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1.
BMC Nephrol ; 24(1): 213, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464291

RESUMO

BACKGROUND: Chronic Kidney Disease (CKD) is a prevalent and life-threatening situation recognized as an emerging health issue. The present study aimed to evaluate the effect of demographic and laboratory parameters on the survival of patients with End-Stage Renal Disease (ESRD) in a hemodialysis (HD) center in Iran. MATERIALS AND METHODS: This study was conducted on patients receiving chronic HD in Iran Helal Pharmaceutical and Clinical Complex between 2014 and 2018. The survival time was considered as the time interval between HD initiation and death. Receiving kidney transplantation was regarded as a competing risk, and an improper form of two-parameter Weibull distribution was utilized to simultaneously model the time to both death and renal transplantation. The Bayesian approach was conducted for parameters estimation. RESULTS: Overall, 29 (26.6%) patients expired, and 19 (17.4%) received kidney transplants. The male gender was related to poor survival, having nearly 4.6 folds higher hazard of mortality (90% HPD region: 1.36-15.49). Moreover, Serum calcium levels [Formula: see text]9.5 mg/dL (adjusted Sub-hazard ratio (S-HR)=2.33, 90% HPD region: 1.05-5.32) and intact parathyroid hormone (iPTH) [Formula: see text]150 pg/mL (adjusted S-HR = 2.56, 90% HPD region: 1.09-6.15) were associated with an elevated hazard of mortality. The cumulative incidence function (CIF) for transplantation was greater than death in the first two years of the study. Subsequently, the CIF for death exceeded transplantation in the following two years. The 4-year cumulative incidence of death and kidney transplantation was 63.7% and 36.3%, respectively. CONCLUSION: Male gender, hypercalcemia, and hypoparathyroidism were associated with worse outcomes. Correcting mentioned laboratory parameters may improve patients' survival in the HD population.


Assuntos
Falência Renal Crônica , Transplante de Rim , Insuficiência Renal Crônica , Humanos , Masculino , Teorema de Bayes , Falência Renal Crônica/epidemiologia , Diálise Renal
2.
Heart Lung Circ ; 31(5): 647-657, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35063378

RESUMO

BACKGROUND: Renal disease confers a strong independent risk for morbidity and mortality after percutaneous coronary intervention (PCI). We evaluated the relationship between baseline pre-procedural renal function and outcomes following PCI. METHODS: We examined 45,287 patients who underwent PCI in British Columbia. We evaluated all-cause mortality and target vessel revascularisation (TVR) at 2 years. Pre-procedural renal impairment was categorised by creatinine clearance (CrCl, mL/min): CrCl≥90 (n=14,876), 90>CrCl≥60 (n=10,219), 60>CrCl≥30 (n=14,876), 30>CrCl≥0 (n=2,594) and dialysis (n=579). RESULTS: Declining CrCl values less than 60 mL/min were progressively associated with greater mortality: 60>eGFR≥30 (HR=2.01, 95% CI 1.71-2.37, p<0.001); 30>eGFR≥0 (HR=4.10, 95% CI 3.39-4.95, p<0.001); and dialysis (HR=6.22, 95% CI 5.07-7.63, p<0.001). A reduction in eGFR was not associated with TVR in non-dialysis patients. However, dialysis was a strong independent predictor for TVR (HR=1.69, 95% CI 1.37-2.08, p<0.001). This was confirmed in propensity-matched analyses where, dialysis was strongly associated with TVR (HR=1.53, 95% CI 1.24-1.89, p<0.001). This association was consistently seen in stratified analyses for diabetic versus non-diabetic patients; stent length >30 mm versus <30 mm; stent diameter >3 mm versus <3 mm; and receipt of bare metal stents versus drug-eluting stents. CONCLUSIONS: This study indicates the association with declining renal function and mortality in patients undergoing PCI. Whilst renal disease was not associated with increased TVR in non-dialysis patients, dialysis-dependence was a strong independent predictor for increased TVR.


