RESUMO
The incidence of heart failure (HF) continues to grow and burden our health care system. Electrophysiological aberrations are common amongst patients with heart failure and can contribute to worsening symptoms and prognosis. Targeting these abnormalities with cardiac and extra-cardiac device therapies and catheter ablation procedures augments cardiac function. Newer technologies aimed to improvement procedural outcomes, address known procedural limitations and target newer anatomical sites have been trialled recently. We review the role and evidence base for conventional cardiac resynchronisation therapy (CRT) and its optimisation, catheter ablation therapies for atrial arrhythmias, cardiac contractility and autonomic modulation therapies.
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Terapia de Ressincronização Cardíaca , Ablação por Cateter , Desfibriladores Implantáveis , Insuficiência Cardíaca , Humanos , Terapia de Ressincronização Cardíaca/métodos , Insuficiência Cardíaca/terapia , Arritmias Cardíacas/terapia , Coração , Resultado do TratamentoRESUMO
IMPORTANCE: Randomised trials have shown that catheter ablation (CA) is superior to medical therapy for ventricular tachycardia (VT) largely in patients with ischaemic heart disease. Whether this translates to patients with all forms and stages of structural heart disease (SHD-e.g., non-ischaemic heart disease) is unclear. This trial will help clarify whether catheter ablation offers superior outcomes compared to medical therapy for VT in all patients with SHD. OBJECTIVE: To determine in patients with SHD and spontaneous or inducible VT, if catheter ablation is more efficacious than medical therapy in control of VT during follow-up. DESIGN: Randomised controlled trial including 162 patients, with an allocation ratio of 1:1, stratified by left ventricular ejection fraction (LVEF) and geographical region of site, with a median follow-up of 18-months and a minimum follow-up of 1 year. SETTING: Multicentre study performed in centres across Australia. PARTICIPANTS: Structural heart disease patients with sustained VT or inducible VT (n=162). INTERVENTION: Early treatment, within 30 days of randomisation, with catheter ablation (intervention) or initial treatment with antiarrhythmic drugs only (control). MAIN OUTCOMES, MEASURES, AND RESULTS: Primary endpoint will be a composite of recurrent VT, VT storm (≥3 VT episodes in 24 hrs or incessant VT), or death. Secondary outcomes will include each of the individual primary endpoints, VT burden (number of VT episodes in the 6 months preceding intervention compared to the 6 months after intervention), cardiovascular hospitalisation, mortality (including all-cause mortality, cardiac death, and non-cardiac death) and LVEF (assessed by transthoracic echocardiography from baseline to 6-, 12-, 24- and 36-months post intervention). CONCLUSIONS AND RELEVANCE: The Catheter Ablation versus Anti-arrhythmic Drugs for Ventricular Tachycardia (CAAD-VT) trial will help determine whether catheter ablation is superior to antiarrhythmic drug therapy alone, in patients with SHD-related VT. TRIAL REGISTRY: Australian New Zealand Clinical Trials Registry (ANZCTR) TRIAL REGISTRATION ID: ACTRN12620000045910 TRIAL REGISTRATION URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=377617&isReview=true.
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Ablação por Cateter , Isquemia Miocárdica , Taquicardia Ventricular , Humanos , Antiarrítmicos/uso terapêutico , Volume Sistólico , Estudos Prospectivos , Resultado do Tratamento , Função Ventricular Esquerda , Austrália/epidemiologia , Taquicardia Ventricular/cirurgia , Taquicardia Ventricular/etiologia , Isquemia Miocárdica/cirurgia , Ablação por Cateter/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como AssuntoRESUMO
AIMS: To compare the cost of cardiac stereotactic body radioablation therapy (SBRT) versus catheter ablation for treating ventricular tachycardia (VT). BACKGROUND: Cardiac SBRT is a novel way of treating refractory VT that may be less costly than catheter ablation, owing to its noninvasive, outpatient nature. However, the true costs of either procedure are not well described, which could help inform a more appropriate reimbursement for cardiac SBRT than simply cross-indexing existing procedural rates. METHODS: Process maps were derived for the full patient care cycle of both procedures using time-driven activity-based costing. Step-by-step timestamps were collected prospectively from a 10-patient SBRT cohort and retrospectively from a 59-patient catheter ablation cohort. Individual costs were estimated by multiplying timestamps with capacity cost rates (CCRs) for personnel, space, equipment, consumable, and indirect resources. These were summed into total cost, which for cardiac SBRT was compared with current catheter ablation and single-fraction lung SBRT reimbursements, both potential reference rates for cardiac SBRT. RESULTS: The direct and total procedural costs of cardiac SBRT ($7549 and $10,621) were 49% and 54% less than those of VT ablation ($14,707 and $23,225). These costs were significantly different from current reimbursement for catheter ablation ($22,692) and lung SBRT ($6329). After including hospitalization expenses (≥$15,000), VT ablation costs at least $27,604 more to furnish than cardiac SBRT. CONCLUSIONS: Time-driven activity-based costing (TDABC) can be a helpful tool for assessing healthcare costs, including novel treatment approaches. In addition to its clinical benefits, cardiac SBRT may provide significant cost reduction opportunities for treatment of VT.
