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1.
Sci Rep ; 12(1): 13060, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906409

RESUMO

Transradial access has established as preferred access for cardiac catheterization. Difficult vascular anatomy (DVA) is a noticeable threat to procedural success. We retrospectively analyzed 1397 consecutive cardiac catheterizations to estimate prevalence and identify predictors of DVA. In the subclavian-innominate-aortic-region (SIAR), DVA was causing failure in 2.4% during right-sided vs. 0.7% in left-sided forearm-artery-access (FAA) attempts (χ2 = 5.1, p = 0.023). Independent predictors were advanced age [odds ratio (OR) 1.44 per 10-year increase, 95% confidence interval (CI) 1.15 to 1.80, p = 0.001] and right FAA (OR 2.52, 95% CI 1.72 to 3.69, p < 0.001). In the radial-ulnar-brachial region (RUBR), DVA was causing failure in 2.5% during right-sided vs. 1.7% in left-sided FAA (χ2 = 0.77, p = 0.38). Independent predictors were age (OR 1.28 per 10-year increase, 95% CI 1.01 to 1.61, p = 0.04), lower height (OR 1.56 per 10-cm decrease, 95% CI 1.13 to 2.15, p = 0.008) and left FAA (OR 2.15, 95% CI 1.45 to 3.18, p < 0.001). Bilateral DVA was causing procedural failure in 0.9% of patients. The prevalence of bilateral DVA was rare. Predictors in SIAR were right FAA and advanced age and in RUBR, left FAA, advanced age and lower height. Gender, arterial hypertension, body mass, STEMI and smoking were not associated with DVA.


Assuntos
Intervenção Coronária Percutânea , Cateterismo Cardíaco , Angiografia Coronária , Antebraço , Humanos , Prevalência , Artéria Radial , Estudos Retrospectivos
2.
Cardiol Cardiovasc Med ; 6(2): 124-136, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36644510

RESUMO

Background: There is a consensus, that Transradial-Access (TRA) for coronary procedures should be preferred over Transfemoral-Access (TFA). Previously, Forearm-Artery-Angiography (FA) was mainly performed when difficulties during the advancement of the guidewire/-catheter were encountered. We explored the implication of a Standardized Forearm-Angiography (SFA) on procedural success rates of TRA under real-world conditions. Methods: In a single-center study, an all-comers-cohort of 1191 consecutive cases during 1/2020-12/2020 were assessed retrospectively. Primary TFA rates, crossover to TFA, reasons for Forearm-Artery-Access (FAA) failure, the prevalence of kinking at the level of the forearm and the occurrence of vascular complications were analyzed. Major forearm side branches including the common interosseus artery were assessed via SFA. Results: In 1191 consecutive procedures, primary FAA access was attempted in 97.9% of cases. Crossover to TFA after a primary or secondary FAA attempt was necessary in 2.8%. Severe kinking was the most frequent cause of FAA failure and occurred in 3.0% of attempts. A second or third FAA attempt to avoid TFA was successful in 81%. Severe kinking at the level of the forearm was reported in 1.8% of procedures. Conclusion: This is the first study to provide detailed success rates of a primary FAA strategy combined with a Standardized-Forearm-Angiography (SFA) in an all-comers-cohort. While severe kinking proved to be a rare but relevant challenge for FAA success, the prevalence of arterial spasm was marginal. Multiple attempts of FAA to avoid TFA might be safe possibly due to collateral blood supply by the common interosseus artery.

