Software development to standardize the clinical diagnosis of exercise oscillatory ventilation in heart failure.

BACKGROUND: Exercise oscillatory ventilation (EOV) is characterized by periodic oscillations of minute ventilation during cardiopulmonary exercise testing (CPET). Despite its prognostic value in chronic heart failure (HF), its diagnosis is complex due to technical limitations. An easier and more accurate way of EOV identification can contribute to a better approach and clinical diagnosis. This study aims to describe a software development to standardize the EOV diagnosis from CPET's raw data in heart failure patients and test its reliability (intra- and inter-rater). METHODS: The software was developed in the "drag-and-drop" G-language using LabVIEW®. Five EOV definitions (Ben-Dov, Corrà, Kremser, Leite, and Sun definitions), two alternative approaches, one smoothing technique, and some basic statistics were incorporated into the interface to visualize four charts of the ventilatory response. EOV identification was based on a set of criteria verified from the interaction between amplitude, cycle length, and oscillation time. Two raters analyzed the datasets. In addition, repeated measurements were verified after six months using about 25% of the initial data. Cohen's kappa coefficient (κ) was used to investigate the reliability. RESULTS: Overall, 391 tests were analyzed in duplicate (inter-rater reliability) and 100 tests were randomized for new analysis (intra-rater reliability). High inter-rater (κ > 0.80) and intra-rater (κ > 0.80) reliability of the five EOV diagnoses were observed. CONCLUSION: The present study proposes novel semi-automated software to detect EOV in HF, with high inter and intra-rater agreements. The software project and its tutorial are freely available for download.

Application and Measurement Properties of the Talk Test in Cardiopulmonary Patients: A Systematic Review.

Background: The talk test (TT) evaluates the exercise intensity by measuring speech comfort level during aerobic exercise. There are several application protocols available to assess individuals with cardiopulmonary diseases. However, the measurement properties of the TT were not systematically reviewed yet. Methods: A systematic review was developed, registered (CRD420181068930), and reported according to PRISMA Statement. Randomized clinical trials, cross-sectional studies, or series cases were identified through multiple databases and were selected if they presented concomitant speech provocation and an exercise test. Included studies were evaluated based on methodological quality (adapted New Castle-Ottawa Scale), descriptive quality (STROBE Statement), and risk of bias (COSMIN bias risk scale). Results: Ten studies were included. Seven studies presented moderate to high quality and the majority presented good scores according to the STROBE statement. Four hundred and fourteen subjects performed the TT, the majority being patients with coronary artery disease. The test validity was supported by the included studies. Talk Test reliability was considered satisfactory, although only one study presented an adequate reliability analysis. The studies found a correlation between the last positive stage of the TT with the first ventilatory threshold. Workload, oxygen uptake, and heart rate in the last positive stage of the TT were not different from the same parameters related to the first ventilatory threshold. Conclusions: The evidence indicates that the TT is suitable as an alternative tool for the assessment and prescription of exercise in individuals with cardiovascular diseases. The stage when the individual is still able to speak comfortably is suggested as the intensity for aerobic exercise prescription. As there is still no well-defined and fully explored TT protocol, caution is required when interpreting the TT results.

Factors Related to Delayed Diagnosis of Cutaneous Melanoma in the Brazilian Public Health System.

In Brazil, 75% of the population uses the Sistema Único de Saúde (SUS), public health system, where the general practitioner (GP) is responsible for melanoma diagnosis. Identify the factors related to the delay in diagnosing melanoma patients assisted by SUS. A prospective observational study based on a questionnaire and medical records review assessed the sociodemographic features, melanoma signs and symptoms, previous knowledge of the disease, and factors related to delays in seeking medical care. One hundred sixty-six patients were included. Healthcare professionals suspected a lesion in only 23.5% of cases. The average time between lesion suspicion by patient/relative and first medical appointment with GP was over 6 months (31%). The time between the first GP exam and biopsy conducted by a specialist ranged from less than 1 month (34.9%) to more than 1 year (18.7%). Half of the patients (49.4%) experienced delays in histopathological diagnosis due to SUS bureaucracy/slowness. Most (80%) patients did not know what melanoma was before diagnosis. Delay in melanoma diagnosis was related to a lack of knowledge about the disease's signs and symptoms for both the study population and the primary physicians, indicating that both players must receive proper education about melanoma. Also, the infrastructure and work processed at SUS impeded the patient flow, contributing to the diagnosis of the lesions at more advanced stages.

