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.

Prognostic value of brachial-ankle pulse wave velocity changes post-transcatheter aortic valve replacement.

Transcatheter aortic valve replacement (TAVR) offers a solution, especially for high-risk aortic stenosis (AS) patients. However, patient outcomes post-TAVR show variability, highlighting the need for reliable prognostic indicators. Brachial-ankle pulse wave velocity (baPWV), a measure of arterial stiffness, may predict outcomes post-TAVR. This study aims to explore baPWV's prognostic value in relation to all-cause mortality post-TAVR. This study prospectively enrolled 212 severe AS patients undergoing TAVR between September 2015 and December 2021, focusing on pre- and post-TAVR baPWV measurements to explore associations with all-cause mortality. Of the 212 patients (119 females, 93 males, mean age 85 years), post-TAVR baPWV increased significantly from 1589 ± 376 to 2010 ± 521 cm/s (p < 0.001). Aortic valve (AV) peak velocity and mean pressure gradient decreased, while AV area increased, indicating procedural success. Despite this, 88% of patients experienced an increase in baPWV, with higher pre-procedure AV peak velocity and mean pressure gradient identified as predictors of increased baPWV post-TAVR. Over 23 months, 29 patients (14%) reached the primary endpoint of all-cause mortality. Notably, changes in baPWV, rather than baseline values, were significantly associated with event-free survival (HR: 0.64 per 1SD increase, p = 0.009). The study highlights the prognostic value of baPWV changes post-TAVR in predicting patient outcomes. Elevated baPWV post-TAVR may reflect a beneficial adaptation to altered hemodynamics, suggesting the need for individualized patient evaluation and the integration of baPWV measurements into clinical practice for improved post-TAVR management.

[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.

[Dynamics Evaluation of Remodeling Operation Using 4-dimentional Computed Tomography].

OBJECTIVES: The extensibility of the aortic root after the remodeling procedure was evaluated using 4-dimentional computed tomography( 4D-CT). PATIENTS AND METHODS: Seventeen patients( 13 males/4 females), mean age 52 years, who had undergone the remodeling procedure in the last 3 years were included. To understand the dynamics of the aortic root after reconstruction, the R-R interval on the electrocardiogram was divided into 10 equal parts, and the percentage change in area of the basal ring/Valsalva sinus/sino-tubular junction (STJ) level was calculated to evaluate the extensibility of the aortic root. For the basal ring, changes in ellipticity and circumference were also compared. RESULTS: Basal ring, Valsalva sinus, and STJ area changes with cardiac cycle were similar to those in the control group. Basal ring showed a regular circle in systole and an oval in diastole, and its circumference was enlarged in systole. CONCLUSIONS: The use of 4D-CT made it possible to evaluate the extensibility of the aortic root after remodeling procedure. In particular, the mobility of the basal ring is large, suggesting that it guarantees the physiological opening and closing of the valve and contributes to its durability.

[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.

[Prevention and Treatment of Mediastinitis Following Cardiac Surgery].

Mediastinitis after cardiac surgery occurs about 1% of the time and is associated with adverse effects on both short- and long-term outcomes. Therefore, prevention of mediastinitis is very important. However, when this complication occurs, a radical cure should be performed using a safe and reliable method. Many pre-, intra-, and post-operative risk factors have been reported. Perioperative management based on an understanding of the pathological condition that causes this complication is an effective prevention strategy. Early detection and treatment are most important, and there should be close coordination with plastic surgeons. Recently, negative pressure wound therapy has been used widely and appears to be effective for this complication.

[Intraoperative Endoscopic Evaluation of the Aortic Valve in Aortic Valve Repair].

This report discusses intraoperative endoscopic evaluation of the aortic valve performed in 2 cases of aortic valve repair. The "direct" or real image by the endoscopy helped to confirm the preoperatively-known lesion and even to detect a new legion which was not detected preoperatively. The endoscopy also enabled the evaluation of the aortic valve under the pressure-loaded condition without releasing the aortic clamp. Postoperative aortic regurgitation was grade I or less in both cases, although it progressed to grade II at 1 year in case 2. Echocardiographic parameters demonstrated no change in the size of the aortic root configuration for 8 and 5 years in case 1 and case 2, respectively. Intraoperative aortic endoscopy was useful to define the pathogenesis of aortic regurgitation and to evaluate the cusp repair procedures, which may contribute to a good mid-term result of aortic valve repair.

Operative technique for tracheo-innominate artery fistula repair.

Tracheo-innominate artery fistula is fatal unless treated surgically. We describe our surgical approach and results in seven patients. The average patient age was 15.7 years; all patients had prior severe neurological deficits. Three of seven patients were in hemorrhagic shock; control of preoperative bleeding was achieved with tracheostomy tube cuff overinflation. The innominate artery and the trachea were exposed through a collar incision and partial upper sternotomy. The innominate artery was divided at the aortic arch and at the bifurcation, with one exception. Cerebral blood flow was monitored by the blood pressure difference in the bilateral upper extremities and by near-infrared spectroscopy. The tracheal fistula was left adherent to the innominate artery in all but one patient. All patients were discharged without new neurologic deficits or severe morbidity. Overall survival was 84% at 37 months, without any vascular, tracheal, or neurological events.

