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1.
J Pharmacol Sci ; 144(3): 123-128, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32921393

RESUMO

We assessed the torsadogenic effects of a novel remyelinating drug clemastine for multiple sclerosis using an in vivo proarrhythmia model of acute atrioventricular block rabbit, since the drug has been demonstrated to suppress the human ether-á-go-go related gene (hERG) K+ channels. Bradycardia was induced by atrioventricular node ablation in isoflurane-anesthetized New Zealand White rabbits (n = 5), and the ventricle was electrically driven at 60 beats/min throughout the experiment, except when extrasystoles appeared. Intravenous administration of clinically relevant dose of 0.03 mg/kg of clemastine and 10-times higher dose of 0.3 mg/kg hardly affected the QT interval or duration of the monophasic action potential (MAP) of the ventricle. Additional administration of clemastine at 3 mg/kg significantly increased the QT interval, MAP duration and the short-term variability of repolarization. Meanwhile, the premature ventricular contractions with R on T phenomenon were observed in 3 out of 5 animals, and torsades de pointes arrhythmias were detected in 1 out of 5 animals. These results suggest that the torsadogenic potential of clemastine is obviously observed in the acute atrioventricular block rabbit, which will not appear within the prescribed dose for multiple sclerosis.


Assuntos
Clemastina/administração & dosagem , Clemastina/efeitos adversos , Síndrome do QT Longo/induzido quimicamente , Esclerose Múltipla/tratamento farmacológico , Torsades de Pointes/induzido quimicamente , Potenciais de Ação/efeitos dos fármacos , Animais , Bloqueio Atrioventricular/fisiopatologia , Bradicardia/fisiopatologia , Relação Dose-Resposta a Droga , Canal de Potássio ERG1/antagonistas & inibidores , Ventrículos do Coração/efeitos dos fármacos , Infusões Intravenosas , Coelhos
2.
Medicine (Baltimore) ; 99(33): e21097, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32871980

RESUMO

INTRODUCTION: Substantial advances in cardiac pacing technology have been developed in the past decades. However, efforts to improve pacing technology to achieve physiological electrical activity, such as with cardiac resynchronization therapy, are underway. Permanent His bundle pacing, which directly stimulates the His-Purkinje network and electrically activates both ventricles, simulates physiological electric activity in the heart, and has been considered an ideal pacing strategy to treat arrhythmias. For patients with atrial fibrillation complicated by third-degree atrioventricular block (AVB), permanent His bundle pacing is a better option than conventional right ventricular apical or septal pacing, the latter of which may be associated with risks, such as heart failure. However, His bundle pacing exhibits some shortcomings, including elevated pacing threshold, dislocation, and abnormal sensing. CASE PRESENTATION: A 69-year-old female patient who had atrial fibrillation (AF) complicated by third-degree AVB and who was treated with permanent His bundle pacing combined with left bundle branch pacing. DIAGNOSIS: AF complicated by third-degree AVB. INTERVENTIONS: We used the left bundle branch as a backup pacing site to overcome any shortcomings related to permanent His bundle pacing. OUTCOMES: The patient recovered well without any events. CONCLUSION: We selected His bundle pacing as the primary pacing, but also used left bundle branch pacing as a backup approach. If His bundle pacing results in an increased sensing threshold, pacing threshold changes, or dislocations, left bundle branch pacing can compensate for dysfunction of permanent deficiencies in His bundle pacing, preserving physiological pacing.


Assuntos
Fibrilação Atrial/complicações , Fibrilação Atrial/terapia , Bloqueio Atrioventricular/complicações , Bloqueio Atrioventricular/terapia , Terapia de Ressincronização Cardíaca/métodos , Idoso , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/fisiopatologia , Bloqueio Atrioventricular/diagnóstico por imagem , Bloqueio Atrioventricular/fisiopatologia , Fascículo Atrioventricular/fisiopatologia , Feminino , Humanos
3.
BMC Cardiovasc Disord ; 20(1): 415, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32928149

