical removal of the coil and closure of PDA. A 65-year-old woman was admitted to our hospital with congestive heart failure due to severe aortic regurgitation associated with PDA. Before undergoing open heart surgery she underwent closure of the PDA using a Jackson coil as an adjunct of treatment to improve her hemodynamic state. However, a small residual shunt resulted in severe hemolysis. Two weeks after the intervention she underwent aortic valve replacement and PDA closure after removal of the coil through the main pulmonary artery under moderate hypothermia and temporary circulatory arrest. Hemolysis is always secondary to a residual leak and several methods have been reported to manage this complication. Our report suggests that early surgical retrieval of the coil before the organized thrombus is formed, can be safely performed even in an elderly patient whose ductus is usually fragile.

Objective: The transseptal superior approach can offer an excellent view of the mitral valve but the incision almost always transects the sinus node artery. The purpose of this study was to evaluate the sinus node function after mitral operation by this approach. Patients and Methods: We reviewed the electrocardiograms of 76 patients who underwent mitral valve operations either via transseptal superior approach or via right lateral atriotomy. Nine patients who maintained the sinus rhythm for more than one year after surgery via the transseptal superior approach were selected for electrophysiological study to evaluate the sinus node function. Results and Conclusions: Postoperative electrocardiographic and electrophysiological studies revealed that the sinus node function after the transseptal superior approach was relatively well maintained for more than one year after the operation. The influence of the transseptal superior approach on the sinus node function in the mid-term postoperative period was apparently mild and did not cause a serious problem. However, some of the patients did show abnormal data in terms of sino-atrial conduction time and intrinsic heart rate. Therefore, further follow-up of the sinus node function is necessary in patients who underwent mitral surgery through the transseptal superior approach.

We recently performed mitral valve repair for a case of mitral regurgitation due to Barlow's disease, which is relatively rare in Japan. Both the anterior and posterior leaflets were affected by advanced myxomatous change, and appeared markedly thickened and redundant. Although extensive resection of the anterior leaflet is not a generally accepted method, nearly one fourth of the anterior leaflet was resected in this case. Now, at 36 months after the operation, there is only trivial regurgitation and the patient is doing well and without symptoms. We believe that extensive resection of the anterior leaflet can be a useful treatment for repair of a redundant anterior leaflet with excess tissue.

雑種成犬を用いて心外膜側から連続的ないし経時的にHis束電位を記録する方法を実験的に研究した.ます心外膜側からマッピングを行いHis束電位の記録可能部位は, 右心房と大動脈根部との境界であるaorto-atrial grooveを中心とする領域であることを同定した.続いて安定した記録のために針電極を自家作成し, 記録可能部位の2ケ所に刺入し双極誘導で記録した.この電極刺入点は実験犬のホルマリン固定した心臓標本の刺激伝導系を剖出して検討することにより決定した.さらに従来のカテーテル電極による心腔内電位記録を対照として, 心房頻数刺激法と心房早期刺激法を行い, A-HおよびH-V時間の変化を検討することにより, 心外膜側から記録されたspike電位をHis東電位と同定した.本研究によるHis東電位記録法は, 記録部位の指標を示すことで, より普遍化され簡便な記録法として基礎的, 臨床的応用も可能と考えられた.

Open-heart surgery has been performed since 1975 on 25 patients who are Jehovah's Witnesses by religion. The patients' ages ranged from 6–60 years, and their body weights from 18–51 kg. Surgical procedures included correction of congenital heart disease in 14 patients and valve repair or replacement in 11. Six procedures were reoperations. The lowest mean haematocrits, during perfusion and the postoperative period, were 22.7% (range 15.0–31.0%) and 27% (range 16.0–36.0%), respectively. Twenty-four patients survived and are alive and well. One patient died of low output failure before discharge. The blood return system reduced blood loss. Five of the patients who underwent cardiac surgery received recombinant erythropoietin before and after surgery, leading to higher postoperative haematocrits. In one patient, a haematocrit which fell to 16.9% after surgery was raised to 27% by administration of erythropoietin, without blood transfusion. In two recent cases, high doses of aprotinin were used during surgery, resulting in better haemostasis after cardiopulmonary bypass.

