RESUMO
BACKGROUND/PURPOSE: Andersen-Tawil syndrome type 1 is a rare autosomal dominant disease caused by a KCNJ2 gene mutation and clinically characterized by dysmorphic features, periodic muscular paralysis, and frequent ventricular arrhythmias (VAs). Although polymorphic and bidirectional ventricular tachycardias are prevalent, PVCs are the most frequent VAs. In addition, a "dominant" morphology with RBBB pattern associated with either superior or inferior axis is seen in most of the patients. Due to the limited efficacy of most antiarrhythmic drugs, catheter ablation (CA) is an alternative in patients with monomorphic VAs. Based on our experience, we aimed to review the arrhythmogenic mechanisms and substrates for VAs, and we analyzed the potential reasons for CA failure in this group of patients. METHODS: Case report and focused literature review. RESULTS: Catheter ablation has been reported to be unsuccessful in all of the few cases published so far. Most of the information suggests that VAs are mainly originated from the left ventricle and probably in the Purkinje network. Although identifying well-established and accepted mapping criteria for successful ablation of a monomorphic ventricular arrhythmia, papillary muscles seem not to be the right target. CONCLUSIONS: More research is needed to understand better the precise mechanism and site of origin of VAs in Andersen-Tawil syndrome patients with this particular "dominant" monomorphic ventricular pattern to establish the potential role of CA.
Assuntos
Síndrome de Andersen , Ablação por Cateter , Taquicardia Ventricular , Complexos Ventriculares Prematuros , Humanos , Síndrome de Andersen/genética , Síndrome de Andersen/cirurgia , Síndrome de Andersen/complicações , Ventrículos do Coração/cirurgia , Complexos Ventriculares Prematuros/cirurgia , Ablação por Cateter/efeitos adversosRESUMO
AIM: To evaluate the influence of high-intensity interval training (HIIT) on cardiac structural and functional characteristics and myocardial mitogen-activated protein kinase (MAPK) signaling in hypertensive rats. METHODS: Male rats (12 months old) were divided into three groups: Wistar Kyoto rats (WKY, n = 8); sedentary spontaneously hypertensive rats (SED-SHR, n = 10), and trained spontaneously hypertensive rats (HIIT-SHR, n = 10). Systolic blood pressure (SBP), functional capacity, echocardiography, isolated papillary muscle, and gene expression of MAPK gene-encoding proteins associated with Elk1, cJun, ATF2, MEF2 were analyzed. KEY FINDINGS: HIIT decreased SBP and increased functional capacity, left ventricular diastolic diameter, posterior wall thickness-left ventricle, relative wall thickness-left ventricle, and resting tension of the papillary muscle. In hypertensive rats, we observed a decrease in the gene-encoding ATF2 protein; this decrease was reversed by HIIT. SIGNIFICANCE: The influence of HIIT in the SHR model in the compensated hypertension phase generated an increase in cardiac hypertrophy, attenuated myocardial diastolic dysfunction, lowered blood pressure, improved functional capacity, and reversed the alteration in gene-encoding ATF2 protein.
Assuntos
Treinamento Intervalado de Alta Intensidade , Hipertensão , Animais , Pressão Sanguínea/fisiologia , Hipertensão/metabolismo , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Miocárdio/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Remodelação Ventricular/fisiologiaRESUMO
Abstract Background: Hyperthyroidism (Hy) is an endocrine disorder, in which the thyroid hormones markedly alter the cardiac function. Increased myocardial contractility and cardiac output, improvement in diastolic relaxation, changes in electrical activity, increments in ventricular mass, and arrhythmias have been reported. However, the influences of thyroid hormones upon molecular mechanisms of cardiac functions have not yet been fully understood. Objectives: To evaluate changes in cardiac contractile parameters and the Na+/Ca2+ exchanger (NCX) function in induced hyperthyroid rats. Methods: Hy was induced by intraperitoneal injections of T3 (15 μg/100 g) for 10 days. Contractile parameters and NCX function were evaluated in the isolated papillary muscle. Data normality was confirmed by the Shapiro-Wilk test. The comparison between groups was performed through an unpaired Student's t-test. Results are expressed as mean ± SD. The accepted significance level was p < 0.05. Results: Our data revealed, in the Hy group, an increase of 30.98% in the maximum speed of diastolic relaxation (-284.64 ± 70.70 vs. -217.31 ± 40.30 mN/mm2/sec (p = 0.027)) and a boost of 149% in the NCX function in late phase of relaxation (20.17 ± 7.90 vs. 50.22 ± 11.94 minutes (p = 0.002)), with no changes in the maximum twitch force (p = 0.605) or maximum speed of systolic contraction (p = 0.208) when compared to the control. Conclusion: The improvement in relaxation parameters is hypothetically attributed to an increase in Sarco-Endoplasmic Reticulum Ca2+ATPase isoform 2 (SERCA2) expression and an increased calcium flow through L-type channels that boosted the NCX function.
