Successful Transcatheter Aortic Valve Replacement Approached Via a Simultaneously Implanted Y-graft Vascular Prosthesis

Transcatheter aortic valve replacement (TAVR) is mainly performed using the transfemoral (TF) approach. If the TF approach is difficult, the transapical (TA) or transaortic (TAo) approach is used; however, the complication rate is higher in such cases. In this case, abdominal aortic aneurysm (AAA) replacement and TAVR via artificial vessels were performed simultaneously because of anatomical difficulties in stent graft implantation and TF-TAVR for severe aortic stenosis (AS) associated with AAA. Performing TAVR simultaneously with AAA replacement avoids TA- or TAo-TAVR and allows for postoperative management in the absence of AS. Additionally, there is no need to create a new access for TAVR using artificial vessels. Since the long-term results of AAA are better with open surgery than with endovascular aneurysm repair and the age of indication for TAVR is expected to decrease due to valve-in-valve and other factors, simultaneous surgical AAA replacement and TAVR using a Y-graft vascular prosthesis is an effective treatment option when TF-TAVR is difficult to perform.

Device-Related Thrombotic Microangiopathy in an Elderly Patient With a History of Aortic Surgery

Thrombotic microangiopathy (TMA) is caused by several diseases, including infections, congenital and autoimmune diseases, and malignancies, usually requiring admission to intensive care. The primary pathophysiology of TMA is microvascular thrombosis, and its diagnosis is based on the presence of hemolysis, thrombocytopenia, schistocytes in a blood smear, and organ damage. Among secondary TMAs, device-related TMA could be difficult to diagnose if device implementation was performed years ago. We report the case of an 87-year-old woman with a chief complaint of dyspnea diagnosed with device-related TMA. In device-related TMA, thrombogenesis/thrombocytopenia is triggered by hemolysis/fragmented red blood cells. However, in other TMAs, thrombogenesis or thrombocytopenia is preceded by hemolysis and the presence of fragmented red blood cells. Thus, rapid plasma exchange is necessary to address TMA pathogenesis. TMA can be managed in a community hospital if the facility has access to plasma exchange. It is possible to treat complex TMAs even in community hospitals by carefully considering their pathophysiology. Additionally, improving the quality of general practice in community hospitals will allow for more effective diagnosis and treatment of TMAs.

Paediatric Takayasu's arteritis complicated by thrombotic occlusion of the distal thoracic aorta

We present the case of a 1-year-old girl with mid-aortic syndrome due to untreated Takayasu’s arteritis who developed cardiogenic shock. Enhanced computed tomography revealed long-segment occlusion of the distal thoracic aorta. We successfully performed graft interpose (10 mm in diameter) under cardiopulmonary bypass through both median sternotomy and left posterolateral thoracotomy. The thrombus was relatively small and the distal thoracic aorta was narrow over a long segment due to severely thickened intima. Follow-up computed tomography showed widely patent graft without a stenotic region in the abdominal aorta or its branches. The patient discharged ambulatory without major complications.

Hypothermic effects on gas exchange performance of membrane oxygenator and blood coagulation during cardiopulmonary bypass in pigs

INTRODUCTION

Whether hypothermic cardiopulmonary bypass could attenuate both blood coagulation and platelet activation compared to normothermic cardiopulmonary bypass remains elusive.

METHODS

Biocompatibility of a polymer-coated cardiopulmonary bypass circuit was comparatively assessed by plasma proteomics between juvenile pigs undergoing hypothermic (23°C) cardiopulmonary bypass and those undergoing normothermic (37°C) cardiopulmonary bypass (n = 6, respectively). Plasma samples were taken three times: 5 minutes after initiation of cardiopulmonary bypass (T5, before cooling), just before declamping and rewarming (Tc), and just before termination of cardiopulmonary bypass (Trw, 120 minutes). Proteomic analysis was quantitively performed by isobaric tags for relative and absolute quantification labeling. Thrombin-antithrombin complexes (TAT III) were measured by enzyme immunoassay, and vitamin K-dependent protein C (PROC), β-thromboglobulin (TG), and P-selectin were measured by enzyme-linked immunosorbent assay. Blood gas analyses evaluated oxygenator performance.

RESULTS

Hypothermic cardiopulmonary bypass had a significantly higher PaO₂ at Tc and lower PaCO₂ at Trw than normothermic cardiopulmonary bypass. Two hundred twenty-four proteins were identified with statistical criteria of both protein confidence (>95%) and false discovery rate (<5%). Six of these proteins significantly decreased at Tc than at T5 in hypothermic cardiopulmonary bypass (p = 0.02-0.04), with three related to platelet degranulation. Protein C decreased at Trw compared with T5 in normothermic cardiopulmonary bypass (p = 0.04). Thrombin-antithrombin complex had a slightly larger increase with normothermic cardiopulmonary bypass at Trw than with hypothermic cardiopulmonary bypass. β-thromboglobulin and P-selectin levels were significantly lower at Trw with hypothermic cardiopulmonary bypass than with normothermic cardiopulmonary bypass (p = 0.04).

CONCLUSION

Hypothermic cardiopulmonary bypass attenuated platelet degranulation/blood coagulation and maintained better oxygenator performance compared to normothermic cardiopulmonary bypass in juvenile pigs.

Recovery from very long aortic cross-clamping in redo complex aortic surgery

A 68-year-old man had undergone ascending aortic replacement for acute type A aortic dissection. Three months later, he had a new aortic dissection with an ulcer-like projection located in the aortic arch with suspected graft infection. An emergent redo total aortic arch and root replacement was performed because of the coexistence of a fragile aortic root wall. The extensive redo procedure necessitated a very long aortic cross-clamping time (516 min). After 25 min of assisted circulation, he was easily weaned from the cardiopulmonary bypass. Finally, an omental flap was harvested to cover the graft. Postoperative ECG and CK-MB examinations showed no significant myocardial injury. He had no symptoms of heart failure and was discharged after a month of antibiotic therapy. One-year follow-up UCG study revealed no abnormal findings except for signs of pericardial adhesion.