Wells and Geneva Scores Are Not Reliable Predictors of Pulmonary Embolism in Critically Ill Patients: A Retrospective Study.

BACKGROUND: Critically ill patients are at high risk for pulmonary embolism (PE). Specific PE prediction rules have not been validated in this population. The present study assessed the Wells and revised Geneva scoring systems as predictors of PE in critically ill patients. METHODS: Pulmonary computed tomographic angiograms (CTAs) performed for suspected PE in critically ill adult patients were retrospectively identified. Wells and revised Geneva scores were calculated based on information from medical records. The reliability of both scores as predictors of PE was determined using receiver operating characteristic (ROC) curve analysis. RESULTS: Of 138 patients, 42 (30.4%) were positive for PE based on pulmonary CTA. Mean Wells score was 4.3 (3.5) in patients with PE versus 2.7 (1.9) in patients without PE (P < .001). Revised Geneva score was 5.8 (3.3) versus 5.1 (2.5) in patients with versus without PE (P = .194). According to the Wells and revised Geneva scores, 56 (40.6%) patients and 49 (35.5%) patients, respectively, were considered as low probability for PE. Of those considered as low risk by the Wells score, 15 (26.8%) had filling defects on CTA, including 2 patients with main pulmonary artery embolism. The area under the ROC curve was 0.634 for the Wells score and 0.546 for the revised Geneva score. Wells score >4 had a sensitivity of 40%, specificity of 87%, positive predictive value of 59%, and negative predictive value of 77% to predict risk of PE. CONCLUSIONS: In this population of critically ill patients, Wells and revised Geneva scores were not reliable predictors of PE.

Analysis of liver fragment subjected to autologous transplant at rat's retroperitoneum.

BACKGROUND: To investigate the regeneration process of autologous implants of liver on the retroperitoneum. METHODS: Thirty male Fisher rats were used divided in to group 1 (G1): studied 60 d after surgery; group 2 (G2): studied 90 d after surgery; group 3 (G3): studied 180 d after surgery; and group C (GC): animals without surgery. Hepatic fragment was processed for histologic and biochemical analysis. RESULTS: There was inflammatory infiltrate, diffuse hydropic degeneration, necrosis, and moderate fibrosis that reduced in direct relation to the postsurgical time. The concentration of albumin was different between GC and G1 and between G1 and G3 (P = 0.0007). The Catalase (CAT) was related to the time of surgery with GC being different when compared with G1, G2, and G3 (P < 0.0001). The oxidative stress measured through the thiobarbituric acid reactive substances lipid peroxidation was different between the GC and the G2 groups (P = 0.0381). CONCLUSIONS: The analysis made showed hepatic regeneration in the fragment subjected to autologous transplant at the retroperitoneum.

Work absenteeism by parents because of oral conditions in preschool children.

OBJECTIVE: The aim of the present study was to evaluate the influence of oral conditions in preschool children and associated factors on work absenteeism experienced by parents or guardians. METHODS: A preschool-based, cross-sectional study was conducted of 837 children, 3-5 years of age, in Campina Grande, Brazil. Parents or guardians answered the Brazilian version of the Early Childhood Oral Health Impact Scale. The item 'taken time off work' was the dependent variable. Questionnaires addressing sociodemographic variables, history of toothache and health perceptions (general and oral) were also administered. Clinical examinations for dental caries and traumatic dental injury (TDI) were performed by three dentists who had undergone training and calibration exercises. Cohen's kappa (κ) was 0.83-0.88 for interexaminer agreement and 0.85-0.90 for intra-examiner agreement. Descriptive, analytical statistics were conducted, followed by logistic regression for complex samples (α = 5%). RESULTS: The prevalence of parents' or guardians' work absenteeism because of the oral conditions of their children was 9.2%. The following variables were significantly associated with work absenteeism: mother's low schooling [odds ratio (OR) = 2.31; 95% confidence interval (95% CI): 1.31-4.07]; history of toothache (OR = 6.33; 95% CI: 3.18-12.61); and avulsion or luxation types of TDI (OR = 8.54; 95% CI: 1.80-40.53). CONCLUSION: Other oral conditions that do not generally cause pain, such as dental caries with a low degree of severity or inactive dental caries and uncomplicated TDI, were not associated with parents' or guardians' work absenteeism of preschool children. It is concluded that toothache, avulsion, luxation and a low degree of mother's schooling are associated with work absenteeism.

Hemopathogens in naturally infected bovine fetuses in Brazil.