An 87-year-old woman who had undergone a stent-graft repair of a descending aortic aneurysm had additional stent-graft implantation for endoleak. The postoperative course was eventful reflecting her preexisting multiple organ disorder, and despite intensive treatment over a span of 2 months, she died of disseminated intravascular coagulation due to intestinal ischemia. Autopsy revealed a thrombus originating from the frayed distal edge of the graft. Although the relation between intestinal ischemia and the thrombus remains to be proven, this is considered a vital finding.

Twenty-five cases of intracardiac tumors were operated upon from 1975 through 1994. Twenty-four operative survivors were followed up. The follow-up period ranged from 2 months to 19 years with an average of 8 years. The histological diagnoses of the tumors were as follows: benign tumors 21 (myxoma 20, leiomyoma 1) and malignant tumors 4 (sarcoma 3, carcinoma 1). In 21 cases, tumors had cardiac origins, while there were four intracardiac tumors which had originated in other organs and extended transvenously to the intracardiac cavity (leiomyoma 1, sarcoma 2, carcinoma 1). The results of surgical treatment of intracardiac benign tumors were satisfactory, regardless of their origins and multiplicity, both in the short-term and in the long-term. On the other hand, the long term results for malignant intracardiac tumors were extremely poor, although their excision or resection had a beneficial effect on the hemodynamics in patients with congestive heart failure or cardiogenic shock.

教室では complicated PDAに対し, 補助手段として体外循環 (ECC) を積極的に用いて手術を行ってきた. ECC下に手術を行った complicated PDAの10症例を対象としてECCを用いた理由, 術式, 手術成績, 術後在院期間などについて検討を行った. ECCを用いた症例の年齢は平均46±17歳と高齢で, ECCを用いた理由は重複例を含み高齢8例, 動脈管の硬化・石灰化7例, window 様動脈管5例, 右側下行大動脈1例, 動脈管動脈瘤2例, 結紮術後再開通1例であった. 2例では正中アプローチ, 他の8例では左開胸アプローチ (F-Fバイパス) で手術を行い, 動脈管の石灰化の程度や動脈管動脈瘤の有無によって, 種々の術式を選択した. 術後の在院日数はECC非使用例に比べやや長かったが, 手術死亡・入院死亡ともになく, 満足しうる結果であった. Complicated PDAに対する手術では安全性を最も重視すべきであり, ECCを積極的に利用することは手術の安全性向上に有用であった.

We report an unusual case of aortobronchial fistula late after transverse arch replacement caused by the remnant of a temporary bypass near the ascending aorta. In reconstructive surgery of the ascending aorta, antegrade perfusion is preferably performed through a side branch after completion of the distal anastomosis by some surgeons. This report suggests possible risk of a serious late complication unless the side branch is placed and tailored properly.

The approach to the heart for open heart surgery in patients with a tracheostoma requires careful consideration. The presence of a tracheostoma interferes with the standard sternotomy and increases the risk of mediastinitis. We have successfully performed coronary artery bypass grafting in two patients with a tracheostoma using the limited median sternotomy and describe the surgical procedure used in these patients.

Endovascular covered stents were successfully applied to temporarily halt hemoptysis and postpone surgical intervention in a 69-year-old man with a ruptured anastomotic false aneurysm of the distal aortic arch. Surgical graft implantation was performed successfully by the elephant trunk technique 14 days after the endovascular stent-grafting, at which time aspiration pneumonia had subsided.

Thoracic and abdominal aortic aneurysms have potential risk of sudden death, because they have a tendency of rupture. The risk of rupture is high, if they are saccular type or the diameters of them are large enough. Acute aortic dissection has a high risk of sudden death due to cardiac tamponade, if the dissection involves the ascending aorta.

Objective: The efficacy of acute normovolemic hemodilution (ANH) in avoiding homologous blood transfusion (HBT) during cardiovascular surgery remains controversial. Our objective was to evaluate the impact of ANH on blood transfusion requirements during open cardiovascular surgery using cardiopulmonary bypass (CPB). Methods: We retrospectively reviewed 243 patients who had undergone open cardiac or thoracic aortic surgery using CPB between September 2001 and July 2003 in our department. ANH was performed when the hematocrit was over 35% and the patient was hemodynamically stable. Risk factors were selected in accordance with the Japanese Adult Cardiovascular Surgery Database and analyzed to determine their effect on perioperative HBT requirement. Results: Of the 243 patients, 64 (26%) underwent preoperative autologous blood donation and 62 (26%) ANH. HBT was required in 62% of patients (150/243) overall, in 32% (20/62) of ANH patients, and in 76% (130/171) of non-ANH patients. Multivariate stepwise logistic regression analysis revealed that preoperative or pre-donation hemoglobin value (p

