[Rupture of Artificial Blood Vessel by a Sternal Wire:Report of a Case].

Formation of a pseudoaneurysm due to blood leakage from the anastomotic site of the vascular graft in large-diameter vessels is often seen, but formation of a pseudoaneurysm from the non-anastomotic site is extremely rare. A 68-year-old woman presented with a history of double valve replacement for combined valvular disease at 37 years old and hemiarch replacement for thoracic aortic dilatation at 65 years old. She visited the emergency room with a 2-week history of chest pain. Contrast-enhanced computed tomography (CT) revealed a 5-cm-diameter pseudoaneurysm and extravasation from the ascending aorta, so emergency surgery was performed. Around the ascending aorta area, we confirmed bleeding from a 5-mm dehiscence in the non-anastomotic part of the graft prosthesis, so hemostasis was performed with a cross-stitch mattress suture over a felt strip. Initially, the cause of the pseudoaneurysm was unknown, but re-examination of CT images from after the previous hemiarch replacement confirmed contact between the sternal wire and graft prosthesis. The wire was thus considered to have caused damage and bleeding. The patient was discharged from the hospital with a good postoperative course and is being followed-up in the outpatient department.

Usefulness of Motor Evoked Potential Measurement and Analysis of Risk Factors for Spinal Cord Ischaemia from 300 Cases of Thoracic Endovascular Aortic Repair.

OBJECTIVE: This study investigated the usefulness of motor evoked potentials (MEPs) for intra-operative monitoring to detect the risk of spinal cord ischaemia (SCI) during thoracic endovascular aortic repair (TEVAR). Risk factors for SCI in TEVAR were also analysed. METHODS: Among 330 TEVARs performed from February 2009 to October 2018, 300 patients underwent intra-operative MEP monitoring. SCI risk groups were extracted based on MEP amplitude changes using a cutoff value of 50%. When the amplitude decreased to < 50% of the pre-operative value, intra-operative mean arterial pressure (MAP) was increased by about 20 mmHg using noradrenaline, whereas MAP was usually controlled to about 80 mmHg during surgery. Other efforts were also made to increase MEP amplitude by increasing cardiac output, correcting anaemia, and finishing the surgery promptly. Based on MEP amplitude data, SCI risk groups were extracted and risk factors for SCI in TEVAR were analysed. RESULTS: A total of 283 non-SCI risk patients and 17 SCI risk patients by MEP monitoring were extracted; only 1.0% developed immediate paraplegia and none developed delayed paraplegia. Bivariable analysis showed significant differences in chronic kidney disease, haemodialysis, artery of Adamkiewicz closure, and stent graft (SG) covered length ≥ 8 vertebral bodies. Logistic regression analysis showed hyperlipidaemia (odds ratio [OR] 3.55, 95% confidence interval [CI] 1.08 - 11.67; p = .037), SG covered length ≥ 8 vertebral bodies (OR 1.35, 95% CI 1.02 - 1.78; p = .034), and haemodialysis (OR 27.78, 95% CI 6.02 - 128.22; p < .001) were the most influential risk factors for SCI in TEVAR. CONCLUSION: MEPs might be a useful monitoring tool to predict SCI in TEVAR. In addition, hyperlipidaemia, SG covered length ≥ 8 vertebral bodies, and haemodialysis represent key risk factors for SCI during TEVAR.

[Pulmonary Artery Transection in Surgery for Coronary Artery Fistula].

Coronary artery fistula is a rare abnormality in the communication between a coronary artery and any of the cardiac chambers or major vessels. At present, there is no standard surgical treatment and the most appropriate method is selected on a case-by-case basis. We report one case of coronary artery fistulae in which pulmonary artery transection was required around the left main trunk (LMT). A 62-year-old man who had coronary artery fistulae with an aneurysm which increased from 12 mm to 16 mm in a two-year span. The fistula was located adjacent to the LMT. A complete aneurysm excision under cardiopulmonary bypass was performed, which required pulmonary artery transection. No postoperative complications occurred. Postoperative coronary computed tomography scan showed intact coronary arteries and complete aneurysm removal.

Simultaneous upper and lower body perfusion using hypothermia during thoracoabdominal aortic surgery.

