RESUMO
BACKGROUND: Management of patients treated with oral anticoagulation (OAC) requiring a cardiovascular implantable electronic device (CIED) surgery is a challenge that requires balancing the risk of bleeding complications with the risk of thromboembolic events. Recently the approach of performing these procedures while the patient remains with a therapeutic international normalized ratio has gained interest due to several publications showing its relative safety. OBJECTIVES: To evaluate the safety and effectiveness of continuous use of OAC compared with heparin bridging in the perioperative setting of CIED surgery using a meta-analysis. METHODS: A systematic review of PubMed/MEDLINE, Ovid, and Elsevier databases was performed. Eligible randomized controlled trials and cohort studies were included. The outcomes studied were risk of clinically significant bleeding and of thromboembolic events. Our analysis was restricted to OAC with vitamin K antagonists. RESULTS: Of 560 manuscripts initially considered relevant, seven were included in the meta-analysis, totaling 2,191 patients. Data are reported as odds ratios (ORs) with confidence interval (CI) of 95%. Maintenance of OAC was associated with a significantly lower risk of postoperative bleeding compared with heparin bridge (OR = 0.25, 95% CI 0.17-0.36, P < 0.00001). There was no difference noted in the risk of thromboembolic events between the two strategies (OR = 1.86, 95% CI 0.29-12.17, P = 0.57). CONCLUSIONS: Uninterrupted use of OAC in the perioperative of CIED surgery was associated with a reduced risk of bleeding. This strategy should be considered the preferred one in patients at moderate-to-high risk of thromboembolic events.
Assuntos
Anticoagulantes/administração & dosagem , Hemorragia/epidemiologia , Heparina/administração & dosagem , Implantação de Prótese/estatística & dados numéricos , Tromboembolia/epidemiologia , Tromboembolia/prevenção & controle , Administração Oral , Idoso , Comorbidade , Desfibriladores Implantáveis/estatística & dados numéricos , Feminino , Hemorragia/prevenção & controle , Humanos , Incidência , Masculino , Marca-Passo Artificial/estatística & dados numéricos , Pré-Medicação/estatística & dados numéricos , Medição de Risco , Resultado do Tratamento , Vitamina K/antagonistas & inibidoresRESUMO
BACKGROUND: Surgical pulmonary veins isolation (PVI) is done to restore sinus rhythm (SR) in patients with chronic permanent atrial fibrillation (CPAF) and mitral valve disease. Here we compare the efficacy of electrical block lines performed with radiofrequency (RF) compared with conventional surgery. METHODS: Randomized trial of 22 patients with CPAF and indication for mitral valve surgery. Ten patients underwent conventional surgery (SURG) and 12 RF. To prove the efficacy of the blockage lines, epicardial pacemaker wires were placed in the isolated pulmonary veins region (IPVR) and right atria (RA). RESULTS: There were no differences in the baseline data among the groups. All patients remained in SR during the immediate postoperative period. Block lines were tested in patients who remained in SR during the following days (eight in SURG and nine in RF). The median value of thresholds to conduct the stimulus of IPVR for the RA was 18 mA in SURG and 3 mA in RF (P < 0.022). Eight SURG patients and seven RF patients (P < 0.38) remained in SR at hospital discharge. Eleven RF patients and one SURG required amiodarone to maintain SR (P < 0.001). The incidence of recurrent atrial fibrillation (AF) in the follow-up was 10.7/100 patients/year in the SURG group versus 73.1/100 patients/year in the RF group (P = 0.009). CONCLUSIONS: PVI by SURG formed more effective block lines than RF. SR at hospital discharge was similar among the groups, but more amiodarone was used in RF. During follow-up, incidence of recurrent AF was higher in the RF group.
Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Doenças das Valvas Cardíacas/cirurgia , Valva Mitral/cirurgia , Veias Pulmonares/cirurgia , Idoso , Amiodarona/uso terapêutico , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Doença Crônica , Feminino , Doenças das Valvas Cardíacas/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do TratamentoRESUMO
BACKGROUND: Chronic atrial fibrillation (AF) due to mitral valve disease has been successfully treated by surgery. We performed a study to evaluate the effectiveness of a surgical method of simple pulmonary vein isolation (PVI) without radiofrequency or cryoablation in the restoration of sinus rhythm in a group of patients. METHODS: Fifteen patients were operated on for mitral valve disease and chronic AF. The technique consists basically of a circumferential incision excluding the pulmonary vein ostia from the left atrium. RESULTS: Sinus rhythm was achieved in 92.3% of the patients at 6-month follow-up. Echocardiograms 2 months after surgery showed a mean decrease of 1.1 cm in left atrial size. Effective atrial ejection was reestablished in all patients in whom sinus rhythm was achieved (mean LA ejection fraction 41% +/- 14%). Twenty-four hour Holter recordings did not show episodes of paroxysmal atrial fibrillation in any patients. Four patients had isolated episodes of ventricular ectopic beats. Stress electrocardiograms showed mean maximal ventricular response was 64% +/- 11% and 73% +/- 9% of predicted value at 2 and 6 months, respectively. All patients had improved NYHA functional class after surgery; 74% of patients were in NYHA functional class I at 6 months compared with 13.3% preoperatively. CONCLUSIONS: Pulmonary vein isolation without the use of radiofrequency or cryoablation is effective in restoring sinus rhythm in patients with chronic AF secondary to mitral valve disease. Based on simple surgical incisions, this technique is more advantageous than others requiring additional instrumentation.
Assuntos
Fibrilação Atrial/cirurgia , Insuficiência da Valva Mitral/cirurgia , Estenose da Valva Mitral/cirurgia , Veias Pulmonares/cirurgia , Adulto , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/etiologia , Doença Crônica , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/complicações , Estenose da Valva Mitral/complicaçõesRESUMO
OBJECTIVE: To assess the occurrence of late thromboembolism after surgical repair of chronic atrial fibrillation (AF) simultaneously with repair of mitral valve using the Cox-Maze procedure. METHODS: 69 patients underwent Cox 3 procedure, with no cryoablation simultaneously with mitral valvuloplasty or prosthesis. Mean age was 49.9+/-13.2 years. Mean follow-up was of 31.7+/-19 months. Types of lesion were as follows: 33 (48%) stenoses, 23 (33%) insufficiencies, and 13 (19%) double lesions. Procedures were: 64 (93%) valvuloplasties, 3 (4%) biological and 2 (3%) mechanical prosthesis placement. There were 9 (13%) patients with previous systemic embolism and 2 (3%) had left atrial thrombi. RESULTS: Early mortality was 7% and late 1%. 2 patients (3%) were reoperated for mitral placement. At last evaluation, 10 patients (15%), were in AF. The remaining 59 (85%) were either in sinus / atrial rythm (74%) or under pacing (12%). There were no occurrence of early or late, systemic or pulmonary embolism. Permanent anticoagulation was employed in 16 cases, 10 in regular rythm and 6 in AF. The remaining 47 (75%), 2 in AF and 45 in regular rythm, did not receive anticoagulants. CONCLUSIONS: These results are in accordance with others series, where the occurrence of embolism was rare after maze procedure. Permanent systemic anticoagulation seems to be unnecessary in those cases.
