939 resultados para Exponential versus non-exponential decay
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This clinical study prospectively evaluated the healing outcome 1 year after apical surgery in relation to bony crypt dimensions measured intraoperatively. The study cohort included 183 teeth in an equal number of patients. For statistical analysis, results were dichotomized (healed versus non-healed cases). The overall success rate was 83% (healed cases). Healing outcome was not significantly related to the level and height of the facial bone plate. In contrast, a significant difference was found for the mean size of the bony crypt when healed cases (395 mm(3)) were compared with non-healed cases (554 mm(3)). In addition, healed cases had a significantly shorter mean distance (4.30 mm) from the facial bone surface to the root canal (horizontal access) compared with non-healed cases (5.13 mm). With logistic regression, however, the only parameter found to be significantly related to healing outcome was the length of the access window to the bony crypt.
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The intent of the work presented in this thesis is to show that relativistic perturbations should be considered in the same manner as well known perturbations currently taken into account in planet-satellite systems. It is also the aim of this research to show that relativistic perturbations are comparable to standard perturbations in speciffc force magnitude and effects. This work would have been regarded as little more then a curiosity to most engineers until recent advancements in space propulsion methods { e.g. the creation of a artiffcial neutron stars, light sails, and continuous propulsion techniques. These cutting-edge technologies have the potential to thrust the human race into interstellar, and hopefully intergalactic, travel in the not so distant future. The relativistic perturbations were simulated on two orbit cases: (1) a general orbit and (2) a Molniya type orbit. The simulations were completed using Matlab's ODE45 integration scheme. The methods used to organize, execute, and analyze these simulations are explained in detail. The results of the simulations are presented in graphical and statistical form. The simulation data reveals that the speciffc forces that arise from the relativistic perturbations do manifest as variations in the classical orbital elements. It is also apparent from the simulated data that the speciffc forces do exhibit similar magnitudes and effects that materialize from commonly considered perturbations that are used in trajectory design, optimization, and maintenance. Due to the similarities in behavior of relativistic versus non-relativistic perturbations, a case is made for the development of a fully relativistic formulation for the trajectory design and trajectory optimization problems. This new framework would afford the possibility of illuminating new more optimal solutions to the aforementioned problems that do not arise in current formulations. This type of reformulation has already showed promise when the previously unknown Space Superhighways arose as a optimal solution when classical astrodynamics was reformulated using geometric mechanics.
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Background: Available studies vary in their estimated prevalence of attention deficit/hyperactivity disor-der (ADHD) in substance use disorder (SUD) patients, ranging from 2 to 83%. A better understanding ofthe possible reasons for this variability and the effect of the change from DSM-IV to DSM-5 is needed.Methods: A two stage international multi-center, cross-sectional study in 10 countries, among patientsform inpatient and outpatient addiction treatment centers for alcohol and/or drug use disorder patients. Atotal of 3558 treatment seeking SUD patients were screened for adult ADHD. A subsample of 1276 subjects,both screen positive and screen negative patients, participated in a structured diagnostic interview. 5AdultsResults: Prevalence of DSM-IV and DSM-5 adult ADHD varied for DSM-IV from 5.4% (CI 95%: 2.4–8.3) forHungary to 31.3% (CI 95%:25.2–37.5) for Norway and for DSM-5 from 7.6% (CI 95%: 4.1–11.1) for Hungary to32.6% (CI 95%: 26.4–38.8) for Norway. Using the same assessment procedures in all countries and centersresulted in substantial reduction of the variability in the prevalence of adult ADHD reported in previousstudies among SUD patients (2–83% → 5.4–31.3%). The remaining variability was partly explained byprimary substance of abuse and by country (Nordic versus non-Nordic countries). Prevalence estimatesfor DSM-5 were slightly higher than for DSM-IV.Conclusions: Given the generally high prevalence of adult ADHD, all treatment seeking SUD patientsshould be screened and, after a confirmed diagnosis, treated for ADHD since the literature indicates poorprognoses of SUD in treatment seeking SUD patients with ADHD.