3.
Pacing Clin Electrophysiol ; 32(5): 653-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19422588

RESUMO

INTRODUCTION: Short- and medium-term sinus rhythm (SR) rates after intraoperative radiofrequency ablation to treat permanent atrial fibrillation (AF) are well documented. Is rhythm success stable during a long-term follow-up? METHODS AND RESULTS: A total of 130 patients who had undergone intraoperative radiofrequency cooled-tip endocardial ablation (SICTRA) of permanent AF (mean AF duration 6+/-5 years) concomitant to open heart surgery more than 3 years ago were followed up using electrocardiogram (ECG), Holter-ECG, and echocardiography and compared with 12-month follow-up data. In 55% of patients, only the left atrium and in 45%, both atria were treated using SICTRA. Mitral valve replacement was performed in 21, mitral valve reconstruction in 25, aortic valve replacement in 13, CABG procedures in 51 (including 11 patients with additional mitral valve surgery), and complex procedures in 20 patients. Sixty-nine percent of patients (90/130) were in stable SR after a median period of 48 months, whereas 28% (36/130) were in AF and 3% (4/130) were in atrial flutter. In between the 12-month follow-up and the long-term follow-up, seven patients converted to AF after having documented SR, two patients converted to typical right atrial flutter after being in SR, and two patients from AF to left atrial macroreentry. After left and biatrial SICTRA, SR rates were comparable (73% vs 66%, P = 0.45). Echocardiography revealed 73% of patients in SR to have effective left atrial contraction. CONCLUSIONS: SICTRA restores long-term stable SR in 69% of all patients. Nine percent of patients reconverted back to atrial arrhythmia after having documented SR at 12 months.


Assuntos
Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
4.
J Thorac Cardiovasc Surg ; 129(4): 897-903, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15821661

RESUMO

OBJECTIVES: In patients with multivessel coronary disease, the functional significance of each lesion is often unclear, and preinterventional stress tests may be inconclusive. In this setting, intracoronary pressure measurements may be helpful to define the optimal revascularization strategy. METHODS: Twenty-five consecutive patients (aged 64 +/- 11 years) with multivessel disease, inconclusive stress tests or not performed stress tests, and an angiographically intermediate coronary artery stenosis in at least 1 major vessel underwent intracoronary pressure measurements. Myocardial fractional flow reserve was measured for the intermediate lesions under the condition of maximum hyperemia induced by intravenous adenosine (140 microg x kg(-1) x min(-1). Revascularization strategies based on angiographic information alone were compared with treatment strategies based on fractional flow reserve results. RESULTS: The original recommendation of the revascularization procedure of choice (bypass operation or angioplasty) was changed in 9 patients (36%) on the basis of the results of fractional flow reserve measurements. In 6 more patients, pressure measurements led to a change in the recommended number of anastomoses to be aimed for during the operation. Within diffusely diseased vessels, fractional flow reserve provided an exact segmental resolution of pathologic vessel resistance for optimal graft placement. Significant left main disease was confirmed in 3 of 6 patients and was detected in 3 angiographically unsuspected cases. CONCLUSIONS: In patients with multivessel disease, coronary pressure-derived fractional flow reserve is a valuable tool to guide clinical decision making and support cardiologists and cardiovascular surgeons in the composition of optimal revascularization strategies.


Assuntos
Pressão Sanguínea/fisiologia , Circulação Coronária/fisiologia , Estenose Coronária/cirurgia , Vasos Coronários/fisiopatologia , Revascularização Miocárdica/métodos , Planejamento de Assistência ao Paciente , Adenosina , Adulto , Idoso , Anastomose Cirúrgica , Angioplastia Coronária com Balão , Angiografia Coronária , Ponte de Artéria Coronária , Estenose Coronária/fisiopatologia , Vasos Coronários/patologia , Tomada de Decisões , Teste de Esforço , Feminino , Humanos , Hiperemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego
5.
Chest ; 126(3): 935-41, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15364776