Assuntos
Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Insuficiência Renal , Colúmbia Britânica , Doença da Artéria Coronariana/complicações , Feminino , Humanos , Masculino , Intervenção Coronária Percutânea/efeitos adversos , Sistema de Registros , Insuficiência Renal/etiologia , Fatores de Risco , Stents , Resultado do Tratamento
3.
Langmuir ; 37(51): 14785-14792, 2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-34813341

RESUMO

Our experiments on the rod-climbing effect with an oil-coated rod revealed two key differences in the rod-climbing phenomena compared to a bare rod. First, an enhancement in the magnitude of climbing height for any particular value of the rod rotational speed and second, a decrease in the threshold rod rotational speed required for the appearance of the rod-climbing effect were observed. Observed phenomena are explained by considering the contact line behavior at the rod-fluid interface. Transient evolution of the meniscus at the rod-fluid interface revealed that the three-phase contact line was pinned for a bare rod and depinned for an oil-coated rod. We modeled the subject fluid as a Giesekus fluid to predict the climbing height. The differences in the contact line behavior were incorporated via the contact angle at the rod-fluid interface as a boundary condition. Agreement was found between the observed and predicted climbing height, establishing that contact line behavior may modulate the rod-climbing effect.

4.
Europace ; 23(8): 1295-1301, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-33570096

RESUMO

AIMS: There is limited information on the role of screening with electrocardiography (ECG) for identifying cardiovascular diseases associated with sudden cardiac death (SCD) in a non-select group of adolescents and young adults in the general population. METHODS AND RESULTS: Between 2012 and 2014, 26 900 young individuals (aged 14-35 years) were prospectively evaluated with a health questionnaire and ECG. Individuals with abnormal results underwent secondary investigations, the costs of which were being based on the UK National Health Service tariffs. Six hundred and seventy-five (2.5%) individuals required further investigation for an abnormal health questionnaire, 2175 (8.1%) for an abnormal ECG, and 114 (0.5%) for both. Diseases associated with young SCD were identified in 88 (0.3%) individuals of which 15 (17%) were detected with the health questionnaire, 72 (81%) with ECG and 2 (2%) with both. Forty-nine (56%) of these individuals received medical intervention beyond lifestyle modification advice in the follow-up period of 24 months. The overall cost of the evaluation process was €97 per person screened, €17 834 per cardiovascular disease detected, and €29 588 per cardiovascular disease associated with SCD detected. Inclusion of ECG was associated with a 36% cost reduction per diagnosis of diseases associated with SCD compared with the health questionnaire alone. CONCLUSION: The inclusion of an ECG to a health questionnaire is associated with a five-fold increase in the ability to detect disease associated with SCD in young individuals and is more cost effective for detecting serious disease compared with screening with a health questionnaire alone.


Assuntos
Cardiopatias , Medicina Estatal , Adolescente , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/prevenção & controle , Eletrocardiografia , Cardiopatias/diagnóstico , Humanos , Programas de Rastreamento , Adulto Jovem
6.
J Am Heart Assoc ; 12(11): e028038, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37232270

RESUMO

Background No data currently exist comparing the contemporary iterations of balloon-expandable (BE) Edwards SAPIEN 3/Ultra and the self-expanding (SE) Medtronic Evolut PRO/R34 valves. The aim of the study was the comparison of these transcatheter heart valves with emphasis on patients with small aortic annulus. Methods and Results In this retrospective registry, periprocedural outcomes and midterm all-cause mortality were analyzed. A total of 1673 patients (917 SE versus 756 BE) were followed up for a median of 15 months. A total of 194 patients died (11.6%) during follow-up. SE and BE groups showed similar survival at 1 (92.6% versus 90.6%) and 3 (80.3% versus 85.2%) years (Plog-rank=0.136). Compared with the BE group, patients treated with the SE device had lower peak (16.3±8 mm Hg SE versus 21.9±8 mm Hg BE) and mean (8.8±5 mm Hg SE versus 11.5±5 mm Hg BE) gradients at discharge. Conversely, the BE group demonstrated lower rates of at least moderate paravalvular regurgitation postoperatively (5.6% versus 0.7% for SE and BE valves, respectively; P<0.001). In patients treated with small transcatheter heart valves (≤26 mm for SE and ≤23 mm for BE; N=284 for SE and N=260 for BE), survival was higher among patients treated with SE valves at both 1 (96.7% SE versus 92.1% BE) and 3 (91.8% SE versus 82.2% BE) years (Plog-rank=0.042). In propensity-matched patients treated with small transcatheter heart valve, there remained a trend for higher survival among the SE group at both 1 (97% SE versus 92.3% BE) and 3 years (91.8% SE versus 78.7% BE), Plog-rank=0.096). Conclusions Real-world comparison of the latest-generation SE and BE devices demonstrated similar survival up to 3 years' follow-up. In patients with small transcatheter heart valves, there may be a trend for improved survival among those treated with SE valves.


