Morphologic prognostic factor for thoracoabdominal aortic dilation after acute type A dissection repair.

OBJECTIVES: Risk factors for late-term aortic dilation after acute type A aortic dissection repair have not been well examined. The goal of this study was to determine the relationship between the abdominal aortic true lumen location and thoraco-abdominal aortic dilation after surgical repair for acute type A aortic dissection. METHODS: Patients who were preoperatively diagnosed with acute type A aortic dissection between April 2014 and July 2022 were included in this study. We evaluated the renal artery-level dissected aortic morphology and classified the study population into 2 groups: the ventral (those with the true lumen located on the ventral side) and the dorsal (other patients not assigned to the ventral group) groups, based on the location of the true lumen. Aortic dilation was defined as thoraco-abdominal aortic expansion ≥5 mm on 1-year postoperative computed tomography images. RESULTS: We examined 49 surgical patients who were assigned to the ventral (n = 22) and dorsal (n = 27) groups. The number of patients with ≥5 mm thoraco-abdominal aortic dilation after the operation was significantly higher in the ventral group than in the dorsal group (90.9% vs 51.9%, P = 0.009). The multivariable logistic regression analysis showed that the ventral type was an independent prognostic factor for thoraco-abdominal aortic dilation after the operation (odds ratio, 6.01; 95% confidence interval, 1.56-23.77; P = 0.009). CONCLUSIONS: The location of the true lumen of the abdominal aorta in acute type A aortic dissection may be a prognostic factor for thoraco-abdominal aortic dilation after surgical repair.

Fenestrated and covered frozen elephant trunk technique for management of chronic aortic dissection.

BACKGROUND: Reintervention for residual dissection after repaired type A aortic dissection remains challenging. When a frozen elephant trunk (FET) is used, the incidence of distal stent graft-induced new entry (d-SINE) is reportedly high in chronic dissection. AIMS: We report a case of successful redo arch repair using fenestrated and covered FET techniques for chronic residual aortic dissection. METHODS: After the arch was transected proximal to the left subclavian artery (LSCA), and a modified FET prosthesis, in which the distal edge of the FET was covered, was deployed. A fenestration was created in the FET on the LSCA aspect. RESULTS: The postoperative course was uneventful. DISCUSSION: The distal edge of the FET was covered to prevent d-SINE. Creation of a fenestration on the FET eliminates the need to reconstruct the LSCA. CONCLUSION: The fenestrated FET technique simplifies redo arch repair and the covered FET technique can potentially prevent d-SINE.

Effects of a frozen elephant trunk on postoperative renal dysfunction in acute type A aortic dissection extending into the renal artery.

BACKGROUND: We investigated the effects of frozen elephant trunk (FET) implantation on clinical outcomes in patients with acute type A aortic dissection (ATAAD) extending into the renal artery (RA). METHODS: Between May 2016 and April 2021, 136 patients underwent surgery for ATAAD at our hospital. Patients who died within 7 days postoperatively and those without preoperative contrast-enhanced computed tomography (CT) data were excluded from the study. The remaining 125 patients were included in this study. A preoperative CT-documented RA abnormality was found in 53 patients. Clinical outcomes, including renal dysfunction and CT findings, were compared between 29 patients with and 24 patients without the FET prosthesis. RESULTS: Among the 53 patients with RA abnormalities, origin of the RA from the false lumen was the most common type of abnormality. The percentage of men and rate of arch repair were higher, and the operation, cardiopulmonary bypass, and lower body hypothermic circulatory arrest times were longer in the FET than in the non-FET group. Early mortality rates were similar between groups. The incidence of postoperative acute kidney injury (AKI) was lower in the FET group (35% vs. 67%, p = 0.028). Multivariable analysis showed that FET implantation was associated with a low incidence of AKI (odds ratio: 0.28, 95% confidence interval: 0.08-0.96; p = 0.043). Among the 125 patients with or without RA abnormalities, no predictor of AKI was identified. CONCLUSION: FET implantation protected against postoperative AKI in patients with ATAAD extension into the RA.

