Importance of early repair of isolated abdominal aortic dissecting aneurysm.

BACKGROUND: Since the available information on isolated abdominal aortic dissecting aneurysm (AADA) is mainly related to case reports or reports of small groups of patients, its natural history remains undetermined and there is no agreement on its optimal management. The purpose of this study is to define the features and pattern of development of this unusual entity as well as to propose criteria for treatment based on our own experience and previously published data. PATIENTS AND METHODS: We retrospectively evaluated the history of 6 patients diagnosed with AADA. The patients were 5 males and 1 female. The mean age was 71 +/- 8 years (range: 61-80 years), and the mean aneurysm diameter was 54 +/- 14 mm (range: 35-70 mm). All of these patients were hypertensive (100%). History of cerebrovascular accident, ischemic heart disease, peripheral arterial disease, or diabetes mellitus was present in 1 patient, respectively. Two patients developed mycotic AADA. RESULTS: Emergency operations had been performed in 3 cases, and scheduled surgical reconstruction in the remaining 3 cases. Operation consisted of aneurysmectomy and graft replacement of the diseased aortic segment in all cases. One patient treated in an emergency setting died subsequently of multisystem organ failure, but the others did well. CONCLUSION: Symptomatic patients or patients at good risk should undergo surgical repair earlier than in the case of abdominal aortic aneurysm without dissection (AAA). Dissection in addition to an AAA will further increase the weakness of the aortic wall and the possibility of aortic rupture will become higher.

Contribution of the bronchial circulation to lung preservation.

Short preservation time still severely limits lung transplantation. To determine the effect of bronchial arterial flush preservation, we studied 54 dogs using the isolated perfused working lung model. After baseline measurements, lungs were flushed with lactated Ringer's solution (60 ml/kg at 8 degrees C) by one of three methods: pulmonary artery perfusion, bronchial artery perfusion through a 15 cm closed aortic segment, or simultaneous pulmonary-bronchial artery perfusion. These groups were further subdivided and tested after 0, 4, and 17 hours of storage at 4 degrees C (n = 6 each). Lungs were ventilated (flow rate 140 ml/kg/min; inspired oxygen fraction 0.21) and continuously reperfused with normothermic deoxygenated autologous blood in a closed loop. Measured variables were hemodynamics, aerodynamics, and leukocytes in bronchoalveolar lavage. Survival time was determined from initial reperfusion to failure of the lung to oxygenate. After 0 and 4 hours of storage, there was no significant difference in survival times. After 17 hours, lungs subjected to pulmonary-bronchial artery perfusion survived longer than those perfused via either the pulmonary or bronchial arteries alone (120 +/- 24 versus 38 +/- 14 or 52 +/- 16 minutes; p less than 0.01). Pulmonary artery pressure and resistance in all groups except at failure were never different from baseline values in the intact animal. Shunts in the pulmonary-bronchial artery perfusion groups were closest to baseline at onset (8% +/- 4%) and remained lower throughout reperfusion than in the groups subjected to pulmonary or bronchial artery perfusion alone. After 17 hours, static compliance of pulmonary artery-perfused lungs was worse than baseline (1.1 +/- 0.2 x 10(-2) versus 3.2 +/- 0.7 x 10(-2) L/cm H2O/sec; p less than 0.05), whereas compliance in the pulmonary-bronchial artery perfusion groups remained constant (3.6 +/- 1.5 x 10(-2) L/cm H2O/sec). Elastic work performed by lungs subjected to pulmonary-bronchial artery flushing at onset was significantly lower when these lungs were reperfused immediately (201 +/- 14 versus 295 +/- 35 gm-m/min for pulmonary artery-flushed lungs) or after 4 hours of storage (229 +/- 30 versus 290 +/- 24 gm-m/min for pulmonary artery-flushed lungs). Bronchoalveolar lavage after 17 hours in the group subjected to pulmonary bronchial artery flushing demonstrated leukocyte counts similar to those of intact lungs (45 +/- 5 versus 29 +/- 8/mm3) and significantly less than in lungs subjected to pulmonary or bronchial artery flushing (137 +/- 18 or 82 +/- 10/mm3, respectively).(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of desmopressin acetate on hemorrhage without identifiable cause in coronary bypass patients.