[Operation for aortic regurgitation after ascending aortic replacement].

In the clinical setting, surgery for aortic regurgitation after ascending aortic replacement is performed in a patient that underwent ascending aortic replacement due to acute aortic dissection (Stanford A). The 1st step is to determine preoperatively whether only surgery for aortic regurgitation should be performed or whether surgery should be performed for both aortic regurgitation and residual aortic dilatation. This decision should be based on the patient's general condition. Also, the possibility of preservation of the native aortic valve should be considered. Staged re-sternotomy using an inferior T-shaped mini-sternotomy is useful for a retrosternal giant aneurysm of the thoracic aorta in combined surgery on both the aortic valve and aortic aneurysm. Steady cardiac and cerebral protection is important for obtaining good results. Postoperative intensive critical care and careful follow-up in the outpatient clinic are also important. In conclusion, it is important for surgeons to become proficient in surgery for aortic valve regurgitation after ascending aortic replacement, because more of these patients will be encountered in the future.

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.

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.

[Total arch replacement using a new sheathless open stent-grafting technique].

Total arch replacement for extended distal arch aneurysm has been known to have a poor outcome because of a limited view on the distal side. An open stent-grafting technique has been employed in many institutions, but several complications have been reported. Specifically, embolism of the distal artery from aneurysm debris and injury to the aortic wall are serious complications. Therefore, we have developed and tested a new sheathless stent-grafting system. We use a small-sized sheath (12 Fr) as an inner cylinder and a stainless-steel Z-shaped stent (Gianturco:William Cook Europe A/S) in the distal part of the graft. This system is deployed by releasing 3-0 polypropylene suture after inserting the full-length graft. The major advantages of this system, compared with other devices, include flexibility, less invasiveness to the aortic wall and low potential for graft migration. This new system may be feasible and clinically effective in the surgical treatment of extended distal arch aneurysm.

[Long-term outcome of repair of prolapsing anterior mitral leaflet with artificial chordae replacement].

OBJECTIVE: We have performed a simple and uniform technique for reconstruction of artificial chordae in patients with anterior mitral prolapse since 1994. In this study, we investigated the long-term clinical and echocardiographic results of chordae replacement with Gore-Tex sutures for anterior mitral leaflet prolapse. METHODS: A pair of Gore-Tex sutures is passed through a small autologous pericardium and tied on one side of the pericardium. Double-armed mattress stitches on the side without a knot are passed through the head of the papillary muscle and another small pericardium and then tied down. Using this simple technique, 2 pairs of artificial chordae are made. The length of the artificial chordae is determined during the leak test. Chordal replacement with this technique was performed in 30 patients (mean age, 59.3 years) with anterior mitral leaflet prolapse. Echocardiography was performed annually in these patients. Follow-up ranged from 0.2~16.2( 8.0±5.1) years. RESULTS: There were no hospital deaths. Twenty-one patients had no mitral regurgitation( MR) and the others had trivial or mild MR. There were 2 reoperations and 4 cases with recurrent moderate MR in this series. Kaplan-Meier survival and freedom from reoperation at 15 years were 84% and 93%,respectively. Overall, freedom from recurrent moderate or severe MR at 15 years was 81%. CONCLUSIONS: Our simple chordae replacement technique with Gore-Tex sutures for anterior mitral prolapse, results in good long-term durability. To avoid recurrence of regurgitation, intraoperative complete repair is essential.

[Primary cardiac leiomyosarcoma originating from the left atrium].

Primary malignant cardiac tumors occur extremely rarely. Among these, leiomyosarcomas are exceptionally rare. We described a case of left atrial leiomyosarcoma in which surgical intervention was followed by adjuvant radiation therapy. A 74-year-old male was admitted for dyspnea. Chest X-ray showed severe pulmonary congestion. Echocardiography revealed large tumor in the left atrium. Emergency operation was performed. The tumor invaded the left atrial wall and the mitral valve, and the lesion was resected as extensively as possible. Postoperative pathologic examination confirmed leiomyosarcoma. He underwent adjuvant radiotherapy postoperatively. However, early local recurrence was recognized. He died due to sudden circulatory collapse in 8th postoperative month. As cardiac leiomyosarcomas have extremely poor prognosis, complete resection and effective postoperative adjuvant therapy are necessary.

Novel technique in frozen elephant trunk positioning method using the ostium of the coronary artery on transesophageal echocardiography as an index.

The frozen elephant trunk (FET) technique is useful in the single-stage treatment of aortic arch aneurysms. Since there is no established implantation method for evaluating the distal end of the FET during surgery, we propose the FET positioning method using the ostium of the coronary artery on transesophageal echocardiography (TEE) as an index. We performed 11 total arch replacement operations using an FET for aortic arch aneurysm. The planned position of the FET was determined by computed tomography (CT), and the distance to the ostium of the coronary artery was measured. Intraoperatively, using TEE as a guide, the FET was implanted using our method. Postoperative CT was evaluated the distance from the planned FET position, and the average and median difference was only 0.96 cm and 0.6 cm, respectively. TEE-guided FET deployment using the coronary artery ostium as an index is a simple and reproducible technique.

