RESUMO
OBJECTIVES: Assuming that autoimmune congenital heart block (CHB) is a progressive disease amenable to therapeutic modulation, we introduced a surveillance program for at-risk pregnancies with the dual aim of investigating if fetal atrioventricular block (AVB) could be detected and treated before becoming complete and irreversible, and to establish the incidence of AVB I, II and III in a large prospective cohort. METHODS: This was a prospective study of 212 anti-Ro52 antibody-exposed pregnancies at risk of fetal AVB that were followed weekly between 18 and 24 weeks' gestation at our tertiary fetal cardiology center from 2000 to 2015. A 12-lead electrocardiogram (ECG) was recorded within 1 week after birth. Fetal Doppler atrioventricular (AV) intervals were converted to Z-scores using reference standard values derived from normal pregnancies. Each fetus was represented by the average value of the two recordings, obtained at two consecutive visits, which resulted in the longest AV interval. AV interval values were classified into normal AV conduction (Z-score ≤ 2.0) and three levels of delayed AV conduction: Z-score > 2.0 and ≤ 3.0, Z-score > 3.0 and ≤ 4.0, and Z-score > 4.0. RESULTS: AVB II or III developed in 6/204 (2.9%) pregnancies without a CHB history and 1/8 (12.5%) of those with a CHB history. AV intervals > 2 and ≤ 3, > 3 and ≤ 4, and > 4 were detected in 16.0%, 7.5% and 2.8% of cases, respectively, and were related to the PR interval on 185 available ECGs. Three of the five cases with AVB III and one of two cases with 2:1 AVB II developed within 1 week of AV interval Z-score of 1.0, 1.9, 2.8 and 1.9, respectively. Transplacental treatment with betamethasone was associated with restoration of 1:1 AV conduction in the two fetuses with AVB II, with a better long-term result (normal ECG vs AVB I or II) observed in the case in which treatment was started within 1 week after AVB developed. Betamethasone treatment did not reverse AVB III, although a temporary effect on AV conduction was observed in 1/5 cases. Notably, the three cases in which treatment was started within 1 week after AVB III development responded with a higher ventricular rate than the other two cases and did not require pacemaker implantation until a later age (2-5 years vs 1.5-2 months). CONCLUSION: Fetal AV interval is a poor predictor of CHB progression, but CHB surveillance still allows detection of fetuses with AVB II or III shortly after its development, allowing for timely treatment initiation and potentially better outcome. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
Assuntos
Bloqueio Atrioventricular/prevenção & controle , Ecocardiografia/métodos , Coração Fetal/diagnóstico por imagem , Feto/diagnóstico por imagem , Bloqueio Cardíaco/congênito , Bloqueio Atrioventricular/classificação , Bloqueio Atrioventricular/epidemiologia , Bloqueio Atrioventricular/fisiopatologia , Autoanticorpos , Doenças Autoimunes/sangue , Doenças Autoimunes/tratamento farmacológico , Betametasona/administração & dosagem , Betametasona/uso terapêutico , Ecocardiografia Doppler/métodos , Feminino , Coração Fetal/fisiopatologia , Feto/patologia , Idade Gestacional , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Bloqueio Cardíaco/diagnóstico , Bloqueio Cardíaco/imunologia , Bloqueio Cardíaco/fisiopatologia , Humanos , Incidência , Lactente , Recém-Nascido , Gravidez/sangue , Gravidez/imunologia , Estudos Prospectivos , Resultado do TratamentoRESUMO
OBJECTIVES: Color tissue Doppler imaging (cTDI) is a promising tool for the assessment of fetal cardiac function. However, the analysis of myocardial velocity traces is cumbersome and time-consuming, limiting its application in clinical practice. The aim of this study was to evaluate fetal cardiac function during the second half of pregnancy and to develop reference ranges using an automated method to analyze cTDI recordings from a cardiac four-chamber view. METHODS: This was a cross-sectional study including 201 normal singleton pregnancies between 18 and 42 weeks of gestation. During fetal echocardiography, a four-chamber view of the heart was visualized and cTDI was performed. Regions of interest were positioned at the level of the atrioventricular plane in the left ventricular (LV), right ventricular (RV) and septal walls of the fetal heart, to obtain myocardial velocity traces that were analyzed offline using the automated algorithm. Peak myocardial velocities during atrial contraction (Am), ventricular ejection (Sm) and rapid ventricular filling, i.e. early diastole (Em), as well as the Em/Am ratio, mechanical cardiac time intervals and myocardial performance index (cMPI) were evaluated, and gestational age-specific reference ranges were constructed. RESULTS: At 18 weeks of gestation, the peak myocardial velocities, presented as fitted mean with 95% CI, were: LV Am, 3.39 (3.09-3.70) cm/s; LV Sm, 1.62 (1.46-1.79) cm/s; LV Em, 1.95 (1.75-2.15) cm/s; septal Am, 3.07 (2.80-3.36) cm/s; septal Sm, 1.93 (1.81-2.06) cm/s; septal Em, 2.57 (2.32-2.84) cm/s; RV Am, 4.89 (4.59-5.20) cm/s; RV Sm, 2.31 (2.16-2.46) cm/s; and RV Em, 2.94 (2.69-3.21) cm/s. At 42 weeks of gestation, the peak myocardial velocities had increased to: LV Am, 4.25 (3.87-4.65) cm/s; LV Sm, 3.53 (3.19-3.89) cm/s; LV Em, 4.55 (4.18-4.94) cm/s; septal Am, 4.49 (4.17-4.82) cm/s; septal Sm, 3.36 (3.17-3.55) cm/s; septal Em, 3.76 (3.51-4.03) cm/s; RV Am, 6.52 (6.09-6.96) cm/s; RV Sm, 4.95 (4.59-5.32) cm/s; and RV Em, 5.42 (4.99-5.88) cm/s. The mechanical cardiac time intervals generally remained more stable throughout the second half of pregnancy, although, with increased gestational age, there was an increase in duration of septal and RV atrial contraction, LV pre-ejection and septal and RV ventricular ejection, while there was a decrease in duration of septal postejection. Regression equations used for the construction of gestational age-specific reference ranges for peak myocardial velocities, Em/Am ratios, mechanical cardiac time intervals and cMPI are presented. CONCLUSION: Peak myocardial velocities increase with gestational age, while the mechanical time intervals remain more stable throughout the second half of pregnancy. Using an automated method to analyze cTDI-derived myocardial velocity traces, it was possible to construct reference ranges, which could be used in distinguishing between normal and abnormal fetal cardiac function. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Coração Fetal/diagnóstico por imagem , Ultrassonografia Doppler em Cores/instrumentação , Adulto , Algoritmos , Estudos Transversais , Ecocardiografia Doppler/métodos , Feminino , Coração Fetal/fisiologia , Feto , Idade Gestacional , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Recém-Nascido , Gravidez , Valores de ReferênciaRESUMO
OBJECTIVE: To evaluate the feasibility of automated analysis of fetal myocardial velocity recordings obtained by color tissue Doppler imaging (cTDI). METHODS: This was a prospective cross-sectional observational study of 107 singleton pregnancies ≥ 41 weeks of gestation. Myocardial velocity recordings were obtained by cTDI in a long-axis four-chamber view of the fetal heart. Regions of interest were placed in the septum and the right (RV) and left (LV) ventricular walls at the level of the atrioventricular plane. Peak myocardial velocities and mechanical cardiac time intervals were measured both manually and by an automated algorithm and agreement between the two methods was evaluated. RESULTS: In total, 321 myocardial velocity traces were analyzed using each method. It was possible to analyze all velocity traces obtained from the LV, RV and septal walls with the automated algorithm, and myocardial velocities and cardiac mechanical time intervals could be measured in 96% of all traces. The same results were obtained when the algorithm was run repeatedly. The myocardial velocities measured using the automated method correlated significantly with those measured manually. The agreement between methods was not consistent and some cTDI parameters had considerable bias and poor precision. CONCLUSIONS: Automated analysis of myocardial velocity recordings obtained by cTDI was feasible, suggesting that this technique could simplify and facilitate the use of cTDI in the evaluation of fetal cardiac function, both in research and in clinical practice. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
Assuntos
Ecocardiografia Doppler em Cores , Coração Fetal/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Velocidade do Fluxo Sanguíneo , Estudos Transversais , Feminino , Coração Fetal/fisiologia , Humanos , Interpretação de Imagem Assistida por Computador , Recém-Nascido , Masculino , Reconhecimento Automatizado de Padrão , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Estudos ProspectivosRESUMO
Congenital heart block (CHB) is a potentially lethal condition characterized by a third-degree atrioventricular block (AVB). Despite anti-Ro52 antibodies being detected in nearly 90% of mothers of affected children, CHB occurs in only 1-2% of anti-Ro/Sjögren's-syndrome-related antigen A (SSA) autoantibody-positive pregnancies. Maternal antibodies have been suggested to bind molecules crucial to fetal cardiac function; however, it remains unknown whether a single antibody profile associates with CHB or whether several specificities and cross-reactive targets exist. Here, we aimed to define further the reactivity profile of CHB-associated antibodies towards Ro52p200 (amino acid 200-239). We first analysed reactivity of a monoclonal anti-Ro52 antibody shown to induce AVB in rats (7.8C7) and of sera from anti-Ro52p200 antibody-positive mothers of children with CHB towards a panel of modified Ro52p200 peptides, and subsequently evaluated their potential to induce AVB in rats upon transfer during gestation. We observed that CHB maternal sera displayed a homogeneous reactivity profile targeting preferentially the C-terminal part of Ro52p200, in contrast to 7.8C7 that specifically bound the p200 N-terminal end. In particular, amino acid D233 appeared crucial to maternal antibody reactivity towards p200. Despite low to absent reactivity towards rat p200 and different binding profiles towards mutated rat peptides indicating recognition of different epitopes within Ro52p200, immunoglobulin (Ig)G purified from two mothers of children with CHB could induce AVB in rats. Our findings support the hypothesis that several fine antibody specificities and cross-targets may exist and contribute to CHB development in anti-Ro52 antibody-positive pregnancies.