Assuntos
Fibrilação Atrial/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Valva Mitral/cirurgia , Complicações Pós-Operatórias/epidemiologia , Tromboembolia/epidemiologia , Adulto , Idoso , Fibrilação Atrial/etiologia , Brasil/epidemiologia , Doença Crônica , Feminino , Doenças das Valvas Cardíacas/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos RetrospectivosRESUMO
OBJECTIVE: To assess the efficacy of surgical isolation of the pulmonary veins for re-establishing sinus rhythm in patients with atrial fibrillation secondary to mitral valve disease. METHODS: Thirty-three (67% were women) patients with permanent atrial fibrillation and indication for surgical correction of the mitral valve underwent surgical isolation of the pulmonary veins. Their mean age was 56.3+/-10 years, preoperative NYHA functional class was 3.2+/-0.6, left atrial size was 5.5+/-0.9 cm, and ejection fraction was 61.3+/-13%. The surgical technique consisted of a circumferential incision surrounding the 4 pulmonary veins, excision of the left atrial appendage, and a perpendicular incision originating in the inferior margin of the circumferential incision isolating the pulmonary veins down to the mitral valve. Early arrhythmias were aggressively treated with cardioversion. RESULTS: The mean follow-up was 23.9+/-17 months, and 3 patients died in the postoperative period. Ten patients required electrical cardioversion in the postoperative period; 87% had sinus rhythm in the last medical visit, and 33% were using amiodarone. CONCLUSION: Isolation of the pulmonary veins associated with mitral valve surgery is an effective and safe technique for maintaining sinus rhythm in patients with permanent atrial fibrillation.
Assuntos
Fibrilação Atrial/cirurgia , Insuficiência da Valva Mitral/cirurgia , Veias Pulmonares/cirurgia , Adulto , Idoso , Fibrilação Atrial/etiologia , Procedimentos Cirúrgicos Cardíacos/mortalidade , Feminino , Seguimentos , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Período Pós-Operatório , Resultado do TratamentoRESUMO
BACKGROUND: Atrioventricular nodal reentrant tachycardia (AVNRT) is probably the most common form of paroxysmal supraventricular tachycardia. Percutaneous catheter ablation is a technique to interrupt cardiac conduction pathways selectively. The anesthetist is challenged to provide a safe anesthetic which takes into account the electrophysiologist's requirements for minimal cardiac conduction interference. Propofol is an ideal drug. However, previous studies have shown that the infusion of propofol has sometimes been associated with bradyarrhythmias or conversion of arrhythmias to sinusal rhythm. The purpose of this report is to verify the interferences of propofol in the electrophysiological properties of the atrioventricular (AV) node conduction system in patients with AVNRT. METHODS: Patients were randomly assigned to receive either a placebo or propofol at sedative doses. An electrophysiological study was performed consisting of measuring the anterograde (AERPFP) and retrograde effective refractory period of the fast (RERPFP) and the anterograde effective refractory period of the slow (AERPSP) AV nodal pathway. Reciprocating tachycardia was induced and the cycle length (CL) and atrial-His (AH), His-ventricular (HV), and ventriculoatrial (VA) intervals were measured. RESULTS: Propofol did not cause alteration (P > 0.05) in the AERPFP or RERPFP and the AERPSP AV nodal pathway. The AH, HV, and VA intervals were not affected. Sustained reciprocating tachycardia could be induced in the all patients. All slow pathways were successfully identified and ablated. CONCLUSION: Propofol has no effect on the electrophysiological properties of the AV node conduction system. It is thus a suitable anesthetic agent for use in patients undergoing ablative procedures.