Extracorporeal membrane oxygenation for the control of pulmonary artery hemorrhage.

We report a case of catheter-induced pulmonary hemorrhage, which had a favorable outcome on using extracorporeal membrane oxygenation. This procedure helped shunt pulmonary blood flow and significantly reduced bleeding from the pulmonary artery. Massive hemoptysis was observed while weaning the patient off cardiopulmonary bypass. Thus, catheter-induced pulmonary hemorrhage was suspected. After the bronchial blocker was inserted, extracorporeal membrane oxygenation was initiated to reduce pulmonary blood flow. The bronchial blocker was removed the day after the surgery, and the extracorporeal membrane oxygenation was withdrawn on the fourth day after the surgery. Tracheal bleeding did not recur during the postoperative period.

Comparison of intra-wound drainage tubes after cardiac surgery: Blake drains versus Multichannel drains.

BACKGROUND: Blake and Multichannel drains have been used in our department. Although both are made up of silicone, they differ in structure. We investigated the drainage effects of these two types of drains and the factors related to their occlusion. METHODS: We enrolled 100 consecutive cases (50 using Blake drains and 50 using Multichannel drains) of cardiovascular surgery performed in our department from July 2017 to April 2018. The formation of thrombi in the groove and tube of the drains was evaluated in each case. The tube portion was checked for the presence of occlusion, and the groove portion was examined for the number and ratio of thrombi formed in the grooves. RESULTS: The clot formation rate in the groove part was slightly higher in the Multichannel cases than in the Blake cases. In addition, analysis within the Multichannel cases revealed that the thrombus formation rate between the catheter lumen and the three grooves (without the catheter lumen) was significantly different, with the highest groove clot formation rate occurring in the catheter lumen. Out of 34 cases of occlusions, there were 26 cases (52%) of Multichannel drains, and only 8 cases (16%) of Blake drains (p < 0.01). A multiple logistic regression analysis revealed that the most important contributory factor in tube obstruction was the drain type. CONCLUSIONS: The catheter lumen of the Multichannel drain was more susceptible to thrombus formation than the groove. The tube part of the Multichannel drain was more prone to occlusion than that of the Blake drain.

Atrial pacing and administration of nifekalant hydrochloride for unstable atrial fibrillation: a case report.

BACKGROUND: Atrial fibrillation (AF) is a common arrhythmia in patients with hypertrophic cardiomyopathy (HCM) and can deteriorate haemodynamic status. CASE SUMMARY: We report a case of a 77-year-old woman with cardiogenic shock due to paroxysmal AF, complicated with HCM and aortic stenosis. Atrial fibrillation was successfully managed with temporary atrial pacing and administration of nifekalant hydrochloride without invasive mechanical circulatory support until surgery. Septal myectomy, aortic valve replacement, and pulmonary vein isolation were performed. DISCUSSION: This case suggests that atrial pacing and nifekalant may be safe and effective for rhythm control.

Anomalous origin of the coronary artery coursing between the great vessels presenting with a cardiovascular event (J-CONOMALY Registry).

AIMS: Anomalous origin of the coronary artery (AOCA) with an inter-arterial course (IAC) between the great vessels poses a risk for a life-threatening cardiovascular event. We assessed, in a registry-based study, the clinical features, treatment strategies, and prognoses of life-threatening cardiovascular events ensuant to AOCA. METHODS AND RESULTS: Included were 65 AOCA patients (48 men/17 women, aged 41 ± 23 years) from 40 clinical centres who had experienced sudden cardiac arrest (SCA) (n = 30), acute myocardial infarction (AMI) (n = 5), angina (n = 23), or syncope (n = 7). The anomalous vessel was the right coronary artery in 72% of patients and left coronary artery in 28%; the ostium was slit-like in 42%. Coronary luminal narrowing ≥75% was absent in patients with SCA or syncope (86% and 57%, respectively), but occlusion or narrowing was seen in those with AMI (100%) or angina (52%). Age ≤40 years, male sex, sporting activity, absence of prodromal symptoms, acutely angled (≤30°) take-off from the aorta, and absence of luminal narrowing of the IAC segment were associated with SCA in this patient group. Coronary vasospasm was inducible in 12 of 17 patients without coronary narrowing. Management included surgical revascularization (n = 26) percutaneous coronary intervention (n = 9), and medical treatment (n = 26). Four SCA patients died while hospitalized; no others died during the median 5.0 (range, 1.8-7.0)-year follow-up period. CONCLUSIONS: In patients with AOCA, age ≤40 years, male sex, sporting activity, and an acute take-off angle appear to be risk factors for SCA. Appropriate management can be beneficial. Confirmation in a large-scale study is warranted.