RESUMO

BACKGROUND: Methanol is widely used in industry; however, methanol poisoning is not common. In this regard, a number of outbreaks have been recently reported due to inappropriate processing of alcoholic beverages. Shiraz, a city located in the southern part of Iran, faced one of such outbreaks in 2020 during COVID-19 pandemic. There is no sufficient literature on the electrocardiographic findings in methanol toxicity. This study aimed to address this gap in the literature. METHOD: A total of 356 cases with methanol toxicity referred to Shiraz University of Medical Science Tertiary Hospitals (Faghihi and Namazi) in March and April, 2020. The clinical findings of blindness and impaired level of consciousness, lab data such as arterial blood gas, electrolytes, and creatinine, and the most common findings from ECGs were collected. RESULTS: The most common ECG findings were J point elevation (68.8%), presence of U wave (59.2%), QTc prolongation (53.2% in males and 28.6% in females), and fragmented QRS (33.7%). An outstanding finding in this study was the presence of myocardial infarction in 5.3% of the cases. This finding, to the best of our knowledge, has only been reported in a few case reports. Brugada pattern (8.1%) and Osborn wave (3.7%) were the other interesting findings. In multivariate analysis, when confounding factors were adjusted, myocardial infarction, atrioventricular conduction disturbances, sinus tachycardia, and the prolonged QTC > 500 msecond were four independent factors correlated with methanol toxicity severity measured with arterial blood PH on arterial blood gas measurements, with odds ratios of 12.82, 4.46, 2.32 and 3.15 (P < 0.05 for all), respectively. CONCLUSION: Electrocardiographic variations during methanol intoxication are remarkable and well-correlated with poisoning severity. Myocardial infarction was an egregious and yet a common concerning finding in this sample, which need to be ruled out in methanol toxicity.


Assuntos
Bloqueio Atrioventricular/induzido quimicamente , Cegueira/induzido quimicamente , Transtornos da Consciência/induzido quimicamente , Síndrome do QT Longo/induzido quimicamente , Metanol/envenenamento , Infarto do Miocárdio/induzido quimicamente , Solventes/envenenamento , Taquicardia Sinusal/induzido quimicamente , Adolescente , Adulto , Idoso , Bebidas Alcoólicas , Bloqueio Atrioventricular/sangue , Bloqueio Atrioventricular/fisiopatologia , Betacoronavirus , Cegueira/sangue , Cegueira/fisiopatologia , Gasometria , Síndrome de Brugada/sangue , Síndrome de Brugada/induzido quimicamente , Síndrome de Brugada/fisiopatologia , Transtornos da Consciência/sangue , Transtornos da Consciência/fisiopatologia , Infecções por Coronavirus , Eletrocardiografia , Feminino , Contaminação de Alimentos , Humanos , Concentração de Íons de Hidrogênio , Irã (Geográfico) , Síndrome do QT Longo/sangue , Síndrome do QT Longo/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/sangue , Infarto do Miocárdio/fisiopatologia , Pandemias , Pneumonia Viral , Envenenamento/sangue , Envenenamento/fisiopatologia , Fatores Sexuais , Taquicardia Sinusal/sangue , Taquicardia Sinusal/fisiopatologia , Adulto Jovem
4.
Methodist Debakey Cardiovasc J ; 16(2): 162-166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670478

RESUMO

Cardiac involvement of infiltrative disease, such as systemic sclerosis, carries significant morbidity and mortality. All parts of the heart may be affected, although the conduction system is less commonly involved. We report a rare case of systemic sclerosis causing third-degree atrioventricular block and the first known reported case to use cardiac magnetic resonance imaging (CMR) as a diagnostic and prognostic instrument. It is not known whether using cardiac CMR in systemic sclerosis with cardiac involvement could lead to earlier intervention with escalation of medical therapy or earlier referral for transplant evaluation.


Assuntos
Bloqueio Atrioventricular/diagnóstico por imagem , Cardiomiopatias/diagnóstico por imagem , Imagem por Ressonância Magnética , Escleroderma Sistêmico/complicações , Adulto , Bloqueio Atrioventricular/etiologia , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Estimulação Cardíaca Artificial , Cardiomiopatias/etiologia , Cardiomiopatias/fisiopatologia , Cardiomiopatias/terapia , Progressão da Doença , Evolução Fatal , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Masculino , Valor Preditivo dos Testes , Escleroderma Sistêmico/diagnóstico , Escleroderma Sistêmico/tratamento farmacológico , Resultado do Tratamento
5.
J Pharmacol Sci ; 143(4): 330-332, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32499094