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Ablação por Cateter , Radiocirurgia , Taquicardia Ventricular , Antiarrítmicos/uso terapêutico , Ablação por Cateter/métodos , Humanos , Radiocirurgia/métodos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
INTRODUCTION: Despite advances in drug and catheter ablation therapy, long-term recurrence rates for ventricular tachycardia remain suboptimal. Cardiac stereotactic body radiotherapy (SBRT) is a novel treatment that has demonstrated reduction of arrhythmia episodes and favorable short-term safety profile in treatment-refractory patients. Nevertheless, the current clinical experience is early and limited. Recent studies have highlighted variable duration of treatment effect and substantial recurrence rates several months postradiation. Contributing to these differential outcomes are disparate approaches groups have taken in planning and delivering radiation, owing to both technical and knowledge gaps limiting optimization and standardization of cardiac SBRT. METHODS AND FINDINGS: In this report, we review the historical basis for cardiac SBRT and existing clinical data. We then elucidate the current technical gaps in cardiac radioablation, incorporating the current clinical experience, and summarize the ongoing and needed efforts to resolve them. CONCLUSION: Cardiac SBRT is an emerging therapy that holds promise for the treatment of ventricular tachycardia. Technical gaps remain, to be addressed by ongoing research and growing clincial experience.
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Ablação por Cateter , Radiocirurgia , Taquicardia Ventricular , Arritmias Cardíacas , Ablação por Cateter/efeitos adversos , Coração , Humanos , Radiocirurgia/efeitos adversos , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/cirurgiaRESUMO
AIMS: Catheter ablation is an effective treatment for post-infarction ventricular tachycardia (VT). However, some patients may experience a worsened arrhythmia phenotype after ablation. We aimed to determine the prevalence and prognostic impact of arrhythmia exacerbation (AE) after post-infarction VT ablation. METHODS AND RESULTS: A total of 1187 consecutive patients (93% men, median age 68 years, median ejection fraction 30%) who underwent post-infarction VT ablation at six centres were included. Arrhythmia exacerbation was defined as post-ablation VT storm or incessant VT in patients without prior similar events. During follow-up (median 717 days), 426 (36%) patients experienced VT recurrence. Events qualifying as AE occurred in 67 patients (6%). Median times to VT recurrence with and without AE were 238 [interquartile range (IQR) 35-640] days and 135 (IQR 22-521) days, respectively (P = 0.25). Almost half of the patients (46%) who experienced AE experienced it within 6 months of the index procedure. Patients with AE had had longer ablation times during the ablation procedures compared to the rest of the patients (median 42 vs. 34 min, P = 0.02). Among patients with VT recurrence, the risk of death or heart transplantation was significantly higher in patients with than without AE (hazard ratio 1.99, 95% CI 1.28-3.10; P = 0.002) after adjusting for age, gender, ejection fraction, cardiac resynchronization therapy, post-ablation non-inducibility, and post-ablation amiodarone use. CONCLUSION: Arrhythmia exacerbation after ablation of infarct-related VT is infrequent but is independently associated with an adverse long-term outcome among patients who experience a VT recurrence. The mechanisms and mitigation strategies of AE after catheter ablation require further investigation.