Assuntos
Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Desenho de Prótese
7.
Eur Heart J ; 32(18): 2304-13, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21613263

RESUMO

AIMS: Athletic training in male black athletes (BAs) is associated with marked ECG repolarization changes that overlap with hypertrophic cardiomyopathy (HCM). Differentiating between the two entities is prudent since BAs exhibit a higher prevalence of exercise-related sudden death from HCM compared with white athletes (WAs). METHODS AND RESULTS: Between 1996 and 2010, 904 BAs underwent serial cardiac evaluations including ECG and echocardiography. Athletes exhibiting T-wave inversions were investigated further for HCM. Results were compared with 1819 WAs, 119 black controls (BCs), and 52 black HCM patients. Athletes were followed up for 69.7 ± 29.6 months. T-wave inversions were present in 82.7% HCM patients, 22.8% BAs, 10.1% BCs, and 3.7% WAs. In athletes, the major determinant of T-wave inversions was black ethnicity. T-wave inversions in BAs (12.7%) were predominantly confined to contiguous anterior leads (V1-V4). Only 4.1% of BAs exhibited T-wave inversions in the lateral leads. In contrast, both BCs and HCM patients exhibited lower prevalence of T-wave inversions in leads V1-V4 (4.2 and 3.8%, respectively) with most T-wave inversions in HCM patients (76.9%) involving the lateral leads. During follow-up one BA survived cardiac arrest and two athletes (one BA, one WA) were diagnosed with HCM. All three exhibited T-wave inversions in the lateral leads. CONCLUSIONS: T-wave inversions in leads V1-V4 appear to represent an ethnic variant of 'athlete's heart'. Conversely, T-wave inversions in the lateral leads may represent the initial expression of underlying cardiomyopathy and merit further evaluation and regular surveillance.


Assuntos
Arritmias Cardíacas/diagnóstico , População Negra , Cardiomegalia Induzida por Exercícios/fisiologia , Cardiomiopatia Hipertrófica/diagnóstico , Esportes/fisiologia , Adolescente , Adulto , Arritmias Cardíacas/etnologia , Cardiomiopatia Hipertrófica/etnologia , Diagnóstico Diferencial , Ecocardiografia , Eletrocardiografia , Eletrocardiografia Ambulatorial , Teste de Esforço , França/epidemiologia , Sistema de Condução Cardíaco/fisiologia , Humanos , Masculino , Prevalência , Reino Unido/epidemiologia , Adulto Jovem
8.
Biophys J ; 101(5): 1123-9, 2011 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-21889449

RESUMO

Many prokaryotic transcription factors home in on one or a few target sites in the presence of a huge number of nonspecific sites. Our analysis of λ-repressor in the Escherichia coli genome based on single basepair substitution experiments shows the presence of hundreds of sites having binding energy within 3 Kcal/mole of the O(R)1 binding energy, and thousands of sites with binding energy above the nonspecific binding energy. The effect of such sites on DNA-based processes has not been fully explored. The presence of such sites dramatically lowers the occupation probability of the specific site far more than if the genome were composed of nonspecific sites only. Our Brownian dynamics studies show that the presence of quasi-specific sites results in very significant kinetic effects as well. In contrast to λ-repressor, the E. coli genome has orders of magnitude lower quasi-specific sites for GalR, an integral transcription factor, thus causing little competition for the specific site. We propose that GalR and perhaps repressors of the same family have evolved binding modes that lead to much smaller numbers of quasi-specific sites to remove the untoward effects of genomic DNA.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Genoma Bacteriano/genética , Modelos Biológicos , Sítios de Ligação , Proteínas de Escherichia coli/metabolismo , Cinética , Proteínas Repressoras/metabolismo , Termodinâmica , Proteínas Virais Reguladoras e Acessórias/metabolismo
9.
J Cardiovasc Magn Reson ; 13: 77, 2011 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-22122802