RESUMO

We assessed torsadogenic action of risperidone, which can potently inhibit IKr as well as α1-adrenoceptor. A toxic dose of 3 mg/kg of risperidone was intravenously administered over 10 min to chronic atrioventricular block dogs without anesthesia with monitoring Holter electrocardiogram (n = 4). Risperidone increased atrial/ventricular rate for 1-12 h/1-6 h and prolonged QTcF at 6 h after its administration, whereas it did not increase short-term variability of repolarization or induced torsade de pointes. These results suggest that α1-adrenoceptor blockade-dependent, hypotension-induced, reflex-mediated increase of sympathetic tone by risperidone might play a role in protecting the heart from IKr inhibition-associated torsade de pointes.


Assuntos
Bloqueio Atrioventricular , Risperidona/administração & dosagem , Torsades de Pointes/etiologia , Antagonistas de Receptores Adrenérgicos alfa 1 , Animais , Bloqueio Atrioventricular/tratamento farmacológico , Bloqueio Atrioventricular/fisiopatologia , Doença Crônica , Modelos Animais de Doenças , Cães , Hipotensão , Infusões Intravenosas , Reflexo , Risperidona/efeitos adversos
6.
PLoS One ; 15(5): e0233129, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32396565

RESUMO

Temporary pacemakers (TPMs) are usually inserted in an emergency situation. However, there are few reports available regarding which route of access is best or what the most preferred approach is currently in tertiary hospitals. This study aimed to compare procedure times, complication rates, and indications for temporary pacing between the transjugular and transfemoral approaches to TPM placement. We analyzed consecutive patients who underwent TPM placement. Indications; procedure times; and rates of complications including localized infection, any bleeding, and pacing wire repositioning rates were analyzed. A total of 732 patients (361 treated via the transjugular approach and 371 treated via the transfemoral approach) were included. Complete atrioventricular block was the most common cause of TPM placement in both groups, but sick sinus syndrome was especially common in the transjugular approach group. Separately, procedure time was significantly shorter in the transjugular approach group (9.0 ± 8.0 minutes vs. 11.9 ± 9.7 minutes; P < 0.001). Overall complication rates were not significantly different between the two groups, and longer duration of temporary pacing was a risk factor for repositioning. The risk of reposition was significantly increased when the temporary pacing was continued more than 5 days and 3 days in the transjugular approach group and the transfemoral approach group, respectively. The transjugular approach should be considered if the TPM is required for more than 3 days.


Assuntos
Bloqueio Atrioventricular , Estimulação Cardíaca Artificial , Marca-Passo Artificial , Síndrome do Nó Sinusal , Idoso , Idoso de 80 Anos ou mais , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Síndrome do Nó Sinusal/fisiopatologia , Síndrome do Nó Sinusal/cirurgia
7.
Am J Cardiol ; 125(11): 1751-1752, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32279837

RESUMO

In a 27-year-old man the electrocardiogram suggests increased vagal tone, and not intrinsic atrioventricular nodal disease, as the cause of transient atrioventricular block.


Assuntos
Bloqueio Atrioventricular/fisiopatologia , Nervo Vago/fisiopatologia , Adulto , Nó Atrioventricular/fisiopatologia , Eletrocardiografia , Eletrocardiografia Ambulatorial , Humanos , Masculino , Esforço Físico/fisiologia , Síncope
8.
JACC Cardiovasc Interv ; 13(9): 1046-1054, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32305392

RESUMO

OBJECTIVES: The aim of this study was to determine the utility of rapid atrial pacing immediately after transcatheter aortic valve replacement (TAVR) to predict the need for permanent pacemaker implantation (PPI). BACKGROUND: Risk stratification for patients without high-grade atrioventricular block (AVB) after TAVR is imprecise and based on anatomic considerations, electrocardiographic characteristics, and clinical suspicion. A more reliable assessment is necessary to minimize inpatient rhythm monitoring and/or reduce unnecessary PPI. METHODS: Consecutive patients undergoing TAVR at 2 centers were included. After valve implantation in patients without pacemakers who did not have complete heart block or atrial fibrillation, the temporary pacemaker was withdrawn from the right ventricle and placed in the right atrium. Rapid atrial pacing was performed from 70 to 120 beats/min, and patients were assessed for the development of Wenckebach AVB. Patients were then followed for clinical outcomes, including PPI. RESULTS: A total of 284 patients were included. Of these, 130 (45.8%) developed Wenckebach AVB. There was a higher rate of PPI within 30 days of TAVR among the patients who developed Wenckebach AVB (13.1% vs. 1.3%; p < 0.001), with a negative predictive value for PPI in the group without Wenckebach AVB of 98.7%. A greater percentage of patients receiving self-expanding valves required PPI than those receiving a balloon-expandable valves (15.9% vs. 3.7%; p = 0.001), though these rates were still relatively low among patients who did not develop Wenckebach AVB (2.9% and 0.8%). CONCLUSIONS: Atrial pacing post-TAVR is easily performed and can help identify patients who may benefit from extended rhythm monitoring. Patients who did not develop pacing-induced Wenckebach AVB demonstrated an extremely low likelihood of PPI.