Assuntos
Animais , Masculino , Ratos , Músculos Papilares/fisiologia , Trocador de Sódio e Cálcio/fisiologia , Hipertireoidismo/complicações , Hormônios Tireóideos , Ratos WistarRESUMO
Introducción: La válvula mitral en paracaídas-like es una anomalía congénita caracterizada por una disposición asimétrica de los músculos papilares, siendo las pruebas de imagen cardiaca son el procedimiento de elección tanto para el diagnóstico anatómico como para realizar la valoración funcional de este tipo de anomalía estructural. Caso Clínico: Paciente con cuadro de descompensación hemodinámica en el cual se diagnóstica de manera incidental de una valvulopatía mitral en forma de paracaídas-like. Los hallazgos de imagen por ecocardiografía transtorácica y resonancia magnética ponen de manifiesto la presencia de 2 músculos papilares, ambos con inserción en segmento lateral apical confirmando una válvula mitral asimétrica con similitud a su morfología en paracaídas. Discusión: La válvula mitral en paracaídas es una anomalía congénita poco común constituyente en la presencia de dos músculos papilares siendo uno de ellos más elongado y adherido al velo mitral de forma contigua, mostrándose en algunos casos pequeñas cuerdas tendinosas asociadas. Puede presentar una evolución benigna siendo un hallazgo casual o asociarse a repercusión hemodinámica valvular como el caso presentado. Conclusión: La válvula mitral en paracaídas-like es una anomalía congénita caracterizada por una disposición asimétrica de los músculos papilares, siendo su evolución muy variable, pudiendo pasar desapercibida o afectando de forma significativa a la mecánica valvular.
Introducción: La válvula mitral en paracaídas-like es una anomalía congénita caracterizada por una disposición asimétrica de los músculos papilares, siendo las pruebas de imagen cardiaca son el procedimiento de elección tanto para el diagnóstico anatómico como para realizar la valoración funcional de este tipo de anomalía estructural. Caso Clínico: Paciente con cuadro de descompensación hemodinámica en el cual se diagnóstica de manera incidental de una valvulopatía mitral en forma de paracaídas-like. Los hallazgos de imagen por ecocardiografía transtorácica y resonancia magnética ponen de manifiesto la presencia de 2 músculos papilares, ambos con inserción en segmento lateral apical confirmando una válvula mitral asimétrica con similitud a su morfología en paracaídas. Discusión: La válvula mitral en paracaídas es una anomalía congénita poco común constituyente en la presencia de dos músculos papilares siendo uno de ellos más elongado y adherido al velo mitral de forma contigua, mostrándose en algunos casos pequeñas cuerdas tendinosas asociadas. Puede presentar una evolución benigna siendo un hallazgo casual o asociarse a repercusión hemodinámica valvular como el caso presentado. Conclusión: La válvula mitral en paracaídas-like es una anomalía congénita caracterizada por una disposición asimétrica de los músculos papilares, siendo su evolución muy variable, pudiendo pasar desapercibida o afectando de forma significativa a la mecánica valvular.