After early hopeful reports, the ability of desmopressin acetate (DDAVP) to substantially reduce post surgical hemorrhage has been questioned. A total of 74 elective coronary bypass patients (Group A) receiving DDAVP (0.3 micrograms/kg) who, in the opinion of the operating surgeon, did not achieve adequate hemostasis after protamine neutralization of heparin were studied. They were compared with 91 age- and sex-matched controls (Group B). Before surgery there was no difference in hematocrit (40.8% vs. 40.3%); bleeding time (5.3 vs. 4.9 sec); platelet count (267 +/- 8 vs. 309 +/- 13 X 10(3)/mm3); fibrinogen (363 vs. 361 mg/dl); or activated clotting time (ACT) (168 +/- 4 vs. 163 +/- 3 sec). Both groups had the same number of grafts (3.3/pt), use of the mammary artery (72%), and average bypass time (124 min). There were also no differences in postbypass ACT (142 +/- 3 vs. 135 +/- 2 sec); platelet count (97 +/- 10 vs. 120 +/- 24 X 10(3)/mm3); and fibrinogen (157 +/- 35 vs. 207 +/- 40 mg/dl). However, postoperative hemorrhage was strikingly different: 1306 +/- 89 vs. 896 +/- 33 ml (P less than .0001). Fifteen patients in Group A bled more than 1.5 liters compared with 4 in Group B. Red cell transfusion rates were 1.23 +/- 0.26 for Group A and 0.35 +/- 0.8 for Group B (P less than 0.005). Sixteen Group A patients received additional blood products (plasma and platelets). The hemorrhage difference remained significant even when these patients were excluded (1098 +/- 57 vs. 896 +/- 34, P less than 0.003). Three Group A patients were re-explored without a bleeding source located.(ABSTRACT TRUNCATED AT 250 WORDS)

Resection of hepatoblastoma with right atrial extension using cardiopulmonary bypass.

A 3-year-old boy underwent a successful combined resection of a hepatoblastoma and its intracaval right atrial extension using a cardiopulmonary bypass. This type of extension is extremely rare in hepatoblastoma. The cardiopulmonary bypass enabled complete resection of the intracardiac mass of the hepatoblastoma. In addition, dissection and ligation of the right hepatic vein under cardiopulmonary bypass made the following right hepatectomy easy and safe.

Mitral valve replacement and subsequent composite graft replacement of the aortic root for infantile Marfan syndrome.

The cardiovascular lesions commonly seen in Marfan syndrome can frequently be the primary cause of premature death. Cardiac lesions involving both the mitral valve and the aortic root are commonly observed among patients diagnosed during early infancy, as so-called infantile Marfan syndrome. Since the lesions tend to progress rapidly with the end results of high morbidity and mortality, the majority of patients require surgical intervention at a young age. However, patients who undergo surgical intervention for both lesions during the first decade of life have been rarely reported in literature. In this report, we present a case of a 9-year-old boy who underwent aortic root replacement with a composite graft at 3.5 years after a prior prosthetic valve replacement of the mitral valve. Although the immediate result was satisfactory, the long-term result remains to be seen.

[The changes of the methods of the right ventricle outflow tract reconstruction].

There are many situation that we need to do some procedure for the right ventricle outflow tract reconstruction (RVOTR) among the congenital heart diseases. The procedures have changed during past decade. Also the changes have shown about the materials for outflow patches. We reviewed the changes through our experience. There were seventy-six cases or RVOTR from August, 1988 to December, 2000. Most of them were tetralogy of Fallot. Fifteen cases were done the Rastelli procedure. There were some other congenital heart diseases. The materials were mainly artificial in the period before 1995. Then it has been changed mainly to the autologous pericardium in the period after 1996. The sizes of the tract were made to match the standard of Rowlatt. We found some re-stenosis and late mortality because of the pulmonary valve regurgitation. We are trying to reduce such complications.

[Surgery for the valvular disease in children].

We report the results and long-term follow up in 34 children (17 girls and 17 boys, aged 12 days to 13 years, average age 3.3 years, average body weight 11.7 kg) who underwent valvular surgery in the period between May 1989 and November 1996. Operative mortality was 11.8%. Actuarial survival curves (including hospital mortality) indicate a 68.6% survival rate at 5 years and that 64.7% of patients are free from reoperation at 5 years. For aortic regurgitation two patients applied aortic valvuloplasty and four applied aortic valve replacement. Nine children had aortic stenosis, three of them had balloon valvuloplasty, seven had valvotomy, two had aortic valve replacement. Ten patients were treated for mitral regurgitation. There were nine valvuloplasty and four mitral valve replacement including three times of reoperation. One membranous pulmonary atresia and seven pulmonary stenosis children had valvotomy. There were four cases of tricuspid disease. One had tricuspid valve stenosis with pulmonary stenosis, three had severe tricuspid regurgitation who applied tricuspid valve replacement. Mortality was high in the critical AS, severe MR and TVR groups. Patients who survived the surgery and had no complications showed satisfiable results.

[Experience with a operated cervico-mediastinal neuroblastoma in infant].