Assuntos
Estenose da Valva Aórtica/cirurgia , Bloqueio Atrioventricular/diagnóstico , Técnicas Eletrofisiológicas Cardíacas , Substituição da Valva Aórtica Transcateter/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Bloqueio Atrioventricular/etiologia , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Estimulação Cardíaca Artificial , Tomada de Decisão Clínica , Feminino , Humanos , Itália , Masculino , Ohio , Marca-Passo Artificial , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Procedimentos Desnecessários
9.
PLoS One ; 15(3): e0228913, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32126091

RESUMO

BACKGROUND: Mutations in the human desmin gene (DES) cause autosomal-dominant and -recessive cardiomyopathies, leading to heart failure, arrhythmias, and AV blocks. We analyzed the effects of vascular pressure overload in a patient-mimicking p.R349P desmin knock-in mouse model that harbors the orthologue of the frequent human DES missense mutation p.R350P. METHODS AND RESULTS: Transverse aortic constriction (TAC) was performed on heterozygous (HET) DES-p.R349P mice and wild-type (WT) littermates. Echocardiography demonstrated reduced left ventricular ejection fraction in HET-TAC (WT-sham: 69.5 ± 2.9%, HET-sham: 64.5 ± 4.7%, WT-TAC: 63.5 ± 4.9%, HET-TAC: 55.7 ± 5.4%; p<0.01). Cardiac output was significantly reduced in HET-TAC (WT sham: 13088 ± 2385 µl/min, HET sham: 10391 ± 1349µl/min, WT-TAC: 8097 ± 1903µl/min, HET-TAC: 5793 ± 2517µl/min; p<0.01). Incidence and duration of AV blocks as well as the probability to induce ventricular tachycardias was highest in HET-TAC. We observed reduced mtDNA copy numbers in HET-TAC (WT-sham: 12546 ± 406, HET-sham: 13526 ± 781, WT-TAC: 11155 ± 3315, HET-TAC: 8649 ± 1582; p = 0.025), but no mtDNA deletions. The activity of respiratory chain complexes I and IV showed the greatest reductions in HET-TAC. CONCLUSION: Pressure overload in HET mice aggravated the clinical phenotype of cardiomyopathy and resulted in mitochondrial dysfunction. Preventive avoidance of pressure overload/arterial hypertension in desminopathy patients might represent a crucial therapeutic measure.


Assuntos
Substituição de Aminoácidos , Bloqueio Atrioventricular/fisiopatologia , Cardiomiopatias/fisiopatologia , Desmina/genética , Animais , Bloqueio Atrioventricular/genética , Cardiomiopatias/genética , Variações do Número de Cópias de DNA , DNA Mitocondrial/genética , Modelos Animais de Doenças , Feminino , Técnicas de Introdução de Genes , Heterozigoto , Humanos , Masculino , Camundongos , Volume Sistólico
10.
BMC Cardiovasc Disord ; 20(1): 69, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32039709

RESUMO

BACKGROUND: Complete heart blocks underwent to permanent pacemaker placement are a common complication of tricuspid valve replacement (TVR). If indicated, endocardial placement of a right ventricular (RV) lead is precluded in the presence of mechanical TVR. CASE PRESENTATION: A 20-year-old female patient firstly underwent metallic prosthetic valve operation with tricuspid valve endocarditis in 2014. Three years after the operation, echocardiography revealed dysfunction of the prosthetic valve thus reoperation was decided. In the second operation, the patient underwent a bioprosthesis valve and AV complete block developed in the postoperative period. Left ventricular ejection fraction (EF) was 45% was found on echocardiography. Pacemaker dependence of the patient, it was aimed to place two electrodes into the left ventricle. Electrodes were placed the target two branches in coronary sinus (CS) and right atrium. Univentricular bifocal pacing was enabled to work. CONCLUSION: Electrode placement in the CS is a very good alternative to epicardial surgical lead placement in cases where endocardial lead placement from the right atrium to the RV is contraindicated. In patients with lower left ventricular EF who will be pacemaker dependent, the insertion of two electrodes into the CS to prevent pacemaker is a safe and effective treatment.


