Efficacy of intentional undersized thoracic endovascular repair for Stanford type B aortic dissection.

OBJECTIVE: Thoracic endovascular aneurysm repair (TEVAR) is widely used for the treatment of aortic dissection. Endograft oversizing is a risk factor for stent graft-induced new entry tears and retrograde type A aortic dissection. However, there is no clear consensus on the optimal graft size selection for Stanford type B acute or subacute aortic dissection (TBAD). Herein, we examined the safety and efficacy of TEVAR using an intentionally undersized endograft to treat TBAD. METHODS: This retrospective chart review study included 82 patients who underwent TEVAR for acute or subacute Stanford TBAD between 2015 and 2022. We measured the true lumen diameter just distal to the subclavian artery and opted for a stent graft of the same diameter. In instances where deformation resulting from false lumen pressure displacement was pronounced, we measured the diameter at the site just proximal to the subclavian artery. Patients' characteristics, procedural, in-hospital, and follow-up data, and aortic remodeling were analyzed. The aortic diameter was analyzed using one-way analysis of variance followed by Dunnett's test. Survival and freedom from reintervention were estimated using Kaplan-Meier curves. RESULTS: The follow-up rate was 98.4%. The mean age was 58.3 ± 12.3 years, and 76 were men (92.7%). The mean diameters of the stent graft and native proximal landing zone were 30.9 ± 3.2 mm and 30.8 ± 3.0 mm, respectively. The oversize rate of the stent graft in relation to the native proximal aortic diameter was 0.3% ± 4.7%. In-hospital mortality was observed in one patient, retrograde type A aortic dissection in one patient, distal stent graft-induced new entry tear in zero patients, and type 1a endoleak in 22 patients (26.8%). Type 1a endoleaks, characterized by antegrade false lumen blood flow originating from the primary entry, in 12 patients spontaneously disappeared within 1 year of follow-up. According to aortic remodeling, 59 patients (86.8%) achieved complete aortic remodeling at the aortic arch level and 51 (75.0%) at the eighth thoracic vertebral level. The diameters of the aortic arch and descending aorta were significantly reduced compared with the postoperative measurements (P <.001). Survival rates were 97.5% and 93.6% at 1 and 3 years, respectively. Freedom from reintervention was 84.7% and 84.7% at 1 and 3 years, respectively. CONCLUSIONS: Intentionally undersized TEVAR was safe and achieved acceptable aortic remodeling despite a high rate of type 1a endoleaks. A type 1a endoleak was acceptable as it primarily diminished during the mid-term follow-up.

[Transient Left Ventricular Dysfunction after Giant Coronary Aneurysm Resection and Repair of Coronary Arteriovenous Fistula with Coronary Artery Bypass Grafting:Report of a Case].

Coronary artery aneurysm with coronary arteriovenous fistula is a relatively rare clinical setting. We report a surgical case of a 69-year-old male with a giant coronary artery aneurysm, finding coronary arteriovenous fistula on computed tomography (CT). We performed complete aneurysm excision and coronary artery bypass grafting with the left internal thoracic artery to the posterolateral branch. The fistula was located between the giant aneurysm on the circumflex artery and the coronary vein close to the coronary sinus, closed with aneurysm sac. The postoperative CT found no residual aneurysm and fistula. However, the great cardiac vein was thrombosed, and the impeded venous flow by the thrombus seemed to reduce the left ventricular ejection fraction (LVEF). Four months after the operation, the LVEF improved to the preoperative level.

Efficacy of Preoperative Bilateral Thoracic Paravertebral Block in Cardiac Surgery Requiring Full Heparinization: A Propensity-Matched Study.

