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.

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.

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.

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.

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.

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).

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.

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.

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.

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.

[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.

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.

Analysis of microRNAs by the Stem-Loop Real-Time Quantitative Reverse Transcription Polymerase Chain Reaction Using A Double Quencher Probe

Introduction/Objective

We created a universal probe that can be used with mature micro RNAs (miRNAs) using a double quencher incorporating the ZEN quencher into the hydrolysis probe required for miRNA analysis by the real- time quantitative polymerase chain reaction (RT-qPCR) using a stem-loop primer. The main purpose of this approach was to improve sensitivity and convenience.

Methods/Case Report

We conducted studies on miR-21, miR-30a and miR-200c. To assess the relationship between the sequence interval and reactivity between the miRNA-specific sequence on the stem-loop primer and detection probe, various sequence patterns were examined using miRNA from K562 cells. The sensitivity and reactivity of the designed primers and probes were examined using each synthetic miRNA and transurethral resection of bladder tumor (TURBT) samples. The synthetic RNA was serially diluted in 10% increments. Twenty-seven TURBT cases were examined. The prepared samples were extracted with the FastGene RNA Basic Kit and FastGene miRNA Enhancer. After extraction, cDNA was prepared using FastGene Scriptase II. We performed quantitative analysis by the RT-qPCR using a ZEN double quencher probe. The samples were analyzed with the Taq Man miRNA assay.

Results (if a Case Study enter NA)

The probe and miRNA-specific sequences of the stem-loop primer showed better reactivity when the design contained less space within the sequences. Serial dilution of the samples using synthetic miRNA showed that linearity depended on the addition amount, and occurred at a concentration of log 7 or more. In the TURBT samples, the Δ of the mean Cp value, and the correlation coefficients of miR-21, miR-30a, and miR-200c, were 3.13 and 0.966; 1.10 and 0.991; and 0.39 and 0.997, respectively, compared with the TaqMan miRNA assay.

Conclusion

This demonstrates that our method has the same or higher sensitivity than the TaqMan miRNA assay. Overall, these findings suggest that the analysis of miRNA with a stem-loop primer using the double quencher probe is useful.

Characterization of lipidic plaque materials at calcified atheroma: its association with calcification thickness evaluated by optical coherence tomography and near-infrared spectroscopy imaging

Introduction

The degree of calcification and its thickness have been considered to affect stent expansion, leading to an increases risk of repeat revascularization in patients receiving PCI. Pathophysiologically, accumulation of lipidic materials within vessel wall could trigger the formation of plaque calcification. Elucidating characteristics of lipidic plaque components at calcified atheroma may enable to identify phenotypes with thick calcification which less likely responds to PCI.

Purpose

This study investigated the relationship of calcification thickness with lipidic plaque materials at calcified atheroma by using OCT and near-infrared spectroscopy (NIRS) imaging.

Methods

We analyzed 52 calcified lesions (culprit/non culprit lesions=44/8) in 47 CAD patients (stable CAD/ACS=36/11) from the REASSURE-NIRS registry (NCT04864171). OCT and NIRS imaging evaluated 4-mm segment exhibiting maximum superficial calcification arc. Calcification thickness on OCT imaging, its arc on IVUS imaging, and NIRS-derived lipid arc were analyzed at every 1-mm interval cross-sectional images. In addition, yellow-calcification ratio (YCR = lipid arc/calcification arc) was calculated (Figure 1).

Results

53% of study subjects exhibited chronic kidney disease and 70% of them received a statin (averaged on-treatment LDL-C =89mg/dL). Throughout OCT and NIRS/IVUS imaging analysis of 260 cross-sectional images, the averaged calcification arc, its maximum thickness, lipid arc and YCR were 210° (167–285°), 0.78mm (0.62–0.95mm), 95° (31–169°) and 0.33 (0.09–0.59), respectively. As expected, thicker calcification more likely exhibited a greater calcification arc (r=0.30, p&lt;0.001). Furthermore, a greater thickness of calcification was associated with smaller lipidic plaque burden, reflected by yellow arc (r=−0.36, p&lt;0.001) and YCR (r=−0.36, p&lt;0.001) (Figure 2). After adjusting age, gender and ACS, calcification arc (p&lt;0.001) and YCR (p&lt;0.001) continued to predict thicker calcification.

Conclusion

Thickening of calcification was associated with severer calcification arc, which was accompanied by the shrinkage of lipidic plaques. Our findings suggest the evaluation of lipidic plaque component as a potential tool to identify calcified atheroma harbouring thick calcification, which may cause a greater risk of stent underexpansion.

Funding Acknowledgement

Type of funding sources: None.

Deterioration of cardiogenic shock after acute myocardial infarction defined by the society for cardiovascular angiography and intervention cardiogenic shock classification scheme

Background

Cardiogenic shock (CS) in patients with AMI presents worse cardiovascular outcomes, which suggests the need for better risk stratification and management. The Society for Cardiovascular Angiography and Intervention (SCAI) has recently proposed CS classification scheme, which stratifies CS into 5 groups according to hypotension and hypoperfusion. While stage A and B exhibits CS without hypotension and/or hypoperfusion, their clinical condition could rapidly deteriorate into stage C-E. However, clinical characteristics and in-hospital outcomes of CS exhibiting its deterioration remains uncertain.

Purpose

To characterize AMI patients who deteriorated their CS status from stage A and B into stage C-E.

Methods

This single-center observational study included 326 consecutive AMI patients receiving primary PCI who presented CS stage A and B on arrival (2019.09.01–2021.09.30). Deterioration of CS (D-CS) was defined as the progression from stage A and B on arrival to stage C-E after primary PCI. Clinical characteristics and outcomes were compared in those with and without D-CS.