Polymer-coated cardiopulmonary bypass circuit attenuates upregulation of both proteases/protease inhibitors and platelet degranulation in pigs

Introduction:

Interaction of blood with a cardiopulmonary bypass (CPB) circuit activates the coagulation-fibrinolysis, complement and kinin-kallikrein systems that are mainly supported by proteases and their inhibitors.

Methods:

Biocompatibility of a new polymer-coated (SEC-coated) CPB circuit was globally evaluated and compared with that of a non-coated CPB circuit by quantitative proteomics, using isobaric tags for relative and absolute quantification labeling tandem mass spectrometry. Plasma samples were taken three times (5 min after initiation of CPB, just before declamping and just before termination of CPB) in 12 pigs undergoing 120 min of CPB with the SEC-coated CPB circuit or a non-coated CPB circuit (n = 6, respectively).

Results:

Identified were 224 proteins having high protein confidence (>99%) and false discovery rate (FDR) <5%. Among these proteins, there were 25 significantly upregulated proteins in the non-coated CPB group compared to those in the SEC-coated CPB group. Dominant protein functions were platelet degranulation, serine-type (cysteine-type) endopeptidase inhibitor activity and serine-type endopeptidase activity in the 25 proteins. Bioinformatics analysis similarly revealed upregulation of proteins belonging to platelet degranulation and negative regulation of endopeptidase activity in the non-coated CPB group; these upregulations were effectively attenuated in the SEC-coated CPB group.

Conclusion:

The new polymer (SEC)-coated CPB circuit effectively attenuated upregulation of proteins compared to the non-coated CPB circuit. These proteins were associated with both proteases/protease inhibitors and platelet degranulation.

A case of staged Norwood procedure for a unique form of truncus arteriosus, interrupted aortic arch with hypoplastic tricuspid valve and right ventricle and anomalous left coronary artery orifice: first reported case

We present the first reported case of truncus arteriosus, interrupted aortic arch with hypoplastic tricuspid valve and right ventricle and anomalous left coronary artery orifice in a neonate in whom successful palliation was performed using two-staged procedure. The first-stage palliation was the bilateral pulmonary artery band at age 2 days. The second-stage palliation was a Norwood procedure concomitant with ASD creation and patch augmentation of the pulmonary artery confluence at 22 days. The patient is doing well, with unobstructed aortic arch and mild truncal valve regurgitation.

[Resection of Recurrent Leiomyosarcoma of the Inferior Vena Cava with Extention into the Right Atrium and Z stent implantation；Report of a Case]

79-year-old woman, who had undergone resection of a leiomyosarcoma of the inferior vena cava(IVC)[at 68 years old], was admitted to our hospital due to local recurrence of the leiomyosarcoma with extention into the right atrium (RA). She had progressive dyspnea and bilateral edema of the lower extremities. A computed tomography (CT) scan revealed a tumor that obstructed the IVC. A transthoracic echocardiography showed a large mobile right atrial mass. To prevent sudden death, a reoperation was performed. The tumor in the IVC and the RA was resected under deep hypothermic circulatory arrest. A postoperative CT scan showed stenosis of the IVC by residual tumor, and a Z-stent was therefore implanted in the IVC. Postoperative recovery was uneventful and the patient no longer showed any symptoms.

Senning operation for very low birth weight infant with transposition of the great arteries: one of the smallest cases in the world

We report a case of a Senning operation for very low birth weight infant weighing 1,168 g with transposition of the great arteries. The patient underwent a Senning operation on 62 days, 1,700 g after the first palliation. In this case, the orifice of the left anterior descending artery was located in sinus 1 (left posterior facing sinus), but we could not find orifices of both right coronary artery and left circumflex artery before the Senning operation. The surgical procedure of the Senning operation is typical one, but we used flesh autopericardial patch to cover the roof of the new pulmonary vein chamber to get an enough size. The patient recovered with no cardiac events after the repair.

Cardiac tamponade due to rupture of coronary artery fistula to the coronary sinus with giant aneurysm of coronary artery: usefulness of transthoracic echocardiography

A 68-year-old woman was admitted to our hospital because of back pain and syncope. Transthoracic echocardiography revealed pericardial effusion, a collapsed right ventricle, a giant aneurysm connected to the coronary sinus, a dilated left main trunk coronary artery, and a dilated left circumflex artery (LCx). Furthermore, there was a coronary artery fistula arising from the LCx that drained into the coronary sinus. We diagnosed cardiac tamponade due to rupture of the coronary artery fistula or giant aneurysm, and successful emergency surgery was performed. Rupture of coronary artery aneurysm or coronary artery fistula is very rare. Transthoracic two-dimensional echocardiography was very useful in our case for the diagnosis of cardiac tamponade, giant coronary aneurysm, and coronary artery fistula.

[Intermittent opening of a mechanical mitral valve prosthesis due to pannus formation; report of a case]

A 76-year-old woman with a history of severe mitral valve stenosis had undergone mitral valve replacement with a 27 mm St. Jude Medical (SJM) valve in 1991. Follow-up transthoracic echocardiography revealed an increase in the pressure gradient across the mitral prosthesis 16 years after the surgery. Prosthetic valve dysfunction was suspected, but transesophageal echocardiography and cineradiography failed to show mechanical valve dysfunction. Two years later, she presented with dyspnea on exertion and leg edema. Cineradiography revealed intermittent restriction of the opening of the mechanical valve leaflet approximately every 10 beats. Thus, we diagnosed intermittent prosthetic valve dysfunction and performed a reoperation. On inspection of the prosthesis, we observed semicircular pannus formation around the posterior leaflet in the ventricular side. It was considered that the pannus tissue had interfered with 1 leaflet opening of the mitral valve prosthesis, resulting in intermittent valve dysfunction. We replaced the prosthesis with a new 25 mm SJM valve. The patient was discharged after confirmation of normal prosthetic function.