Assuntos
Epitopos/imunologia , Bloqueio Cardíaco/congênito , Sistema de Condução Cardíaco , Ribonucleoproteínas/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Criança , Pré-Escolar , Modelos Animais de Doenças , Epitopos/química , Feminino , Bloqueio Cardíaco/diagnóstico , Bloqueio Cardíaco/imunologia , Humanos , Imunoglobulina G/imunologia , Fragmentos de Peptídeos/imunologia , Ligação Proteica/imunologia , Ratos , Ribonucleoproteínas/químicaRESUMO
OBJECTIVE: Congenital heart block (CHB) may develop in fetuses of women with anti-Ro/SSA autoantibodies, and carries substantial morbidity and mortality. The aim was to evaluate how information on CHB is imparted and identify areas of improvement. METHODS: A questionnaire was distributed to anti-Ro/SSA antibody-positive women who had either participated in a surveillance programme but whose expected child did not develop CHB (n = 100, denoted Doppler-Assessed Pregnancies (DAP) group) or given birth to a child with CHB (n = 88, denoted CHB-Affected Pregnancies (CAP) group). RESULTS: The response rate was 83% (157/188). Most women received the information on CHB when they were already pregnant (DAP group 60%, CAP group 83%). However, a majority of them would have wanted the information before pregnancy (DAP group 52%, CAP group 56%), and most stated that it would not have influenced their decision to have a child (DAP group 77%, CAP group 58%). The ability to both understand the information and to perceive the information as sufficient were significantly higher when someone trained in paediatric cardiology gave the information. CONCLUSIONS: Our findings indicate that information on CHB should be given to women before pregnancy. The data further highlight the importance of having specific knowledge for giving relevant and understandable, yet sufficient information.
Assuntos
Anticorpos Antinucleares/sangue , Doenças Autoimunes/complicações , Conhecimentos, Atitudes e Prática em Saúde , Bloqueio Cardíaco/congênito , Educação de Pacientes como Assunto , Assistência Perinatal/métodos , Acesso à Informação , Adulto , Doenças Autoimunes/sangue , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/imunologia , Biomarcadores/sangue , Compreensão , Ecocardiografia Doppler , Feminino , Bloqueio Cardíaco/diagnóstico por imagem , Bloqueio Cardíaco/etiologia , Humanos , Pessoa de Meia-Idade , Gravidez , Medição de Risco , Fatores de Risco , Inquéritos e Questionários , Ultrassonografia Pré-Natal , Adulto JovemRESUMO
OBJECTIVE: The risk for congenital heart block (CHB) associated with maternal Ro/SSA autoantibodies is low, but the possibility of treating early stages of disease has seen the introduction of Doppler echocardiographic surveillance programs with serial examinations during the CHB susceptibility weeks of pregnancy. The aim of the present study was to understand how Ro/SSA autoantibody-positive women having undergone Doppler echocardiographic surveillance programs and giving birth to children without CHB experienced their pregnancy and frequent ultrasound examinations. METHODS: A validated questionnaire based on data from an interview-study was distributed to Ro/SSA-positive women supervised with Doppler examinations during their pregnancy (n = 100). RESULTS: The response rate was 79%. The majority of the women (61%) reported that the increased number of ultrasound examinations influenced their pregnancy, but in a positive way, with qualified information and additional support from health care personnel in conjunction with the examinations. Further, the visits to the clinic provided opportunities to see the ultrasound picture of the expected infant. However, one-third of the women also reported stress in relation to the examinations. CONCLUSIONS: Fetal echocardiographic surveillance holds many and predominantly positive effects for Ro/SSA-positive women during pregnancy in addition to the medical advantages.