Results

D-CS was identified in 16.0% of entire subjects (=52/326). Of these, 94.2 and 5.8% of them exhibited stage C and E, respectively (Figure). Patients with D-CS more likely presented STEMI (84.6 vs. 67.9%, p=0.01) with a lower systolic BP (sBP) level (130±31 vs. 148±26mmHg, p&lt;0.001) and a reduced LVEF (43±13 vs. 51±9%, p&lt;0.001), whereas there was no significant difference in lactate level (1.5±0.4 vs. 1.2±0.3 mmol/L, p=0.22). Pre-TIMI flow grade 0–1 (69.2 vs. 47.8%, p=0.006), left main trunk stenosis (9.6 vs. 1.5%, p=0.007) and chronic total occlusion (21.2 vs. 8.4%, p=0.01) were more frequently observed in those with D-CS. Despite achieving a shorter onset-to-reperfusion time (199 vs. 276 minutes, p=0.002), D-CS was associated with in-hospital all-cause mortality after adjusting clinical characteristics (HR=33.6, 95% CI: 2.2–502.0, p=0.01). Furthermore, mechanical circulatory support (MCS) (30.8 vs. 0%, p&lt;0.001) was more frequently required in patients with D-CS (IABP: 28.8 vs. 0%, p&lt;0.001, ECMO: 11.5 vs. 0%, p&lt;0.001, Impella: 3.8 vs. 0%, p=0.02). Further analysis identified sBP (HR=0.98, 95% CI: 0.97–1.00, p=0.008), LVEF (HR=0.94, 95% CI: 0.90–0.97, p&lt;0.001) and pre-TIMI flow grade 0–1 (HR=0.41, 95% CI: 0.19–0.86, p=0.01) as independent contributors to D-CS. ROC analysis demonstrated sBP &lt;135 mmHg (AUC=0.65) and LVEF &lt;50% (AUC=0.69) as best cut-off values to predict D-CS. Of note, a risk of D-CS increased in association with the number of these three factors (p&lt;0.001), and 44.0% of those with all of these factors presented D-CS (Figure).

Conclusion

16.0% of AMI without any hypotension/hypoperfusion on arrival exhibited deterioration of CS status on SCAI classification. The combination of sBP, LVEF and pre-TIMI flow grade could help to identify AMI subjects with a risk of D-CS, who may benefit from early adoption of intensified management including MCS prior to PCI.

Funding Acknowledgement

Type of funding sources: None.

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.

AB0667 EFFECT OF TEMPERATURE VARIATION ON SERUM KL-6 LEVELS IN PATIENTS WITH SYSTEMIC SCLEROSIS

Background

Serum Krebs von den Lungen-6 (KL-6) levels has much evidence as a biomarker about the progression and prognosis of interstitial lung disease (ILD), including systemic sclerosis (SSc)-associated ILD1-4. However, serum KL-6 levels often fluctuate regardless of the progression of ILD. This sometimes mislead the evaluation of the disease activity, however, the reason for the fluctuation has not been clarified.

Objectives

We tested the hypothesis that serum KL-6 levels are affected by ambient temperature in patients with SSc.

Methods

We defined the warm season（May–October）as the period when the ambient temperature was above the Tokyo metropolitan average ambient temperature announced by the Japan Meteorological Agency, and the cold season (November–April）as the period when the ambient temperature was below the average. ILD was classified based on chest CT findings. Among SSc patients who had visited our department since May 2018, we selected those who had data of serum KL-6 levels at least 3 times in warm and cold seasons from October 2014 to September 2021, respectively. Patients having malignancy were excluded after confirmation of the onset of malignancy using medical record retrospectively. The difference in serum KL-6 levels between warm and cold seasons was evaluated by Wilcoxon’s rank-sum test.

Results

In total, 252 patients with SSc were included. Median age was 66.3 years, with median disease duration of 13.5 (8.9–19.2）years, diffuse cutaneous type of 94 (37.3%）patients, and concomitant ILD of 120（47.6%）patients (Table 1). The median follow-up was 6.4 (4.4–6.8）years, with median KL-6 measurement of 24（14–39）times. Serum KL-6 levels were significantly higher in the cold season than that in the warm season, with a greater difference in the group with ILD（536 IU/L vs. 492 IU/L, p = 0.0012 in the group with ILD, 364 IU/L vs. 345 IU/L in the group without ILD, p = 0.0028）.

Table 1.

Patients characteristics

With ILD (n=120)Without ILD (n=132)P valueFemale, n (%)110 (43.7)128 (52.4)0.1Age, years (IQR)65.8(56.1–73.4)66.4(56.0–72.5)0.77Disease duration, years (IQR)14.0 (9.8-21.0)13.0 (8.7-18.0)0.23Modified Rodnan skin score (IQR)10 (4-15)6 (2-11)0.0017Diffuse SSc, n (%)53 (40.2)27 (20.5)<0.001Pulmonary hypertension, n (%)4 (3.3)3 (2.3)0.71ANA positive, n (%)98 (81.7)112 (84.8)0.50SSc-related autoantibody, n (%)98 (81.7)112 (84.8)0.50Anti-centromere antibody, n (%)17 (14.2)86 (71.7)<0.0001Anti-topoisomeraseⅠ antibody, n (%)63 (52.5)8 (6.1)<0.0001Anti-RNA polymerase Ⅲ antibody, n (%)7 (5.8)11 (8.3)0.62Anti-U1-RNP antibody, n (%)15 (12.5)13 (9.8)0.54KL-6, IU/L (IQR)548 (384–876.8)233 (191.3–302)<0.0001KL-6 measurement, times (IQR)33.5(20-45)18.5(12.3-28)<0.0001Steroid use, n (%)68 (56.7)22 (16.7)<0.0001Cyclophosphamide, n (%)44 (36.7)12 (9.1)<0.0001Other Immunosuppressive agents, n (%)31 (25.8)0.002

Conclusion

Our results suggest that cold ambient temperature may affect serum KL-6 levels in patients with SSc.

References

[1]Distler O, et al. Eur Respir J.2020;55:1902026.

[2]Kuwana M et al. J Rheumatol 2016;43:1825-31

[3]Volkmann et al. Arthritis Rheumatol.2019;71:2059-2067

[4]Elhai M et al. Arthritis Rheumatol. 2019;71:972-982.

Figure 1.