[Graft harvesting in coronary artery bypass grafting]

The technique of graft harvesting during coronary artery bypass grafting (CABG) consists of 2 main components: the vessel exposure at an adequate layer and the division of branches. Recently, the ultrasonic scalpel has been used for skeletonization of arterial grafts. A hook-type tip is used for the internal thoracic artery and the radial artery graft, while a shear type tip is used for the right gastroepiploic artery graft. The ultrasonic scalpel is useful both for graft vessel exposure and for the division of branches. The cavitation phenomenon is useful for the vessel exposure, while ultrasonic protein coagulation is useful for the division of branches. In endoscopic saphenous vein graft harvesting, electrocautery scissors are used for the division of branches. Avoiding thermal damage to the graft vessel is important in the use of either device. In any graft harvesting, direct contact with the main trunk should be avoided as much as possible to prevent damage. A thorough knowledge of the anatomy of the graft vessel and the surrounding organs is necessary for graft harvesting and to avoid complications. Furthermore, an understanding of characteristics of the harvesting devices is also important.

[Long-term evaluation of aortic root replacement using Svensson technique with multislice computed tomography]

The Svensson technique of aortic root composite valve graft replacement, which involves reimplantation of the left coronary ostium with a long interposed graft wrapping behind the composite graft, is technically simple and advantageous. However, surgeons must be concerned about complications regarding the long interposed graft in the long-term follow-up. In 32 cases with the Svensson technique, we evaluated their replaced aortic roots by multislice computed tomography (MDCT) at 4.5 +/- 3.6 years (maximum, 14.9 years) postoperatively. The mean age was 54.5 +/- 14.1 years and 22 patients were male. No patients have experienced any complications regarding the technique at the follow-up of 6.9 +/- 4.9 years (maximum, 16.4 years). No structural complications were detected by MDCT of all patients. In conclusions, the Svensson technique was demonstrated to be favorable with no technical problems in the long-term evaluations with MDCT. The Svensson technique can be considered as a justifiable technique in any aortic root replacements including complicated or redo aortic roots.

[New proximal anastomotic system in coronary artery bypass grafting]

The Heartstring proximal anastomotic system is a device designed to facilitate the creation of a clampless hand-sewn proximal anastomosis. Thirty-four patients who underwent coronary artery revascularization had 40 proximal anastomoses using the Heartstring device. There were 26 men and 8 women, with the mean age of 70 +/- 8.9 years. Thirty-one patients underwent coronary artery bypass grafting through off-pump procedures and 3 patients on-pump beating procedures. In all patients, saphenous vein grafts were anastomosed to the aorta using the Heartstring device, the median number of distal anastomoses being 2.4 +/- 0.7. Either emergent or urgent surgery was required in 14 patients (41%). Diseased aorta was found in 11 patients (32%). One patient (2.9%) died postoperatively due to ischemic necrosis of the small intestine and the colon. There was no occurrence of postoperative stroke. Of 40 saphenous vein grafts anastomosed with the Heartstring system, 39 (97.5%) were patent. The occluded saphenous vein was not considered to be device related. Our clinical experience demonstrated that the Heartstring system allow us to create clampless and reproductive hand-sewn proximal anastomosis and to decrease the incidence of neurological complication.

[Aortic root replacement in Marfan syndrome with hemophilia A]

A 34-year-old man with Marfan syndrome was admitted to our hospital for surgical treatment of aortic regurgitation due to annuloaortic ectasia. He had no history of bleeding complications. Preoperative investigation revealed a slight prolongation of an activated partial thromboplastin time, which went unnoticed. He underwent aortic root replacement with a composite valve graft. During the operation, he had excessive bleeding due to coagulopathy after the termination of cardiopulmonary bypass, and needed a large amount of blood transfusion to obtain hemostasis. Before his discharge from our hospital, he was diagnosed as mild hemophilia A because of the decline in his factor VII level. To our knowledge, there has been no published case of cardiac operations in Marfan syndrome with hemophilia A.

[Successful off-pump coronary artery bypass for a patient with aplastic anemia]

We report a 61-year-old man with aplastic anemia who underwent successful off-pump coronary artery bypass (OPCAB) after being admitted for angina pectoris. Coronary angiography showed severe stenosis of the left main coronary artery. Preoperative WBC was 2,200/microl, neutrophil 704/microl, Hb 8.1g/dl, and PLT 16,000/microl. We conducted OPCAB on double vessels using left internal thoracic and radial artery grafts. Thirty units of platelets were transfused intraoperatively with little perioperaive hemorrhage. Because of high grade fever, we injected 150 microg granulocyte colony-stimulating factor (G-CSF) every 3 days postoperatively to prevent major infection. The combination of appropriate perioperative management and OPCAB yielded an effective result for a patient with severe hematological disorders causing pancytopenia.

[Bronchial artery embolization for treatment of mediastinal hemorrhage after pulmonary resection: report of a case]

We report a rare case of mediastinal hemorrhage after pulmonary resection. A 64-year-old woman with hypersensitivity pneumonitis was diagnosed as adenocarcinoma of the lung by bronchoscopical examination. Left lower lobectomy and mediastinal lymph node dissection were performed. Sudden chest pain and dry cough developed 14 days after the operation. Her diastolic pressure rose transiently but electrocardiogram remained normal. Chest X-ray showed widening of the mediastinum and enhanced chest computed tomography (CT) showed extravasation of the contrast media just under the bifurcation of the trachea. Multi projection volume reconstruction revealed mediastinal hemorrhage from the bronchial artery. The chest pain disappeared after a successful bronchial artery embolization and the patient discharged 21 days later. Hemorrhage after pulmonary resection is a common complication, but no previous report has described mediastinal hemorrhage occurring 2 weeks after the operation. In a similar case, bronchial artery embolization is a reliable and minimally invasive therapy for mediastinal hemorrhage.