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Ablação por Cateter , Taquicardia Ventricular , Idoso , Ablação por Cateter/efeitos adversos , Feminino , Humanos , Infarto , Masculino , Prevalência , Prognóstico , Recidiva , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/epidemiologia , Taquicardia Ventricular/etiologia , Resultado do TratamentoRESUMO
BACKGROUND: Lately, combined main vessel and branch ablation has been recommended during radiofrequency (RF) renal artery denervation. Utilising a validated renal artery phantom model, we aimed (1) to determine thermal injury extent (lesion depth, width and circumferential coverage) and electrode-tissue interface temperature for branch renal artery ablation, and (2) to compare the extent of thermal injury for branch versus main vessel ablation using the same RF System. METHODS: We employed a gel based renal artery phantom model simulating variable vessel diameter and flow, which incorporated a temperature sensitive thermochromic-liquid-crystal (TLC) film for assessing RF ablation thermodynamics. Ablations in a branch renal artery model (n = 32) were performed using Symplicity Spyral (Medtronic, Minneapolis, MN, USA). Lesion dimensions defined by the 51 °C isotherm, circumferential injury coverage, and electrode-tissue interface temperature were measured for all ablations at 60 seconds. RESULTS: Lesion dimensions were 2.13 ± 0.13 mm and 4.13 ± 0.18 mm for depth and width, respectively, involving 23% of the vessel circumference. Maximum electrode-tissue interface temperature was 68.31 ± 2.29 °C. No significant difference in lesion depth between branch and main vessel ablations was found (Δ = 0.02 mm, p = 0.60). However, lesions were wider in the branch (Δ=0.49 mm, p < 0.001) with a larger circumferential coverage compared to main vessel (arc angle of 82.02±3.27° versus 54.90±4.36°, respectively). CONCLUSIONS: In the phantom model, branch ablations were of similar depth but had larger width and circumferential coverage compared to main vessel ablations. Concerning safety, no overheating at the electrode-tissue interface was observed.
Assuntos
Rim , Modelos Cardiovasculares , Artéria Renal , Simpatectomia , Humanos , Rim/irrigação sanguínea , Rim/inervação , Rim/cirurgia , Cristais Líquidos , Artéria Renal/fisiopatologia , Artéria Renal/cirurgiaRESUMO
OBJECTIVES: To assess the clinical efficacy of renal artery denervation (RAD) in our center and to compare the efficacy of two different radiofrequency (RF) systems. BACKGROUND: Several systems are available for RF renal denervation. Whether there is a difference in clinical efficacy among various systems remains unknown. METHODS: Renal artery denervation was performed on 43 patients with resistant hypertension using either the single electrode Symplicity Flex (n = 20) or the multi-electrode EnligHTN system (n = 23). Median post-procedural follow-up was 32.93 months. The primary outcome was post-procedural change in office blood pressure (BP) within 1 year (short-term follow-up). Secondary outcomes were change in office BP between 1 and 4 years (long-term follow-up) and the difference in office BP reduction between the two systems at each follow-up period. RESULTS: For the total cohort, mean baseline office BP (systolic/diastolic) was 174/94 mmHg. At follow-up, mean changes in office BP from baseline were -19.70/-11.86 mmHg (P < 0.001) and -21.90/-13.94 mmHg (P < 0.001) for short-term and long-term follow-up, respectively. The differences in office BP reduction between Symplicity and EnligHTN groups were 8.96/1.23 mmHg (P = 0.42 for systolic BP, P = 0.83 for diastolic BP) and 9.56/7.68 mmHg (P = 0.14 for systolic BP, P = 0.07 for diastolic BP) for short-term and long-term follow-up, respectively. CONCLUSIONS: In our cohort, there was a clinically significant office BP reduction after RAD, which persisted up to 4 years. No significant difference in office BP reduction between the two systems was found.
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Pressão Sanguínea , Ablação por Cateter/instrumentação , Hipertensão/cirurgia , Artéria Renal/inervação , Simpatectomia/instrumentação , Idoso , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Ablação por Cateter/efeitos adversos , Resistência a Medicamentos , Desenho de Equipamento , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Simpatectomia/efeitos adversos , Fatores de Tempo , Resultado do TratamentoRESUMO
Aims: Remote magnetic navigation (RMN) is a safe and effective means of performing ventricular tachycardia (VT) ablation. It may have advantages over manual catheter ablation due to ease of manoeuvrability and catheter stability. We sought to compare the safety and efficacy of RMN vs. manual VT ablation. Methods and results: Retrospective study of procedural outcomes of 139 consecutive VT ablation procedures (69 RMN, 70 manual ablation) in 113 patients between 2009 and 2015 was performed. Remote magnetic navigation was associated with overall higher acute procedural success (80% vs. 60%, P = 0.01), with a trend to fewer major complications (3% vs. 9% P = 0.09). Seventy-nine patients were followed up for a median of 17.0 [interquartile range (IQR) 3.0-41.0] months for the RMN group and 15.5 (IQR 6.5-30.0) months for manual ablation group. In the ischaemic cardiomyopathy subgroup, RMN was associated with longer survival from the composite endpoint of VT recurrence leading to defibrillator shock, re-hospitalization or repeat catheter ablation and all-cause mortality; single-procedure adjusted hazard ratio (HR) 0.240 (95% CI 0.070-0.821) P = 0.023, multi-procedure HR 0.170 (95% CI 0.046-0.632) P = 0.002. In patients with implanted defibrillators, multi-procedure VT-free survival was superior with RMN, HR 0.199 (95% CI 0.060-0.657) P = 0.003. Conclusion: Remote magnetic navigation may improve clinical outcomes after catheter ablation of VT in patients with ischaemic cardiomyopathy. Further prospective clinical studies are required to confirm these findings.