RESUMO

Regular and prolonged exercise is associated with increased left ventricular wall thickness that can overlap with hypertrophic cardiomyopathy (HCM). Differentiating physiological from pathological hypertrophy has important implications, since HCM is the commonest cause of exercise-related sudden cardiac death in young individuals. Most deaths have been reported in intermittent 'start-stop' sports such as football (soccer) and basketball. The theory is that individuals with HCM are unable to augment stroke volume sufficiently to meet the demands of endurance sports and are accordingly 'selected-out' of participation in such events. We report the case of an ultra-endurance athlete with 25 years of > 50 km competitive running experience, with genetically confirmed HCM; thereby demonstrating that these can be two compatible entities.


Assuntos
Cardiomiopatia Hipertrófica Familiar/fisiopatologia , Resistência Física , Corrida , Adulto , Doenças Assintomáticas , Cardiomiopatia Hipertrófica Familiar/diagnóstico , Cardiomiopatia Hipertrófica Familiar/genética , Proteínas de Transporte/genética , Análise Mutacional de DNA , Ecocardiografia Doppler em Cores , Eletrocardiografia , Teste de Esforço , Predisposição Genética para Doença , Humanos , Imageamento por Ressonância Magnética , Masculino , Mutação , Fenótipo
10.
Phys Sportsmed ; 38(1): 54-63, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20424402

RESUMO

The beneficial effects of regular physical exercise on cardiovascular morbidity and mortality are well documented. In rare cases, however, athletes with cardiovascular abnormalities are at increased risk of exercise-related sudden cardiac death (SCD). Paradoxically, most SCDs can be attributed to cardiovascular abnormalities that can be identified during an athlete's life. Such abnormalities can be minimized by several therapeutic strategies, including insertion of an implantable cardioverter-defibrillator. Based on these considerations, the medical and sporting governing bodies recommend preparticipation cardiovascular screening (PPS) in young competitive athletes (aged

Assuntos
Atletas , Morte Súbita Cardíaca/prevenção & controle , Testes Diagnósticos de Rotina , Adolescente , Cardiomiopatias/diagnóstico , Criança , Eletrocardiografia , Feminino , Humanos , Masculino , Adulto Jovem
11.
Europace ; 11(12): 1696-701, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19880853

RESUMO

AIMS: During head-up tilt (HUT) testing, a period of haemodynamic instability, marked by oscillations in blood pressure, often precedes vasovagal syncope. We hypothesized that the presence of oscillations in blood pressure during HUT testing predicts a positive diagnosis for vasovagal syncope. METHODS AND RESULTS: The haemodynamic profiles of 42 consecutive patients non-responsive to passive HUT and glyceryl trinitrate (GTN) provocation ('non-responders') and, contemporaneously, 41 consecutive patients responsive to passive HUT and GTN provocation ('responders') were assigned oscillation-positive or oscillation-negative depending on the presence or absence of a characteristic oscillation in systolic blood pressure which varied by > or =30 mmHg (peak-to-trough). All the non-responders proceeded to an isoprenaline (Iso) challenge test. Of the 42 non-responders, 27 patients were Iso tilt-positive; all of these patients were assigned oscillation-positive. The other 15 non-responders were Iso tilt-negative; of these 9 were assigned oscillation-positive and 6 were assigned oscillation-negative. Of the 41 responder patients, 33 were assigned oscillation-positive, whereas 8 were assigned oscillation-negative. Overall, the presence of oscillations as a diagnostic predictor for vasovagal syncope had a sensitivity of 88% (positive predictive value of 87%) and a specificity of 40% (negative predictive value of 43%). CONCLUSION: In patients non-responsive to passive HUT and GTN provocation, the presence of an oscillating systolic blood pressure varying > or =30 mmHg may still indicate a diagnosis of vasovagal syncope, possibly obviating the need for Iso testing.