Objective: Retrograde cerebral perfusion (RCP) is used as an adjunctive method to hypothermic circulatory arrest to enhance cerebral protection in patients undergoing thoracic aortic surgery. It remains unclear whether RCP provides improved neurological and neuropsychological outcome. Methods: Forty-six patients undergoing thoracic aortic surgery using RCP, and 28 undergoing coronary artery bypass grafting (CABG; nZ28) with CPB, were enrolled in the study. Patients receiving RCP were subdivided into two groups, those with less than 60 min of RCP (S-RCP; nZ27) and with 60 min or more (L-RCP; nZ19). The patients’ neurocognitive state was assessed by the revised Wechsler Adult Intelligence Scale a few days before operation, at 2–3 weeks and 4–6 months after operation. Results: There were no stroke, seizure, and hospital mortality in either group. Significant decline between baseline and early scores were seen in three subtests (digit span, arithmetic, and picture completion) for S-RCP and four (digit span, arithmetic, picture completion, and picture arrangement) for L-RCP. Significant decline between baseline and late scores were seen in one subtest (arithmetic) for S-RCP, four (digit span, arithmetic, picture completion, and picture arrangement) for L-RCP, and one (object assembly) for CABG. The mean change of scores for one late test (digit symbol) was significantly lower in S-RCP than in CABG. The mean change of scores for three early tests (digit span, vocabulary, and picture arrangement) and four late tests (information, digit span, picture completion, and picture arrangement) were significantly lower in L-RCP than in CABG. Stepwise logistic regression analysis disclosed that, after considering the other variables, significant difference in test score changes were observed between CABG and L-RCP for two early tests (picture completion and digit symbol) as well as for three late tests (digit span, similarities, and picture completion). None of test score changes showed significant difference between CABG and S-RCP. Conclusions: The neurocognitive outcome in patients undergoing RCP less than 60 min were comparable with patients undergoing CABG without circulatory arrest. Prolonged RCP of 60 min or more in patients undergoing surgery of the thoracic aorta was associated with postoperative neurocognitive impairment.

前胸部痛・ショックを主訴とした34歳男性に対しAAEおよび急性大動脈解離破裂の診断にて緊急手術を行った. 解離は大動脈基部に限局し, 右冠状動脈はほぼ全周に近く解離が及んでいたが, 末梢側には離断を認めなかったため冠状動脈入口部の再建を行った. 手術は composite graft を用いて大動脈基部置換術を行ったが, 冠状動脈口の吻合に際して独自の工夫を加え冠血行再建をより確実なものとした. 急性解離における冠血行再建法を中心に, 今回のわれわれの方法について文献的考察を加え報告する.

Clinical Summary A 52-year-old man had undergone, in another hospital, a graft replacement of the ascending aorta and coronary bypass grafting (saphenous vein to the right coronary artery) for acute type A aortic dissection. Gelatin-resorcinol-formaldehyde tissue glue had been used in reinforcement of the dissected aorta in both ends. Nine months after that operation, the patient had dyspnea and mild fever. Computed tomographic (CT) scan showed pseudoaneurysm of the ascending aorta, and he was referred to us. Physical findings included a continuous murmur maximal at the second right intercostal space. Chest radiography showed mild cardiomegaly and enhancement of the right pulmonary vasculature. Transesophageal echocardiography and a new CT scan (Figure 1) revealed a pseudoaneurysm of the ascending aorta, with fistulization to the right pulmonary artery arising from the proximal anastomosis. Aortography confirmed complete occlusion of the vein graft as well as the presence of the aortopulmonary fistula. Right heart catheterization revealed right-sided pressure elevation. When the left ventricular pressure was 74/20 mm Hg, the right atrial pressure was 17 mm Hg, the right ventricular was 34/18 mm Hg, and the pulmonary arterial pressure was 35/16 mm Hg. An oxygen saturation step-up was observed in the pulmonary artery, with 59.8% in the main pulmonary artery and 91.8% in the right pulmonary artery. Because of the risks of repeated median sternotomy, we chose a right thoracotomy to approach the aortic root. We prepared a cryopreserved aortic valve allograft in case of infection. The right fourth intercostal space was opened, and sternal transection and left thoracotomy were included. The femoral artery and the superior and inferior venae cavae were cannulated for cardiopulmonary bypass. An occlusion balloon was inserted into the distal part of the pseudoaneurysm to reduce the degree of aortopulmonary shunting. After systemic cooling, retrograde cardioplegia, and deep hypothermic circulatory arrest, the pseudoaneurysm was incised, and dissection proceeded until the distal part of the aortic graft was crossclamped and systemic circulation was resumed. The defect of the right pulmonary artery wall was 14 mm in diameter; it was closed with the anterior mitral leaflet taken from the aortic allograft. We found dehiscence in the anterior part of the proximal anastomosis, blackened aortic edge, and fragile aortic wall with dissection almost reaching the annulus. There were no findings indicating infection. The left coronary ostium was resected as a button. A Dacron polyester fabric tube composite graft with a mechanical valve was inserted into the aortic root, and the left coronary button was reattached to the graft. During rewarming, the right internal thoracic artery was anastomosed to the right coronary artery (Figure 2). The patient’s postoperative course included pneumonia, which improved with antibiotics, and he was discharged 47 days after operation. Histologic examination of the media of the dissected aorta revealed a homogeneous eosinophilic substance that seemed to be composed of glue, severe calcification, and fibrous tissue with hemosiderin deposition.

