Postoperative anticoagulation management using subcutaneous unfractionated heparin for a patient with nonbacterial thrombotic endocarditis: a case report.

Nonbacterial thrombotic endocarditis (NBTE) presents nonbacterial vegetation on cardiac valves. NBTE requires appropriate anticoagulant therapy to prevent recurrence after surgery. However, there has not yet been established evidence for anticoagulant therapy in NBTE, and low molecular weight heparin is not approved in Japan. We present a case of NBTE that was successfully managed with anticoagulant therapy using subcutaneous unfractionated heparin. A 59-year-old woman was diagnosed with NBTE on the mitral and tricuspid valve associated with breast cancer, underwent valve replacement. Warfarin and continuous intravenous unfractionated heparin were started. However, disseminated intravascular coagulation occurred after heparin was discontinued. Continuous intravenous unfractionated heparin injection was resumed immediately, and subcutaneous unfractionated heparin was administered before discharge. Postoperative echocardiography revealed no vegetation on the prosthetic valves thereafter. Subcutaneous unfractionated heparin therapy is useful to prevent the recurrence of NBTE as the anticoagulation in outpatients.

Mitral valve repair using a semi-rigid posterior band: a 10-year Japanese single-center experience of 244 patients.

Background: Mitral valve repair (MVr) is an established procedure for patients who require surgery for primary mitral regurgitation (PMR). The Colvin-Galloway Future Band (CGFB) is a semi-rigid posterior band expected to improve the clinical outcomes of MVr. However, information on the hemodynamic and functional performance and long-term outcomes of CGFB is limited. We evaluated the quality, durability, and clinical performance after MVr using CGFB for PMR as the cohort study. Methods: A total of 244 patients who underwent MVr with CGFB were enrolled. Clinical and echocardiographic assessments were performed (mean follow-up period, 4.0±2.4 years). Results: Posterior mitral leaflet resection was the most common MVr procedure. CGFBs measuring 28 mm (35.2%) and 30 mm (36.5%) were used. The incidence of systolic anterior motion (SAM) was 1.6%. A total of 93.4% of the patients had no or trace MR at discharge. Over 90% of patients had no or mild MR at the last follow-up. The mean pressure gradient and mitral valve orifice area one year after MVr ranged between 2.6 and 3.6 mmHg and 2.3 and 3.4 cm2, respectively. At follow-up, 85.4% of the patients were New York Heart Association class I. Three patients underwent repeat mitral valve surgery. Conclusions: The CGFB demonstrates satisfactory quality and durability in MVr for PMR. Other advantages include a low occurrence of SAM and acceptable hemodynamic outcomes, particularly in patients requiring a smaller annuloplasty device.

Early thrombus formation including hypo-attenuated leaflet thrombosis after surgical bioprosthetic aortic valve replacement.

OBJECTIVE: To assess the occurrence, predictors, and outcomes of hypo-attenuated leaflet thickening (HALT) and thrombus outside the prosthetic valve following surgical aortic valve replacement. METHODS: A total of 118 patients underwent surgical aortic valve replacement with bioprosthetic valves between July 2020 and June 2022. Sixty-two (52.5%) patients, which is a fairly high number of patients, underwent cardiac computed tomography and transthoracic echocardiography one week after surgery. Patients were divided into two groups, those with HALT (n = 14) and those without HALT (n = 48). RESULTS: Of the 62 patients who underwent cardiac computed tomography, HALT was observed in 14 (22.5%) patients during the very early postoperative phase. Reduced leaflet motion was observed in two of the 14 patients. The low-attenuation areas were located outside the prosthetic valve in 10 cases (71.4%) in the HALT group and in 14 cases (29.2%) in the non-HALT group. More than 50% of patients (57.1%) with HALT and 79.2% without HALT were administered warfarin. Neither in-hospital deaths nor postoperative thromboembolic events were observed during hospitalization. No patient had a mean pressure gradient > 20 mmHg in either group. CONCLUSION: HALT was observed in one-fifth of the cases after surgical aortic valve replacement during the very early postoperative phase in an institution wherein administration of continuous heparin infusion after surgery is a standard practice. HALT did not affect the early prognosis or incidence of cerebral infarction.

