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Background: Atrial fibrillation (AF) is considered the most common human arrhythmia. In nonvalvular AF, around 99% of thrombi are formed in the left atrial appendage (LAA). Nevertheless, there is not a consensus in the community about the relevant factors to stratify the AF population according to thrombogenic risk. Objective: To demonstrate the need for combining left atrial morphological and haemodynamics indices to improve the thrombogenic risk assessment in nonvalvular AF patients. Methods: A cohort of 71 nonvalvular AF patients was analysed. Statistical analysis, regression models, and random forests were used to analyse the differences between morphological and haemodynamics parameters, extracted from computational simulations built on 3D rotational angiography images, between patients with and without transient ischemic attack (TIA) or cerebrovascular accident (CVA). Results: The analysis showed that models composed of both morphological and haemodynamic factors were better predictors of TIA/CVA compared with models based on either morphological or haemodynamic factors separately. Maximum ostium diameter, length of the centreline, blood flow velocity within the LAA, oscillatory shear index, and time average wall shear stress parameters were found to be key risk factors for TIA/CVA prediction. In addition, TIA/CVA patients presented more flow stagnation within the LAA. Conclusion: Thrombus formation in the LAA is the result of multiple factors. Analyses based only on morphological or haemodynamic parameters are not precise enough to predict such a phenomenon, as demonstrated in our results; a better patient stratification can be obtained by jointly analysing morphological and haemodynamic features.
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Apêndice Atrial , Fibrilação Atrial , Apêndice Atrial/diagnóstico por imagem , Fibrilação Atrial/complicações , Velocidade do Fluxo Sanguíneo , Ecocardiografia Transesofagiana/métodos , Humanos , Medição de RiscoRESUMO
BACKGROUND: Subcutaneous implantable cardioverter defibrillators (S-ICDs) avoid complications secondary to transvenous leads, but inappropriate shocks (ISs) are frequent. Furthermore, IS data from patients with Brugada syndrome (BrS) with an S-ICD are scarce. OBJECTIVE: We aimed to establish the frequency and predictors of IS in this population. METHODS: We analyzed the clinical and electrocardiographic characteristics, automated screening test data, device programming, and IS occurrence in adult patients with BrS with an S-ICD. RESULTS: Thirty-nine patients were enrolled (69% male, mean age at diagnosis 46 ± 13 years, mean age at implantation 48 ± 13 years). During a mean follow-up of 26 ± 21 months, 18% patients experienced IS. Patients with IS were younger at the time of diagnosis (36 ± 8 vs. 48 ± 13 years, p = .018) and S-ICD implantation (38 ± 9 vs. 50 ± 23 years, p = .019) and presented with spontaneous type 1 Brugada electrocardiogram pattern more frequently at diagnosis or during follow-up (71% vs. 25%, p = .018). During automated screening tests, patients with IS showed lower QRS voltage in the primary vector in the supine position (0.58 ± 0.26 vs. 1.10 ± 0.35 mV, p = .011) and lower defibrillator automated screening score in the primary vector in the supine (123 ± 165 vs. 554 ± 390 mV, p = .005) and standing (162 ± 179 vs. 486 ± 388 mV, p = .038) positions. Age at diagnosis was the only independent predictor of IS (hazard ratio = 0.873, 95% confidence interval: 0.767-0.992, p = .037). CONCLUSION: IS was a frequent complication in patients with BrS with an S-ICD. Younger age was independently associated with IS. A more thorough screening process might help prevent IS in this population.
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Síndrome de Brugada , Desfibriladores Implantáveis , Adulto , Síndrome de Brugada/diagnóstico , Síndrome de Brugada/terapia , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis/efeitos adversos , Eletrocardiografia , Feminino , Seguimentos , Coração , Humanos , Masculino , Tela Subcutânea , Resultado do TratamentoRESUMO
AIMS: To assess potential benefits of a local activation time (LAT) automatic acquisition protocol using wavefront annotation plus an ECG pattern matching algorithm [automatic (AUT)-arm] during premature ventricular complex (PVC) ablation procedures. METHODS AND RESULTS: Prospective, randomized, controlled, and international multicentre study (NCT03340922). One hundred consecutive patients with indication for PVC ablation were enrolled and randomized to AUT (n = 50) or manual (MAN, n = 50) annotation protocols using the CARTO3 navigation system. The primary endpoint was mapping success. Clinical success was defined as a PVC-burden reduction of ≥80% in the 24-h Holter within 6 months after the procedure. Mean age was 56 ± 14 years, 54% men. The mean baseline PVC burden was 25 ± 13%, and mean left ventricular ejection fraction (LVEF) 55 ± 11%. Baseline characteristics were similar between the groups. The most frequent PVC-site of origin were right ventricular outflow tract (41%), LV (25%), and left ventricular outflow tract (17%), without differences between groups. Radiofrequency (RF) time and number of RF applications were similar for both groups. Mapping and procedure times were significantly shorter in the AUT-arm (25.5 ± 14.3 vs. 32.8 ± 12.6 min, P = 0.009; and 54.8 ± 24.8 vs. 67.4 ± 25.2, P = 0.014, respectively), while more mapping points were acquired [136 (94-222) AUT vs. 79 (52-111) MAN; P < 0.001]. Mapping and clinical success were similar in both groups. There were no procedure-related complications. CONCLUSION: The use of a complete automatic protocol for LAT annotation during PVC ablation procedures allows to achieve similar clinical endpoints with higher procedural efficiency when compared with conventional, manual annotation carried out by expert operators.