FK778 controls acute rejection after rat liver allotransplantation showing positive interaction with FK506

This study including prevention and rescue experiments was performed to examine the efficacy of FK778 and its interactions with FK506. In the prevention experiment, Brown-Norway rats transplanted with a 7 Lewis livers received day-course of FK778 or a combination of FK778 and FK506 treatment. For the rescue experiment, the recipients were additionally treated with FK778 from days 7 to 13. Blood chemistry and histopathological findings were used to examine the host and the graft condition. Donor-specific IgM was measured using enzyme-linked immunosorbent assays. The serum trough level of FK778 was examined by high-performance liquid chromatography. FK778 suppressed acute rejection in a dose-dependent manner. The optimal FK778 dosage was 20 mg/kg body weight (BW) d. FK778 treatment from days 7 to 13 rescued liver grafts from ongoing rejection. The combination of FK506 (0.125 mg/kg BW/d) and FK778 (20 mg/kg BW/d) maintained better graft condition than FK778 (20 mg/kg BW/d) monotherapy. In conclusion, FK778 prevents acute rejection in and rescues transplant recipients from ongoing rejection after rat liver transplantation. The optimal monotherapy dosage of FK778 was 20 mg/kg BW/d. Combination therapy with FK506 was more beneficial than FK778 monotherapy.

Mitochondrial KATP channel opener prevents ischemia-reperfusion injury in rat liver

Ischemia-reperfusion injury is responsible for the morbidity associated with liver surgery under total vascular exclusion or after liver transplantation. Recently, it has been reported that mitochondrial K(ATP) channel openers have an effect on myocardial protection via a pharmacological preconditioning action. However, it remains unclear as to whether K(ATP) channel openers can reduce ischemia-reperfusion injury in the liver. The aim of this study was to determine the effects of the mitochondrial K(ATP) channel opener, nicorandil, on ischemia-reperfusion injury in the rat liver. Male Wistar rats were subjected to 73% ischemia for 45 minutes followed by 120 minutes of reperfusion. Nicorandil (3 mg/kg) was orally administered 60 minutes before hepatic ischemia. Nicorandil significantly decreased plasma levels of alanine aminotransferase and lactate dehydrogenase by about 50% and inhibited the remarkably increased TUNEL-positive hepatocytes after reperfusion. Some mediators associated with apoptosis were analyzed by Western blotting. Cytochrome-c and caspase-3 levels in the cytosol increased after reperfusion; nicorandil inhibited the release of cytochrome-c and activation of caspase-3. The expression of Bax and Bcl-2 was significantly increased after reperfusion, being slightly inhibited by the administration of nicorandil. These results suggest that the protective effects of nicorandil against hepatic ischemia-reperfusion injury correlate with the inhibition of mitochondrial cytochrome-c release and caspase-3 activation. These findings demonstrate that nicorandil may become a therapeutic drug for ischemia reperfusion-related liver injury.

Bilateral video-assisted thoracoscopic surgery in the supine position for primary spontaneous pneumothorax

On the basis of the bilateral nature of bullous lesions of the lung, the authors have performed single-stage bilateral video-assisted thoracoscopic surgery (VATS) in the supine position for primary spontaneous pneumothorax in five patients since October 1999. All five patients were males with a mean age of 23 years (range 19 to 29 years). The presenting pneumothorax was ipsilateral (right-sided) in four patients and simultaneous bilateral in the one remaining patient. Apart from the one case of simultaneous bilateral spontaneous pneumothorax (SBSP), all patients had a history of at least one pneumothorax episode requiring tube thoracotomy. Bilateral bullae were confirmed in all patients on preoperative chest computed tomography (CT). Bilateral bullectomy was performed by endo-stapler with no difficulties. Mean operating time was 111 minutes (range 85 to 140 minutes). All patients were returned to the surgical ward in good condition from the operating room immediately after extubation. No complications were observed, and duration of postoperative hospital stay was two to four days. All patients were alive without recurrence of pneumothorax after a mean follow-up period of 25 months (range, 9 to 43 months). Single-stage bilateral VATS in the supine position has shown itself to be an excellent approach for the treatment of bilateral bullous lesions, combining both efficacy and low morbidity.

The Variable Effects of Dopamine Among Human Isolated Arteries Commonly Used for Coronary Bypass Grafts

The direct actions of dopamine on human arterial coronary bypass grafts are not well known. We investigated its effects on isolated rings cut from radial arteries (RA), gastroepiploic arteries (GEA), and internal mammary arteries (IMA) harvested from patients undergoing coronary artery bypass surgery. Dopamine produced dose-dependent contractile responses in RA, an effect independent of the presence of a functional endothelium. The contractions were enhanced by the dopamine A(1) (DA(1))-receptor antagonist SCH23390, whereas they were blocked by an alpha(1)-adrenergic antagonist, prazosin. Results qualitatively similar to these were obtained in both GEA and IMA, although the contractile responses were far smaller. In RA, DA enhanced the norepinephrine (NE)-induced contraction, and this action of dopamine was enhanced by SCH23390. In GEA, small concentrations (<10(-7) mol/L) of DA attenuated the NE-induced contraction but larger concentrations did not. In IMA, DA induced a vasorelaxation on the NE-contraction only at higher concentrations (10(-6)-10(-5) mol/L). In both GEA and IMA, the dopamine-induced vasorelaxations on the NE contraction were completely inhibited by SCH23390. These results suggest that the affinities of DA for DA(1)- and alpha(1)-adrenergic receptors may explain its variable contractile and vasorelaxant effects among these arteries.

IMPLICATIONS

Differing affinities of dopamine for dopamine A(1)- and alpha(1)-adrenergic receptors may lead to it having variable contractile and vasorelaxant effects among the arteries supplying grafts for coronary bypass surgery.

Placement of the Dumon Stent Using a Flexible Bronchofiberscope via Tracheostomy

In this paper, we report on a new technique of Dumon stent placement using a flexible bronchofiberscope. This procedure was used to insert Dumon stents in two bronchial obstruction and two bronchofistula cases. The stenting technique described here can be used through either a tracheostoma or the oral cavity; it presents a very straightforward and safe procedure that does not require the use of a rigid bronchoscope.