Preoperative management using Impella support for acute aortic dissection with left coronary malperfusion: a case report.

BACKGROUND: Acute aortic dissection (AAD) with impaired perfusion of the left coronary artery has a poor prognosis, even after urgent radical aortic surgery, due to extensive myocardial damage. Although Impella, a microaxial-flow catheter pump, is useful in managing acute myocardial infarction, it is generally contraindicated in patients with AAD because it is an intra-aortic device and the aortic structure is compromised in these cases. Here, we introduce a novel intervention that allowed a planned aortic repair after managing circulation using Impella and venoarterial extracorporeal membrane oxygenation in a case of AAD with left main trunk malperfusion. CASE PRESENTATION: A 40-year-old man presented with cardiogenic shock. Percutaneous coronary intervention was performed to address left main trunk obstruction using an intra-aortic balloon pump; however, circulatory instability persisted. The patient was transferred to our hospital after venoarterial extracorporeal membrane oxygenation. Impella CP™ was used to improve his circulatory status. However, a subsequent CT scan confirmed an AAD diagnosis. After 5 days of stable circulatory support, the patient underwent aortic root replacement and coronary artery bypass grafting. CONCLUSIONS: In patients with AAD and coronary malperfusion, adjunctive circulatory management with Impella may be a valuable therapeutic option.

Enzyme immobilization on α-1,3-glucan: development of flow reactor with fusion protein of α-1,3-glucan binding domains and histamine dehydrogenase.

α-1,3-Glucanase Agl-KA from Bacillus circulans KA-304 consists of a discoidin domain (DS1), a carbohydrate binding module family 6 (CBM6), a threonine-proline-rich-linker (TP linker), a discoidin domain (DS2), an uncharacterized domain, and a catalytic domain. The binding of DS1, CBM6, and DS2 to α-1,3-glucan can be improved in the presence of two of these three domains. In this study, DS1, CBM6, and TP linker were genetically fused to histamine dehydrogenase (HmDH) from Nocardioides simplex NBRC 12069. The fusion enzyme, AGBDs-HmDH, was expressed in Escherichia coli Rosetta 2 (DE3) and purified from the cell-free extract. AGBDs-HmDH bound to 1% micro-particle of α-1,3-glucan (diameter: less than 1 µm) and 7.5% coarse-particle of α-1,3-glucan (less than 200 µm) at about 97 % and 70% of the initial amounts of the enzyme, respectively. A reactor for flow injection analysis filled with AGBDs-HmDH immobilized on the coarse-particle of α-1,3-glucan was successfully applied to determine histamine. A linear calibration curve was observed in the range for about 0.1 to 3.0 mM histamine. These findings suggest that the combination of α-1,3-glucan and α-1,3-glucan binding domains is a candidate for novel enzyme immobilization.

Large Thrombus Entrapped in a Patent Foramen Ovale during Inferior Vena Cava Filter Protection for Venous Thromboembolism.

Background. A large thrombus entrapped in the patent foramen ovale (PFO) is an extremely rare condition. Moreover, it is considered even rarer after temporary inferior vena cava filter (TIVCF) placement for the prevention of fatal pulmonary embolism due to venous thromboembolism (VTE). Case Report. A 58-year-old man presented with syncope following chest pain and dyspnea due to PE exacerbation during TIVCF protection, which then led to cardiogenic shock. Echocardiography revealed a large thrombus entrapped in the PFO, and computed tomography (CT) showed a bilateral pulmonary artery embolism. The patient was treated with open surgical embolectomy for a pulmonary artery thrombus and PFO thrombus with simultaneous closure of the PFO. The patient's postoperative course was uneventful. Results and Conclusion. Surgical embolectomy was useful with respect to the feasibility of resection of both intracardiac thrombus and pulmonary artery thrombus performed simultaneously, contributing to the prevention of systemic embolisms, and echocardiography plays an important role for early diagnosis.

Review of Implantable Left Ventricular Assist Devices.

