Aortic endograft infection by Mycobacterium abscessus subsp. massiliense with acquired clarithromycin resistance: a case report.

BACKGROUND: Mycobacterium abscessus subsp. massiliense (MMA) comprises a group of non-tuberculous, rapidly growing mycobacteria. Although MMA can cause pulmonary diseases, surgical site infections, and disseminated diseases, aortic endograft infection has not been reported. Here, we describe the first case of aortic endograft infection caused by MMA. CASE PRESENTATION: Two months after stent-graft insertion for an abdominal aortic aneurysm, an 85-year-old man was admitted with fever and abdominal pain and was diagnosed with aortic endograft infection. Despite 14 days of meropenem and vancomycin intravenous administration, periaortic fluid pooling increased as compared to that before antibiotic administration. The abscess was drained, and fluorescent acid-fast staining of the abscess fluid revealed bacilli. We conducted genetic tests on the genes hsp65, rpoB, and sodA, performed Whole Genome Sequencing (WGS), and identified the organism as MMA. Intravenous imipenem-cilastatin (IPM/CS), amikacin (AMK), and oral clarithromycin (CAM) were administered. After 2 months, oral CAM and sitafloxacin were administered because the abscess had decreased in size. However, after 6 weeks, the abscess increased in size again. Antimicrobial susceptibility testing of the drainage fluid from the abscess resulted in the isolation of an MMA strain that had acquired resistance to CAM. Intravenous IPM/CS, AMK, and oral linezolid were added to the treatment regimen along with oral CAM and STFX. However, he was not fully cured and died 6 months later. Neither the full-length erythromycin ribosome methyltransferase (erm)(41) gene nor the rrl or rpIV gene mutations were found by Sanger sequencing in the pre- and post-treatment strains. Whole-genome sequence analysis of the post-treatment strain revealed mutations in genes with no previous reports of association with macrolide resistance. CONCLUSIONS: Aortic endograft infection caused by MMA strain is extremely rare; nonetheless, MMA should be suspected as the causative microorganism when broad-spectrum antimicrobials are ineffective.

[Esophageal Perforation on Transesophageal Echocardiography in Open-heart Surgery:Report of a Case].

A 70-year-old woman, who was taking prednisolone to treat Takayasu arteritis, underwent surgery for aortic regurgitation and aneurysm of the ascending aorta. The probe of the transesophageal echocardiography (TEE) could not be inserted due to resistance during anesthesia induction and was inserted after starting cardiopulmonary bypass. The right pneumothorax was observed during surgery. After surgery, fever and a high C-reactive protein level continued, and a computed tomography (CT) examination revealed right thoracic empyema together with free air around the esophagus. The esophageal perforation diagnosis was confirmed by upper endoscopy. Esophageal leakage continued despite emergency esophageal repair and enterostomy. Although esophagectomy was performed 2 months later, the patient died 6 months after cardiac surgery due to sepsis. Thus, esophageal perforation related to TEE in open-heart surgery was considered to be associated with a poor prognosis.

Severe Heart Failure in a Young Cocaine User.

A 27-year-old Caucasian male traveler with well-controlled asthma was admitted to our hospital because of severe heart failure (HF). He had a history of cocaine use. Transthoracic echocardiography (TTE) showed severe diffuse hypokinesis of the left ventricle (LV) and a large mobile thrombus in the LV. He was treated with diuretics, inotropes and anticoagulants which led to small improvements in the HF and LV thrombus, however, he needed to undergo left ventricular assist device (LVAD) implantation and surgical removal of a residual LV thrombus due to inotrope-dependency.It is necessary to consider the possibility of cocaine or illicit drug use in a young individual with cardiovascular disease or sudden death even in Japan where cocaine and drugs are prohibited by law, as recreational drug use has been increasing in many countries around the world.

Early Extubation in the Operating Room after Congenital Open-Heart Surgery.