Bicuspidalization of the Native Tricuspid Aortic Valve: A Porcine in Vivo Model of Bicuspid Aortopathy.

Objective: To examine early histologic changes in the aorta exposed to bicuspid flow. Material and Methods: A porcine bicuspid aortopathy model was developed by suturing aortic cusps. Of nine pigs, eight underwent sham surgery (n=3) or bicuspidalization (n=5); one was used as an intact control. Wall shear stress (WSS) was assessed by computational fluid dynamics (CFD). Animals were exposed to normal or bicuspid flow for 48 h and were then euthanized for histologic examinations. Results: No animal died intraoperatively. One animal subjected to bicuspidalization died of respiratory failure during postoperative imaging studies. Echocardiography showed the aortic valve area decreased from 2.52±1.15 to 1.21±0.48 cm2 after bicuspidalization, CFD revealed increased maximum WSS (10.0±5.2 vs. 54.0±25.7 Pa; P=0.036) and percentage area of increased WSS (>5 Pa) in the ascending aorta (30.3%±24.1% vs. 81.3%±13.4%; P=0.015) after bicuspidalization. Hematoxylin-eosin staining and transmission electron microscopy showed subintimal edema and detached or degenerated endothelial cells following both sham surgery and bicuspidalization, regardless of WSS distribution. Conclusion: A bicuspid aortic valve appears to increase aortic WSS. The endothelial damage observed might have been related to non-pulsatile flow (cardiopulmonary bypass). Chronic experiments are needed to clarify the relationship between hemodynamic stress and development of bicuspid aortopathy.

Reconstruction of the left subclavian artery in arch repair: An end-to-side anastomosis technique.

BACKGROUND: The left subclavian artery (LSCA) is deeply located and difficult to visualize in some cases of total arch replacement. AIMS: We report an end-to-side anastomosis technique that enables safer and easier anatomical reconstruction of the LSCA. MATERIALS AND METHODS: Under Hypothermic circulatory arrest, the origin of the LSCA was ligated and pulled caudally. With clamping the distal LSCA, a graft was anastomosed to the anterior wall of the LSCA and antegrade cerebral perfusion to the LSCA was ensured through the anastomosed graft. Thereafter, distal anastomosis was performed proximal to the LSCA. RESULTS: The postoperative course was uneventful. DISCUSSION: Our reconstruction technique provides excellent exposure of the LSCA by pulling the origin of the LSCA caudally. Hemostasis after reconstruction is feasible, as the anastomosis in the anterior wall of the LSCA is easily visualized. CONCLUSION: The end-to-side anastomosis technique for LSCA reconstruction is a simple alternative in arch repair.

Covered frozen elephant trunk technique for prevention of distal stent graft-induced new entry.

Distal stent graft-induced new entry is not rare after frozen elephant trunk implantation. We report a case of covered frozen elephant trunk placement for prevention of distal stent graft-induced new entry. Coverage of the rigid distal stent edge using a graft reduces mechanical stress on the intima and radial force of the distal stent; therefore, this technique can potentially prevent distal stent graft-induced new entry.

Bail-Out Pull-Through Pull-Back Technique for Accidental Coverage of the Left Common Carotid Artery During Thoracic Endovascular Aortic Repair.

PURPOSE: We describe a pull-through pull-back technique to revascularize the left common carotid artery (LCCA) that was unintentionally covered during thoracic endovascular aortic repair (TEVAR). CASE REPORT: A 69-year-old man presented with back pain secondary to acute type B aortic dissection with an intimal tear in the proximal descending aorta. Serial computed tomography (CT) revealed an enlarged descending aorta and proximal progression of the aortic dissection. He underwent left carotid-subclavian artery bypass and TEVAR, 10 days after admission. The Valiant Navion stent graft without a bare stent was deployed proximally; however, the LCCA was unintentionally covered by the stent graft during this procedure. A pull-through form was created between the left axillary and femoral arteries using a 0.035-inch guide wire. The pull-through guide wire was gently pulled, and the greater curvature of the proximal end of the stent graft was displaced distally. Angiography confirmed restoration of antegrade blood flow into the LCCA. The patient's postoperative course was uneventful. Follow-up CT performed 6 months postoperatively confirmed preserved blood flow into the LCCA without endoleak nor stent migration. CONCLUSION: The pull-through pull-back technique is a feasible troubleshooting strategy for accidental coverage of supra-aortic vessels during TEVAR.