Assuntos
Autoanticorpos/imunologia , Autoantígenos/imunologia , Ecocardiografia Doppler/métodos , Bloqueio Cardíaco/congênito , Complicações na Gravidez/imunologia , RNA Citoplasmático Pequeno/imunologia , Ribonucleoproteínas/imunologia , Ultrassonografia Pré-Natal/métodos , Adulto , Criança , Ecocardiografia Doppler/psicologia , Feminino , Bloqueio Cardíaco/diagnóstico por imagem , Bloqueio Cardíaco/imunologia , Humanos , Recém-Nascido , Pessoa de Meia-Idade , Gravidez , Complicações na Gravidez/diagnóstico por imagem , Síndrome de Sjogren/diagnóstico , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: The main aim of this study was to identify foetal susceptibility genes on chromosome six for Ro/SSA autoantibody-mediated congenital heart block. SUBJECTS AND DESIGN: Single nucleotide polymorphism (SNP) genotyping of individuals in the Swedish Congenital Heart Block (CHB) study population was performed. Low-resolution HLA-A, -Cw and -DRB1 allele typing was carried out in 86 families comprising 339 individuals (86 Ro/SSA autoantibody-positive mothers, 71 fathers, 87 CHB index cases and 95 unaffected siblings). RESULTS: A case-control comparison between index cases and population-based out-of-study controls (n = 1710) revealed association of CHB with 15 SNPs in the 6p21.3 MHC locus at a chromosome-wide significance of P < 2.59 × 10(-6) (OR 2.21-3.12). In a family-based analysis of association of SNP markers as well as distinct MHC class I and II alleles with CHB, HLA-DRB1*04 and HLA-Cw*05 variants were significantly more frequently transmitted to affected individuals (P < 0.03 and P < 0.05, respectively), whilst HLA-DRB1*13 and HLA-Cw*06 variants were significantly less often transmitted to affected children (P < 0.04 and P < 0.03). We further observed marked association of increased paternal (but not maternal) HLA-DRB1*04 transmission to affected offspring (P < 0.02). CONCLUSIONS: HLA-DRB1*04 and HLA-Cw*05 were identified as novel foetal HLA allele variants that confer susceptibility to CHB in response to Ro/SSA autoantibody exposure, whilst DRB1*13 and Cw*06 emerged as protective alleles. Additionally, we demonstrated a paternal contribution to foetal susceptibility to CHB for the first time.
Assuntos
Antígenos HLA-C/genética , Cadeias HLA-DRB1/genética , Bloqueio Cardíaco/congênito , Adulto , Anticorpos Antinucleares , Criança , Saúde da Família , Pai , Feminino , Frequência do Gene , Genes MHC da Classe II/genética , Predisposição Genética para Doença , Bloqueio Cardíaco/epidemiologia , Bloqueio Cardíaco/genética , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Suécia/epidemiologiaRESUMO
OBJECTIVE: To distinguish between blocked atrial bigeminy (BB) and incomplete atrioventricular block with 2:1 conduction (2:1 AVB) can be very difficult, especially in the mid-term fetus. Making a correct diagnosis has important clinical implications, as their prognosis and management differ markedly. Our objective was to investigate whether analysis of isovolumetric time intervals could improve Doppler echocardiography in differentiating these conditions. METHODS: Sixteen fetuses with sustained BB or isolated 2:1 AVB, diagnosed at our tertiary center from 2002 to 2012, were reviewed retrospectively. Doppler recordings of left ventricular in- and outflow, including mitral and aortic valve movements, were used to measure isovolumetric contraction (ICT) and relaxation (IRT) time intervals. ICT reference values obtained from 104 normal pregnancies were used for comparison. RESULTS: Ten fetuses had BB and six 2:1 AVB. Five of the AVB cases were anti-Ro antibody positive and one had long QT syndrome (LQTS). ICT was systematically shorter in BB than in antibody-mediated 2:1 AVB. Nine of 10 cases with BB had an ICT below -2 SD and the five with antibody-mediated 2:1 AVB had values at or above +2 SD. All 15 fetuses with either BB or antibody-mediated AVB had an IRT of < 70 ms, as opposed to a markedly prolonged IRT (105 ms) in the LQTS case. CONCLUSION: Measurement of ICT can improve the differential diagnosis between BB and antibody-mediated 2:1 AVB. Fetuses with BB or antibody-mediated AVB are unlikely to have IRT measurements exceeding 70 ms and, when this is observed, LQTS should be considered a more likely diagnosis.