[Redo coronary artery bypass operation under beating heart via the left thoracotomy reusing patent grafts]

We report three cases of successful redo coronary artery bypass grafting (CABG) under beating heart via left thoracotomy with recycling of patent grafts previously implanted. Case 1 and 2: Anginal attack relapsed due to occlusion of the proximal portions of saphenous vein grafts (SVG) that had been sequentially anastomosed to the left coronary artery branches. In each case, the distal portion of the SVG was patent and functioned as coronary-coronary bypass. The left internal thoracic artery graft (ITAG) anastomosed to the left anterior descending coronary artery (LAD) was patent. Each patient underwent off-pump CABG through a left posterolateral thoracotomy. CABG was performed with the radial artery to the circumflex coronary artery (case 1) or the circumflex coronary artery and previous SVG (case 2). The proximal ends of radial artery grafts were anastomosed to the descending aorta. Case 3: Simultaneous reoperative CABG and the operation for the pseudoaneurysm that developed after the abdominal aortic graft replacement were performed. Bypass grafting between ITAG and LAD was performed with SVG via a left anterolateral thoracotomy because of severe anastomotic stricture of ITAG-LAD. The postoperative courses was uneventful for all patients.

[In situ graft replacement for the thoracoabdominal aortic aneurysm with abscess around the aorta; report of a case]

A 58-year-old woman who complained of epigastralgia, back pain and pyrexia was admitted for further examination. A computed tomography (CT) scan revealed an abnormal mass between the descending aorta and esophagus. Exploratory thoracotomy was performed and brown purulent fluid was drained from the mass. Postoperatively, the white blood cell count normalized and the patient become afebrile. Eleven days postoperatively, circa 500 ml of blood discharged from a chest drain tube. A CT scan demonstrated enlargement of the thoracoabdominal aorta, necessitating an emergency operation. A pseudoaneurysm was found in the thoracoabdominal aorta, with inflammation in the aortic wall. On opening the aneurysmal sac, the intima of the aorta was found to have a partial defect. In situ graft replacement of the thoracoabdominal aorta and reconstruction of the intercostal artery were performed. Finally, a pedicled omental flap was used to cover the artificial graft. Two years postoperatively, the patient is doing well with no recurrence of infection.

Gallium-67 scintigraphy in the diagnosis and management of chronic sarcoid myopathy

The authors describe a patient with chronic sarcoid myopathy. Except for the presence of left posterior synechia, no other organ involvement was observed. Gallium-67 ((67)Ga) scintigraphy showed many intense nodular uptake areas in both the upper and lower extremities. Treatment with oral prednisolone 30 mg/day resulted in a marked improvement on (67)Ga scintigraphy. This case suggests that (67)Ga scintigraphy is useful for the differential diagnosis of systemic myopathies and also for monitoring the effect of glucocorticoid treatment.

[Aortic root replacement using cryopreserved allograft for an infected aorta patient associated with mediastinitis]

We herein report a case of aortic root replacement using cryopreserved allograft. A 52-year-old man received aortic valve replacement using a mechanical prosthesis for aortic stenosis. He was complicated by postoperative methicillin-resistant staphylococcus aureus mediastinitis involving the ascending aorta. Surgical therapy including debridement, omental transposition, patch closure using pericardium had not achieved satisfied result. Aortic root replacement using cryopreserved allograft was mandatory for refractory aortic infection. He had an uneventful postoperative course. The cryopreserved allograft was effective for a patient with refractory aortic root infection due to postoperative mediastinitis.

[Long-term results of aortic arch replacement using combination of deep hypothermic circulatory arrest and retrograde cerebral perfusion; comparison of result for atherosclerotic aneurysm and aortic dissection]

Between 1992 and 2001, 73 patients with aortic arch lesion underwent surgical treatment. The aneurysm was characterized by atherosclerosis in 54 patients (TAA) and by aortic dissection in 19 patients (DAA). All patients received graft replacement under combination of deep hypothermic circulatory arrest and retrograde cerebral perfusion. The hospital mortality rate for all patients was 15.6%. The follow-up period of 61 survival patients ranged from 2 to 90 months (mean 33.2 months). The actuarial survival rate was 93.2%, 83.5%, and 79.7% at 1, 3, and 5 years, respectively. No significant difference was noted between TAA and DAA in the actuarial survival rate. The freedom from vascular complication was 97.9%, 95.8%, and 95.8% at 1, 3, and 5 years, respectively. The rate was significant higher in the patients of DAA than in those of TAA (TAA: 100%, 100%, and 100%, DAA: 90.9%, 81.8%, and 81.8%). The freedom from cardiac complication was 96.4%, 89.7%, and 84.1% at 1, 3, and 5 years, respectively. There was no significant difference between TAA and DAA. The freedom from cerebrovascular complication was 100%, 97.6%, and 83.4% at 1, 3, and 5 years, respectively. No significant difference was noted between TAA and DAA. The late result of surgical treatment for the aortic arch using combination of deep hypothermic circulatory arrest and retrograde cerebral perfusion was satisfied. The long-term survival rate was higher in TAA patient than in DAA one. The possibility remained that fatal vascular complication affected the long-term survival rate.

Early and long-term results of coronary artery bypass grafting in dialysis patients

OBJECTIVE

We evaluated the surgical outcome of coronary artery bypass grafting in dialysis patients.

METHODS

We retrospectively analyzed 25 consecutive dialysis patients requiring isolated coronary artery bypass grafting. Their mean age was 61.6 years and average dialysis duration 80.4 months.

