Mechanical Thrombectomy for Postoperative Stroke in a Patient with Acute Aortic Dissection Type A.

Mechanical thrombectomy has been proposed to expand the treatment time window and enhance revascularization. However, it is unclear whether its use can be extended to patients with occlusions in acute aortic dissection, especially the thoracic aorta. A 55-year-old man underwent graft replacement for acute aortic dissection type A. On postoperative day 2, he developed stroke and computed tomography showed occlusion of the right middle cerebral artery. Mechanical thrombectomy was performed by transbrachial approach. Although successful recanalization was achieved, he suffered hemorrhagic stroke. Since there is no other effective treatment and the neurologic outcome with conservative management is poor, we consider mechanical thrombectomy to be a viable therapeutic option for the treatment of postoperative stroke in patients with acute aortic dissection type A. However, further study is warranted regarding the safety of this technique.

Double D Technique: An Innovative Modified Bifurcated Stent Graft Deployment Strategy for an Isolated Common Iliac Artery Aneurysm With a Challenging Renal Artery Anatomy.

PURPOSE: Endovascular aneurysm repair (EVAR) for an isolated common iliac artery aneurysm (iCIAA) sometimes requires a bifurcated stent graft (SG). In EVAR, it is essential to preserve the renal artery (RA). However, this is challenging in cases of anatomical variation. The double D technique (DDT) can be used in anatomically inadequate cases with a commercially approved bifurcated SG. Here, we report the repair of iCIAA in the presence of a challenging RA anatomy, through EVAR using the DDT. CASE REPORT: An 84-year-old woman was diagnosed with a maximal 35-mm diameter left iCIAA and a nonaneurysmal aorta by computed tomography (CT), which also showed that the right RA arose 50-mm above the aortic bifurcation. The DDT was chosen because commercially approved bifurcated SGs typically require a distance of >70 mm from the proximal position to the aortic bifurcation. Postoperative CT showed excellent results with no endoleaks or SG kinking and occlusion, as well as preservation of robust blood flow to the right RA. CONCLUSION: Endovascular aneurysm repair using the DDT can be an alternative option for treatment of iCIAA with a challenging RA anatomy.

Mini open stent grafting with half sternotomy for aortic arch aneurysm.

BACKGROUND: Open stent grafting is an alternative of graft replacement and thoracic endovascular aortic repair for aortic arch aneurysm. We have performed open stent grafting with half sternotomy (mini-OSG) to reduce in-hospital stay and recovery time of patients and herein report seven cases of mini-OSG for aortic aneurysm and dissection. CASE PRESENTATION: The patients' mean age was 66 years. Cardiopulmonary bypass was performed conventionally, and an open stent graft was inserted via an aortotomy on the aortic arch during circulatory arrest. No mortality occurred. The mean operation time was 387 min, and the mean blood loss was 587 ml. The patients were weaned from the ventilator 7.1 h postoperatively. No pseudoaneurysm or endoleakage was observed during the 2- to 20-month follow-up. CONCLUSIONS: Mini-OSG might be less invasive, although further studies and intensive follow-up are needed.

Hemolytic characteristics of three suctioning systems for use with a newly developed cardiopulmonary bypass system.

INTRODUCTION: We have been developing a closed-circuit cardiopulmonary bypass (CPB) system ("Dihead CPB") for application during coronary artery bypass grafting (CABG) and valve surgery. To strive for minimal hemolysis during Dihead CPB, we compared the hemolysis caused by three different suction systems and performed a clinical study with the newly applied suction system. MATERIALS & METHODS: We evaluated the hemolysis caused by roller-pump suction, the SmartSuction® Harmony® and wall suction systems with respect to suction speed and compared the systems by means of in vitro studies. A clinical study was also performed on 15 volunteers to assess hemolysis and the adequacy of the newly applied suction system with Dihead CPB. RESULTS: Pressure inside the suction cannula was -22.5 ± 0.1 mmHg at a maximum flow of 1.5 L/min for roller-pump suction and -43.4 ± 0.1 mmHg at -150 mmHg of the set vacuum pressure of wall suction. With the SmartSuction, the pressure inside the cannula varied from -76.3 ± 1.0 to -130.3 ± 1.5 mmHg, depending on suctioning conditions. Suction speed (to suction 50 ml of blood) was fastest with the SmartSuction (69.7 ± 3.58 s) whereas, with roller suction, it was 117.3 ± 8.47 s and with wall suction 96.9 ± 7.10 s. The SmartSuction had the highest hemolysis rate (2.00 ± 0.33%) vs. 0.61 ± 0.10% for roller suction and 0.41 ± 0.11% for wall suction (p<0.001). The clinical study with wall suction showed no significant increase in plasma free hemoglobin during or after CPB compared with before surgery. CONCLUSIONS: Wall suction had less hemolysis than roller suction or the SmartSuction in the in vitro study and the clinical study with wall suction showed efficient suction speed and acceptable hemolysis, suggesting that Dihead CPB with wall suction is feasible for CABG.

