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1.
Magn Reson Med ; 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38852175

RESUMO

PURPOSE: Wideband phase-sensitive inversion recovery (PSIR) late gadolinium enhancement (LGE) enables myocardial scar imaging in implantable cardioverter defibrillators (ICD) patients, mitigating hyperintensity artifacts. To address subendocardial scar visibility challenges, a 2D breath-hold single-shot electrocardiography-triggered black-blood (BB) LGE sequence was integrated with wideband imaging, enhancing scar-blood contrast. METHODS: Wideband BB, with increased bandwidth in the inversion pulse (0.8-3.8 kHz) and T2 preparation refocusing pulses (1.6-5.0 kHz), was compared with conventional and wideband PSIR, and conventional BB, in a phantom and sheep with and without ICD, and in six patients with cardiac devices and known myocardial injury. ICD artifact extent was quantified in the phantom and specific absorption rate (SAR) was reported for each sequence. Image contrast ratios were analyzed in both phantom and animal experiments. Expert radiologists assessed image quality, artifact severity, and scar segments in patients and sheep. Additionally, histology was performed on the sheep's heart. RESULTS: In the phantom, wideband BB reduced ICD artifacts by 62% compared to conventional BB while substantially improving scar-blood contrast, but with a SAR more than 24 times that of wideband PSIR. Similarly, the animal study demonstrated a considerable increase in scar-blood contrast with wideband BB, with superior scar detection compared with wideband PSIR, the latter confirmed by histology. In alignment with the animal study, wideband BB successfully eliminated severe ICD hyperintensity artifacts in all patients, surpassing wideband PSIR in image quality and scar detection. CONCLUSION: Wideband BB may play a crucial role in imaging ICD patients, offering images with reduced ICD artifacts and enhanced scar detection.

2.
J Cardiovasc Electrophysiol ; 35(1): 206-213, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38018417

RESUMO

Left ventricular assist device (LVAD) implantation is an established treatment for patients with advanced heart failure refractory to medical therapy. However, the incidence of ventricular arrhythmias (VAs) is high in this population, both in the acute and delayed phases after implantation. About one-third of patients implanted with an LVAD will experience sustained VAs, predisposing these patients to worse outcomes and complicating patient management. The combination of pre-existing myocardial substrate and complex electrical remodeling after LVAD implantation account for the high incidence of VAs observed in this population. LVAD patients presenting VAs refractory to antiarrhythmic therapy and catheter ablation procedures are not rare. In such patients, treatment options are extremely limited. Stereotactic body radiation therapy (SBRT) is a technique that delivers precise and high doses of radiation to highly defined targets, reducing exposure to adjacent normal tissue. Cardiac SBRT has recently emerged as a promising alternative with a growing number of case series reporting the effectiveness of the technique in reducing the VA burden in patients with arrhythmias refractory to conventional therapies. The safety profile of cardiac SBRT also appears favorable, even though the current clinical experience remains limited. The use of cardiac SBRT for the treatment of refractory VAs in patients implanted with an LVAD are even more scarce. This review summarizes the clinical experience of cardiac SBRT in LVAD patients and describes technical considerations related to the implementation of the SBRT procedure in the presence of an LVAD.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Radiocirurgia , Taquicardia Ventricular , Humanos , Radiocirurgia/efeitos adversos , Coração Auxiliar/efeitos adversos , Estudos Retrospectivos , Arritmias Cardíacas/cirurgia , Insuficiência Cardíaca/terapia , Resultado do Tratamento , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/radioterapia , Taquicardia Ventricular/cirurgia
3.
Europace ; 26(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38848447

RESUMO

Pulsed field ablation (PFA) is an innovative approach in the field of cardiac electrophysiology aimed at treating cardiac arrhythmias. Unlike traditional catheter ablation energies, which use radiofrequency or cryothermal energy to create lesions in the heart, PFA utilizes pulsed electric fields to induce irreversible electroporation, leading to targeted tissue destruction. This state-of-the-art review summarizes biophysical principles and clinical applications of PFA, highlighting its potential advantages over conventional ablation methods. Clinical data of contemporary PFA devices are discussed, which combine predictable procedural outcomes and a reduced risk of thermal collateral damage. Overall, these technological developments have propelled the rapid evolution of contemporary PFA catheters, with future advancements potentially impacting patient care.