This report describes a 60-year-old male patient who developed early valvular obliteration of a cryopreserved aortic valve allograft with associated severe valvular leakage. The patient had previously undergone two operations for aortic valve insufficiency resulting from infective endocarditis, and prosthetic valve endocarditis: aortic valve replacement with a mechanical prosthesis was done 4 years ago, and two years later aortic root replacement with a cryopreserved allograft was performed. Perforation through the non-coronary cusp of the aortic allograft was found, and valve replacement was achieved using a mechanical prosthesis. The intraoperative findings, histological, immunological, and bacteriological studies of the resected cusps demonstrated negative for infection and rejection, therefore, the valvular perforation might have been caused by an injury or degeneration during management of the homologous graft. The patient showed neither aortic regurgitation on echocardiography nor recurrence of endocarditis 10 months after surgery.

We report a case of left coronary artery ostial stenosis and bilateral pulmonary artery (PA) stenosis in a 22-year-old woman with Wegener granulomatosis (WG). Complicating periaortitis and obstruction of the internal thoracic arteries hampered conventional coronary artery bypass grafting and in situ PA reconstruction. Successful treatment was achieved by restoration of right ventricular outflow tract (RVOT) to bilateral PA continuities with reinforced polytetrafluoroethylene (PTFE) grafts and coronary-coronary bypass.

We report a case of ruptured aortic aneurysm of the distal aortic arch. This aneurysm was fusiform and only 4.0 cm in maximum diameter: Emergency total aortic arch replacement was successful. Rupture of a thoracic aortic aneurysm of this shape and size is possible but extremely rare.

Since Haissagere and colleagues [1] reported that a rapid firing focus in or close to the pulmonary veins could be the cause of atrial fibrillation, a transcutaneous catheter technique directed at isolating these foci has been developed. How should patients with nonvalvular atrial fibrillation who require cardiac operation be managed? We developed an epicardial technique that uses cryoablation to isolate the left atrial posterior wall and pulmonary veins and used it to treat a patient. Because cryoablation is achieved epicardially, the technique does not require atriotomy and does not prolong aortic cross-clamp time. Isolation of the left atrium was confirmed by electrophyscologic studies, and the patient remains in sinus rhythm 16 months after operation. This concomitant procedure allows treatment of patients with nonvalvular atrial fibrillation.

Left atrial dissection, a rare complication occurring mainly after mitral repair, is reported after double valve replacement in a patient with a connective tissue disease. A 63-year-old woman with systemic sclerosis underwent double valve replacement. Laceration of the tissue between the two mechanical prostheses and dissection of the left atrial wall emerged postoperatively and regurgitation through the dissection caused heart failure, which later improved without surgery. The possible causes of the dissection were thought to be shear forces against the tissue between the two prostheses and tissue fragility due to systemic sclerosis and corticosteroid therapy.