Early extubation in the operating room after congenital open-heart surgery is feasible, but extubation in the intensive care unit after the operation remains common practice at many institutions. The purpose of this study was to evaluate retrospectively the adequacy of our early-extubation strategy and exclusion criteria through analysis based on the Risk Adjustment in Congenital Heart Surgery method (RACHS-1).This retrospective analysis included 359 cases requiring cardiopulmonary bypass (male, 195; female, 164; weight > 3.0 kg; aged 1 month to 18 years). Neonates and preoperatively intubated patients were excluded. Other exclusion criteria included severe preoperative pulmonary hypertension, high-dose catecholamine requirement after cardiopulmonary bypass, delayed sternal closure, laryngomalacia, serious bleeding, and delayed awakening. The early-extubation rates were compared between age groups and RACHS-1 classes.Overall, 83% of cases (298/359) were extubated in the operating room, classified by RACHS-1 categories as follows: 1, 59/59 (100%); 2, 164/200 (84%); 3, 61/78 (78%); and 4-6, 10/22 (45%). The early extubation rate in categories 1-3 (86%, 288/337) was significantly higher than for categories 4-6 (45.5%, 10/22) (P < 0.001). Because they met one of the exclusion criteria, 61 patients (17%) were not extubated in the operating room. Eight patients (2.7%) required re-intubation after early extubation in the operating room, and longer operation time was significantly associated with re-intubation (P < 0.001).Extubation in the operating room after congenital open-heart surgery was feasible based on our criteria, especially for patients in the low RACHS-1 categories, and involves a very low rate of re-intubation.

Energy dynamics of the intraventricular vortex after mitral valve surgery.

Mitral valve morphology after mitral valve surgery affects postoperative intraventricular flow patterns and long-term cardiac performance. We visualized ventricular flow by echocardiography vector flow mapping (VFM) to reveal the impact of different mitral valve procedures. Eleven cases of mechanical mitral valve replacement (nine in the anti-anatomical and two in the anatomical position), three bioprosthetic mitral valve replacements, and four mitral valve repairs were evaluated. The mean age at the procedure was 57.4 ± 17.8 year, and the echocardiography VFM in the apical long-axis view was performed 119.9 ± 126.7 months later. Flow energy loss (EL), kinetic pressure (KP), and the flow energy efficiency ratio (EL/KP) were measured. The cases with MVR in the anatomical position and with valve repair had normal vortex directionality ("Clockwise"; N = 6), whereas those with MVR in the anti-anatomical position and with a bioprosthetic mitral valve had the vortex in the opposite direction ("Counterclockwise"; N = 12). During diastole, vortex direction had no effect on EL ("Clockwise": 0.080 ± 0.025 W/m; "Counterclockwise": 0.083 ± 0.048 W/m; P = 0.31) or KP ("Clockwise": 0.117 ± 0.021 N; "Counterclockwise": 0.099 ± 0.057 N; P = 0.023). However, during systole, the EL/KP ratio was significantly higher in the "Counterclockwise" vortex than that in the "Clockwise" vortex (1.056 ± 0.463 vs. 0.617 ± 0.158; P = 0.009). MVP and MVR with a mechanical valve in the anatomical position preserve the physiological vortex, whereas MVR with a mechanical valve in the anti-anatomical position and a bioprosthetic mitral valve generate inefficient vortex flow patterns, resulting in a potential increase in excessive cardiac workload.

Factors associated with a low initial cerebral oxygen saturation value in patients undergoing cardiac surgery.

Regional cerebral oximetry using near-infrared spectroscopy device, an INVOS 5100 C (Medtronic, Minneapolis, MN, USA), during cardiac surgery aims to avoid perioperative neurological impairment, especially during cardiopulmonary bypass. However, it is not uncommon to encounter critically low initial cerebral regional oxygen saturation or a low value unresponsive to intervention. Therefore, it is important to identify factors associated with low saturation value other than true cerebral hypoxia. We investigated the relationship between preoperative regional cerebral oxygen saturation and clinical variables during cardiac surgery. From January 2013 to May 2016, 462 patients underwent elective cardiac surgery. Patient's ≤12 years of age, with acute cerebral infarction, with previous intracranial hemorrhage or neurosurgery, with concomitant aortic surgery, and having off-pump coronary artery bypass surgery were excluded. The remaining 223 patients were monitored by intraoperative regional cerebral oximetry. Univariate analysis found that scalp-cortex distance, cerebrospinal fluid thickness, left ventricular ejection fraction, hemoglobin concentration, estimated glomerular filtration rate, and hemodialysis were significantly correlated with the initial regional oxygen saturation value. Multiple regression analysis revealed that scalp-cortex distance, left ventricular ejection fraction, hemoglobin, and hemodialysis remained as significant variables. A receiver operating characteristic analysis found that for a low initial regional oxygen saturation value of 40%, the thresholds of scalp-cortex distance, left ventricular ejection fraction, and hemoglobin concentration were 17.6 mm, 45.2%, and 7.5 g/dl, respectively. In conclusion, brain atrophy, poor left ventricular function, anemia, and hemodialysis were associated with low initial cerebral regional oxygen saturation values in adult cardiac surgery patients.

