Impact of sarcopenia on long-term survival after cardiac surgery for end-stage renal disease patients.

BACKGROUND: The long-term mortality of end-stage renal disease (ESRD) patients is still unsatisfactory. Therefore, long-term risk assessments in ESRD patients undergoing cardiac surgery are needed. Recently, sarcopenia is major concern in cardiac surgery because of its association with poor long-term survival. However, the impact of sarcopenia on the long-term survival of ESRD patients undergoing cardiac surgery is not well understood. METHODS: Eighty-two ESRD patients who underwent elective cardiac surgery were enrolled. Sarcopenia was identified based on noncontrast abdominal computed tomography. The impact of preoperative and intraoperative factors on long-term survival was investigated. RESULTS: Forty-three patients (52%) were diagnosed with sarcopenia. The in-hospital mortality rate was 4.9%. The 5-year overall survival rate was 48%. The multivariate analyses revealed that STS score ≥ 4 (odds ratio, 6.0; confidence interval, 2.5-14.7; p < 0.01) and presence of sarcopenia (odds ratio, 2.4; confidence interval, 1.3-4.5; p = 0.03) were independent risk factors for overall survival. The 5-year survival rates of low-risk (Society of Thoracic Surgeons score of < 4) patients without sarcopenia, low-risk with sarcopenia, more than intermediate-risk (Society of Thoracic Surgeons score of ≥ 4) without sarcopenia, and more than intermediate-risk with sarcopenia groups were 80%, 51%, 50%, and 26%, respectively. CONCLUSIONS: Among the ESRD patients, the low risk without sarcopenia group showed an excellent long-term survival, in contrast to more than intermediate-risk patients with sarcopenia, who can expect poor long-term survival. Preoperative assessment of sarcopenia in addition to the surgical risk score can be useful in developing a therapeutic strategy.

Protective role of stratum corneum in percutaneous Leptospira infection in a hamster model.

Leptospira enters humans and animals through injured skin or mucous membranes by direct or indirect contact with urine excreted from infected reservoirs. Individuals with cut or scratched skin are at high risk of infection and are recommended to be protected from contact with Leptospira, but the risk of infection via skin without apparent wounds is unknown. We hypothesized that the stratum corneum of the epidermis might prevent percutaneous invasion of leptospires. We established a stratum corneum deficient model of hamsters using the tape stripping method. The mortality rate of hamsters lacking stratum corneum that were exposed to Leptospira was higher than that of controls with shaved skin, and was not significantly different from an epidermal wound group. These results indicated that the stratum corneum plays a critical role in protecting the host against leptospiral entry. We also examined the migration of leptospires through the monolayer of HaCaT cells (human keratinocyte cell line) using Transwell. The number of pathogenic leptospires penetrating the HaCaT cell monolayers was higher than that of non-pathogenic leptospires. Furthermore, scanning and transmission electron microscopic observations revealed that the bacteria penetrated the cell monolayers through both intracellular and intercellular routes. This suggested that pathogenic Leptospira can migrate easily through keratinocyte layers and is associated with virulence. Our study further highlights the importance of the stratum corneum as a critical barrier against the invasion of Leptospira found in contaminated soil and water. Hence, preventative measures against contact infection should be taken, even without visible skin wounds.

Dissemination of Leptospira into the intestinal tract resulting in fecal excretion in a hamster model of subcutaneous infection with Leptospirainterrogans.

Leptospirosis, caused by pathogenic Leptospira, is one of the most common zoonotic diseases in the world. It is transmitted to humans through the skin and mucous membranes by contact with water or soil contaminated with urine excreted from infected animals. In human infections, gastrointestinal symptoms such as abdominal pain, vomiting, and diarrhea have been frequently observed, but there have been no reports analyzing gastrointestinal lesions in leptospirosis, and the pathological mechanism of gastrointestinal symptoms in leptospirosis remains unclear. In this study, we investigated the pathological changes and the distribution of leptospires in the intestinal wall, and the presence of leptospires in the intestinal contents and feces, of hamsters subcutaneously infected with Leptospira interrogans. Results showed that infected hamsters had macroscopic redness in the jejunum and ileum. Submucosal hemorrhage was observed histologically, and there was no infiltration of inflammatory cells such as neutrophils. There were no obvious changes in the colon, either macroscopically or histologically, and the feces were normal (solid stools). Leptospira was isolated from all the intestinal walls from the small intestine to the colon, the intestinal contents, and the feces. These findings suggest that the invasion of leptospires into the intestinal wall and the associated submucosal hemorrhage may be the cause of the gastrointestinal symptoms observed in leptospirosis. Furthermore, not only the urine of infected animals but also the feces could be a source of infection.

Significant delayed aortic dilatation after tetralogy of Fallot repair: a case report.

BACKGROUND: Aortic dilatation may occur in some patients even after complete repair of tetralogy of Fallot (TOF). The progression rate of the aortic diameter is so slow, and the incidence of aortic dissection is so low that it is suspected that frequent imaging of the aorta may not be necessary. CASE PRESENTATION: We describe an asymptomatic 41-year-old man with hypertension in whom aortic dilatation was accidentally discovered 39 years after TOF repair. He underwent ambulatory follow-up without any difficulty for 21 years after the repair. Contrast-enhanced computed tomography revealed significant aortic dilatation (maximum diameter of 88 mm at the sinus of Valsalva), and echocardiography revealed severe aortic regurgitation, which seemed to progress during the last 18 years without any evaluation or follow-up. The Bentall procedure was successfully performed using a valved graft, under deep hypothermic circulatory arrest with antegrade cerebral perfusion, and his postoperative course was uneventful. Histopathological examination of ascending aorta specimens revealed severe cystic medial degeneration. CONCLUSIONS: Keeping in mind that a patient with rapid progression of the aortic dilatation after TOF repair exist, periodic follow-up for evaluation of the aorta is essential in patients with TOF.

