Identification of B.1.346 Lineage of SARS-CoV-2 in Japan: Genomic Evidence of Re-entry of Clade 20C.

SARS-CoV-2 whole-genome sequencing of samples from COVID-19 patients is useful for informing infection control. Datasets of these genomes assembled from multiple hospitals can give critical clues to regional or national trends in infection. Herein, we report a lineage summary based on data collected from hospitals located in the Tokyo metropolitan area. We performed SARS-CoV-2 whole-genome sequencing of specimens from 198 patients with COVID-19 at 13 collaborating hospitals located in the Kanto region. Phylogenetic analysis and fingerprinting of the nucleotide substitutions were performed to differentiate and classify the viral lineages. More than 90% of the identified strains belonged to Clade 20B, which has been prevalent in European countries since March 2020. Only two lineages (B.1.1.284 and B.1.1.214) were found to be predominant in Japan. However, one sample from a COVID-19 patient admitted to a hospital in the Kanto region in November 2020 belonged to the B.1.346 lineage of Clade 20C, which has been prevalent in the western United States since November 2020. The patient had no history of overseas travel or any known contact with anyone who had travelled abroad. Consequently, the Clade 20C strain belonging to the B.1.346 lineage appeared likely to have been imported from the western United States to Japan across the strict quarantine barrier. B.1.1.284 and B.1.1.214 lineages were found to be predominant in the Kanto region, but a single case of the B.1.346 lineage of clade 20C, probably imported from the western United States, was also identified. These results illustrate that a decentralized network of hospitals offers significant advantages as a highly responsive system for monitoring regional molecular epidemiologic trends.

Thoracic Endovascular Aortic Repair Including Total Debranching on Femoral Artery for Arch Rupture.

A 94-year-old woman with rupture of a thoracic aortic aneurysm (rTAA) was referred to us. She previously underwent thoracic endovascular aortic repair and was considered to be at high risk for a conventional open operation. Therefore an endovascular procedure was planned. The proximal landing zone needed to be placed at the ascending aorta to seal a type 1a endoleak. A hybrid operation consisting of supraaortic total debranching on the common femoral artery and endovascular repair was performed. All debranched bypasses were patent and the aneurysm was excluded. The patient regained sufficient ambulatory strength and showed no symptoms of syncope.

Total thoracoscopic left ventricular lead implantation for hybrid cardiac resynchronization therapy in pacemaker-mediated cardiomyopathy.

Cardiac resynchronization therapy (CRT) has been increasingly performed in patients having heart failure with dyssynchrony. We report a successful case of total thoracoscopic left ventricular (LV) lead implantation in CRT. A 77-year-old man with marked dyssynchrony of the LV wall motion and a low ejection fraction (EF17%) due to pacemaker-mediated cardiomyopathy was referred to us. CRT was planned, but percutaneous LV lead implantation proved difficult owing to anatomical variations. The LV lead was placed in the post-lateral wall of the LV base using a total thoracoscopic procedure. Preoperative dyspnea and dyssynchrony were clearly improved. In CRT, the LV wall stimulation site is important. The LV lead should be implanted in the latest activation area, which can be detected using speckle tracking echocardiography. Surgical lead implantation can be performed in the ideal area, and this procedure may play a new role as a hybrid CRT.

Surgical Strategy for Thoracic Aortic Pseudoaneurysm with Sternal Adherence.

A thoracic aortic pseudoaneurysm is a life-threatening complication following thoracic aortic surgery. We describe a surgical strategy for this pseudoaneurysm with a high risk for rupture during median sternotomy. The pseudoaneurysm was distended and widely adherent to the posterior sternum. Elective cardiopulmonary bypass and moderate hypothermia were established, and sternotomy was performed without left ventricle distention or brain ischemia. Total arch replacement was successful and the patient was discharged on post operative day (POD) 18. A key surgical strategy was to avoid ventricular fibrillation before sternotomy. Appropriate sternotomy timing and perfusion strategy are crucial for successful treatment.

