Spontaneous rupture of the thoracic aorta.

BACKGROUND: Spontaneous rupture of the thoracic aorta without trauma, aneurysm, or dissection is an extremely rare but catastrophic disorder. Two cases of spontaneous aortic rupture are presented, both treated surgically with satisfactory results. METHODS: A review of the English literature found 16 patients with the diagnosis of spontaneous rupture of the thoracic aorta from 1961 through 1998. Eighteen reported cases, including the 2 cases presented herein, are reviewed. RESULTS: The representative clinical picture is one of a middle-aged hypertensive patient with acute chest pain and collapse, with imaging modalities demonstrating hemopericardium, hemomediastinum, or hemothorax. According to the reported experiences, aortography was accurate for identifying the rupture site although the findings were sometimes subtle. Misdiagnosis or nonsurgical management resulted in the patient's death. All 8 patients who did not undergo aortic repair died within 3 weeks after the onset, whereas 9 of 10 patients who underwent surgical aortic repair survived. CONCLUSIONS: For patients with a definitive or possible diagnosis of spontaneous rupture of the thoracic aorta, prompt operation is imperative through an optimal surgical approach to identify and repair the rupture site with appropriate circulatory support.

Type A aortic dissection involving a right-sided aortic arch.

We report a rare case of a 39-year-old man with type A aortic dissection involving a right-sided aortic arch with the symptom of vascular ring. Computed tomography scanning and angiography were performed to define the extent of the dissection and the anatomy of the branching vessels. The ascending aorta was replaced through a median sternotomy and right thoracotomy using a hypothermic cardiopulmonary bypass associated with selective cerebral perfusion and partial circulatory arrest, and his symptom of vascular ring disappeared postoperatively.

[Left ventricular rupture following mitral valve replacement with preservation of posterior leaflet].

Left ventricular rupture following mitral valve replacement (MVR) with preservation of the posterior leaflet is presented. A 63-year-old man underwent combined AVR, MVR with preservation of the posterior leaflet and TAP under cardiopulmonary bypass with moderate hypothermiat to 28 degrees C and tepid blood cardioplegia. Although a 31-mm valve would fit to the mitral position, a 27 TEKNA was chosen for MVR. Beyond the cardiopulmonary bypass, a left ventricular rupture was found. Cardiopulmonary bypass was re-stated and the aortic clamp was replaced. After removal of the mitral valve prosthesis, an internal tear was detected below the anterolateral commissural area (Type I). The tear was repaired with two 3-0 monofilament buttressed sutures incorporated with felt strips and covered with a bovine pericardial patch by several interrupted pledgeted mattress sutures. Gelatin-resorcin-formaldehyde/Glutaraldehyde glue (GRF) was used to reinforce the ruptured myocardium and to fix a bovine pericardial patch to the affected ventricular wall. Then the prosthesis was re-seated. Although the aortic clamp time was 319 mins., the patient was weaned from the cardiopulmonary bypass easily with the prophylactic use of IABP. The patient was discharged and returned to his previous job.

[Surgical treatment of tricuspid regurgitation].

The purpose of this study is to compare early and late results of tricuspid valve replacement (TVR), tricuspid annuloplasty (TAP) and non operative management for patients with tricuspid regurgitation (TR). 5 patients underwent TVR and 70 patients received TAP (Kay-Boyd's annuloplasty in 16, Bex reducer method in 40, Carpentier's ring method in 14). 21 patients were managed non-operatively. The following results were obtained. TR should be repaired aggressively, if the regurgitation was more than second degree and tricuspid annulus was above three finger breadth. Judging from the pattern of residual TR after Kay-Boyd's annuloplasty and Bex reducer method, Bex reducer and Carpentier's ring should be placed over the three commissures except the conduction tract.

[The use of the bio-pump with an interposed soft reservoir in replacement of descending thoracic aortic aneurysms].

The centrifugal pump (bio-pump) as a temporary shunt during the operation of the descending thoracic aortic aneurysms was used as effective means of providing adequate circulation to the lower body. But in the acute excessive bleeding, estimates of the flow to the abdominal viscera as well as spinal cord are variable. We employed bio-pump with an interposed soft reservoir under low dose systemic heparinization in 2 cases of the descending thoracic aortic aneurysms. Both cases had been maintained adequate flow and perfusion pressure in the time of acute excessive hemorrhage, and there were no evidence of the organ failures due to microembolism. Furthermore, postoperative hemorrhage by using low dose heparin seemed to be unrisky. Compared with the previous method, bio-pump with an interposed soft reservoir provides adequate circulation to the lower body even if acute excessive bleeding occurred.

[Surgical treatment of chronic intestinal ischemia associated with combined valvular disease].

A 69-year-old male was admitted with congestive heart failure and postprandial abdominal pain with weight loss. Combined valvular disease (MR III+TR III) was demonstrated by cardiac catheterization. Selective visceral arteriography revealed 75% stenosis at the origin of SMA and common hepatic artery arose beyond the stenosis. SMA-abdominal aortic bypass grafting using auto-saphenous vein graft was performed initially. Postprandial abdominal pain disappeared after bypass grafting, and then MVR with Björk-Shiley mechanical valve and TAP with Carpentier- Edwards ring was performed.

