Recommendations on echocardiography following surgical aortic valve replacement (SAVR): time for revision?

Background

ESC guidelines recommend annual echocardiographic evaluation following biological surgical aortic valve replacement (SAVR), and 5 years following mechanical SAVR. Conversely, increased life expectancy result in increasing demand on health care resources.

Purpose

To assess aortic reintervention rates at 1-year, 3-year and 5-year following biological and mechanical SAVR in relation to estimated echocardiographic controls.

Methods

From the nationwide Danish Register of Surgical Procedures, we identified all patients ≥40 years with isolated biological or mechanical SAVR +/− concomitant coronary artery bypass graft surgery (CABG) during 2000–2016. In 90-day reintervention-free survivors we assessed aortic valve reintervention rates at 1-year, 3-years and 5-years until December 31st, 2017. We further assessed cumulative risk of reintervention by age (<60, 60–69, 70–79, ≥80 years at SAVR) accounting for the competing risk of death during the study period.

Results

The population of 90-day reintervention-free survivors included 10,526 patients with biological SAVR (CABG 39.7%) and 3,677 patients with mechanical SAVR (CABG 23.8%). Reintervention rates at 1-year, 3-years and 5-years were comparable across type of SAVR, and generally low (Figure). Accounting for the competing risk of death, reintervention rates at 5-years were 1.4% (95% CI 1.1–1.6) for biological SAVR and 1.5% (95% CI 1.1–1.9) for mechanical SAVR, respectively. In age-stratified competing risk analyses, we observed the highest rates in patients aged 40–59 years (4% [95% CI 1.8–6] at 5 years for biological SAVR, and 2% [95% CI 1.3–3] for mechanical SAVR). Following biological SAVR, annual echocardiographic controls would yield a total of 34,516 scans in our population in the first 5 years following surgery. This contrasts to a total of 66 reinterventions following biological SAVR in our population between years 1–5 of which the majority was preceded by a hospital admission with a primary diagnosis of endocarditis within the last 90 days prior to the reintervention; which are unlikely to have been diagnosed at the annual assessment scan.

Conclusion(s)

In this nationwide study, reintervention rates following biological or mechanical SAVR were very low within the first five years after surgery suggesting a discrepancy between ESC recommendations on echocardiographic controls following SAVR, the benefit for patients, and the associated resource burden on the health care system.

Figure 1

Funding Acknowledgement

Type of funding source: None

Detection and molecular characterization of chicken astrovirus associated with chicks that have an unusual condition known as "white chicks" in Brazil

Chicken astrovirus (CAstV) is one of many viruses related to enteric diseases in poultry that are associated with Runting-Stunting Syndrome (RSS), which affects young chickens. CAstV was also recently associated with an unusual condition in chicks called “white chicks.” Some hatcheries in certain states of Brazil have reported several incubation problems, mortality, and the presence of chicks with white plumages over the past several months. These chicks were termed locally as “white chicks.” The present work investigated 30 chicks with this unusual condition using a multidisciplinary approach. Postmortem examination of each chick showed enlarged livers and intestines that were full of liquid and gas (30/30). The pancreas, kidneys, and spleen were pale (30/30). The other organs did not show any macroscopic alterations. CAstV, chicken parvovirus (ChPV), avian nephritis virus (ANV), avian rotavirus (ARtV), avian reovirus (AReoV), infectious bronchitis virus (IBV), and fowl adenovirus group I (FAdV-1) were tested in the intestines, pancreas, proventriculus, gizzard, liver, spleen, bursa, kidneys, thymus, lung, heart, brain, and yolk sac in each chick. All organs and yolk sacs were positive for CAstV in different titres and negative for the other tested viruses. The partial molecular characterization of the ORF 1b gene of CAstV using 28 sequences revealed a high similarity of the nucleotides and amino acids with sequences of CAstV from North America, Europe, and Asia, and our CAstV sequences clustered into a unique group that was separate from the other sequences. These results demonstrated that CAstV was associated with the white chick condition in Brazil. The virus was distributed in most organs, including the brain and yolk sac. These results suggest that the virus could be transmitted vertically. The molecular characterization also revealed that the CAstV associated with white chick condition was molecularly related to other CAstV sequences found worldwide.