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Ablação por Cateter , Complexos Ventriculares Prematuros , Adulto , Idoso , Ablação por Cateter/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Volume Sistólico , Resultado do Tratamento , Função Ventricular Esquerda , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/cirurgiaRESUMO
Background: Chronic diseases have a negative impact on quality of life (QOL) and psychological health. There are limited related data regarding this topic in Brugada syndrome (BrS). We evaluated the effects of the diagnosis of BrS on health-related QOL and psychological status among patients and their relatives. Methods: Patients with BrS and their relatives underwent psychological evaluation at diagnosis (T0), 1 and 2 years after diagnosis (T1 and T2) using questionnaires on mental QOL, anxiety, depression, stress, post-traumatic stress, and resilience resources. Results: Sixty-one patients and 39 relatives were enrolled. Compared with controls, patients showed increased physical QOL (54.1 ± 6.5 vs. 50.1 ± 8.0, p = 0.014), reduced mental QOL (43.2 ± 11.8 vs. 49.6 ± 9.1, p = 0.018) and increased anxiety (9.9 ± 6.6 vs. 6.9 ± 7.7, p = 0.024) at T0; reduced resilience scores (3.69 ± 0.40 vs. 3.96 ± 0.55, p = 0.008) at T1; and reduced resilience (3.69 ± 0.35 vs. 3.96 ± 0.55, p = 0.019) and increased anxiety scores (16.4 ± 12.8 vs. 6.9 ± 7.7, p = 0.006) at T2. Relatives presented higher stress (17.63 ± 3.77 vs. 12.90 ± 6.0, p = 0.02) at T0 and higher anxiety scores at T0 (13.5 ± 7.6 vs. 6.9 ± 7.7, p < 0.001), T1 (12.0 ± 8.7 vs. 6.9 ± 7.7, p = 0.005), and T2 (16.4 ± 12.8 vs. 6.9 ± 7.7, p = 0.006) than controls. Female sex was significantly independently associated with worse mental QOL scores in patients at T0 (odds ratio = 0.10; 95% confidence interval = 0.05-0.94; p = 0.04). Conclusions: The diagnosis of BrS impairs the QOL and psychological status of patients and their relatives. Female sex is independently associated with worse mental QOL in patients at diagnosis.
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Aortic valve stenosis (AS) induces an alteration in hemodynamic conditions that are responsible for coronary microvasculature impairment. Relief of AS by transcatheter aortic valve implantation (TAVI) is expected to improve the coronary artery hemodynamic. We aimed to assess the midterm effects of TAVI in coronary flow reserve (CFR) and myocardial resistance reserve (MRR) by a continuous intracoronary thermodilution technique. At-rest and hyperemic coronary flow was measured by a continuous thermodilution technique in 23 patients with AS and compared with that in 17 matched controls, and repeated 6 ± 3 months after TAVI in 11 of the patients with AS. In patients with AS, absolute coronary flow at rest was significantly greater, and absolute resistance at rest was significantly less, than in controls (p <0.01 for both), causing less CFR and MRR (1.73 ± 0.4 vs 2.85 ± 1.1, p <0.01 and 1.95 ± 0.4 vs 3.22 ± 1.4, p <0.01, respectively). TAVI implantation yielded a significant 35% increase in CFR (p >0.01) and a 39% increase in MRR (p <0.01) driven by absolute coronary flow at rest reduction (p = 0.03). In patients with AS, CFR and MRR determined by continuous thermodilution are significantly impaired. At 6-month follow-up, TAVI improves these indexes and partially relieves the pathophysiologic alterations, leading to a partial restoration of CFR and MRR.