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Cateterismo Cardíaco/métodos , Ablação por Cateter/métodos , Magnetismo/métodos , Tecnologia de Sensoriamento Remoto/métodos , Cirurgia Assistida por Computador/métodos , Taquicardia Ventricular/cirurgia , Potenciais de Ação , Adulto , Idoso , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/mortalidade , Cateteres Cardíacos , Ablação por Cateter/efeitos adversos , Ablação por Cateter/instrumentação , Ablação por Cateter/mortalidade , Técnicas Eletrofisiológicas Cardíacas , Feminino , Frequência Cardíaca , Humanos , Magnetismo/instrumentação , Imãs , Masculino , Pessoa de Meia-Idade , Recidiva , Tecnologia de Sensoriamento Remoto/instrumentação , Estudos Retrospectivos , Fatores de Risco , Cirurgia Assistida por Computador/efeitos adversos , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/mortalidade , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/mortalidade , Taquicardia Ventricular/fisiopatologia , Fatores de Tempo , Resultado do TratamentoRESUMO
AIMS: Longer procedural time is associated with complications in radiofrequency atrial fibrillation ablation. We sought to reduce ablation time and thereby potentially reduce complications. The aim was to compare the dimensions and complications of 40 W/30 s setting to that of high-power ablations (50-80 W) for 5 s in the in vitro and in vivo models. METHODS AND RESULTS: In vitro ablations-40 W/30 s were compared with 40-80 W powers for 5 s. In vivo ablations-40 W/30 s were compared with 50-80 W powers for 5 s. All in vivo ablations were performed with 10 g contact force and 30 mL/min irrigation rate. Steam pops and depth of lung lesions identified post-mortem were noted as complications. A total of 72 lesions on the non-trabeculated part of right atrium were performed in 10 Ovine. All in vitro ablations except for the 40 W/5 s setting achieved the critical lesion depth of 2 mm. For in vivo ablations, all lesions were transmural, and the lesion depths for the settings of 40 W/30 s, 50 W/5 s, 60 W/5 s, 70 W/5 s, and 80 W/5 s were 2.2 ± 0.5, 2.3 ± 0.5, 2.1 ± 0.4, 2.0 ± 0.3, and 2.3 ± 0.7 mm, respectively. The lesion depths of short-duration ablations were similar to that of the conventional ablation. Steam pops occurred in the ablation settings of 40 W/30 s and 80 W/5 s in 8 and 11% of ablations, respectively. Complications were absent in short-duration ablations of 50 and 60 W. CONCLUSION: High-power, short-duration atrial ablation was as safe and effective as the conventional ablation. Compared with the conventional 40 W/30 s setting, 50 and 60 W ablation for 5 s achieved transmurality and had fewer complications.