Assuntos
Complexos Atriais Prematuros/diagnóstico por imagem , Bloqueio Atrioventricular/diagnóstico por imagem , Doenças Fetais/diagnóstico por imagem , Coração Fetal/fisiopatologia , Complexos Atriais Prematuros/fisiopatologia , Bloqueio Atrioventricular/fisiopatologia , Bradicardia/diagnóstico por imagem , Bradicardia/fisiopatologia , Diagnóstico Diferencial , Ecocardiografia , Feminino , Doenças Fetais/fisiopatologia , Feto , Frequência Cardíaca/fisiologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Gravidez , Prognóstico , Estudos Retrospectivos , Ultrassonografia Doppler de PulsoRESUMO
The objective of the study was to investigate the antigen specificity and occurrence of individual autoantibodies in mothers of children diagnosed with atrioventricular (AV) block in a nation-wide setting. Patients with AV block detected before 15 years of age were identified using national quality registries as well as a network of pediatric and adult cardiologists and rheumatologists at the six university hospitals in Sweden. Patients with gross heart malformations, surgically or infectiously induced blocks were excluded. Blood samples were obtained from the mothers and maternal autoantibody profile, including the occurrence of antibodies against Ro52, Ro60, La, SmB, SmD, RNP-70k, RNP-A, RNP-C, CENP-C, Scl-70, Jo-1, ribosomal RNP and histones was investigated in 193 mothers of children with AV block by immunoblotting and ELISA. Autoantibody reactivity was detected in 48% (93/193) of the mothers of children with AV block. In autoantibody-positive mothers, the vast majority, 95% (88/93), had antibodies against Ro52, while 63% (59/93) had autoantibodies to Ro60 and 58% (54/93) had autoantibodies to La. In addition, 13% (12/93) of the autoantibody-positive mothers had antibodies to other investigated antigens besides Ro52, Ro60 and La, and of these anti-histone antibodies were most commonly represented, detected in 8% (7/93) of the mothers. In conclusion, this Swedish population-based study confirms that maternal autoantibodies may associate with heart block in the child. Further, our data demonstrate a dominant role of Ro52 antibodies in association with AV block.
Assuntos
Bloqueio Atrioventricular/epidemiologia , Bloqueio Atrioventricular/imunologia , Doenças Autoimunes , Filho de Pais com Deficiência , Mães , Grupos Populacionais , Adolescente , Bloqueio Atrioventricular/sangue , Bloqueio Atrioventricular/complicações , Autoanticorpos/sangue , Autoanticorpos/imunologia , Criança , Filho de Pais com Deficiência/estatística & dados numéricos , Pré-Escolar , Epitopos/imunologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mães/estatística & dados numéricos , Grupos Populacionais/estatística & dados numéricos , Prevalência , SuéciaRESUMO
OBJECTIVE: Fetal bradyarrhythmias have various underlying mechanisms. As blocked atrial bigeminy (BB) generally resolves spontaneously, but incomplete atrioventricular block (AVB) might respond to steroid treatment, correct diagnosis is of major importance. Our objectives were to assess the underlying mechanisms in fetal bradyarrhythmia and the accuracy of Doppler techniques in differentiating between them. METHODS: Seventy-eight patients referred to our tertiary center between 1990 and 2007 for evaluation of fetal bradycardia were analyzed retrospectively. Besides Doppler recordings from the mitral valve/aorta, superior vena cava/aorta and pulmonary vein/peripheral pulmonary artery, we used recordings from the pulmonary trunk and ductus venosus. We calculated the ratio of the time interval between conducted and consecutive blocked atrial contractions divided by the interval between two conducted atrial beats (a(cb) /a(cc) ), to analyze more meticulously the atrial rhythm in BB and second-degree AVB. RESULTS: Fetal bradycardia ( ≤ 110 bpm) was confirmed in 65 of the 78 referred cases. Twenty-five had AVB (of which 20 were complete AVB), 29 had BB (of which 23 were intermittent) and 11 had sinus bradycardia. The bradyarrhythmic mechanism was identified correctly in all but one fetus with an atrial ectopic rhythm. Heart rates < 65 bpm were not seen in fetuses diagnosed with BB and rates < 60 bpm were seen only in cases with complete AVB, but heart rate did not distinguish between BB and AVB in the 60-75 bpm range. The a(cb) /a(cc) ratio clearly differentiated between fetsues with BB and those with second-degree AVB, including during midgestation, when it was difficult to distinguish these fetuses. CONCLUSIONS: Using Doppler flow recordings, the mechanism causing fetal bradycardia can be clarified. In most cases this can be accomplished by visual validation only, and meticulous measurements are needed mainly to distinguish midterm fetuses with BB from those with second-degree AVB.