Peripartum Type A Aortic Dissection Repair Using Frozen Elephant Trunk Technique.

A 43-year-old woman with abdominal and back pain during childbirth consulted us 1 day postdelivery. Contrast-enhanced computed tomography (CT) revealed partially thrombosed type A aortic dissection with intimal tear in the proximal descending thoracic aorta. Conservative antihypertensive treatment was started. However, her abdominal pain progressively deteriorated. Repeat CT revealed narrowing of the descending aorta true lumen and progressive bowel malperfusion. Total arch replacement was urgently performed using the frozen elephant trunk technique. Postoperative CT showed true lumen widening and symptom disappearance. Follow-up CT demonstrated excellent aortic remodeling.

A surgical case of ventricular septal perforation after repairing left ventricular free wall rupture.

A 78-year-old woman with diagnosis of acute myocardial infarction (AMI) in the anteroseptal area fell into cardiogenic shock suddenly just before starting percutaneous coronary intervention (PCI). Echocardiography showed left ventricular free wall rupture, then an emergent operation was performed by sutureless patch repair using collagen fleece with fibrinogen-based impregnation. Eight days later from the initial operation, the onset of ventricular septal perforation (VSP) was recognized. Fifteen days after, the infarct exclusion technique with endocardial patch was performed. She has been doing well 4 months after the operation without residual shunt. To our best knowledge, this is the first surgical case report that free wall rupture of left ventricle and VSP which are serious complications after myocardial infarction happened in succession.

Giant left ventricular pseudo-false aneurysm following myocardial infarction.

We report a successful surgical case of giant left ventricular pseudo-false aneurysm in a 63-year-old man. The abnormality of the inferior wall of the left ventricle was discovered incidentally by abdominal ultrasonography for health examination at another hospital. Transthoracic echocardiography and left ventriculography revealed a giant false aneurysm (74x75x40 mm) in the inferior wall of the left ventricle with a large orifice (70x58 mm). Repair of the aneurysm was performed under arrested heart, closing the large orifice with a Hemashield patch. Postoperative pathological examination proved that the wall of the aneurysm had myocardial tissue. The microscopic results strongly suggested that this aneurysm was a pseudo-false aneurysm.

Reoperation for a Starr-Edwards aortic prosthetic valve 33 years after initial implantation.

A 40-year-old woman admitted with heart failure had undergone aortic valve replacement with a Model 2310 Starr-Edwards valve due to aortic regurgitation 33 years previously. She had been followed up for several years, but discontinued follow-up and medication (including Warfarin) for the past 25 years. Echocardiography demonstrated marked dilatation and thickening of the left ventricle, and the peak pressure gradient of the prosthesis was measured as 87.9 mmHg. Under the diagnosis of chronic aortic valve prosthesis-patient mismatch with subsequent severe left ventricular dysfunction, the Starr-Edwards valve was explanted and replaced with a 23 mm St. Jude Medical prosthetic valve. The removed valve showed minimal cloth wear except for a small part of the strut. The postoperative echocardiography demonstrated recovering of left ventricular function. To our best knowledge, this case presents the longest duration for a surgically explanted Starr-Edwards aortic prosthetic valve in Japan.

Postoperative usage of tolvaptan in a patient with aortic valve stenosis complicated by Child-Pugh classification B liver cirrhosis and hepatic edema.

We report the case of an 80-year-old woman with postoperative congestive heart failure (CHF) complicated by Child-Pugh classification B liver cirrhosis and hepatic edema successfully treated with tolvaptan. The patient suffered from liver cirrhosis and underwent partial hepatectomy for a hepatocellular carcinoma diagnosed together with a severe aortic valve stenosis. Aortic valve replacement was performed under cardiopulmonary bypass. The postoperative course was uneventful until CHF and hepatic edema symptoms appeared on postoperative day (POD) 2. The symptoms were treated with intravenous human atrial natriuretic peptide and oral diuretics. As the condition showed no improvement, oral tolvaptan was administered on POD 11 and thereafter, which markedly improved the symptoms. This is apparently the first report describing the effectiveness of tolvaptan for the postoperative management of fluid balance in a patient with cardiac and liver dysfunction.