Impact of top end anastomosis design on patency and flow stability in coronary artery bypass grafting.

For coronary artery bypass grafting (CABG), free grafts such as a saphenous vein or radial artery are often used for grafts to the lateral and posterior walls. However, the relationship between top-end anastomosis design and long-term patency remains unknown. Because coronary artery blood flow is dominant during diastole, top-end anastomosis may work better if the graft is directed towards the apex, whereas the shortest graft pathway appears to be most efficient. Using computational fluid dynamic models, we evaluated the hemodynamic variables that were affected by the angle of the top-end anastomosis. We created three-dimensional geometries of the aortic root with coronary arteries that involved 75 % stenosis in the obtuse marginal and postero-lateral branches. Two bypass models under vasodilator administration were created: in a"Model A", the top-end anastomosis is parallel to the long axis of the ascending aorta and the graft passed over the conus directed towards the apex; in a "Model B", the top-end anastomosis is directed toward the shortest pathway, and form near the right angles to the long axis of the ascending aorta. Wall shear stress (WSS) and its fluctuation, an oscillatory shear index (OSI) were evaluated to predict fibrosis progression at the anastomosis site and graft flow. Graft flow was 197.3 ml/min and 207.3 ml/min in the "Model A" and "Model B", respectively. The minimal WSS value inside the graft with the "Model A" and "Model B" was 0.53 Pa and 4.09 Pa, respectively, and the OSI value was 0.46 and 0.04, respectively. The top-end anastomosis of a free graft should be directed vertically towards the aorta to achieve the shortest graft pathway to maintain a high graft flow rate and to avoid the risks of endothelial fibrosis and plaque progression over the long-term after CABG.

Synchronization of the Flow and Pressure Waves Obtained With Non-Simultaneous Multipoint Measurements.

The use of measured data as boundary conditions renders hemodynamic simulations more patient-specific. However, synchronized acquisition of data at multiple locations is often difficult in clinical practice. This study proposes a method for resynchronizing measured data for use as boundary conditions for flow simulations using frequency analyses, and discusses the optimal cut-off frequency for differentiating cardiac and respiratory variation in hemodynamic data during resynchronization. To demonstrate the utility of the method, a Fontan circulation, which is the final palliative result with single-ventricle physiology, was used. The results suggest that it is optimal to set a cut-off frequency that gives a local minimum in the power spectrum that is slightly lower than the peak frequency of the heartbeat. Additionally, the total energy loss depended on the cut-off frequency, although the overall flow patterns appeared to be similar. The method is applicable to cardiovascular systems other than the Fontan circulation, where hemodynamic data with multifactorial fluctuations are required at various locations but simultaneous measurements are not possible.

Norwood Procedure Performed on a Patient With Trisomy 13.

Trisomy 13 is associated with a variety of congenital anomalies, some of which are life-threatening and related to poor prognosis. Therefore, cardiac surgery is rarely offered to these patients, especially to those with complex cardiac anomalies. We report the case of a neonate weighing 2324 g who was born with severe congenital heart defects. Transthoracic echocardiography revealed the diagnoses of asplenia, single ventricle, aortic stenosis, coarctation of the aorta, hypoplastic aortic arch, and total anomalous pulmonary venous return. She was hemodynamically unstable. Palliative Norwood procedure with right ventricle-pulmonary artery conduit (RV-PA conduit) was performed at the age of 1 day to save her life. On postoperative day 7, chromosome analysis revealed trisomy 13. Echocardiography revealed good heart function; stable hemodynamic status was achieved with minimal amounts of inotropic agents. However, she developed anuria, which did not improve despite situational possible interventions, including peritoneal dialysis and continuous hemodiafiltration. On postoperative day 37, she succumbed to sudden cardiorespiratory failure. Nevertheless, this case indicates that a neonate with trisomy 13 can have a better chance at survival with cardiac surgery such as the Norwood procedure with an RV-PA conduit.