Assuntos
Bloqueio Atrioventricular/diagnóstico por imagem , Bradicardia/diagnóstico por imagem , Ecocardiografia Doppler/métodos , Doenças Fetais/diagnóstico por imagem , Ultrassonografia Pré-Natal , Bloqueio Atrioventricular/etiologia , Bloqueio Atrioventricular/fisiopatologia , Bradicardia/etiologia , Bradicardia/fisiopatologia , Feminino , Doenças Fetais/fisiopatologia , Humanos , Contração Miocárdica/fisiologia , Gravidez , Estudos RetrospectivosRESUMO
Foetal echocardiographic ultrasound techniques still remain the dominating modality for diagnosing foetal atrioventricular block (AVB). Foetal electrocardiography might become a valuable tool to measure time intervals, but magnetocardiography is unlikely to get a place in clinical practice. Assuming that AVB is a gradually progressing and preventable disease, starting during a critical period in mid-gestation with a less abnormal atrioventricular conduction before progressing to a complete irreversible AVB (CAVB), echocardiographic methods to detect first-degree AVB have been developed. The time intervals obtained with these techniques are all based on the identification of mechanical or hemodynamic events as markers of atrial (A) and ventricular (V) depolarizations and will accordingly include both electrical and mechanical components. Prospective observational studies have demonstrated a transient prolongation of AV time intervals in anti-Ro/SSA antibody-exposed foetuses, but it has not succeeded to identify a degree of AV time prolongation predicting irreversible cardiac damage and progression to CAVB. Causes of sustained bradycardia include CAVB, 2:1 AVB, sinus bradycardia and blocked atrial bigeminy (BAB). Using foetal echocardiographic techniques and a systematic approach, a correct diagnosis can be made in almost every case. Sinus bradycardia and CAVB are usually easy to diagnose, but BAB has a tendency to be sustained and shows a high degree of resemblance with 2:1 AVB when diagnosed during mid-gestational. As BAB resolves without treatment and 2:1 AVB may respond to treatment with fluorinated steroids, a correct diagnosis becomes an issue of major importance to avoid unnecessary treatment of harmless and spontaneously reversing conditions.
Assuntos
Bloqueio Atrioventricular/congênito , Bloqueio Atrioventricular/diagnóstico , Doenças Fetais/diagnóstico , Bloqueio Atrioventricular/classificação , Bloqueio Atrioventricular/fisiopatologia , Ecocardiografia Doppler/métodos , Doenças Fetais/classificação , Doenças Fetais/fisiopatologia , Testes de Função Cardíaca/métodos , HumanosRESUMO
OBJECTIVE: To investigate the diagnostic precision of three Doppler methods in their ability to predict postnatal first-degree atrioventricular (AV) block. METHODS: This was a prospective, observational study carried out from December 1999 to March 2008, including 95 fetuses of anti-SSA/Ro positive mothers undergoing weekly fetal echocardiograms at 18-24 weeks' gestation. Doppler-derived AV time intervals for left ventricular inflow (MV), inflow and outflow (MV-Ao) and superior vena cava a-wave to aortic flow (SVC-Ao) were compared with the PR interval on postnatal electrocardiography. Reference values for MV intervals were established from 102 healthy fetuses, with previously published reference ranges used for the two other methods. Bayesian and receiver-operating characteristics (ROC) curve analyses were performed. RESULTS: The prevalence of first-degree AV block at birth was 13.8%. Using a cut-off at the upper 95% confidence limit, MV-Ao and SVC-Ao time intervals had a sensitivity of 91.7%, and negative predictive value and negative likelihood ratio of 98.4% and 0.10, respectively. The corresponding positive predictive value/positive likelihood ratio for MV-Ao and SVC-Ao were 42.3%/4.5 and 47.8%/5.7, respectively. The areas under the ROC curve (AUC) for MV-Ao and SVC-Ao were 0.87 and 0.89, respectively (both P < 0.001), with generated cut-offs for abnormal AV time intervals at 134-138 and 132-138 ms. MV time intervals using a cut-off at the upper 95% confidence limit had a sensitivity of just 50% and an AUC of 0.74 (P < 0.01). CONCLUSION: The MV-Ao and SVC-Ao Doppler methods make it possible to identify nearly all fetuses with first-degree AV block at birth and to exclude conduction disturbances in the case of a normal AV time measurement but at the cost of a positive predictive value of 50%.