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Dichelobacter nodosus, the etiological agent of ovine footrot, exists both as virulent and as benign strains, which differ in virulence mainly due to subtle differences in the three subtilisin-like proteases AprV2, AprV5 and BprV found in virulent, and AprB2, AprB5 and BprB in benign strains of D. nodosus. Our objective was a molecular genetic epidemiological analysis of the genes of these proteases by direct sequence analysis from clinical material of sheep from herds with and without history of footrot from 4 different European countries. The data reveal the two proteases known as virulent AprV2 and benign AprB2 to correlate fully to the clinical status of the individuals or the footrot history of the herd. In samples taken from affected herds, the aprV2 gene was found as a single allele whereas in samples from unaffected herds several alleles with minor modifications of the aprB2 gene were detected. The different alleles of aprB2 were related to the herds. The aprV5 and aprB5 genes were found in the form of several alleles scattered without distinction between affected and non-affected herds. However, all different alleles of aprV5 and aprB5 encode the same amino acid sequences, indicating the existence of a single protease isoenzyme 5 in both benign and virulent strains. The genes of the basic proteases BprV and BprB also exist as various alleles. However, differences found in samples from affected versus non-affected herds do not reflect the currently known epitopes that are attributed to differences in biochemical activity. The data of the study confirm the prominent role of AprV2 in the virulence of D. nodosus and shed a new light on the presence of the other protease genes and their allelic variants in clinical samples.
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Human-induced forest modification can alter parasite-host interactions and might change the persistence of host populations. We captured individuals of two widespread European passerines (Fringilla coelebs and Sylvia atricapilla) in southwestern Germany to disentangle the associations of forest types and parasitism by haemosporidian parasites on the body condition of birds. We compared parasite prevalence and parasite intensity, fluctuating asymmetries, leukocyte numbers, and the heterophil to lymphocyte ratio (H/L-ratio) among individuals from beech, mixed-deciduous and spruce forest stands. Based on the biology of bird species, we expected to find fewer infected individuals in beech or mixed-deciduous than in spruce forest stands. We found the highest parasite prevalence and intensity in beech forests for F. coelebs. Although, we found the highest prevalence in spruce forests for S. atricapilla, the highest intensity was detected in beech forests, partially supporting our hypothesis. Other body condition or health status metrics, such as the heterophil to lymphocyte ratio (H/L-ratio), revealed only slight differences between bird populations inhabiting the three different forest types, with the highest values in spruce for F. coelebs and in mixed-deciduous forests for S. atricapilla. A comparison of parasitized versus non-parasitized individuals suggests that parasite infection increased the immune response of a bird, which was detectable as high H/L-ratio. Higher infections with blood parasites for S. atricapilla in spruce forest indicate that this forest type might be a less suitable habitat than beech and mixed-deciduous forests, whereas beech forests seem to be a suboptimal habitat regarding parasitism for F. coelebs.
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OBJECTIVES This study sought to evaluate the relationship between fibrosis imaged by delayed-enhancement (DE) magnetic resonance imaging (MRI) and atrial electrograms (Egms) in persistent atrial fibrillation (AF). BACKGROUND Atrial fractionated Egms are strongly related to slow anisotropic conduction. Their relationship to atrial fibrosis has not yet been investigated. METHODS Atrial high-resolution MRI of 18 patients with persistent AF (11 long-lasting persistent AF) was registered with mapping geometry (NavX electro-anatomical system (version 8.0, St. Jude Medical, St. Paul, Minnesota)). DE areas were categorized as dense or patchy, depending on their DE content. Left atrial Egms during AF were acquired using a high-density, 20-pole catheter (514 ± 77 sites/map). Fractionation, organization/regularity, local mean cycle length (CL), and voltage were analyzed with regard to DE. RESULTS Patients with long-lasting persistent versus persistent AF had larger left atrial (LA) surface area (134 ± 38 cm(2) vs. 98 ± 9 cm(2), p = 0.02), a higher amount of atrial DE (70 ± 16 cm(2) vs. 49 ± 10 cm(2), p = 0.01), more complex fractionated atrial Egm (CFAE) extent (54 ± 16 cm(2) vs. 28 ± 15 cm(2), p = 0.02), and a shorter baseline AF CL (147 ± 10 ms vs. 182 ± 14 ms, p = 0.01). Continuous CFAE (CFEmean [NavX algorithm that quantifies Egm fractionation] <80 ms) occupied 38 ± 19% of total LA surface area. Dense DE was detected at the left posterior left atrium. In contrast, the right posterior left atrium contained predominantly patchy DE. Most CFAE (48 ± 14%) occurred at non-DE LA sites, followed by 41 ± 12% CFAE at patchy DE and 11 ± 6% at dense DE regions (p = 0.005 and p = 0.008, respectively); 19 ± 6% CFAE sites occurred at border zones of dense DE. Egms were less fractionated, with longer CL and lower voltage at dense DE versus non-DE regions: CFEmean: 97 ms versus 76 ms, p < 0.0001; local CL: 153 ms versus 143 ms, p < 0.0001; mean voltage: 0.63 mV versus 0.86 mV, p < 0.0001. CONCLUSIONS Atrial fibrosis as defined by DE MRI is associated with slower and more organized electrical activity but with lower voltage than healthy atrial areas. Ninety percent of continuous CFAE sites occur at non-DE and patchy DE LA sites. These findings are important when choosing the ablation strategy in persistent AF.