RESUMO

STUDY OBJECTIVES: To assess the practical application and safety of prehospital antithrombotic therapy with the glycoprotein (GP) IIb/IIIa inhibitor eptifibatide for patients with suspected acute coronary syndrome (ACS) or myocardial infarction (MI). DESIGN: Open-labeled pilot study. Patients with typical chest pain who were seen within 6 h of the onset of symptoms were enrolled in the mobile emergency ambulance. Patients were stratified by even/uneven days to receive standard treatment or standard treatment plus an IV bolus of eptifibatide (180 microg/kg body weight) followed by a continuous eptifibatide infusion (2 microg/kg/min). The main outcome measurement was a combination of prehospital or in-hospital death, reinfarction, revascularization of target vessels, and major bleeding complications. RESULTS: A total of 356 patients (age range, 29 to 75 years; women, 24.7%) were included in the analysis. On admission to the hospital, the diagnosis of ACS or MI was confirmed in approximately 60% of patients, and alternative diagnoses were made in 40% of patients. The rates of complications, including fatal and nonfatal complications occurring during transportation and during subsequent hospitalization, were similar in both study groups. The primary end point occurred in 11.8% of patients in the control group, and in 9.6% of those in the eptifibatide group (difference not significant). CONCLUSION: The prehospital administration of the GP IIb/IIIa inhibitor eptifibatide is feasible and safe in patients with clinically suspected ACS and MI. The benefit of this treatment has yet to be established in a large-scale multicenter study.


Assuntos
Trombose Coronária/tratamento farmacológico , Serviços Médicos de Emergência , Infarto do Miocárdio/tratamento farmacológico , Peptídeos/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Idoso , Ambulâncias , Berlim , Trombose Coronária/sangue , Trombose Coronária/mortalidade , Eptifibatida , Estudos de Viabilidade , Feminino , Mortalidade Hospitalar , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/mortalidade , Avaliação de Resultados em Cuidados de Saúde , Peptídeos/efeitos adversos , Projetos Piloto , Inibidores da Agregação Plaquetária/efeitos adversos , Análise de Sobrevida
6.
J Atr Fibrillation ; 4(5): 498, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-28496722

RESUMO

Catheter ablation of atrial fibrillation (AF) has been increasingly used to treat symptomatic patients.Within the last years a growing interest in ablation of persistent AF forms has evolved.Factors that may influence outcome of these procedures to treat persistent AF may be patient-specific (pre-procedural),procedure-related or may involve different post-ablation followup strategies. In this review potential factors predicting recurrence of AF after ablation of persistent AF have been evaluated.In essence, data is limited mostly due to incongruent definitions of persistent AF.Left atrial dimensions, duration of continuous AF and AF cycle length may be patient-specific predictors of outcome. Intra-procedural parameters involved in recurrence prediction may be extent of ablation (effective pulmonary vein isolation appears mandatory) and termination of AF during ablation. Timing and number of cardioversion if persistent AF recurs may predict outcome, as well. Many studies have identified strators for higher recurrence rates in rather small patient groups and need to be further evaluated in larger patient collectives.

7.
Expert Rev Cardiovasc Ther ; 9(8): 1041-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21878048

RESUMO

A novel ablation system consisting of a duty-cycled phased radiofrequency generator and multielectrode mapping and ablation catheters has been introduced to provide ablation therapy in patients with symptomatic atrial fibrillation (AF). Contiguous lesions may be created using anatomically designed ablation catheters maneuvered under fluoroscopic guidance without the use of a 3D electroanatomic mapping system. In addition to pulmonary vein isolation using a circular, decapolar ablation catheter, an ablation strategy targeting complex fractionated atrial electrograms can be performed using two supplemental multiarray catheters specifically designed for ablation at the left atrial septum and within the left atrial body. Procedural times for treating persistent AF using phased radiofrequency are reported as being between 2 and 2.5 h. Freedom from AF ranges between 33 and 75% after a single procedure, which is comparable to other conventional ablation approaches (utilizing electroanatomic mapping). Additional studies in larger patient numbers are needed to understand the long-term maintenance of results and potential adverse effects of the technology.