Molecular detection of chicken parvovirus in broilers with enteric disorders presenting curving of duodenal loop, pancreatic atrophy, and mesenteritis

Enteric disorders are an important cause of economic losses in broiler chickens worldwide. Several agents have been associated with enteric problems, such as viruses, bacteria, and parasites. In this study, broiler chickens showing signs of enteric disorders were subjected to molecular diagnosis for several viral agents and also for pathological examination for elucidating this problem. Thus, the chickens were screened for avian nephritis virus (ANV), chicken astrovirus (CAstV), avian rotavirus (ArtV), avian reovirus (AReoV), infectious bronchitis virus (IBV), fowl adenovirus group I (FAdV-1), and chicken parvovirus (ChPV). Postmortem examinations revealed a curving of the duodenal loop (J-like appearance) and intestines filled with liquid and gaseous content. Histopathological analysis of the duodenal loop showed pancreatic atrophy, acute mesenteritis, and enteritis. PCR results showed that ChPV was the sole viral agent detected in samples with lesions such as the curved duodenal loop and pancreatic atrophy. Molecular characterization of the nucleotide and deduced amino acid sequences revealed a high similarity with other strains of ChPV from Brazil, Canada, United States, Europe, and Asia. These findings suggest an association between ChPV and the development of enteritis, pancreatitis, and pancreatic atrophy, which may lead to curling of the duodenal loop. Together, these alterations may disrupt the normal functioning of the digestive system, diminishing digestion and the absorption of dietary nutrients and consequently leading to reduced weight gain, flock impairment, dwarfism, and an elevated feed conversion rate.

A Mayan founder mutation is a common cause of deafness in Guatemala

Over 5% of the world's population has varying degrees of hearing loss. Mutations in GJB2 are the most common cause of autosomal recessive non-syndromic hearing loss (ARNHL) in many populations. The frequency and type of mutations are influenced by ethnicity. Guatemala is a multi-ethnic country with four major populations: Maya, Ladino, Xinca, and Garifuna. To determine the mutation profile of GJB2 in a ARNHL population from Guatemala, we sequenced both exons of GJB2 in 133 unrelated families. A total of six pathogenic variants were detected. The most frequent pathogenic variant is c.131G>A (p.Trp44*) detected in 21 of 266 alleles. We show that c.131G>A is associated with a conserved haplotype in Guatemala suggesting a single founder. The majority of Mayan population lives in the west region of the country from where all c.131G>A carriers originated. Further analysis of genome-wide variation of individuals carrying the c.131G>A mutation compared with those of Native American, European, and African populations shows a close match with the Mayan population.

Evaluation of the role of angiogenic factors in the pathogenesis of schistosomiasis

Schistosomiasis is one disease produced by helminths, which affect many people in tropical areas. Granuloma formation is the main mechanism involved in the pathogenesis of this disease. Experimental studies have demonstrated angiogenesis (blood vessels formation from pre-existing vessels) in the initial phase of granuloma formation. In the present work, VEGF (vascular endothelial growth factor) levels were analyzed in sera from people diagnosed with different helminthic infections. Patients with schistosomiasis and filariasis had significantly high VEGF levels in compared with healthy people and patients diagnosed with hookworms. In addition, the effects of angiogenesis inhibition using anti-angiogenic factors (endostatin) were evaluated in a schistosomiasis murine model. A lesion decrease was observed in mice infected with Schistosoma mansoni and treated with endostatin. Finally, mechanisms of angiogenesis induction were studied and observed that cercariae antigens stimulated the angiogenic factors by host alveolar macrophages.