Assuntos
Bloqueio Atrioventricular/terapia , Estimulação Cardíaca Artificial , Seio Coronário/fisiopatologia , Frequência Cardíaca , Implante de Prótese de Valva Cardíaca/efeitos adversos , Valva Tricúspide/cirurgia , Potenciais de Ação , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/etiologia , Bloqueio Atrioventricular/fisiopatologia , Feminino , Próteses Valvulares Cardíacas , Implante de Prótese de Valva Cardíaca/instrumentação , Humanos , Volume Sistólico , Resultado do Tratamento , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/fisiopatologia , Função Ventricular Esquerda , Adulto Jovem
11.
BMC Cardiovasc Disord ; 20(1): 89, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093607

RESUMO

BACKGROUND: Acute coronary syndrome (ACS) with high-grade atrioventricular block (HAVB) still has a poor mortality risk, even in the current percutaneous coronary intervention (PCI) era. However, early PCI for ACS with HAVB is associated with improved in-hospital survival and a 6-month survival similar to that of ACS without HAVB. CASE PRESENTATION: A 70-year-old man was admitted to our hospital for ACS with HAVB. ECG showed complete AV block, complete right bundle branch block (CRBBB), and left axis deviation. Cardiac enzymes were elevated. He underwent temporary pacemaker insertion and coronary angiography, which showed severe stenosis of the proximal right coronary artery (RCA), 99% stenosis of the distal RCA with Thrombolysis in Myocardial Infarction (TIMI) grade 2 flow, and total occlusion of the proximal left anterior descending artery (LAD). We performed primary PCI in both the RCA and LAD, which resulted in TIMI grade 3 flow in both. After PCI, the HAVB recovered to normal sinus rhythm with CRBBB; a normal QRS interval returned within three days. The patient was discharged from the hospital without complications. CONCLUSION: In this case of ACS with HAVB, early intensive coronary artery reperfusion resulted in long-term patient survival. The blood supply to the AV node and bilateral bundle branches is complex. Multivessel ischemia may compromise both primary and collateral blood flows to the AV node and septum, resulting in severe conduction impairment. Clinicians performing PCI should be aware of this anatomy and physiology.


Assuntos
Síndrome Coronariana Aguda/terapia , Bloqueio Atrioventricular/diagnóstico , Bloqueio de Ramo/diagnóstico , Eletrocardiografia , Frequência Cardíaca , Intervenção Coronária Percutânea , Potenciais de Ação , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/fisiopatologia , Idoso , Bloqueio Atrioventricular/complicações , Bloqueio Atrioventricular/fisiopatologia , Bloqueio de Ramo/complicações , Bloqueio de Ramo/fisiopatologia , Circulação Colateral , Angiografia Coronária , Circulação Coronária , Stents Farmacológicos , Humanos , Masculino , Intervenção Coronária Percutânea/instrumentação , Valor Preditivo dos Testes , Fatores de Tempo , Resultado do Tratamento
12.
PLoS One ; 15(2): e0229092, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32040499