[Successful Treatment with Aortic Stent Graft and Transcatheter Embolization for Bronchial Artery Aneurysm].

We report a case of bronchial artery aneurysm (BAA) successfully treated with a combination of transcatheter embolization and stent graft. A 50-year-old woman was referred to our hospital for further examination of a hemispherical bulging lesion on the middle esophagus detected by gastroscopy. Computed tomography (CT) revealed BAA with a 15 mm-diameter arising from the descending aorta on the left side of the esophagus. We performed transcatheter embolization combined with a stent graft because of a short neck. Postoperative course was uneventful. Follow-up CT showed complete isolation of the blood flow into the BAA. BAA is rare and often found incidentally by diagnostic imaging as shown in our case. Prompt treatment with complete isolation of blood inflow is required because the rupture of BAA is life-threatening.

Open stent graft repair with upper-half Sternotomy for blunt thoracic aortic injury: a case report.

BACKGROUND: Thoracic endovascular aortic repair is now widely applied to the treatment of blunt aortic injury. However, its long-term outcomes remain unclear. Endoleakage and migration might occur in the long term, especially when younger patients undergo endovascular aortic repair. In open stent grafting, the proximal end of the open stent graft is directly sutured to the native aorta, which may reduce the risk of endoleakage and migration. We applied open stent grafting to the treatment of blunt aortic injury in the subacute phase and herein report the patient's clinical course. CASE PRESENTATION: A 20-year-old man with a developmental disorder collided with a steel tower while skiing. He was transferred to our hospital by helicopter. X-ray examination and computed tomography revealed fractures of left humeral head and femoral neck and aortic isthmus dissection. We did not perform an acute-phase operation because of the presence of multiple trauma and instead performed open stent grafting with an upper-half sternotomy 42 days after the injury. He recovered uneventfully without psychological problems other than his preexisting developmental disorder. No endoleakage or aneurysm was observed during an 18-month follow-up period. CONCLUSIONS: Open stent grafting might be an alternative to open surgery and thoracic endovascular aortic repair for blunt chest trauma, although intensive follow-up is needed.

Biventricular support using a centrifugal pump in a 6 year old with fulminant myocarditis.

We experienced a case of ventricular assist with both a pulsatile-flow and a continuous-flow pump in a pediatric patient, and herein report the clinical course and characteristics of the pumps. A 6-year-old female was diagnosed with fulminant myocarditis and transferred to our hospital for mechanical support. After 12 days of extracorporeal membrane oxygenation, we implanted a left ventricular assist device (LVAD) and a right ventricular assist device (RVAD) using centrifugal Gyro pumps with a membrane oxygenator in a paracorporeal fashion. The membrane oxygenator was removed on postoperative day (POD) 4, and the patient was weaned from the respirator on POD 6. The LVAD was exchanged on POD 13 and 17, and the RVAD was exchanged on POD 14 because of thrombus formation inside the pumps. The RVAD was removed on POD 25. On POD 32, the patient experienced cerebral infarction and the centrifugal Gyro pump was switched to an extracorporeal pulsatile pump. No thromboembolic event occurred after pump conversion, although continuous administration of vasodilators was required to avoid hypertension. She underwent successfully heart transplantation in the USA after 8 months of ventricular support. A centrifugal pump is considered useful for pediatric patients, as pump flow and blood pressure can be relatively easily controlled in the postoperative acute phase compared with the pulsatile pump. However, special care should be taken to monitor for thrombus formation when support length becomes longer than 13 days, and a switch to a pulsatile pump should be considered once the hemodynamic status stabilizes.

Pseudoaneurysm of graft-graft anastomosis of a hand-sewn branched graft: a case report.