Assuntos
Insuficiência da Valva Mitral , Músculos Papilares , Humanos , Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/diagnóstico por imagem , Músculos Papilares/diagnóstico por imagemRESUMO
Abstract We compared the mortality rates of two surgical techniques for correction of atrioventricular disjunction in 10 out of 720 patients who underwent mitral valve replacement from 2005 to 2012. In group I, the mitral annulus was fixed with bovine pericardial strips; in group II, a 'patch' of bovine pericardium was sutured and extended from the base of the lateral and medial papillary muscles, covered the posterior wall of the left ventricle, went through the posterior mitral annulus, and ended in the posterior wall of the left atrium adjacent to the mitral ring. The group II technique showed a lower mortality.
Assuntos
Humanos , Animais , Nó Atrioventricular/cirurgia , Valva Mitral/cirurgia , Insuficiência da Valva Mitral , Músculos Papilares/cirurgia , Pericárdio/transplante , Valva Tricúspide , BovinosRESUMO
We compared the mortality rates of two surgical techniques for correction of atrioventricular disjunction in 10 out of 720 patients who underwent mitral valve replacement from 2005 to 2012. In group I, the mitral annulus was fixed with bovine pericardial strips; in group II, a 'patch' of bovine pericardium was sutured and extended from the base of the lateral and medial papillary muscles, covered the posterior wall of the left ventricle, went through the posterior mitral annulus, and ended in the posterior wall of the left atrium adjacent to the mitral ring. The group II technique showed a lower mortality.
Assuntos
Nó Atrioventricular/cirurgia , Insuficiência da Valva Mitral , Valva Mitral , Animais , Bovinos , Humanos , Valva Mitral/cirurgia , Músculos Papilares/cirurgia , Pericárdio/transplante , Valva TricúspideRESUMO
PURPOSE: Transthoracic echocardiography (TTE) is currently the election method for initial screening of left ventricular papillary muscles (PM). However, diagnosis of borderline PM hypertrophy with TTE is not always feasible due to cumbersome interpretation of different PM diameters and the absence of precise normal ranges in the literature. The objective of this study was to obtain TTE normal cutoff values and to describe convenient indexes of PM dimensions. METHODS: Healthy volunteers with normal electrocardiogram were included for TTE assessment. Vertical (Vd) and horizontal (Hd) PM diameters were measured to obtain maximum diameter (Md) and areas of the anterolateral PM (APM) and posteromedial PM (PPM) to obtain PM total area (PMTA). RESULTS: A total of 82 patients were screened, and 6 (7.3%) with bifid PM were excluded from analysis. APM and PPM had similar Vd (APM: 8.3 ± 1.2, PPM: 7.9 ± 1.1 mm2 , P = NS) and Hd (APM: 8.2 ± 1.3, PPM: 8.3 ± 1.2 mm2 , P = NS). Finally, Md (9 ± 1.2 mm; P95 = 11 mm) and PMTA (106.5 ± 24.2 mm2 ; P95 = 150.8 mm2 ) were obtained. Correlation between PMTA and Md was positive (P < .001), and out-of-range values for Md and PMTA were similar (2.6% vs 5.3%); there was excellent agreement between both indexes (K = 0.82). CONCLUSIONS: Maximum diameter and PMTA are convenient indexes to describe PM dimensions. However, given the high equivalence between both indexes, we propose the use of Md due to its simplicity and ease of calculation. Our findings suggest that patients with any PM diameter ≥12 mm should be considered abnormal.
Assuntos
Ecocardiografia , Músculos Papilares , Ventrículos do Coração/diagnóstico por imagem , Humanos , Hipertrofia , Músculos Papilares/diagnóstico por imagemRESUMO
INTRODUCTION: The number of cases for which the Batista procedure is indicated is small, but some patients with appropriate indication can achieve good therapeutic results. OBJECTIVE: To avoid incorrect left ventricular incision and obtain good surgical results in patients with dilated cardiomyopathy suitable for partial left ventriculectomy, we employed intraoperative direct echocardiography to determine the exact extent and position of the myocardial incision, even for surgeons who are not very experienced with the Batista procedure. METHODS: A 72-year-old man with dilated cardiomyopathy underwent the Batista procedure with the aid of epicardial echocardiography to confirm the location of both the papillary muscles and the diseased myocardium. RESULTS: We were able to accurately perform left ventricular incision and remove the diseased lateral ventricular wall. Two years later, the patient had no symptoms of heart failure, and his brain natriuretic peptide (BNP) level decreased from 1155 to 49.3 pg/mL. CONCLUSIONS: We believe that the use of intraoperative echocardiography may have the potential to make the Batista procedure less technically demanding and more reproducible for surgeons with little experience in the procedure.