RESUMO

INTRODUCTION: Sheep have been adopted as a pre-clinical large animal for scientific research as they are good models of cardiac anatomy and physiology, and allow for investigation of pathophysiological processes which occur in the large mammalian heart. There is, however, no defined model of atrioventricular block in sheep to allow for pre-clinical assessment of new cardiac treatment options. We therefore aimed to develop an adult sheep model of atrioventricular block with the focus on future novel applications. METHODS AND RESULTS: We utilized six sheep to undergo two procedures each. The first procedure involved implantation of a single chamber pacemaker into the right ventricular apex, for baseline assessment over four weeks. The second procedure involved creating atrioventricular block by radiofrequency ablation of the His bundle, before holding for a further four weeks. Interrogation of pacemakers and electrocardiograms determined the persistence of atrioventricular block during the follow up period. Pacemakers were inserted, and atrioventricular block created in 6 animals using a conventional approach. One animal died following ablation of the His bundle, due to procedural complications. Four unablated sheep were assessed for baseline data over four weeks and showed 5.53 ± 1.28% pacing reliance. Five sheep were assessed over four weeks following His bundle ablation and showed continuous (98.89 ± 0.81%) ventricular pacing attributable to persistent atrioventricular block, with no major complications. CONCLUSION: We have successfully developed, characterized and validated a large animal model of atrioventricular block that is stable and technically feasible in adult sheep. This model will allow for the advancement of novel therapies, including the development of cell and gene-based therapies.


Assuntos
Bloqueio Atrioventricular/etiologia , Fascículo Atrioventricular/efeitos da radiação , Modelos Animais de Doenças , Animais , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Fascículo Atrioventricular/fisiologia , Ablação por Cateter , Eletrocardiografia , Humanos , Masculino , Marca-Passo Artificial , Ovinos
14.
Chin Med J (Engl) ; 133(2): 134-140, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31880742

RESUMO

BACKGROUND: The symptomatic bradyarrhythmia is Class I indication for pacing therapy which is not a radical cure. The present study aimed to assess the feasibility and to present the initial results of the restricted ablation of the parasympathetic innervation surrounding sinus and atrioventricular (AV) nodes for treating patients with bradyarrhythmia. METHODS: A total of 13 patients with cardiogenic syncope were included from May 2008 to June 2015. Under the guidance of fluoroscopy and /or three-dimensional geometry by 64-slice spiral computed tomography, atrial activation sequence in sinus rhythm was mapped. Chamber geometry was reconstructed manually or automatically using the Niobe II magnetic navigation system integrated with the CARTO-remote magnetic technology (RMT) system. Cardioneuroablation was targeted at the high-amplitude fractionated electrograms surrounding the regions of His bundle and the site with the earliest activation in sinus rhythm. Areas surrounding the sinus node, AV node, and the phrenic nerve were avoided. RESULTS: Thirteen patients completed the studies. Ablation was successfully performed in 12 patients and failed in one. The high-frequency potential was recorded in atrial electrograms surrounding the sinus or AV nodes in all the patients and disappeared in 15 s after radiofrequency applications. The vagal reaction was observed before the improvement of the sinus and AV node function. No complications occurred during the procedures. Patients were followed up for a mean of 13.0 ±â€Š5.9 months. During the follow up ten patients remained free of symptoms, and two patients had a permanent cardiac pacemaker implanted due to spontaneous recurrence of syncope. The heart rate of post-ablation was higher than pre-ablation (69.0 ±â€Š11.0 vs. 49.0 ±â€Š10.0 beats/min, t = 4.56, P = 0.008). The sinus node recovery time, Wenckebach block point, and atrium-His bundle interval were significantly shorter after ablation (1386.0 ±â€Š165.0 vs. 921.0 ±â€Š64.0 ms, t = 7.45, P = 0.002; 590.0 ±â€Š96.0 vs. 464.0 ±â€Š39.0 ms, t = 2.38, P = 0.023; 106.0 ±â€Š5.0 vs. 90.0 ±â€Š12.0 ms, t = 9.80, P = 0.013 before and after ablation procedure, respectively). CONCLUSIONS: Ablation of sinoatrial and AV nodal peripheral fibrillar myocardium electrical activity might provide a new treatment to ameliorate paroxysmal sinus node dysfunction, high degree AV block, and vagal-mediated syncope.


Assuntos
Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Nó Atrioventricular/inervação , Bradicardia/fisiopatologia , Bradicardia/terapia , Ablação por Cateter/métodos , Síndrome do Nó Sinusal/terapia , Adulto , Estimulação Cardíaca Artificial , Eletrocardiografia , Feminino , Átrios do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Síndrome do Nó Sinusal/fisiopatologia , Tomografia Computadorizada Espiral
15.
Am J Cardiol ; 125(1): 107-113, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31732136