RESULTS

Eight patients (32%) had emergency or urgent surgery. The mean number of bypassed vessels was 3.3 +/- 1.2. Internal thoracic artery grafts were used in 19 patients and gastroepiploic artery grafts in 5. Two (8%) died during hospitalization and complications occurred in 11 (44%). No cerebral complications were observed. All survivors showed ameliorated symptoms and improved overall function. Of 14 late deaths, 5 were cardiac-related, with 2 involving obvious myocardial ischemic events. Actuarial survival, including hospital deaths, at 1 year was 70.9%, at 3 years was 43.5%, and at 5 years was 34.8%. Cardiac-death-free survival was 70.2% at 3 years and 70.2% at 5 years.

CONCLUSION

Coronary artery bypass grafting in dialysis patients is associated with a higher incidence of complications but has acceptable surgical mortality and effectively relieves angina symptoms.

Metastatic synovial sarcoma of the left ventricle

A metastatic synovial sarcoma of the left ventricle is described. A 26-year-old Japanese woman underwent resection of a synovial sarcoma of the right thigh 8 years prior to admission, which was followed by multiple surgical procedures for pulmonary metastasectomy. Echocardiography demonstrated obstruction of the outflow tract of the left ventricle caused by a metastatic tumor, which was surgically resected on the day of admission. The histologic characteristics of the cardiac tumor were identical to those of the pulmonary metastases. Additional cardiac metastasectomy was performed 9 months later. She complained of dyspnea on exertion 8 months after the second cardiac metastasectomy due to recurrence in the heart. Radiotherapy with LINAC (a total dose: 50 Gy) diminished the size of the tumor temporarily. The patient died 20 months after the initial cardiac metastasectomy.

Aortic valve replacement in a patient with factor XII deficiency: case report

Congenital factor XII deficiency is a rare condition. We report a case of aortic valve replacement (AVR) in a 63-year-old man with factor XII deficiency. On admission, the patient's activated partial thromboplastin time (aPTT) was prolonged (271 s), and activated clotting time was 500 s. His factor XII level was <3%. The Sonoclot signature showed an abnormal pattern. AVR with a prosthetic valve (St. Jude Medical) was performed safely after the normalization of aPTT and the Sonoclot signature by frozen plasma transfusion. The perioperative management in patients with factor XII deficiency is discussed.

Slow induction of milrinone after coronary artery bypass grafting

The aim of this study was to evaluate the hemodynamic effects of a slow induction of milrinone after open heart surgery. Twenty patients who underwent elective coronary artery bypass grafting were randomized into two groups, with 10 patients receiving a continuous infusion of milrinone (5 microg/kg/min) (group M), and 10 patients undergoing treatment without milrinone (group C). This is a preliminary study for evaluating the efficacy of a slow induction of milrinone, so patients in low cardiac output state were excluded. A continuous infusion without an initial loading dose was initiated in the intensive care unit. Hemodynamic parameters and the concentration of milrinone were measured 90 minutes and 3 hours after initiation of the milrinone infusion. A significant decrease in arterial pressure occurred at 3 hours in group M, and both the systemic vascular resistant indices decreased significantly (p<0.05) at 90 minutes. No significant changes occurred in group C. Cardiac index and heart rate increased significantly (p<0.05) in group M, but were unchanged in group C. No significant change in double product was observed in either group. Hypotension (systolic blood pressure less than 100 mmHg) or arrhythmia did not occur in group M. The concentration of milrinone at 90 minutes and 3 hours was 97+/-22 and 124+/-27 ng/ml, respectively. A slow induction of milrinone is safe and effective in patients following cardiac surgery.

Mitral valve replacement in a patient with a collapsed lung

A 67-year-old man, with a history of pulmonary tuberculosis since 18 years old, presented shortness of breath because of severe mitral regurgitation. Magnetic resonance imaging showed that the heart was displaced into the left thoracic cavity and rotated clockwise around its long axis. The forced expiratory volume per second was 1.06 l (46.7% of the predicted value) and the vital capacity was 2.48 l (72.1% of predicted value). Surgery was performed through a median sternotomy. An internal mammary artery harvest retractor was used to obtain operative exposure. Extensive pericardial suspension was used to push the over-inflated right lung across the midline. Extracorporeal circulation was established. The mitral valve was replaced with a mechanical prosthesis. The patient was weaned easily from extracorporeal circulation and was extubated on the day of surgery. If preoperative respiratory function is adequate, cardiac surgery can be performed safely in a patient with only one functional lung.

Use of A heparin-coated circuit for extracorporeal circulation with selective cerebral perfusion

The use of selective cerebral perfusion with a heparin-coated extracorporeal circuit has not been reported. We developed a unique extracorporeal circulation system that can be used for selective cerebral perfusion based on an existing heparin-coated circuit with a centrifugal pump for general open-heart surgery and a heparin-coated oxygenator without venous drainage by gravity. Between July 1994 and December 1999, this system was used for 12 patients undergoing surgery for true aortic arch aneurysm. The dose of heparin used was reduced to maintain minimum activated clotting time above 300 sec during extracorporeal circulation. One patient suffered a stroke, and one patient had transient postoperative neurologic deficit. One patient died suddenly of ventricular arrhythmia on the 11th postoperative day. The circuit remained thrombus-free. Selective cerebral perfusion with a heparin-coated bypass circuit was safe and very easy to perform after a simple modification of a standard circuit for open-heart surgery.

Early surgery for active infective endocarditis

OBJECTIVE

The timing of surgery for active infective endocarditis remains controversial. In this report, we have reviewed 26 patients who underwent surgery for active infective native-valve endocarditis between April 1992 and December 1998.

PATIENTS AND METHOD

There were 19 male and 7 female patients (mean age 45 years). The aortic valve was involved in 8 patients, the mitral valve in 6 patients, tricuspid valve in 2 patients, both aortic and mitral valves in 7 patients, both aortic and tricuspid valve in 2 patients, and both mitral and tricuspid valve in one patient. The most common microorganisms were streptococcal species. Preoperative high New York Heart Association functional class (III and IV) was presented in 20 patients (77%). Progressive heart failure and the echocardiographic findings of vegetation (larger than 1 cm) were the main operative indications. Emergency or urgent surgery was required in 18 patients (70%). All patients underwent valve replacement, involving 25 mechanical prosthesis and 8 bioprosthesis.

