[Distal Stent Graft-induced New Entry after Total Arch Replacement for the Aortic Dissection:Report of a Case].

A 73-year-old man after total arch replacement with open stent graft (OSG) technique for Stanford type B aortic dissection was found to have expanding descending aortic aneurysm. Contrast-enhanced computed tomography (CT) showed distal stent graft-induced new entry (distal SINE). We successfully performed additional thoracic endovascular aortic repair (TEVAR). The determinants of distal SINE are reported to be excessive distal oversizing and spring back force on the distal end of the stent graft, which might make the stress for descending aorta. We also found that the angle between distal end of the stent graft and the horizontal line of the body was changed. The angle when distal SINE occurred was smaller than that of when it was placed. Appropriate size selection and positioning of stent graft might reduce the risk of distal SINE events.

Ventriculitis after emergent arch aneurysm surgery.

A 72-year-old man was referred to our institution because of an arch aneurysm and acute aortic dissection (thrombosed Stanford type A). Anti-impulse therapy was initiated. He developed a high fever after admission. Blood culture was negative. Five days after admission, he developed back pain. Thoracoabdominal computed tomography revealed a new low-density area from the distal arch to the descending aorta. We performed emergent total arch replacement. Although we discontinued all sedative drugs after surgery, coma continued. Brain magnetic resonance imaging with diffusion-weighted imaging revealed ventriculitis with brain infarction. After antimicrobial therapy was started, his consciousness level improved. Ventriculitis should be suspected when disturbance of consciousness continues longer than we predict after emergent arch aneurysm surgery. Delay in diagnosis can lead to a life-threatening condition.

[Simultaneous Transapical Transcatheter Aortic Valve Implantation and Coronary Artery Bypass Grafting;Report of a Case].

Coronary artery disease(CAD) is often found concurrently in patients presenting with severe aortic stenosis(AS). Surgical aortic valve replacement(SAVR) and coronary artery bypass grafting(CABG) were usually selected with such patients. Recently, transcatheter aortic valve implantation (TAVI) is considered as a less invasive and more feasible treatment option in high-risk AS patients. A 74-year-old woman admitted due to acute myocardial infarction and treated with percutaneous coronary intervention revealed severe AS. Because of her comorbidities, concomitant transapical TAVI and CABG were performed with an excellent clinical course.

[Native Aortic Valve Endocarditis Caused by Nocardia asteroides;Report of a Case].

Infection by Nocardia sp. is rare and usually affects immuno-depressed patients, such as those receiving chemotherapy and long-term steroid therapy. Cardiac involvement is uncommon and usually occurs as endocarditis. We present a case of native aortic valve endocarditis caused by Nocardia asteroides. Aortic valve translocation method was chosen because of extensive root infection with major disruption of the aortic annulus. Over 2 years after the surgery, there is no recurrence and no enlargement of the aortic annulus.

[Redo Coronary Artery Bypass Grafting Through Left Thoracotomy in Patient with Patent Left Internal Thoracic Artery Graft;Report of a Case].

A 61-year-old man was admitted because of unstable angina. The patient had a history of CABG [LITA-left anterior descending artery(LAD), aorta-saphenous vein graft(SVG)-posterolateral branch (PL)-diagonal branch (D1)]4 years ago. Coronary angiography revealed an occlusion of old SVG at proximal anastomosis site and a stenosis of native high lateral artery (HL). To reduce the risk of cardiac injury and damage to the patent grafts due at sternal reentry, we performed redo CABG through left thoracotomy. The proximal site of SVG was anastomosed to descending aorta using automated proximal anastomosis system. The SVG was anastomosed to the HL and old SVG in a sequential mode. Postoperative course was uneventful and the patient was discharged on postoperative day 14. Redo CABG through left thoracotomy provides safe and effective surgical approach in patient who requires revascularization of left circumflex territory.

[Intercostal lung hernia diagnosed by computed tomography images under the semilateral position].

A 62-year-old man developed a swelling of the left anterior chest after surgery for a thoracic aortic aneurysm. Chest computed tomography (CT) images in the left semilateral position, which were obtained when his intrathoracic pressure was elevated through the Valsalva maneuver, showed a herniated lung with a fragile site of the surgical wound in the chest wall as a hernial orfice, as well as a hernial sac in the posterior of the greater pectoral muscle. A diagnosis of traumatic hernia occurring after thoracotomy was made, for which radical surgery involving direct closure was performed.

[Total arch replacement for spontaneous rupture of the thoracic aorta;report of a case].

A 75-year-old man without history of trauma and aortic aneurysm presented with chest discomfort. A computed tomography (CT) revealed massive mediastinal hematoma without intimal flap in the aorta. Under hypothermic circulatory arrest, total arch replacement was performed. A transmural tear was found just distal to the left subclavian artery. Aortic dissection was not found macroscopically. When we encounter massive hematoma in the anterior mediastinum or the left thoracic cavity, spontaneous rupture of the thoracic aorta should be suspected, and emergency operation should be performed via optimal surgical approach.