Seven patients with malignant cardiac tumors were treated surgically in the Department of Cardiothoracic Surgery of the University of Tokyo between 1981 and 2000. Their treatments and outcomes are summarized and discussed. The ages of the patients ranged from 21 to 70 years old (mean: 49.5+/-15) and there were three males and four females. The histopathological diagnoses were hepatocellular carcinoma (HCC), spindle cell sarcoma, round cell sarcoma, osteosarcoma, renal cell carcinoma, and leiomyosarcoma. In four of the cases, the tumor extended or metastasized from other organs, while in the other three cases it originated in the heart. Before the cardiac operation, an above-knee amputation, left nephrectomy, transarterial embolization, or extended right hepatic lobectomy had been performed to treat the primary site of the tumor. Tumor resection using cardiopulmonary bypass was performed in every case. The NYHA classification of heart failure was significantly improved (preop: 3.3+/-0.8, postop: 1.9+/-0.7 [P

The aim of this study was to determine whether alpha- or pH-stat protects the brain during deep hypothermic retrograde cerebral perfusion. Fifteen anesthetized dogs on cardiopulmonary bypass were cooled to 18°C under alpha-stat and underwent retrograde cerebral perfusion for 90 minutes under alpha-stat or pH-stat, or underwent antegrade cardiopulmonary bypass under alpha-stat as the control. Cerebral blood flow of the cortex was monitored and serial analyses of blood gases and total nitric oxide oxidation products made. Cerebral blood flow and cerebral metabolic rate for oxygen were significantly higher and plasma levels of nitric oxide oxidation products in the outflow from the brain were significantly lower in retrograde cerebral perfusion under pH-stat than under alpha-stat. This study shows that reduced levels of nitric oxide oxidation products may protect against neuronal damage induced by nitric oxide and that increased cerebral blood flow under pH-stat may lead to a reduction of nitric oxide oxidation products. Under retrograde cerebral perfusion, pH-stat is thus better than alpha-stat for protecting the brain.

A 74-year-old man with an aortic arch aneurysm and a chronic type IIIb aortic dissection underwent total aortic arch repair without cerebral or cardiac ischemia. After confirming no atheromatous change in the ascending aortic wall, a custom-designed 4-limbed graft, prepared for both arterial return of cardiopulmonary bypass and reconstruction of the arch vessels, was anastomosed onto the right side of the ascending aorta. The 3 arch vessels were then bypassed sequentially during systemic cooling and monitoring cerebral perfusion with near-infrared oxymetry. After aortic cross-clamping, a stent graft was inserted into the distal arch from the distal ascending aorta, maintaining cerebral and cardiac perfusion. This procedure is indicated especially in a high-risk patient who has an aortic arch aneurysm without severe atheromatous change in the ascending aorta and the arch vessels.

This report describes a male patient with WPW syndrome who underwent surgical repair of sudden, severe mitral valve regurgitation through the posterior leaflet 20 months after successful RF catheter ablation for Kent bundle at the age of 14, and discusses the problem of valvular damage caused by this technique.

Open surgery using the endovascular stent-graft is a novel technique that lessens the invasiveness of surgery for the aortic arch. However, the outcome of this procedure remains uncertain.Between November 1996 and July 2000, a total of 19 patients underwent open surgery using an endovascular stent-graft for thoracic aortic aneurysms. There were 15 men (78.9%) and 4 women (21.1%). Patient age ranged from 29 to 82 years (mean 69.3 years, median 74 years). Atherosclerotic thoracic aortic aneurysms were present in 17 patients (89.4%) and aortic dissection in 2 patients (10.5%).Two patients (10.5%) died in the hospital and 4 patients (21.1%) presented with paraplegia postoperatively. Among the 4 patients with postoperative paraplegia, 1 case was complicated with intraoperative aortic dissection. The other 3 patients with paraplegia had spinal cord ischemic time of more than 60 minutes and intraoperative body weight gain of more than 4 kg. Of these 3 patients, hemodynamic instability after cardiopulmonary bypass was observed in 1 patient and cholesterin embolus in the anterior spinal artery was found at autopsy in another. On univariate analysis, age greater than 75 years was the only risk factor associated with paraplegia (p0.05). Autopsy findings for the 2 patients showed that the Adamkiewicz arteries were not blocked by the stent-graft in either patient.Intraoperative aortic dissection, embolization of the intercostal arteries, long ischemic time of the spinal cord, and excessive weight gain during operation may have been associated with the high incidence of paraplegia after open surgery using the endovascular stent-graft.