Assuntos
Técnicas de Ablação , Fibrilação Atrial/cirurgia , Tratamento por Radiofrequência Pulsada , Técnicas de Ablação/tendências , Animais , Átrios do Coração/cirurgia , Humanos
8.
Expert Rev Cardiovasc Ther ; 9(8): 1051-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21878049

RESUMO

Electrical storm (ES) is defined as the occurrence of ≥ three distinct episodes of ventricular arrhythmia (VA) in patients with implanted defibrillators within 24 h. Whereas conventional strategies for acute rhythm stabilization may be effective in some patients the occurrence of ES impairs survival and predicts recurrent VA. Catheter ablation in the setting of ES is complex and involves decisive strategies for individualized ablation approaches adapted to the patient's cardiac abnormalities. Success rates have been documented to be between 79 and 94% in larger studies and effective ablation improves survival and freedom from any VA. Ablation should be considered early in the treatment plan and availability may be improved by interhospital collaboration with highly experienced VA intervention centers.


Assuntos
Arritmias Cardíacas/cirurgia , Ablação por Cateter , Ventrículos do Coração/cirurgia , Animais , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/prevenção & controle , Ablação por Cateter/métodos , Desfibriladores Implantáveis/efeitos adversos , Humanos , Prevenção Secundária
9.
Heart Rhythm ; 8(9): 1357-63, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21699826

RESUMO

BACKGROUND: Atrial fibrillation (AF) is a multifactorial disease of the atria. OBJECTIVE: We studied the differences in the atrial autonomic innervation pattern in subjects with AF compared with sinus rhythm (SR). METHODS: Preparation of postmortem isolated hearts of subjects with documented persistent AF (group A) and SR (group B) included: (1) histological sectioning of predefined areas and quantification of nerve density, and (2) differentiation using immunohistochemistry in adrenergic (sympathetic, tyrosine-hydroxylase antibody), cholinergic (parasympathetic, choline-acetyltransferase antibody) and mixed (adrenergic and cholinergic staining) nerves. RESULTS: Characteristics of subjects in group A (N = 15) and group B (N = 24) did not differ. The mean overall nerve density was similar between groups (A: 0.31 ± 0.25/mm(2); B: 0.35 ± 0.25/mm(2); P = .87). Nerve density appeared higher in the region of the pulmonary vein ostia and antrum (group A: 0.38 ± 0.21/mm(2); group B: 0.32 ± 0.19/mm(2),) compared with other locations of the right and left atrium. A total of 2,224 (group A: 685; group B: 1539) nerves were differentiated using immunohistochemistry. There was a high degree of colocalization of adrenergic and cholinergic nerves (group A: 80% mixed staining, group B: 69% mixed staining). In group A hearts there was a significantly lower density of predominantly cholinergic nerves (0.025 ± 0.052/mm(2) vs. 0.058 ± 0.099/mm(2); P = .008) and a higher density of nerves containing adrenergic components (0.24 ± 0.18/mm(2) vs. 0.18 ± 0.17/mm(2), P = .046). CONCLUSION: Overall autonomic nerve density did not differ between atria with persistent AF compared with SR. On a morphological level, we detected a shift toward a lower density of cholinergic nerves and a higher density of nerves containing adrenergic components in AF subjects.


Assuntos
Fibrilação Atrial/fisiopatologia , Vias Autônomas/fisiopatologia , Átrios do Coração/lesões , Fibras Adrenérgicas , Idoso , Autopsia , Estudos de Casos e Controles , Fibras Colinérgicas , Feminino , Humanos , Imuno-Histoquímica , Masculino
10.
Am J Cardiol ; 105(9): 1235-9, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20403472

RESUMO

The ablation of ventricular tachycardia (VT) can be achieved using anatomically guided approaches using differentiated mapping and ablation techniques. The aim of this study was to evaluate the efficacy of limited linear ablation in the VT exit region identified during sinus rhythm mapping alone. One hundred fifteen consecutive patients presenting for ablation of post-myocardial infarction VT were included. After induction of the target VT during invasive electrophysiology, left ventricular substrate mapping during sinus rhythm to identify scar and border zone on the basis of endocardial bipolar voltage was performed. The exit site of the target VT was regionalized by a simplified vector pace mapping approach and targeted using limited linear ablation within the scar border zone. Seventy-seven percent of all inducible VT was successfully ablated. In 71 patients (62%), no sustained VT was inducible at the end of ablation procedure (complete success). During a median follow-up period of 16 + or - 10 months, 89 patients (77%) had no documented sustained ventricular arrhythmia. Seven patients (2%) had recurrences of the initially ablated VT, and 16 (14%) had new-onset VT. Patients with complete success had a significantly lower number of ventricular arrhythmia reoccurrences than patients with incomplete ablation success (11% vs 37%, p = 0.002). In conclusion, postinfarct VT was effectively ablated in 97% of patients without mapping during ongoing VT using a simplified regional linear ablation approach targeting the scar border zone. Freedom from any ventricular arrhythmia was achieved in 77% of patients during midterm follow-up.


