Optimal stent length and distal positioning of frozen elephant trunks deployed from the aortic zone 0 for type A acute aortic dissection.

OBJECTIVES: To investigate the optimal stent length and distal positioning of frozen elephant trunks (FETs) in patients with type A acute aortic dissection (TAAD). METHODS: Between October 2014 and April 2021, 191 patients (FET-150 group: 37 patients; stent length, 150 mm; 66.3 ± 12.6 years and FET-non-150 group: 154 patients; 60, 90, or 120 mm; 64.1 ± 12.5 years) underwent total arch repair with FETs for TAAD using the "zone 0 arch repair" strategy. In the FET-150 group, the proximal stent end was positioned at the innominate artery origin of the arch. In the FET-non-150 group, the distal stent end was to be positioned just proximal to the aortic valve level using transesophageal echocardiography. The proximal end of the non-stented FET part was sutured to an arch graft together with the aortic wall at 1 to 2 cm proximal to the innominate artery origin. RESULTS: Distal stent ends were positioned at the thoracic vertebrae (Th) 4-5, 6-7, 8-9, and 10 levels in 0 (0%), 12 (32.4%), 25 (67.6%), and 0 (0%) patients, respectively, in the FET-150 group, and in 6 (3.9%), 98 (63.6%), 49 (31.8%), and 1 (0.7%), respectively, in the FET-non-150 group. No between-group difference in postoperative mortality was noted. The incidence of postoperative residual distal malperfusion and new-onset spinal cord ischemia in the FET-150 versus FET-non-150 groups were 2.7% versus 6.5% (P = .62) and 0% versus 1.9% (P = 1.00), respectively. CONCLUSIONS: FET positioning with the distal stent end at around Th 8 can reduce residual distal malperfusion when a FET with a 150-mm stent is deployed from the aortic zone 0 in patients with TAAD undergoing total arch repair.

Bioinformatic Identification of Potential RNA Alterations on the Atrial Fibrillation Remodeling from Human Pulmonary Veins.

Atrial fibrillation (AF) is the most frequent persistent arrhythmia. Many genes have been reported as a genetic background for AF. However, most transcriptome analyses of AF are limited to the atrial samples and have not been evaluated by multiple cardiac regions. In this study, we analyzed the expression levels of protein-coding and long noncoding RNAs (lncRNAs) in six cardiac regions by RNA-seq. Samples were donated from six subjects with or without persistent AF for left atria, left atrial appendages, right atria, sinoatrial nodes, left ventricles, right ventricles, and pulmonary veins (PVs), and additional four right atrial appendages samples were collected from patients undergoing mitral valve replacement. In total, 23 AF samples were compared to 23 non-AF samples. Surprisingly, the most influenced heart region in gene expression by AF was the PV, not the atria. The ion channel-related gene set was significantly enriched upon analysis of these significant genes. In addition, some significant genes are cancer-related lncRNAs in PV in AF. A co-expression network analysis could detect the functional gene clusters. In particular, the cancer-related lncRNA, such as SAMMSON and FOXCUT, belong to the gene network with the cancer-related transcription factor FOXC1. Thus, they may also play an aggravating role in the pathogenesis of AF, similar to carcinogenesis. In the least, this study suggests that (1) RNA alteration is most intense in PVs and (2) post-transcriptional gene regulation by lncRNA may contribute to the progression of AF. Through the screening analysis across the six cardiac regions, the possibility that the PV region can play a role other than paroxysmal triggering in the pathogenesis of AF was demonstrated for the first time. Future research with an increase in the number of PV samples will lead to a novel understanding of the pathophysiology of AF.

Pulmonary Artery Intimal Sarcoma in a Patient with Lynch Syndrome: Response to an Immune Checkpoint Inhibitor.