Assuntos
Arritmias Cardíacas , Humanos , Arritmias Cardíacas/cirurgia , Arritmias Cardíacas/terapia , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/diagnóstico , Eletroporação/tendências , Eletroporação/métodos , Resultado do Tratamento , Previsões , Ablação por Cateter/tendências , Ablação por Cateter/métodos , Técnicas de Ablação/tendências , Cateteres Cardíacos , Animais
5.
J Cardiovasc Electrophysiol ; 34(7): 1523-1528, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37293822

RESUMO

INTRODUCTION: Patients with persistent atrial fibrillation (AF) represent a challenging population for rhythm control therapies. Catheter ablation (CA) with pulmonary vein isolation (PVI) is an effective treatment option for the reduction of the arrhythmic burden. Data regarding the comparability between radiofrequency (RF) and cryoballoon ablation (CRYO) in persistent AF are limited. METHODS: This is a prospective, randomized, single-center study designed to compare the efficacy in terms of rhythm control between RF and CRYO in persistent AF. Eligible participants were randomized 2:1 in two arms: RF and CRYO. The primary endpoint of the study was arrhythmia relapse in the early postprocedural period (first 3 months) and in the middle term follow-up (3 months to 12 months). Secondary endpoints included procedure duration, fluoroscopy time, and complications. RESULTS: A total of 199 patients participated in the study (133 patients in the RF arm, 66 in the CRYO arm). No statistically significant difference occurred between the two groups regarding the primary endpoint (recurrences ≤3 months: 35.5% RF vs. 37.9% CRYO, p .755, recurrences >3 months: 26.3% RF vs. 27.3% CRYO, p .999). From the secondary endpoints, CRYO was a procedure of significantly shorter duration (75.15 ± 17.21 in CRYO vs. 136.6 ± 43.33 in RF group, p < .05). CONCLUSION: CRYO and RF ablation appear to be equally effective for rhythm control in patients with persistent AF. CRYO ablation is advantageous in terms of procedure duration.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Criocirurgia , Ablação por Radiofrequência , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Criocirurgia/efeitos adversos , Criocirurgia/métodos , Estudos Prospectivos , Resultado do Tratamento , Veias Pulmonares/cirurgia , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso
6.
J Surg Oncol ; 127(1): 7-10, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36129404

RESUMO

During first outburst of COVID-19, several strategies had been applied for surgical oncology patients to minimize COVID-19 transmission. COVID-19 infection seemed to compromise survival and major complication rates of surgical oncology patients. However, survival, tumor progression and recurrence rates of surgical oncology patients were associated to the consequences of COVID-19 pandemic on their management. In addition, the severity of COVID-19 infections has been downgraded. Therefore, management of surgical oncology patients should be reconsidered.


Assuntos
COVID-19 , Neoplasias , Oncologia Cirúrgica , Humanos , COVID-19/epidemiologia , Pandemias , SARS-CoV-2 , Neoplasias/complicações
7.
Pacing Clin Electrophysiol ; 46(3): 261-263, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36205644

RESUMO

BACKGROUND: Cardiac perforation is an uncommon complication of transvenous pacemaker implantation typically occurring through the apex. CASE SUMMARY: We report a case of patient, in whom ventricular lead perforation was confirmed 6 days after implantation of a dual chamber pacemaker. The ventricular lead was perforating the ventricular septum, near the left anterior descending artery, exiting the left ventricle. The patient underwent cardiac surgery due to the lead perforation as also as aortic valve replacement due to concomitant severe aortic valve stenosis. DISCUSSION: The presented case report is a rare case of lead perforation through the LV and illustrates that lead perforation can still occur even after placement of the RV lead in septal position and even through the thick ventricular wall.