Disclosure of Interests

Hikaru Hirose Grant/research support from: Bayer Yakuhin, Ltd, Tomoaki Higuchi: None declared, Kae Takagi: None declared, Akiko Tochimoto: None declared, Yasushi Kawaguchi: None declared, Masayoshi Harigai Speakers bureau: AbbVie Japan, Ayumi, Boehringer Ingelheim Japan, Bristol-Myers Squibb, Chugai, Eisai, Eli Lilly Japan, GlaxoSmithKline, Kissei, Pfizer Japan Inc, Takeda, Teijin, Consultant of: AbbVie Japan, Boehringer Ingelheim Japan, Bristol-Myers Squibb, Kissei, Teijin, Grant/research support from: AbbVie Japan, Asahi Kasei, Astellas, Ayumi, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Kissei, Mitsubishi Tanabe, Nippon Kayaku, Sekisui Medical, Shionogi, Taisho, Takeda, Teijin

OP0112 THE EVER-LARGEST ASIAN GWAS FOR SYSTEMIC SCLEROSIS AND TRANS-POPULATION META-ANALYSIS IDENTIFIED SEVEN NOVEL LOCI AND A CANDIDATE CAUSAL SNP IN A CIS-REGULATORY ELEMENT OF THE FCGR REGION

Background

Genome-wide association studies (GWASs) have identified 29 disease-associated single nucleotide polymorphisms (SNPs) for systemic sclerosis (SSc) in non-human leukocyte antigen (HLA) regions (1-7). While these GWASs have clarified genetic architectures of SSc, study subjects were mainly Caucasians limiting application of the findings to Asians.

Objectives

The study was conducted to identify novel causal variants for SSc specific to Japanese subjects as well as those shared with European population. We also aimed to clarify mechanistic effects of the variants on pathogenesis of SSc.

Methods

A total of 114,108 subjects comprising 1,499 cases and 112,609 controls were enrolled in the two-staged study leading to the ever-largest Asian GWAS for SSc. After applying a strict quality control both for genotype and samples, imputation was conducted using the reference panel of the phase 3v5 1,000 genome project data combined with a high-depth whole-genome sequence data of 3,256 Japanese subjects. We conducted logistic regression analyses and also combined the Japanese GWAS results with those of Europeans (6) by an inverse-variance fixed-effect model. Polygenicity and enrichment of functional annotations were evaluated by linkage disequilibrium score regression (LDSC), Haploreg and IMPACT programs. We also constructed polygenic risk score (PRS) to predict SSc development.

Results

We identified three (FCRLA-FCGR, TNFAIP3, PLD4) and four (EOMES, ESR1, SLC12A5, TPI1P2) novel loci in Japanese GWAS and a trans-population meta-analysis, respectively. One of Japanese novel risk SNPs, rs6697139, located within FCGR gene clusters had a strong effect size (OR 2.05, P=4.9×10-11). We also found the complete LD variant, rs10917688, was positioned in cis-regulatory element and binding motif for an immunomodulatory transcription factor IRF8 in B cells, another genome-wide significant locus in our trans-ethnic meta-analysis and the previous European GWAS. Notably, the association of risk allele of rs10917688 was significant only in the presence of the risk allele of the IRF8. Intriguingly, rs10917688 was annotated as one enhancer-related histone marks, H3K4me1, in B cells, implying that FCGR gene(s) in B cells may play an important role in the pathogenesis of SSc. Furhtermore, significant heritability enrichment of active histone marks and a transcription factor C-Myc were found in B cells both in European and Japanese populations by LDSC and IMPACT, highlighting a possibility of a shared disease mechanism where abnormal B-cell activation may be one of the key drivers for the disease development. Finally, PRS using effects sizes of European GWAS moderately fit in the development of Japanese SSc (AUC 0.593), paving a path to personalized medicine for SSc.

Conclusion

Our study identified seven novel susceptibility loci in SSc. Downstream analyses highlighted a novel disease mechanism of SSc where an interactive role of FCGR gene(s) and IRF8 may accelerate the disease development and B cells may play a key role on the pathogenesis of SSc.

References

[1]F. C. Arnett et al. Ann Rheum Dis, 2010.

[2]T. R. Radstake et al. Nat Genet, 2010.

[3]Y. Allanore et al. PLoS Genet, 2011.

[4]O. Gorlova et al. PLoS Genet, 2011.

[5]C. Terao et al. Ann Rheum Dis, 2017.

[6]E. López-Isac et al. Nat Commun, 2019.

[7]W. Pu et al. J Invest Dermatol, 2021.

Disclosure of Interests

None declared

Pathophysiological Analysis of Uninephrectomized db/db Mice as a Model of Severe Diabetic Kidney Disease

Diabetic nephropathy, included in diabetic kidney disease (DKD), is the primary disease leading to end-stage renal disease (ESRD) or dialysis treatment, accounting for more than 40% of all patients with ESRD or receiving dialysis. Developing new therapeutics to prevent the transition to ESRD or dialysis treatment requires an understanding of the pathophysiology of DKD and an appropriate animal model for drug efficacy studies. In this study, we investigated the pathophysiology of diabetic kidney disease with type 2 diabetes in uninephrectomized db/db mice. In addition, the nephrectomized db/db mice from 10 weeks to 42 weeks were used to assess the efficacy of long-term administration of the angiotensin-II–receptor antagonist losartan. The blood and urinary biochemical parameters and the blood pressure which is a main pharmacological endpoint of the losartan therapy, were periodically measured. And at the end, histopathological analysis was performed. Uninephrectomized db/db mice clearly developed obesity and hyperglycemia from young age. Furthermore, they showed renal pathophysiological changes, such as increased urinary albumin-creatinine ratio (UACR) (the peak value 3104±986 in 40-week-old mice), glomerular hypertrophy and increased fibrotic areas in the tubulointerstitial tubules. The blood pressure in the losartan group was significantly low compared to the normotensive Vehicle group. However, as expected, Losartan suppressed the increase in UACR (829±500) indicating the medication was sufficient, but the histopathological abnormalities including tubular interstitial fibrosis did not improve. These results suggest that the uninephrectomized db/db mice are useful as an animal model of the severe DKD indicated by the comparison of the efficacy of losartan in this model with the efficacy of losartan in clinical practice.