Intimal sarcoma is an extremely rare mesenchymal tumor arising in the great vessels. To date, intimal sarcoma has not been reported in patients with Lynch syndrome (LS), even though this syndrome lacks DNA mismatch repair ability genetically and is prone to various malignancies. This patient was diagnosed with LS by the Revised Amsterdam Criteria II, and she suffered from intimal sarcoma in the left pulmonary artery. She had a germline missense variant of PMS2 (c.1399G>A, pV467I) which is classified as a variant of unknown significance. In her intimal sarcoma, PMS2 expression was decreased. Additionally, it exhibited microsatellite instability and a high tumor mutational burden (69 mutations/Mb) which are features of mismatch repair deficiency, although PMS2 (c.1399G>A, pV467I) missense is a variant of unknown significance. The metastatic lesions of intimal sarcoma in this patient responded heterogeneously to pembrolizumab, an immune checkpoint inhibitor. Cytotoxic agents and radiation were also effective for some metastatic lesions, but some lesions, including her liver metastases, were resistant. The hypermutable nature of the LS genotype might acquire resistance to an immune checkpoint inhibitor and other cytotoxic agents such as occurred with her liver metastases.

Impact of Early Ambulation on the Prognosis of Coronary Artery Bypass Grafting Patients.

BACKGROUND: The effect of delayed ambulation on the outcome of coronary artery bypass grafting (CABG) remains to be clarified.Methods and Results: The long-term and in-hospital outcomes of 887 patients who underwent isolated CABG (455 off-pump cases, 135 urgent cases) were evaluated, with a focus on the timing of first ambulation. In-hospital mortality cases were excluded. Early ambulation (first ambulation within 3 days after operation) was achieved in 339 (38%) patients. In the multivariable logistic regression analysis, longer operation time and urgent case, EuroSCORE II, re-thoracotomy, and respiratory time were associated with delayed (≥4 days) ambulation. Delayed ambulation was associated with a high incidence of postoperative complications, such as pneumonia, and stroke (P<0.01). Following discharge, 22.2% of patients experienced major cardiac events and 13.8% died during the follow-up period (median follow-up 60 months). Cox hazards analysis revealed that delayed ambulation was associated with long-term adverse events (hazard ratio 1.04 per day, P<0.001). With adjustment for preoperative factors, the estimated future risk of adverse events was found to be increased day-by-day during the delay until initial ambulation. CONCLUSIONS: In isolated CABG patients, delayed ambulation was associated with poor outcomes, even in the long-term period. The results support the current guideline recommending early ambulation protocol after cardiac surgery.

Aortic remodeling, reintervention, and survival after zone 0 arch repair with frozen elephant trunks for acute type A aortic dissection: Midterm results.

Objectives: To investigate the midterm results after zone 0 arch repair with frozen elephant trunks for acute type A aortic dissection. Methods: Between October 2014 and April 2021, 196 patients underwent zone 0 arch repair with frozen elephant trunks for acute type A aortic dissection. The true lumen area, aortic lumen area, and false lumen status were assessed at four aortic levels, the proximal and distal descending thoracic aorta (level A and level B, respectively), celiac artery branching (level C), and terminal aorta (level D). Aortic remodeling (postoperative area as a percentage of the preoperative area) was classified into 3 groups, positive (true lumen area ≥120% with aortic lumen <120% or true lumen area ≥80% with aortic lumen <80%), minimal (80% ≤ true lumen area and aortic lumen area <120%), and negative remodeling (all other changes). Results: In-hospital mortality was 13 (6.6%) patients. The overall survival rate was 85.1% at 5 years. The freedom from distal aortic reintervention was 89.9% at 5 years. The prevalence of completely thrombosed or obliterated false lumen at 2 years was 96.8% at level A, 88.4% at level B, 47.2% at level C, and 27.6% at level D. The prevalence of positive aortic remodeling at 2 years was 84.7% at level A, 75.0% at level B, 29.2% at level C, and 16.7% at level D. Conclusions: Zone 0 arch repair with frozen elephant trunks for acute type A aortic dissection can avoid invasive aortic arch resection and facilitate aortic remodeling of the descending thoracic aorta. The FET effect on aortic remodeling is limited at the aortic level below the FET stent end.