Left Ventricular Pseudoaneurysm With a Bead-Like Appearance After Myocardial Infarction: The Utility of Cardiac Computed Tomography.

A left ventricular pseudoaneurysm is a rare but life-threatening complication after myocardial infarction. Because untreated pseudoaneurysms have a 30%-45% risk of rupture, surgery is the preferred therapeutic option. However, its diagnosis is sometimes challenging, as a pseudoaneurysm presents with non-specific symptoms that can mimic myocardial infarction or heart failure. We report a male patient with a history of aortic dissection surgery who presented with recurrent chest pain probably due to acute coronary syndrome. Transthoracic echocardiography revealed a cavity at the apex of the left ventricle, indicating a mechanical complication after myocardial infarction. As the coronary angiography was considered difficult because of the patient's anatomical problem, contrast-enhanced computed tomography (CT) was performed. CT angiography revealed multiple nodular cavities continued from within the left ventricle. It seemed that the pseudoaneurysm was formed in stages in the adherent pericardium after myocardial infarction, resulting in a bead-like appearance. Emergent pseudoaneurysmectomy and left ventricular wall repair were performed, and the patient was discharged without any complications. This case illustrates the utility of cardiac CT to establish the diagnosis of left ventricular pseudoaneurysm and coronary artery atherosclerosis.

[Preferable surgical approaches to the aortic root-arch in patients with functioning tracheostomy].

Preferable surgical approaches to aortic diseases occurring between the aortic root and the arch in patients with functioning tracheotomy or permanent tracheostomy are described for securing adequate exposure and avoiding postoperative mediastinitis. Case 1: A 41-year-old man with Marfan syndrome presented with chronic type A thrombosed aortic dissection and severe aortic valve regurgitation. He had had a functional tracheostomy for managing respiratory function due to traumatic spinal cord damage. The heart and the ascending aorta were shifted to the right side of the chest and showed a significant counterclockwise rotation. Therefore, the reverse L-figure approach of a right-sided 3rd intercostal anterior thoracostomy and lower midline sternotomy was performed for Bentall operation. Case 2: A 76-year-old woman presented with thoracic aortic aneurysm of 11 cm in diameter. She had had a permanent tracheostomy with total laryngectomy. Therefore, cram shell approach was performed for total arch replacement. The 2 cases had no postoperative mediastinitis. These approaches are recommended for aortic diseases occurring in the ascending aorta or the aortic arch in patients with functioning tracheotomy.

Incidental retroaortic innominate vein in a patient with acute aortic dissection.

BACKGROUND: Retroaortic innominate vein is a rare anomaly. It has been reported in patients with congenital anomalies such as Tetralogy of Fallot or right aortic arch. However, isolated retroaortic innominate vein is quite rare. CASE PRESENTATION: A 63-year-old man was transferred to our institution because of Stanford type A acute aortic dissection. Incidentally, we noticed that the left innominate vein coursed under the aortic arch and was directed into the superior vena cava on computed tomography. We performed emergent hemiarch replacement. CONCLUSIONS: Attention must be paid to the cannulation site for venous uptake and the method of myocardial protection.

Critical left coronary main trunk stenosis, chronic occluded right coronary artery, left subclavian artery occlusion, severe aortic regurgitation and porcelain aorta in a patient with aortitis.

BACKGROUND: Coronary involvement is rare but can be critical in patients with aortitis. Although cardiac ischemia can be resolved by coronary artery bypass grafting (CABG), patients complicated with cardiac ischemia, calcified aorta, and valve insufficiency pose difficult problems for surgeons. CASE PRESENTATION: A 71-year-old woman was referred to our institution because of unstable angina. She had been previously diagnosed with aortitis and left subclavian artery occlusion. Contrast-enhanced computed tomography revealed severe left coronary main trunk stenosis, right coronary artery occlusion, and porcelain aorta. Ultrasonic echocardiogram showed severe aortic regurgitation. We performed emergent coronary artery bypass grafting, aortic valve replacement and ascending aorta replacement under hypothermic circulatory arrest. CONCLUSIONS: The technique of circumferential calcified intimal removal and reinforcement with felt strips was effective for secure anastomosis. Unilateral cerebral perfusion from the right subclavian artery enabled good visualization and sufficient time to perform distal anastomosis.

Aorto-carotid bypass for type A acute aortic dissection complicated with carotid artery occlusion: no touch until circulatory arrest.