Seroprevalence of Coxiella burnetii in domestic ruminants in Gran Canaria Island, Spain

Coxiella burnetii is the causative agent of Q fever, a zoonosis with worldwide occurrence. In the Canary Islands, the overall seroprevalence in humans has been estimated to be 21.5%. Gran Canaria island concentrates the highest ruminant population in the archipelago and the prevalence of the human infection is 23.5%. To evaluate the seroprevalence in livestock and the affected areas in Gran Canaria island, a total of 1249 ruminants were randomly selected for this study (733 goats, 369 sheep and 147 cattle). The samples were evaluated using an indirect ELISA Kit. The results showed seroprevalences of 60.4%, 31.7% and 12.2% in goats, sheep and cattle, respectively. Based on these results, Q fever could be considered as endemic in Gran Canaria island. Sanitary measures should be taken at the farm level to minimize the risk of exposure of C. burnetii to humans.

[Antiparasitic drugs. Review of the useful drugs in the treatment of classic and emergent parasitic diseases]

INTRODUCTION

In the 10 last years, the increase of international travels and immigration from low income countries to Spain was related with an increased of prevalence of parasitic diseases.

SOURCE

Critical review of the literature.

STRUCTURE

Firstly, several general considerations were made on the antiparasitic drugs revised in this paper. Chemical structures and mechanisms of action of the main drugs with antiparasitic effect were considered in the second part of the review. Further, antiparasitic spectrum of selected drugs, main pharmacokinetical characteristics, usual posology, possible side effects and contraindications were detailed. Finally, some practical aspects, such as interactions and the methods for practical obtention of these drugs are indicated. This information is relevant because in Spain many anti-parasitic drugs may be obtained using non conventional methods.

CONCLUSION

In Spain, the increase of parasitic diseases necessitates an update on antiparasitics drugs for their treatment.

A new PCR-based approach for the specific amplification of DNA from different Schistosoma species applicable to human urine samples

Currently available methods for the diagnosis of human schistosomiasis often lack enough sensitivity and specificity. Recently, several authors have developed more specific and sensitive diagnostic methods, mainly based on the polymerase chain reaction (PCR) technique. Nevertheless, these have been only applied for the diagnosis of 1 out of 4 Schistosoma species affecting man (S. mansoni). Additionally, application of specific PCR has been exclusively used for blood or faecal patients' samples. Here, we develop a new, high sensitive PCR approach that allows the genus- and species-specific amplification of the main 4 Schistosoma species causing disease in man plus S. bovis. We further successfully apply this technique for the detection of parasite DNA in easy-to-handle urine samples from patients with schistosomiasis. With these samples, we have found 94.4% sensitivity and 99.9% specificity when applying a genus-specific (Schistosoma spp.) primer pair, and 100% sensitivity and 98.9% specificity in a species-specific (S. mansoni) PCR.

Environmental health assessment of deltamethrin in a malarious area of Mexico: environmental persistence, toxicokinetics, and genotoxicity in exposed children

We reported previously that children are exposed to deltamethrin in malarious areas. In the present work we explored the levels of this insecticide in soil samples and also obtained relevant toxicokinetic data of deltamethrin in exposed children. Results show that, after spraying, indoor levels of deltamethrin in soil samples were higher than outdoor levels. The mean half-life estimated with these data was 15.5 days for outdoor samples and 15.4 days for indoor samples. Children's exposure to deltamethrin was assessed using as biomarkers the urinary concentrations of the metabolites 3-phenoxybenzoic acid (3-PBA) and cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (Br2CA). The mean level of both biomarkers reached a peak within the first 24 hr postexposure; 6 months after the initial exposure, urinary levels of 3-PBA and Br2CA were found at levels observed before exposure. Approximately 91% of the total 3-PBA or Br2CA was excreted during the first 3 days after exposure. Therefore, we estimated a half-life for this period, the values for 3-PBA and Br2CA being almost identical (13.5 vs. 14.5 hr). Finally, considering reports about the genotoxicity of deltamethrin, we assessed DNA damage in children before and 24 hr after indoor spraying of deltamethrin; we found no differences in the comet assay end points. In conclusion, we observed exposure to deltamethrin in children, but we did not find any relationship between soil concentrations of deltamethrin and urinary levels of the metabolites. At least for genotoxicity, the exposed children appeared not to be at risk.