BACKGROUND: Pseudoaneurysm of graft-graft anastomosis is an extremely rare but potentially fatal complication after thoracic aorta replacement with a prosthetic graft. We report a case of pseudoaneurysm at the graft-graft anastomosis of a hand-sewn branched graft. CASE PRESENTATION: A 65-year-old man underwent total arch replacement with a hand-sewn branched graft for Stanford type A acute aortic dissection 22 years ago. During follow-up, serial CT scans showed a pseudoaneurysm on the branched graft which warranted reintervention. Surgical repair involved direct suture of multiple bleeding points which were found at the sites of the hand-sewn branches anastomosis. The postoperative course was uneventful, and no signs of bleeding were observed by CT after the reoperation. CONCLUSIONS: Long-term follow-up is essential to detect late complications at the site of hand-sewn anastomosis.

Patch detachment after mitral valve repair with posterior leaflet augmentation: a case report.

Mitral valve (MV) repair is indicated for patients with severe MR. We report a case of acute MR caused by patch detachment after posterior leaflet augmentation in MV repair. A 65-year-old male underwent MV repair with posterior leaflet augmentation and coronary artery bypass graft 1 month prior to this study. An inverted T-shaped incision was made on the posterior mitral leaflet (PML), and a piece of autologous fresh pericardium was sewn in the PML defect. Seven days after hospital discharge, he started feeling chest pain and presented with pulseless electrical activity. Ultrasonic cardiography showed severe mitral regurgitation (MR), which was suggestive of acute MR. We performed emergency reoperation. The edge of the autologous pericardial patch was detached from the anterior papillary muscle, and MV replacement was performed. He was discharged from the hospital 55 days after the reoperation and returned to his normal daily life. We conclude that avoidance of tension focalization during MV repair may be important.

Pseudoaneurysm fistulated into the right atrium after double valve replacement.

We discuss a rare case of an ascending aorta pseudoaneurysm fistulating into the right atrium following prior aortic and mitral valve replacement. Transthoracic echocardiography and computed tomography revealed a pseudoaneurysm of the ascending aorta attached to the right atrium with fistulous communication. The pseudoaneurysm arose from the center of the former aortotomy. Emergency remedian sternotomy was performed without aneurysmal injury and with exposure of the left femoral artery and femoral vein. Aneurysmal resection and ascending aorta repair were performed without complication. Exposing peripheral vessels, and initiating cardiopulmonary bypass only after reentry, might be effective in resternotomy to approach ascending aorta pseudoaneurysms.

[Graft Replacement for Adult Aortic Coarctation].

Case 1:a 47-year-old woman who complained of sweating, finger tremor, and chest pain was diagnosed with coarctation of the aorta and hyperthyroidism. She had been diagnosed with hypertension at 25 years of age but had not undergone further examination. Graft replacement was performed without cardiopulmonary or temporary bypass. Case 2:a 30-year-old woman was diagnosed with coarctation during infertility treatment. Although health screening had revealed hypertension 8 years previously, no further assessment took place. She underwent graft replacement with partial cardiopulmonary bypass. In both cases, we conducted a clamp test to decide whether cardiopulmonary or partial bypass was necessary for graft replacement. Blood pressure discrepancy between upper and lower extremities disappeared immediately after surgery, and no ischemic complications were observed. Hypertension in young adults should prompt further scrutiny for anatomical disorders such as coarctation. A clamp test is considered helpful regarding the surgical approach to graft replacement for coarctation.

Early and midterm results of transapical and right axillary artery cannulation for acute aortic dissection.

BACKGROUND: We combined transapical cannulation and right axillary artery cannulation in the repair of acute type A aortic dissection in order to reduce mortality and morbidity in the presence of risk of malperfusion. Early and midterm outcomes were evaluated. METHODS: Between October 2009 and March 2012, 23 aortic dissection patients (age, 54.3 ± 13.5 years) received graft replacement using a combination of transapical and right axillary artery cannulation. Preoperative malperfusion was present in 16 patients (69.6%). Cardiopulmonary bypass was initiated with axillary artery cannulation applied via the right axilla and right atrial drainage, then aotric cannulation applied via the left ventricular apex. We retrospectively investigated mortality and morbidity as well as cardiac function, which were evaluated echocardiographically during hospitalization and once a year postoperatively. RESULTS: All patients received total arch replacement. In-hospital mortality was 4.3%, and no patient developed intraoperative malperfusion. Intraoperative stroke occurred in one patient (4.3%), and three patients (13.0%) suffered from delayed stroke (10-24 days). These delayed strokes might have resulted from cardiogenic thrombus, although no intracardiac thrombus was found. Mean ejection fraction was 66.1 ± 10.9% in the early postoperative period and 73.1 ± 8.7% midterm. There was no left ventricular asynergy or intracardiac thrombus seen on either early or midterm echocardiography. CONCLUSION: Transapical cannulation with right axillary artery cannulation is a safe and effective procedure that can reduce operative risk associated with aortic dissection. Although transapical cannulation does not appear to impair cardiac function, it may confer a risk of delayed stroke.