Assuntos
Marca-Passo Artificial , Septo Interventricular , Humanos , Ventrículos do Coração , Septo Interventricular/diagnóstico por imagem , Marca-Passo Artificial/efeitos adversos , Valva Aórtica/cirurgia , Artérias
8.
Curr Cardiol Rep ; 25(6): 535-542, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37115434

RESUMO

PURPOSE OF REVIEW: Imaging plays a crucial role in the therapy of ventricular tachycardia (VT). We offer an overview of the different methods and provide information on their use in a clinical setting. RECENT FINDINGS: The use of imaging in VT has progressed recently. Intracardiac echography facilitates catheter navigation and the targeting of moving intracardiac structures. Integration of pre-procedural CT or MRI allows for targeting the VT substrate, with major expected impact on VT ablation efficacy and efficiency. Advances in computational modeling may further enhance the performance of imaging, giving access to pre-operative simulation of VT. These advances in non-invasive diagnosis are increasingly being coupled with non-invasive approaches for therapy delivery. This review highlights the latest research on the use of imaging in VT procedures. Image-based strategies are progressively shifting from using images as an adjunct tool to electrophysiological techniques, to an integration of imaging as a central element of the treatment strategy.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Humanos , Taquicardia Ventricular/diagnóstico por imagem , Taquicardia Ventricular/cirurgia , Arritmias Cardíacas , Coração , Frequência Cardíaca , Ablação por Cateter/métodos , Resultado do Tratamento
9.
J Electrocardiol ; 76: 1-10, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36370545

RESUMO

Atrial cardiomyopathy (AC) is an evolving pathophysiological entity that has expanded our understanding regarding the atrium and its role in arrhythmogenesis and cardiac thromboembolism. The pathological myocardium in AC promotes arrhythmogenesis through mechanical dysfunction (hypocontractility, fibrosis), adverse alterations of the endothelium and secretion of prothrombotic factors (IL-6, IL-8, TNF-a). 'Red flags', indicative of AC, can be recognized either non-invasively by electrocardiography, echocardiography and cardiac magnetic resonance imaging or invasively by high-density electroanatomical mapping as low bipolar voltage areas of the affected myocardium. Signs of AC have been strongly associated with an increased risk of ischemic stroke, even embolic strokes of undetermined source, regardless of the coexistence of atrial fibrillation (AF). The underlying existence of AC has been negatively correlated with the success rate of catheter ablation of AF. The clinical value of AC is the provision of a novel pathway regarding the potential mechanisms of cerebrovascular events of cardiac thromboembolic origin. In addition, AC may serve as a risk stratification tool to predict the long-term responders of AF catheter ablation.


Assuntos
Fibrilação Atrial , Cardiomiopatias , Acidente Vascular Cerebral , Tromboembolia , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/diagnóstico , Acidente Vascular Cerebral/etiologia , Fatores de Risco , Eletrocardiografia , Átrios do Coração , Tromboembolia/prevenção & controle , Tromboembolia/complicações , Anticoagulantes/uso terapêutico
10.
Int J Neurosci ; 133(6): 612-620, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34228947

RESUMO

BACKGROUND: Evidence suggests that fluctuations of cortisol and physiological parameters can emerge during the course of mild Traumatic Brain Injury (mTBI). OBJECTIVE: To investigate fluctuations of cortisol and physiological parametersduring the acute phase of mTBI in hospitalized patients. METHODS: 30 participants (19 patients with mTBI and 11 controls) were examined for saliva cortisol dynamics, heart rate (HR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP) and body temperature (BT) fluctuations for four consecutive days. Also, the participants completed the Athens Insomnia Scale and Epworth Sleepiness Scales, in order to check for sleep problems. RESULTS: Patients showed elevated levels of cortisol relative to controls (peak at 8 am and lowest levels at 12 am), as well as for most physiological parameters. MAP was significantly higher for patients throughout the measurement period, and BT was elevated for patients relative to controls at almost all measurements of the first and second day. Mean HR tended to track at non-significantly higher levels for the mTBI group. Patients' sleepiness and insomnia values (ESS and AIS) were initially significantly higher relative to controls but the difference dissipated by day 4. CONCLUSION: The increase in absolute values of cortisol and physiological parameters measurements, indicates that in the acute phase of mTBI, a stressful process is activated which may affect sleep quality as well.Supplemental data for this article is available online at at doi: 10.1080/00207454.2021.1951264.