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.

Substantially elevated thromboembolic and bleeding risks in patients with AMI following acute/subacute stroke events

Introduction

AMI infrequently but concomitantly occurs after stroke events. Current guideline recommends primary PCI with DAPT in the setting of AMI. However, this approach is not necessarily applicable in AMI subjects following acute/subacute stroke events due to its bleeding risk. Clinical management and outcomes of these AMI subjects following remains uncertain.

Purpose

To characterize management and clinical outcomes in patients with AMI following acute/subacute stroke events (=post-stroke AMI).

Methods

The current study retrospectively analyzed 2041 AMI patients hospitalized at our institute from 2007 to 2018. Post-stroke AMI was defined as its occurrence within 14 days after ischemic/hemorrhagic stroke. The use of reperfusion and anti-thrombotic therapies, and the occurrence of major adverse cardiovascular events (=CV death, non-fatal MI and non-fatal stroke) and major bleeding events (BARC type 3 or 5) were compared in post-stroke and non-post-stroke AMI patients.

Results

Post-stroke AMI was identified in 1.1% of entire subjects (=23/2041). Of these, 65% of them (=15/23) had AMI within 3 days from the onset of stoke event. Over 60% of them was due to cardioembolic stroke, followed by hemorrhagic (9%), atherothrombotic ones (8%) and other causes (22%). Post-stroke AMI patients were more likely to exhibit Af (p=0.02) and a history of hemodialysis (p=0.009), and have a lower BMI (p=0.04) and hemoglobin level (p=0.02). They were less likely to receive emergent coronary angiography, and primary PCI was conducted in only 65% of post-stroke AMI patients (Table). Furthermore, they more frequently received thrombectomy (p=0.04) alone rather than stent implantation (p=0.002) (Table). With regard to anti-thrombotic therapy, the proportion of DAPT use was significantly lower in post-stroke AMI subjects (52 vs. 89%, p=0.0001), and 17% of them did not receive any anti-thrombotic agents. Of note, only 48% (p=0.04) and 43% (p=0.0001) of post-stroke AMI patients were treated with other established medical therapies including β-blocker and statin, respectively. During the observational period (median = 2.9 years), post-stroke AMI was associated with a greater likelihood experiencing major adverse cardiovascular events (log-rank p&lt;0.001, Figure), CV death (log-rank p&lt;0.0001) and stroke events (log-rank p&lt;0.0001). Furthermore, the frequency of their major bleeding events was substantially elevated (log-rank p&lt;0.001, Figure).

Conclusions

In our real-world data, the adoption of guideline-recommended reperfusion and anti-thrombotic therapies were considerably low in AMI subjects following acute/subacute stroke events. Given their elevated risk of cardiovascular and bleeding events, it is required to establish better therapeutic management for mitigating their thrombotic/bleeding risks.

Funding Acknowledgement

Type of funding sources: None. Table 1Figure 1

The relationship of the underlying lipidic plaque at the implanted newer-generation drug-eluting stents with future stent-related events: insights from the REASSURE-NIRS registry

Background

Lipid-rich plaque is an important substrate causing acute coronary events. Near-infrared spectroscopy (NIRS) imaging has been shown to visualize lipidic coronary plaque at non-culprit site associated with future coronary events. Given that histopathological studies reported that the unstable plaque underlying the implanted drug-eluting stent (DES) could cause neoatherosclerosis formation, we hypothesized that NIRS-based evaluation of lipidic plaque burden behind the implanted DES may clinically predict the occurrence of stent failure in patients with CAD receiving PCI.

Purpose

We aimed to investigate the relationship of stent-related events' risk with lipidic plaque materials behind the implanted DES imaged by NIRS/intravascular ultrasound (NIRS/IVUS) imaging.

Methods

The REASSURE-NIRS registry is an on-going multi-center registry to enroll CAD subjects receiving NIRS/IVUS-guided PCI. In this registry data, 406 lesions in 379 CAD subjects (ACS/non-ACS=150/229) receiving new-generation DES were analyzed. Minimum stent area (MSA) after PCI and maximum lipid-core-burden index in any 4mm-segment within the implanted stents (in-stent maxLCBI4mm) were measured. A 3-year lesion-oriented composite outcome [LOCO: culprit lesion-related MI + ischemia-driven target lesion revascularization (ID-TLR)] was compared in subjects stratified according to the tertile of in-stent maxLCBI4mm.

Results

The mean value of in-stent maxLCBI4mm was 221, and 17% of lesions exhibited in-stent maxLCBI4mm &gt;400. Patients with a greater in-stent maxLCBI4mm were more likely to exhibit a higher LDL-C level (p=0.026) with a longer stent length (p&lt;0.001) and a smaller MSA (p=0.033) (Picture 1). Over 95% of entire study subjects received a statin. During the observational period (median=726 days), the frequency of LOCO up to 3 years was 3.4% in entire study subjects (culprit lesion-related MI=1.0%, ID-TLR=2.8%). Kaplan-Meier curve analysis demonstrated that the occurrence of LOCO did not increase in association with in-stent maxLCBI4mm (log-rank p-value=0.25, Picture 2). In addition, in-stent maxLCBI4mm did not associate with each component of LOCO (culprit lesion-related MI: p=0.502, ID-TLR: p=0.872). Receiver Operating Characteristic analysis revealed that the predictive ability of in-stent maxLCBI4mm for the occurrence of LOCO was unsatisfactorily (c-statistics=0.486).

Conclusion

The amount of underlying lipidic materials at culprit lesions receiving new-generation DES implantation did not necessarily predict future stent-related events. Clinical significance of maxLCBI4mm behind the implanted DES may be different from that at naïve non-culprit plaques.