The transplacental transmission of parasites and hemoparasites is crucial for understanding the epidemiology of diseases. This study aimed to assess the prevalence of hemopathogens in bovine fetuses at various gestational periods. Samples were obtained from a slaughterhouse in the state of Minas Gerais, Brazil, and a total of 236 fetuses were collected. DNA extracted from blood samples (145) and organ samples (a pool of brain and spleen) (236) underwent a nested PCR (nPCR) assay to detect Babesia spp., Theileria spp., Trypanosoma vivax, Anaplasma marginale, Anaplasma bovis, Anaplasma phagocytophilum, Ehrlichia minasensis, and hemotropic Mycoplasma spp. Additionally, serological analysis of 145 plasma samples was conducted using the indirect fluorescent antibody test-IFAT to detect IgG against Babesia bovis, Babesia bigemina, A. marginale, and Trypanosoma vivax. The observed prevalence of transplacental transmission was 19.3 %, 6.2 %, 42.7 % and 2.7 %, for A. marginale, B. bigemina, 'Candidatus M. haemobos', and Mycoplasma wenyonii, respectively. The prevalence of A. marginale by gestational trimester was 16 % (13/81) in the second trimester and 23 % (14/60) in the third trimester, with no positive samples in the first trimester. Regarding the species B. bovis and B. bigemina, all evaluated animals tested negative by nPCR, and no serological evidence for B. bovis was found by the IFAT. Babesia bigemina demonstrated an overall seroprevalence of 6.2 % (9/145), with 4.8 % (7/145) in the last trimester and 1.3 % (2/145) in the second trimester of pregnancy. In total, 42.7 % (62/145) of blood samples were positive for 'Candidatus M. haemobos', with 42 % (34/81) in the middle trimester, and 43 % (26/60) in the final trimester of pregnancy. Mycoplasma wenyonni was detected in 2.7 % (4/145) blood samples, all in coinfection with 'C. M. haemobos'. The prevalence by pregnancy trimester was 25 % (1/4) in the first trimester; 1.2 % (1/81) in the second trimester and 3.3 % (2/60) in the third trimester of pregnancy. Hemopathogen DNA was detected in fetus blood samples but not the brain or spleen samples. All the samples were negative for T. vivax, Theileria spp., Anaplasma spp. and Ehrlichia spp. Overall, in this study, approximately 70 % of fetuses were positive for one or more of the studied parasites. No significant associations were observed between pairs of pathogens, except 'C. M. haemobos' and A. marginale.

Diagnostic performance of SARC-F and SARC-CalF in screening for sarcopenia in older adults in Northern Brazil.

To compare the performance of SARC-F and SARC-CalF as screening tools for sarcopenia. Cross-sectional study with a convenience sample of 312 community-dwelling older people. Sarcopenia was defined as low handgrip strength (HGS) or low gait speed (GS ≤ 0.8 m/s). HGS was measured by dynamometry and GS by the 4-m walking speed test. For HGS, six criteria (C) were used to identify sarcopenia in men/women: CI: < 27 kg/16 kg; CII: < 35.5 kg/20.0 kg; CIII: grip over body mass index < 1.05/< 0.79; CIV: grip strength over total body fat < 1.66/< 0.65; CV: grip over bodyweight < 0.45/< 0.34; CVI: < 27 kg/16 kg and low skeletal muscle mass index (SMMI); CI and CVI defined according to the European Working Group on sarcopenia in older people and the rest according to the sarcopenia definition and outcomes Consortium. For sarcopenia screening, the SARC-F (≥ 4 points) and the SARC-CalF (≥ 11 points) were used. The kappa analysis revealed no agreement between the SARC-F and the various criteria for the identification of sarcopenia in men. The same lack of agreement was observed in women with some exceptions: CI = 0.161 ± 0.074, p = 0.020; GS = 0.209 ± 0.076, p = 0.003. Concerning the Cohen's kappa between the SARC-Calf and the reference criteria of sarcopenia, the following coefficients were observed as significant for women: CI = 0.201 ± 0.069, p = 0.003; CII = 0.186 ± 0.064, p = 0.005; GS = 0.273 ± 0.068, p = 0.0001; and for men: CII = 0.139 ± 0.053, p = 0.021; GS = 0.223 ± 0.099, p = 0.011. ROC curves revealed the SARC-Calf with acceptable discrimination and reasonable sarcopenia predictive capacity considering a cutoff value of 10.5 in both men (AUC: 67.5%, p = 0.022; Se = 52.9%; Sp = 76.8%) and women (AUC: 72.4%, p < 0.001; Se = 63%; Sp = 68.5%) concerning GS. The SARC-CalF performed better than the SARC-F for screening sarcopenia in the population ≥ 60 years of age in the Amazonas, measured through walking slowness.