RESULTS

The operative mortality was 7.8% (n = 2). In the two patients who died, the infection had extended to the deep cardiac tissue and to the cerebral artery. The mean follow-up of the 24 survivors was 33 months (range from 6 to 82 months). There was no late death and no recurrence of infective endocarditis.

CONCLUSION

In case of active infective endocarditis, early surgical intervention is recommended in patients with rapidly progressive cardiac deterioration or vegetation seen on echocardiography.

Neointimal formation at the sites of anastomosis of the internal thoracic artery grafts after coronary artery bypass grafting in human subjects: an immunohistochemical analysis

OBJECTIVES

The aim of this study was to evaluate the cellular composition and cell proliferative activity of neointimal tissue in human internal thoracic artery grafts and to characterize the differentiation state of neointimal smooth muscle cells at early stages after coronary artery bypass grafting.

METHODS

The anastomotic sites and body segments of 7 patent grafts were obtained at autopsy from 7 patients who died within 92 days after operation. Serial sections were examined by immunohistochemical techniques to identify macrophages, endothelial cells, smooth muscle cell phenotype, and proliferating cells. For the identification of the cell types that show cell proliferative activity, immunodouble staining was also performed.

RESULTS

In all body segments the luminal surface was completely covered by endothelial cells, and no areas showed thrombus formation or neointimal proliferation after grafting. In contrast, in the anastomotic segments endothelial denudation and focal disruption of the internal elastic lamina with adherence of fibrin-platelet thrombus and infiltration of macrophages were observed in the earliest stage after grafting. At these sites of injury, early neointimal tissue response had occurred, and cell proliferative activity was detected in macrophages and dedifferentiated smooth muscle cells. During the evolution of neointimal thickening, redifferentiation of neointimal smooth muscle cells occurred associated with the decline in proliferative activity.

CONCLUSIONS

These observations strongly support the concept that excessive neointimal proliferation, which may occur at the site of anastomosis because of extensive damage to the arterial wall, could be one of the possible causes of failure of the internal thoracic artery graft in human beings.

Duplex scanning to assess radial artery suitability for coronary artery bypass grafting

OBJECTIVE

Radial artery suitability in coronary artery bypass grafting was assessed using duplex ultrasonography.

SUBJECTS AND METHODS

The vascular condition along the entire radial artery was scanned in 55 patients, measuring the internal diameter and mean flow velocity at the wrist (distally), after ulnar artery branching (proximally), and midway between these 2 points (medially). Distally along the radial and ulnar arteries, the mean flow velocity was determined before and after radial artery occlusion.

RESULTS

Atherosclerotic changes were detected in 4 patients. The internal diameter was 3.1 +/- 0.4 mm proximally, 2.7 +/- 0.3 mm medially, 2.4 +/- 0.4 mm distally. The distal flow velocity was 0, and a reverse flow (peak velocity: 11.3 +/- 6.0 cm/s) was observed after the occlusion test in patients with an intact palmar arch, their mean flow velocity, 21.1 +/- 8.9 cm/s, and flow distally along the ulnar artery 58.0 +/- 23.4 ml/min, were higher after the occlusion test than before it 14.7 +/- 6.7 cm/s mean flow and 38.1 +/- 15.9 ml/min distally. This was not observed in patients with an interrupted palmar arch. In 15 patients, radial arteries could not be used because of their small internal diameter, lack of a radial artery, poor vascular condition, or an interrupted palmar arch evaluated using duplex scanning.

CONCLUSION

Reliable noninvasive assessment of radial artery anatomy and palmar arch continuity is thus possible using duplex ultrasonography.

[Successful aortic root replacement for prosthetic valve endocarditis using the freestyle stentless bioprosthesis: report of two cases]

We report two cases of prosthetic valve endocarditis which were successfully treated with aortic root replacement using the freestyle stentless bioprosthesis. Prosthetic valve endocarditis occurred in two patients after aortic valve replacement and modified Bentall operation, respectively. The aortic annulus was severely damaged and left ventriculo-aortic discontinuity was found in both cases. We used the freestyle stentless bioprosthesis, which fits well to the destroyed aortic annulus with left ventriculo-aortic discontinuity, because of its flexibility. Postoperative echocardiography revealed excellent hemodynamic results in both cases. Although the long-term results obtained with the freestyle stentless bioprosthesis, such as resistance to bacterial infection, have not been reported, this prosthesis appears to be very useful for treatment of prosthetic valve endocarditis. We expect that this prosthesis might be a option for PVE as an alternative to a homograft.

[A case of tricuspid infective endocarditis in a drug addict]

This report describes a successful operative case of tricuspid infective endocarditis in a drug addict. A 24-year-old man with a history of drug addiction (6 months) complained of general fatigue and high fever. Echocardiography showed a large vegetation attached to the tricuspid valve and severe tricuspid regurgitation. Blood cultures revealed septicemia due to methicillin sensitive Staphylococcus aureus. He was treated for about 1 week with intravenous antibiotics. However, subsequent severe heart failure necessitated emergency operation. The tricuspid valve was replaced with Carpentier-Edwards bioprosthesis because of severe destruction of the tricuspid valve. The postoperative course was uneventful and he has remained free from endocarditis for 15 months after surgery.

Role of endothelial cell denudation and smooth muscle cell dedifferentiation in neointimal formation of human vein grafts after coronary artery bypass grafting: therapeutic implications

OBJECTIVE

To provide better insights into the genesis of neointimal thickening in human vein grafts early after surgery.

DESIGN

Retrospective study.

SETTING

Tertiary referral centre.

SUBJECTS

18 distal anastomotic sites of patent grafts, obtained at necropsy from eight patients who died over differing periods (ranging from two days to nine months) after the procedure.

MAIN OUTCOME MEASURES

Immunohistochemical evaluation of smooth muscle cell phenotype modulation in relation to proliferative activity.