Enhanced strategy against mediastinitis with thoracic vascular graft infection: A combination of hydro-debridement with pulsed lavage and negative pressure wound therapies.

BACKGROUND: We investigated the effects of hydrodebridement with pulsed lavage (HDPL) and negative pressure (NP) wound therapies, instead of excising the prosthetic graft, in patients with postoperative thoracic vascular graft infection (TVGI). METHODS: Between 2020 and 2021, five TVGI patients aged 49.6 ± 19.4 years old underwent a combined therapy of HDPL and NP. The patients underwent a two-step procedure (first step: re-sternotomy and HDPL; second step: NP) every 3 or 4 days. After negative tissue culture, the patients underwent omentum flap wrapping and skin closure. RESULTS: No hospital death was observed. The time to skin closure was 10.8 ± 3.4 days. The time to the day in which bacteria were not cultured was 3.5 ± 2.4 days. No recurrent infections occurred for 241 ± 186 postoperative days. CONCLUSION: Our strategy for TVGI patients may contribute to (1) sufficient infection control, (2) physical rehabilitation, and (3) less invasiveness for high-risk patients.

Preferential Expression of Ca2+-Stimulable Adenylyl Cyclase III in the Supraventricular Area, including Arrhythmogenic Pulmonary Vein of the Rat Heart.

Ectopic excitability in pulmonary veins (PVs) is the major cause of atrial fibrillation. We previously reported that the inositol trisphosphate receptor in rat PV cardiomyocytes cooperates with the Na+-Ca2+ exchanger to provoke ectopic automaticity in response to norepinephrine. Here, we focused on adenylyl cyclase (AC) as another effector of norepinephrine stimulation. RT-PCR, immunohistochemistry, and Western blotting revealed that the abundant expression of Ca2+-stimulable AC3 was restricted to the supraventricular area, including the PVs. All the other AC isotypes hardly displayed any region-specific expressions. Immunostaining of isolated cardiomyocytes showed an enriched expression of AC3 along the t-tubules in PV myocytes. The cAMP-dependent response of L-type Ca2+ currents in the PV and LA cells is strengthened by the 0.1 mM intracellular Ca2+ condition, unlike in the ventricular cells. The norepinephrine-induced automaticity of PV cardiomyocytes was reversibly suppressed by 100 µM SQ22536, an adenine-like AC inhibitor. These findings suggest that the specific expression of AC3 along t-tubules may contribute to arrhythmogenic automaticity in rat PV cardiomyocytes.

Pacemaker Lead-induced Tricuspid Valve Stenosis and Reverse Lutembacher Syndrome.

Reverse Lutembacher syndrome is a rare cause of hypoxia characterized by the triad of tricuspid valve stenosis, elevated right atrial pressure, and an interatrial right-to-left shunt. We report a case of pacemaker lead-induced reverse Lutembacher syndrome in a 45-year-old woman who presented with dyspnea. The patient also developed pacemaker lead-induced superior vena cava obstruction accompanied by a right-to-left shunt through systemic-to-pulmonary venous collaterals, which exacerbated the hypoxia. Tricuspid valve replacement using a bioprosthetic valve and patent foramen ovale closure improved her hypoxia.

Right coronary ostium occlusion by aortic valve tumor during systole.

Here, we present a case of acute myocardial infarction caused by an aortic valve tumor. Electrocardiography (ECG)-gated four-dimensional computed tomography revealed obstruction of the right coronary ostium by a mobile mass during systole. To ensure an accurate diagnosis of angina in patients without significant coronary artery disease, ECG-gated four-dimensional computed tomography is useful because it can simultaneously visualize the coronary ostium and arteries, aortic valve leaflets, and mass.