Assuntos
Determinação da Pressão Arterial/métodos , Diagnóstico por Computador/métodos , Oscilometria/métodos , Síncope Vasovagal/diagnóstico , Teste da Mesa Inclinada/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Artigo em Inglês | MEDLINE | ID: mdl-30502581

RESUMO

Hepatitis C virus (HCV) requires an essential host factor, human La protein, for its translation and replication activity. Earlier, it was demonstrated that a 24-mer synthetic peptide (LaR2C) encompassing residues 112 to 184 of the natural human La protein interacts with the HCV internal ribosome entry site (IRES) and inhibits translation. Interestingly, a shorter version of the same LaR2C peptide, LaR2C-N7, containing residues 174 to 180 (KYKETDL), with a unique ß-turn secondary structure, is sufficient to inhibit IRES mediated translation of HCV. Hence, it is imperative to understand the role of each amino acid of this heptapeptide towards ß-turn formation which will then help in designing potential drugs against HCV infection. Here, we use Nanoscale Molecular Dynamics (NAMD) simulation to investigate the factors modulating its ß-turn formation and stability. Using 100 ns simulation paradigms, we find that the peptide populated the type 1 ß-turn conformation in its free form in solution. However, simulation of the single-site mutants of the heptapeptide revealed that none of the 7 mutants retained the ß-turn conformation with sufficient stability. We observed that the ß-turn was stabilized mainly by the side chain interaction, salt-bridge and weak hydrogen bonds between K3 and D6 residues. Y2, K1 and K3 sites upon mutation heavily destabilized the ß-turn when compared to alteration at the E4 and T5 sites which would then drastically reduce its HCV RNA IRES binding capabilities. Taken together, our results provide a basis for designing peptidomimetics as potential anti-HCV drug candidates.


Assuntos
Fragmentos de Peptídeos/química , Fosfoproteínas/química , Biossíntese de Proteínas/efeitos dos fármacos , Antivirais/química , Antivirais/farmacologia , Hepacivirus/patogenicidade , Hepatite C/tratamento farmacológico , Humanos , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/farmacologia , Estabilidade Proteica
13.
J Child Psychol Psychiatry ; 49(7): 723-32, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18492037

RESUMO

BACKGROUND: To investigate the level of posttraumatic stress and depressive symptoms, and background risk and protective factors that might increase or ameliorate this distress amongst unaccompanied asylum-seeking children and adolescents (UASC). METHODS: Cross-sectional survey carried out in London. Participants were 78 UASC aged 13-18 years, predominantly from the Balkans and Africa, compared with 35 accompanied refugee children. Measures included self-report questionnaires of war trauma, posttraumatic stress and depressive symptoms. RESULTS: UASC had experienced high levels of losses and war trauma, and posttraumatic stress symptoms. Predictors of high posttraumatic symptoms included low-support living arrangements, female gender and trauma events, and increasing age only amongst the UASC. High depressive scores were associated with female gender, and region of origin amongst the UASC. CONCLUSION: UASC might have less psychological distress if offered high-support living arrangements and general support as they approach the age of 18 years, but prospective studies are required to investigate the range of risk and protective factors.


Assuntos
Adaptação Psicológica , Transtornos de Adaptação/psicologia , Jovens em Situação de Rua/psicologia , Refugiados/psicologia , Apoio Social , Transtornos de Estresse Pós-Traumáticos/psicologia , Transtornos de Adaptação/diagnóstico , Adolescente , Estudos Transversais , Feminino , Humanos , Acontecimentos que Mudam a Vida , Londres , Masculino , Inventário de Personalidade , Fatores de Risco , Fatores Sexuais , Serviço Social , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Inquéritos e Questionários
14.
Waste Manag ; 28(10): 1993-2002, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17950591

