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1.
Sci Rep ; 14(1): 12140, 2024 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802515

RESUMO

This study leverages mobile data for 5.4 million users to unveil the complex dynamics of daily mobility and longer-term relocations in and from Santiago, Chile, during the COVID-19 pandemic, focusing on socioeconomic differentials. We estimated a relative increase in daily mobility, in 2020, for lower-income compared to higher-income regions. In contrast, longer-term relocation rose primarily among higher-income groups. These shifts indicate nuanced responses to the pandemic across socioeconomic classes. Compared to 2017, economic factors in 2020 had a stronger influence on the decision to relocate and the selection of destinations, suggesting transformations in mobility behaviors. Contrary to previously held beliefs, there was no evidence supporting a preference for rural over urban destinations, despite the surge in emigration from Santiago during the pandemic. This study enhances our understanding of how varying socioeconomic conditions interact with mobility decisions during crises and provides insights for policymakers aiming to enact fair and evidence-based measures in rapidly changing circumstances.


Assuntos
COVID-19 , Pandemias , COVID-19/epidemiologia , Humanos , Chile/epidemiologia , Fatores Socioeconômicos , SARS-CoV-2/isolamento & purificação , Emigração e Imigração , População Rural , Classe Social
2.
J Stroke Cerebrovasc Dis ; 32(6): 107138, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37087772

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the impact of COVID-19 pandemic public health restrictions on our drip and ship mechanical thrombectomy program in Santiago Chile. MATERIALS AND METHODS: This was a retrospective analysis of a prospectively collected database comparing two cohorts, one during a two-year period before COVID-19 and the second during the two years of the pandemic at our metropolitan stroke program. RESULTS: A total of 100 patients were included in the pre COVID-19 cohort (cohort 1) and 121 in the COVID-19 cohort (cohort 2). There was a significant difference between cohorts, with older patients, different occlusion sites and higher door to arterial puncture time during the COVID-19 period. A non-significant trend for worse 90-day outcomes and higher mortality was present in cohort 2. There were no statistical differences in safety treatment parameters. CONCLUSIONS: COVID-19 pandemic has had a measurable impact on our mechanical thrombectomy program. Results showed similarities to other reported Latin American series, where less robust health systems could adapt less efficiently compared to developed countries. After two years of public health restrictions, there were changes in the treatment population characteristics, delay in some internal management metrics and a non-significant trend to worse 90-day outcomes and higher mortality.


Assuntos
Isquemia Encefálica , COVID-19 , Acidente Vascular Cerebral , Humanos , Síndrome de COVID-19 Pós-Aguda , Isquemia Encefálica/terapia , Trombectomia/efeitos adversos , Trombectomia/métodos , Estudos Retrospectivos , COVID-19/epidemiologia , Pandemias , Saúde Pública , Resultado do Tratamento , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/epidemiologia
3.
J Clin Med ; 12(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36675339

RESUMO

Background: Determining the mechanism of supraventricular tachycardias with prolongedP ventriculoatrial (VA) intervals is sometimes a challenge. Our objective is to analyse the determinants, time course and diagnostic accuracy (atypical atrioventricular nodal reentrant tachycardias [AVNRT] versus orthodromic reentrant tachycardias through an accessory pathway [ORT]) of spontaneous VA intervals variation in patients with narrow QRS tachycardias and prolonged VA. Methods: A total of 156 induced tachycardias were studied (44 with atypical AVNRT and 112 with ORT). Two sets of 10 measurements were performed for each patient­after tachycardia induction and one minute later. VA and VV intervals were determined. Results: The difference between the longest and the shortest VA interval (Dif-VA) correlates significantly with the diagnosis of atypical AVNRT (C coefficient = 0.95 and 0.85 after induction and at one minute, respectively; p < 0.001). A Dif-VA ≥ 15 ms presents a sensitivity and specificity for atypical AVNRT of 50% and 99%, respectively after induction, and of 27% and 100% one minute later. We found a robust and significant correlation between the fluctuations of VV and VA intervals in atypical AVNRTs (Coefficient Rho: 0.56 and 0.76, after induction and at one minute, respectively; p < 0.001 for both) but not in ORTs. Conclusions: The analysis of VA interval variability after induction and one minute later correctly discriminates atypical AVNRT from ORT in almost all cases.