Assuntos
Concussão Encefálica , Lesões Encefálicas , Distúrbios do Início e da Manutenção do Sono , Humanos , Hidrocortisona , Saliva , Sonolência
11.
J Cardiovasc Electrophysiol ; 33(6): 1116-1124, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35347799

RESUMO

INTRODUCTION: The optimal strategy after a failed ablation for persistent atrial fibrillation (perAF) is unknown. This study evaluated the value of an anatomically guided strategy using a systematic set of linear lesions with adjunctive ethanol infusion into the vein of Marshall (Et-VOM) in patients referred for second perAF ablation procedures. METHODS AND RESULTS: Patients with perAF who underwent a second procedure were grouped according to the two strategies. The first strategy was an anatomically guided approach using systematic linear ablation with adjunctive Et-VOM, with bidirectional blocks at the posterior mitral isthmus (MI), roof, and cavotricuspid isthmus (CTI) as the procedural endpoint (Group I). The second one was an electrophysiology-guided strategy, with atrial tachyarrhythmia termination as the procedural endpoint (Group II). Arrhythmia behavior during the procedure guided the ablation strategy. Groups I and II consisted of 96 patients (65 ± 9 years; 71 men) and 102 patients (63 ± 10 years; 83 men), respectively. Baseline characteristics were comparable. In Group I, Et-VOM was successfully performed in 91/96 (95%), and procedural endpoint (bidirectional block across all three anatomical lines) was achieved in 89/96 (93%). In Group II, procedural endpoint (atrial tachyarrhythmia termination) was achieved in 80/102 (78%). One-year follow-up demonstrated Group I (21/96 [22%]) experienced less recurrence compared to Group II (38/102 [37%], Log-rank p = .01). This was driven by lower AT recurrence in Group I (Group I: 10/96 [10%] vs. Group II: 29/102 [28%]; p = .002). CONCLUSION: Anatomically guided strategy with adjunctive Et-VOM is superior to an electrophysiology-guided strategy for second procedures in patients with perAF at 1-year follow-up.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Eletrofisiologia Cardíaca , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Etanol/efeitos adversos , Humanos , Masculino , Veias Pulmonares/cirurgia , Recidiva , Taquicardia , Resultado do Tratamento
12.
Heart Fail Rev ; 27(6): 2067-2076, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35776368

RESUMO

Left ventricular non-compaction cardiomyopathy (LVNC) is a congenital heart disease with autosomal dominant inheritance. This review aims to summarize the existing data about the predictors of fatal arrhythmias in patients with LVNC. Medline and Cochrane library databases were searched from inception to November 2021 for articles on LVNC. The reference lists of the relevant research studies as well as the relevant review studies and meta-analyses were also searched. Clinical symptoms and electrocardiogram findings such as left bundle branch block are significantly associated with ventricular arrhythmias. Other non-invasive tools such as Holter monitoring, echocardiography, and cardiac magnetic resonance (CMR) can provide additional value for risk stratification. CMR-derived left and right ventricular ejection fraction, left ventricular end-diastolic diameter, late gadolinium enhancement, and non-compacted to compacted myocardium ratio are predictive of ventricular arrhythmias. An electrophysiological study can provide additional prognostic data in patients with LVNC who are at moderate risk of ventricular arrhythmias. Risk stratification of LVNC patients with no prior history of a fatal arrhythmic event remains challenging. Symptoms assessment, electrocardiogram, Holter monitoring, and cardiac imaging should be performed on every patient, while an electrophysiological study should be performed for moderate-risk patients. Large cohort studies are needed for the construction of score models for arrhythmic risk stratification purposes.