RESUMO

We present here a study of the sintering of fly ash and its mixture with low alkali pyrophyllite in the presence of sodium hexa meta phosphate (SHMP), a complex activator of sintering, for the purpose of wall tile manufacturing. The sintering of fly ash with SHMP in the temperature range 925-1050 degrees C produces tiles with low impact strength; however, the incremental addition of low alkali pyrophyllite improves impact strength. The impact strength of composites with >or=40% (w/w) pyrophyllite in the fly ash-pyrophyllite mix satisfies the acceptable limit (19.6 J/m) set by the Indian Standards Institute for wall tiles. Increasing the pyrophyllite content results in an increase in the apparent density of tiles, while shrinkage and water absorption decrease. The strength of fly ash tiles is attributed to the formation of a silicophosphate phase; in pyrophyllite rich tiles, it is attributed to the formation of a tridymite-structured T-AlPO(4) phase. Scanning electron micrographs show that the reinforcing rod shaped T-AlPO(4) crystals become more prominent as the pyrophyllite content increases in the sintered tiles.


Assuntos
Silicatos de Alumínio/química , Carbono/química , Materiais de Construção , Material Particulado/química , Fosfatos/química , Adsorção , Cerâmica/química , Cinza de Carvão , Temperatura Baixa , Mecânica , Microscopia Eletrônica de Varredura , Água/química , Difração de Raios X
15.
JACC Clin Electrophysiol ; 2(5): 587-595, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29759578

RESUMO

OBJECTIVES: The purpose of this study was to determine the potential value of a novel marker for the severity of structural heart disease and the risk of arrhythmia. BACKGROUND: The ventricular ectopic QRS interval (VEQSI) has been shown to identify structural heart disease and predict mortality in an unselected population. In ischemic heart disease (IHD), risk stratification for sudden death is imperfect. We hypothesized that VEQSI would identify patients with prior myocardial infarction (MI) compared with healthy subjects and distinguish IHD patients who have suffered life-threatening events from those without prior significant ventricular arrhythmia. METHODS: The 12-lead Holter recordings from 189 patients with previous MI were analyzed: 38 with prior ventricular tachycardia/ventricular fibrillation (MI-VT/VF) (66 ± 9 years; 92% male); 151 without prior significant ventricular arrhythmia (MI-no VT/VF) (64 ± 11 years; 74% male). These were compared with 60 healthy controls (62 ± 7 years; 70% male). All ventricular ectopic beats were reviewed and maximal VEQSI duration (VESQI max) was recorded as the duration of the longest ventricular ectopic beat. RESULTS: VEQSI max was longer in post-MI patients compared with normal controls (185 ± 26 ms vs. 164 ± 16 ms; p < 0.001) and in MI-VT/VF patients with prior life-threatening events compared with MI-no VT/VF patients without prior life-threatening events (214 ± 20 ms vs. 177 ± 22 ms; p < 0.001). Multivariate analysis established VEQSI max as the strongest independent marker for prior serious ventricular arrhythmia. VEQSI max >198 ms had 86% sensitivity, 85% specificity, 62% positive predictive value, and 96% negative predictive value for identifying patients with prior life-threatening events (odds ratio: 37.4; 95% confidence interval: 13.0 to 107.5). CONCLUSIONS: VEQSI max >198 ms distinguishes post-MI patients with prior life-threatening events from those without prior significant ventricular arrhythmia. This may be a useful additional index for risk stratification in IHD.

16.
J Am Coll Cardiol ; 63(19): 2028-34, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24583300

RESUMO

OBJECTIVES: This study sought to investigate the prevalence of potentially abnormal electrocardiographic (ECG) patterns in young individuals to assess the implications for a nationwide screening program for conditions causing sudden cardiac death (SCD). BACKGROUND: The Italian experience suggests that pre-participation screening with ECG reduces the incidence of SCD in athletes. However, the majority of SCDs occur in nonathletes. In the United Kingdom, screening for cardiac disorders is confined to symptomatic individuals or those with a family history of inherited cardiac conditions or premature cardiac death. METHODS: Between 2008 and 2012, 7,764 nonathletes ages 14 to 35 years underwent ECG screening. Electrocardiograms were analyzed for group 1 (training-related) and group 2 (potentially pathological) patterns presented in the 2010 European Society of Cardiology position paper, which advocates further evaluation for individuals with group 2 ECG patterns. Results were compared with 4,081 athletes. RESULTS: Group 1 patterns occurred in 49.1% of nonathletes and 87.4% of athletes (p < 0.001). Group 2 patterns occurred in 21.8% of nonathletes and 33% of athletes (p < 0.001). In nonathletes, QTc interval abnormalities comprised the majority (52%) of group 2 changes, whereas T-wave inversions constituted 11%. Male sex and African/Afro-Caribbean ethnicity demonstrated the strongest association with group 2 ECG patterns. CONCLUSIONS: The study demonstrates that 1 in 5 young people have group 2 ECG patterns. The low incidence of SCD in young people suggests that in most instances such patterns are non-specific. These findings have significant implications on the feasibility and cost-effectiveness of nationwide screening programs for cardiovascular disease in young nonathletes and athletes alike, on the basis of current guidelines.