Assuntos
Ecocardiografia , Idoso , Procedimentos Cirúrgicos Cardíacos , Cardiomiopatia Dilatada , Insuficiência Cardíaca , Ventrículos do Coração , Humanos , MasculinoRESUMO
Abstract Introduction: The number of cases for which the Batista procedure is indicated is small, but some patients with appropriate indication can achieve good therapeutic results. Objective: To avoid incorrect left ventricular incision and obtain good surgical results in patients with dilated cardiomyopathy suitable for partial left ventriculectomy, we employed intraoperative direct echocardiography to determine the exact extent and position of the myocardial incision, even for surgeons who are not very experienced with the Batista procedure. Methods: A 72-year-old man with dilated cardiomyopathy underwent the Batista procedure with the aid of epicardial echocardiography to confirm the location of both the papillary muscles and the diseased myocardium. Results: We were able to accurately perform left ventricular incision and remove the diseased lateral ventricular wall. Two years later, the patient had no symptoms of heart failure, and his brain natriuretic peptide (BNP) level decreased from 1155 to 49.3 pg/mL. Conclusions: We believe that the use of intraoperative echocardiography may have the potential to make the Batista procedure less technically demanding and more reproducible for surgeons with little experience in the procedure.
Assuntos
Humanos , Masculino , Idoso , Ecocardiografia , Cardiomiopatia Dilatada , Insuficiência Cardíaca , Procedimentos Cirúrgicos Cardíacos , Ventrículos do CoraçãoRESUMO
BACKGROUND: Papillary muscles (PM) ventricular arrhythmias (VAs) exhibit QRS variability, attributed to anisotropy. ECG inconsistencies such as late precordial transition (TZ) and discordant QRS axis may not be solely explained by anisotropic conduction. We sought to determine the presence of anatomic connections of the PM and correlate them with ECG inconsistencies and ablation results. METHODS: Patients with prior PM VAs catheter ablation (N=33/66 PMs) were prospectively evaluated with cardiac resonance for the presence of muscular connection (PMCs) away from the PM base. Specific ECG characteristics including early (consistent TZ) and late (inconsistent-ITZ) TZ or inconsistent (IQA) or consistent QA QRS axis were correlated with PMCs. RESULTS: Thirty-five PMs exhibited clinical VAs (N=29 posteromedial PM and N=6 anterolateral PM). PM VAs with ITZ and IQA were observed in 11 and 9 PMs, respectively. In total, 41 PMs (62%) exhibited 90 PMCs. Arrhythmogenic PMs (N=35) exhibited higher number of PMCs (72 versus 18; P=0.01). Patients with ITZ and IQA exhibited 100% prevalence of PMCs. Those with consistent TZ and consistent QA showed 40% and 26% prevalence of PMCs, respectively. ITZ and IQA predicted the presence of PMCs with 59% of 28% sensitivity; and 100% of 100% specificity, respectively. Type-specific PMCs were more prevalent in patients with ECG inconsistencies. Those PMs are exhibiting clinical recurrence after ablation presented higher prevalence of PMCs (91% versus 60%; P=0.04). CONCLUSIONS: PMCs are highly prevalent in patients with PM VAs. A direct correlation exists between PM VAs ECG inconsistencies and type-specific PMCs. Patients with ITZ or IQA exhibited PMC 100% prevalence. Recurrence was higher among patients with PMCs.