[Surgical treatment of thrombosed aortic dissection].

We have performed the graft replacement of descending thoracic aorta for 6 patients with aortic dissection having non-opacified false channel on their initial CT and aortography from April 1990 to January 1993. We report the findings obtained from preoperative CT and aortographic findings and from operation with these patients. We also report the microscopic study of aortic wall resected at operation. In all the six patients were found by CT and angiography performed at the admission non-opacified false channel. In one patient, a re-dissection occurred at the mid-descending aorta four weeks later and extended into the abdominal aorta. Intimal tears were found during operation both at distal to the left subclavian artery and at mid-descending aorta in this patient, and microscopically the outer media of aortic wall had been ruptured and the advential scarring were more conspicuous than usual. In the other 5 patients, the local opacification was gradually increased in size during the follow up period. The site of local opacification was at the distal to the left subclavian artery in 3 and at the mid-descending aorta in 2. The operation for these patients revealed the existence of intimal tear at the involved aorta but the false channel had been closed. Microscopically, the involved aorta formed pseudoaneurysm and false channel had been closed with the organized thrombus. From these findings we conclude that surgical treatment should be considered for the aortic dissection when re-dissection occurred or local opacification was increased in size during follow up period, even if initial CT and aortography showed non-opacified false channel.

[A case of hemothorax occurred two months after graft replacement of descending thoracic aorta with Hemashield arterial prosthesis].

A 70-year-old man performed graft replacement of descending thoracic aorta for chronic aortic dissection (DeBakey IIIb) with Hemashield arterial prosthesis. He also had coronary artery disease (LAD seg. 7.99% stenosis) and he had received PTCA prior to operation. He was administered anticoagulants such as Aspirin and Warfarin postoperatively. Two months after operation, he complained dyspnea and came back to our hospital. Chest X-ray showed left hemothorax. CT scan and aortogram could not revealed bleeding points such as pseudoanerysm at anastomosis site nor new dissection. He recovered after discontinued anticoagulants and drainage. If you need to use the anticoagulants after graft replacement with Hemashield, you should administer the anticoagulants about 14 days after operation. This is the first clinical report that hemothorax occurred two months after graft replacement with Hemashield.

[Graft replacement for re-opacified thrombosed dissection].

A 55-year-old female was admitted with severe back pain. Enhanced CT demonstrated the descending aorta compressed by non-opacified false lumen. Ulcer like projection was found beyond the left subclavian artery by aortography. These findings suggested a type III aortic dissection with thrombosed false channel. 4 and 8 weeks later, although medical therapy was continued, she re-complained sever back pain. Repeat aortography revealed opacified false lumen arose beyond ULP and extended distally to the level of the celiac artery. Graft replacement was successfully performed using bio-pump as a temporary shunt.

[Clinical use of the multi-purpose circuit with a soft reservoir built in inflow side in replacement of the descending thoracic aorta].

The temporary bypass circuit under centrifugal pumping is generally applied for the assisted circulation of the operation for the aneurysm of descending aorta. The estimation of the bypass flow to the abdominal viscera, however, sometimes showed inadequate when excessive bleeding happened during operation. In order to keep constant flow to the lower body, we developed a new circuit, that has soft reservoir built in inflow side of the bypass line. In 8 subjects using this circuit, we studied the usefulness of the circuit and the choice of bypass route based on changes in the hemodynamics during bypass and operative complications in relation to bypass technique. During bypass, perfusion pressure to the lower body was 70-110 mmHg and flow was maintained at more than 21/min even if massive hemorrhage occurred. Comparing arterial bypass with LV bypass, the diastolic pressure in the upper limb was significantly depressed in arterial bypass with reading of 40-50 mmHg. Furthermore, in one case of arterial bypass involving the ascending aorta, false aneurysm is found in the site of cannulation. The rectal temperature dropped with the lapse of time from 35.5 +/- 0.8 degrees C to 33.5 +/- 0.4 degrees c in 120 min. These results indicate that multi-purpose circuit is capable of promptly supplying the circulating volume and is excellent means of providing adequate circulation to the lower body even if massive hemorrhage occurred. And LV bypass should be selected first, because arterial bypass has the hazard of depressing the diastolic pressure in the upper limb and involving complications associated with the insertion of cannula.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of visceral ischemia associated with acute type IIIb aortic dissection].

The case was a 61-year-old man who was transported to our hospital with complaining of severe chest and back pain of sudden onset and diagnosed as acute type IIIb aortic dissection. Inspite of intensive medical treatments, severe abdominal pain with abdominal distension and progressive metabolic acidosis appeared at around 11 hours after admission. Aortogram revealed obstruction of both superior and inferior mesenteric arteries suggesting visceral ischemia associated with acute type IIIb aortic dissection. Emergent operation consisting of bypass grafting for the superior and the inferior mesenteric arteries with saphenous vein, partial resection of small intestine, left hemicolectomy and construction of artificial anus was immediately carried out. The patient had no particular trouble after the operation and returned to the previous job.