4.
Sci Data ; 10(1): 6, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596790

RESUMO

Fighting the COVID-19 pandemic, most countries have implemented non-pharmaceutical interventions like wearing masks, physical distancing, lockdown, and travel restrictions. Because of their economic and logistical effects, tracking mobility changes during quarantines is crucial in assessing their efficacy and predicting the virus spread. Unlike many other heavily affected countries, Chile implemented quarantines at a more localized level, shutting down small administrative zones, rather than the whole country or large regions. Given the non-obvious effects of these localized quarantines, tracking mobility becomes even more critical in Chile. To assess the impact on human mobility of the localized quarantines, we analyze a mobile phone dataset made available by Telefónica Chile, which comprises 31 billion eXtended Detail Records and 5.4 million users covering the period February 26th to September 20th, 2020. From these records, we derive three epidemiologically relevant metrics describing the mobility within and between comunas. The datasets made available may be useful to understand the effect of localized quarantines in containing the COVID-19 pandemic.


Assuntos
COVID-19 , Quarentena , Humanos , Chile , Controle de Doenças Transmissíveis , COVID-19/epidemiologia , Pandemias
5.
EPJ Data Sci ; 10(1): 29, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34094810

RESUMO

Inferring mobile phone users' home location, i.e., assigning a location in space to a user based on data generated by the mobile phone network, is a central task in leveraging mobile phone data to study social and urban phenomena. Despite its widespread use, home detection relies on assumptions that are difficult to check without ground truth, i.e., where the individual who owns the device resides. In this paper, we present a dataset that comprises the mobile phone activity of sixty-five participants for whom the geographical coordinates of their residence location are known. The mobile phone activity refers to Call Detail Records (CDRs), eXtended Detail Records (XDRs), and Control Plane Records (CPRs), which vary in their temporal granularity and differ in the data generation mechanism. We provide an unprecedented evaluation of the accuracy of home detection algorithms and quantify the amount of data needed for each stream to carry out successful home detection for each stream. Our work is useful for researchers and practitioners to minimize data requests and maximize the accuracy of the home antenna location. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1140/epjds/s13688-021-00284-9.

6.
Interv Neuroradiol ; 27(1): 114-118, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32873104

RESUMO

BACKGROUND: Mechanical Thrombectomy (MT) is the standard of care for treatment of large vessel occlusion stroke. Until the beginning of 2020 MT was not funded nor widely implemented at the public healthcare level in Chile. OBJECTIVE: To describe the results of a pilot program created to provide access to public MT in Santiago - Chile. METHODS: Analysis from a prospectively collected database of MT cases performed between September 2017 and September 2019 in one center. A stroke network was developed with a single MT capable stroke center and five primary stroke centers. The primary efficacy endpoint was the rate of functional independence (mRS 0-2) at 90 days. Successful reperfusion was defined as 2 b-3 according to the thrombolysis in cerebral infarction scale. Safety outcomes include the rates of symptomatic intracranial hemorrhage and 90-day mortality. RESULTS: A total of 100 patients were treated over the study period. Their mean age was 62.8 ± 11.8 years and median baseline National Institute of Health Stroke Scale (NIHSS) measurement was 17. Seventy-seven percent of the patients received intra venous thrombolysis. Successful reperfusion was achieved in 95% of the cases. NIHSS at 24 hours showed a median drop of 7 points from baseline (p < 0.00001) and 50% of the follow-up patients were functionally independent at 90 days. Symptomatic Intracerebral hemorrhage occurred in 5% of the patients and 90-day all case mortality was 11%. CONCLUSIONS: We demonstrated the feasibility of a publicly funded MT program in Chile, with similar results as other international randomized control trials.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Idoso , Chile , Atenção à Saúde , Humanos , América Latina , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos , Acidente Vascular Cerebral/terapia , Trombectomia , Resultado do Tratamento
7.
J Interv Card Electrophysiol ; 56(3): 349-357, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31529171