Influence of residual primary entry following the tear-oriented strategy for acute type A aortic dissection.

OBJECTIVES: Although a tear-oriented strategy has contributed to improving short-term surgical outcomes of acute type A aortic dissection (ATAAD), long-term clinical influences of residual entry tear in the downstream aorta have not been fully investigated. The goal of this study was to assess the long-term surgical outcomes of ATAAD with or without a residual entry tear in the downstream aorta. METHODS: Medical records of 1107 patients with ATAAD who underwent emergency surgery between 1990 and 2018 were retrospectively reviewed. A tear-oriented paradigm was adopted for the baseline strategy. The 837 patients in whom the entry tears were resected comprised the resected group, and the 270 patients with a residual entry tear comprised the residual group. Of these patients, 252 in each group were analysed using propensity score matching, and long-term outcomes were compared with or without residual entry. RESULTS: Hospital deaths were lower in the resected group (3.2% vs 8.3%; P = 0.020). The survival rate was not significantly different between the groups: It was 83.8% and 68.5% in the resected group and 80.2% and 66.5% in the residual group at 5 and 10 years, respectively (P = 0.600). However, residual entry in the downstream aorta affected the distal aortic event-free survival rate (90.4% and 80.6% in the resected group and 82.3% and 67.4% in the residual group at 5 and 10 years, respectively; P = 0.003). Furthermore, multivariable risk analysis of 1107 patients confirmed that a residual entry in the downstream aorta was a risk factor for distal aortic events. CONCLUSIONS: The tear-oriented strategy remains the gold standard for high-risk patients; however, the extensive operation might be considered for stable patients to reduce long-term aortic events.

Total arch and descending aorta replacement via left thoracotomy for infected post-thoracic endovascular aortic repair type B aortic dissection.

A 38-year-old man underwent thoracic endovascular aortic repair for impending rupture of acute type B aortic dissection. Computed tomography revealed abscess formation around the proximal descending aorta 4 weeks after endovascular treatment. He underwent one-stage total arch and descending aorta replacement and omental wrapping via left thoracotomy. At the 6-month follow-up, his postoperative course was uneventful.

Double-patch and glue repair of a postinfarction left ventricular pseudoaneurysm.

An 85-year-old man with appetite loss, lightheadedness, and leg edema was referred to our institution. Computed tomography and transthoracic echocardiography revealed a left ventricular pseudoaneurysm with a maximal diameter of 80 mm and severe mitral regurgitation. Coronary angiography showed 90% stenosis and total occlusion of the left circumflex artery at segments 11 and 12, respectively. He was diagnosed with postinfarction left ventricular pseudoaneurysm and underwent patch repair using two bovine pericardium patches and biological glue, mitral valve replacement, and coronary artery bypass grafting. His postoperative course was uneventful.

Clinical outcomes of a fenestrated frozen elephant trunk technique for acute type A aortic dissection.