Assuntos
Bloqueio Atrioventricular/diagnóstico por imagem , Ecocardiografia Doppler/métodos , Frequência Cardíaca Fetal/fisiologia , Bloqueio Atrioventricular/embriologia , Bloqueio Atrioventricular/fisiopatologia , Ecocardiografia Doppler/normas , Feminino , Humanos , Gravidez , Estudos Prospectivos , Curva ROC , Valores de Referência , Ultrassonografia Pré-NatalRESUMO
OBJECTIVE: To investigate if anti-Ro/SSA antibody-exposed fetuses with prolonged atrioventricular (AV) time intervals also have prolongation of the isovolumetric contraction time (ICT). METHODS: Seventy-eight anti-Ro/SSA (including 70 anti-Ro52) antibody-exposed fetuses at risk for congenital heart block (CHB) were followed weekly, between 18 and 24 weeks of gestation, with two Doppler echocardiographic methods designed to detect signs of first-degree AV block. One of these AV time measurements, using hemodynamic events from the mitral valve and aortic outflow as indirect markers of atrial and ventricular depolarization (MV-Ao), was also used to calculate a time interval representing an early phase of systolic cardiac performance, i.e. the ICT. Two hundred and eighty-four women with normal pregnancies served as controls for AV time intervals and another 106 were used to establish an ICT reference range. RESULTS: Strong positive relationships were found between ICT and MV-Ao time intervals (r = 0.91, P < 0.001), as well as between ICT and time intervals obtained from the superior vena cava and aorta (r = 0.85, P < 0.001). The ICT was estimated to contribute more than 50% of the total AV time prolongation. Abnormal AV time and ICT intervals were only seen in anti-Ro52 positive pregnancies. CONCLUSIONS: The ICT is an important contributor to prolongation of AV time intervals. This observation suggests that anti-Ro52/SSA antibody-exposed fetal hearts have not only disturbed electrical conduction but also decreased mechanical performance. Moreover, our findings have implications for the interpretation of AV time intervals used for surveillance of fetuses at risk for developing CHB.
Assuntos
Anticorpos Antinucleares , Bloqueio Atrioventricular/imunologia , Frequência Cardíaca Fetal/imunologia , Troca Materno-Fetal/imunologia , Contração Miocárdica/imunologia , Bloqueio Atrioventricular/congênito , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/fisiopatologia , Feminino , Coração Fetal/diagnóstico por imagem , Coração Fetal/fisiopatologia , Idade Gestacional , Frequência Cardíaca Fetal/fisiologia , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Contração Miocárdica/fisiologia , Gravidez , Complicações na Gravidez/imunologia , Fatores de Risco , Ultrassonografia Pré-NatalRESUMO
AIM: To perform a 10-year follow up of cardiac structure and function after twin-to-twin transfusion syndrome (TTTS)--a severe foetal circulatory complication associated with myocardial hypertrophy in the recipient twin. METHODS: Cardiac dimensions, systolic and diastolic function as assessed by echocardiography including flow and tissue Doppler velocimetry in 22 healthy survivors of TTTS with a mean age of 9.6 (7.2-11.8) years. RESULTS: The donor and recipient twin did not show any differences in end-diastolic ventricular size, interventricular septum thickness, diameter of right ventricular outflow tract, cardiac valves, coronary arteries or in systolic blood flow velocities. However, compared with the donors, the recipients had significantly lower E/A ratios because of lower E-waves in both mitral (-0.15 +/- 0.10, p < 0.01) and tricuspid (-0.09 +/- 0.07, p < 0.01) valves, indicating reduced early diastolic ventricular fillings compared with donors. CONCLUSION: At school age, twins surviving TTTS had a cardiac structure and function within normal range. There were no differences in heart structure or systolic ventricular function between twins but, compared with the donor twin, we found a reduced early diastolic function in the recipient.
Assuntos
Transfusão Feto-Fetal/complicações , Miocárdio/patologia , Disfunção Ventricular/etiologia , Função Ventricular , Velocidade do Fluxo Sanguíneo , Criança , Estudos de Coortes , Diástole/fisiologia , Ecocardiografia , Feminino , Seguimentos , Humanos , Hipertrofia/etiologia , Masculino , Gravidez , Gêmeos Monozigóticos , Disfunção Ventricular/diagnóstico por imagemRESUMO
Maternal autoantibodies to the p200-epitope of Ro52 have been suggested to correlate with development of congenital heart block. The aim of the present study was to evaluate the clinical relevance and predictive value of p200-antibodies in high-risk pregnancies. Sera from 515 Finnish, Swedish and American women were included in the study. Sera originated from 202 mothers with an infant affected by second- or third-degree atrioventricular block (AVB), 177 mothers with rheumatic disease having infants with normal heart rate and female blood donors (n = 136). A novel serological assay for Ro52 p200-antibodies with intra- and inter-assay variability of 3% and 3.8% respectively was developed. Mothers of children affected by AVB II-III had significantly higher p200-antibody levels than mothers with rheumatic disease having children with normal heart rate (P < 0.001). In the Swedish cohort, a distinction between foetuses with normal conduction, AVB I, AVB II and III was possible. A significant difference in anti-p200 levels between AVB I and AVB II-III groups compared with foetuses with normal conduction (P < 0.05 and P < 0.01) was observed. Using p200-antibodies as a second step analysis in Ro52-positive pregnancies increased the positive predictive value for foetal cardiac involvement (AVB I, II or III) from 0.39 (0.27-0.51) to 0.53 (0.37-0.68). In conclusion, Ro52 p200-antibodies may occur in women with unaffected children, but levels are significantly higher in mothers of children with congenital heart block and are suggested as a relevant marker in evaluating the risk for foetal AV block.