Assuntos
Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Eletrocardiografia , Programas de Rastreamento , Adolescente , Adulto , Doenças Cardiovasculares/fisiopatologia , Estudos Transversais , Morte Súbita Cardíaca/epidemiologia , Eletrocardiografia/métodos , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Prevalência , Reino Unido/epidemiologia , Adulto Jovem
17.
J Am Coll Cardiol ; 61(10): 1027-40, 2013 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-23473408

RESUMO

Sudden cardiac death (SCD) in an athlete is a rare yet highly visible tragedy that generates significant media attention and discussion among medical personnel, sports communities, and laypersons alike. The incidence of SCD is greater in athletes compared with their nonathletic counterparts due to the increased risk associated with strenuous exercise in the context of a quiescent cardiac abnormality. Numerous structural, electrical, and acquired cardiovascular abnormalities are capable of causing SCD, many of which can be identified during life and managed by lifestyle modifications, pharmacotherapy, and device therapy. Strategies for the prevention of SCD, including pre-participation cardiovascular screening, are endorsed by sports governing bodies, but mandatory pre-participation cardiovascular screening remains rare. Evaluation of athletes poses diagnostic difficulties, particularly differentiating between physiological adaptation to exercise, known as athlete's heart, and cardiomyopathic processes capable of causing SCD. This paper provides a detailed review regarding the etiology of SCD in young athletes and provides insight into the challenges and dilemmas faced when evaluating athletes for underlying pathological conditions.


Assuntos
Atletas , Morte Súbita Cardíaca/prevenção & controle , Algoritmos , População Negra , Cardiomiopatia Hipertrófica/diagnóstico , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Diagnóstico Diferencial , Ecocardiografia , Eletrocardiografia , Cardiopatias/complicações , Cardiopatias/diagnóstico , Humanos , Prevenção Primária , Prevenção Secundária , Medicina Esportiva , Função Ventricular Esquerda/fisiologia
18.
Heart Rhythm ; 10(2): 247-54, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23089898

RESUMO

BACKGROUND: Early repolarization (ER) in the inferior electrocardiogram leads is associated with idiopathic ventricular fibrillation, but the majority of subjects with ER have a benign prognosis. At present, there are no risk stratifiers for asymptomatic ER. OBJECTIVE: To examine the response to ajmaline provocation and exercise in potentially high-risk subjects with ER and without a definitive cardiac diagnosis. METHODS: Electrocardiographic data were reviewed for ER at baseline and during ajmaline and exercise testing in 229 potentially high-risk patients (mean age 37.7±14.9 years; 55.9% men). ER was defined as J-point elevation in ≥2 consecutive leads and stratified by type, territory, J-point height, and ST-segment morphology. RESULTS: Baseline ER was present in 26 (11.4%; 19 men) patients. During ajmaline provocation and exercise, there were no new ER changes. ER with rapidly ascending ST-segment and lateral ER consistently diminished. There were 7 patients with persistent ER during ajmaline and/or exercise. They were all men with inferior or inferolateral ER and horizontal/descending ST segment. Those with persistent ER during exercise were more likely to have a history of unexplained syncope than those in whom ER changes diminished (P<.01). Subtle nondiagnostic structural abnormalities were demonstrated in 3 of these patients. CONCLUSIONS: ER with horizontal/descending ST-segment morphology in the inferior or inferolateral leads that persists during exercise is more common in patients with prior unexplained syncope and may identify patients at higher risk of arrhythmic events. ER that persists during ajmaline provocation and/or exercise may reflect underlying subtle structural abnormalities and should prompt further investigation.