Endovascular rescue for malpositioned frozen elephant trunk into the false lumen.

We describe a case of frozen elephant trunk deployment unintentionally malpositioned into the false lumen. An 83-year-old man underwent total arch repair with a frozen elephant trunk for type A acute aortic dissection complicated by mesenteric malperfusion. However, intraoperative transesophageal echocardiography showed expansion of the false lumen in the descending aorta, suggesting a malpositioned frozen elephant trunk into the false lumen. Endovascular fenestration of the dissecting flap and subsequent endograft deployment from the inside of the malpositioned frozen elephant trunk graft to the true lumen of the descending aorta was successfully performed under intravascular ultrasound guidance.

Ruptured type A aortic dissection with saddle pulmonary embolism-like appearance on computed tomography angiography.

We present a case of ruptured type A acute aortic dissection with pulmonary trunk compression by mediastinal hematoma. This condition mimicked a pulmonary embolism on the early arterial phase of computed tomography angiography, whereas the correct diagnosis was determined from the late arterial phase and unenhanced computed tomography. We highlight the importance of carefully interpreting triphasic computed tomography angiography to assess the status of aortic dissection.

[Traction-assisted Negative Pressure Wound Therapy for Pediatric Poststernotomy Mediastinitis:Report of Two Cases].

We herein report two cases of pediatric poststernotomy mediastinitis treated by traction-assisted negative pressure wound therapy (NPWT) with Zip Surgical Skin Closure (Zip), which is a non-invasive skin closure device. We used this device with NPWT in cases of pediatric poststernotomy mediastinitis to stabilize the sternum and reduce the natural retractive forces of the skin. The patients were two boys (two and three months old), with an onset of infection at 13 and eight postoperative days, respectively. The culture examination detected methicillin-susceptible Staphylococcus aureus in both cases. Traction-assisted NPWT with Zip was performed at-75 mmHg for 16 and 33 days, and the wounds healed completely. In conclusion, this modification was successfully applied to treat pediatric poststernotomy mediastinitis and may help reduce the duration of treatment.

Avoiding anticoagulation drugs for postoperative atrial fibrillation enabled successful conservative treatment of left atrial dissection: a case report.

BACKGROUND: Left atrial dissection is a rare complication of cardiac surgery, most commonly associated with mitral valve surgery. Herein, we report on the successful conservative treatment of left atrial dissection while avoiding anticoagulation therapy. CASE PRESENTATION: A 64-year-old man developed left atrial dissection during operation for acute type A aortic dissection, most likely due to retrograde cardioplegia cannulation. As there was no connection between the left atrial dissection cavity and the left atrium on enhanced computed tomography, we did not administer anticoagulants to prevent expansion of the left atrial dissection cavity. However, the patient developed atrial fibrillation, which was successfully managed by beta-blocker and amiodarone administration. Follow-up imaging showed gradual left atrial dissection reduction, and the patient was started on anticoagulation therapy. CONCLUSION: We were able to resolve left atrial dissection by preventing the use of anticoagulation therapy in the acute stage by managing the atrial fibrillation with antiarrhythmic drugs.

Secretory production of a camelid single-domain antibody (VHH, nanobody) by the Serratia marcescens Lip system in Escherichia coli.

Escherichia coli is one of the most popularly used hosts to produce recombinant proteins. Most recombinant proteins are produced in the cytoplasm and periplasm, requiring multiple steps to extract and purify recombinant proteins. The Serratia marcescens Lip system (LipB-LipC-LipD) is a type 1 secretion system that selectively secretes LipA from the intracellular to extracellular space in a single step. This study aimed to establish a secretory production system for nanobodies, camelid-derived small molecule antibody fragments, using the S. marcescens Lip system. Surprisingly, E. coli harboring only LipC, a membrane fusion protein of the Lip system, could secrete an anti-green fluorescent protein (GFP)-Nb, a nanobody against GFP, without the addition of a long amino acid sequence. The LipC-based secretion system recognized the Val-Thr-Val sequence at the C-terminus of the nanobody. Finally, Strep-tagged anti-GFP-Nb was purified from culture supernatants of E. coli harboring LipC by Strep-affinity chromatography at a final yield of >5 mg per liter of culture supernatant. These results potently supported that the S. marcescens LipC-based secretion system has the potential to establish an efficient secretory production system for nanobodies.