Cervical neuroblastoma is relatively rare and shows very good prognosis. We reported a case of surgically resected cervico-mediastinal neuroblastoma. A 7-month-old boy was pointed out to have Horner syndrome (right ptosis and anhidrosis) and an abnormal shadow at right cervico-mediastinum on chest X-ray film during his stay in another hospital because of acute bronchitis. On examination after admission in our hospital, 3 x 4 cm size mass was palpated at the right neck and urine VMA and HVA level were elevated. The close examination demonstrated no sign of tumor in any other organ and tissue, which suggested that the tumor was cervical origin. 9 x 5, 5 x 3 cm tumor was almost removed and patient received chemotherapy. He is now free from disease at 1 year after operation.

[A case of ascending aortic aneurysm with intrathoracic goiter].

A case of the successful operation for ascending aortic aneurysm and intrathoracic goiter was described. A 71-year-old woman was admitted to our hospital for the treatment of ascending aortic aneurysm disclosed by the examination in another hospital. Preoperative chest CT showed ascending aortic aneurysm as large as 8 cm in diameter, and an upper mediastinal tumor compressing the main bronchus. The tumor was continuous with the right lobe of the thyroid. The excision of the tumor was performed through median sternotomy with cervical collar incison. After that, the replacement of the ascending aorta was carried out under cardiopulmonary bypass and hypothermic circulatory arrest. The histological examination of the resected specimen revealed adenomatous goiter without malignancy.

[A case of mitral valve replacement and left atrial plication for infantile Marfan syndrome with giant left atrium due to mitral valve regurgitation].

In Marfan syndrome, there is a subset, called infantile Marfan syndrome, in which the disease is diagnosed during infancy and cardiac lesions including mitral regurgitation and aortic root dilatation tend to be deteriorated rapidly. In infantile Marfan syndrome, respiratory function is sometimes impaired when skeletal abnormalities such as scoliosis and pectus excavatum are severe. In this report, we describe a 2-year and 4-months old boy with infantile Marfan syndrome who presented with severe mitral regurgitation and the collapsed left lung. In addition to the impairment of respiratory function due to severe scoliosis, the left lung was collapsed because of the compression of the left bronchus by the enlarged left atrium. The patient required mitral valve replacement concomitantly with left atrial plication, resulting in the decompression of the left bronchus and the re-expansion of the left lung. Characteristics and surgical management of infantile Marfan syndrome are discussed in this report.

[Emergency coronary artery bypass grafting with integrated myocardial protection].

In the following retrospective study we reviewed the early postoperative results of emergency CABG; the myocardial management was achieved by utilization of integrated myocardial protection including warm cardioplegic induction, performed at our hospital. From April 1st 1994 to October 30th 1998; 63 patients underwent emergency CABG with integrated myocardial protection. All surgical procedures were performed within 6 hours from the onset of disease or admission transferred from another hospitals. Age ranged 48 to 86 years (mean 69.9 +/- 8.5; 41 male, 22 female). AMI was present in 52, UAP in 11. Preoperative PTCA was done in 20 and IABP was inserted in 53. Cardiogenic shock in 26, mechanical complications in 6, three vessel disease in 48 and LMT disease in 17 was present. Eight patients (12.7%) died in the early postoperative period. Among evaluated risk factors for early postoperative death; the occurrence of cardiogenic shock, mechanical complications of AMI, preoperatively done PTCA and prolonged CPB time were significantly increasing the mortality rate in early postoperative death.

[Immunochemotherapy of resectable lung cancer--a preliminary study on a comparison of the control, levamisole, and OK-432].

We conducted a prospectively controlled study of adjuvant immunochemotherapy for resectable lung cancer in 37 cases of the control group, in 34 cases of levamisole group and in 40 cases of OK-432 group. No significant difference was noted in patient characteristics of age, sex, histological type, stage, cure rate, etc. The survival rates were calculated by Kaplan and Meier method. Survival curves were measured by generalized Wilcoxon test and Cox-Mantel test. When the levamisole group and the control group were compared in terms of survival rate, a significant increase of survival curves of patients treated with levamisole was observed in surgicopathological stage III + IV and relative curative operation groups (p less than 0.05). The survival rate of levamisole group was higher than that of OK-432 group in patients of surgicopathological stage III and III + IV (p less than 0.05). There was no statistically significant difference between OK-432 group and the control group, when in survival rates.

[Clinical study of serum enzyme and metabolic changes after extracorporeal circulation--comparison with the surgery of aortic aneurysm].

The changes of serum enzyme and metabolism were studied by comparing the serial change among three groups. The first group consisted of twenty seven patients treated by surgery under extracorporeal circulation. The second group of ten patients of thoracic aortic aneurysm treated under temporary bypass and the third group of nineteen patients of abdominal aortic aneurysm under aortic cross clamp. The following results were obtained: The enzyme of serum GOT, LDH and CPK increased postoperatively in the all groups, the changes after surgery being greater in the group 1 than the other groups. The metabolism of lactic acid and glycolipid was depressed in the group 1 higher than the other groups. The tissue injury of total body after surgery with extracorporeal circulation was greater than the other groups without extracorporeal circulation. And these results suggest the necessary of improvement of circuit and perfusion technique of extracorporeal circulation.