Assuntos
Nó Atrioventricular/efeitos dos fármacos , Nó Atrioventricular/fisiopatologia , Propofol/administração & dosagem , Taquicardia por Reentrada no Nó Atrioventricular/tratamento farmacológico , Taquicardia por Reentrada no Nó Atrioventricular/fisiopatologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Hipnóticos e Sedativos/administração & dosagem , Masculino , Taquicardia por Reentrada no Nó Atrioventricular/diagnóstico , Taquicardia por Reentrada no Nó Atrioventricular/cirurgia , Resultado do TratamentoRESUMO
OBJETIVO: Avaliar a forma de apresentaçäo, diagnóstico e tratamento das taquiarritmias supraventriculares fetais, através do relato de uma série de casos acompanhados em um centro terciário de cardiologia fetal. MÉTODOS: Säo descritos 25 casos de taquiarritmia supraventricular diagnosticados intra-útero, no período de janeiro/89 a outubro/97, em uma populaçäo compreendendo 3117 gestantes. RESULTADOS: Foram diagnosticados 17 casos taquiarritmia supraventricular e 8 casos de flutter atrial fetal. As idades gestacionais variam de 26 a 40 semanas. Doze fetos apresentavam hidropisia no momento do diagnóstico (6 com taquicardia supraventricular (TSV) e 6 com flutter atrial). Quatro fetos com TSV apresentavam cardiopatias estruturais (dois casos de anomalia de Ebstein e dois com comunicaçäo interventricular). Todos os fetos foram internados na Unidade de Cardiologia Fetal para monitorizaçäo e tratamento. Entre os 17 fetos com TSV, 12 apresentaram reversäo da arritmia após administraçäo de digoxina, mas esta medida näo foi eficaz em nenhum paciente com flutter. Dois pacientes com TSV e seis com necessitaram interrupçäo da gestaçäo para cardioversäo elétrica pós-natal. A mortalidade foi de 3/17 no grupo da TSV (incluindo dois pacientes com anomalia de Ebstein) e de 0/8 no grupo com flutter. CONCLUSÄO: As taquiarritmias supraventriculares fetais säo enventos raros na populaçäo geral. Entretanto, podem provocar insuficiência cardíaca e óbito intrauterino. Como a resposta ao tratamento é satisfatória, tornam-se de extrema importância o diagnóstico precoce e o tratamento adequado.
Assuntos
Humanos , Feminino , Gravidez , Antiarrítmicos/uso terapêutico , Doenças Fetais/diagnóstico , Doenças Fetais/tratamento farmacológico , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/tratamento farmacológico , Adenosina/uso terapêutico , Amiodarona/uso terapêutico , Digoxina/uso terapêutico , Eletrocardiografia , Prontuários Médicos , Sotalol/uso terapêutico , Ultrassonografia Pré-NatalRESUMO
Purpose - To assess the presence and the prevalence of arrhythmias and the variability of the heart rate in the medium-term postoperative period following the maze procedure for chronic atrial fibrillation (AF). Methods - Seventeen patients with a mean age of 51.7+12.9 years, who previously underwent the maze procedure without cryoablation for chronic atrial fibrillation, were evaluated with the 24 hour electrocardiogram (ECG) - Holter monitoring from the 6th month after the operation. Valvular and coronary procedures were concomitantly performed. Results - The mean heart rate during Holter monitoring was 82+8bpm; the maximal heart rate was 126+23 bpm and the minimal heart rate 57+7 bpm. Sinus rhythm was found in 10 (59 per cent) patients and atrial rhythm was found in 7 (41 per cent). Supraventricular extrasystoles had a rate of 2.3+5.5 per cent of the total number of heartbeats and occurred in 16 (94 per cent) patients. Six (35 per cent) patients showed nonsustained atrial tachycardia. Ventricular extrasystoles, with a rate of 0.8+0.5 per cent of the total heart-beast, occurred in 14 (82 per cent) patients. The chronotropic competence was normal in 9 (53 per cent) patients and attenuated in 8 (47 per cent). The atrioventricular conduction (AV) was unchanged in 13 (76 per cent) patients and there were 4 (24 per cent) cases of first degree atrioventricular block (AVB). Conclusion - After maze procedure, the values for the mean heart rrate, AV conduction and chronotropic competence approach the normal range, although some cases show attenuation of the chronotropic responce, first degree AV block or benign arrhythmias.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/epidemiologia , Fibrilação Atrial/cirurgia , Frequência Cardíaca , Doença Crônica , Período Pós-Operatório , PrevalênciaRESUMO
This is the report of a case of fetal tachyarrhythmia with 1:1 atrioventricular conduction detected by pre-natal echocardiography in a fetus at 25-weeks gestation. Adenosine infusion via cordocentesis was performed as a diagnostic test to differentiate between atrioventricular nodal reentrant supraventricular tachyarrhythmia and atrial flutter. After infusion, transient 2:1 atrioventricular dissociation was obtained and the diagnosis of atrial flutter was made. Transplacental therapy with digoxin and amiodarone was then successfully used.