Assuntos
Autoanticorpos/sangue , Proteínas Ativadoras de GTPase/imunologia , Bloqueio Cardíaco/congênito , Bloqueio Cardíaco/imunologia , Ribonucleoproteínas/química , Adulto , Análise de Variância , Bloqueio Atrioventricular/imunologia , Autoanticorpos/imunologia , Biomarcadores/sangue , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Finlândia , Humanos , Gravidez , Fatores de Risco , Suécia , Estados UnidosRESUMO
OBJECTIVE: Fetuses exposed to anti-SSA (Sjögren's) antibodies are at risk of developing irreversible complete atrioventricular block (CAVB), resulting in death or permanent cardiac pacing. Anti-inflammatory treatment during the transition period from normal heart rhythm (fetal heart rhythm (FHR)) to CAVB (emergent CAVB) can restore sinus rhythm, but detection of emergent CAVB is challenging, because it can develop in ⩽24 h. We tested the feasibility of a new technique that relies on home FHR monitoring by the mother, to surveil for emergent CAVB. STUDY DESIGN: We recruited anti-SSA-positive mothers at 16 to 18 weeks gestation (baseline) from 8 centers and instructed them to monitor FHR two times a day until 26 weeks, using a Doppler device at home. FHR was also surveilled by weekly or every other week fetal echo. If FHR was irregular, the mother underwent additional fetal echo. We compared maternal stress/anxiety before and after monitoring. Postnatally, infants underwent a 12-lead electrocardiogram. RESULTS: Among 133 recruited, 125 (94%) enrolled. Among those enrolled, 96% completed the study. Reasons for withdrawal (n=5) were as follows: termination of pregnancy, monitoring too time consuming or moved away. During home monitoring, 9 (7.5%) mothers detected irregular FHR diagnosed by fetal echo as normal (false positive, n=2) or benign atrial arrhythmia (n=7). No CAVB was undetected or developed after monitoring. Questionnaire analysis indicated mothers felt comforted by the experience and would monitor again in future pregnancies. CONCLUSION: These data suggest ambulatory FHR surveillance of anti-SSA-positive pregnancies is feasible, has a low false positive rate and is empowering to mothers.
Assuntos
Anticorpos Antinucleares/sangue , Monitorização Fetal/métodos , Frequência Cardíaca Fetal , Ruídos Cardíacos , Cuidado Pré-Natal/métodos , Adulto , Bloqueio Atrioventricular/diagnóstico , Feminino , Idade Gestacional , Humanos , Monitorização Ambulatorial/métodos , Gravidez , Complicações na Gravidez/diagnóstico , Estudos Prospectivos , Ultrassonografia Doppler , Estados UnidosRESUMO
AIM: To verify whether extra uterine changes in total peripheral vascular resistance and cardiac output, caused by raised haematocrit, occur in fetal life and if they can be documented using conventional ultrasound techniques. METHODS: An exchange transfusion with packed red cells was performed on five fetal lambs at 140 days of gestation (weight 3.44, SD 0.48 kg); three others were used as controls. The haematocrit was raised from 44 +/- 3 to 64 (SD2)%. RESULTS: Body temperature, blood gas, and pH remained within normal limits. Blood viscosity increased from 5.3 (0.3) to 9.6 (1.6) cps. Combined cardiac output fell to 30% of its initial value. The pulsatility index (PI) remained unchanged in the umbilical artery (0.66, SD 0.1) and descending aorta (1.3, SD 0.3). A significant positive correlation was found between haematocrit and PI only in the carotid artery (r = 0.67, p < 0.01). CONCLUSION: In the fetus, as in adults, an increase in blood viscosity is associated with a fall in cardiac output. However, the low resistance and the relative inertia of the placental vascular bed blunt the velocimetric changes that could be induced in the lower body vascular system by an increase in resistance. Such changes were observed only in the carotid artery. These results could be of interest in the Doppler monitoring of human fetuses at risk of an abnormal increase in their haematocrit.