The surgical management for type A acute aortic dissection complicated with carotid artery occlusion remains controversial. Between December 2012 and June 2017, 127 patients who presented with type A acute aortic dissection were operated on in our hospital. Of this group, nine (7.08%) patients had cerebral malperfusion due to carotid artery occlusion. The site of occlusion was innominate artery (n = 5) or right carotid artery (n = 4). Preoperative neurological symptoms were left hemiplegia (n = 1), left hemiparesis (n = 3) and seizure (n = 2). Preoperative consciousness level was Japan Coma Scale 2 (n = 6), 20 (n = 2), or 200 (n = 1). The procedure consisted of hemiarch replacement (n = 4) or total arch replacement (n = 5). Aorto-carotid bypass was performed in all patients under hypothermic circulatory arrest. The time from onset of symptoms to operating room was 7.2 ± 2.4 h. Hospital mortality was 0%. Left hemiplegia and left hemiparesis improved significantly. Japan Coma Scale was 0 in all patients at discharge. Overall survival at 24 months after operation was 100%. Aorto-carotid artery bypass for type A acute aortic dissection with carotid artery occlusion is the treatment of choice in these high-risk patients. Our strategy of 'no touch until circulatory arrest' may contribute to neurological improvement.

Was the internal thoracic arterial graft selection for coronary artery bypass grafting appropriate in a patient with neurofibromatosis-1?

Neurofibromatosis type 1, also called von Recklinghausen's disease, is a hereditary congenital disorder that affects tissues of neuroectodermal or mesodermal origin. This disease has various manifestations, including pigmented skin lesions, cutaneous neurofibromas, skeletal abnormalities, and tumors of the central/peripheral nervous and gastrointestinal systems, and vascular abnormalities. Because of vasculopathy, part of the vessel wall may be replaced by neurofibromatosis tissue. Involvement of the internal thoracic artery is, however, extremely rare. Off-pump coronary artery bypass grafting using the left internal thoracic artery was performed for coronary arterial disease in a patient with neurofibromatosis, and the residual left internal thoracic artery vessel pathology was investigated. The left internal thoracic artery vessel showed intimal proliferation, medial thinning, and fragmentation of elastic tissue. However, these findings were not typical for von Recklinghausen's neurofibromatosis. Internal thoracic artery graft selection was feasible for coronary artery bypass grafting in a patient with neurofibromatosis type 1.

Feasibility of a new hollow fiber silicone membrane oxygenator for long-term ECMO application.

Currently in United States, there are no clinically-applicable hollow fiber extracorporeal membrane oxygenation (ECMO) oxygenators available. Therefore, our laboratory is in the process of developing a silicone hollow fiber membrane oxygenator for long-term ECMO usage. This oxygenator incorporates an ultrathin silicone hollow fiber. At this time, a specially-modified blood flow distributor (one chamber distributor) is centered in the module to prevent blood stagnation. An ex vivo long-term durability test for ECMO was performed using a healthy miniature calf for 2 weeks. Venous blood was drained from the left jugular vein of a calf, passed through the oxygenator and infused into the left carotid artery using a Gyro C1E3 centrifugal blood pump. A successful 2-week ex vivo experiment was performed. The O2 and CO2 gas transfer rates were maintained at the same value of 40 m/min at a blood flow rate of 1 L/min flow and V/Q=3 (V=gas flow rate; Q=blood flow rate). The plasma free hemoglobin was maintained around 5 mg/dl. After the experiment, no blood clot formation was observed in the module and no abnormal necropsy findings were found. These data suggest that the performance of this newly-improved oxygenator was stable, reliable, and acceptable for long-term ECMO.

Hemolytic characteristics of oxygenators during clinical extracorporeal membrane oxygenation.

A connection was previously reported between the hemolytic characteristics associated with oxygenators and the pressure drop measurements in the blood chamber under experimental conditions simulating their use in cardiopulmonary bypass. We examined this association during extracorporeal membrane oxygenation (ECMO) conditions. Three oxygenators for ECMO or pediatric cardiopulmonary bypass (Menox EL4000, Dideco Module 4000, and Mera HPO-15H) were evaluated. Fresh blood from healthy Dexter strain calves anticoagulated with citrate phosphate dextrose adenine solution was used. The blood flow was fixed at 1 L/min, similar to that in ECMO. The Normalized Index of Hemolysis for Oxygenators (NIHO) has been modified according to the American Society of Testing and Materials standards, as was previously reported. The NIHO value was the lowest in the Menox (0.0070+/-0.0009) and increased from Menox to Dideco (0.0113+/-0.0099) to Mera (0.0164+/-0.0043); however, there were no significant differences among the oxygenators. This NIHO value has a close correlation to the pressure drop. In conclusion, this evaluation method is also applicable to comparison of the biocompatibility performance of different types of clinically available oxygenators for ECMO.

Physiological adaptation to a nonpulsatile biventricular assist system.