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Cichlid fishes have evolved tremendous morphological and behavioral diversity in the waters of East Africa. Within each of the Great Lakes Tanganyika, Malawi, and Victoria, the phenomena of hybridization and retention of ancestral polymorphism explain allele sharing across species. Here, we explore the sharing of single nucleotide polymorphisms (SNPs) between the major East African cichlid assemblages. A set of approximately 200 genic and nongenic SNPs was ascertained in five Lake Malawi species and genotyped in a diverse collection of 160 species from across Africa. We observed segregating polymorphism outside of the Malawi lineage for more than 50% of these loci; this holds similarly for genic versus nongenic SNPs, as well as for SNPs at putative CpG versus non-CpG sites. Bayesian and principal component analyses of genetic structure in the data demonstrate that the Lake Malawi endemic flock is not monophyletic and that river species have likely contributed significantly to Malawi genomes. Coalescent simulations support the hypothesis that river cichlids have transported polymorphism between lake assemblages. We observed strong genetic differentiation between Malawi lineages for approximately 8% of loci, with contributions from both genic and nongenic SNPs. Notably, more than half of these outlier loci between Malawi groups are polymorphic outside of the lake. Cichlid fishes have evolved diversity in Lake Malawi as new mutations combined with standing genetic variation shared across East Africa.
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Human papilloma virus (HPV) infection of the uterine cervix is linked to the pathogenesis of cervical cancer. Preclinical in vitro and in vivo studies using HPV-containing human cervical carcinoma cell lines have shown that the mammalian target of rapamycin (mTOR) inhibitor, rapamycin, and epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor, erlotinib, can induce growth delay of xenografts. Activation of Akt and mTOR are also observed in cervical squamous cell carcinoma and, the expression of phosphorylated mTOR was reported to serve as a marker to predict response to chemotherapy and survival of cervical cancer patients. Therefore, we investigated: a) the expression level of EGFR in cervical squamous cell carcinoma (SCC) and high-grade squamous intraepithelial lesions (HSIL) versus non-neoplastic cervical squamous epithelium; b) the state of activation of the mTOR pathway in these same tissues; and c) any impact of these signal transduction molecules on cell cycle. Formalin-fixed paraffin-embedded tissue microarray blocks containing 20 samples each of normal cervix, HSIL and invasive SCC, derived from a total of 60 cases of cervical biopsies and cervical conizations were examined. Immunohistochemistry was utilized to detect the following antigens: EGFR; mTOR pathway markers, phosphorylated (p)-mTOR (Ser2448) and p-p70S6K (Thr389); and cell cycle associated proteins, Ki-67 and S phase kinase-associated protein (Skp)2. Protein compartmentalization and expression were quantified in regard to proportion (0-100%) and intensity (0-3+). Mitotic index (MI) was also assessed. An expression index (EI) for pmTOR, p-p70S6K and EGFR, respectively was calculated by taking the product of intensity score and proportion of positively staining cells. We found that plasmalemmal EGFR expression was limited to the basal/parabasal cells (2-3+, EI = 67) in normal cervical epithelium (NL), but was diffusely positive in all HSIL (EI = 237) and SCC (EI 226). The pattern of cytoplasmic p-mTOR and nuclear p-p70S6K expression was similar to that of EGFR; all showed a significantly increased EI in HSIL/SCC versus NL (p<0.02). Nuclear translocation of p-mTOR was observed in all SCC lesions (EI = 202) and was significantly increased versus both HSIL (EI = 89) and NL (EI = 54) with p<0.015 and p<0.0001, respectively. Concomitant increases in MI and proportion of nuclear Ki-67 and Skp2 expression were noted in HSIL and SCC. In conclusion, morphoproteomic analysis reveals constitutive activation and overexpression of the mTOR pathway in HSIL and SCC as evidenced by: increased nuclear translocation of pmTOR and p-p70S6K, phosphorylated at putative sites of activation, Ser2448 and Thr389, respectively; correlative overexpression of the upstream signal transducer, EGFR, and increases in cell cycle correlates, Skp2 and mitotic indices. These results suggest that the mTOR pathway plays a key role in cervical carcinogenesis and targeted therapies may be developed for SCC as well as its precursor lesion, HSIL.