Funding Acknowledgement

Type of funding sources: None. Background and lesion characteristicsKaplan-Meier analysis for LOCO

Characterization of residual lipid-rich plaques despite achieving LDL-C &lt;1.8mmol/l with a statin in patients with coronary artery disease: insights from the REASSURE-NIRS registry

Introduction

Recent studies have demonstrated favourable modification of lipidic plaque materials under achieving LDL-C &lt;1.8mmol/l with a statin, which potentially accounts for its clinical benefit. However, coronary events still occur even under optimal LDL-C management. This may suggest the presence of residual lipid-rich coronary plaque despite on-treatment LDL-C &lt;1.8mmol/l. Given that near-infrared spectroscopy (NIRS) enables quantitative evaluation of lipidic plaque in vivo, we employed this imaging modality to investigate characteristics and drivers of residual lipid-rich plaques in statin-treated patients with coronary artery disease (CAD) who achieved LDL-C &lt;1.8mmol/l.

Purpose

To clarify the frequency, clinical demographics and factors associated with residual lipid-rich plaques under LDL-C &lt;1.8mmol/l.

Methods

The REASSURE-NIRS registry is an on-going multi-center registry to enroll CAD subjects receiving NIRS/intravascular ultrasound-guided PCI. The current analysis included 133 statin-treated stable CAD patients with on-treatment LDL-C &lt;1.8mmol/l from August 2015 to December 2020. The maximum 4-mm lipid core burden index (maxLCBI4mm) at culprit lesions was measured by NIRS imaging prior to PCI. Clinical characteristics were compared in patients with and without maxLCBI4mm ≥400 at culprit lesions.

Results

In the current study, 45% (=58/128) of study subjects exhibited maxLCBI4mm ≥400 at culprit lesions under on-treatment LDL-C &lt;1.8 mmol/l. They were more likely to be female, whereas there were no differences in age and the frequency of risk factors. Most of study subjects received moderate to high-intensity statin (p=0.79), and over one-fourth of them were treated with ezetimibe (p=0.56). Under these lipid-lowering therapies, LDL-C level was significantly higher in patients with maxLCBI4mm ≥400 (Table). Additionally, a lower frequency of LDL-C &lt;1.4mmol/l was observed in those exhibiting maxLCBI4mm ≥400 (31.0 vs. 45.7%), but this comparison failed to meet statistical significance (p=0.09). Despite LDL-C control with a statin, deterioration of coronary flow after PCI with stent implantation more frequently occurred in patients with maxLCBI4mm ≥400 (Table). Multivariate analysis demonstrated that an independent factor associated with maxLCBI4mm ≥400 was LDL-C level (OR=1.05; 95% CI=1.00–1.10, p=0.03), but not other lipid and clinical parameters.

Conclusion

Almost half of CAD subjects who achieved LDL-C level &lt;1.8mmol/l still exhibited the accumulation of lipidic plaque materials within vessel wall. Given that LDL-C level was associated with this residual lipid-rich plaque features, our findings support current ESC-guideline recommended LDL-C goal (&lt;1.4mmol/l) to optimize the secondary prevention in stable CAD patients.

Funding Acknowledgement

Type of funding sources: None.

Short-segment coronary artery bypass grafting using radial artery to repair bilateral coronary ostial aneurysms after aortic root replacement in a patient with Marfan syndrome

Coronary ostial aneurysm is a complication of aortic root replacement, particularly in Marfan syndrome. Reconstructing the coronary artery is an important problem during reoperation. Herein, we report a case of coronary artery bypass grafting using radial artery to repair bilateral coronary ostial aneurysms after aortic root replacement in a patient with Marfan syndrome.

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.

l-tryptophan-histidine synthesis by Pseudomonas serine peptidase, an amino acid ester hydrolase of the peptidase family S9

Pseudomonas sp. KM1 produces an amino acid ester hydrolase (KM1AEH) that catalyzes peptide bond formation by acting on carboxylic ester bonds. The KM1AEH gene was cloned from genomic DNA and expressed in Escherichia coli. The recombinant enzyme (rKM1AEH) was purified, and gel filtration showed that it is a 68 kDa monomeric protein. rKM1AEH can synthesize the vasoactive dipeptide tryptophan-histidine from tryptophan methyl ester and histidine as acyl donor and acceptor, respectively. The enzyme showed maximum activity at pH 9.5 and 45 °C and was specifically inhibited by silver (Ag⁺). Mutation of the catalytic Ser459 residue in the active site of rKM1AEH with Ala, Cys, or Thr eliminated all catalytic activity. The enzyme is a novel ester hydrolase that belongs to the peptidase family S9 based on the phylogenetic analysis.

Evaluation of hemodynamics after mitral valve replacement with the St Jude Medical Epic bioprosthesis: a Japanese single-center experience

To assess the early hemodynamics after mitral valve replacement (MVR) using the St Jude Medical (SJM) Epic bioprosthesis. MVR was performed using the SJM Epic bioprosthesis in 35 patients from June 2018 to April 2020; three patients were excluded because the postoperative transthoracic echocardiography (TTE) data were unavailable. Data from postoperative TTE at 1 week and 3 months after the procedure were reviewed. The mean mitral pressure gradient (mMPG) was calculated using a continuous wave Doppler method. Left ventricular outflow tract (LVOT) was calculated using a pulse wave Doppler method. The effective orifice area (EOA) was measured from pressure half time. There were 12 men (37.5%) and 20 women (62.5%) with a mean age of 75.9 years (61-88 years). The mean body surface area was 1.51 ± 0.22 cm². The 25 mm and 27 mm valves were used in more than 50% of cases. The mMPG was 4.9 ± 1.7 mmHg and 5.4 ± 1.6 mmHg at 1 week and 3 months after surgery, respectively. EOA was 2.18 ± 0.50 cm² and 2.31 ± 0.59 cm² at 1 week and 3 months after surgery, respectively. The peak velocity of the LVOT (n = 22) was 103.3 ± 21.3 cm/s and 106.8 ± 27.4 cm/s at 1 week and 3 months after surgery, respectively. No findings suggested paravalvular regurgitation and LVOT obstruction. Using the SJM Epic bioprosthesis in MVR resulted in satisfactory hemodynamics in the early postoperative period, even with small valve sizes. Further accumulation of cases and evidence, including mid- to long-term results, is required in the future.