RESUMO

PURPOSE: Antitachycardia pacing (ATP) terminates the majority (but not all) of slow ventricular tachycardias (S-VT) with a cycle length (CL) > 320 ms. Usually, several ATP therapies are programmed in the S-VT zone. Our objective is to analyse the ATP effectiveness, comparing the first ATP attempt (ATP-1) to the second (ATP-2) and third (ATP-3) attempts. METHODS: We studied 556 S-VT (CL = 354 ± 18). ATP programming was standardized and included three bursts of 15 pulses at 91% of VT CL. RESULTS: ATP effectiveness declined from ATP-1 (436/556: 78%) compared to ATP-2 (24/103: 23%) and ATP-3 (10/79: 13%) (p < 0.01) for all comparisons. The percentage of variation of RR intervals (P-RR, %) was higher prior to effective ATP-1 (2.73 ± 1.45 vs. 1.23 ± 0.9; p < 0.001). After an ineffective ATP-1, the P-RR decreased dramatically, with no differences between episodes terminated or not at ATP-2 (0.6 ± 0.14 vs. 0.44 ± 0.16; p = 0.6) or ATP-3 (0.54 ± 0.15 vs. 0.52 ± 0.14; p = 0.7). The post-pacing interval-CL difference (PPI-TCLd) after an unsuccessful ATP-1 was shorter in episodes terminating at ATP-2 or ATP-3 (180 ± 24 vs. 211 ± 15 ms; p < 0.001). Several independent predictors of ATP efficacy were found, as follows: (a) ATP-1: P-RR, % (OR = 7.3; p < 0.001), beta-blockers (OR = 4.1; p < 0.001) and QRS ≥ 120 ms (OR = 0.3; p < 0.001); (b) ATP-2: PPI-TCLd, ms (OR = 0.94; p = 0.001) and QRS ≥ 120 ms (OR = 0.6; p = 0.04); (c) ATP-3: PPI-TCLd, ms (OR = 0.93; p = 0.009). CONCLUSIONS: The effectiveness of ATP is mainly due to ATP-1. The regularization of RR intervals after ineffective ATP-1 underlies the lower efficacy of successive attempts. Shorter PPI-TCLd is associated with higher effectiveness of ATP-2 and ATP-3. Since a duration of QRS ≥ 120 ms predicts a longer PPI-TCLd, patients with wide QRS complexes have less effective ATP-2 and APT-3.


Assuntos
Estimulação Cardíaca Artificial/métodos , Taquicardia Ventricular/terapia , Idoso , Eletrocardiografia , Feminino , Humanos , Masculino , Volume Sistólico , Taquicardia Ventricular/fisiopatologia
8.
J Interv Card Electrophysiol ; 52(1): 69-76, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29557531

RESUMO

INTRODUCTION: Among implantable cardioverter-defibrillator (ICD) patients, a substantial proportion of syncopes are due to fast ventricular tachycardias (FVTs). In the experimental models of ventricular tachycardias, the arterial vasoconstriction plays an important role in recovering the arterial pressure. Since beta-blockers increase vascular resistance, we hypothesized that beta-blockers could reduce the occurrence of syncope due to FVTs. Our objective was to determine the relationship between the beta-blocker therapy and the incidence of syncope in FVT (cycle length [CL] 250-320 ms) occurring in ICD patients. Slow VTs were excluded because of the lack of symptoms and VF episodes because of the small number. METHODS AND RESULTS: In this multicenter study, 226 patients (LVEF 31 ± 10%) with single-chamber ICDs were followed. FVT programming was standardized, including antitachycardia pacing (ATP) as initial therapy. Symptoms were correlated with ICD-stored episode data of FVTs. The beta-blocker therapy was determined at each FVT presentation. We analyzed 289 FVTs (CL 291 ± 21 ms; 77% under beta-blockers; median of the duration:8 s) occurring consecutively in 52 ICD patients. The frequency of FVT-related syncope was 22 (7.6%). Beta-blockers were associated with a lower heart rate preceding FVT (85 ± 22 vs. 94 ± 23 bpm; p = 0.009), a higher ATP effectiveness (86 vs. 57%; p < 0.001), a lower duration of episodes (8 [2] vs. 10 [14] s; p < 0.001), and a lower incidence of FVT-related syncope (4.5 vs. 18%; p < 0.001). By logistic regression, a FVT > 8 s (OR = 21; p = 0.003) and the beta-blocker therapy (OR = 0.3; p = 0.012) were found as independent predictors of syncope. CONCLUSION: Among ICD patients with left ventricular dysfunction, beta-blockers are associated with a lower incidence of FVT-related syncope.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Desfibriladores Implantáveis/estatística & dados numéricos , Síncope/prevenção & controle , Taquicardia Ventricular/terapia , Disfunção Ventricular Esquerda/tratamento farmacológico , Idoso , Estudos de Coortes , Relação Dose-Resposta a Droga , Eletrocardiografia/métodos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Taxa de Sobrevida , Síncope/tratamento farmacológico , Taquicardia Ventricular/diagnóstico por imagem , Taquicardia Ventricular/mortalidade , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico por imagem
9.
Europace ; 20(10): 1638-1646, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29300867