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Estenose da Valva Aórtica , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Substituição da Valva Aórtica Transcateter , Humanos , Circulação Coronária/fisiologia , Estenose da Valva Aórtica/cirurgia , Hemodinâmica , Vasos Coronários/diagnóstico por imagem , Valva Aórtica/cirurgiaRESUMO
BACKGROUND: The aim of this study was to assess the presence of evidence of ventricular mechanical dyssynchrony in patients with isolated left ventricular noncompaction cardiomyopathy (IVNC) and the potential usefulness of cardiac resynchronization therapy (CRT) in those patients. METHODS AND RESULTS: We studied 25 patients consecutively diagnosed with IVNC and a control group of 50 patients with dilated cardiomyopathy of different etiologies. Mechanical dyssynchrony was assessed by echocardiography by the presence of a septal flash, the time from peak septal to posterior wall displacement, and the time from septal to lateral wall peak systolic velocity. Among the patients with IVNC, 9 received CRT and were followed at 12 months. Overall, dyssynchrony parameters were significantly more frequent in IVNC, regardless of QRS duration. All 9 IVNC patients treated with CRT showed a septal flash, and a favorable response was observed in 8/9 patients (89%) regardless of QRS width. CONCLUSIONS: The presence of mechanical dyssynchrony, amenable to correction with CRT, is common in patients with IVNC, independently from QRS width. This might be related to altered electrical endocardial activation associated with abnormal myocardium and could be the justification for the high response rate to CRT observed in these patients.
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Terapia de Ressincronização Cardíaca/métodos , Cardiomiopatia Dilatada/fisiopatologia , Cardiomiopatia Dilatada/terapia , Adulto , Idoso , Fenômenos Biomecânicos/fisiologia , Terapia de Ressincronização Cardíaca/tendências , Cardiomiopatia Dilatada/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND: To predict the outflow tract ventricular arrhythmias (OTVA) site of origin (SOO) before the ablation procedure has important practical implications. The present study sought to prospectively evaluate the accuracy of a clinical and electrocardiographic hybrid algorithm (HA) for the prediction of OTVAs-SOO, and at the same time to develop and to prospectively validate a new score with improved discriminatory capacity. METHODS: In this multicenter study, we prospectively enrolled consecutive patients referred for OTVA ablation (N = 202), and we divided them in a derivation sample and a validation cohort. Surface ECGs during OTVA were analyzed to compare previous published ECG-only criteria and to develop a new score. RESULTS: In the derivation sample (N = 105), the correct prediction rate of HA and ECG-only criteria ranged from 74 to 89%. R-wave amplitude in V3 was the best ECG parameter for discriminating LVOT origin in V3 precordial transition (V3PT) patients, and was incorporated to the novel weighted hybrid score (WHS). WHS correctly classified 99 (94.2%) patients, presenting 90% sensitivity and 96% specificity (AUC 0.97) in the entire population; WHS mantained a 87% sensitivity and 91% specificity (AUC 0.95) in patients with V3PT subgroup. The high discriminatory capacity was confirmed in the validation sample (N = 97): the WHS exhibited an AUC (0.93), and a WHS ≥ 2 allowed a correct prediction of LVOT origin in 87 (90.0%) cases, yielding a sensitivity of 87% and specificity of 90%; moreover, the V3PT subgroup showed an AUC of 0.92, and a punctuation ≥ 2 predicted an LVOT origin with a sensitivity of 94% and specificity of 78%. CONCLUSIONS: The novel hybrid score has proved to accurately anticipate the OTVA's origin, even in those with a V3 precordial transition. A Weighted hybrid score. B Typical examples of the use of the weighted hybrid score. C ROC analysis of WHS and previous ECG criteria for prediction of LVOT origin in the derivation cohort. D ROC analysis of WHS and previous ECG criteria for prediction of LVOT origin in the V3 precordial transition OTVA subgroup.