Assuntos
Mapeamento Potencial de Superfície Corporal/normas , Ablação por Cateter , Frequência Cardíaca/fisiologia , Infarto do Miocárdio/complicações , Taquicardia Ventricular/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Mapeamento Potencial de Superfície Corporal/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Recidiva , Reprodutibilidade dos Testes , Estudos Retrospectivos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/etiologia
11.
Expert Rev Cardiovasc Ther ; 7(11): 1341-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19900017

RESUMO

Recently, a novel radiofrequency (RF) ablation system has been developed to perform pulmonary vein (PV) isolation. The system consists of a decapolar, steerable, over-the-wire mapping and ablation catheter combined with a multichannel RF generator that delivers energy in a temperature-controlled, power-limited fashion in both uni- and bi-polar modes. Using this technique, long continuous ablation lesions can be created within the left atrial antrum around the PV ostium. Electrical disconnection of PVs can be achieved in 93% of targeted PVs. Medium-term success is reported as 79.5% of patients with paroxysmal atrial fibrillation (no atrial fibrillation episodes detected during intensive holter monitoring). Ablation procedures using the novel technique are reported to be short (mean procedure duration: 84-201 min), including RF application duration of up to 40 min. Procedure-related complications are rare (1.8%) but the included total patient numbers are small and further studies on larger patient populations are needed.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Veias Pulmonares/cirurgia , Fibrilação Atrial/fisiopatologia , Mapeamento Potencial de Superfície Corporal , Ablação por Cateter/instrumentação , Eletrodos Implantados , Sistema de Condução Cardíaco/cirurgia , Humanos , Ondas de Rádio , Transdutores , Resultado do Tratamento
12.
Eur Heart J ; 28(23): 2909-14, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17956873

RESUMO

AIMS: To demonstrate the safety and efficacy of saline irrigated cooled-tip atrial linear endocardial radiofrequency ablation (SICTRA) concomitant to open-heart surgical procedures in the treatment of permanent atrial fibrillation (AF). METHODS AND RESULTS: Two hundred and twenty-two patients presenting with permanent AF and the need for cardiac surgery were included. In addition to the cardio-surgical procedure [mitral valve (MV) surgery (n = 94), aortic valve replacement (n = 29), bypass surgery (n = 76 including 24 patients with additional MV surgery), and combined procedures (n = 23)] concomitant SICTRA was performed. In 116 patients, the ablation pattern was restricted to the left atrium alone. During the mean follow-up of 29 months, 174 patients (78%) converted to sinusrhythm (SR). In patients with SICTRA restricted to the left atrium conversion rates were not different compared to a biatrial approach (83 vs. 74%, P = 0.47). Thirty-days mortality was found to be 4% (9/222). Post-mortem evaluation revealed 23% of all lesions to be histologically non-transmural. In the overall group, only 4% of patients developed sustained secondary regular atrial arrhythmia. CONCLUSIONS: SICTRA safely and effectively restores stable SR in 78% of patients with permanent AF undergoing open-heart surgery. Rhythm outcome is not influenced by treatment of the right atrium. Sustained regular atrial arrhythmia with the need for invasive treatment strategies occurs in 4% although intra-operative ablation lesions are often non-transmural.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/transplante , Fibrilação Atrial/mortalidade , Ablação por Cateter/métodos , Terapia Combinada/métodos , Ponte de Artéria Coronária/métodos , Seguimentos , Humanos , Período Intraoperatório , Pessoa de Meia-Idade , Valva Mitral/cirurgia
13.
J Cardiovasc Electrophysiol ; 17(1): 18-24, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16426394