Repair of Acute Type B Aortic Dissection Complicated by Aortic Rupture with Debranching Thoracic Endovascular Aortic Repair and Left Subclavian Artery Occlusion Using Amplatzer Vascular Plug II.

An 88-year-old man with severe chest pain and syncope was admitted to our hospital. Contrast-enhanced computed tomography (CT) revealed acute type B aortic dissection with rupture. Considering age and operative risk, we performed emergency thoracic aortic endovascular repair with two-debranching of the left common carotid and left subclavian arteries. To prevent type II endoleak, we used Amplatzer Vascular Plug (AVP) II for left subclavian artery embolization. Postoperative contrast-enhanced CT showed no type II endoleak and rupture site exclusion. As postoperative persistent blood flow to the primary entry or rupture site causes re-rupture, AVP II was crucial in preventing type II endoleak.

Acute aortic dissection involving an aberrant right subclavian artery.

Although the aberrant right subclavian artery is the most common abnormality in aortic arch development, it is unusual to encounter this abnormality when repairing acute aortic dissection. We report a case of Stanford type A acute aortic dissection involving an aberrant right subclavian artery in a 45-year-old man. We used the elephant trunk procedure to surgically manage the intimal tear and aberrant right subclavian artery. This is, to our knowledge, the first report in Japan of surgical reconstruction of an aberrant right subclavian artery in conjunction with acute aortic dissection.

Floating ball thrombus in the left atrium with mitral stenosis.

We report a case of a floating ball thrombus in the left atrium with mitral stenosis in a 76-year-old woman. The patient had been followed-up at our hospital due to mitral valve stenosis for several years, and was recognized to have atrial fibrillation and a left atrial mural thrombus by echocardiography. She was admitted to our hospital for right cerebral infarction. Echocardiography showed a floating ball thrombus in the left atrium. After the treatment of cerebral infarction, she was referred to cardiac surgery, and a semi-urgent operation was performed. Removal of the ball thrombus and mitral valve replacement were performed simultaneously. The thrombus was single, round, soft, relatively smooth surfaced, and about 30 x 30 x 30 mm in diameter. The postoperative course was uneventful. Left atrial ball thrombus appears to be uncommon. This is a rare case, in which it was documented that a pre-existing left atrial mural thrombus was thought to drop off spontaneously, to be a cerebral embolic source, and to develop into a ball thrombus in the left atrium.

Intermittent circulatory arrest for repairing postoperative mycotic pseudoaneurysm in the ascending aorta.

Postoperative mycotic pseudoaneurysm in the ascending aorta associated with mediastinitis is one of the most serious complications after cardiovascular surgery. Circulatory arrest is usually needed for repairing this lesion; it is likely that the procedure needs unpredictably prolonged arrest time due to uncontrollable bleeding or serious adhesion. With this reason we employed intermittent circulatory arrest instead. The purpose of this paper is to describe 2 cases which demonstrated the method of intermittent circulatory arrest for repairing postoperative mycotic pseudoaneurysm in the ascending aorta.

Intraoperative trans-mitral endoscopic resection of left ventricular tumor.

A successful resection of left ventricular tumor in an 82-year-old woman who had undergone coronary artery bypass grafting ten years ago is presented. In an attempt to make a procedure less invasive, we chose a trans-mitral endoscopic resection with minimum dissection because of reoperation on patient of advanced age. With the use of cardiopulmonary bypass and cardioplegic protection, the right side of left atrium was incised longitudinally. The endoscope was inserted in the ventricle via the mitral valve. A stalk of the tumor was cut by snare strangulation and the whole tumor was extracted endoscopically. The postoperative course was uneventful. To our best knowledge, this is the first report on endoscopic resection of the left ventricular tumor via a mitral valve. This method appear to be the choice in resecting the left ventricular tumor.