Assuntos
Queimaduras por Corrente Elétrica/prevenção & controle , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Átrios do Coração/cirurgia , Sistema de Condução Cardíaco/cirurgia , Animais , Queimaduras por Corrente Elétrica/etiologia , Queimaduras por Corrente Elétrica/patologia , Átrios do Coração/lesões , Átrios do Coração/patologia , Sistema de Condução Cardíaco/lesões , Sistema de Condução Cardíaco/patologia , Técnicas In Vitro , Duração da Cirurgia , Doses de Radiação , Ovinos , Estresse MecânicoRESUMO
BACKGROUND: Circuit impedance could affect the safety and efficacy of radiofrequency (RF) ablation. AIM: To perform irrigated RF ablations with graded impedance to compare (1) lesion dimensions and overheated dimensions in fixed power ablations (2) and in power corrected ablations. METHODS: Ablations were performed with irrigated Navistar Thermocool catheter and Stockert EP shuttle generator at settings of 40 W power for 60 seconds, in a previously validated myocardial phantom. The impedance of the circuit was set at 60 Ω, 80 Ω, 100 Ω, 120 Ω, 140 Ω, and 160 Ω. The lesion and overheated dimensions were measured at 53 °C and 80 °C isotherms, respectively. In the second set of ablations, power was corrected according to circuit impedance. RESULTS: In total, 70 ablations were performed. The lesion volume was 72.0 ± 4.8% and 44.7 ± 4.6% higher at 80 Ω and 100 Ω, respectively, compared to that at 120 Ω and it was 15.4 ± 1.2%, 28.1 ± 2.0%, and 38.0 ± 1.8% lower at 140 Ω, 160 Ω, and 180 Ω, respectively. The overheated volume was four times larger when impedance was reduced to 80 Ω from 100 Ω. It was absent at 120 Ω and above. In the power corrected ablations, the lesion volumes were similar to that of 40 W/120 Ω ablations and there was no evidence of overheating. CONCLUSION: The lesion and overheated dimensions were significantly larger with lower circuit impedance during irrigated RF ablation and the lesion size was smaller in high impedance ablations. Power delivery adjusted to impedance using a simple equation improved the consistency of lesion formation and prevented overheating.
Assuntos
Ablação por Cateter/métodos , Impedância Elétrica , Desenho de Equipamento/métodos , Miocárdio , Imagens de Fantasmas , Ablação por Cateter/normas , Desenho de Equipamento/normas , Imagens de Fantasmas/normasRESUMO
INTRODUCTION: Pulmonary vein isolation is an effective treatment for atrial fibrillation. Current endocardial ablation techniques require catheter contact for lesion formation. Inadequate or inconsistent catheter contact results in difficulty with achieving acute and long-term isolation and consequent atrial arrhythmia recurrence. Microwave energy produces radiant heating and therefore can be used for noncontact catheter ablation. We hypothesized that it is possible to design a microwave catheter to produce a circumferential transmural thermal lesion in an in vitro model of a pulmonary vein antrum. METHODS AND RESULTS: A monopole microwave catheter with a sideways firing axially symmetrical heating pattern was designed. Noncontact ablations were performed in a perfused pulmonary vein model constructed from microwave myocardial phantom embedded with a sheet of thermochromic liquid crystal to permit visualization and measurement of thermal lesions from color changes. 1200 J ablations were performed at 150 W for 80 seconds and 120 W for 100 seconds at high (0.8 L/min) and low (0.06 L/min) flow through the modeled pulmonary vein. Myocardial tissue was substituted for the phantom material and ablations repeated at 150 W for 180 seconds and stained with nitro-blue tetrazolium. The catheter was able to induce deep circumferential antral lesions in myocardial phantom and myocardial tissue. Higher power and shorter ablations delivering the same amount of microwave energy resulted in larger lesions with less surface sparing. CONCLUSIONS: A microwave catheter can be designed to produce a circumferential thermal lesion on noncontact ablation and may have possible applications for pulmonary vein isolation.