Assuntos
Cardiomiopatias , Meios de Contraste , Cardiomiopatias/diagnóstico , Gadolínio , Humanos , Valor Preditivo dos Testes , Volume Sistólico , Função Ventricular Esquerda/fisiologia , Função Ventricular Direita
13.
Heart Fail Rev ; 27(6): 2095-2118, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36045189

RESUMO

Despite the strict indications for cardiac resynchronization therapy (CRT) implantation, a significant proportion of patients will fail to adequately respond to the treatment. This systematic review aims to present the existing evidence about the role of cardiac magnetic resonance (CMR) in identifying patients who are likely to respond better to the CRT. A systematic search in the MedLine database and Cochrane Library from their inception to August 2021 was performed, without any limitations, by two independent investigators. We considered eligible observational studies or randomized clinical trials (RCTs) that enrolled patients > 18 years old with heart failure (HF) of ischaemic or non-ischaemic aetiology and provided data about the association of baseline CMR variables with clinical or echocardiographic response to CRT for at least 3 months. This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA Statement). Following our search strategy, 47 studies were finally included in our review. CMR appears to have an additive role in identifying the subgroup of patients who will respond better to CRT. Specifically, the presence and the extent of myocardial scar were associated with increased non-response rates, while those with no scar respond better. Furthermore, existing data show that scar location can be associated with CRT response rates. CMR-derived markers of mechanical desynchrony can also be used as predictors of CRT response. CMR data can be used to optimize the position of the left ventricular lead during the CRT implantation procedure. Specifically, positioning the left ventricular lead in a branch of the coronary sinus that feeds an area with transmural scar was associated with poorer response to CRT. CMR can be used as a non-invasive optimization tool to identify patients who are more likely to achieve better clinical and echocardiographic response following CRT implantation.


Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca , Adolescente , Terapia de Ressincronização Cardíaca/métodos , Cicatriz/patologia , Cicatriz/terapia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/terapia , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Resultado do Tratamento
14.
Rev Cardiovasc Med ; 23(2): 44, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35229535

RESUMO

Brugada syndrome (BrS) is a complex arrhythmogenic disease displaying electrical and micro-structural abnormalities mainly located at the epicardium of the right ventricular outflow tract (RVOT). It is well-known that fibrosis, fatty infiltration, inflammation and reduced gap junction expression have been demonstrated at the epicardial anterior aspect of the RVOT providing the arrhythmogenic substrate for ventricular arrhythmic events in BrS. A number of models have been proposed for the risk stratification of patients with BrS. Endocardial unipolar electroanatomical mapping is an emerging tool that has been reintroduced to identify and quantify epicardial electrical abnormalities. Interestingly, current findings correlate the presence of large-sized endocardial unipolar electroanatomical abnormalities with either ventricular fibrillation inducibility during programmed ventricular stimulation or symptom status. This review aims to present existing data about the role of endocardial unipolar electroanatomical mapping for the identification of RVOT epicardial abnormalities as well as its potential clinical implications in risk stratification of BrS.


Assuntos
Síndrome de Brugada , Síndrome de Brugada/diagnóstico , Eletrocardiografia/métodos , Endocárdio , Ventrículos do Coração , Humanos , Medição de Risco
15.
Rev Cardiovasc Med ; 23(3): 103, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35345270

RESUMO

Outflow tract (OT) premature ventricular complexes (PVCs) are being recognized as a common and often troubling, clinical electrocardiographic finding. The OT areas consist of the Right Ventricular Outflow Tract (RVOT), the Left Ventricular Outflow Tract (LVOT), the Aortomitral Continuity (AMC), the aortic cusps and the Left Ventricular (LV) summit. By definition, all OT PVCs will exhibit an inferior QRS axis, defined as positive net forces in leads II, III and aVF. Activation mapping using the contemporary 3D mapping systems followed by pace mapping is the cornerstone strategy of every ablation procedure in these patients. In this mini review we discuss in brief all the modern mapping and ablation modalities for successful elimination of OT PVCs, along with the potential advantages and disadvantages of each ablation technique.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Complexos Ventriculares Prematuros , Ablação por Cateter/efeitos adversos , Eletrocardiografia/métodos , Ventrículos do Coração , Humanos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/cirurgia , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/cirurgia
16.
Medicina (Kaunas) ; 58(7)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35888668