Sleep disturbances and their correlation with cardiovascular risk, obesity, and mood disorders in people with HIV.

BACKGROUND: The relationship between sleep disorders (SDs), cardiovascular risk (CVR), and mood disorders (MDs) has been studied in detail in the general population, but far less in people with HIV (PWH). METHODS: Cross-sectional analysis in single centre cohort of PWH. Sleep quality was assessed using by Epworth Sleepiness Scale (ESS), Insomnia Severity Index (ISI), Berlin Questionnaire (BQ), Pittsburgh Sleep Quality Index (PSQI); anxiety and depression were evaluated by the Generalized Anxiety Disorder-7 and Patient Health Questionnaire-9. Demographic, clinical and HIV-related data were collected, and Framingham and Data collection on Adverse effects of anti-HIV Drugs (DAD)-10 scores were computed in modelling associations with each SDs scale. RESULTS: Data were collected for 721 PWH on stable combination antiretroviral therapy (cART) (median age of 53 years, 71.8% males, 96% with undetectable HIV RNA, 50.3% on cART potentially affecting sleep, and 20.4% on hypno-inducing drugs), 76.9% had SDs 60.3, 31.3, 31.1, and 7.9% at PSQI, BQ, ISI, and ESS, respectively. Anxiety and depression were detected in 28.3 and 16.1% participants, respectively. BQ score was independently associated with high BMI ( P  < 0.001), Framingham risk >10% ( P  < 0.001), and both DAD-10R and -10F score >10% ( P  < 0.001 and P  = 0.031). PSQI and ISI scores were independently associated with depression and anxiety ( P  < 0.001). No association between SDs and specific antiretroviral regimens, nor HIV-related parameters was detected. CONCLUSIONS: In our cohort of PWH on stable ART, despite the alarmingly higher prevalence, SDs were associated with the same determinants (cardiovascular risk factors and MDs) observed in the general population.

Muscle Weakness and Walking Slowness for the Identification of Sarcopenia in the Older Adults from Northern Brazil: A Cross-Sectional Study.

Background: This study aimed to analyze the prevalence of sarcopenia in elderly people from Northern Brazil according to muscle weakness or walking slowness. Methods: The sample consisted of 312 elderly people (72.6 ± 7.8 years). For walking slowness, a gait speed ≤ 0.8 m/s was used as a cut-off value, and for muscle weakness the following handgrip strength criteria were used for men and women, respectively: CI: <27.0/16.0 kg; CII: <35.5/20.0 kg; CIII: grip strength corrected for body mass index (BMI) < 1.05/0.79; CIV: grip strength corrected for total fat mass: <1.66/0.65; CV: grip strength corrected for body mass: <0.45/0.34. Results: Walking speed was reduced in 27.0% of women and 15.2% of men (p < 0.05). According to grip strength criteria, 28.5% of women and 30.4% of men (CI), 58.0% of women and 75.0% of men (CII), 66.0% of women and 39.3% of men (CIII), 28.8% of women and 19.6% of men (CIV), and 56.5% of women and 50.0% of men (CV) were identified as having sarcopenia. Conclusions: Walking slowness is more prevalent in women and muscle weakness is more prevalent in men in Northern Brazil. Walking slowness proved to be more concordant with muscle weakness in both sexes when the CI for handgrip strength was adopted.

Sensitivity and specificity of different exercise oscillatory ventilation definitions to predict 2-year major adverse cardiovascular outcomes in chronic heart failure patients.

BACKGROUND: Exercise oscillatory ventilation (EOV) shows a four-fold greater risk of adverse events. This study aims to analyze the sensitivity and specificity of three EOV diagnostic definitions to predict adverse outcomes at a 2-year follow-up and to compare its EOV prevalence and relations with the patient's profile. METHODS: Cardiopulmonary exercise tests from 233 heart failure patients were analyzed. Two blinded reviewers used a semiautomated software to identify EOV cases pattern according to the definitions of Ben-Dov, Corrà, and Leite. Data were grouped in EOV-positive or EOV-negative according to each definition. Baseline characteristics, EOV prevalence, relative risk, sensitivity, and specificity to predict 2-years of major adverse cardiovascular outcomes were analyzed. RESULTS: The Corrà definition led to the best prediction of 2-year major cardiovascular adverse outcomes (HR 2.46 [1.16 to 5.25]; p = 0.019, AUC = 0.618; p = 0.007). EOV prevalence was 17.2%, 17.2%, and 9.4% applying Ben-Dov, Corrà, and Leite definition, respectively. The main clinical differences between EOV-positive and EOV-negative patients were: MECKI score and VE/VCO2 slope (all definitions), and BNP levels (Ben-Dov and Leite). BNP levels were correlated with amplitude (rho = 0.255; p = 0.033) and cycle length (rho = 0.388; p = 0.002). CONCLUSION: Corrà definition was the only one that exhibited the capacity to predict major adverse cardiovascular outcomes at a 2-year follow-up. Regardless of its definition, EOV was more often prevalent in patients with a greater MECKI score and VE/VCO2 slope values.