Assuntos
Cateterismo Cardíaco/instrumentação , Cateteres Cardíacos , Ablação por Cateter/instrumentação , Endocárdio/cirurgia , Micro-Ondas , Modelos Anatômicos , Modelos Cardiovasculares , Veias Pulmonares/cirurgia , Animais , Bovinos , Endocárdio/patologia , Desenho de Equipamento , Fatores de TempoRESUMO
AIMS: Early atrial arrhythmia following atrial fibrillation (AF) ablation is associated with higher recurrence rates. Few studies explore the impact of early AF (EAF) and atrial tachycardia (EAT) on long-term outcomes. Furthermore, EAF/EAT have not been characterized after wide pulmonary vein isolation. We aimed to characterize EAF and EAT and its impact on late AF (LAF) and AT (LAT) after single ring isolation (SRI). METHODS AND RESULTS: We recruited 119 (females 21, age 58 ± 10 years) consecutive patients with AF (paroxysmal 76, persistent 43) undergoing SRI. Early atrial fibrillation/ early atrial tachycardia was defined as AF/AT within 3 months post-procedure (blanking period). Patients were followed for median 2.8[2.2-4] years. Early atrial fibrillation occurred in 28% (n = 33) and EAT in 25% (n = 30). At follow-up, 25% (n = 30) had LAF and 28% (n = 33) had LAT. Patients with EAF and EAT had higher rates of LAF (48 vs. 16%, P<0.0001) and LAT (60 vs. 16%, P < 0.0001), respectively. Independent predictors of LAF were EAF (3.53(1.72-7.29) P = 0.001); and of LAT were EAT (5.62(2.88-10.95) P < 0.0001) and procedure time (1.38/ h(1.07-1.78) P = 0.04). Importantly, EAF did not predict LAT and EAT did not predict LAF. Early atrial fibrillation late in the blanking period was associated with higher rates of LAF (73% for month 3 vs. 25% for Months 1-2, P = 0.004). However, EAT timing did not predict LAT. CONCLUSION: Early atrial fibrillation and EAT are predictive of LAF and LAT, respectively. Early atrial fibrillation late in the blanking period has greater predictive significance for LAF. This timing is not relevant for LAT. Early arrhythmia type and timing have important prognostic significance following SRI. CLINICAL TRIAL REGISTRATION: http://www.anzctr.org.au;ACTRN12606000467538.
Assuntos
Fibrilação Atrial/etiologia , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Veias Pulmonares/cirurgia , Taquicardia Atrial Ectópica/etiologia , Taquicardia Atrial Ectópica/cirurgia , Fibrilação Atrial/diagnóstico , Feminino , Sistema de Condução Cardíaco/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Taquicardia Atrial Ectópica/diagnóstico , Resultado do TratamentoRESUMO
BACKGROUND: Transcatheter aortic valve implantation (TAVI) is a feasible interventional technique for severe aortic stenosis in patients who are deemed inoperable or at high surgical risk. There is limited evidence for the safety and efficacy of TAVI in patients with bicuspid aortic valves (BAV), the most common congenital valve abnormality. In many TAVI trials, patients with BAV have been contraindicated due to concerns surrounding abnormal valve geometry, leading to malfunction or malpositioning. A systematic review and meta-analysis was conducted in order to assess the current evidence and relative merits of TAVI in aortic stenosis patients with BAV. METHOD: From six electronic databases, seven articles including 149 BAV and 2096 non-BAV patients undergoing TAVI were analysed. RESULTS: Between the BAV and no-BAV cohorts, there was no difference in 30-day mortality (8.3% vs 9.0%; P=0.68), post-TAVI mean peak gradients (weighted mean difference, 0.36 mmHg; P=0.55), moderate or severe paravalvular leak (25.7% vs 19.9%; P=0.29), pacemaker implantations (18.5% vs 27.9%; P=0.52), life-threatening bleeding (8.2% vs 13.9%; P=0.33), major bleeding (20% vs 16.8%; P=0.88), conversion to conventional surgery (1.9% vs 1.2%; P=0.18) and vascular complications (8.6% vs 10.1%; P=0.32). CONCLUSIONS: Preliminary short and mid-term pooled data from observation studies suggest that TAVI is feasible and safe in older patients with BAV. While future randomised trials are not likely, larger adequately-powered multi-institutional studies are warranted to assess the long-term durability and complications associated with TAVI in older BAV patients with severe aortic stenosis.
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Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/anormalidades , Doenças das Valvas Cardíacas/cirurgia , Substituição da Valva Aórtica Transcateter/métodos , Valva Aórtica/cirurgia , Doença da Válvula Aórtica Bicúspide , Feminino , Humanos , Masculino , Substituição da Valva Aórtica Transcateter/efeitos adversosRESUMO
Aggregatibacter spp. is a rare cause for cardiac device infections. Due to limited data, the management of Aggregatibacter spp. device infections is not clearly defined but should always involve device removal and prolonged intravenous antibiotics.