Physiological adaptation of the recipient to a nonpulsatile biventricular assist system (NPBVAS) is not well understood. The aim of this study is to evaluate the physiological adaptation of experimental animals after NPBVAS implantation. Since May 2001, four long-term NPBVAS implant experiments in calves were performed. The blood gas and hemodynamic data were analyzed retrospectively. An additional prospective experiment was performed to confirm retrospective findings. All calves (n = 5) lived longer than 5 weeks without complication. In retrospective analysis, there was not a correlation between the O2 content and total blood flow in the pulmonary artery during the 1st postoperative week, but they began to correlate within the 2nd postoperative week. Then, there was a strong correlation after the 3rd postoperative week (r = 0.753). In the prospective experiment, O2 content related to total pulmonary flow after 2 weeks (r = 0.732) was the same as in the retrospective study. Most of the hemodynamic parameters studied became normalized after 14 days. In addition, easier controllability of the blood pumps was demonstrated after the 2nd postoperative week in all five experiments. Experimental results suggested that the native healthy heart accepted NPBVAS by reducing its cardiac output in 2 weeks. In addition, complicated control of the BPVAS was not necessary after 2 weeks of implantation. These results demonstrate the possibility of physiological adaptation to the NPBVAS being established within 2 postoperative weeks.

In vivo evaluation of the NEDO biventricular assist device with an RPM dynamic impeller suspension system.

Since 1995, the Baylor College of Medicine group has been developing the NEDO Gyro permanent implantable (PI) pump. The Gyro PI pump has achieved outstanding results up to 284 days with no thrombus formation during the left ventricular assist device (LVAD) animal experiments. However, in biventricular assist device (BVAD) animal experiments, thrombus formation did occur. An in vitro experiment showed the reason for thrombus formation was caused by the missed magnetic balance between the impeller and the actuator. On the basis of this result, the revolutions per minute (RPM) impeller suspension system was developed. Six long-term animal studies were performed in bovine models. Survival periods were 90, 80, 60, 51, 48, and 37 days, respectively. No thrombus was observed in the pumps with the exception of one right pump. In that experiment, the thrombus formation may have occurred when the pump had a low flow because of outflow kinking. In this article, the antithrombogenic effect of this RPM impeller suspension system will be discussed.

Preclinical evaluation of a new hollow fiber silicone membrane oxygenator for pediatric cardiopulmonary bypass: ex-vivo study.

Based on the results of many experimental models, a hollow fiber silicone membrane oxygenator applicable for long-term extracorporeal membrane oxygenation (ECMO) was developed. For further high performance and antithrombogenicity, this preclinical model was modified, and a new improved oxygenator was successfully developed. In addition to ECMO application, the superior biocompatibility of silicone must be advantageous for pediatric cardiopulmonary bypass (CPB). An ex vivo short-term durability test for pediatric CPB was performed using a healthy miniature calf for six hours. Venous blood was drained from the left jugular vein of a calf, passed through the oxygenator and infused into the left carotid artery using a Gyro C1E3 centrifugal pump. For six hours, the O2 and CO2 gas transfer rates were maintained around 90 and 80 ml/min at a blood flow rate of 2 L/min and V/Q=3, respectively. The plasma free hemoglobin was maintained around 5 mg/dl. These data suggest that this newly improved oxygenator has superior efficiency, less blood trauma, and may be suitable for not only long-term ECMO but also pediatric CPB usage.

A Case of Acute Aortic Dissection with Intimal Tear Found at 1 cm Above Previous Aortotomy.

Although it is rare, acute aortic dissection after cardiac surgery predisposes the patients to critical condition such as rupture, tamponade and death. Prompt diagnosis and treatment is mandatory for this fatal complication. We present our case in which acute aortic dissection occurred 7 years after aortic valve replacement.

Effect of landiolol hydrochloride after off-pump coronary artery bypass.

OBJECTIVES: many studies have shown that oral beta blockers reduce the incidence of atrial fibrillation after coronary artery bypass. The goal of this study was to determine whether landiolol, an intravenous beta blocker, reduces the incidence of atrial fibrillation after off-pump coronary artery bypass. METHODS: 39 consecutive patients were given landiolol after coronary artery bypass, and 20 who were not given landiolol served as a control group. Landiolol was intravenously administered at 1 µg.kg(-1).min(-1) in the intensive care unit. RESULTS: the mean dose of landiolol was 2.3 ± 1.2 1 µg.kg(-1).min(-1). The incidence of atrial fibrillation during intensive care unit stay was significantly lower in the landiolol group compared to the control group: 2.6% (1/39) vs. 20% (4/20). Heart rate after landiolol administration was significantly lower than that before administration, whereas landiolol had no effect on blood pressure. C-reactive protein and creatine kinase levels 7 days after surgery were significantly lower in the landiolol group. CONCLUSION: continuous administration of landiolol at a low dose after off-pump coronary artery bypass reduced the incidence of atrial fibrillation.