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Purpose The sedimentation sign (SedSign) has been shown to discriminate well between selected patients with and without lumbar spinal stenosis (LSS). The purpose of this study was to compare the pressure values associated with LSS versus non-LSS and discuss whether a positive SedSign may be related to increased epidural pressure at the level of the stenosis. Methods We measured the intraoperative epidural pressure in five patients without LSS and a negative SedSign, and in five patients with LSS and a positive SedSign using a Codman TM catheter in prone position under radioscopy. Results Patients with a negative SedSign had a median epidural pressure of 9 mmHg independent of the measurement location. Breath and pulse-synchronous waves accounted for 1–3 mmHg. In patients with monosegmental LSS and a positive SedSign, the epidural pressure above and below the stenosis was similar (median 8–9 mmHg). At the level of the stenosis the median epidural pressure was 22 mmHg. A breath and pulse-synchronous wave was present cranial to the stenosis, but absent below. These findings were independent of the cross-sectional area of the spinal canal at the level of the stenosis. Conclusions Patients with LSS have an increased epidural pressure at the level of the stenosis and altered pressure wave characteristics below. We argue that the absence of sedimentation of lumbar nerve roots to the dorsal part of the dural sac in supine position may be due to tethering of affected nerve roots at the level of the stenosis.
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The purpose of this research is to examine the relative profitability of the firm within the nursing facility industry in Texas. An examination is made of the variables expected to affect profitability and of importance to the design and implementation of regulatory policy. To facilitate this inquiry, specific questions addressed are: (1) Do differences in ownership form affect profitability (defined as operating income before fixed costs)? (2) What impact does regional location have on profitability? (3) Do patient case-mix and access to care by Medicaid patients differ between proprietary and non-profit firms and facilities located in urban versus rural regions, and what association exists between these variables and profitability? (4) Are economies of scale present in the nursing home industry? (5) Do nursing facilities operate in a competitive output market characterized by the inability of a single firm to exhibit influence over market price?^ Prior studies have principally employed a cost function to assess efficiency differences between classifications of nursing facilities. The inherent weakness in this approach is that it only considers technical efficiency. Not both technical and price efficiency which are the two components of overall economic efficiency. One firm is more technically efficient compared to another if it is able to produce a given quantity of output at the least possible costs. Price efficiency means that scarce resources are being directed towards their most valued use. Assuming similar prices in both input and output markets, differences in overall economic efficiency between firm classes are assessed through profitability, hence a profit function.^ Using the framework of the profit function, data from 1990 Medicaid Costs Reports for Texas, and the analytic technique of Ordinary Least Squares Regression, the findings of the study indicated (1) similar profitability between nursing facilities organized as for-profit versus non-profit and located in urban versus rural regions, (2) an inverse association between both payor-mix and patient case-mix with profitability, (3) strong evidence for the presence of scale economies, and (4) existence of a competitive market structure. The paper concludes with implications regarding reimbursement methodology and construction moratorium policies in Texas. ^