Evaluation of the Reliability and Reproducibility of the Roussouly Classification for Lumbar Lordosis Types.

Objective The present study aims to determine the intra- and inter-rater reliability and reproducibility of the Roussouly classification for lumbar lordosis types. Methods A database of 104 panoramic, lateral radiographs of the spine of male individuals aged between 18 and 40 years old was used. Six examiners with different expertise levels measured spinopelvic angles and classified lordosis types according to the Roussouly classification using the Surgimap software (Nemaris Inc., New York, NY, USA). After a 1-month interval, the measurements were repeated, and the intra- and inter-rater agreement were calculated using the Fleiss Kappa test. Results The study revealed positive evidence regarding the reproducibility of the Roussouly classification, with reasonable to virtually perfect (0.307-0.827) intra-rater agreement, and moderate (0.43) to reasonable (0.369) inter-rater agreement according to the Fleiss kappa test. The most experienced examiners showed greater inter-rater agreement, ranging from substantial (0.619) to moderate (0.439). Conclusion The Roussouly classification demonstrated good reliability and reproducibility, with intra- and inter-rater agreements at least reasonable, and reaching substantial to virtually perfect levels in some situations. Evaluators with highest expertise levels showed greater intra and inter-rater agreement.

Effects of Magnetite Nanoparticles and Static Magnetic Field on Neural Differentiation of Pluripotent Stem Cells.

Neurodevelopmental processes of pluripotent cells, such as proliferation and differentiation, are influenced by external natural forces. Despite the presence of biogenic magnetite nanoparticles in the central nervous system and constant exposure to the Earth's magnetic fields and other sources, there is scant knowledge regarding the role of electromagnetic stimuli in neurogenesis. Moreover, emerging applications of electrical and magnetic stimulation to treat neurological disorders emphasize the relevance of understanding the impact and mechanisms behind these stimuli. Here, the effects of magnetic nanoparticles (MNPs) in polymeric coatings and the static external magnetic field (EMF) were investigated on neural induction of murine embryonic stem cells (mESCs) and human induced pluripotent stem cells (hiPSCs). The results show that the presence of 0.5% MNPs in collagen-based coatings facilitates the migration and neuronal maturation of mESCs and hiPSCs in vitro. Furthermore, the application of 0.4 Tesla EMF perpendicularly to the cell culture plane, discernibly stimulates proliferation and guide fate decisions of the pluripotent stem cells, depending on the origin of stem cells and their developmental stage. Mechanistic analysis reveals that modulation of ionic homeostasis and the expression of proteins involved in cytostructural, liposomal and cell cycle checkpoint functions provide a principal underpinning for the impact of electromagnetic stimuli on neural lineage specification and proliferation. These findings not only explore the potential of the magnetic stimuli as neural differentiation and function modulator but also highlight the risks that immoderate magnetic stimulation may affect more susceptible neurons, such as dopaminergic neurons.

MEF2C repressor variant deregulation leads to cell cycle re-entry and development of heart failure.