Assuntos
Humanos , Feminino , Gravidez , Adulto , Adenosina , Antiarrítmicos , Complicações Cardiovasculares na Gravidez , Taquicardia Supraventricular , Ultrassonografia Pré-Natal/métodos , Adenosina/administração & dosagem , Antiarrítmicos/administração & dosagem , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Taquicardia Supraventricular/tratamento farmacológico , Veias UmbilicaisRESUMO
OBJETIVO: Analisar a eficácia do isolamento cirúrgico das veias pulmonares para restabelecer ritmo sinusal em pacientes com fibrilação atrial secundária à doença mitral. MÉTODOS: 33 pacientes com indicação de correção cirúrgica da valva mitral e com fibrilação atrial permanente, foram submetidos ao isolamento cirúrgico das veias pulmonares, sendo 67 por cento mulheres. Média de idade de 56,3±10 anos, classe funcional NYHA pré-operatória de 3,2±0,6, tamanho de átrio esquerdo de 5,5± 0,9 cm, fração de ejeção de 61,3±13 por cento. A técnica cirúrgica consistiu de incisão circunferencial ao redor das 4 veias pulmonares, excisão do apêndice atrial esquerdo e de incisão perpendicular desde a borda inferior da incisão, isolando as veias pulmonares, até o ânulo da valva mitral. Arritmias precoces foram tratadas, agressivamente, com cardioversão. RESULTADOS: O seguimento médio foi de 23,9±17 meses e ocorreram 3 óbitos no pós-operatório. Dez pacientes necessitaram de cardioversão elétrica no pós-operatório; 87 por cento apresentavam ritmo sinusal na última consulta e 33 por cento estavam em uso de amiodarona. CONCLUSAO: Isolamento das veias pulmonares associado à cirurgia da valva mitral é uma técnica efetiva e segura na manutenção de ritmo sinusal em pacientes com fribilação atrial permanente.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Fibrilação Atrial/cirurgia , Procedimentos Cirúrgicos Cardíacos , Insuficiência da Valva Mitral/cirurgia , Veias Pulmonares/cirurgia , Fibrilação Atrial/etiologia , Procedimentos Cirúrgicos Cardíacos/mortalidade , Seguimentos , Frequência Cardíaca , Insuficiência da Valva Mitral/complicações , Período Pós-Operatório , Resultado do TratamentoRESUMO
OBJECTIVE: To assess the occurrence of late thromboembolism after surgical repair of chronic atrial fibrillation (AF) simultaneously with repair of mitral valve using the Cox-Maze procedure. METHODS: 69 patients underwent Cox 3 procedure, with no cryoablation simultaneously with mitral valvuloplasty or prosthesis. Mean age was 49.9±13.2 years. Mean follow-up was of 31.7±19 months. Types of lesion were as follows: 33 (48 percent) stenoses, 23 (33 percent) insufficiencies, and 13 (19 percent) double lesions. Procedures were: 64 (93 percent) valvuloplasties, 3 (4 percent) biological and 2 (3 percent) mechanical prosthesis placement. There were 9 (13 percent) patients with previous systemic embolism and 2 (3 percent) had left atrial thrombi. RESULTS: Early mortality was 7 percent and late 1 percent. 2 patients (3 percent) were reoperated for mitral placement. At last evaluation, 10 patients (15 percent), were in AF. The remaining 59 (85 percent) were either in sinus / atrial rythm (74 percent) or under pacing (12 percent). There were no occurrence of early or late, systemic or pulmonary embolism. Permanent anticoagulation was employed in 16 cases, 10 in regular rythm and 6 in AF. The remaining 47 (75 percent), 2 in AF and 45 in regular rythm, did not receive anticoagulants. CONCLUSIONS: These results are in accordance with others series, where the occurrence of embolism was rare after maze procedure. Permanent systemic anticoagulation seems to be unnecessary in those cases