RESUMO

UNLABELLED: Ablation of Atrial Tachycardia after Antiatrial Fibrillation Surgery. INTRODUCTION: Surgical treatment of atrial fibrillation (AF) is gaining widespread acceptance. However, therapeutic modalities for secondary regular atrial tachycardia are still empiric. METHODS AND RESULTS: After linear atrial cooled-tip radiofrequency ablation (SICTRA) during cardio-surgical procedures to cure permanent AF, patients with regular atrial tachycardia were identified. Invasive electrophysiology including electroanatomic mapping was performed. Catheter ablation was directed to suppress atrial arrhythmia depending on activation mapping findings. Follow-up was performed after 3 months and then after every 6 months. Of 238 patients, 12 (5.0%) were identified with regular secondary arrhythmias (12 +/- 7 months after surgery) including 9 (3.8%) with persistent forms originating from the right atrium (RA) in six (66%) (isthmus-dependent macroreentry in 4, incisional macroreentry in 1, and RA ectopy in 1). All patients with RA origin of the tachycardia were successfully ablated. Two patients had left atrial (LA)-macroreentry circling around the mitral valve indicating insufficiency of the intraoperative ablation procedure: one patient was successfully ablated within the LA isthmus, in the other patient no complete conduction block could be induced. One patient had LA-macroreentry degenerating into AF, and ablation was not performed. During follow-up (9 +/- 4 months), no recurrences of atrial tachycardias were documented after successful ablation. CONCLUSIONS: Persistent regular "secondary" arrhythmia occurred in 3.8% (9/238) of patients after SICTRA to treat permanent AF. Predominantly (67%; 6/9), the arrhythmia was located in the RA mostly incorporating the RA-isthmus. Catheter ablation was highly effective for RA tachycardia (100%). In three cases (33%), LA-macroreentry was documented and catheter ablation was successful in only one patient (overall success 78%).


Assuntos
Fibrilação Atrial/terapia , Ablação por Cateter/métodos , Cardioversão Elétrica , Taquicardia Atrial Ectópica/cirurgia , Fibrilação Atrial/complicações , Fibrilação Atrial/fisiopatologia , Mapeamento Potencial de Superfície Corporal , Seguimentos , Frequência Cardíaca , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Taquicardia Atrial Ectópica/etiologia , Taquicardia Atrial Ectópica/fisiopatologia , Resultado do Tratamento
14.
J Cardiovasc Electrophysiol ; 16(11): 1246-51, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16302912

RESUMO

INTRODUCTION: Catheter ablation of ventricular tachycardia (VT) in remote myocardial infarction (MI) often requires excessive mapping procedures. Documentation of the electrical substrate via electrogram amplitude may help to identify regions of altered myocardium resembling exit areas of reentrant VTs. METHODS AND RESULTS: A patient with multiple symptomatic monomorphic VTs (biventricular ICD, remote MI) underwent electroanatomic substrate mapping (CARTOtrade mark) for VT ablation. Regions of scar (bipolar electrogram amplitudes or=1.5 mV), and "altered" myocardium (0.5-1.5 mV) were identified. Ablation was directed to regions with "altered" myocardium based on pace map correlation. After ablation the clinical VT did not reoccur. The patient died due to worsening of heart failure 7 days afterward. During postmortal evaluation specified sites of electroanatomic mapping were correlated to histopathological findings. Annotated scar areas were documented to consist of areas with massive fibrosis (>or=80% of mural composition). Ablations were found to span through regions with intermediate fibrosis (21-79%) mapped as "altered" myocardium. Ablation produced transmural coagulation necrosis of mesh-like fibrotic tissue with interspersed remnants of myocardial cells up to a maximum depth of 7.0 mm. Subendocardial intramural bleedings were universal findings 7 days after ablation. CONCLUSIONS: Electroanatomic substrate mapping for VT ablation sufficiently identified regions of scar and normal myocardium. Regions with bipolar electrogram amplitudes between 0.5 and 1.5 mV were found to correlate to areas of "intermediate" fibrosis (21-79%) with only remnant strands of myocardial cells and were identified as target region for ablation. Cooled-tip endocardial radiofrequency ablation lead to transmural coagulation necrosis up to a depth of 7.0 mm.