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BACKGROUND: Catheter ablation is recommended as first-line therapy for patients with symptomatic typical AFl. Although the conventional multi-catheter approach is the standard of care for cavotricuspid isthmus (CTI) ablation, a single-catheter approach was recently described as a feasible alternative. The present study sought to compare safety, efficacy, and efficiency of single vs. multi-catheter approach for atrial flutter (AFl) ablation. METHODS: In this randomized multi-center study, consecutive patients referred for AFl ablation (n = 253) were enrolled and randomized to multiple vs. single-catheter approach for CTI ablation. In the single-catheter arm, PR interval (PRI) on the surface ECG was used to prove CTI block. Procedural and follow-up data were collected and compared between the two arms. RESULTS: 128 and 125 patients were assigned to the single-catheter and to the multi-catheter arms, respectively. In the single-catheter arm, procedure time was significantly shorter (37 ± 25 vs. 48 ± 27 minutes, p = 0.002) and required less fluoroscopy time (430 ± 461 vs. 712 ± 628 seconds, p < 0.001) and less radiofrequency time (428 ± 316 vs. 643 ± 519 seconds, p < 0.001), achieving a higher first-pass CTI block rate (55 (45%) vs. 37 (31%), p = 0.044), compared with the multi-catheter arm. After a median follow-up of 12 months, 11 (4%) patients experienced AFl recurrences (5 (4%) in the single-catheter arm and 6 (5%) in the multi-catheter arm, p = 0.99). No differences were found in arrhythmia-free survival between arms (log-rank = 0.71). CONCLUSIONS: The single-catheter approach for typical AFl ablation is not inferior to the conventional multiple-catheter approach, reducing procedure, fluoroscopy, and radiofrequency time.
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Flutter Atrial , Ablação por Cateter , Humanos , Resultado do Tratamento , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Flutter Atrial/cirurgia , Ablação por Cateter/métodos , CatéteresRESUMO
AIMS: There is insufficient evidence to implant a combined cardiac resynchronization therapy (CRT) device with defibrillation capabilities (CRT-D) in all CRT candidates. The aim of the study was to assess myocardial scar size and its heterogeneity as predictors of sudden cardiac death (SCD) in CRT candidates. METHODS AND RESULTS: A cohort of 78 consecutive patients with dilated cardiomyopathy and class I indication for CRT-D were prospectively enrolled. Before CRT-D implantation, a contrast-enhanced cardiac magnetic resonance (ce-CMR) was performed. The core and border zone (BZ) of the myocardial scar were characterized and quantified with a customized post-processing software. The first appropriate implantable cardioverter defibrillator (ICD) therapy was considered as a surrogate of SCD. During a mean follow-up of 25 months (25-75th percentiles, 15-34), appropriate ICD therapy occurred in 11.5% of patients. In a multivariate Cox proportional hazards regression model for clinical and ce-CMR variables, the scar mass percentage [hazards ratio (HR) per 1% increase 1.1 (1.06-1.15), P < 0.01], the BZ mass [HR per 1 g increase 1.06 (1.04-1.09), P < 0.01], and the BZ percentage of the scar [HR per 1% increase 1.06 (1.02-1.11), P < 0.01], were the only independent predictors of appropriate ICD therapy. Receiver-operating characteristic curve analysis showed that a scar mass <16% and a BZ < 9.5 g had a negative predictive value of 100%. CONCLUSIONS: The presence, size, and heterogeneity of myocardial scar independently predict appropriate ICD therapies in CRT candidates. The ce-CMR-based scar analysis might help identify a subgroup of patients at relatively low risk of SCD.
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Terapia de Ressincronização Cardíaca , Cardiomiopatia Dilatada/terapia , Cicatriz/patologia , Morte Súbita Cardíaca/prevenção & controle , Miocárdio/patologia , Taquicardia Ventricular/terapia , Idoso , Terapia de Ressincronização Cardíaca/efeitos adversos , Terapia de Ressincronização Cardíaca/mortalidade , Dispositivos de Terapia de Ressincronização Cardíaca , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/mortalidade , Cardiomiopatia Dilatada/patologia , Cardiomiopatia Dilatada/fisiopatologia , Distribuição de Qui-Quadrado , Cicatriz/etiologia , Cicatriz/fisiopatologia , Meios de Contraste , Morte Súbita Cardíaca/etiologia , Desfibriladores Implantáveis , Feminino , Fibrose , Gadolínio DTPA , Humanos , Interpretação de Imagem Assistida por Computador , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Prospectivos , Curva ROC , Fatores de Risco , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/mortalidade , Taquicardia Ventricular/patologia , Taquicardia Ventricular/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/terapia , Função Ventricular EsquerdaRESUMO
INTRODUCTION: Echocardiographic optimization of the VV interval may improve CRT response, but it is time-consuming and not routinely performed. The aim of this study was to compare the response to cardiac resynchronization therapy (CRT) when the interventricular pacing (VV) interval was optimized by tissue Doppler imaging (TDI) to CRT response when it was optimized following QRS width criteria. METHODS AND RESULTS: The study included 156 consecutive CRT patients with severe heart failure and left bundle-branch block configuration. Atrioventricular interval was selected according to a pulsed Doppler assessment, and VV optimization was randomly assigned to echocardiography (ECHO group, n = 78) or electrocardiography (ECG group, n = 78). Optimal VV was defined for the ECHO group as producing the best LV intraventricular synchrony according to TDI displacement curves and for the ECG group as resulting in the narrowest QRS measured from the earliest deflection. At 6-month follow-up, percentage of echocardiographic responders (defined as neither death nor heart transplantation and a LV end-systolic volume reduction >10%) was higher in the ECG optimized group (50.0% vs 67.9%; P = 0.023), whereas clinical response (defined as neither death nor heart transplantation and >10% improvement in the 6-minute walking test) was similar in both groups (71.8% vs 73.1%; P = 0.858). CONCLUSIONS: VV optimization based on QRS width obtained a higher percentage of responders in terms of LV reverse remodeling compared to the TDI method.
