A Case of Spontaneous Ascending Aortic Rupture Which Was Difficult to Distinguish from Stanford Type A Acute Aortic Dissection / 日本心臓血管外科学会雑誌

A 77-year-old man was admitted to our hospital with sudden anterior chest pain followed by shock. An echocardiography showed enlargement of the sinus of Valsalva, severe aortic regurgitation and pericardial effusion. A chest CT scan showed a crescent sign in the ascending aorta. The preoperative diagnosis was a ruptured Stanford type A acute aortic dissection and an emergency operation was performed. In the operative findings, a bloody pericardial effusion, a hematoma around the ascending aorta and a tear (less than 2 cm) of the ascending aorta just distal area of the sinotubular junction were observed. In this case, since the enlargement of the sinus of Valsalva and the severe aortic regurgitation were observed, we performed a replacement of the ascending aorta including the aortic root with an artificial vascular graft (J graft 28 mm) and a biological valve (Magna EASE 25 mm). The pathologic examinations revealed a rupture of ascending aorta in all layers and a hematoma outside the adventitia. The pathologic diagnosis showed a spontaneous aortic rupture. The postoperative course was good and he was discharged 1 month after the surgery. A spontaneous aortic rupture is defined as an aortic rupture without a trauma, an aneurysm or a dissection. It is rare but fatal and it is said that surgical treatment is necessary. We report a successful surgical case of the spontaneous aortic rupture which was difficult to distinguish from a Stanford A type acute aortic dissection.

A Case of Tricuspid Leaflet Augmentation for Severe Secondary Tricuspid Regurgitation / 日本心臓血管外科学会雑誌

A 71-year old woman, who underwent direct closure of an atrial septal defect with mild tricuspid regurgitation (TR) 18 years previously, suffered terminal cardiac failure with extreme cardiomegaly, mitral regurgitation and severe TR. Medical treatment gradually became ineffectual and we decided to perform surgical therapy. Mitral annuloplasty with a prosthetic ring, tricuspid valve repair, plications of extended bilateral atrium walls and epicardial ventricular pacemaker implantation were performed. In tricuspid valve repair, anterior tricuspid leaflet was augmented by use of glutaraldehyde-preserved autologus pericardial patch and tricuspid annuloplasty with addition of a slightly larger prosthetic ring. Atrio-ventricular regurgitations disappeared and she was discharged 63 days after the operation. Valve extension is a very effective technique to treat severe secondary TR, and long term follow-up is necessary.

Surgical Treatment of Pulmonary Artery Aneurysm Thirty-Eight Years after an Operation for Atrial Septal Defect / 日本心臓血管外科学会雑誌

Pulmonary artery aneurysm (PAA) may be associated with congenital shunt disease such as patent ductus arteriosus, and its frequency and management are often controversial. We report successful surgical treatment of PAA following an operation for atrial septal defect (ASD). The patient was a 47-year-old woman who underwent closure of ASD at the age of 9. When she was investigated because of thyroid tumor, enlargement of her main pulmonary artery was pointed out and she was admitted to our hospital. Several examinations revealed a diagnosis of pulmonary valve insufficiency and 70mm PAA with dilatation extending to both proximal arteries. We performed replacements of pulmonary valve and pulmonary artery with a bioprosthetic valve and T-shaped graft. The patient is doing well 2 years after operation.

Long-Term Results after Prosthetic Bypass Surgery for Chronic Limb Ischemia / 日本心臓血管外科学会雑誌

We evaluated long-term results of 126 consecutive bypass surgeries for chronic limb ischemia including 54 aorto-femoral (AF), 26 femoro-femoral crossover (FF), 7 axillo-femoral (AxF), and 39 femoro-above the knee popliteal (FP) bypasses. Patients who had undergone FF bypasses were significantly older than those who received AF bypasses (<i>p</i><0.01). Preoperative ankle brachial pressure indices (ABI) of the AxF and FF patients were significantly lower than those of AF patients (<i>p</i><0.05). Compared with AF patients, the AxF and FF groups included significantly higher percentages of Fontaine III and IV limbs treated by limb salvage surgery (<i>p</i><0.05). The cumulative graft patency rates 5 years after AF, FF, and FP bypasses were 94.7%, 91.3%, and 64.3%, respectively. In the FP group, patients with intermittent claudication before surgery showed a 5-year graft patency rate of 82.5%, while that in patients who underwent surgery for limb salvage was 43.3%. The secondary graft patency rates 5 years after AF, FF, and FP bypasses were 94.6%, 91.3%, and 83.3%, respectively. All patients whose bypass grafts were occluded were male and were smokers. Poor run-off and insufficient anticoagulation therapies were also associated with graft occlusion. Two of the 12 patients who developed graft occlusion underwent limb amputation.