Seventeen-month-long paracorporeal biventricular mechanical support as a bridge to transplantation for severe dilated cardiomyopathy.

The long-term management of paracorporeal biventricular assist devices (BiVAD) is difficult because of significant risks of bleeding, thrombosis, and infection. Here we report the case of a 41-year-old woman with severe dilated cardiomyopathy who developed serious cerebral bleeding after receiving a paracorporeal BiVAD but recovered well after treatment. She eventually underwent cardiac transplantation 17 months after implantation of the paracorporeal BiVAD.

Optimal Graft Size of Modified Blalock-Taussig Shunt for Biventricular Circulation in Neonates and Small Infants.

The modified Blalock-Taussig shunt (mBTS) is one of the most important palliative procedures in congenital heart surgery. However, in neonates and small infants, operative mortality and morbidity due to excessive pulmonary blood flow or shunt failure remains high. In this study, a small shunt graft (3.0-mm diameter) was estimated to determine the optimal shunt graft size of BTS as an initial palliation for ultimate biventricular circulation. Eighteen patients weighing an average 3.5 kg who underwent mBTS from July 2004 to January 2013 at our institute were reviewed. We divided the study cohort into two groups: group S (n = 10) included patients with 3.0-mm diameter shunt grafts, and group L (n = 8) included patients with 3.5-mm diameter shunt grafts. There were no hospital deaths or shunt occlusion in either group. One group L patient (12.5%) had cardiogenic shock due to excessive pulmonary blood flow. There were no differences in postoperative arterial oxygen saturation (SaO2) between the groups. There were no differences in body weight at intracardiac repair (ICR) between the groups. During the interstage to ICR, body weight gain was significantly greater in group S than in group L (P = 0.008). The small shunt graft (3.0-mm diameter) in BTS was safe, provided adequate pulmonary blood flow, and led to significant weight gain between mBTS and ICR for ultimate biventricular circulation in neonates and small infants with low body weight.

Effect of additional preoperative administration of the neutrophil elastase inhibitor sivelestat on perioperative inflammatory response after pediatric heart surgery with cardiopulmonary bypass.

Cardiopulmonary bypass (CPB) elicits a systemic inflammatory response. Our previous reports revealed that prophylactic sivelestat administration at CPB initiation suppresses the postoperative acute inflammatory response due to CPB in pediatric cardiac surgery. The purpose of this study was to compare the effects of sivelestat administration before CPB and at CPB initiation in patients undergoing pediatric open-heart surgery. Twenty consecutive patients weighing 5-10 kg and undergoing ventricular septal defect closure with CPB were divided into pre-CPB (n = 10) and control (n = 10) groups. Patients in the pre-CPB group received a 24 h continuous intravenous infusion of 0.2 mg/kg/h sivelestat starting at the induction of anesthesia and an additional 0.1 mg/100 mL during CPB priming. Patients in the control group received a 24-h continuous intravenous infusion of 0.2 mg/kg/h sivelestat starting at the commencement of CPB. Blood samples were tested. Clinical variables including blood loss, water balance, systemic vascular resistance index, and the ratio between partial pressure of oxygen and fraction of inspired oxygen (P/F ratio) were assessed. White blood cell count and neutrophil count as well as C-reactive protein levels were significantly lower in the pre-CPB group according to repeated two-way analysis of variance, whereas platelet count was significantly higher. During CPB, mixed venous oxygen saturation remained significantly higher and lactate levels lower in the pre-CPB group. Postoperative alanine aminotransferase and blood urea nitrogen levels were significantly lower in the pre-CPB group than in the control group. The P/F ratio was significantly higher in the pre-CPB group than in the control group. Fluid load requirement was significantly lower in the pre-CPB group.Administration of sivelestat before CPB initiation is more effective than administration at initiation for the suppression of inflammatory responses due to CPB in pediatric open-heart surgery, with this effect being confirmed by clinical evidence.