Utility of Schistosoma bovis adult worm antigens for diagnosis of human schistosomiasis by enzyme-linked immunosorbent assay and electroimmunotransfer blot techniques

Immunodiagnostic methods based on the detection of antibodies continue to be the most effective and practical methods for the diagnosis of imported schistosomiasis. Schistosoma bovis is a species whose final natural hosts are bovines, ovines, caprines, and small wild ruminants. Different studies have demonstrated the analogies existing between S. bovis and other Schistosoma species which affect humans. The objective of this work was to evaluate the utility of S. bovis adult worm antigens (AWA) for the diagnosis of imported human schistosomiasis by enzyme-linked immunosorbent assay (ELISA) and electroimmunotransfer blotting (EITB) techniques. By detecting eggs, the ELISA for S. bovis AWA was able to definitively detect imported cases with a sensitivity of 94%. The specificity of the ELISA for S. bovis AWA was 97%. There were no differences between the results of the S. bovis AWA ELISA for patients infected with Schistosoma mansoni and those infected with Schistosoma haematobium. The EITB technique showed bands of 85, 37, and 20 kDa, which are characteristic of infections with Schistosoma spp. Specific bands to indicate infection by different species of Schistosoma have not been detected. The combined use of the ELISA for S. bovis AWA and EITB increased the global sensitivity of the study to 97%. Our findings suggest that the ELISA for S. bovis AWA is a useful test for the immunodiagnosis of imported schistosomiasis and that EITB for detecting S. bovis AWA permits the confirmation of diagnosis when the ELISA for S. bovis AWA is positive.

[Eoshinophilia: a practical approach]

In this first part of this paper we review the definition of eosinophilia and their classification according to the degree of elevation of eosinophils/microL. Aetiological factors related with eosinophilia were described in three groups of patients: a). autochthonous non-infected by HIV; b). HIV-infected; and c). arrived from tropical countries (imported eosinophilia). We included an algorithmic approach to the diagnosis, including the diagnostic studies that should be performed in patients with or without organ involvement. Pathological consequences of eosinophilia are indicated in the next part of the paper. Finally, therapeutical options used in patients with eosinophilia are reviewed, with an special emphasis on antihelminthic therapies and the management of the hypereosinophilic syndromes.

[Streptococcus pyogenes: penicillin and erythromycin susceptibility in the cities of Neuquen and Cipolletti]

Penicillin resistance has not yet been detected in Streptococcus pyogenes. However macrolide-resistant streptococci have emerged in several countries. Only low rates of erythromycin-resistant S. pyogenes were reported in Argentina, with the exception of a 11.1% observed in Mendoza. The aim of the present study was to determine the susceptibility to penicillin and to erythromycin of 251 consecutive clinically-significant isolates of S. pyogenes obtained from four centers of Cipolletti and Neuquén during the period April-December 1998. The double disk test with erythromycin and clindamycin disks was employed as a screening method to detect ERY-resistant streptococci and to determine the phenotype of macrolide resistance. Disk diffusion was also employed for determining penicillin susceptibility. Macrolide-resistant isolates were also tested for penicillin, ceftriaxone, erythromycin, clindamycin and azithromycin susceptibility by the agar dilution method. Additionally they were also tested for erythromycin susceptibility by E-test (AB Biodisk, Solna, Sweden). All streptococci studied were susceptible to penicillin and thirty of them (12.0%) were resistant to erythromycin. All these resistant isolates were also resistant to azithromycin but susceptible to ceftriaxone and clindamycin. They showed the phenotype M (probably efflux-mediated mechanism) and the MICs of erythromycin ranged between 8 and 16 micrograms/ml. According to these results we conclude that in spite of universal susceptibility to penicillin in S. pyogenes, macrolide resistance is a matter of concern in Neuquén and Cipolletti. At least in those cities it appears to be necessary to routinely perform macrolide susceptibility tests in beta-hemolytic streptococci.