Assuntos
Arritmias Cardíacas/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética , Miocárdio/patologia , Músculos Papilares/diagnóstico por imagem , Potenciais de Ação , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/cirurgia , Ablação por Cateter , Eletrocardiografia , Frequência Cardíaca , Ventrículos do Coração/fisiopatologia , Ventrículos do Coração/cirurgia , Humanos , Músculos Papilares/fisiopatologia , Músculos Papilares/cirurgia , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Recidiva , Fatores de Tempo , Resultado do TratamentoRESUMO
Abstract This paper presents a case study of a 30-year-old male patient with dyspnea on exertion had echocardiographic diagnosis of aortic subvalvar stenosis. Discrete mitral regurgitation and aortic valve dysplasia with mild to moderate insufficiency and hypertrophic cardiomyopathy were also noted. During surgery, a rare condition was identified: presence of papillary muscle anomaly associated with the subaortic membrane as a cause of obstruction of the left ventricular outflow tract. With the resection of these structures and a mitral valve annuloplasty, the patient evolved with a significant improvement of clinical condition and heart failure, with no residual mitral insufficiency.
Assuntos
Humanos , Masculino , Adulto , Músculos Papilares/anormalidades , Obstrução do Fluxo Ventricular Externo/cirurgia , Estenose Subaórtica Fixa/complicações , Cardiopatias Congênitas/complicações , Músculos Papilares/cirurgia , Obstrução do Fluxo Ventricular Externo/etiologia , Ecocardiografia , Estenose Subaórtica Fixa/cirurgia , Estenose Subaórtica Fixa/diagnóstico por imagem , Anuloplastia da Valva Mitral , Cardiopatias Congênitas/cirurgia , Cardiopatias Congênitas/diagnóstico por imagemRESUMO
Copper is an essential metal for homeostasis and the functioning of living organisms. We investigated the effects of a high copper concentration on the myocardial mechanics, investigating the reactive oxygen species (ROS) mediated effects. The developed force of papillary muscles was reduced after acute exposure to a high copper concentration and was prevented by co-incubation with tempol, DMSO and catalase. The reuptake of calcium by the sarcoplasmic reticulum was reduced by copper and restored by tempol. The contractile response to Ca2+ was reduced and reversed by antioxidants. The response to the ß-adrenergic agonist decreased after exposure to copper and was restored by tempol and catalase. In addition, the in situ detection showed increased O2·- and OH·. Contractions dependent on the sarcolemmal Ca2+ influx were impaired by copper and restored by antioxidants. Myosin-ATPase activity decreased significantly after copper exposure. In conclusion, a high copper concentration can acutely impair myocardial excitation-contraction coupling, reduce the capacity to generate force, reduce the Ca2+ inflow and its reuptake, and reduce myosin-ATPase activity, and these effects are mediated by the local production of O2·-, OH· and H2O2. These toxicity effects of copper overload suggest that copper is a risk factor for cardiovascular disease.
Assuntos
Cobre/toxicidade , Músculos Papilares/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Cálcio/metabolismo , Masculino , Contração Miocárdica/efeitos dos fármacos , Miosinas/metabolismo , Músculos Papilares/metabolismo , Músculos Papilares/fisiologia , Ratos Wistar , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismoRESUMO
Abstract Fundamento: The role of papillary muscle function in severe mitral regurgitation with preserved and reduced left ventricular ejection fraction and the method of choice to evaluate PM have still been the subjects of controversy. Objectives: To evaluate and compare papillary muscle function in and between patients with severe degenerative and functional mitral regurgitation by using the free strain method. Methods: 64 patients with severe mitral regurgitation - 39 patients with degenerative mitral regurgitation (DMR group) and 25 patients with severe functional mitral regurgitation (FMR group) - and 30 control subjects (control group) were included in the study. Papillary muscle function was evaluated through the free strain method from apical four chamber images of the anterolateral papillary muscle (APM) and from apical three chamber images of the posteromedial papillary muscle (PPM). Global left ventricular longitudinal and circumferential strains were evaluated by applying 2D speckle tracking imaging. Results: Global left ventricular longitudinal strain (DMR group, -17 [-14.2/-20]; FMR group, -9 [-7/-10.7]; control group, -20 [-18/-21] p < 0.001), global left ventricular circumferential strain (DMR group, -20 [-14.5/-22.7]; FMR group, -10 [-7/-12]; control group, -23 [-21/-27.5] p < 0.001) and papillary musle strains (PPMS; DMR group, -30.5 [-24/-46.7]; FMR group, -18 [-12/-30]; control group; -43 [-34.5/-39.5] p < 0.001; APMS; DMR group, (-35 [-23.5/-43]; FMR group, -20 [-13.5/-26]; control group, -40 [-32.5/-48] p < 0.001) were significantly different among all groups. APMS and PPMS were highly correlated with LVEF (p < 0.001, p < 0.001; respectively), GLS (p < 0.001, p < 0.001; respectively) and GCS (p < 0.001, p < 0.00; respectively) of LV among all groups. No correlation was found between papillary muscle strains and effective orifice area (EOA) in both groups of severe mitral regurgitation. Conclusions: Measuring papillary muscle longitudinal strain by the free strain method is practical and applicable. Papillary muscle dysfunction plays a small role in severe MR due to degenerative or functional causes and papillary muscle functions in general seems to follow left ventricular function. PPM is the most affected PM in severe mitral regurgitation in both groups of DMR and FMR.