A case of thrombosis of intra-atrial extracardiac conduit and left pulmonary artery due to infective endocarditis after modified Fontan operation.

Previous studies have reported that the extracardiac Fontan procedure has excellent outcomes and a lower incidence of postoperative complications than the lateral tunnel procedure. However, thromboembolic events that occur after the Fontan procedure are a well-known cause of morbidity. We experienced a case of thrombosis of intra-atrial extracardiac conduit and the left pulmonary artery 2 years after a modified Fontan operation due to infective endocarditis (IE) despite prophylactic antiplatelet therapy. The patient underwent reoperation. The conduit in the right atrium (RA) was excised, and the thrombus in the vessels was removed. Because the fibrous tissue in the RA around the conduit was firm, the tissue was used as the "tunnel" for the Fontan route between the IVC and the ePTFE graft outside the RA instead of replacement using another alien graft. He was discharged on postoperative day 45 and was medicated with coumadin and aspirin. He is now being followed in our outpatient clinic and is still without any sign of infection.

Degos disease complicated by constrictive pericarditis in remote phase: a case report.

BACKGROUND: Degos disease, also known as malignant atrophic papulosis, is characterised by cutaneous manifestations due to chronic thrombo-obliterative vasculopathy. There have been reports of the rare late-onset Degos disease complicated by constrictive pericarditis (CP). This study reports a case of CP caused by Degos disease that developed 20 years after diagnosis. CASE PRESENTATION: A 62-year-old woman who had been taking aspirin for 20 years for Degos disease was hospitalised for worsening of heart failure. The patient was diagnosed with CP and underwent pericardiectomy. Pathological findings suggested the involvement of Degos disease. The postoperative course was uneventful, and her heart failure and Degos disease did not worsen. CONCLUSIONS: The study findings suggests that Degos disease can cause long-term CP. Aspirin effectively inhibited the progression of Degos disease, and surgical treatment was necessary when heart failure due to CP was refractory to treatment.

A Case of Vascular Graft Infection Caused by Haemophilus parainfluenzae.

Haemophilus parainfluenzae is a gram-negative coccobacillus that is a part of the normal flora in the human upper airway and sometimes causes infective endocarditis. We present a case of a 68-year-old Japanese man who had vascular graft infection caused by H. parainfluenzae 4 years after surgery for chronic aortic dissection.

Novel implantable device to detect cardiac allograft rejection.

BACKGROUND: Allograft rejection remains the nemesis of solid organ transplantation. Soul Mate is a novel implantable wireless data transmission system that analyzes 9 intramyocardial electrogram parameters recorded from 4 or 6 configurations of 2 or 3 epicardial leads to detect allograft rejection. This study determined the ability of the Soul Mate to detect early rejection of transplanted hearts. METHODS AND RESULTS: Five dogs underwent heterotopic cervical heart transplantation and simultaneous implantation of the Soul Mate's Cardiac Rejection Monitoring Device. Dogs were initially immunosuppressed, but subsequent drug discontinuation allowed allograft rejection to appear. Allograft biopsies were performed at regular intervals to determine rejection grade, which was compared to a calculated rejection score determined as percent change from baseline of values for each intramyocardial electrogram. There was significant correlation between the biopsy results and the evolution of 5 parameters. The strongest correlation (r=0.939; P<0.001) was obtained using the "general median" parameter from 4 configurations, assessed 1 day before the biopsy, with a sensitivity of 85.7% and a specificity of 100% compared to the myocardial biopsy results. CONCLUSIONS: The Soul Mate allograft rejection monitoring system accurately detected transplanted heart rejection in a canine model noninvasively with continuous sampling. This proof-of-concept study suggests that the Soul Mate could be used to more intensely and more frequently monitor cardiac allografts for rejection.

In vivo evaluation of zirconia ceramic in the DexAide right ventricular assist device journal bearing.