OBJECTIVES: We investigated the outcomes of a fenestrated frozen elephant trunk (FET) technique performed without reconstruction of one or more supra-aortic vessels for aortic repair in patients with acute type A aortic dissection. METHODS: We investigated 22 patients who underwent the fenestrated FET technique for acute type A aortic dissection at our hospital between December 2017 and April 2020. The most common symptom was chest pain and/or back pain. Nine patients presented with malperfusion and 1 with cardiac arrest, preoperatively. A FET was deployed under hypothermic circulatory arrest and manually fenestrated under direct vision. Single fenestration was made in the FET in 15 patients, 2 fenestrations in 5 patients and a total fenestrated technique in 2 patients. Concomitant procedures were performed in 5 patients. RESULTS: The cardiopulmonary bypass, aortic cross-clamp and hypothermic circulatory arrest times were 181 ± 49, 106 ± 43 and 37 ± 7 min, respectively. In-hospital mortality, stroke, or recurrent nerve injury did not occur in any patient. One patient developed paraparesis, which completely recovered at discharge. During the follow-up period (mean 18 ± 7 months), 1 patient died of heart failure. Fenestration site occlusion did not occur. Follow-up computed tomography (mean 12 ± 6 months postoperatively) revealed that the maximal aortic diameter remained unchanged at the levels of the distal end of the FET, the 10th thoracic vertebra and the coeliac artery; however, the aortic diameter was significantly reduced at the level of the pulmonary artery bifurcation. CONCLUSIONS: The fenestrated FET technique is a simple, safe and effective procedure for selected patients with acute type A aortic dissection.

Clinical outcome of acute thoracic aortic syndrome in nonagenarians.

BACKGROUND: Decision-making regarding the operability of thoracic aortic disease in nonagenarian patients remains controversial because outcomes of open surgical repair of the thoracic aorta are unclear. We investigated the surgical and nonsurgical outcomes of acute thoracic aortic syndrome treatment in nonagenarians. METHODS: After evaluating data in our institute from April 2016 to March 2020, we included 10 nonagenarians who needed surgical intervention on the thoracic aorta via a median sternotomy for acute thoracic aortic syndrome. The mean age of the cohort was 91.9 ± 2.1 years. Five patients underwent open surgical repair of the thoracic aorta (surgical group), and 5 refused surgery (nonsurgical group). All patients in the surgical group performed activities of daily living independently, with a mean clinical frailty scale of 3.2 ± 0.4. The surgical group included 4 patients with type A aortic dissection and one with a ruptured thoracic aortic aneurysm. Hemiarch replacement was performed in 3 patients and total arch replacement in 2. The mean follow-up period was 17.8 ± 5.1 months. RESULTS: Hospital mortality rates were 0% in the surgical and 80% in the nonsurgical group. The mean length of hospitalization was 28.4 ± 6.7 days in the surgical group. The 1-year survival rates were 100% in the surgical group and 20% in the nonsurgical group. CONCLUSION: Open surgical repair for acute thoracic aortic syndrome via median sternotomy is a reasonable treatment option even in nonagenarians. Involvement of family members is important for decision-making to devise the optimal treatment strategy (surgical vs. medical).

Staged treatments of multiple pseudoaneurysms after total arch replacement.

BACKGROUND: An aortic pseudoaneurysm after cardiovascular surgery can be fatal. METHODS/RESULTS: Here, we describe the staged successful treatments of three pseudoaneurysms in a 77-year-old female patient who underwent total arch replacement and coronary artery bypass grafting 5 years ago. Computed tomography revealed three pseudoaneurysms: in the distal anastomosis of the total arch replacement, in the anastomosis of the left common carotid artery, and in the proximal anastomosis of the saphenous vein graft. Endovascular treatment and surgical repair were performed to treat these three pseudoaneurysms. DISCUSSION: An aortic pseudoaneurysm is a rare complication after cardiac or aortic surgery. Here, we present a case of combined endovascular and surgical repairs of three pseudoaneurysms in one patient.

Incidence of postoperative atrial fibrillation in transdermal ß-blocker patch users is lower than that in oral ß-blocker users after cardiac and/or thoracic aortic surgery.