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Bloqueio de Ramo/terapia , Terapia de Ressincronização Cardíaca , Ecocardiografia Doppler de Pulso , Eletrocardiografia , Insuficiência Cardíaca/terapia , Bloqueio de Ramo/diagnóstico por imagem , Bloqueio de Ramo/fisiopatologia , Distribuição de Qui-Quadrado , Teste de Esforço , Tolerância ao Exercício , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Humanos , Modelos Logísticos , Valor Preditivo dos Testes , Estudos Prospectivos , Recuperação de Função Fisiológica , Espanha , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda , Remodelação Ventricular , CaminhadaRESUMO
BACKGROUND: Best practice for cardiac resynchronization therapy (CRT) device optimization is not established. This study compared Tissue Doppler Imaging (TDI) to study left ventricular (LV) synchrony and left ventricular outflow tract velocity-time integral (LVOT VTI) to assess hemodynamic performance. METHODS: LVOT VTI and LV synchrony were tested in 50 patients at three interventricular (VV) delays (LV preactivation at -30 ms, simultaneous biventricular pacing, and right ventricular preactivation at +30 ms), selecting the highest VTI and the greatest degree of superposition of the displacement curves, respectively, as the optimum VV delay. RESULTS: In 39 patients (81%), both techniques agreed (Kappa = 0.65, p < 0.0001) on the optimum VV delay. LV preactivation (VV - 30) was the interval most frequently chosen. CONCLUSIONS: Both TDI and LVOT VTI are useful CRT programming methods for VV optimization. The best hemodynamic response correlates with the best synchrony. In most patients, the optimum VV interval is LV preactivation.
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Terapia de Ressincronização Cardíaca/métodos , Cardiomiopatia Dilatada/terapia , Ecocardiografia Doppler de Pulso/métodos , Hemodinâmica/fisiologia , Isquemia Miocárdica/terapia , Idoso , Idoso de 80 Anos ou mais , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/fisiopatologia , Ecocardiografia Doppler de Pulso/instrumentação , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/fisiopatologiaRESUMO
BACKGROUND: Pacemapping (PM) is a useful maneuver for aiding premature ventricular complex (PVC) ablation. Its standalone clinical value is still to be defined. OBJECTIVES: The purpose of this study was to analyze the efficacy of a predefined PM protocol for low-burden PVC ablation, regardless of their site of origin (SOO) and the presence of structural heart disease. METHODS: This was a prospective, nonrandomized, multicenter study. The PM protocol was performed when <1 PVC/min was found. The "target area" was delimited by the 3 best matching points >94% correlation, and 3 radiofreqency (RF) applications were delivered. RESULTS: Of 185 patients, 105 (57%) underwent activation mapping, 60 (32%) were PM-guided, and 20 (11%) were canceled due to absence of PVCs. Baseline QRS, PVC burden, and outflow tract origin were independent predictors of PM-guided ablation. A higher proportion of right ventricular outflow tract SOO in the PM group (52% vs 40%; P = .03) was observed. Mean target area was 0.6 ± 0.9 cm2. Mean 10-ms isochronal area in local activation time (LAT)-guided procedures was higher (1.7 ± 2.3 cm2; P <.001). Mean number of PM matching points acquired was 39 ± 21 (range 6-98). Mean mapping and RF times were similar in both groups. However, significantly shorter procedural (53 ± 24 vs 61 ± 26 minutes; P = .04) as well as RF times (111 ± 51 vs 149 ± 149 seconds; P = .05) were needed in the PM group using the proposed protocol. Global clinical success reached 87% for the PM group and 90% (P = .58) the for LAT mapping group. CONCLUSION: When LAT mapping is precluded, application of a PM-guided ablation protocol directed to >94% matching correlation target area is a more efficient alternative with comparable clinical results.