Assuntos
Ajmalina , Eletrocardiografia/métodos , Tolerância ao Exercício/fisiologia , Sistema de Condução Cardíaco/fisiopatologia , Fibrilação Ventricular/diagnóstico , Adulto , Estudos de Coortes , Teste de Esforço/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto Jovem
19.
Heart ; 99(6): 401-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23393084

RESUMO

OBJECTIVE: To investigate the prevalence and significance of increased left ventricular (LV) trabeculation in highly trained athletes. DESIGN: Cross sectional echocardiographic study. SETTING: Sports cardiology institutions in the UK and France. SUBJECTS: 1146 athletes aged 14-35 years (63.3% male), participating in 27 sporting disciplines, and 415 healthy controls of similar age. The results of athletes fulfilling conventional criteria for LV non-compaction (LVNC) were compared with 75 patients with LVNC. MAIN OUTCOME MEASURE: Number of athletes with increased LV trabeculation and the number fulfilling criteria for LVNC. RESULTS: Athletes displayed a higher prevalence of increased LV trabeculation compared with controls (18.3% vs 7.0%; p ≤ 0.0001) and 8.1% athletes fulfilled conventional criteria for LVNC. Increased LV trabeculation were more common in athletes of African/Afro-Caribbean origin. A small proportion of athletes (n = 10; 0.9%) revealed reduced systolic function and marked repolarisation changes in association with echocardiographic criteria for LVNC raising the possibility of an underlying cardiomyopathy. Follow-up during the ensuing 48.6 ± 14.6 months did not reveal adverse events. CONCLUSIONS: A high proportion of young athletes exhibit conventional criteria for LVNC highlighting the non-specific nature of current diagnostic criteria if applied to elite athletic populations. Further assessment of such athletes should be confined to the small minority that demonstrate low indices of systolic function and marked repolarisation changes.


Assuntos
Atletas , Ecocardiografia , Eletrocardiografia , Tolerância ao Exercício/fisiologia , Disfunção Ventricular Esquerda/epidemiologia , Função Ventricular Esquerda/fisiologia , Adolescente , Adulto , Estudos Transversais , Feminino , França/epidemiologia , Humanos , Masculino , Prevalência , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Reino Unido/epidemiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Adulto Jovem
20.
Heart ; 98(16): 1194-200, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22773610

RESUMO

Cardiac adaptation to intense physical exercise is determined by factors including age, gender, body size, sporting discipline and ethnicity. Differentiating physiology from pathological conditions such as hypertrophic cardiomyopathy (HCM) is challenging, but relevant, as HCM remains the commonest cause of sudden death in young athletes. Marked electrocardiographic repolarisation changes and echocardiographic left ventricular hypertrophy have been demonstrated in athletes of black ethnicity. Such changes highlight the overlap between 'athlete's heart' and morphologically mild HCM with potential for false-positive diagnoses and disqualification from competitive sport. The focus of this article is to provide practical considerations in differentiating physiological adaptation to exercise from cardiac pathology in athletes of black ethnicity.


Assuntos
População Negra , Cardiomegalia/diagnóstico , Cardiomegalia/etnologia , Cardiomiopatia Hipertrófica/diagnóstico , Cardiomiopatia Hipertrófica/etnologia , Exercício Físico , Miocárdio/patologia , Adaptação Fisiológica , Adolescente , Adulto , Fatores Etários , Cardiomegalia/mortalidade , Cardiomegalia/fisiopatologia , Cardiomiopatia Hipertrófica/mortalidade , Cardiomiopatia Hipertrófica/fisiopatologia , Morte Súbita Cardíaca/etnologia , Morte Súbita Cardíaca/prevenção & controle , Diagnóstico Diferencial , Ecocardiografia , Eletrocardiografia , Reações Falso-Positivas , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Fatores Sexuais , Adulto Jovem
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