OBJECTIVES: To assess the efficacy of preoperative bilateral paravertebral block (PVB) with general anesthesia (GA) in contributing to early extubation and decreasing opioid consumption in cardiac surgery. DESIGN: A propensity score-matched retrospective study. SETTING: A single tertiary medical center between January 2018 and December 2020. PARTICIPANTS: Adult patients undergoing isolated first-time aortic valve replacement and coronary artery bypass grafting with full sternotomy. INTERVENTIONS: A cohort of 44 patients who received PVB with GA (PVB group) was matched with 44 patients who underwent similar surgery with GA only (GA only group). MEASUREMENTS AND MAIN RESULTS: The completion rate of extubation in the operating room was significantly greater in the PVB group (65.9%) than in the GA only group (43.2%; p = 0.032). The completion rate of extubation within eight hours after surgery also was significantly greater in the PVB group (86.4%) than in the GA only group (68.2%; p = 0.042). The median amount of intraoperative fentanyl administered was significantly less in the PVB group (4.8 µg/kg; interquartile range [IQR], 3.3-7.2) than in the GA only group (8.4 µg/kg; IQR, 5.4-12.7; p < 0.001). The median amount of postoperative fentanyl administered was significantly less in the PVB group (6.8 µg/kg; IQR, 3.9-10.6) than in the GA only group (8.1 µg/kg; IQR, 6.2-15.9; p = 0.012). CONCLUSIONS: This study demonstrated that preoperative bilateral PVB combined with GA contributed to early extubation in isolated first-time aortic valve replacement and coronary artery bypass grafting and in the reduction of intraoperative and postoperative fentanyl consumption.

Effect of malnutrition and frailty status on surgical aortic valve replacement.

OBJECTIVES: To date, assessment of nutritional and frailty status in patients undergoing surgical aortic valve replacement remains unclear. This study aimed to assess the effect of geriatric nutritional risk index (GNRI) and Rockwood clinical frailty scale (CFS) on short-term and mid-term survival in patients who underwent surgical aortic valve replacement for aortic stenosis. METHODS: In total, 219 patients who underwent aortic valve replacement for aortic stenosis between Jan 1 2011 and Dec 31 2018 were retrospectively monitored in a single center. Mid-term survival was assessed using Kaplan-Meier analysis. Logistic and Cox regression analyses were performed to detect independent predictors for early and mid-term mortality. Follow-up was 97.7% complete, and a GNRI score ≤ 98 denoted malnutrition. RESULTS: In the univariable analysis, GNRI [odds ratio (OR) 0.91, 95% confidence interval (CI), 0.86-0.96, p < 0.001] and CFS (OR 2.00 95% CI 1.38-2.94, p < 0.001) were identified as significant risk factors for in-hospital mortality. Mid-term survival was significantly decreased in patients with malnutrition (3 and 5 year survival rates 83.9 and 76.9%, respectively, p < 0.001). Mid-term freedom from major cardiac and cerebrovascular events was significantly decreased in patients with malnutrition (p = 0.039). The CFS (hazard ratio 1.78) and GNRI (hazard ratio 0.95) were independent risk factors for mid-term survival in the univariable and multivariable analyses, respectively. CONCLUSIONS: A lower GNRI is associated with poor mid-term mortality and major cardiac and cerebrovascular events after surgical aortic valve replacement. A lower CFS score is associated with unfavorable mid-term outcomes.

Successful ligation of posterior tibial vein aneurysm performed according to intraoperative venography results.

A 23-year-old woman was diagnosed with a posterior tibial vein aneurysm that had resulted in deep vein thrombosis and a pulmonary embolism. The patient responded well to anticoagulation therapy, and surgical resection was planned to prevent recurrence. She was scheduled to undergo tangential aneurysmectomy and lateral venorrhaphy. However, the aneurysm could not be completely exposed because of adhesions. Therefore, venography was performed to identify the inflow and outflow vessels, which were ligated because an accessory venous communication was identified. Intraoperative venography can aid in the selection of simple ligation or reconstruction of a venous communication for the treatment of posterior tibial vein aneurysms.

New hemostatic technique with combined use of Hydrofit® and Surgicel®: an in vitro and in vivo study.

We developed an effective hemostatic technique using Hydrofit® and Surgicel® simultaneously. The aim of this study was to demonstrate the hemostatic efficacy of the Hydrofit® and Surgicel® combination technique through an in vitro experiment and to elucidate mid-term consequences of the combined components through an in vivo experiment. For the in vitro experiment, a closed circuit using a heparin-coated cardiopulmonary bypass circuit and a prosthetic graft was created. The amount of bleeding from the prosthetic graft was measured, and the following three hemostatic methods were applied: only gauze compression in control group, Hydrofit® application in Hydrofit group, Surgicel® spread Hydrofit® application in Hydrofit and Surgicel (HS) group, respectively. In the in vivo experiment, Hydrofit® and/or Surgicel® were implanted under skin on the back of rats (n = 10) at 4 points. In the control group, only an incision was made; in the Hydrofit, Surgicel, and HS groups, Hydrofit® and/or Surgicel® was implanted. One and three months later, each of the five rats were killed and in each section histopathologic examination was carried out. In the in vitro experiment, the amount of bleeding was 7.84 ± 1.08, 2.26 ± 1.02, and 0.87 ± 0.38 ml in the control, Hydrofit, and HS groups, respectively. The amount of bleeding in the HS group was more suppressed than in the Hydrofit group (p = 0.012). In the in vivo experiment, the maximal depth diameter of each remaining hemostatic sealant was measured. After 3 months, the diameter was 0, 2289.0 ± 768.2, 3850.3 ± 935.8 µm in Surgicel, Hydrofit and HS groups, respectively. The diameter was significantly increased in the HS group compared with the Surgicel and Hydrofit groups (p < 0.001, respectively,). In conclusion, the combination of Hydrofit® and Surgicel® was effective in achieving hemostasis. The remnants of Hydrofit® and Surgicel® were present for a long time in the tissues which could compress the surrounding tissue.