A lost suture needle in the left ventricle 4 years after cardiac surgery

We present an unusual case of a patient with a lost suture needle in the left ventricle, 4 years after cardiac surgery. We show the temporal image comparison using computed tomography as well as the macro and pathological findings of the suture needle and myocardium.

Impact of the Trifecta bioprosthetic valve in patients with low-flow severe aortic stenosis

Aortic stenosis (AS) is the most common valve disorder in advanced age. Previous reports have shown that low-flow status of the left ventricle is an independent predictor of cardiovascular mortality after surgery. The Trifecta bioprosthesis has recently shown favorable hemodynamic performance. This study aimed to evaluate the effect of the Trifecta bioprosthesis, which has a large effective orifice area, in patients with low-flow severe AS who have a poor prognosis. We retrospectively evaluated 94 consecutive patients with severe AS who underwent aortic valve replacement (AVR). Patients were divided into two groups according to the stroke volume index (SVI): low-flow (LF) group (SVI < 35 ml/m², n = 22) and normal-flow (NF) group (SVI ≥ 35 ml/m², n = 72). Patients’ characteristics and early and mid-term results were compared between the two groups. There were no differences in patients’ characteristics, except for systolic blood pressure (LF:NF = 120:138 mmHg, p < 0.01) and the rate of atrial fibrillation between the groups. A preoperative echocardiogram showed that the pressure gradient was higher in the NF group than in the LF group, but aortic valve area was similar. The Trifecta bioprosthesis size was similar in both groups. The operative outcomes were not different between the groups. Severe patient–prosthesis mismatch (PPM) (< 0.65 cm²/m²) was not observed in either of the groups. There were no significant differences in mid-term results between the two groups. The favorable hemodynamic performance of the Trifecta bioprosthesis appears to have the similar outcomes in the LF and NF groups. AVR with the Trifecta bioprosthesis should be considered for avoidance of PPM, particularly in AS patients with LV dysfunction.

Prevention of postoperative intrapericardial adhesion by dextrin hydrogel

OBJECTIVE

Postoperative intrapericardial adhesion increases the risk of complications in patients undergoing reoperation. We investigated the effect of a bioabsorbable dextrin hydrogel (DHG) on the formation of intrapericardial adhesions.

METHODS

Intrapericardial adhesion was surgically induced in Japanese white rabbits with DHG treatment (Adh + DHG) or without DHG treatment (Adh). The sham group was not treated with DHG and intrapericardial adhesion was not induced. The extent of intrapericardial adhesion was assessed by adhesion scoring and crystal violet staining of the pericardial cavity. Bromodeoxyuridine (BrdU) uptake assay was performed to assess the proliferative response to the injury in the tissue beneath the intrapericardial adhesion.

RESULTS

The Adh + DHG group showed looser intrapericardial adhesions compared to the Adh group. The adhesion area of the Adh + DHG group was 4.6 ± 2.2%, whereas that of the Adh group was 32.6 ± 6.4% at the end of the 28-day observation period (p < 0.01). The induction of intrapericardial adhesion resulted in a proliferative response mainly in the cardiac tissue just beneath the adhesion. There were 48.6 ± 10.7 cells/0.1 mm² BrdU-positive cells in the Adh + DHG group and 135.7 ± 23.8 cells/0.1 mm² BrdU-positive cells in the Adh group on day 28 (p < 0.05).

CONCLUSION

These findings indicate that DHG effectively prevented intrapericardial adhesion in this model.

Minimally invasive cardiac surgery in a patient with osteopetrosis and symptomatic mitral regurgitation

Osteopetrosis is a rare hereditary bone development disorder caused by osteoclast dysfunction, which increases bone density. Although few studies have investigated cardiovascular disease in osteopetrosis, sternotomy outcomes in this condition are unclear. We report the case of a patient with osteopetrosis and severe mitral regurgitation. A 63-year-old woman with exertional dyspnea had regurgitant systolic murmur audible at the apex. Transthoracic echocardiography showed severe mitral regurgitation due to posterior leaflet prolapse on the anterolateral side. Radiological findings revealed increased bone density (consistent with osteopetrosis). Considering risks in median sternotomy, we performed minimally invasive cardiac surgery through right minithoracotomy for mitral regurgitation. Preoperative imaging showed sclerotic rib changes; nevertheless, sufficient surgical views obtained involved the intercostal space. No residual mitral regurgitation was observed, and the postoperative course was good. To the best of our knowledge, this is the first case report on minimally invasive cardiac surgery for mitral regurgitation with osteopetrosis.

Catheter ablation of atrial fibrillation benefits the patients with heart failure and preserved ejection fraction as well as those with heart failure and reduced ejection fraction

Background

Although catheter ablation of atrial fibrillation (AF) has recently been shown to improve the cardiac function and even mortality in patients with heart failure (HF) and reduced ejection fraction (HFrEF), few studies have examined the outcomes of AF catheter ablation in patients with HF with preserved ejection fraction (HFpEF).

Purpose

To verify the impact of AF catheter ablation on the cardiac function and HF status in patients with HFpEF.

Methods

We studied 306 patients with HF who had a history of an HF hospitalization and/or preprocedural serum BNP levels &gt;100pg/ml (age, 68.9±8.2 years old; male, 66.3%; non-paroxysmal AF, 63.1%, left atrial diameter [LAD], 42.5±6.3 mm; left ventricular ejection fraction [LVEF], 60.6±12.0%) out of 596 consecutive patients who underwent pulmonary vein isolation-based catheter ablation of AF. The patients with an LVEF ≥50% were defined as having HFpEF (n=262; age, 69.0±8.2 years old; male, 64.5%; non-paroxysmal AF, 61.8%, LAD, 42.1±5.9 mm; left LVEF, 64.0±8.2%) and the remaining patients with an LVEF &lt;50% were defined as having HFrEF (n=44, age, 67.9±8.7 years old; male, 77.0%; non-paroxysmal AF, 70.5%, LAD, 44.9±8.2 mm; LVEF, 40.1±10.2%). The patients received periodic follow-ups for 12 months after the catheter ablation. The cardiac function parameters including the echocardiographic findings and HF functional status of the patients were compared between baseline and 12 months, stratified by the HF subgroup.