Long-term outcomes and comparison after conventional coronary artery bypass grafting for left main disease between patients classified as percutaneous coronary intervention recommendation classes II and III.

OBJECTIVES: We retrospectively analysed long-term outcomes after conventional coronary artery bypass grafting (CABG) between patients having left main (LM) disease who should have been assigned class II and those assigned class III recommendation for percutaneous coronary intervention (PCI) according to the 2010 European Society of Cardiology and the European Association for Cardio-Thoracic Surgery guidelines. METHODS: From January 2000 to December 2009, conventional CABG was routinely employed in 180 consecutive patients with previously untreated and stable LM lesion. A comparison between two groups (CABG for PCI class II and CABG for PCI class III) was performed, looking at the primary endpoint of major adverse cardiac and cerebrovascular events (MACCE), including all-cause death, stroke [cerebral vascular accident (CVA)], myocardial infarction (MI) and repeat revascularization. We also analysed the effects of variables on MACCE at 8 years after the operation. RESULTS: The overall 8-year MACCE rates were significantly lower in the CABG for PCI class II group than in the CABG for PCI class III group (9.7% class II vs 31.1% class III; P = 0.0005). This was largely because of an increased rate of repeat revascularization (1.2% class II vs 13.8% class III; P = 0.0029). The cumulative rate of the combined outcomes of all death/CVA/MI was significantly lower in the CABG for PCI class II group (8.5% class II vs 19.2% class III; P = 0.048); there was no observed difference between the groups for all-cause death, CVA and MI. The SYNTAX score was demonstrated to be the only significant predictor of combined outcomes (Death/CVA/MI) at 8 years [odds ratio (OR) 1.05, P = 0.023], repeat revascularization at 8 years (OR 1.11, P = 0.0013) and MACCE at 8 years (OR 1.07, P < 0.0001). CONCLUSIONS: In our routine strategy of conventional CABG for LM disease, patients believed to be PCI candidates for LM disease have significantly better long-term outcomes as characterized by combined outcomes (Death/CVA/MI), repeat revascularization and MACCE. These results provide a suitable benchmark against which long-term outcomes of PCI for LM disease can be compared. The SYNTAX score, which was introduced to determine treatment for complex coronary disease, is indicative of long-term outcomes after CABG for LM disease.

A case of in-situ reconstruction with a rifampicin-bonded gelatin-sealed woven dacron graft for prosthetic graft infection with pseudoaneurysms after ascending aortic replacement for type a dissection.

A 74-year-old woman underwent replacement of the ascending aorta for acute type A aortic dissection. The patient suffered from bacteremia postoperatively and repeated computed tomography showed an increasing diameter of pseudoaneurysms at the site of the proximal anastomosis due to graft infection. Re-mechanical Bentall operation and arch replacement were therefore performed using a composite graft of a rifampicin-bonded gelatin-sealed 24-mm woven Dacron graft and a mechanical valve. The postoperative course was uneventful. We report the successful in situ reconstruction using the above-mentioned Dacron graft and describe the preparation of the rifampicin solution using a surfactant.

Successful detection and surgical treatment of cardiac hemangioma with right ventricular invasion.

Cardiac hemangiomas are extremely rare benign tumors. These tumors are usually asymptomatic but they can present symptoms such as palpitations, shortness of breath, and arrythmia. We report the case of a 73-year-old man who presented with an abnormal shadow on chest computed tomography during follow-up for lung metastatic tumor after resection of his rectal cancer. A cardiac tumor was detected, and surgical resection and right ventricular plasty were successfully performed with the patient under cardiopulmonary bypass. Histopathologic examination revealed a benign cardiac hemangioma, which was categorized as a hemangioma of the mixed cavernous and capillary type.