BACKGROUND: In open thoracoabdominal aortic aneurysm (TAAA) repair, we have been performing vascular reconstruction under moderate to deep hypothermia and assisted circulation using simultaneous upper and lower body perfusion. This method is effective for protecting the spinal cord and the brain, heart, and abdominal organs and for avoiding lung damage. METHODS: TAAA repair was performed under hypothermia at 20-28 °C in 18 cases (Crawford type I in 0 cases, type II in 5, type III in 3, type IV in 4, and Safi V in 6) between October 2014 and January 2023. Cardiopulmonary bypass was conducted by combined upper and lower body perfusion, with perfusion both via the femoral artery and either transapically or via the descending aorta or the left brachial artery. RESULTS: The ischemic time for the artery of Adamkiewicz and the main segmental arteries was 40-124 min (75 ± 33 min). No spinal cord ischemic injury or brain or heart complications occurred. One patient with postoperative right renal artery occlusion and one with an infected aneurysm required tracheostomy, but the intubation time for the other 16 was 32 ± 33 h. The duration of postoperative intensive care unit stay was 6.5 ± 6.2 days, the length of hospital stay was 29 ± 15 days, and no in-hospital deaths occurred. CONCLUSIONS: Simultaneous upper and lower body perfusion under moderate to deep hypothermia during thoracoabdominal aortic surgery may avoid not only spinal cord injury, but also cardiac and brain complications.

Mechanism of Increased Spinal Cord Blood Flow due to Noradrenaline Administration Using Vascular Resistance: An Experimental Study Using a Canine Model.

Background: During thoracoabdominal aortic surgery, the spinal cord is placed under ischemic conditions. Elevation of systemic blood pressure is thus recommended as a method of increasing the blood supply from collateral networks. This study examined the mechanisms by which noradrenaline administration increases spinal cord blood flow (SCBF) by elevating systemic blood pressure. Methods: In beagles (n = 7), the thoracoabdominal aorta and L2-L7 spinal cord segmental arteries (SAs) were exposed and a distal perfusion bypass was created to simulate clinical practice. SCBF was measured by laser flowmetry at the L5 dura mater and spinal cord perfusion pressure (SCPP) was measured inside the clamped aorta. The six pairs of SAs from L2 to L7 were clamped, and mean systemic blood pressure (mSBP), SCBF, and SCPP were measured before and after clamping and after starting continuous infusion of noradrenaline at 0.5 µg/kg/min. Rates of change in systemic vascular resistance (SVR) and spinal cord vascular resistance (SCVR) were calculated from the measured values. Results: With no SA clamping (control), the rate of increase in SCVR was 0.74 times the rate of increase in SVR (y = 0.2 + 0.74x, r = 0.889, r2 = 0.789; P < 0.01). When all six pairs of SAs were clamped, a weak correlation was evident between rate of change in SCVR and rate of change in SVR, and the rate of increase in SCVR was lower than the rate of increase in SVR (y = 0.39 + 0.07x, r = 0.209, r2 = 0.039; P < 0.01). When all six pairs of SAs were clamped in the absence of distal perfusion, a weak correlation was also evident between rate of change in SCVR and rate of change in SVR, and the rate of increase in SCVR was lower than the rate of increase in SVR (y = 0.19 + 0.08x, r = 0.379, r2 = 0.144; P < 0.01). Conclusions: The rate of increase in SCVR induced by noradrenaline administration was lower than the rate of increase in SVR in the control group with no spinal cord SA clamping and in both experimental groups with clamped SAs (with and without distal perfusion), creating an environment conducive to spinal cord flow distribution.

Open Repair for Patent Ductus Arteriosus Aneurysm in an Adult.

Ductus arteriosus aneurysm (DAA) is rarely encountered in adults. There have been several hypotheses regarding its origin and potential indications for intervention in asymptomatic cases. If left untreated, rupture, compression of surrounding organs, and serious complications due to thromboembolism may occur, and aggressive surgical intervention appears desirable for patients who can tolerate surgery. We report a case involving a 30-mm, saccular, patent DAA that was incidentally discovered in a 49-year-old man on computed tomography. Open repair was performed by femorofemoral bypass assistance, which allowed decompression of the aorta and aneurysm and successful closure of the aortic and pulmonary artery ends.

Transapical aortic perfusion using a deep hypothermic procedure during descending thoracic or thoracoabdominal aortic surgery.