Results

AF recurred in 60 patients with HFpEF (22.9%) and in 14 with HFrEF (31.8%) during the 12 month follow-up (p=0.27), however, sinus rhythm was maintained at 12 months in most of the patients (253 patients with HFpEF [96.6%] and 42 patients with HFrEF [95.5%]) (p=0.71). Figure 1 compares the changes in the cardiac function parameters and NYHA functional class from baseline to the 12-month follow-up stratified by the HF subgroup. Both the patients with HFpEF and HFrEF had significant improvements in the serum BNP levels, chest thorax ratio, and LVEF determined by echocardiography. LA reverse remodeling as shown by a significant reduction in the LAD was observed in both HF subgroups, however, the E/E', an index of the LV diastolic function, did not significantly change in either of the subgroups. Similar to the patients with HFrEF, an improvement in the NYHA functional class was seen in those with HFpEF.

Conclusions

Catheter ablation of AF may benefit patients with HFpEF as well as those with HFrEF. Sinus rhythm maintenance achieved by AF catheter ablation in patients with HFpEF may lead to LA reverse remodeling and a better LV systolic function, thereby improving the NYHA functional class. It is unclear whether changes in the LV diastolic function may contribute to this favorable process.

Funding Acknowledgement

Type of funding source: None

Hormone replacement therapy for open heart surgery in a patient with panhypopituitarism and diabetes insipidus

We present an unusual case of a patient with panhypopituitarism and diabetes insipidus who underwent aortic valve replacement. We successfully managed these complicated endocrine disorders by using appropriate hormonal replacement therapy.

Pathological Role of Receptor for Advanced Glycation End Products in Calcified Aortic Valve Stenosis

Background Aortic stenosis (AS) is highly prevalent in patients with atherosclerotic cardiovascular disease. Advanced glycation end products (AGEs) and the receptor for AGEs (RAGE) play a pivotal role for vascular calcification in atherosclerosis. We hypothesize that the AGEs-RAGE axis could also be involved in the pathophysiological mechanism of calcified AS. Methods and Results A total of 54 patients with calcified AS who underwent aortic valve replacement were prospectively enrolled from 2014 to 2016 (mean age 75.3±7.7 years). Aortic valve specimens were obtained from 47 patients and 16 deceased control subjects without aortic valve disease (mean age 63.2±14.5 years). The valvular expression of RAGE was evaluated by immunohistochemistry. Serum levels of AGEs and soluble RAGE were measured in 50 patients with calcified AS and 70 age-matched and sex-matched control subjects without heart disease. The valvular RAGE expression in patients with calcified AS was higher than controls (P=0.004) and was significantly associated with a decreased ankle-brachial pressure index (P=0.007) and an increased intima-media thickness (P=0.026). RAGE and α-smooth muscle actin were coexpressed and were partially costained with osteocalcin and alkaline phosphatase. The serum levels of AGEs and soluble RAGE were significantly higher in the patients with calcified AS than in the controls (P=0.013 and P<0.001, respectively). Soluble RAGE (inversely) and use of aspirin were independently correlated with changes in left ventricular systolic function after aortic valve replacement (P=0.012 and P=0.002, respectively). Conclusions Our present study suggests that RAGE may play a role in the pathogenesis of calcified AS, which is a prognostic marker in patients with AS after aortic valve replacement.

Aortic valve replacement with or without concomitant coronary artery bypass grafting in very elderly patients aged 85 years and older

Degenerative aortic stenosis is the most common structural heart valve disease affecting the aging population. Catheter-based heart valve interventions are less invasive and very useful for very elderly patients. However, we often consider open heart surgery for these patients because of anatomical reasons and co-existing cardiac diseases, i.e., severe coronary artery disease. We aimed to analyze the outcomes of very elderly patients aged ≥ 85 years undergoing aortic valve replacement (AVR) with or without coronary artery bypass grafting (CABG). Twenty-nine very elderly patients aged ≥ 85 years who underwent AVR with CABG (n = 11, Group AC) or isolated AVR (n = 18, Group A) were examined. The overall mean age of the patients was 87.2 ± 2.6 (range 85-94) years. The estimated operative mortality rate, calculated using the Japan score, EuroSCORE II, and STS risk score, was 5.72%-10.88% in Group AC and 5.63%-8.30% in Group A. Aortic cross-clamp time (126.5 ± 29.0 vs. 96.9 ± 29.2 min, p = 0.016) was significantly longer in Group AC than in Group A. Although the major morbidity rate was higher in Group AC than in Group A (36% vs. 6%, p = 0.0336), the length of intensive care unit stay and hospital stay was comparable between both groups. There was no 30-day and hospital mortality in both groups. Eleven patients died during follow-up (senility, 5; cerebrovascular events, 2; renal failure, 1; unknown, 3). There were no significant differences in survival rates during follow-up (log-rank p value = 0.1051). The 1-, 2-, 3-, 4- and 5-year survival rates were 91%, 80%, 69%, 69% and 69%, respectively, in Group AC and 94%, 94%, 94%, 94% and 88%, respectively, in Group A. In conclusion, AVR with or without CABG could be safely performed in carefully selected very elderly patients with acceptable early- and long-term results. AVR with CABG in very elderly patients aged ≥ 85 offers similar results to isolated AVR in terms of 30-day mortality, hospital mortality, and long-term survival.

Multimodal imaging of cardiac-calcified amorphous tumor

Cardiac-calcified amorphous tumor (CAT) is a rare non-neoplastic tumor and its origin and pathogenesis are still unclear. In addition, it is difficult to clinically diagnose as cardiac CAT without pathological findings. We present a case of a 78-year-male diagnosed with cardiac CAT after surgical resection. We could evaluate tumor aspects by multimodal imaging including echocardiography, contrast-enhanced computed tomography (CT), magnetic resonance image, and 18F-fluorodeoxyglucose-positron emission tomography/CT before surgery.