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Mapeamento Potencial de Superfície Corporal/métodos , Ablação por Cateter/métodos , Eletrocardiografia Ambulatorial/métodos , Ventrículos do Coração/fisiopatologia , Volume Sistólico/fisiologia , Complexos Ventriculares Prematuros/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Complexos Ventriculares Prematuros/cirurgiaRESUMO
Coronary flow reserve (CFR) is a well-validated flow-based physiological parameter that has shown value in clinical risk stratification. CFR can be invasively assessed, classically by Doppler and, more recently, by thermodilution with saline boluses (CFRthermo-bolus). Alternatively, continuous thermodilution is a novel operator-independent, highly-reproducible technique to invasively quantify maximum absolute coronary flow (AF). This study aimed to assess the feasibility of this method to quantify resting AF and to determine CFR (CFRThermo-infusion) as compared with CFRthermo-bolus. Sixty-two consecutive patients with suspicion of coronary disease and absence of significant epicardial lesions were prospectively investigated. AF at maximal hyperemia (20 mL/min) and at lower infusion rates (6-8-10-12 mL/min) were systematically measured using a dedicated catheter and a temperature/pressure guidewire. The absence of baseline Pd/Pa decrease at 6 (0.15 ± 0.2%), 8 (0.17 ± 0.18%) and 10 mL/min (0.2 ± 0.12%) demonstrated absence of hyperemia at ≤10 mL/min (all pâ¯=â¯NS). However, at 12 mL/min hyperemia was confirmed by a significant decrease in Pd/Pa (1.3 ± 1.5%, p <0.01) and increase in AF from 10 mL/min to 12 mL/min (31.4 ± 28.1 mL, p <0.05). All curve tracings at 10 mL/min (129/129, 100%) were adequate versus only (7/15, 53%) and (15/18, 17%) at 6 mL/min, and 8 mL/min, respectively, and this infusion-rate was considered to determine resting-AF. CFRThermo-infusion was determined as the ratio of hyperemic-AF (20 mL/min) by resting-AF (10 mL/min). Mean CFRThermo-infusion was 2.56 ± 0.9 and CFRthermo-bolus 2.49 ± 1. Both parameters showed a good correlation (râ¯=â¯0.76; p <0.001) and intraclass agreement (ICCâ¯=â¯0.76; p <0.001).The continuous thermodilution method enables to quantify resting-AF providing a novel clinical tool to determine CRF. CFRThermo-infusion shows a good correlation with CFRthermo-bolus..
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Circulação Coronária , Vasos Coronários/fisiopatologia , Hiperemia/fisiopatologia , Microcirculação , Microvasos , Termodiluição/métodos , Idoso , Cateterismo Cardíaco , Angiografia Coronária , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Reprodutibilidade dos Testes , Solução SalinaRESUMO
BACKGROUND: Frequent premature ventricular complexes (PVCs) are common after a myocardial infarction (MI), but data on PVC ablation in this population are limited. OBJECTIVE: The purpose of this study was to analyze data on PVC ablation in post-MI patients. METHODS: Three hundred thirty-two patients with frequent PVCs and left ventricular (LV) dysfunction were prospectively studied. Data from 67 patients (20%; age 63 ± 10 years; 65 men [93%]) with previous MI were compared with the remaining 265 patients. RESULTS: PVCs in post-MI patients originate predominantly from the LV (92% LV vs 6% right ventricle [RV]; P <.001). The most frequent sites of origin (SOO) were MI scar in 23 patients (34%) and left ventricular outflow tract (LVOT) in 22 patients (33%). A papillary muscle origin was more frequent in post-MI patients (16% vs 4%; P = .001), whereas an RV outflow tract origin was less frequent (1% vs 33%; P <.001) compared to patients without MI. In post-MI patients, PVC burden decreased from 29% ± 12% at baseline to 4.6% ± 7% (P <.001); left ventricular ejection fraction (LVEF) improved from 33.6% ± 8% to 42% ± 10% (P <.001); and New York Heart Association functional class improved from 2.1 ± 0.7 to 1.4 ± 0.5 points (P <.001) at 12 months. Compared with the remaining 265 patients, there were no differences in acute ablation success (85% vs 85%; P = .45), complication rate (6% vs 6%; P = .41), or absolute improvement in LVEF (8.8 ± 10 vs 9.9 ± 11 absolute points; P = .38). CONCLUSION: PVC ablation significantly improves cardiac function and functional status in post-MI patients. PVCs predominantly originate from MI scar and LVOT. A papillary muscle SOO was found to be strongly associated with previous MI.