RESUMO

The objective of this study was to determine the long-term (>1 year) electrocardiographic (ECG) and clinical outcomes of patients without significant changes in their electrocardiogram after transcatheter aortic valve implantation (TAVI; including patients with pre-existing ECG abnormalities). Among 772 consecutive patients who underwent TAVI in our institution, 397 patients (51%) without new ECG changes were included. TAVI patients were divided into 2 groups according to the presence of pre-existing ECG-conduction disturbances (ECG-CD: 140 patients, non-ECG-CD: 257 patients). Clinical follow-up (median: 35 [22 to 57] months) was complete in all patients but 5 (1.2%), and ECG data were available in 291 patients (84.3% of patients at risk) at a median of 29 (20 to 50) months. In the non-ECG-CD group, most patients (79.8%) remained without significant ECG changes at follow-up, and 16.9% developed first-degree atrioventricular block and/or bundle branch block over time. The rate of permanent pacemaker (PPM) implantation at follow-up was 3.5% (1.1%/year) in the non-ECG-CD group versus 15.7% (5.5%/year) in the ECG-CD group (p <0.001). The presence of pre-existing CD was an independent predictor of PPM at follow-up (hazard ratio [HR] 4.67, 95% confidence interval [CI] 2.15 to 10.16, p <0.001). The ECG-CD group exhibited a higher risk of heart failure hospitalization (non-ECG-CD: 25%, ECG-CD: 29%, log-rank p = 0.01), but not mortality (non-ECG-CD: 50%, ECG-CD: 46%, log-rank p = 0.60) at 5-year follow-up. In conclusion, the ECG remained unchanged in most TAVI recipients without new postprocedural CD. Pre-existing ECG-CD was associated with an increased risk of PPM and heart failure hospitalization at long-term follow-up. These results provide reassuring data in the era of TAVI expanding toward candidates with a longer life expectancy, and highlight the importance of a closer follow-up of those patients with pre-existing ECG-CDs.


Assuntos
Estenose da Valva Aórtica/cirurgia , Bloqueio Atrioventricular/complicações , Bloqueio de Ramo/complicações , Estimulação Cardíaca Artificial/métodos , Eletrocardiografia/métodos , Sistema de Condução Cardíaco/fisiopatologia , Substituição da Valva Aórtica Transcateter/métodos , Idoso , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/fisiopatologia , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Bloqueio de Ramo/fisiopatologia , Bloqueio de Ramo/terapia , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Período Pós-Operatório , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
16.
Innovations (Phila) ; 14(6): 503-508, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31637938

RESUMO

The surgical treatment of atrial fibrillation has evolved over the past 2 decades due to the advent of ablation technology, and the introduction of less invasive surgical approaches. Current devices produce ablation lines that aim to replace the incisions of traditional surgical ablation strategies, such as the Cox-Maze procedure. This has helped to simplify and shorten surgical ablation procedures and has allowed for the development of minimally invasive surgical techniques. This review discusses surgical ablation energy sources and devices, providing background on device characteristics, mechanism of tissue injury, and success in creating transmural lesions.


Assuntos
Técnicas de Ablação/métodos , Fibrilação Atrial/cirurgia , Ablação por Cateter/instrumentação , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/fisiopatologia , Bloqueio Atrioventricular/fisiopatologia , Fontes de Energia Bioelétrica/efeitos adversos , Ablação por Cateter/história , Criocirurgia/efeitos adversos , Criocirurgia/métodos , História do Século XX , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Ablação por Radiofrequência/efeitos adversos , Ablação por Radiofrequência/métodos , Ablação por Radiofrequência/tendências , Ferida Cirúrgica/complicações , Estados Unidos/epidemiologia
17.
PLoS Biol ; 17(10): e3000508, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31593566

RESUMO

CDGSH iron-sulfur domain-containing protein 2 (Cisd2) is pivotal to mitochondrial integrity and intracellular Ca2+ homeostasis. In the heart of Cisd2 knockout mice, Cisd2 deficiency causes intercalated disc defects and leads to degeneration of the mitochondria and sarcomeres, thereby impairing its electromechanical functioning. Furthermore, Cisd2 deficiency disrupts Ca2+ homeostasis via dysregulation of sarco/endoplasmic reticulum Ca2+-ATPase (Serca2a) activity, resulting in an increased level of basal cytosolic Ca2+ and mitochondrial Ca2+ overload in cardiomyocytes. Most strikingly, in Cisd2 transgenic mice, a persistently high level of Cisd2 is sufficient to delay cardiac aging and attenuate age-related structural defects and functional decline. In addition, it results in a younger cardiac transcriptome pattern during old age. Our findings indicate that Cisd2 plays an essential role in cardiac aging and in the heart's electromechanical functioning. They highlight Cisd2 as a novel drug target when developing therapies to delay cardiac aging and ameliorate age-related cardiac dysfunction.


