Chronic Dissecting Abdominal Aortic Aneurysm Coexisting with Horseshoe Kidney Requiring Supra-Renal Clamp and Reattachment of Accessory Renal Arteries / 日本心臓血管外科学会雑誌

A 60-year-old man underwent open surgery for chronic dissecting abdominal aorta accompanied with a horseshoe kidney. Through open laparotomy, the abdominal aortic aneurysm was exposed without revision of the horseshoe kidney. Cold ringer solution was infused to accessory renal arteries for renal protection. After supra-renal clamping, proximal anastomosis was then performed at the level just below the renal arteries. Abdominal cross clamp time at the level of the supra-renal arteries was 23 min. Median and right accessory arteries were reattached with an ischemic time of 73 and 103 min, respectively. Although serum creatine was elevated a preoperative level of 1.17 mg/dl to 3.63 mg/dl at postoperative day 2, that was gradually decreased to nearly preoperative level of 1.25 mg/dl at discharge. Postoperative enhanced CT demonstrated patency of the reattached accessory arteries. The patient was discharged without major complication on postoperative day 21. One year postoperatively, his follow-up course was uneventful without deterioration of renal function.

Identification, crystallization and epitope determination of public TCR shared and expanded in COVID-19 patients

T cells play pivotal roles in protective immunity against SARS-CoV-2 infection. Follicular helper T (Tfh) cells mediate the production of antigen-specific antibodies; however, T cell receptor (TCR) clonotypes used by SARS-CoV-2-specific Tfh cells have not been well characterized. Here, we first identified and crystallized public TCR of Tfh clonotypes that are shared and expanded in unhospitalized COVID-19-recovered patients. These clonotypes preferentially recognized SARS-CoV-2 spike (S) protein epitopes which are conserved among emerging SARS-CoV-2 variants. These clonotypes did not react with S proteins derived from common cold human coronaviruses, but cross-reacted with symbiotic bacteria, which might confer the publicity. Among SARS-CoV-2 S epitopes, S864-882, presented by frequent HLA-DR alleles, could activate multiple public Tfh clonotypes in COVID-19-recovered patients. Furthermore, S864-882-loaded HLA tetramer preferentially bound to CD4+ T cells expressing CXCR5. In this study, we identified and crystallized public TCR for SARS-CoV-2 that may contribute to the prevention of COVID-19 aggravation.

Aortic Root Replacement with a Valve Sparing Technique for Quadricuspid Aortic Valve / 日本心臓血管外科学会雑誌

A 67-year-old man with ascending aortic aneurysm was referred to our hospital. Transthoracic echocardiography showed severe aortic regurgitation with annuloaortic ectasia and transesophageal echocardiography revealed a quadricuspid aortic valve. This patient underwent aortic root replacement with a valve sparing technique. Under deep hypothermic circulatory arrest with retrograde cerebral perfusion, replacement of the ascending aorta was successfully performed. The postoperative course was uneventful. This patient is doing well 6 months after surgery without recurrence of aortic regurgitation.

Aortic Valve Replacement in Patients Aged 80 or Older / 日本心臓血管外科学会雑誌

With the progressive aging of the Japanese population, cardiac surgeons are increasingly faced with elderly patients. We have studied 29 consecutive patients, 80 years of age or older, who underwent aortic valve replacement at our institution between January 2000 and December 2003. Mortality, morbidity and late follow-up results were compared to those in 36 patients aged from 64 to 75 years old undergoing the same procedure over the same time period. The older patient group had a significantly higher incidence of calcified aortic stenosis and emergency operations and a higher score of NYHA functional class. Hospital mortality was 2 of 29 (6.9%) in the older patient group and 2 of 36 (5.6%) in the control group (ns). Postoperative renal failure and respiratory failure which needed prolonged ventilator support occured significantly more often in the older patient group. However, there was no significant difference between the 2 groups in terms of hospital stay. Almost all octogenarians showed improved NYHA functional class to class I or II after the operations. The actuarial survival rate was 89% in the older patient group and 78% in the control group at 3 years. The late survival rate and cardiac event-free rate were not significantly different between these 2 groups. Following aortic valve replacement, octogenarians, despite more compromised pre-operative status had good relief of symptoms, a favorable quality of life and a similar late survival to the younger patient groups. These findings support the recommendation that valve replacement should be performed in octogenarians with symptomatic aortic valvular disease.

A Case of Successful Transaortic Endovascular Stent Grafting for Distal Aortic Arch Aneurysm with Severely Calcified Chronic Aortic Dissection / 日本心臓血管外科学会雑誌

A 74-year-old man was admitted to our hospital to undergo an operation for distal aortic arch aneurysm with chronic aortic dissection. The first operation was attempted through left lateral thoracotomy. Since the aorta had a severely calcified false lumen, conventional aortic replacement was considered to entail greater risk and graft replacement was given up. As an another option, endovascular stent grafting via the aortic arch through median sternotomy was selected as a second operation. Deep hypothermic circulatory arrest with selective cerebral perfusion was used during delivery and deployment of the stented graft through the aortotomy site. The distal stented graft was deployed into the true lumen at the ninth thoracic vertebral level. Neither endoleaks nor complications were observed. Postoperative computed tomography showed complete thrombosis of the distal aortic arch aneurysm and the false lumen. The postoperative course was uneventful. Transaortic endovascular stent grafting is an effective and less invasive treatment for aortic arch aneurysms with severely calcified aorta.