RESUMO

One of the most serious late side effects of irradiation is the promotion of tumorigenesis. Radiation-induced esophageal cancer (RIEC) can arise in a previously irradiated field, mostly in patients previously irradiated for thoracic malignancies such as breast cancer, Hodgkin and non-Hodgkin lymphomas, head and neck cancers, lung cancer, or previous esophageal cancer. RIEC is rare and accounts for less than 1% of all carcinomas of the esophagus. There are little data available in the current literature regarding pathogenesis, diagnosis, treatment, and outcome of esophageal cancer developed in a previously irradiated field. RIEC seems to represent a biologically aggressive disease with a poor prognosis. Although it is difficult to perform radical surgery on a previously irradiated field, R0 resection remains the mainstay of treatment. The use of neoadjuvant and adjuvant chemoradiotherapy remains very helpful in RIEC, similarly to conventional esophageal cancer protocols. The aim of this article is to elucidate this rare but challenging entity.


Assuntos
Neoplasias Esofágicas , Neoplasias Induzidas por Radiação , Quimiorradioterapia Adjuvante/efeitos adversos , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/radioterapia , Humanos , Terapia Neoadjuvante , Neoplasias Induzidas por Radiação/etiologia , Prognóstico
17.
J Cardiovasc Electrophysiol ; 32(2): 547-550, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33179375

RESUMO

Coronary artery injury is a rare complication of catheter ablation in the right ventricular outflow tract (RVOT). Furthermore, acute myocardial ischemia usually causes polymorphic ventricular tachycardia (VT) or ventricular fibrillation. We herein describe a case in which catheter ablation for VT originating from the RVOT provoked ischemia-related VTs due to acute occlusion of the left anterior descending artery.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Ablação por Cateter/efeitos adversos , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Eletrocardiografia , Humanos , Isquemia , Taquicardia Ventricular/diagnóstico por imagem , Taquicardia Ventricular/etiologia
18.
J Cardiovasc Electrophysiol ; 32(3): 570-577, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33476463

RESUMO

BACKGROUND: Ultralow temperature cyroablation (ULTC) is designed to create focal, linear, and circumferential lesions. The aim of this study was to assess the safety, efficacy, and durability of atrial and ventricular ULTC lesions in preclinical large animal models. METHODS AND RESULTS: The ULTC system uses nitrogen near its liquid-vapor critical point to cool 11-cm ablation catheters. The catheter can be shaped to specific anatomies using pre-shaped stylets. ULTC was used in 11 swine and four sheep to create atrial (pulmonary vein isolation and linear ablation) and ventricular lesions. Acute and 90-day success were evaluated by intracardiac mapping and histologic examination. Cryoadherence was observed during all ULTC applications, ensuring catheter stability at target locations. Local electrograms were completely eliminated immediately after the first single-shot ULTC application in 49 of 53 (92.5%) atrial and in 31 of 32 (96.9%) ventricular applications. Lesion depth as measured on histology preparations was 1.96 ± 0.8 mm in atrial and 5.61 ± 2.2 mm in ventricular lesions. In all animals, voltage maps and histology demonstrated transmural and durable lesions without gaps, surrounded by intact collagen fibers without injury to surrounding tissues. Transient coronary spasm could be provoked with endocardial ULTC in the left ventricle in close proximity to a coronary artery. CONCLUSIONS: ULTC created effective and efficient atrial and ventricular lesions in vivo without procedural complications in two large animal models. ULTC lesions were transmural, contiguous, and durable over 3 months.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Criocirurgia , Veias Pulmonares , Animais , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Criocirurgia/efeitos adversos , Átrios do Coração/cirurgia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/cirurgia , Veias Pulmonares/cirurgia , Ovinos , Suínos , Temperatura
19.
J Cardiovasc Electrophysiol ; 32(8): 2216-2224, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34223662