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Obesity and related chronic diseases represent a tremendous public health burden among Mexican Americans, a young and rapidly-expanding population. This study investigated the impact of variation within eight candidate obesity genes, which include leptin (LEP), leptin receptor (LEPR), neuropeptide Y (NPY), NPYY1 receptor (NPYY1), glucagon-like peptide-1 (GLP-1), GLP-1 receptor (GLP1R), beta-3 adrenergic receptor (β3AR), and uncoupling protein (UCP1), on variation in human obesity status and/or quantitative traits related to obesity in Mexican Americans from Starr County, Texas. The Trp64Arg polymorphism within β3AR was typed in 820 random individuals and 240 pedigrees (N = 2,044). The Arg allele frequency was significantly greater in obese versus non-obese individuals (0.20 versus 0. 15, respectively). In addition, within the random sample, the Arg allele was associated with significantly greater body weight (p = 0.031) and body mass index (BMI, p = 0.008) than the Trp allele. In the family sample, the Trp64Arg locus was also linked to percent fat (p = 0.045) but not to body weight or BMI. No linkage between obesity, diabetes, hypertension, or gallbladder disease and the Trp64Arg mutation was observed in families using affected sib pair linkage analysis or the transmission disequilibrium test. Microsatellite markers proximate to the remaining seven genes were typed in 302 individuals from 59 families. Sib pair linkage analysis provided evidence for linkage between obesity and NPY within affected sibling pairs (p = 0.042; n = 170 pairs). NPY was also linked to weight (p = 0.020), abdominal circumference (p = 0.031), hip circumference (p = 0.012), DBP (p ≤ 0.005), and a composite measure of body mass/fat (p ≤ 0.048) in all sibling pairs (n = 545 pairs). Additionally, LEP was linked to waist/hip ratio (p ≤ 0.009), total cholesterol (p ≤ 0.030), and HDL cholesterol (p ≤ 0.026), and LEPR was linked to fasting blood glucose (p ≤ 0.018) and DBP (p ≤ 0.003). Subsequent to the linkage analyses, the NPY gene was sequenced and eight variant sites identified. Two variant sites (-880I/D and 69I/D) were typed in a random sample of 914 individuals. The 880I/D variant was significantly associated with waist/hip ratio (p = 0.035) in the entire sample (N = 914) and with BMI (p = 0. 031), abdominal circumference (p = 0.044), and waist/hip ratio (p = 0.041) in a non-obese subsample (BW < 30 kg/m2, n = 594). The 69I/D variant was a rare mutation observed in only one pedigree and was not associated with obesity or body size/mass within this pedigree. Results of this study indicate that variation at or near β3AR, LEP, LEPR, and NPY may exert effects which increase obesity susceptibility and influence obesity-related measures in this population. ^
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AIM To compare treatment strategies for respiratory failure in extremely low birth weight (ELBW) infants in Germany in 1997 to Germany, Austria and Switzerland in 2011. METHODS A detailed questionnaire about treatment strategies for ELBW infants was sent to all German centres treating ELBW infants in 1997. A follow-up survey was conducted in 2011 in Germany, Austria and Switzerland. RESULTS In 1997 and 2011, 63.6% and 66.2% of the hospitals responded. In 2011 the response rate was higher in Switzerland than in Germany, and in university hospitals versus non-university hospitals. Treatment strategies did not differ between university and non-university hospitals as well as NICUs of different sizes in 2011. Differences between Germany, Austria and Switzerland were minimal. Administration of caffeine increased significantly, whereas theophylline and doxapram declined (all p<0.001). While the use of dexamethasone decreased and the use of hydrocortisone increased, the overall use of corticosteroids declined (all p<0.001). Between 1997 and 2011 therapy with inhalations and mucolytics decreased (both p<0.001) whereas the use application of diuretics did not change significantly. In mechanically ventilated infants the application of muscle relaxants and sedation declined significantly (p=0.009 and p<0.001), whereas analgesia use did not change. CONCLUSION Treatment strategies for respiratory failure in ELBW infants have changed significantly between 1997 and 2011. This article is protected by copyright. All rights reserved.