Resumo Fundamento: O papel da função do músculo papilar na regurgitação mitral grave com fração de ejeção do ventrículo esquerdo preservada e reduzida e o método de escolha para avaliar PM ainda são objetos de controvérsia. Objetivos: Avaliar e comparar a função dos músculos papilares entre pacientes com insuficiência mitral funcional e degenerativa pelo método free strain. Métodos: 64 pacientes com insuficiência mitral grave - 39 pacientes com insuficiência mitral degenerativa grave (grupo IMD) e 25 com insuficiência mitral funcional grave (grupo IMF) - e 30 indivíduos controle (grupo controle) foram incluídos no estudo. A função dos músculos papilares foi avaliada pelo método free strain a partir de imagens apicais quatro-câmaras do músculo papilar anterolateral (MPA) e imagens apicais três-câmaras do músculo papilar posteromedial (MPP). Strains circunferenciais e longitudinais globais do ventrículo esquerdo foram avaliados por meio de imagens bidimensionais a partir do rastreamento de conjunto de pontos de cinza (speckle tracking). Resultados: O strain longitudinal global do ventrículo esquerdo (grupo IMD, -17 [-14,2/-20]; grupo IMF, -9 [-7/-10,7]; grupo controle, -20 [-18/-21] p < 0,001); strain circunferencial global do ventrículo esquerdo (grupo IMD, -20 [-14,5/-22,7]; grupo IMF, -10 [-7/-12]; grupo controle, -23 [-21/-27,5] p < 0,001) e strains de músculos papilares (MPP; grupo IMD, -30,5 [-24/-46,7]; grupo IMF, -18 [-12/-30]; grupo controle; -43 [-34,5/-39,5] p < 0,001; MPA; grupo IMD, (-35 [-23,5/-43]; grupo IMF, -20 [-13,5/-26]; grupo controle, -40 [-32,5/-48] p < 0,001) mostraram-se significativamente diferentes nos grupos. MPA e MPP mostraram-se altamente correlacionados com a FEVE (p < 0,001, p < 0,00; respectivamente), SLG (p < 0,001, p < 0,001; respectivamente) e SCG (p < 0,001, p < 0,001; respectivamente) do VE entre todos os grupos. Não foi encontrada correlação entre os strains de músculos papilares e área eficaz do orifício (AEO) nos grupos de insuficiência mitral grave. Conclusões: A medição do strain longitudinal de músculos papilares pelo método free strain é prática e aplicável. A disfunção dos músculos papilares tem um papel pequeno em IM grave devido a causas degenerativas e funcionais, e a função dos músculos papilares, em general, parece seguir a função ventricular esquerda. O MPP é o MP mais afetado na insuficiência mitral em ambos os grupos, IMD e IMF.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Músculos Papilares/fisiopatologia , Insuficiência da Valva Mitral/fisiopatologia , Músculos Papilares/diagnóstico por imagem , Volume Sistólico/fisiologia , Ecocardiografia/instrumentação , Ecocardiografia/métodos , Estudos Prospectivos , Função Ventricular Esquerda/fisiologia , Insuficiência da Valva Mitral/diagnóstico por imagemRESUMO