A Case of Aortic Root Remodeling for Aneurysm of the Noncoronary Sinus of Valsalva / 日本心臓血管外科学会雑誌

We report a case of aneurysm localized to the noncoronary sinus of Valsalva with moderate aortic regurgitation (AR). The patient was a 49-year-old woman who had been suspected to have some kind of connective tissue disorders. She underwent an aortic root remodeling procedure to replace the isolated, unruptured and extracardiac aneurysm and the ascending aorta. Postoperative angiogram showed no aneurysm and improved AR. This procedure was able to preserve her own aortic valve and normal sinuses of Valsalva and enable her to obtain better quality of life, although progression of the enlargement of the aorta or AR requires careful follow-up.

The Effects of Rewarming Speed on Cerebral Circulation and Oxygen Metabolism during the Rewarming Period of Cardiopulmonary Bypass / 日本心臓血管外科学会雑誌

We investigated the effects of rewarming speed on cerebral circulation and oxygen metabolism during cardiopulmonary bypass (CPB). Twenty-four adult patients who had undergone open heart surgery with moderately hypothermic CPB were divided into two groups. In the slow rewarming group (group S), the rates of increase of blood temperature were under 0.1°C/min. In the rapid rewarming group (group R), they were more than 0.1°C/min. Mean blood flow velocity in the middle cerebral artery (mean MCAv) was measured by transcranial Doppler ultrasonography, and the index of cerebral oxygen consumption was evaluated by Doppler-estimated cerebral metabolic rate for oxygen (D-CMRO₂). The change of oxyhemoglobin level in the brain (Oxy Hb) was monitored by near-infrared spectroscopy. In group S, mean MCAv and D-CMRO₂ changed in a parallel manner following the changes of the rectal temperature throughout the periods, and mean MCAv was always higher than D-CMRO₂. In group R, however, the rate of increase of D-CMRO₂ was more rapid than that in group S from the beginning of rewarming, and D-CMRO₂ exceeded the level of mean MCAv just before termination of CPB. In addition, Oxy Hb in group R showed more rapid changes than that of group S. In conclusion, rapid rewarming during CPB may cause the disruption of cerebral flow-metabolism coupling.

A Case of Emergency Surgery for Ruptured Descending Thoracic Aortic Aneurysm into the Left Lung in an Elderly Patient / 日本心臓血管外科学会雑誌

We report an 85-year-old woman with rupture of aneurysm of the descending thoracic aorta into the left lung. She was admitted with sudden onset back pain and hemoptysis. Emergency operation was performed to replace the ruptured descending thoracic aorta, and lower lobectomy of left lung. The left lobectomy ensured that hematoma was not left in lung, although it decreased respiratory function after operation. In addition, it decreased bleeding and operating time compared to segmental resection. She was discharged without contracting an infection in the lung or graft, although she needed tracheotomy for a time. We suggest that the lower lobectomy of lung was an important factor in saving this elderly patient with rupture of an aneurysm into the left lung.

Evaluation by Students of Bedside Learning in the Department of Pediatric Surgery / 医学教育

We evaluated bedside learning in the department of pediatric surgery by conducting a questionnaire survey of senior medical students at Chiba University School of Medicine. We obtained responses from 70 of 95 students (74%). Although 84% of students responded by making lists of patients' problems. Many students indicated insufficient knowledge about diseases and insufficient technical skills for medical treatment as the reasons they could not solve these problems. This finding indicates that students do not have sufficient basic knowledge and clinical skills for bedside learning. These skills must be acquired and evaluated before bedside learning can be started.