Conventional graft replacement of the ascending aorta and surgically endovascular stent-grafting of the proximal descending aorta were performed concomitantly in a 82-year-old woman with an acute DeBakey type II aortic dissection and a chronic DeBakey type IIIb aortic dissection. Postoperative computed tomography and angiography showed the adequately replaced ascending-aortic prosthesis, the well-expanded stent-graft, and the thrombosed false lumen in the descending aorta.

The short-term results after aortic root replacement with 11 cryopreserved aortic homografts was examined. Since 1998, the University of Tokyo Tissue Bank has supplied 11 aortic homograft valves. Nine of the recipients were male, and the average age was 51.2 years. Nine out of 11 patients had suffered from a serious condition of native or prosthetic valve infectious endocarditis. All of the patients underwent aortic root replacement, and the blood type between the patient and the homograft was matched in 8 of the patients. Only 1 patient died (9.1%) in the short-term due to sepsis. The preoperative degree of aortic valve regurgitation in all of the cases was third or fourth while the regurgitation disappeared after the operation in all of them. Thinking of the serious condition of our cases preoperatively, the 9.1% operative mortality was quite acceptable. Long-term follow-up is necessary to estimate the quality of the homografts.

Background . The effectiveness of blood conservation measures for thoracic aortic operations with deep hypothermic circulatory arrest has not yet been documented. Methods . From July 1997 to December 2000, 148 thoracic aortic operations were performed in our department. Sixty-one cases involving patients who underwent elective thoracic aortic operation with deep hypothermic circulatory arrest were reviewed retrospectively. Results . Seventeen patients did not meet the criteria for the blood conservation program and were excluded from the present study. Therefore, 44 patients were analyzed in this study. Overall, 50% of patients did not require operative homologous blood transfusion (HBT) and 43% did not require in-hospital HBT. Smaller amounts of autologous donation, greater blood loss, and a longer operation time were independent risk factors for HBT requirement. Among 16 patients who had made an autologous donation of 1,600 mL or greater, 75% did not require intraoperative HBT and 69% did not require in-hospital HBT. The overall perioperative mortality rate was 4.5%. As for postoperative complications, prolonged intubation and postoperative infection were significantly more frequent among patients who required in-hospital HBT. Conclusions . Our combined blood conservation measures were effective in avoiding HBT during major thoracic aortic operations with deep hypothermic circulatory arrest and may have reduced postoperative complications. The amount of the autologous donation was a strong predictor for avoiding HBT.

Atrial and ventricular dysrhythmias developing after cardiac operation further reduce cardiac output, posing a serious problem for postoperative management. We have developed a "bio-mini-paddle" electrode designed to be attached directly to the myocardium for atrial or ventricular defibrillation and pacing for intraoperative and postoperative cardiac management. We use fibrin glue for the paddle, which is biodegradable. The characteristics of this unique paddle were examined using mongrel dogs.

Objectives: We have conducted aortic valve-sparing operation for patients having aortic root dilatation and almost normal aortic valve leaflets since August 1998, and here report midterm results.Methods: Patients with dilated aortic annulus or Marfan’s syndrome were treated with reimplantation, and the remaining patients with remodeling. Either 24 or 26 mm graft was selected based on aortic annular diameter and leaflet size. Aortic valve competence was assessed regularly with echocardiography.Results: Five patients (age: 29±13 yr), including 4 with Marfan’s syndrome, had undergone reimplantation, and 3 (age: 46±18 yr) remodeling by December 2000. Mean follow-up was 18 (range: 10–32) months, and no postoperative death has occurred and no reintervention has been required thus far. All the patients in the remodeling group showed only a small pressure gradient through the aortic valve and decreased left ventricular diameter. Two in the reimplantation group showed a pressure gradient exceeding 20 mmHg. Two Marfan’s syndrome patients in the reimplantation group showed slightly increased diastolic left ventricular diameter and 3 slightly increased systolic left ventricular diameter. Although aortic regurgitation had diminished in all patients by discharge, moderate aortic regurgitation recurred in 1 non-Marfan’s syndrome patient in the reimplantation group because of degenerated aortic valve.Conclusion: Although postoperative aortic valve function was not perfect in all patients undergoing reimplantation, midterm results after aortic valve-sparing operation were generally satisfactory. Proper selection of patients, procedures, and graft size was thought to be important to ensure a favorable surgical outcome.