BACKGROUND: Catheter radiofrequency ablation of ventricular arrhythmias (VAs) arising from the left ventricle's papillary muscles has been associated with inconsistent results. The use of cryoenergy versus radiofrequency has not been compared yet. This study compares outcomes and complications of catheter ablation of VA from the papillary muscles of the left ventricle with either cryoenergy or radiofrequency. METHODS AND RESULTS: Twenty-one patients (40±12 years old; 47% males; median ejection fraction 59±7.3%) with drug refractory premature ventricular contractions or ventricular tachycardia underwent catheter cryoablation or radiofrequency ablation. VAs were localized using 3-dimensional mapping, multidetector computed tomography, and intracardiac echocardiography, with arrhythmia foci being mapped at either the anterolateral papillary muscle or posteromedial papillary muscles of the left ventricle. Focal ablation was performed using an 8-mm cryoablation catheter or a 4-mm open-irrigated radiofrequency catheter, via transmitral approach. Acute success rate was 100% for cryoenergy (n=12) and 78% for radiofrequency (n=9; P=0.08). Catheter stability was achieved in all patients (100%) treated with cryoenergy, and only in 2 (25%) patients treated with radiofrequency (P=0.001). Incidence of multiple VA morphologies was observed in 7 patients treated with radiofrequency (77.7%), whereas none was observed in those treated with cryoenergy (P=0.001). VA recurrence at 6 months follow-up was 0% for cryoablation and 44% for radiofrequency (P=0.03). CONCLUSIONS: Cryoablation was associated with higher success rates and lower recurrence rates than radiofrequency catheter ablation, better catheter stability, and lesser incidence of polymorphic arrhythmias.
Assuntos
Ablação por Cateter/métodos , Criocirurgia/métodos , Ecocardiografia/métodos , Endossonografia/métodos , Sistema de Condução Cardíaco/cirurgia , Cirurgia Assistida por Computador/métodos , Taquicardia Ventricular/cirurgia , Adulto , Eletrocardiografia , Feminino , Seguimentos , Sistema de Condução Cardíaco/diagnóstico por imagem , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Músculos Papilares/inervação , Músculos Papilares/cirurgia , Estudos Retrospectivos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologiaRESUMO
PURPOSE: To study racemic bupivacaine, non-racemic bupivacaine and ropivacaine on myocardial contractility. METHODS: Isolated Wistar papillary muscles were submitted to 50 and 100 mM racemic bupivacaine (B50 and B100), non-racemic bupivacaine (NR50 and NR100) and ropivacaine (R50 and R100) intoxication. Isometric contraction data were obtained in basal condition (0.2 Hz), after increasing the frequency of stimulation to 1.0 Hz and after 5, 10 and 15 min of local anesthetic intoxication. Data were analyzed as relative changes of variation. RESULTS: Developed tension was higher with R100 than B100 at D1 (4.3 ± 41.1 vs -57.9 ± 48.1). Resting tension was altered with B50 (-10.6 ± 23.8 vs -4.7 ± 5.0) and R50 (-14.0 ± 20.5 vs -0.5 ± 7.1) between D1 and D3. Maximum rate of tension development was lower with B100 (-56.6 ± 38.0) than R50 (-6.3 ± 37.9) and R100 (-1.9 ± 37.2) in D1. B50, B100 and NR100 modified the maximum rate of tension decline from D1 through D2. Time to peak tension was changed with NR50 between D1 and D2. CONCLUSIONS: Racemic bupivacaine depressed myocardial contractile force more than non-racemic bupivacaine and ropivacaine. Non-racemic and racemic bupivacaine caused myocardial relaxation impairment more than ropivacaine. .