BACKGROUND: A pathophysiological link exists between dysregulation of MEF2C transcription factors and heart failure (HF), but the underlying mechanisms remain elusive. Alternative splicing of MEF2C exons α, ß and γ provides transcript diversity with gene activation or repression functionalities. METHODS: Neonatal and adult rat ventricular myocytes were used to overexpress MEF2C splicing variants γ+ (repressor) or γ-, or the inactive MEF2Cγ+23/24 (K23T/R24L). Phenotypic alterations in cardiomyocytes were determined by confocal and electron microscopy, flow cytometry and DNA microarray. We used transgenic mice with cardiac-specific overexpression of MEF2Cγ+ or MEF2Cγ- to explore the impact of MEF2C variants in cardiac phenotype. Samples of non-infarcted areas of the left ventricle from patients and mouse model of myocardial infarction were used to detect the expression of MEF2Cγ+ in failing hearts. FINDINGS: We demonstrate a previously unrealized upregulation of the transrepressor MEF2Cγ+ isoform in human and mouse failing hearts. We show that adenovirus-mediated overexpression of MEF2Cγ+ downregulates multiple MEF2-target genes, and drives incomplete cell-cycle reentry, partial dedifferentiation and apoptosis in the neonatal and adult rat. None of these changes was observed in cardiomyocytes overexpressing MEF2Cγ-. Transgenic mice overexpressing MEF2Cγ+, but not the MEF2Cγ-, developed dilated cardiomyopathy, correlated to cell-cycle reentry and apoptosis of cardiomyocytes. INTERPRETATION: Our results provide a mechanistic link between MEF2Cγ+ and deleterious abnormalities in cardiomyocytes, supporting the notion that splicing dysregulation in MEF2C towards the selection of the MEF2Cγ+ variant contributes to the pathogenesis of HF by promoting cardiomyocyte dropout. FUNDING: São Paulo Research Foundation (FAPESP); Brazilian National Research Council (CNPq).

Regarding: "Inspiratory muscle training improves performance of a repeated sprints ability test in professional soccer players".

The Journal of Bodywork & Movement Therapies recently published an article by Silva et al., entitled "Inspiratory muscle training improves performance of a repeated sprints ability test in professional soccer players" (Silva et al., 2019). After close reading we find that the new findings of Silva et al., (2019) are relevant and provide a promising indication that IMT can improve the performance of young male soccer players. However, some additional important points must be considered when interpreting these positive findings.

The effects of inspiratory muscle training with linear workload devices on the sports performance and cardiopulmonary function of athletes: A systematic review and meta-analysis.

Inspiratory muscle training (IMT) is considered an ergogenic resource to improve sports performance. The aim of this systematic review is to evaluate the effects of IMT with linear workload devices (IMT-linear) on the sports performance and cardiopulmonary function of athletes. A search was conducted on several databases until July 2018. Eligible studies were independently reviewed by two reviewers. Methodological quality and quality of evidence were assessed with PEDro' score and GRADE, respectively. Statistical analysis was performed using the Review Manager 5.3 software. Twenty-five studies were selected for analysis. A total of 207 athletes were allocated to the IMT group, 143 athletes to the IMT-Sham, and 86 healthy individuals to the control group. The quality of studies was high (6 [3-8] points). IMT-linear improved maximal inspiratory pressure (MD -29.42 cmH2O [-35.65, -23.20]; p < 0.001), independent of sports modality. There was no influence of IMT on the maximal expiratory pressure and pulmonary function markers. It was observed that IMT-linear improves the sports performance (SMD 0.64 [0.35, 0.92]; p < 0.0001) with moderate effect size. The results suggest that IMT-linear represents an effective tool to improve the inspiratory muscle strength of athletes, as well as sports performance. However, IMT-linear did not shown effect on cardiopulmonary function.

Can RR intervals editing and selection techniques interfere with the analysis of heart rate variability?

BACKGROUND: Oscillation between successive sinus beats or RR intervals, termed heart rate variability, is an important marker of autonomic function of the heart. However, its analysis may be influenced by the database recorded based on the occurrence of interference. OBJECTIVE: To evaluate if the techniques of identification and editing of artifacts, as well as the selection methods of RR intervals, can interfere with heart rate variability analysis. METHODS: The RR intervals of 56 subjects (30 aortic stenosis patients, 14 physically active individuals, 12 amateur athletes) were recorded for 10min using a heart rate monitor. Values with differences greater than 20%, higher than three standard deviations or outside of the normal curve (95% confidence interval) were considered artifacts. These points were corrected through data replacement, adjacent, linear and polynomial interpolation, or excluded. Then, the 256 highest stability points and the last 5min of recordings were chosen. The software programs, Kubios HRV and GraphPAD, were used to calculate and to analyze the indices of heart rate variability, respectively. RESULTS: Strong agreement was observed among the identification algorithms; there was no difference between the correction techniques (p=0.95); and the selection methods exhibited different sections (p<0.01) with a direct influence on approximated entropy (p<0.05). CONCLUSION: With short-term recordings, selection methods may interfere with the non-linear heart rate variability analysis. The confidence interval, the replacement by the average of previous data and the selection of 256 of the highest stability points of the signal seem to be the most adequate procedures to treat the data with prior to analysis.