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Ablação por Cateter , Sistema de Condução Cardíaco/fisiopatologia , Ventrículos do Coração/fisiopatologia , Infarto do Miocárdio/complicações , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Complexos Ventriculares Prematuros/diagnóstico , Ecocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Complexos Ventriculares Prematuros/etiologia , Complexos Ventriculares Prematuros/fisiopatologiaRESUMO
BACKGROUND: Fractional flow reserve (FFR) is the "gold standard" for assessing the physiological significance of coronary disease. In the last decade, several alternative adenosine-free indexes have been proposed in order to facilitate the dissemination of the functional evaluation of coronary stenosis. Our aim was to investigate whether radiographic contrast plus intracoronary nitroglycerin (cFFR-NTG) can predict functional assessment of coronary stenosis offering superior diagnostic agreement with FFR compared to non-hyperemic indexes and contrast mediated FFR (cFFR). METHODS: Three hundred twenty-nine lesions evaluated with pressure wire in 266 patients were prospectively included in this multicenter study. RESULTS: The ROC curves for cFFR-NTG using an FFR≤0.80 showed a higher accuracy in predicting FFR (AUC=0.97) than resting Pd/Pa (AUC=0.90, P<0.01) and cFFR (AUC=0.93.5, P<0.01). A significant (P<0.01) strong correlation was found between FFR and the four analyzed indexes: Pd/Pa (r=0.78); iFR/RFR (r=0.73); cFFR(r=0.89) and cFFR-NTG (r=0.93). cFFR-NTG showed the closest agreement at Bland-Altman analysis. The cFFR-NTG cut off value >0.84 showed the highest negative predictive value (88%), specificity (91%), sensitivity (94%) and accuracy (92%) of the studied indexes. CONCLUSIONS: Submaximal hyperemic adenosine-free indexes are an efficient alternative to adenosine for the physiological assessment of epicardial coronary disease. The most accurate index in predicting the functional significance of coronary stenosis using FFR as reference was cFFR-NTG.
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Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Estenose Coronária/diagnóstico , Glicerol , Humanos , Estudos ProspectivosRESUMO
According to clinical studies, around one third of patients with atrial fibrillation (AF) will suffer a stroke during their lifetime. Between 70 and 90% of these strokes are caused by thrombus formed in the left atrial appendage. In patients with contraindications to oral anticoagulants, a left atrial appendage occluder (LAAO) is often implanted to prevent blood flow entering in the LAA. A limited range of LAAO devices is available, with different designs and sizes. Together with the heterogeneity of LAA morphology, these factors make LAAO success dependent on clinician's experience. A sub-optimal LAAO implantation can generate thrombi outside the device, eventually leading to stroke if not treated. The aim of this study was to develop clinician-friendly tools based on biophysical models to optimize LAAO device therapies. A web-based 3D interactive virtual implantation platform, so-called VIDAA, was created to select the most appropriate LAAO configurations (type of device, size, landing zone) for a given patient-specific LAA morphology. An initial LAAO configuration is proposed in VIDAA, automatically computed from LAA shape features (centreline, diameters). The most promising LAAO settings and LAA geometries were exported from VIDAA to build volumetric meshes and run Computational Fluid Dynamics (CFD) simulations to assess blood flow patterns after implantation. Risk of thrombus formation was estimated from the simulated hemodynamics with an index combining information from blood flow velocity and complexity. The combination of the VIDAA platform with in silico indices allowed to identify the LAAO configurations associated to a lower risk of thrombus formation; device positioning was key to the creation of regions with turbulent flows after implantation. Our results demonstrate the potential for optimizing LAAO therapy settings during pre-implant planning based on modeling tools and contribute to reduce the risk of thrombus formation after treatment.
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The left atrial appendage (LAA) is a complex and heterogeneous protruding structure of the left atrium (LA). In atrial fibrillation patients, it is the location where 90% of the thrombi are formed. However, the role of the LAA in thrombus formation is not fully known yet. The main goal of this work is to perform a sensitivity analysis to identify the most relevant LA and LAA morphological parameters in atrial blood flow dynamics. Simulations were run on synthetic ellipsoidal left atria models where different parameters were individually studied: pulmonary veins and mitral valve dimensions; LAA shape; and LA volume. Our computational analysis confirmed the relation between large LAA ostia, low blood flow velocities and thrombus formation. Additionally, we found that pulmonary vein configuration exerted a critical influence on LAA blood flow patterns. These findings contribute to a better understanding of the LAA and to support clinical decisions for atrial fibrillation patients.