RESUMO

INTRODUCTION: Ultrahigh-density mapping for ventricular tachycardia (VT) is increasingly used. However, manual annotation of local abnormal ventricular activities (LAVAs) is challenging in this setting. Therefore, we assessed the accuracy of the automatic annotation of LAVAs with the Lumipoint algorithm of the Rhythmia system (Boston Scientific). METHODS AND RESULTS: One hundred consecutive patients undergoing catheter ablation of scar-related VT were studied. Areas with LAVAs and ablation sites were manually annotated during the procedure and compared with automatically annotated areas using the Lumipoint features for detecting late potentials (LP), fragmented potentials (FP), and double potentials (DP). The accuracy of each automatic annotation feature was assessed by re-evaluating local potentials within automatically annotated areas. Automatically annotated areas matched with manually annotated areas in 64 cases (64%), identified an area with LAVAs missed during manual annotation in 15 cases (15%), and did not highlight areas identified with manual annotation in 18 cases (18%). Automatic FP annotation accurately detected LAVAs regardless of the cardiac rhythm or scar location; automatic LP annotation accurately detected LAVAs in sinus rhythm, but was affected by the scar location during ventricular pacing; automatic DP annotation was not affected by the mapping rhythm, but its accuracy was suboptimal when the scar was located on the right ventricle or epicardium. CONCLUSION: The Lumipoint algorithm was as/more accurate than manual annotation in 79% of patients. FP annotation detected LAVAs most accurately regardless of mapping rhythm and scar location. The accuracy of LP and DP annotations varied depending on mapping rhythm or scar location.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Arritmias Cardíacas , Cicatriz/diagnóstico por imagem , Cicatriz/etiologia , Técnicas Eletrofisiológicas Cardíacas , Humanos , Taquicardia Ventricular/diagnóstico por imagem , Taquicardia Ventricular/etiologia
20.
J Cardiovasc Electrophysiol ; 32(9): 2451-2461, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34314087

RESUMO

INTRODUCTION: Human atria comprise distinct layers. One layer can bypass another, and lead to a downstream centrifugal propagation at their interface. We sought to characterize anatomical substrates, electrophysiological properties, and ablation outcomes of "pseudo-focal" atrial tachycardias (ATs), defined as macroreentrant ATs mimicking focal ATs. METHODS AND RESULTS: We retrospectively analyzed left atrial ATs showing centrifugal propagation with postpacing intervals (PPIs) after entrainment pacing suggestive of a macroreentrant mechanism. A total of 22 patients had pseudo-focal ATs consisting of 15 perimitral and 7 roof-dependent flutters. A low-voltage area was consistently found at the collision site and colocalized with distinct anatomical structures like the: (1) coronary sinus-great cardiac vein bundle (27%), (2) vein of Marshall bundle (18%), (3) Bachmann bundle (27%), (4) septopulmonary bundle (18%), and (5) fossa ovalis (9%). The mean missing tachycardia cycle length (TCL) was 65 ± 31 ms (22%) on the endocardial activation map. PPI was 0 [0-15] ms and 0 [0-21] ms longer than TCL at the breakthrough site and the opposite site, respectively. While feasible in 21 pseudo-focal ATs (95%), termination was better achieved by blocking the anatomical isthmus than ablating the breakthrough site [20/21 (95%) vs. 1/5 (20%); p < .001]. CONCLUSION: Perimitral and roof-dependent flutters with centrifugal propagation are favored by a low-voltage area located at well-identified anatomical structures. Comprehensive entrainment pacing maneuvers are crucial to distinguish pseudo-focal ATs from true focal ATs. Blocking the anatomical isthmus is a better therapeutic option than ablating the breakthrough site.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Taquicardia Supraventricular , Fibrilação Atrial/cirurgia , Átrios do Coração/cirurgia , Humanos , Estudos Retrospectivos , Taquicardia , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/cirurgia , Resultado do Tratamento
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