Calcified Aortic Wall Removal for Dysphagia Aortica Caused by Chronic Traumatic Aortic Pseudoaneurysm.

In this study, we report a case of a 45-year-old man with dysphagia aortica secondary to chronic traumatic aortic pseudoaneurysm of the aortic isthmus. He had been involved in a motor vehicle accident 27 years earlier. Computed tomography demonstrated a severely calcified aortic pseudoaneurysm of the aortic isthmus that compressed the esophagus extrinsically. An invasive surgical procedure involving a graft replacement and removal of the calcified aortic wall released the esophageal compression and completely improved the patient's symptoms. To the best of our knowledge, a case of dysphagia aortica caused by calcified pseudoaneurysm has never been reported.

Direct Abdominal Aortic Access for Thoracic Endovascular Aortic Repair in a Patient with Severe Aortic and Arterial Calcification.

Aortic and arterial calcification is a complication of advanced atherosclerosis and is a critical intraoperative issue that can reduce the ability to achieve safe and adequate access for stent graft introduction. Different vascular access sites are used to deliver stent grafts when a standard transfemoral or iliac access is not feasible. We report a challenging case of a direct transabdominal aortic thoracic endovascular aortic repair for a thoracic aortic aneurysm complicated with severe aortic and arterial calcification, in which the noncalcified area of the infrarenal abdominal aorta was extremely limited. This may be a reasonable access site, especially for patients with severe aortic and arterial calcification.

[Thoracic Endovascular Repair for Chronic Aortic Dissection with Aberrant Origin of the Left Vertebral Artery;Report of a Case].

We herein report a case of thoracic endovascular aortic repair( TEVAR) for chronic aortic dissection with an aberrant left vertebral artery( LVA) originating from the aortic arch. A 51-year-old man with a medical history of Stanford type B acute aortic dissection 2 years ago was transferred to our institution for the treatment of an aortic expansion. Computed tomography showed a large entry just distal to the takeoff of the left subclavian artery and a dilated dissected thoracic aorta. A left cervical incision over the anterior border of the sternocleidomastoid was made, and the LVA was identified. The proximal LVA was ligated and anastomosed to the left common carotid artery in an end-to-side fashion. After completion of the carotid-subclavian bypass, TEVAR was performed in the usual fashion. The postoperative course was uneventful without stroke or spinal cord injury. At the 1-year follow-up, the false lumen had shrunk and the LVA remained patent.

[Tricuspid Valve Replacement Preserving the Leaflets in a Congenitally Corrected Transposition of the Great Arteries;Report of a Case].

In patients with a congenitally corrected transposition of the great arteries (ccTGA), the regurgitation of the systemic atrioventricular valve (SAVV) increases and anatomical right ventricular (ARV) dysfunction often progressively develops. A low systemic ventricular ejection fraction( SVEF) is a risk factor for mortality. However, in patients with a low ejection fraction of ARV, it is unclear how to best perform valve replacement for patients with regurgitation of SAVV. A 70-year-old female with respirator discomfort was admitted to our hospital and diagnosed to have situs solitus ccTGA, severe SAVV regurgitation, and ARV dysfunction. Her ARV ejection fraction was 25% and she was therefore dependent on inotropic agents. We successfully performed a tricuspid valve replacement while preserving the leaflets, the chorda tendineae's, and papillary muscles, and placing the lead for cardiac resynchronization therapy on the ARV. Her postoperative course was uneventful. Thereafter, she was discharged 6 weeks after surgery.