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BACKGROUND: Transcatheter renal denervation (RDN) has had inconsistent efficacy and concerns for durability of denervation. We aimed to investigate long-term safety and efficacy of transcatheter microwave RDN in vivo in normotensive sheep in comparison to conventional radiofrequency ablation. METHODS AND RESULTS: Sheep underwent bilateral RDN, receiving 1 to 2 microwave ablations (maximum power of 80-120 W for 240 s-480 s) and 12 to 16 radiofrequency ablations (180 s-240 s) in the main renal artery in a paired fashion, alternating the side of treatment, euthanized at 2 weeks (acute N=15) or 5.5 months (chronic N=15), and compared with undenervated controls (N=4). Microwave RDN produced substantial circumferential perivascular injury compared with radiofrequency at both 2 weeks [area 239.8 (interquartile range [IQR] 152.0-343.4) mm2 versus 50.1 (IQR, 32.0-74.6) mm2, P <0.001; depth 16.4 (IQR, 13.9-18.9) mm versus 7.5 (IQR, 6.0-8.9) mm P <0.001] and 5.5 months [area 20.0 (IQR, 3.4-31.8) mm2 versus 5.0 (IQR, 1.4-7.3) mm2, P=0.025; depth 5.9 (IQR, 1.9-8.8) mm versus 3.1 (IQR, 1.2-4.1) mm, P=0.005] using mixed models. Renal denervation resulted in significant long-term reductions in viability of renal sympathetic nerves [58.9% reduction with microwave (P=0.01) and 45% reduction with radiofrequency (P=0.017)] and median cortical norepinephrine levels [71% reduction with microwave (P <0.001) and 72.9% reduction with radiofrequency (P <0.001)] at 5.5 months compared with undenervated controls. CONCLUSIONS: Transcatheter microwave RDN produces deep circumferential perivascular ablations without significant arterial injury to provide effective and durable RDN at 5.5 months compared with radiofrequency RDN.
Assuntos
Rim , Micro-Ondas , Artéria Renal , Simpatectomia , Animais , Micro-Ondas/uso terapêutico , Micro-Ondas/efeitos adversos , Simpatectomia/métodos , Simpatectomia/efeitos adversos , Artéria Renal/inervação , Rim/inervação , Rim/irrigação sanguínea , Ovinos , Ablação por Cateter/métodos , Ablação por Cateter/efeitos adversos , Fatores de Tempo , Modelos Animais de Doenças , Pressão Sanguínea/fisiologia , Feminino , Ablação por Radiofrequência/métodos , Ablação por Radiofrequência/efeitos adversosRESUMO
Ventricular arrhythmias (VA) can be life-threatening arrhythmias that result in significant morbidity and mortality. Catheter ablation (CA) is an invasive treatment modality that can be effective in the treatment of VA where medications fail. Recurrence occurs commonly following CA due to an inability to deliver lesions of adequate depth to cauterise the electrical circuits that drive VA or reach areas of scar responsible for VA. Stereotactic body radiotherapy is a non-invasive treatment modality that allows volumetric delivery of energy to treat circuits that cannot be reached by CA. It overcomes the weaknesses of CA and has been successfully utilised in small clinical trials to treat refractory VA. This article summarises the current evidence for this novel treatment modality and the steps that will be required to bring it to the forefront of VA treatment.
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BACKGROUND: Voltage mapping in nonischemic cardiomyopathy can fail to identify midmyocardial substrate for ventricular arrhythmias, an important cause of ablation failure. OBJECTIVES: The aim of this study was to assess whether frequency domain analysis of endocardial left ventricular electrograms (EGMs) can better predict the presence of midmyocardial fibrosis (MMF) compared with voltage amplitude. METHODS: Nonischemic cardiomyopathy patients undergoing ventricular tachycardia ablation with registered preprocedural cardiac computed tomography and late iodine enhancement were included. Presence of fibrosis at each EGM site was assessed. Bipolar and unipolar EGMs were transformed to the frequency domain using multitaper spectral analysis. Singular value decomposition of the EGM frequency spectrum was used within a supervised machine learning process to select features to predict the presence of MMF and compare against predictions using voltage amplitude. RESULTS: Thirteen patients were included (median age 57 years [IQR: 28-73 years], median ejection fraction 40% [IQR: 15%-57%]). A total of 6,015 EGM pairs were processed: 2,459 EGM pairs in MMF areas and 3,556 EGM pairs in non-MMF areas. Supervised classifiers were trained with stratified k-fold cross-validation within patients. The distribution of mean area under the curve metrics using frequency features, f, was significantly greater than voltage feature area under the curve metrics, v, (mean f = 0.841 [95% CI: 0.789-0.884] vs mean v = 0.591 [95% CI: 0.530-0.658]; P < 0.001), indicating that frequency-trained classifiers better predicted the presence of MMF. CONCLUSIONS: These data indicate the promising discriminatory value of endocardial EGM frequency content in the assessment of concealed myocardial substrate. Further studies are needed to investigate the importance of the specific frequency features identified.