A homogeneous method to measure aminoacyl-tRNA synthetase aminoacylation activity using scintillation proximity assay technology

A new method to measure the aminoacylation of tRNA based upon the use of the scintillation proximity assay (SPA) technology has been developed. The assay detects incorporation of radiolabeled amino acids into cognate tRNA, catalyzed by a specific aminoacyl-tRNA synthetase (aaRS). Under acidic conditions, uncoated yttrium silicate SPA beads were found to bind tRNA aggregates, while the radiolabeled amino acid substrate remains in solution, resulting in good signal discrimination of these two species in the absence of any separation steps. The usefulness of this approach was demonstrated by measurement of steady-state kinetic constants and inhibitor binding constants for a range of aaRS enzymes in comparison with data from standard, trichloroacetic acid-precipitation-based assays. In all cases, the data were quantitatively comparable. Although the radioisotopic counting efficiency of the SPA method was less than that of standard liquid scintillation counting, the statistical performance (i.e., signal to background, variability, stability) of the SPA assays was at least equivalent to the separation-based methods. The assay was also shown to work well in miniaturized 384-well microtiter plate formats, resulting in considerable reagent savings. In summary, a new method to characterize aaRS activity is described that is faster and more amenable to high-throughput screening than traditional methods.

Enhanced responses to Mycobacterium tuberculosis antigens by human alveolar lymphocytes during active pulmonary tuberculosis

Responses to mycobacterial and nonmycobacterial antigens were examined in bronchoalveolar cells (BAC) and peripheral blood mononuclear cells (PBMC) from patients with active pulmonary tuberculosis (n=16) and healthy subjects (n=23). DNA synthesis in BAC (but not PBMC) from tuberculosis patients was significantly increased in response to the mycobacterial antigens purified protein derivative (PPD), antigen 85, and mannose-capped lipoarabinomannan but not to nonmycobacterial antigens. The response to PPD was also increased in enriched alveolar lymphocytes from tuberculosis patients (P<.05). The frequency of interferon-gamma but not interleukin-4- or -10-producing cells by ELISAspot was increased in PPD-stimulated BAC from patients with tuberculosis (P<.05). Accessory function of alveolar macrophages for T lymphocyte responses was similar and suppressive activity was variably decreased in tuberculosis patients. Thus, there is compartmentalization of mycobacterial antigen-specific lymphocytes to the lungs during active tuberculosis that on challenge produce a Th1-type cytokine host response.

[Colorectal cancer: its clinical picture and survival]

Retrospectively collected information on 77 patients who had undergone resection for colorectal cancer at Belén Hospital, Trujillo, Perú, from 1966 to 1993, was analyzed to establish their clinical features and the importance of both clinical and pathological factors affecting outcome. Common presenting features in right colon cancer were abdominal pain, pallor, and palpable mass; in left colon cancer were symptoms of obstruction, and in rectal carcinoma predominated bleeding. The diagnostic accuracy of barium enema (n = 25) and proctosigmoidoscopy (n = 18) was 72 and 100% respectively. In 54.5% (n = 42) curative resection and in 45.5% (n = 35) palliative resection was performed The surgical procedures performed were right hemicolectomy (n = 29), transverse colectomy (n = 6), left hemicolectomy (n = 11), sigmoid resection (n = 14), low anterior resection (n = 5), and abdominoperineal resection of the rectum (n = 12). The total perioperative mortality rate was 18%. The 5 year survival rate in this series was 28% (53% for curative resection and 0% for palliative resection). An univariate analysis of survival time using long-rank test revealed that presence of bowel obstruction or perforation, macroscopic appearance, tumor size, depth of invasion, lymph node status, number of lymph node metastasis, distant metastasis, and clinical stage had and individual prognostic significance. Age, sex, length of disease, serum hemoglobin level, blood transfusions, location of tumor, histologic type, and tumor grade did not affect the prognosis. Improvement in the survival probably depends on development of better adjuvant therapy in association with surgery.