Human lung microvascular endothelial cells as potential alternatives to human umbilical vein endothelial cells in bio-3D-printed trachea-like structures

BACKGROUND

We have been trying to produce scaffold-free structures for airway regeneration using a bio-3D-printer with spheroids, to avoid scaffold-associated risks such as infection. Previous studies have shown that human umbilical vein endothelial cells (HUVECs) play an important role in such structures, but HUVECs cannot be isolated from adult humans. The aim of this study was to identify alternatives to HUVECs for use in scaffold-free structures.

METHODS

Three types of structure were compared, made of chondrocytes and mesenchymal stem cells with HUVECs, human lung microvascular endothelial cells (HMVEC-Ls), and induced pluripotent stem cell (iPSC)-derived endothelial cells.

RESULTS

No significant difference in tensile strength was observed between the three groups. Histologically, some small capillary-like tube formations comprising CD31-positive cells were observed in all groups. The number and diameters of such formations were significantly lower in the iPSC-derived endothelial cell group than in other groups. Glycosaminoglycan content was significantly lower in the iPSC-derived endothelial cell group than in the HUVEC group, while no significant difference was observed between the HUVEC and HMVEC-L groups.

CONCLUSIONS

HMVEC-Ls can replace HUVECs as a cell source for scaffold-free trachea-like structures. However, some limitations were associated with iPSC-derived endothelial cells.

Left ventricular apical pseudoaneurysm with aortic prosthetic valve endocarditis

We report an 83-year-old man with a mycotic left ventricular apical pseudoaneurysm and aortic prosthetic valve endocarditis caused by Enterococcus spp. Mycotic left ventricular pseudoaneurysm is very rare and is associated with a high risk of rupture. Here, we report the clinical presentation, diagnosis, prognosis, and treatment of a case of mycotic left ventricular pseudoaneurysm to raise awareness regarding this unusual and potentially fatal complication.

P1038Device implantation after catheter ablation of paroxysmal atrial fibrillation with coexisting sick sinus syndrome: Insights from the Kansai Plus Atrial Fibrillation (KPAF) study

Background

Sick sinus syndrome (SSS) and atrial fibrillation (AF) frequently coexist and interact to initiate and perpetuate each other. Several retrospective or small cohort studies have suggested that successful catheter ablation of AF may help to waive device implantations in patients with paroxysmal AF plus SSS, however, no prospective large studies are so far available on this scenario.

Purpose

We aimed to elucidate the device implantation-free survival after catheter ablation of paroxysmal AF with coexisting SSS in a prospective large-scale registry. We also determined the risk factors for device implantations after catheter ablation of paroxysmal AF.

Methods

The Kansai Plus Atrial Fibrillation (KPAF) study is a multi-center prospective registry that enrolled 5,019 consecutive patients that underwent an initial pulmonary vein isolation-based radiofrequency catheter ablation of AF. This study was comprised of 3,226 patients with paroxysmal AF registered in the KPAF study (age, 64.8±10.5 years old; female, n=999 [31.0%]; left atrial diameter [LAD], 37.5±8.0 mm; left ventricular ejection fraction [LVEF], 65.3±8.4%, CHADS2 score, 1.09±1.05). The atrial tachyarrhythmia-free and device-free survivals after catheter ablation were compared between patients with SSS (n=368; tachy-brady syndrome, 88%) and without SSS (control; n=2,858).

Results

The atrial tachyarrhythmia-free survival was almost identical between the two groups both after the first ablation session (Fig.1A) and after the last procedure with an average of 1.3±0.5 sessions. At baseline, the devices had already been implanted in 53 (14.4%) SSS and 36 (1.3%) control patients. In the remaining patients, devices were newly implanted in 54 (17.1%) SSS and 62 (2.2%) control patients during the follow-up of 3 years after the catheter ablation (Figure 1B). In the SSS group, devices were implanted predominantly within 6 months after the catheter ablation, and atrial tachyarrhythmia recurrence preceded the device implantation in 48 (89%) patients. Multivariate predictors of device implantations after the paroxysmal AF ablation included: SSS (hazard ratio [HR] 6.85, 95% confidence interval [CI] 4.61–10.19, p<0.001), an age>75 years old (HR 1.69, 95% CI 1.08–2.64, p=0.019), a female gender (HR 2.16, 95% CI 1.44–3.24, p<0.001), the LAD (mm) (HR 1.05, 95% CI 1.02–1.08, p=0.006), and the LVEF (%) (95% CI 0.96, 95% CI 0.94–0.98, p<0.001).

Figure 1

Conclusions

Device implantations could be waived in >80% of patients with SSS at 3 years of follow-up after the catheter ablation of paroxysmal AF in this real world all comer prospective registry. In addition to coexisting SSS, predictors of device implantations after paroxysmal AF ablation included: the elderly, a female gender, a large LA, and a reduced LVEF.

Acknowledgement/Funding

None

Florida sleeve technique for a right sinus of Valsalva aneurysm: a case report

BACKGROUND

Florida sleeve technique was reported by Hess et al. as a new technique of valve sparing aortic root replacement without the requirement of entire aortic root wall resection and coronary artery reconstruction. We present a rare case of an unruptured aneurysm of the right sinus of Valsalva that was successfully treated with resection of the aneurysm and the Florida sleeve technique.

CASE PRESENTATION

A 72-year-old man was admitted for the treatment of an unruptured aneurysm of the right sinus of Valsalva. Computed tomography showed an aneurysm of the right sinus of Valsalva measuring > 40 mm and protruding into the right ventricular outflow tract. The aneurysm dilated up to 5 mm per year, and the left sinus of Valsalva and non-coronary sinus of Valsalva also showed dilation, and he underwent resection of only the right sinus of Valsalva aneurysm and valve sparing aortic root replacement with the Florida sleeve technique.

CONCLUSIONS

We performed valve-sparing aortic root replacement with the Florida sleeve technique. It could reduce surgical risks and prevent a dilatation of the residual sinus of Valsalva through coverage with a graft for a long term.