Biochemical and hemodynamic changes in the hypertrophied dog heart subjected to chronic protein-calorie malnutrition.

Biochemical and hemodynamic changes were assessed in 13 dogs subjected to sub-coronary valvular aortic stenosis and chronic protein-calorie malnutrition (PCM). Red blood cell, hemoglobin, serum albumin, free fatty acids, blood glucose, cholinesterase and blood amino acid levels were measured. The dynamic geometry of the left ventricle (LV) was assessed with chronically implanted sonomicrometric piezoelectric crystals. Cardiac function was evaluated by mean velocity of circumferential fiber shortening (mean VcF) and the relationship between LV end-systolic pressure (LVESP) or LV wall stress (LVWst) and LV end-systolic diameter (LVESD). The following results were obtained: A decrease in body weight and increases in free fatty acids and 3-Methylhistidine were observed following long-term PCM. Mean VcF was not depressed in dogs subjected to PCM. The relationship between LVESP or LVWst and LVESD shifted downward and to the right after PCM, indicating reduced myocardial contractility. These findings suggest that the left ventricle in hypertrophied dog hearts subjected to PCM retains normal pump function, despite a low state in the myocardium.

Transfusion-associated graft-versus-host disease in immunocompetent patient: early diagnosis and therapy.

We report a case of transfusion-associated graft-versus-host disease in a previously healthy, 68-year-old Japanese man following an emergency surgery for an acute aortic dissection. We confirmed the chimerism of lymphocytes and the effect of drug therapy using DNA polymorphism analysis. This method is a sensitive, convenient, and rapid method that it is also useful for the evaluation of therapy. And the combination therapy with methylprednisolone, cyclosporine, and 15-deoxyspergualin may be effective in treating transfusion-associated GVHD.

Clinical evaluation of a leucocyte-depleting blood cardioplegia filter (BC1B) for elective open-heart surgery.

Activation of leucocytes during extracorporeal circulation has attracted attention in recent years as a cause of reperfusion injury in open-heart surgery patients. In the present study, 40 adult patients undergoing elective open-heart surgery were randomized into two groups: 20 using the Pall BC1B leucocyte-depleting filter for blood cardioplegia (group 1) and the other 20 without the filter (group 2). In order to determine if the filter was effective in protecting the myocardium, CPK-MB and troponin-T (TnT) were measured. In addition, efforts were also made to determine appropriate sites at which the BC1B blood cardioplegia filter should be positioned. There were no significant differences between the two groups in terms of conditions of perfusion. No adverse effects were seen in either group. The total leucocyte reduction rate through the filter was 98.1% with the passage of 2 liters of blood through the filter. A pressure drop of 4.4 +/- 3.2 mmHg was observed through the filter during use. Statistically significant differences were noted between the two groups in CPK-MB (p = 0.031) and TnT (p = 0.004). Findings obtained in previous studies demonstrate that the various advantages of leucocyte reduction, shown in experimental studies, can be translated into clinical advantages. In conclusion, based on the results in this clinical study showing significant difference in CPK-MB and TnT which are known effective indicators for myocardial injury, between leucoreduced and non-leucoreduced group, the Pall BC1B leucocyte-depleting filter for blood cardioplegia has been shown to be effective in alleviating reperfusion injury in open-heart surgery patients.

[Advantages of combined antegrade/retrograde GIK cardioplegia for coronary artery bypass surgery].

We evaluated the advantages of combined antegrade and retrograde GIK cardioplegia in 65 patients undergoing CABG. Thirty seven patients were administered antegrade cardioplegia (Group A), whereas 28 patients were administered combined antegrade and retrograde cardioplegia (Group C). Enzyme release and hemodynamic data were obtained before the onset of CPB and at 1, 3, 6, 9, 12 and 24 hours after operation. Both groups were similar in age and incidence of diabetes, previous MI, PTCA, severity of coronary artery disease and emergent operation. In group A, antegrade cardioplegia produced poor anterior septal cooling in 17 patients (45%). To ensure adequate myocardial protection in these cases 9, patients were anastomosed saphenous vein graft first to LAD instead of IMA and perfused cardioplegic solution through the grafts. In group C, although adequate anterior septal cooling also could not be obtained with antegrade cardioplegia in 16 patients (57%), after retrograde cardioplegia, anterior septal temperature fell below 10 degrees C. The use of IMA graft was more practiced in group C. (79% in group C versus 32% in group A, p < 0.05) Enzyme release (CPK-MB, %CPK-MB, LDH) and hemodynamic data (CI, LVSWI, RVSWI, RVEF, RVEDVI) were similar in both group. Furthermore, no significant difference were noted in the incidence of post-operative LOS, PMI and ventricular arrhythmia. We concluded that the use of combined antegrade and retrograde cardioplegia is more effective than antegrade cardioplegia, because of adequate anterior septal cooling, and it will allow patients with severe and extent coronary artery disease to undergo safe IMA grafting.