[Transesophageal echocardiography: experience with the first 500 consecutive cases]

The results of all the transesophageal echocardiographies (TEE) performed between June 1989 and February 1992 are analyzed. Five hundred patients (240 male) with a median age of 57 years (range 13-88) were examined; during the same period, 5180 transthoracic echocardiographies were performed. TEE were requested for the following reasons: valvular prosthesis disfunction in 132 patients, rheumatic valvulopathy in 103, search for embolic origins in 97, study of congenital cardiopathies in 48, bacterial endocarditis in 35, aortic dissection in 25 and miscellaneous in 78. Among congenital cardiopathies there were 29 cases of interauricular communication and among miscellaneous cases, 9 patients with cardiac tumors. No major complications occurred. The imaging quality of this technique renders it specially important in the study of prosthesis disfunction, mitral valve analysis before valvuloplasty, detection of cardiac origins of emboli and infective endocarditis complications and anatomical and dynamic analysis of aortic dissection. It is concluded that TEE is a safe technique that provides high quality images and visualizes segments of the heart and great vessels formerly inaccessible with transthoracic echocardiography. It has enlarged the diagnostic capacity of echocardiography and improved the support of therapeutic decisions.

[Mitral valve prolapse and cerebral ischemia]

We report on 10 patients suffering from cerebral ischemic episodes in whom mitral valve prolapse was diagnosed. Neurologic assessment included computerized tomography and angiographic study. In one case, the angiographic study revealed the presence of intracranial vasculitis and one woman was taking the contraceptive pill. The diagnosis of mitral valve prolapse was established on the basis of clinical grounds and electrocardiographic, Doppler study, Holter monitoring and two-dimensional echocardiographic signs. Our findings confirm that mitral valve prolapse is an etiologic factor to be considered in young adults with cerebral ischemia, although mitral valve prolapse does not exclude the possibility of other etiopathogenic conditions occurring.

Acute glomerulonephritis in children. An evolutive morphologic and immunologic study of the glomerular inflammation

This study deals with 80 children showing a clinically typical acute nephritic syndrome with proteinuria and/or hematuria, edema, and hypertension. Their ages ranged between 2 years 5 months and 16 years; 36 cases were female. In 73 cases a streptococcal infection was demonstrated; the remaining 7 cases did not show morphologic differences with the former. No previous renal disease nor familial history of nephropathies were elicited. In every case a renal biopsy was obtained in the first 60 days of clinical disease; in 46 cases a second renal biopsy was obtained sometime between 6 and 45 months since the beginning of the disease. In 3 cases the renal tissue was considered to be normal by light microscopy, immunofluorescence and electron microscopy in both the first and second biopsies. These 3 patients were not considered as cases of morphologic acute glomerulonephritis in spite of showing a typical clinical picture and they are not included in the evaluation of the glomerular inflammatory evolution. In all the remaining 77 cases C3 granular and segmentary intramembranous and mesangial dense deposits were found in the first biopsy. The second biopsy showed morphologic and immunologic normalization in 27% of the cases, slight lesions in 56% and an increase in severity in 17% of the cases.

Clinical and morphological recovery between two episodes of acute glomerulonephritis: a light and electron microscopic study with immunofluorescence

A 4 year-old girl presented with 2 episodes of acute glomerulonephritis with clinical and morphological recovery between them. Both episodes were preceded by impetigo. The first and third renal biopsies showed glomerulitis with diffuse dense deposits in the mesangium, segmentary intramembranous dense deposits, atypical "humps" and granular C3. The second biopsy, taken between episodes, was considered to be normal. Two years and 5 months after the second episode the clinical evaluation and laboratory tests were normal.

[Renal function in normal and malnourished children given different doses of vasopressin in continuous infusion]

The effects of vasopressin administered by continuous infusion (0.75 and 0.5 mU/m2/minutes) was studied in two groups of three normal and two groups of 5 and 8 malnourished children given 0.5 and 0.3 mU/m2/minute. The following parameters were analyzed: urine volume, osmolality, water reabsorption, PAH, urea and inulin clearances, Na and K urinary excretion. Malnourished children had a urine volume 3 to 5 times higher than the normal groups. Vasopressin increased urine volume initially, but a mild antidiuretic effect followed in the normal groups. In malnourished children with a high CH2O, antidiuresis showed quite important figures with vasopressin. A transient fall in PAH and inulin clearances was observed with vasopressin in both malnourished groups with a mild drop in the normal group. Natriuresis with a higher % of the filtered sodium excretion was observed in the malnourished groups and in normal children with 0.5 mU of vasopressin. These results show that vasopressin had similar effects, but at a different level in the normal and malnourished children that we studied.