Intimal sarcoma of the pulmonary artery without 18F-fluorodeoxyglucose uptake.

Primary pulmonary intimal sarcoma is rare. Differentiating it from pulmonary thromboembolism is difficult because of similarities in clinical symptoms and imaging findings. Positron-emission tomography-computed tomography has been useful for diagnosing primary pulmonary intimal sarcoma. We describe a rare case of primary pulmonary intimal sarcoma that showed no abnormal 18F-fluorodeoxyglucose uptake on positron-emission tomography. We resected the mass and performed right ventricular outflow tract reconstruction. Proper diagnosis is necessary to determine appropriate therapy, Clinicians must consider the possibility of primary pulmonary intimal sarcoma even if imaging findings are inconsistent with the disease.

Maximization of the sealing effect of fibrin glue in aortic surgery.

OBJECTIVES: Fibrin glue is used to reinforce anastomosis in aortic surgery. There has not yet been a consensus on how it should be applied optimally. This study aimed to define the optimal condition of applying fibrin glue. METHODS: In experiment 1, we determined the optimal condition for spraying fibrin glue using an expanded polytetrafluoroethylene graft within a needle hole. The length and area of the fibrin cap within the hole were measured. In experiment 2, methods for applying fibrinogen were assessed by comparing brushing and spraying. In experiment 3, swine aorta segments sutured with a Dacron graft were divided into the following three groups: nothing was applied; fibrinogen was sprayed and rubbed using brush. The aorta was clamped and blood was infused from an occlusion catheter inserted into the graft. The pressure at the first appearance of blood leak was recorded. RESULTS: In experiment 1, among the four groups divided by the pressure and distance of spraying, the fibrin cap area in the group with 0.075 MPa and 2-cm spray distance was significantly larger than that in the group with 0.15 MPa and 2 cm (P < 0.01). In experiment 2, the fibrin cap area in the brushing group was significantly larger than that in the spraying group (P < 0.05). In experiment 3, the capacity to resist endoluminal pressure was higher in the brushing and combined spraying group compared with that in the sequential combined spraying group (P < 0.01). CONCLUSIONS: The brush and spray methods showed excellent hemostatic outcomes.

Compression of the Left Atrium and Left Ventricle by a Thoracoabdominal Aortic Aneurysm: A Case Report.

We describe the case of a 66-year-old man with a thoracoabdominal aortic aneurysm, who presented with cardiac failure; he had complained of shortness of breath. A contrast-enhanced computed tomography scan and transthoracic echocardiography showed compression of the left atrium and ventricle by a giant thoracoabdominal aortic aneurysm. The cardiac failure resolved after early prosthetic graft replacement surgery.

Nanobubble technology to treat spinal cord ischemic injury.