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Fibrilação Atrial , Doenças das Valvas Cardíacas , Valva Mitral , Complicações Pós-Operatórias , Tromboembolia , Fibrilação Atrial , Brasil , Doença Crônica , Doenças das Valvas Cardíacas , Prevalência , Estudos RetrospectivosRESUMO
Objective - Report clinical experience in surgical treatment of atrial fibrillation (AF) by Cox-maze procedure. Methods - 61 patients underwent surgical treatment for AF. Two had primary AF and 59 AF secondary to heart disease (2 atrial septal defects, 57 mitral). Ages ranged from 20 to 74 years (mean = 49). There were 44 females (72 per cent). The surgical technique employed was Cox 3 without cryoablation. The patients were follow-up in specific at patient clinics and underwent periodical ECG, exercise texts, echocardiogram and Holter monitoring. Results - In-hospital mortality was 4.9 per cent and late mortality 1.6 per cent. A temporary pacemaker was used in 28 (46 per cent) and a definitive in 7 patients (11.4 per cent). On hospital discharge, AF remained in 17 per cent; 63.9 per cent had sinus rhythm, 6.9 per cent atrial rhythm, and 10.3 per cent had pacemaker rhythm. In the last evaluattion, AF was present in 19.5 per cent; (70.5 per cent sinus rhythm, 4 per cent atrial rhythm, 2 per cent atrial tachycardia, and 4 per cent pacemaker rhythm). There was no report of thromboembolic episodes. Chronotropic response was considered adequate in 19 per cent, intermediate in 29 per cent, and inadequate in 42 per cent. In Holter monitoring, the mean heart rate was 82+8 bpm, with a minimum of 57+7 bpm and maximum of 126+23 bpm, with supraventricular extrasystoles in 2.3+5.5 per cent of the total hearbeats and ventricular extrasystoles in 0.8+0.5 per cent. In the echocardiogram, the A wave was present in the left atrium in 87.5 per cent. Conclusion - Maze procedure is effective and has acceptable surgical risk. Atrial or sinus rhythms remain stable with a small but remarkable frequency of atrial and ventricular arrhythmias. Left atrial contraction is present, although attenuated, as well as the chronotropic response to exercise.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Fibrilação Atrial/cirurgia , Procedimentos Cirúrgicos Cardíacos/métodos , Doença Crônica , Frequência Cardíaca , Resultado do TratamentoRESUMO
INTRODUÇÃO: Fibrilação atrial tem sido tratada pelo procedimento do Labirinto (Cox) e suas modificações. Há, no entanto, evidências de que o isolamento dos óstios das veias pulmonares ou exclusão do átrio esquerdo poderia ser eficaz para este fim. CASUÍSTICA E MÉTODOS: Avaliamos os resultados iniciais da técnica simplificada de isolamento cirúrgico dos óstios das veias pulmonares para tratar fibrilação atrial crônica em pacientes operados por lesão valvar mitral. Foram tratados 7 pacientes por esta técnica (grupo IVP) e comparados com série prévia de 57 casos submetidos a cirurgia do Labirinto (Cox 3). RESULTADOS: A idade média foi de 49 + ou - 8 anos vs 49 + ou -11 anos, (IVP vs. Cox3), sendo 71 por cento e 72 por cento (IVP vs. Cox 3) do sexo feminino. Dimensões do átrio esquerdo 5,5 + ou -0,7 cm vs. 6,0 + ou -1,1 cm (IVP vs. Cox 3). Fração de ejeção ventricular 63 + ou -10 por cento vs. 64 + ou -6 por cento (IVP vs. Cox 3). Tempo CEC 91 + ou -33 min vs. 104 + ou - 29 min (IVP vs. Cox 3). Tempo de isquemia 71 + ou - 23 min vs. 83 + ou - 26 min (IVP vs. Cox 3). Ritmo pós-operátório sinusal/atrial n(por cento): 6(86) vs. 46(80) (IVP vs. Cox 3). Ritmo marcapasso n(por cento):1 (14) vs. 4 (7) (IVP vs. Cox 3). Fibrilação atrial n( por cento): 0 vs. 7 (13) (IVP vs. Cox 3). CONCLUSÕES: Resultados iniciais mostram reversão a ritmo sinusal na maioria dos casos em ambos procedimentos e manutenção do ritmo a longo prazo. Foi iniciado estudo prospectivo randomizado para avaliar o IVP comparativamente ao procedimento Cox 3.