Two Cases of Acute Aortic Dissection after Y Graft Repair of the Abdominal Aortic Aneurysm / 日本心臓血管外科学会雑誌

We experienced two rare cases of acute aortic dissection with leg ischemia after Y graft repair of the abdominal aortic aneurysma. Case 1 was a 63-year-old woman who had received Y graft repair at age 55, and case 2 was a 28-year-old man with Marfan's syndrome who received a Y graft repair at age 21. Both patients sustained DeBakey type I dissections terminating at the suture line of the Y graft and had symptoms of acute arterial occlusion of bilateral lower extremities. Emergency operation was performed 8 hours after onset in case 1 and 6 hours after in case 2. Case 1 could not be weaned from cardiopulmonary bypass because of intraoperative rupture and acute heart failure, but case 2 underwent successfully aortic root replacement and total arch replacement under selective cerebral perfusion.

A Case of Localized Pericarditis Associated with Organized Hematoma / 日本心臓血管外科学会雑誌

A 64-year-old man with a history of anterior blunt trauma 10 years previously was admitted to our hospital complaining of general fatigue. A plain chest roentgenogram showed pericardial calcification. Computed tomography and echocardiography showed the mass to be a calcified capsule in the anterior mediastinum compressing the right side of the heart. He underwent an operation through a median sternotomy. The mass was an organized hematoma encapsulated by a calcified fibrous and serous layer of the pericardium. The hematoma was resected together with the calcified pericardium under cardiopulmonary bypass. His postoperative course was uneventful. He had no history of hemopericardium but had experienced blunt chest trauma that seemed to have induced the subsequent localized constrictive pericarditis.

Response of Cerebral Blood Flow and Metabolism to Changes in Arterial Carbon Dioxide Tension during Moderate Hypothermic Cardiopulmonary Bypass in Patients with Cerebrovascular Disease / 日本心臓血管外科学会雑誌

The purpose of this study was to examine the responses of cerebral blood flow and metabolism to changes in arterial carbon dioxide tension during moderate hypothermic cardiopulmonary bypass in patients with cerebrovascular disease undergoing open heart surgery. Computed tomography scan (CT) and single photon emission computed tomography (SPECT) were performed preoperatively for 17 patients. The patients were categorized according to their CT and SPECT findings. Ten patients were included in the normal group, 7 patients were included in the CVD group. Blood flow velocity in the middle cerebral artery (MCAv) was measured by means of transcranial Doppler ultrasonography at two different arterial carbon dioxide tensions (at a high PaCO₂ of 45-50mmHg, at a low PaCO₂ of 30-35mmHg, uncorrected for body temperature) during moderate steady-state hypothermic cardiopulmonary bypass. Simultaneously cerebral oxygen consumption was estimated by relating the arteriovenous oxygen content difference to flow velocity (D-CMRO₂). MCAv and D-CMRO₂ were expressed as percentages of the values determined at 30 minutes before cardiopulmonary bypass. In the normal group, a PaCO₂ of 47.4±2.5mmHg (mean±SD) was associated with an MCAv of 99.4±17.8% and a D-CMRO₂ of 53.4±25.5%, while a PaCO₂ of 33.7±1.3mmHg was associated with an MCAv of 64.3±18.1% and a D-CMRO₂ of 53.5±26.2%. In the CVD group, a PaCO₂ of 49.1±4.2mmHg was associated with an MCAv of 81.4±22.3% and a D-CMRO₂ of 34.0±19.4%, while a PaCO₂ of 33.6±1.3mmHg was associated with an MCAv of 54.7±23.8% and a D-CMRO₂ of 49.0±19.4%. We conclude that in patients with cerebrovascular disease cerebral blood flow is changed in response to changes in arterial dioxide tension during moderate hypothermic cardiopulmonary bypass, however a high PaCO₂ depresses cerebral oxygen consumption because hypercarbia may cause potentially harmful redistribution of regional cerebral blood flow away from marginally-perfused to otherwise well-perfused areas.

Aortic Dissection Associated with Atherosclerotic Aortic Aneurysm / 日本心臓血管外科学会雑誌

Between January 1980 and September 1993, 7(8.4%) of 83 patients with aortic dissection had coincident atherosclerotic true aneurysms of thoracic and/or abdominal aorta or had undergone operation of true aortic aneurysms. There was no difference in the segments of aortic dissection; 4 of 50 patinets classified as DeBakey III and 3 of 33 patients classified as DeBakey I or II, whereas the site of atherosclerotic true aneurysms was more often in the abdominal aorta than in the thoracic aorta. Five patients had undergone surgery for or had the abdominal aortic aneurysms and 2 patients had thoracic aortic aneurysms. In 2 patients who had previously undergone abdominal aortic aneurysmectomy, the dissected aorta ruptured soon after the onset of dissection. In the patients in whom the true aneurysm and the aortic dissection involve the same segments surgical treatment would be extended and complex.