Mechanical circulatory support has been an indispensable treatment for severe heart failure. While the development of a total artificial heart has failed, left ventricular assist devices (LVAD) have evolved from extracorporeal to implantable types. The first generation implantable LVAD (pulsatile device) was used as a bridge to transplantation, and demonstrated improvement in survival rate and activity of daily living. The evolution from the first-generation (pulsatile device) to the second-generation (continuous flow device: axial flow pump and centrifugal pump) has resulted in many clinical benefits by reducing mechanical failures and minimizing device size. Furthermore, third-generation devices, which use a moving impeller suspended by magnetic and/or hydrodynamic forces, have improved overall device reliability and durability. Unfortunately, there are still many device-related complications, and further device development and improvement of patient management methods are required. However, we expect to see further development of implantable VADs, including for destination therapy, in future.

[Result of Surgical Treatment for Active Infective Endocarditis at the Aortic Position].

Herein, we retrospectively review our experience with surgical treatment of active aortic valve infective endocarditis, particularly aortic annular abscess, and central nervous system complications. From 2012 to 2021, 46 consecutive patients underwent surgery during the active phase of infective endocarditis, 25 of which were performed at the aortic position. One patient died early (<30 days) due to low output syndrome and another 2 patients who were never discharged died because of general prostration. The actuarial survival rate was 84% at 1 year, and 80% at 3 and 5 years. Eleven patients [6 native valve endocarditis (NVE), 5 prosthetic valve endocarditis (PVE)] had valve annular abscess requiring removal of the infected tissue and reconstruction of a definite anatomic continuity, and aortic valve replacement was subsequently performed in 7 patients and aortic root replacement in 4 patients. Direct closure was performed in 4 patients with partial annulus defects, and reconstruction with an autologous nor bovine pericardium patch was performed in 6 patients with large annulus defects. Preoperative imaging revealed acute cerebral embolism in 10 patients. In eight cases, surgery was performed within 7 days after diagnosis of cerebral embolism. No patient had abnormal postoperative neurological findings. There were no reoperations and no recurrence of infective endocarditis.

Characterization of three γ-glutamyltranspeptidases from Pseudomonas aeruginosa PAO1.

The Pseudomonas aeruginosa strain, PAO1, has three putative γ-glutamyltranspeptidase (GGT) genes: ggtI, ggtII, and ggtIII. In this study, the expression of each of these genes in P. aeruginosa PAO1 was analyzed, and the properties of the corresponding GGT proteins were investigated. This is the first report on biochemical characterization of GGT paralogs from Pseudomonas species. The crude extracts prepared from P. aeruginosa PAO1 exhibited hydrolysis and transpeptidation activities of 17.3 and 65.0 mU/mg, respectively, and the transcription of each gene to mRNA was confirmed by RT-PCR. All genes were cloned, and the expression plasmids constructed were introduced into an Escherichia coli expression system. Enzyme activity of the expressed protein of ggtI (PaGGTI) was not detected in the system, while the enzyme activities of the expressed proteins derived from ggtII and ggtIII (PaGGTII and PaGGTIII, respectively) were detected. However, the enzyme activity of PaGGTII was very low and easily decreased. PaGGTII with C-terminal his-tag (PaGGTII25aa) showed increased activity and stability, and the purified enzyme consisted of a large subunit of 40 kDa and a small subunit of 28 kDa. PaGGTIII consisted of a large subunit of 37 kDa and a small subunit of 24 kDa. The maximum hydrolysis and transpeptidation activities of PaGGTII25aa were obtained at 40ºC-50ºC, and the maximum hydrolysis and transpeptidation activities of PaGGTIII were obtained at 50ºC-60ºC. These enzymes retained approximately 80% of their hydrolysis and transpeptidation activities after incubation at 50ºC for 10 min, reflecting good stability. Both PaGGTII25aa and PaGGTIII showed higher activities of hydrolysis and transpeptidation in the alkali range than in the acidic range. However, they were highly stable at a wide pH range (5-10.5).