[Closing aortic dissection--it's clinical manifestation and treatment].

15 cases (31.6%) with closing aortic dissection have been experienced among 46 cases in acute dissecting aneurysm of the aorta during past 8 years and 9 months. Ulcer like projection was recognized in 81.8% of closing aortic dissection. Serum FDP level measured within 48 hours after onset was significantly lower and serum fibrinogen level was significantly higher in closing aortic dissection than in patent false lumen type. Especially, the case with FDP < or = 10 micrograms/ml, fibrinogen > or = 300 mg/dl is strongly suspected as closing aortic dissection. There was no death among patients with closing aortic dissection except one who died after operation at chronic phase. These patients were well controlled by medical therapy except one who received emergent operation. We showed 3 interesting cases with Stanford A type closing aortic dissection. One patient was treated surgically because of cardiac tamponade and shock, but the other two patients were treated medically. From these results, we conclude that medical therapy should be a first choice for patients with closing aortic dissection regardless of Stanford classification.

[Clinical study on measurement of cerebral metabolism and oxygenation during cardio-pulmonary bypass by near-infrared spectrophotometry].

We studied the non-invasive method of monitoring of cerebral metabolism and oxygenation of patients mainly with thoracic aortic aneurysm during Cardio-pulmonary bypass (CPB) by Near-infrared Spectrophotometry (NIRS) to establish the safety limits of cerebral perfusion. NIRS monitoring of all 12 patients showed that cerebral oxygenation levels were maintained within the pre-CPB range when mean arterial perfusion pressure (MAPP) was above 60 mmHg. With considering rectal temperature, the cerebral oxygenation levels were maintained above the pre-perfusion baseline when MAPP was above 50 mmHg at rectal temp. < or = 25 degrees C, and 73 mmHg at > or = 25 degrees C. It was suspected that cerebral autoregulatory mechanism could exist even in hypothermia (< or = 25 degrees C) because cerebral oxy-Hb and blood volume was significantly declined when MAPP was reduced to 40 mmHg or less. In 5 patients who underwent selective cerebral perfusion, the base line level of blood volume was preserved when the perfusion flow rates were above 0.5l/min, and the desirable oxy-Hb levels were obtained when the flow rates were above 0.4l/min. During deep hypothermic circulatory arrest (18 degrees C), cerebral oxy-Hb level was gradually reduced from baseline, reflecting proceeding metabolic activity even in profound hypothermia. These findings led us to conclude that non-invasive, continuous, and direct monitoring of cerebral oxygenation using NIRS can provide valuable data to prevent cerebral injury after CPB. It is hoped that the safety limits of cerebral perfusion and circulatory arrest can be established in the future using multiple analysis of pressure, flow, temperature, Hb concentration and so far by NIRS.

Endoscopic thoracic sympathectomy: evaluation of pulsatile laser, non-pulsatile laser, and radiofrequency-generated thermocoagulation.

We describe a modified technique for percutaneous denervation of the thoracic sympathetic chain by laser to treat selected cases of sympathetic causalgia of the upper extremities. The technique involves transpleural ablation with laser under thoracoscopic guidance through the second or third intercostal space-anterior axillary line. We also compare four different modalities of endoscopic denervation: A xenon chloride excimer laser (308 nm, 35 mJ/pulse, 20 pulses/sec, 2.2 mm catheter tip), CO2 laser (14 W, CW, 2 mm spot size), Nd:YAG laser (88 W, CW, 3 mm spot size), and radiofrequency-generated thermocoagulation (3 W, CW, 2.1 mm catheter tip) by performing bilateral thoracic sympathectomy on 12 mongrel dogs (three dogs each). Criteria analyzed included duration of exposure, power density, total energy output, laser penetration and spread, gross morphology, and scanning electron microscopy (SEM) of the destroyed neural tissue. Total ablation of the inferior segment of the stellate ganglion and the T1-T2 nerve roots by excimer laser required 83 +/1 1 Joules over an exposure period of 118 seconds. Ablation by CO2 and Nd:YAG laser required 153 +/- 13 Joules and 554 +/- 47 Joules delivered over 11 and 6 seconds respectively. In contrast, ablation of the same volume of nerve tissue by RF required 810 +/- 50 Joules over 270 seconds. SEM evaluation revealed that excimer and CO2 laser lesions were narrower in configuration compared to RF and Nd:YAG lesions which showed more lateral spread. The actual depth of penetration per 1 second exposure was similar for Excimer and CO2 (1.5 mm) and RF (1.3 mm), but deeper for Nd:YAG (3 mm).(ABSTRACT TRUNCATED AT 250 WORDS)