Open Heart Surgery Using a Centrifugal Pump in a Patient Suffering from Hereditary Spherocytosis / 日本心臓血管外科学会雑誌

A very rare case of open heart surgery associated with hereditary spherocytosis (HS) is reported. A 10-year-old girl was admitted for repair of an atrial septal defect (ASD). She was found to have HS by the microscopic findings of a blood smear and characteristic osmotic fragility, but splenectomy had not been undertaken preoperatively. She underwent successful radical operation by means of a centrifugal pump, and poloxamer 188 and haptoglobin were used during cardiopulmonary bypass for prevention of hemolysis. No significant hemolysis occurred intra- or postoperatively. Cardioplumonary bypass using a centrifugal pump appeared to be effective in this patient with HS.

Complications and Prognoses of Patients Treated for Stanford Type B Aortic Dissection / 日本心臓血管外科学会雑誌

In the past 11 years, we treated 41 patients with Stanford type B aortic dissection. Principally, medical therapy was carried out and surgery was performed only when complications related to the dissection occurred. Twenty two patients (53.7%) had complications, including 5 (12%) with peripheral limb ischemia, 3 (7%) with rupture, 13 (32%) with dilatation of the aorta, 4 (10%) with extension of dissection (type A dissection). Seventeen patients received surgery including palliative operation. Among 41 patients, 3 died due to aortic rupture and 2 died at surgery for type A dissection, while 4 of them had developed proximal extension of the dissection. The 5-year survival rate for all patients was 86.7±6.6%. Long term survival will improve in patients with Stanford type B aortic dissection when the operative mortality for type A dissection is reduced and sound management policies are developed.

Study of operation results for acute aorta dissociation of DeBakey I tape.Replacement technique of the ascending aorta by an artificial blood vessel / 日本心臓血管外科学会雑誌

From January of 1987 to December 1992, twelve patients (7 males and 5 females, mean age, 52.8 years) underwent emergency surgery for DeBakey type I acute aortic dissection. The surgical procedure was resection of the initial intimal tear and replacement of the ascending aorta (four patients underwent hemiarch replacement). Operative mortality was 41.7% (5/12). Three died in the operating room due to heart failure (2) and uncontrollable bleeding (1). Another two early deaths resulted from extension of the residual false lumen. All surviving patients each had a patent double-channeled aorta and aneurysmal dilatation of the false lumen was noted in 3 patients. There were two late deaths, one due to rupture of the residual false lumen and the other, to stroke during re-operation for enlargement of the residual false lumen. It is apparent from these results that in type I acute aortic dissection extensive operation such as total arch replacement is necessary.

PLSVC as a Pitfall of Retrograde Cardioplegia / 日本心臓血管外科学会雑誌

Retrograde cardioplegia is now an alternative or adjunctive method used worldwide as a cardiac protection during open heart surgery. However, its use involves some limitation. We operated on a patient suffering from aortic stenosis associated with PLSVC. During the operation on this patient for aortic valve replacement, retrograde infusion of cardioplegic solution could not be performed because the coronary sinus was excessively dilated and prevented the balloon from occluding it. Other anomalous lesion of the coronary sinus make the retrograde infusion of the cardioplegic solution difficult and these must always be kept in mind when cardioplegia is infused from the coronary sinus.

Myocardial Revascularization Combined with Valvular Surgery / 日本心臓血管外科学会雑誌

Myocardial revascularization combined with valvular surgery were performed on 8 patients between 1986 and 1990. There were 4 males and 4 females (mean age=60.6 years). Mitral valve replacement was performed in 3 patients, aortic valve replacement in 2, and double valve replacement in 3. There were no operation death, but one late death was seen. No angina attack was evident and NYHA functional class was improved in all patients in survivers. Coronary angiography should be performed in all adult patients who have valvular disease and those with significant artery disease should undergo bypass grafting concomitant with valvular surgery.