Assuntos
Senilidade Prematura/genética , Envelhecimento/fisiologia , Bloqueio Atrioventricular/genética , Proteínas Relacionadas à Autofagia/genética , Coração/fisiopatologia , Proteínas do Tecido Nervoso/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Senilidade Prematura/metabolismo , Senilidade Prematura/fisiopatologia , Animais , Bloqueio Atrioventricular/diagnóstico por imagem , Bloqueio Atrioventricular/metabolismo , Bloqueio Atrioventricular/fisiopatologia , Proteínas Relacionadas à Autofagia/deficiência , Cálcio/metabolismo , Eletrocardiografia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Coração/fisiologia , Homeostase/fisiologia , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias Cardíacas/genética , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Proteínas do Tecido Nervoso/deficiência , Sarcômeros/fisiologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Transcriptoma
20.
Circ Arrhythm Electrophysiol ; 12(7): e007150, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31216886

RESUMO

BACKGROUND: The etiopathogenesis of electrocardiographic bundle branch and atrioventricular blocks is not fully understood. We investigated familial clustering of cardiac conduction defects and pacemaker insertion in the FHS (Framingham Heart Study). Additionally, we assessed familial clustering of pacemaker insertion in the Danish general population. METHODS: In FHS, we used multivariable-adjusted logistic regression models to investigate the association of parental atrioventricular block (PR interval, ≥0.2 s), complete bundle branch block (QRS, ≥0.12 s), or pacemaker insertion with the occurrence of cardiac conduction abnormalities in their offspring. The Danish nationwide administrative registries were interrogated to assess the relations of parental pacemaker insertion with offspring pacemaker insertion. RESULTS: In FHS (n=371 cases with first-degree atrioventricular block, complete bundle branch block, or pacemaker insertion, and 1471 age- and sex-matched controls), individuals with at least 1 affected parent with a conduction defect had a 1.65-fold odds (odds ratio, 95% CI, 1.32-2.07) for manifesting an atrioventricular block and a 1.62-fold odds (95% CI, 1.08-2.42) for developing a complete bundle branch block. If at least 1 parent had any electrocardiographic conduction defect or pacemaker insertion, the offspring had a 1.62-fold odds (95% CI, 1.31-2.00) for experiencing any of these conditions. In Denmark (n=2 824 199 individuals; 5397 incident pacemaker implantations), individuals with at least 1 first-degree relative with history of pacemaker insertion had a multivariable-adjusted 1.68-fold (incidence rate ratio, 95% CI, 1.49-1.89) risk of undergoing a pacemaker insertion. If the affected relative was ≤45 years of age, the incidence rate ratio was markedly increased to 51.0 (95% CI, 32.7-79.9). CONCLUSIONS: Cardiac conduction blocks and risk for pacemaker insertion cluster within families. A family history of conduction system disturbance or pacemaker insertion should trigger increased awareness of a similar propensity in other family members, especially so when the conduction system disease occurs at a younger age.


Assuntos
Doença do Sistema de Condução Cardíaco/genética , Doença do Sistema de Condução Cardíaco/terapia , Estimulação Cardíaca Artificial , Sistema de Condução Cardíaco/fisiopatologia , Marca-Passo Artificial , Potenciais de Ação , Adulto , Bloqueio Atrioventricular/genética , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Bloqueio de Ramo/genética , Bloqueio de Ramo/fisiopatologia , Bloqueio de Ramo/terapia , Doença do Sistema de Condução Cardíaco/diagnóstico , Doença do Sistema de Condução Cardíaco/fisiopatologia , Estudos de Casos e Controles , Análise por Conglomerados , Dinamarca , Feminino , Predisposição Genética para Doença , Frequência Cardíaca , Hereditariedade , Humanos , Estudos Longitudinais , Masculino , Massachusetts , Pessoa de Meia-Idade , Linhagem , Fenótipo , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
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