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BACKGROUND IL28B genotype predicts response to treatment against hepatitis C virus (HCV) with pegylated interferon/ribavirin (PR) and impacts on the outcome of therapy including telaprevir (TVR). This study aimed to determine the influence of the favorable IL28B genotype on early viral kinetics during therapy with TVR/PR in HIV/HCV-coinfected patients. METHODS All HIV/HCV genotype 1-coinfected subjects who received TVR/PR for at least 4 weeks were included from populations prospectively followed in 22 centers throughout Germany, Switzerland and Spain. RESULTS Of the 129 subjects included, 38 (29.5%) presented with IL28B genotype CC and 94 (72.9%) were treatment-experienced. Ninety-six (73.8%) patients showed undetectable plasma HCV-RNA at treatment week (W) 4: 30 (78.9%) of the IL28B-CC carriers and 65 (71.4%) of the non-CC carriers (p=0.377). Among treatment-naïve patients, proportions of undetectable HCV-RNA among IL28B-CC versus non-CC carriers were 8/9 (88.9%) versus 3/9 (33.3%, p=0.016) and 14/17 (82.4%) versus 11/18 (61.1%, p=0.164) at W2 and W4. The decrease of HCV-RNA at W2 and W4 was similar among the IL28B carriers. CONCLUSIONS IL28B genotype does not predict W4 response to TVR/PR in HIV/HCV-coinfected patients, regardless of their treatment history. However, there is evidence of an impact on response during the first weeks in treatment-naïve patients.
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AIMS To investigate the outcomes of percutaneous coronary intervention (PCI) in bifurcation versus non-bifurcation lesions using the next-generation Resolute zotarolimus-eluting stent (R-ZES). METHODS AND RESULTS We analyzed 3-year pooled data from the RESOLUTE All-Comers trial and the RESOLUTE International registry. The R-ZES was used in 2772 non-bifurcation lesion patients and 703 bifurcation lesion patients, of which 482 were treated with a simple-stent technique (1 stent used to treat the bifurcation lesion) and 221 with a complex bifurcation technique (2 or more stents used). The primary endpoint was 3-year target lesion failure (TLF, defined as the composite of death from cardiac causes, target vessel myocardial infarction, or clinically-indicated target lesion revascularization [TLR]), and was 13.3% in bifurcation vs 11.3% in non-bifurcation lesion patients (adjusted P=.06). Landmark analysis revealed that this difference was driven by differences in the first 30 days between bifurcation vs non-bifurcation lesions (TLF, 6.6% vs 2.7%, respectively; adjusted P<.001), which included significant differences in each component of TLF and in-stent thrombosis. Between 31 days and 3 years, TLF, its components, and stent thrombosis did not differ significantly between bifurcation lesions and non-bifurcation lesions (TLF, 7.7% vs 9.0%, respectively; adjusted P=.50). CONCLUSION The 3-year risk of TLF following PCI with R-ZES in bifurcation lesions was not significantly different from non-bifurcation lesions. However, there was an increased risk associated with bifurcation lesions during the first 30 days; beyond 30 days, bifurcation lesions and non-bifurcation lesions yielded similar 3-year outcomes.
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BACKGROUND Data on pharmacological management during pregnancy are scarce. The aim of this study was to describe the type and frequency of cardiac medication used in pregnancy in patients with cardiovascular disease and to assess the relationship between medication use and fetal outcome. METHODS AND RESULTS Between 2007 and 2011 sixty hospitals in 28 countries enrolled 1321 pregnant women. All patients had structural heart disease (congenital 66%, valvular 25% or cardiomyopathy 7% or ischemic 2%). Medication was used by 424 patients (32%) at some time during pregnancy: 22% used beta-blockers, 8% antiplatelet agents, 7% diuretics, 2.8% ACE inhibitors and 0.5% statins. Compared to those who did not take medication, patients taking medication were older, more likely to be parous, have valvular heart disease and were less often in sinus rhythm. The odds ratio of fetal adverse events in users versus non-users of medication was 2.6 (95% CI 2.0-3.4) and after adjustment for cardiac and obstetric parameter was 2.0 (95% CI 1.4-2.7). Babies of patients treated with beta-blockers had a significantly lower adjusted birth weight (3140 versus 3240 g, p = 0.002). The highest rate of fetal malformation was found in patients taking ACE inhibitors (8%). CONCLUSION One third of pregnant women with heart disease used cardiac medication during their pregnancy, which was associated with an increased rate of adverse fetal events. Birth weight was significantly lower in children of patients taking beta-blockers. A randomized trial is needed to distinguish the effects of the medication from the effects of the underlying maternal cardiac condition.