Zirconia is a ceramic with material properties ideal for journal bearing applications. The purpose of this study was to evaluate the use of zirconium oxide (zirconia) as a blood journal bearing material in the DexAide right ventricular assist device. Zirconia ceramic was used instead of titanium to manufacture the DexAide stator housing without changing the stator geometry or the remaining pump hardware components. Pump hydraulic performance, journal bearing reliability, biocompatibility, and motor efficiency data of the zirconia stator were evaluated in six chronic bovine experiments for 14-91 days and compared with data from chronic experiments using the titanium stator. Pump performance data including average in vivo pump flows and speeds using a zirconia stator showed no statistically significant difference to the average values for 16 prior titanium stator in vivo studies, with the exception of a 19% reduction in power consumption. Indices of hemolysis were comparable for both stator types. Results of coagulation assays and platelet aggregation tests for the zirconia stator implants showed no device-induced increase in platelet activation. Postexplant evaluation of the zirconia journal bearing surfaces showed no biologic deposition in any of the implants. In conclusion, zirconia ceramic can be used as a hemocompatible material to improve motor efficiency while maintaining hydraulic performance in a blood journal bearing application.

Prosthetic valve endocarditis presenting with back pain alone: A case report.

We report a case of a 64-year-old woman with a past medical history (PMH) of prosthetic valve replacement 7 months prior to admission, who presented with only right back pain. Physical examination revealed one conjunctival spot hemorrhage and a mild systolic murmur. Blood cultures were positive for methicillin-resistant Staphylococcus epidermidis. Trans-esophageal echocardiography revealed aortic valve vegetations; hence, a diagnosis of prosthetic valve endocarditis (PVE) was made. Clinical presentation of infective endocarditis varies and sometimes mimics that of polymyalgia rheumatica. The patient was diagnosed as PVE considering the whole clinical picture including the patient's PMH, physical examination, and blood cultures.

Endovascular Therapy for Chronic Type B Aortic Dissection.

Objectives: Endovascular repair of the thoracic aorta (TEVAR) represents a therapeutic option for type B aortic dissection. However, the optimal timing for TEVAR is controversial. We examined the outcomes of TEVAR for chronic type B dissection and reviewed aortic morphology using pre- and postoperative CT scan images. Methods: Between 2012 and 2017, 12 patients underwent TEVAR for chronic type B dissection at our institution. We retrospectively reviewed the clinical and operative data including CT scan images, comparing the values between early group (5 cases, 3 months to 1 year from initial dissection) and late group (7 cases, more than 1 year from initial dissection). Results: There were no paraplegia, stroke, and death in our cohort. There was no difference in degree of the aortic remodeling between two groups. Conclusions: Outcomes after TEVAR for chronic type B aortic dissection were favorable. Aortic remodeling could be obtained in selected patients by closing an entry with TEVAR procedure. (This is a translation of Jpn J Vasc Surg 2018; 27: 281-287.).

Novel surgical strategy for complicated pulmonary stenosis using haemodynamic analysis based on a virtual operation with numerical flow analysis.

OBJECTIVES: A novel surgical strategy using haemodynamic analyses based on virtual operations with computational simulations has been introduced for complicated pulmonary stenosis. We evaluated the efficacy of this strategy. METHODS: Six patients were enrolled. Before surgery, the optimal pulmonary arteries were constructed based on computational fluid dynamics using 3-dimensional computed tomography. Energy loss (EL, mW) and wall shear stress (WSS, Pa) were calculated. We compared the shapes of preoperative and optimal pulmonary arteries to determine the surgical strategy, including the incision line and the shape of the patch (virtual surgery). EL and WSS were compared between virtual and actual surgeries using flow analysis. RESULTS: In both the virtual and actual surgeries, postoperative EL tended to be lower than the preoperative EL, although there were no significant differences (P = 0.12 and P = 0.17, respectively). The mean WSS in the virtual surgery was significantly reduced from 112 ± 130 Pa to 25 ± 24 Pa (P = 0.028). After the actual surgery, the mean WSS was also significantly reduced to 30 ± 23 Pa (P = 0.047). There were no significant differences in the values for EL and WSS before and after surgery or between virtual and actual surgery (P = 0.94 and P = 0.85, respectively). CONCLUSIONS: Pulmonary artery plasty, using computational fluid dynamics based on virtual surgery, is an efficient surgical strategy. This novel strategy can easily and successfully provide an optimal pulmonary artery plasty equivalent to that using the conventional approach, which is based on the surgeon's personal experience and judgement.