OBJECTIVE: Postoperative atrial fibrillation (POAF) after open heart surgery is associated with a high risk of mortality and morbidity. Although oral ß-blockers are usually recommended to prevent POAF, the efficacy of a transdermal ß-blocker patch in preventing POAF is unclear. We compared the incidence of POAF between users of oral and transdermal bisoprolol. METHODS: We investigated 108 patients who underwent cardiac and/or thoracic aortic surgery between April 2016 and February 2018. We compared perioperative clinical and hemodynamic variables between 49 patients treated with a transdermal bisoprolol patch and 59 patients treated with an oral bisoprolol fumarate. RESULTS: POAF occurred in 24% of patients in the transdermal and in 46% of patients in the oral bisoprolol groups (p = 0.027). No intergroup difference was observed in in-hospital mortality, perioperative blood pressures and heart rates, and other morbidities. Multivariable logistic regression analysis revealed that the use of transdermal bisoprolol was independently associated with a lower rate of POAF (odds ratio 0.21, 95% confidence interval 0.05-0.84, p = 0.027). CONCLUSIONS: A transdermal bisoprolol patch is an effective and safe ß-blocker drug delivery system. The incidence of POAF in this group was lower than that in users of oral bisoprolol.

The impact of preoperative sarcopenia, defined based on psoas muscle area, on long-term outcomes of heart valve surgery.

OBJECTIVE: Sarcopenia, age-related loss of muscle mass, is an objective and comprehensive marker of frailty. We aimed to clarify the influence of sarcopenia on the outcomes after heart valve surgery. METHODS: We retrospectively reviewed 1119 patients who underwent valve surgery via median sternotomy at our institution from June 2009 to December 2013. Patients aged <70 years, urgent/emergent cases, and patients without preoperative computed tomography of the abdomen were excluded. The remaining 428 patients were included in this study. Psoas muscle area, a validated measure of sarcopenia, was measured on preoperative computed tomography. Sarcopenia was defined as the lowest sex-specific quartile in psoas muscle area. The mean follow-up period was 3.4 years. RESULTS: Overall in-hospital mortality did not differ between the sarcopenia and nonsarcopenia patient groups. However, the incidence of stroke and intra-aortic balloon pump/percutaneous cardiopulmonary support use was greater in the sarcopenia group than in the nonsarcopenia group. The patients with sarcopenia had significantly decreased long-term survival and decreased freedom from major adverse cardiac and cerebrovascular events. Multivariable analysis and inverse probability weighting revealed that sarcopenia was an independent predictor for decreased survival (hazard ratio, 2.22; 95% confidence interval, 1.26-3.92; P = .006). CONCLUSIONS: Preoperative sarcopenia defined from the psoas muscle area was associated with long-term outcomes after valve surgery. Thus, the measurement of psoas muscle area can help facilitate more accurate risk scoring in elderly patients.

Postinfarction right ventricular wall dissection with left-to-right shunting.

Ventricular septal rupture is an uncommon fatal complication of acute myocardial infarction. In rare cases, the rupture can extend into the right ventricular free wall and cause intramyocardial dissection. We describe the case of a patient who developed postinfarction right ventricular free wall dissection with left-to-right shunting and successfully underwent patch repair.

Feasibility of low-frequency ultrasound imaging using pulse compressed parametric ultrasound.

When using high-frequency (HF) ultrasound in sonography, attenuation due to the viscosity of the medium limits the available imaging depth, and strong reflection and scattering from hard tissue, such as bone, render biological diagnosis very difficult. In order to resolve these problems, the feasibility of low-frequency (LF) parametric ultrasound imaging with high directivity was explored in the present study. A pulse compression technique was applied to chirp-modulated parametric ultrasound waves in the frequency band of 100-500 kHz generated from modulated primary ultrasound waves with a center frequency of 2.8 MHz in order to improve the signal-to-noise ratio (SNR). Low-frequency ultrasound images of brass rods obtained using pulse compressed parametric ultrasound exhibit accurate target distances, a 3-mm range resolution, which agrees well with the theoretical value, and an 8-dB improvement in SNR. Parametric ultrasound imaging with pulse compression makes easy to separate overlapping targets in comparison with HF ultrasound imaging, and indicates the image with brightness independent of distance in comparison with directly radiated LF ultrasound imaging. These results reveal that pulse compressed LF parametric ultrasound is not only a useful method for improving the SNR and providing accurate distance measurements, but also enables imaging of overlapping targets.