BACKGROUND: In descending thoracic aortic aneurysm (DTAA) or thoracoabdominal aortic aneurysm (TAAA) surgery, though proximal anastomosis using deep hypothermic circulatory arrest (DHCA) is often selected, there are issues surrounding brain and heart protection. In this study, the usefulness of concomitant upper body perfusion via transapical aortic cannulation during deep hypothermic surgery was examined. METHODS: Between October 2014 and May 2019, 5 patients (Crawford extent II chronic dissection, N.=3; extent IV aneurysms, N.=1; DTAA, N.=1) underwent DTAA/TAAA repair under deep hypothermia using transapical aortic perfusion. A proximal anastomosis and artery of Adamkiewicz (AKA) reconstruction were performed under continuous perfusion of the upper and lower body at 20 °C. RESULTS: The time from aortic cross-clamping to proximal anastomosis was 69±33 minutes, and it took 86±47 minutes to AKA reperfusion. There was no spinal cord ischemic injury or brain or heart complications. One patient required tracheostomy, and the average postoperative intubation time for the other patients was 57±52 hours. All patients were discharged, and the average postoperative hospital stay was 25.6±8.1 days. CONCLUSIONS: Concomitant upper body perfusion by the transapical aortic approach contributes to avoidance of brain and heart complications and maintaining spinal cord circulation under deep hypothermic DTAA/TAAA surgery.

Direct Monitoring of Reconstructed Segmental Arterial Pressure during Deep Hypothermic Thoracoabdominal Aortic Aneurysm Surgery.

Deep hypothermia in thoracoabdominal aortic aneurysm operations is considered extremely useful for ensuring sufficient time to reconstruct the segmental arteries feeding the spinal cord. However, because the amplitude of motor evoked potentials (MEPs) decrease or disappear during deep hypothermia, feasible methods for assessing spinal cord circulation have not yet been reported. Performing additional segmental arterial reconstructions that rely on MEPs is also impractical. In the present case, to ascertain spinal cord circulation under deep hypothermia, we intraoperatively measured the reconstructed segmental arterial pressure in real time and investigated whether sufficient spinal cord blood flow had been attained.

Direct reopening of the occluded hepatic veins of Budd-Chiari syndrome: verification of our operative method by the perioperative course of esophageal varices.

OBJECTIVE: A total of 69 patients with Budd-Chiari syndrome (BCS) were operated by direct approach under cardiopulmonary bypass (CPB). To assess the operative procedure, the perioperative course of esophageal varices (EVs) was evaluated. PATIENTS AND METHODS: Of the 69 patients, 59 (22 females) were enrolled in this study because they had complete follow-up data for endoscopic evaluation of EVs. Their mean age was 46.3 ± 13.0 years (range 21-73.3 years). EVs were found in 52 patients. Under partial cardiopulmonary bypass, the inferior vena cava (IVC) was incised. The obstruction of the IVC was excised, and the occluded hepatic veins were reopened. The incised IVC was reconstructed with an auto-pericardial patch. RESULTS: Postoperatively, the repaired IVC was patent in all patients. The average number of patent hepatic veins (HVs) increased from 1.23 ± 0.81 to 2.21 ± 0.97/patient. The pressure gradient between the IVC and right atrium (RA) decreased from 12.4 ± 5.52 to 4.46 ± 3.21 mmHg. The indocyanine green clearance test (ICG) at 15 min decreased from 31.57 ± 17.44 to 22.27 ± 15.23%. EVs had disappeared in 13 patients at discharge and in 6 patients at late postoperative follow-up. CONCLUSION: Our operative procedure for BCS is useful for decreasing portal pressure, which is reflected by disappearance of EVs. Therefore, the high risk of EV rupture could be avoided by reopening the occluded HVs.

Transapical aortic perfusion using a deep hypothermic procedure to prevent dissecting lung injury during re-do thoracoabdominal aortic aneurysm surgery.

BACKGROUND: Avoiding various complications is a challenge during re-do thoracoabdominal aneurysm surgery. CASE PRESENTATION: A 56-year-old man had undergone surgery for type I aortic dissection four times. The residual thoracoabdominal aortic aneurysm that had severe adhesions to lung parenchyma was resected. Since the proximal anastomotic site was buried in lung parenchyma, deep hypothermia was essential to avoid lung dissection and to protect the spinal cord during the proximal anastomosis. The deep hypothermia was induced with bilateral infusion of cardiopulmonary bypass by femoral artery cannulation for the lower body and by transapical cannulation for the upper body because of easy access. There was no hemorrhagic tendency after deep hypothermic bypass. The patient was discharged uneventfully. CONCLUSIONS: For upper body perfusion, transapical aortic cannulation was a simple and effective procedure during left thoracotomy.