ECPELLA as the bridge to surgery in patients with cardiogenic shock due to post-infarct papillary muscle rupture: management of mechanical circulatory support during operation.

Papillary muscle rupture is a fatal complication with a high operative mortality. Most patients experience cardiogenic shock and hypoxia due to pulmonary edema caused by severe mitral regurgitation. Although preoperative stabilization using a mechanical assist device potentially improves surgical outcomes, an appropriate strategy has not yet been established. ECPELLA, combining venoarterial extracorporeal membrane oxygenation and Impella, has the potential to stabilize preoperative status and improve outcome in patients with refractory cardiogenic shock due to papillary muscle rupture. Herein, we present 3 cases involving the efficacy of ECPELLA and our tips of surgical and ECPELLA management in patients with papillary muscle rupture.

A Case of Andexanet Alfa Induced Heparin Resistance in Emergent Aortic Surgery: Successful Anticoagulation Management Using Antithrombin Administration.

Andexanet alfa (AnAl) is utilized for the urgent reversal of direct oral anticoagulants (DOACs) in cases of severe bleeding. While the guidelines from the Society of Thoracic Surgeons recommend AnAl for urgent cardiac surgery in patients treated with DOACs, concerns persist regarding the potential of AnAl to induce heparin resistance. This report details the case of an 85-year-old woman diagnosed with acute type A aortic dissection, who received AnAl due to prior edoxaban use. During the emergent aortic surgery, she exhibited heparin resistance following the administration of unfractionated heparin (UFH). The administration of antithrombin III (ATIII) significantly influenced activated clotting times, facilitating successful surgery while maintaining adequate anticoagulation. This case underscores the importance of cautious management of AnAl-induced heparin resistance during critical surgeries, emphasizing the role of ATIII supplementation for effective anticoagulation.

Right-parasternal approach for aortic valve replacement and ascending aortic repair after ante-thoracic route gastric tube reconstruction.

Due to the limitations of surgical incisions and approaches brought on by the presence of gastric tube (GT), open heart surgery following ante-thoracic route GT reconstruction remains challenging. A-73-year-old man, who had a history of esophageal resection and ante-thoracic route GT reconstruction required aortic valve replacement (AVR) concomitant with ascending aortic repair (AAR) for aortic stenosis and dilated ascending aorta. We performed open heart surgery via a right-parasternal approach to avoid injury to the GT and nutrient arteries. This approach provided a good operative field, similar to median sternotomy. To our knowledge, this is the first case of AVR concomitant with AAR after ante-thoracic route GT reconstruction via a right-parasternal approach. We consider that the right-parasternal approach is reasonable for patients with ante-thoracic route GT reconstruction.

Hypo-attenuated leaflet thickening after Perceval sutureless bioprosthesis implantation.

Modern multi-slice computed tomography (CT) has increased the detection of hypo-attenuated leaflet thickening (HALT). Furthermore, HALT's impact on transcatheter or surgical biological aortic valve (AV) prostheses has attracted attention. However, few reports on HALT in sutureless bioprostheses exist. Herein, we report a case of early structural valve deterioration due to HALT after AV replacement (AVR) with a Perceval bioprosthesis, which improved after anticoagulation therapy. A 79-year-old man admitted to our hospital with paroxysmal atrial fibrillation (PAF) during hemodialysis was also diagnosed with AV stenosis and, coronary artery disease, and PAF. He underwent AVR, coronary artery bypass grafting, and left atrial appendage resection. Although the postoperative course was uneventful with dual antiplatelet therapy, postoperative enhanced CT revealed HALT with reduced leaflet motion, and echocardiography showed an increased transvalvular pressure gradient. After using warfarin with target prothrombin time-international normalized ratio of 2-2.5 and/or heparin with target activated partial thromboplastin time of 45-60 s, the HALT disappeared with an improved transvalvular pressure gradient without any thromboembolic events.

Anterior Papillary Muscle Rupture due to Acute Myocardial Microinfarction of the Small High Lateral Branch.