Assuntos
Animais , Masculino , Amidas/farmacologia , Anestésicos Locais/farmacologia , Bupivacaína/farmacologia , Contração Miocárdica/efeitos dos fármacos , Bupivacaína/química , Depressão Química , Tono Muscular/efeitos dos fármacos , Tono Muscular/fisiologia , Contração Miocárdica/fisiologia , Músculos Papilares/efeitos dos fármacos , Músculos Papilares/fisiologia , Ratos Wistar , Valores de Referência , Estereoisomerismo , Fatores de TempoRESUMO
PURPOSE: To study racemic bupivacaine, non-racemic bupivacaine and ropivacaine on myocardial contractility. METHODS: Isolated Wistar papillary muscles were submitted to 50 and 100 mM racemic bupivacaine (B50 and B100), non-racemic bupivacaine (NR50 and NR100) and ropivacaine (R50 and R100) intoxication. Isometric contraction data were obtained in basal condition (0.2 Hz), after increasing the frequency of stimulation to 1.0 Hz and after 5, 10 and 15 min of local anesthetic intoxication. Data were analyzed as relative changes of variation. RESULTS: Developed tension was higher with R100 than B100 at D1 (4.3 ± 41.1 vs -57.9 ± 48.1). Resting tension was altered with B50 (-10.6 ± 23.8 vs -4.7 ± 5.0) and R50 (-14.0 ± 20.5 vs -0.5 ± 7.1) between D1 and D3. Maximum rate of tension development was lower with B100 (-56.6 ± 38.0) than R50 (-6.3 ± 37.9) and R100 (-1.9 ± 37.2) in D1. B50, B100 and NR100 modified the maximum rate of tension decline from D1 through D2. Time to peak tension was changed with NR50 between D1 and D2. CONCLUSIONS: Racemic bupivacaine depressed myocardial contractile force more than non-racemic bupivacaine and ropivacaine. Non-racemic and racemic bupivacaine caused myocardial relaxation impairment more than ropivacaine.(AU)
Assuntos
Animais , Ratos , Bupivacaína/efeitos adversos , Bupivacaína/análise , Ropivacaina/efeitos adversos , Ropivacaina/análise , Contração Miocárdica/efeitos dos fármacos , Cardiotoxicidade , Músculos Papilares , Ratos WistarRESUMO
Se presenta en caso de un varón de 55 años con diagnóstico de insuficiencia mitral severa por ruptura de músculo papilar; los hallazgos operatorios mostraron vegetaciones múltiples en la cabeza del musculo papilar anterolateral con ruptura total del mismo y velos valvulares normales. La histopatología mostró infiltrado inflamatorio polimorfonuclear en el tejido endocárdico y miocárdico, además vegetaciones fibrinosas en la superficie del musculo papilar, el cultivo del tejido resultó positivo a K. pneumoniae, concluyéndose como endocarditis aislada por infección directa del músculo papilar. El paciente recibió tratamiento antibiótico por seis semanas y fue dado de alta a los 45 días del ingreso con grado funcional. (AU)
We report the case of a 55-year old male patient diagnosed of severe mitral valve insufficiency due to rupture of the papilar muscle. Surgical findings included multiple vegetations on the head of the antero-lateral papilar muscle with complete rupture of it and abnormal valve veils. Histoptahology revealed polymorphonuclear infiltrate on the endocardic and myocardic tissues, and fibrinous vegetations on the surface of the papilar muscle. Klebsiella pneumoniae was isolated from the papilar muscle. The patient received 6-weeks of treatment and was discharged after 45 days of being admitted with functional class. (AU)
Assuntos
Humanos , Pessoa de Meia-Idade , Músculos Papilares , Ruptura , Endocardite Bacteriana , Valva MitralRESUMO
Acute primary tricuspid regurgitation (TR) secondary to papillary muscle rupture is an extremely rare clinical situation. We report a 42-year-old male with pulmonary artery hypertension (PAH) secondary to HIV infection, who presented with an acute TR due to spontaneous papillary muscle rupture. He remained in cardiogenic shock despite therapy with inotropic drugs and pulmonary vasodilator therapy. He was subjected to a tricuspid valve replacement. In the postoperative period the patient had severe PAH, which was successfully controlled with inhaled nitric oxide. Tricuspid valve replacement and adjunctive use of pulmonary vasodilator therapy can be a life saving and useful approach in this condition.