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INTRODUCTION AND OBJECTIVES: There is extensive controversy exists on whether cardiac resynchronization therapy corrects electrical or mechanical asynchrony. The aim of this study was to determine if there is a correlation between electrical and mechanical sequences and if myocardial scar has any relevant impact. METHODS: Six patients with normal left ventricular function and 12 patients with left ventricular dysfunction and left bundle branch block, treated with cardiac resynchronization therapy, were studied. Real-time three-dimensional echocardiography and electroanatomical mapping were performed in all patients and, where applicable, before and after therapy. Magnetic resonance was performed for evaluation of myocardial scar. Images were postprocessed and mechanical and electrical activation sequences were defined and time differences between the first and last ventricular segment to be activated were determined. Response to therapy was defined as a reduction in left ventricular end-systolic volume ≥ 15% after 12 months of follow-up. RESULTS: Good correlation between electrical and mechanical timings was found in patients with normal left ventricular function (r(2) = 0.88; P = .005) but not in those with left ventricular dysfunction (r(2) = 0.02; P = not significant). After therapy, both timings and sequences were modified and improved, except in those with myocardial scar. CONCLUSIONS: Despite a close electromechanical relationship in normal left ventricular function, there is no significant correlation in patients with dysfunction. Although resynchronization therapy improves this correlation, the changes in electrical activation may not yield similar changes in left ventricular mechanics particularly depending on the underlying myocardial substrate.
Assuntos
Terapia de Ressincronização Cardíaca , Idoso , Bloqueio de Ramo/patologia , Bloqueio de Ramo/fisiopatologia , Bloqueio de Ramo/terapia , Estudos de Casos e Controles , Ecocardiografia Tridimensional , Feminino , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/terapia , Função Ventricular Esquerda/fisiologiaRESUMO
In cardiac resynchronization therapy (CRT), specific changes in motion/deformation happen with left-bundle-branch-block (LBBB) and following treatment. However, they remain sub-optimally studied. We propose a two-fold improvement of their characterization. This includes controlling them through an experimental model and using more suitable quantification techniques. We used a swine model of acute LBBB and CRT with/without chronic infarct (pure-LBBB: N = 11; LBBB + left-anterior-descending infarct: N = 11). Myocardial displacement, velocity and strain were extracted from short-axis echocardiographic sequences using 2D speckle-tracking. The data was transformed to a single spatiotemporal system of coordinates to perform subject comparisons and quantify pattern changes at similar locations and instants. Pure-LBBB animals showed a specific intra-ventricular dyssynchrony pattern with LBBB (11/11 animals), and the recovery towards a normal pattern with CRT (10/11 animals). Pattern variability was low within the pure-LBBB population, as quantified by our method. This was not correctly assessed by more conventional measurements. Infarct presence affected the pattern distribution and CRT efficiency (improvements in 6/11 animals). Pattern changes correlated with global cardiac function (global circumferential strain) changes in all the animals (corrected: (pLBBBvsBaseline) < 0.001, (pCRTvsBaseline) = NS; non-corrected: (pLBBBvsBaseline) = NS, (pCRTvsBaseline) = 0.028). Our LBBB/CRT experimental model allowed controlling specific factors responsible for changes in mechanical dyssynchrony and therapy. We illustrated the importance of our quantification method to study these changes and their variability. Our findings confirm the importance of myocardial viability and of specific LBBB-related mechanical dyssynchrony patterns.
Assuntos
Bloqueio de Ramo/fisiopatologia , Bloqueio de Ramo/terapia , Terapia de Ressincronização Cardíaca/métodos , Infarto do Miocárdio/fisiopatologia , Doença Aguda , Animais , Doença Crônica , Modelos Animais de Doenças , Ecocardiografia , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , SuínosRESUMO
Animal models that mimic human electrical and mechanical dyssynchrony often associated with chronic heart failure would provide an essential tool to investigate factors influencing response to cardiac resynchronization therapy. A standardized closed-chest porcine model of left bundle branch block (LBBB) was developed using 16 pigs. Radiofrequency applications were performed to induce LBBB, which was confirmed by QRS widening, a surface electrocardiogram pattern concordant with LBBB, and a prolonged activation time from endocardial. Echocardiography confirmed abnormal motion of the septum, which was not present at the baseline echocardiogram. High susceptibility of pigs to ventricular fibrillation during the endocardial ablation was overcome by applying high-rate pacing during radiofrequency applications. This is the first study to devise a closed-chest porcine model of LBBB that closely reproduces abnormalities found in patients with electrical and mechanical cardiac dyssynchrony, and provides a useful tool to investigate the basic mechanisms underlying cardiac resynchronization therapy benefits in heart failure.