A case of cardiac strangulation following epicardial pacemaker implantation.

An 8-year-old boy had undergone permanent epicardial pacemaker implantation with a Y-shaped bipolar ventricular lead on day 6 after birth for treatment of congenital complete atrioventricular block. He was found to have pulmonary stenosis and mitral stenosis by follow-up echocardiography. Further studies including computed tomography and cardiac catheterization revealed that the pacemaker lead had completely encircled the cardiac silhouette and was in a state of "cardiac strangulation". We removed the previous pacing leads and generator and implanted a new epicardial dual-chamber pacing system in the right atrium and right ventricle. Additionally, an expanded polytetrafluoroethylene sheet was placed between the new leads and the heart to prevent recurrence of cardiac strangulation.

Surgical Therapy for Patients with Severe Aortic Stenosis in the Era of Transcatheter Aortic Valve Replacement.

Aortic stenosis (AS) is the most common valvular heart disease and is most frequently recognized among elderly people. Surgical aortic valve replacement (SAVR) is the most effective therapy, but its indication is sometimes difficult, and is impossible for high operative risk patients. Transcatheter aortic valve replacement (TAVR) was recently approved in Japan for high risk and inoperable patients with severe AS. TAVR is a less invasive method because it does not require a cardiopulmonary bypass and is associated with excellent surgical outcomes. In Western countries, the indication of TAVR has already been extended to moderate operative risk patients with severe AS, and is going to be further extended to low risk patients. The number of patients undergoing TAVR is increasing progressively, and there are effective alternative therapies for patients with severe AS. Selection of these surgical methods will be important in the near future. In regard to low operative risk patients especially, not only operative mortality, but also long-tern mortality and morbidity and quality of life should be taken into consideration. It is considered that some comorbidities in AS patients will be revealed to have an impact on surgical outcomes at the time when these surgical methods are selected. In this review, we examine end-stage renal disease on hemodialysis, functional tricuspid regurgitation, and sigmoid septum, and give an outline of what influence SAVR and TAVR have on the surgical outcomes of severe AS patients.

Use of computed tomography-guided biopsy to detect Peptostreptococcus micros-induced mycotic abdominal aortic aneurysm after endovascular repair.

Mycotic aortic aneurysm (MAA) is rare but lethal. Detection of the causative bacteria is important for successful treatment. In some cases, however, no micro-organisms are detected by repeated blood cultures. Open surgery is the standard procedure for MAA, but endovascular intervention is also performed. An aneurysm specimen cannot be taken for culture when using an endovascular approach, decreasing the opportunity to detect the causative organism. We performed successful endovascular repair in a rare case of a Peptostreptococcus micros-induced MAA as detected by postoperative computed tomography-guided biopsy. This case may help to establish appropriate medical treatment for MAAs.

Endovascular Repair for Ruptured Axillary Artery Aneurysm Proximal to Hemodialysis Access.

Axillary artery aneurysms are uncommon and potentially high-risk lesions threatening the upper extremities. In hemodialysis patients, arteriovenous fistulae creation rarely triggers aneurysmal degeneration and arterial aneurysms in inflow arteries. These aneurysms are usually treated by surgical repair. However, this may lead to complications because of the anatomical complexity surrounding aneurysms of axillary arteries. We report a patient undergoing hemodialysis who had a ruptured ipsilateral axillary artery aneurysm proximal to vascular access. We successfully treated it by endovascular repair with the GORE Excluder AAA contralateral leg endoprosthesis, approaching from the left brachial artery proximal to the shunt. No complications occurred during 15 months after the endovascular repair.

Size and Stiffness of the Pulmonary Autograft after the Ross Procedure in Children.

Progressive dilatation of the pulmonary autograft is one of the greatest concerns after the Ross procedure. Increased stress in the arterial wall may cause changes in the elastic properties of the pulmonary autograft, and thus lead to pathological dilatation. The present study aimed to investigate the changes in the autograft diameter and stiffness during follow-up after the Ross procedure. A total of ten patients underwent the Ross procedure at our institution between 2003 and 2011. Echocardiography was used to measure the diameters of the pulmonary autograft at the level of the annulus, sinus of Valsalva, and sinotubular junction. The stiffness index was calculated from the angiographic data, and compared with that of 16 age-matched control children. The diameters of the pulmonary autograft increased throughout the follow-up period, particularly at the level of the sinus of Valsalva and at the sinotubular junction. The aortic root was stiffer in Ross patients compared with control children (7.9 ± 1.8 vs. 3.9 ± 0.7 immediately postoperatively, p < 0.01; 10.1 ± 2.8 vs. 4.2 ± 1.4 at 5 years postoperatively, p < 0.01). Although no significant relationship was found between the stiffness index and the autograft diameter, the stiffness index tended to increase over time. Dilatation of the pulmonary autograft was accompanied by progressive change in aortic stiffness. Longer follow-up is warranted to clarify the impact of this change in aortic stiffness on autograft failure.