RESULTS

The earliest changes are characterised by loss of surface lining endothelial cells and insudation of blood corpuscular elements admixed with fibrin-platelet thrombus. At sites of injury vimentin positive and actin negative spindle shaped cells appear in the intima, while the related pre-existent media shows focal absence of actin positive smooth muscle cells. Proliferative activity colocalises at these sites. With time distinct neointimal thickening occurs, associated with disappearance of proliferative activity and a phenotypic shift of the smooth muscle cells.

CONCLUSIONS

The observation that luminal endothelial cell denudation, with insudation of the intima with blood elements, occurs in the very early stages suggests that these phenomena are responsible for the observed dedifferentiation of pre-existent smooth muscle cells, known to be a prerequisite for cell proliferation and the evolution of intimal thickening. It is likely, therefore, that platelet released growth factors play a pivotal role, which thus may provide a target for preventive pharmacological intervention.

Cardiac surgery in patients with dialysis-dependent renal disease

This study was designed to evaluate the operative outcome of dialysis patients undergoing cardiac surgery. A retrospective review was performed of 28 consecutive patients with end-stage renal disease dependent on maintenance hemodialysis (n = 26) or peritoneal dialysis (n = 2) who underwent cardiopulmonary bypass (CPB). The operations included isolated coronary artery bypass grafting (CABG) (n = 21), aortic valve replacement (n = 4) and CABG plus aortic valve replacement (n = 3). Seven operations were emergent or urgent. In 23 patients, a heparin-coated (HC) circuit with reduced systemic heparinization was used for CPB. The hospital mortality was 7.1%. Complications occurred in 13 patients (46%). Although thoracotomy for bleeding was required in 3 patients, only 1 had undergone CPB with an HC circuit. There were 7 late deaths. All survivors showed improvement in symptoms and overall functional status. The actuarial survival rates were 78% and 58% at 1 and 4 years, respectively. In the 10 patients with diabetes mellitus, the 4-year survival rate was 50%. In the patients who underwent non-elective surgery, the survival rate was 29%. Cardiac surgery can be performed with increased but acceptable mortality in dialysis patients. Good symptomatic relief can be expected. Surgery should be performed before the general condition deteriorates.

Heparin-coated circuits prevent renal dysfunction after open heart surgery

We examined whether heparin-coated (HC) circuits can improve the operative results in patients with chronic renal insufficiency.

SUBJECTS AND METHODS

Elective cardiac surgery was performed in 24 patients with a serum creatinine (Cr) level of at least 1.5 mg/dl. Uncoated circuits were used in 12 patients, and HC circuits were used in 12 patients. The results of surgery were compared between the two groups.

RESULTS

The mean preoperative Cr concentration was significantly higher in the HC group (2.3 vs 1.8 mg/dl). The heparin doses, protamine dose, and activated clotting times were significantly lower in the HC group. The mean blood loss was also less, although this difference was not significant. The postoperative increase in the Cr level was small in the HC group (2.3-->2.5 mg/dl) compared to that in the noncoated group (1.8-->2.3 mg/dl). Postoperative dialysis was not required in the 5 patients in the HC group with a preoperative Cr clearance less than 20 ml/min.

CONCLUSION

HC circuits and low-dose heparin can be used to maintain renal function after cardiopulmonary bypass, even in patients with severe kidney disease.

Acute acalculous cholecystitis complicated by penetration into the liver after coronary artery bypass grafting

BACKGROUND

Perforation or penetration due to acute acalculous cholecystitis is a rare complication after open-heart surgery. The mortality rate of this disease is high.

METHODS

A 71-year-old woman complained of a sudden onset of right upper abdominal pain with development of peritoneal signs at 21 days after coronary artery bypass grafting. Abdominal ultrasonography and laboratory examination performed at 1 day earlier had revealed no abnormalities. Neither anticoagulants nor antiplatelet agents were administered following the bypass operation. An exploratory laparotomy was performed to locate a presumed embolization to the superior mesenteric artery.

RESULTS

Laparotomy revealed acute acalculous cholecystitis complicated by penetration into the liver, causing a subserosal hematoma. The hematoma had ruptured into the abdominal cavity. A cholecystectomy was performed. The gallbladder wall which was in contact with the liver was necrotic. Most of the gallbladder mucosa was necrotic. Microscopical examination revealed atherosclerosis of the cystic artery which was partially obstructed by thrombus.

CONCLUSIONS

Given the atherosclerotic condition of the cystic artery, hypotension during the bypass in combination with postoperative total parenteral nutrition and hypovolemia may have induced the cystic artery thrombosis. Surgeons who manage patients with cardiovascular disease should be aware of this potentially lethal development.

Coagulofibrinolysis during heparin-coated cardiopulmonary bypass with reduced heparinization

BACKGROUND

We examined the safety of reduced systemic heparinization during heparin-coated cardiopulmonary bypass by measuring coagulofibrinolitic indices, including fibrinopeptide A, which directly reflects fibrinogenesis.

METHODS

Twenty-four patients who had elective cardiac operations were perfused using a circuit coated with covalently bonded heparin. Twelve patients received 300 U/kg of heparin and the remaining 12 patients received 150 U/kg. Blood was obtained for the measurement of thrombin-antithrombin III complexes, fibrinopeptide A, plasmin-alpha 2 plasmin inhibitor complexes, and D-dimer preoperatively; after heparin administration; 10, 60, and 90 minutes after the start of bypass; after protamine administration; and 1, 3, 6, 12, and 24 hours after the end of bypass.

RESULTS

Preoperative, intraoperative, and postoperative variables including postoperative bleeding were not significantly different between the two groups. Further, there were no complications in either group. No significant differences between the two groups were noted for any hematologic index at any time point.

CONCLUSIONS

Reduced systemic heparinization combined with a heparin-coated cardiopulmonary bypass circuit is biochemically and clinically safe but does not reduce postoperative bleeding.