Assuntos
Ablação por Cateter , Infarto do Miocárdio/complicações , Taquicardia Ventricular/patologia , Taquicardia Ventricular/cirurgia , Idoso , Técnicas Eletrofisiológicas Cardíacas , Evolução Fatal , Humanos , Masculino , Infarto do Miocárdio/patologia , Taquicardia Ventricular/etiologia
15.
Eur Heart J ; 26(17): 1797-803, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15855195

RESUMO

AIMS: Radiofrequency (RF) energy has been extensively used in ablation of arrhythmia but so far no analysis of morphological effects in human left atria has been conducted. METHODS AND RESULTS: We studied 59 ablation lesions from seven patients who died 2 to 22 days after open heart surgery plus intraoperative cooled-tip RF ablation to treat permanent atrial fibrillation (AF) (mean 4, 1-11 years). The ablation area was studied by macroscopy and histological analysis. RF ablation produced clearly delineated coagulation necrosis (up to a depth of 5.5 mm) bordered by an irregular zone of incomplete necrosis and fresh bleeding even 22 days post-operatively. No superficial charring, thrombotic deposition, or perforation was documented. Endocardium and subendocardium displayed oedematic loosening and microfragmentation of connective tissue fibres. Early after ablation (2-6 days), interfibrillar disseminated bleeding and necrosis without tissue removal response were found. Later after ablation (21, 22 days), mild inflammatory reaction and granulation tissue appeared. Twenty-five per cent of all studied lesions, especially in the thick region in between left pulmonary veins and mitral annulus (left atrial isthmus) (86%), were non-transmural. Nerve fibres with different degrees of thermal injury were detected in the pulmonary vein ostial region. CONCLUSION: Intraoperative cooled-tip ablation in AF resulted in coagulation necrosis of endocardium, subendocardium, and the atrial myocardial layer to a depth of 5.5 mm bordered by an irregular zone of incomplete thermal damage. Transmurality of the lesions could only be found in 75% of intraoperatively applied lesions.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter , Idoso , Fibrilação Atrial/patologia , Causas de Morte , Doença Crônica , Endocárdio/patologia , Feminino , Tecido de Granulação/patologia , Átrios do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Período Pós-Operatório
16.
Card Electrophysiol Rev ; 7(3): 259-63, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14739725

RESUMO

Antiarrhythmic surgical procedures to cure atrial fibrillation (AF) are widely used in cardiac surgery. Whereas the Cox maze procedure remains the highly effective gold-standard a variety of different antiarrhythmic procedures aim at reducing the extent and duration of the procedure. Antiarrhythmic procedures are especially effective in patients undergoing mitral valve surgery. In 110 patients with permanent AF undergoing various surgical procedures sinus rhythm was re-established in 75%. Subgroup analyses revealed no significant differences in rhythm or survival after antiarrhythmic intraoperative ablation indicating the usefulness and feasibility of this procedure in patients with a wide range of characteristics. Because conversion usually occurs spontaneously within the first 6 months and antiarrhythmic medication does not increase the incidence of conversion it seems reasonable to wait for spontaneous occurrence of sinus rhythm after antiarrhythmic intraoperative ablation. In patients with permanent AF undergoing open heart surgery additional antiarrhythmic procedures have been shown to be safe and effective.


Assuntos
Fibrilação Atrial/cirurgia , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/mortalidade , Fibrilação Atrial/fisiopatologia , Ablação por Cateter , Cardioversão Elétrica , Átrios do Coração/cirurgia , Sistema de Condução Cardíaco/fisiopatologia , Humanos
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