Characteristics of cardiac allograft vasculopathy induced by immunomodulation in the miniature Swine.

PURPOSE: We aimed to develop swine cardiac transplantation model for study of cardiac allograft vasculopathy (CAV) and to characterize the mechanisms of its formation. METHODS: Heterotropic cardiac transplantation was performed in swine leukocyte antigen mismatched miniature swine, and CAV was induced by immunomodulation by cyclosporine A (CyA). Histology and immunohistochemistry were performed to identify cellular components of CAV. Fluorescence in situ hybridization (FISH) was developed for detection of 1 and Y-chromosome for identification of cell origin in the female donor to the male recipient heart transplantation model. RESULTS: CAV was successfully developed by immunomodulation of CyA. Severity of CAV revealed more prominent in the distal epicardial coronary arteries than proximal coronary arteries. Phenotype of the SMCs proliferated in the intimal thickening of CAV were mostly embryonal/secretory type. Our new chromosome specific probes for FISH method were useful for discrimination of sex of each cell, and proliferated SMCs were revealed to be mainly donor origin. CONCLUSION: CAV mimicking human heart transplantation can be developed by appropriate immunomodulation in the swine. In swine CAV, proliferated SMCs seen in the intimal thickening were demonstrated to be from the donor origin.

[Left atrium thrombus after mitral valve replacement presented with syncope; report of a case].

Left atrial free ball thrombus (LABT) after mitral valve replacement (MVR) is very rare, and sudden death may occur by thrombus impaction to the mitral valve orifice. A 81-year-old woman who underwent MVR and tricuspid annuloplasty ten years ago presented with syncope. She was admitted to a hospital, and echocardiography revealed a LABT. When she took sitting position, she fainted. The free ball thrombus possibly impacted mitral valve orifice. She was transferred to our hospital and an emergent operation was performed. There was a LABT of 4 cm in diameter, which was removed. Postoperative course was uneventful. There are 12case reports which described LABT after MVR, and anticoagulant therapy was insufficient in most of those cases. Strict anticoagulant therapy is important to prevent left atrial thrombus after MVR.

Pericoronary pseudotumor caused by helicobacter cinaedi.

Cardiac tumors and tumor-like lesions are uncommon; most are true neoplasms. We here report a case of a pericoronary tumor-like lesion surrounding the right coronary artery in a 39-year-old man who presented with fever and chest pain. Although clarithromycin was administered for 1 week, his fever persisted. Helicobacter cinaedi (H. cinaedi) was isolated from blood cultures and found to be sensitive to ceftriaxone. A computed tomography scan showed a tumor-like lesion with no (18)F-fl uorodeoxyglucose uptake surrounding the right coronary artery. After administration of ceftriaxone, the tumor-like lesion diminished in size according to meticulous computed tomography examinations. We therefore concluded that it was caused by H. cinaedi infection. The patient has been followed up closely for 1 year and remains asymptomatic.

Delayed esophageal perforation secondary to thoracic aortic aneurysm rupture in a patient with human immunodeficiency virus infection.

A 65-year-old man infected with human immunodeficiency virus underwent emergency surgery for rupture of a mycotic descending thoracic aneurysm. The aneurysm was replaced with a prosthetic graft wrapped with omentum. Esophageal perforation occurred 3 weeks after surgery. The patient's condition remained stable, and we adopted a conservative treatment. The esophageal fistula had not healed completely and a biopsy of the scar revealed gastric cancer. We performed a distal gastrectomy, Roux-Y reconstruction, and enterostomy for enteral feeding. Follow-up endoscopy revealed healing of the fistula, and the patient was eventually discharged. We managed this potentially fatal complication with minimally invasive treatment.

Prosthesis-sparing aortic root replacement following aortic valve replacement.

Reoperation on the aortic root is considered to be challenging because of high hospital mortality. Prosthesis-sparing aortic root replacement, in which the aortic prosthesis is preserved during reoperation, and could avoid passing sutures through the weakened aortic annuls after the initial prosthesis has been removed. We report 3 cases of prosthesis-sparing aortic root replacement. Prior procedures were aortic valve replacement and the Bentall operation 14 to 35 years previously. Postoperative courses were uneventful, with no signs of pseudoaneurysm or valve malfunction observed during follow-up periods of 93 to 360 days.

Platelet function during cardiopulmonary bypass using multiple electrode aggregometry: comparison of centrifugal and roller pumps.