Papillary muscle rupture is a catastrophic condition, of which most cases manifest posterior papillary muscle rupture. Anterior papillary muscle rupture is a rare condition. Particularly, anterior papillary muscle rupture due to acute myocardial microinfarction of the small high lateral branch is extremely rare. Since papillary muscle rupture can occur even in such a small branch or small area due to myocardial infarction, echocardiographic and/or ventriculographic confirmation is essential in cases of sudden worsening of heart failure. Herein, we report the case of anterior papillary muscle rupture with a good outcome. A 61-year-old man was admitted to our hospital with cardiogenic shock. Echocardiography revealed severe mitral regurgitation due to papillary muscle rupture. Coronary angiography demonstrated high-grade stenosis in the high lateral branch. However, no other significant stenoses were found. Emergency mitral valve replacement was performed. The patient was discharged 19 days after surgery without any complications.

Hemodynamic and clinical performance of the 25-mm Medtronic Mosaic porcine bioprosthesis in the mitral position.

The 25-mm Medtronic Mosaic porcine bioprosthesis (MB25) is the smallest bioprosthesis that has been approved for use in the mitral position in Japan. Various studies have reported satisfactory hemodynamic performance and good long-term outcomes of the Medtronic Mosaic porcine bioprosthesis. However, the hemodynamic and clinical performances of the MB25 in the mitral position remain unknown. This study aimed to evaluate the hemodynamic and clinical performance of the MB25 in mitral valve replacement (MVR). Twenty patients who underwent MVR using the MB25 between February 2013 and April 2018 were studied. We evaluated the hemodynamic performance of the MB25, cardiac chamber size, cardiac function, and systolic pulmonary artery pressure (PAP) using echocardiography during follow-up. The study outcomes were major adverse cardiac events (MACEs) and all-cause mortality. Sixteen patients (80%) had a patient prosthesis mismatch defined as an index effective orifice area of ≤ 1.2 cm2/m2. The left atrial dimension was significantly reduced after surgery (p = 0.0282). The mean pressure gradients (MPG) in the mitral position were 5.5 ± 1.7 mmHg at discharge and 4.2 ± 1.3 mmHg at 1 year postoperatively. The MPG in the mitral position significantly decreased during the follow-up period (p = 0.0489). Systolic PAP significantly improved postoperatively. The 1-, 3-, and 5-year survival rates were 87, 79, and 70%, respectively. No cardiac death occurred. There were no MACEs or reports of structural valve degeneration during the follow-up period. The hemodynamic and clinical performances of the MB25 in the mitral position were satisfactory as the smallest biological mitral valve. The MB25 is a reasonable option for MVR to reduce the surgical difficulty in high-risk patients with an advanced age, a small body size or MAC and when recurrent MVR or complex procedures are performed.

Identification, characterization, and cloning of a novel aminoacylase, L-pipecolic acid acylase from Pseudomonas species.

L-Pipecolic acid is utilized as a vital component of specific chemical compounds, such as immunosuppressive drugs, anticancer reagents, and anesthetic reagents. We isolated and characterized a novel L-aminoacylase, N-acetyl-L-pipecolic acid-specific aminoacylase (LpipACY), from Pseudomonas sp. AK2. The subunit molecular mass of LpipACY was 45 kDa and was assumed to be a homooctamer in solution. The enzyme exhibited high substrate specificity toward N-acetyl-L-pipecolic acid and a high activity for N-acetyl-L-pipecolic acid and N-acetyl-L-proline. This enzyme was stable at a high temperature (60°C for 10 min) and under an alkaline pH (6.0-11.5). The N-terminal and internal amino acid sequences of the purified enzyme were STTANTLILRNG and IMASGGV, respectively. These sequences are highly consistent with those of uncharacterized proteins from Pseudomonas species, such as amidohydrolase and peptidase. We also cloned and overexpressed the gene coding LpipACY in Escherichia coli. Moreover, the recombinant LpipACY exhibited properties similar to native enzyme. Our results suggest that LpipACY is a potential enzyme for the enzymatic synthesis of L-pipecolic acid. This study provides the first description of the enzymatic characterization of L-pipecolic acid specific amino acid acylase.