Background: Spinal cord ischemic injury is a severe complication of aortic surgery. We hypothesized that cerebrospinal fluid (CSF) oxygenation with nanobubbles after reperfusion could ameliorate spinal cord ischemic injury. Methods: Twenty white Japanese rabbits were categorized into 4 groups of 5 rabbits each: sham group, with balloon catheter insertion into the aorta; ischemia group, with spinal cord ischemic injury by abdominal aortic occlusion; nonoxygenated group, with nonoxygenated artificial CSF irrigation after spinal cord ischemic injury; and oxygenated group, with oxygenated artificial CSF irrigation after spinal cord ischemic injury. At 48 hours after spinal cord ischemic injury, the modified Tarlov score to reflect hind limb movement was evaluated. The spinal cord was histopathologically examined by counting anterior horn cells, and microarray and quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analyses were performed. Results: The oxygenated group showed improved neurologic function compared with the ischemia and nonoxygenated groups (P < .01 and P = .019, respectively). Anterior horn neuron prevention in the sham, nonoxygenated, and oxygenated groups was confirmed (mean modified Tarlov score: sham, 9.2 ± 1.9; nonoxygenated, 10.2 ± 2.2; oxygenated, 10.4 ± 2.2; ischemia, 2.7 ± 2.7). Microarray analysis identified 644 genes with twofold or greater increased signals between the ischemia and sham groups. Thirty-three genes related to inflammatory response were enriched among genes differentially expressed between the oxygenated and ischemia groups. Interleukin (IL)-6 and tumor necrosis factor (TNF) expression levels were significantly lower in the oxygenated group compared with the ischemia group, while qRT-PCR showed lower IL-6 and TNF expression levels in the oxygenated group compared with the ischemia group (P < .05). Conclusions: CSF oxygenation with nanobubbles after reperfusion can ameliorate spinal cord ischemic injury and suppress inflammatory responses in the spinal cord.

[Splenic Injury during Replacement of the Thoracoabdominal Aorta].

Extraperitoneal approach is commonly employed for thoracoabdominal aortic repair via Stoney incision. It is supposedly rare to encounter abdominal visceral bleeding during that procedure. However, the spleen may spontaneously adhere to the adjacent peritoneum, which could induce incidental injury to the spleen by its anterior mobilization during extraperitoneal approach. Unless we bare its potential risk in mind, bleeding from the spleen may be overlooked, which results in hemodynamic deterioration. We have experienced 3 cases of splenic injury that necessitated hemostatic maneuvers for bleeding during and just after the thoracoabdominal aortic repair.

Morphometrical and biomechanical analyses of a stentless bioprosthetic valve: an implication to avoid potential primary tissue failure.

OBJECTIVES: Stentless bioprosthetic valves provide hemodynamic advantages over stented valves as well as excellent durability. However, some primary tissue failures in bioprostheses have been reported. This study was conducted to evaluate the morphometrical and biomechanical properties of the stentless Medtronic Freestyle™ aortic root bioprosthesis, to identify any arising problem areas, and to speculate on a potential solution. METHODS: The three-dimensional heterogeneity of the stentless bioprosthesis wall was investigated using computed tomography. The ascending aorta and the right, left, and non-coronary sinuses of Valsalva were resected and examined by an indentation test to evaluate their biomechanical properties. RESULTS: The non-coronary sinus of Valsalva was significantly thinner than the right sinus of Valsalva (p < 0.01). Young's modulus, calculated as an indicator of elasticity, was significantly greater at the non-coronary sinus of Valsalva (430.7 ± 374.2 kPa) than at either the left (190.6 ± 70.6 kPa, p < 0.01) or right sinuses of Valsalva (240.0 ± 56.5 kPa, p < 0.05). CONCLUSIONS: Based on the morphometrical and biomechanical analyses of the stentless bioprosthesis, we demonstrated that there are differences in wall thickness and elasticity between each sinus of Valsalva. These differences suggest that the non-coronary sinus of Valsalva is the most vulnerable and at greater risk of tissue failure. The exclusion of the non-coronary sinus of Valsalva may be beneficial to mitigate the long-term risks of tissue failure in the stentless bioprosthesis.

[Surgical Embolectomy for Acute Massive Pulmonary Thromboembolism Requiring Percutaneous Cardiopulmonary Support after Thoracoabdominal Aorta Replacement].

A 48-year-old man was admitted to our hospital and underwent thoracoabdominal aorta replacement. Eight days postoperatively, he developed severe dyspnea and transient drop in blood pressure suddenly following walk rehabilitation. Contrast-enhanced computed tomography showed thrombi in the bilateral main pulmonary artery. Respiratory failure and unstable hemodynamics developed, which required percutaneous cardiopulmonary support (PCPS). Because catheter embolectomy and thrombolytic therapy via pulmonary artery catheter were not effective, surgical thrombectomy was performed. PCPS was successfully removed on the following day. The patient was extubated on postoperative day 10 and discharged without complications on day 46 following rehabilitation. It is important to save a critically ill patient with acute pulmonary embolism requiring PCPS, and surgical treatment should be performed without delay in such patients.