Blood trauma may be lower with centrifugal pumps (CPs) than with roller pumps (RPs) during cardiopulmonary bypass (CPB), because, unlike RPs, CPs do not compress the tubing, and shear stress is considered lower in CPs than in RPs. However, relative platelet function remains unclear. Using multiple electrode aggregometry (MEA), we compared platelet function with CP and RP. Ten swine underwent CPB for 3 h, with five weaned off using CP and five using RP. Platelet function was measured using MEA, as were hemoglobin concentration and platelet count, before sternotomy, after heparin infusion, 30 min and 3 h after starting CPB, after protamine infusion, and 60 min after stopping CPB. Platelet activation was initiated with adenosine diphosphate (ADP), arachidonic acid (AA), and thrombin receptor-activating protein 6 (TRAP). Fibrinogen, platelet factor 4 (PF4), and ß-thromboglobin (ß-TG) concentrations were measured before sternotomy and 60 min after stopping CPB. In the CP group and using ADP, aggregation was significantly reduced 30 min (P = 0.019) and 3 h (P = 0.027) after starting CPB, recovering to baseline 60 min after CPB was stopped. In the RP group, aggregation was significantly decreased 30 min (P = 0.007) and 3 h (P = 0.003) after starting CPB and after protamine administration (P = 0.028). With AA, aggregation significantly decreased 30 min after starting CPB in both the CP (P = 0.012) and RP (P = 0.016) groups, slightly increasing 3 h after starting CPB and after protamine infusion, and recovering to baseline 60 min after CPB cessation. With TRAP, aggregation in the CP and RP groups decreased 30 min after starting the pump, although changes were not significant; aggregation gradually recovered after 3 h and returned to baseline 60 min after the pumps were stopped. There were no significant differences at all sampling points of MEA. In both groups, fibrinogen, PF4, and ß-TG concentrations were similar 60 min after pump cessation and before sternotomy. Platelet function, evaluated with MEA, was lowest 30 min after CPB was started but did not decrease over time in either group. As assessed by MEA, platelet function using CP and RP did not differ significantly. Platelet dysfunction was caused mainly by initial contact with foreign materials and may not be dependent on type of pump.

Surgical outcomes of acute type A aortic dissection in elderly patients.

BACKGROUND: Age is still considered a risk factor in the repair of acute type A aortic dissection. Instead of total arch replacement, we performed hemiarch or partial arch replacement with intimal tear exclusion to reduce death in elderly patients and evaluated early-term and midterm outcomes. METHODS: From January 2004 to April 2012, 59 patients older than 70 years (mean age, 77.0±4.3 years) underwent emergency operations for acute type A aortic dissection at our institution. We performed hemiarch, partial arch, or total arch replacement, according to the location of the primary entry tear. The characteristics, surgical procedures, and early-term and midterm outcomes of these patients were reviewed. RESULTS: We performed hemiarch replacement in 47 patients, partial arch replacement in 4, and total arch replacement in 8. The primary entry site was excluded in 56 of 59 patients (94.9%). In-hospital mortality was 6.8%, and neurologic impairment occurred in 25.4%. We obtained midterm outcomes for 55 of 59 patients, with a mean follow-up period of 43.9±23.7 months. Fourteen patients died, two of these of aortic-related causes. One patient required repeat aortic operation for rupture of a pseudoaneurysm. Follow-up computed tomography imaging was done in 28 of 55 patients during the 12 months after the operation. No significant difference was noted in the increase in maximal aortic diameter between patients with and without residual dissection. CONCLUSIONS: In-hospital mortality was 6.8%; relatively low compared with previous reports. Hemiarch and partial arch replacement with entry tear exclusion may reduce deaths associated with acute type A aortic dissection repair in elderly patients, without increasing the risk of reoperation and aortic-related death.

Tracheo-Bronchial Obstruction and Esophageal Perforation after TEVAR for Thoracic Aortic Rupture.

A 67-year-old man was referred to our hospital for an ascending aortic aneurysm, thoracoabdominal aortic aneurysm and aortic regurgitation. Graft repair of the thoracic aortic arch and aortic valve replacement was given priority and completed, however he developed descending aortic rupture before the second scheduled surgery, and endovascular stent grafting was performed. He subsequently developed tracheobronchial obstruction and esophageal perforation. The patient underwent urgent esophagectomy and enterostomy with continuity later reestablished. However, he died of sepsis 5 months after surgery. Despite the less invasive nature of endovascular treatment, esophageal perforation can nevertheless occur and postoperative vigilance is well warranted.