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Cardíacos , Fibrilação Atrial/cirurgia , Fibrilação Atrial/etiologia , Valva Mitral/patologia , Valva Mitral/cirurgia , Doença Crônica , Veias Pulmonares/cirurgiaRESUMO
A estimulação bicameral utilizando um eletrodo flutuante único (modo VDD) pode ser indicada em pacientes com bloqueio atrioventricular (BAV) total e função sinusal normal, fundamentada na simplicidade oferecida pelo uso de apenas um eletrodo para obter o sincronismo AV. Contudo, subsistem dúvidas relativas à estabilidade tardia da função atrial e à efetividade do eletrodo em manter a leitura efetiva da onda P. Este estudo prospectivo visou a avaliação tardia da onda P sentida pelo eletrodo AV único em 40 pacientes que haviam implantado marcapasso VDD. O eletrodo fractal flutuante único SL60 Biotronik foi implantado por via transvenosa, teve a posição aferida por escopia. As medidas eletrofisiológicas revelaram onda P média de 2,4 Ý 1,0 mV, QRS médio de 11,0 Ý 3,8 mV e limiar de estimulação ventricular médio de 0,4 Ý 0,2 V. A programação padrão do gerador Dromos SL Biotronik foi mantida, com sensibilidade atrial de 0,2 mV. Após a alta hospitalar, os pacientes foram acompanhados periodicamente pelo clínico ou em ambulatório. A avaliação específica da amplitude mínima da onda P com o paciente na posição deitada ou sentada foi realizada em um período pós?implante que variou de 3 a 36 meses (média de 24 meses), com auxílio da telemetria do gerador. Durante o acompanhamento registrou-se perda do sinal e do comando atrial em 5 (12,5por cento) doentes. A reposição do eletrodo foi efetuada em 2 (5por cento ), a reprogramação da sensibilidade atrial em 2 (2,5por cento) e a reprogramação em modo VVI em 1 (2,5por cento) paciente. Quando da última revisão, 39 (97,5por cento) pacientes mostraram adequado sincronismo atrioventricular mediado pelo marcapasso. A avaliação tardia indicou média da onda P mínima de 1,6 Ý 1,4 mV em posição sentada e de 1,6 Ý 1,5 mV para os pacientes em pé, valores inferiores ao registrado no implante, mas superiores ao limiar de sensibilidade do marcapasso. Concluímos que o sistema de estimulação VDD com eletrodo fractal flutuante único é uma alternativa satisfatória para os pacientes com distúrbio de condução AV e atividade elétrica atrial normal. Seu emprego em pacientes com miocardiopatia severa ou que utilizem drogras antiarritmicas ou cronotrópico-negativas deve ser individualmente avaliado
Assuntos
Humanos , Estimulação Cardíaca Artificial , Marca-Passo Artificial , Bloqueio Cardíaco/cirurgia , EletrodosRESUMO
Fibrilação atrial é uma arritmia cardíaca sustentada com expressiva prevalência na população. A ocorrência de fibrilação atrial aumenta de três a cinco vezes o risco de acidentes vasculares cerebrais isquêmicos e este risco é ainda maior quando existe concomitância de valvulopatia. O presente artigo faz uma atualização dos principais aspectos clínicos, epidemiológicos, fisiopatológicos e terapêuticos da doença