RESUMO

Aims: Tachycardia mediated by septal accessory pathways (AP) and atypical atrioventricular nodal re-entry (AVNRT) require careful electrophysiologic evaluation for differential diagnosis. We aim to describe the differential behaviour of local ventriculo-atrial (VA) intervals which predicts the tachycardia mechanism. Methods and results: The local VA intervals at the para-Hisian septum were measured under three different situations: (i) tachycardia; (ii) sustained entrainment from the right ventricular apex (RVA); and (iii) continuous pacing from the RVA during sinus rhythm. Differences were computed as follows: Δ-VAentr = VA during entrainment - VA during tachycardia; and Δ-VApac = VA while pacing during sinus rhythm - VA during tachycardia. In contrast to AVNRT, we hypothesized that an invariable retrograde conduction through the septal AP will keep the result of the subtractions close to 0 ms in cases of ortodromic atrioventricular re-entrant tachycardia (AVRT). We analysed 55 atypical AVNRT (45% posterior type) and 82 AVRT (10 anteroseptal, 18 para-Hisian, 12 mid-septal, and 42 posteroseptal). Δ-VAentr was longer for AVNRT (98.5 ± 40.3 ms) compared with septal AP (-5.7 ± 19.3 ms; P < 0.001). A value of 50 ms showed 98.7% sensitivity and 92% specificity (AUC 0.99; 95% CI 0.98-1). According to physiological criteria, a negative Δ-VAentr remains unobserved in the case of AVNRT (positive predictive value 100% for septal AP). Δ-VApac was also longer for AVNRT (66.5 ± 14.6 ms) compared with septal AP (-9.7 ± 3.3 ms; P < 0.001). A value of 50 ms showed 100% sensitivity and 74% specificity (AUC 0.86; 95% CI 0.76-0.93). Conclusions: Delta of the local VA intervals enables distinction between atypical AVNRT and AVRT mediated by septal AP.


Assuntos
Feixe Acessório Atrioventricular/fisiopatologia , Técnicas Eletrofisiológicas Cardíacas/métodos , Taquicardia por Reentrada no Nó Atrioventricular/fisiopatologia , Feixe Acessório Atrioventricular/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Taquicardia por Reentrada no Nó Atrioventricular/diagnóstico
10.
Eur Heart J Acute Cardiovasc Care ; 7(5): 484-489, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28879778

RESUMO

Extracorporeal membrane oxygenation systems have undergone rapid technological improvements and are now feasible options for medium-term support of severe cardiac or pulmonary failure. We report five cases of electrical storm that was rescued by the insertion of peripheral veno-arterial extracorporeal membrane oxygenation systems. This device could help to restore systemic circulation as well as permitting organ perfusion in patients with cardiogenic shock in relation to electrical storm thus achieving greater electrical stability. Also, in some cases extracorporeal membrane oxygenation support could facilitate electrophysiology study.


Assuntos
Mapeamento Potencial de Superfície Corporal/métodos , Cardiomiopatia Dilatada/cirurgia , Ablação por Cateter/métodos , Sistema de Condução Cardíaco/fisiopatologia , Taquicardia Ventricular/terapia , Idoso , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/fisiopatologia , Sistema de Condução Cardíaco/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologia , Resultado do Tratamento
11.
Europace ; 20(8): 1334-1342, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036312

RESUMO

Aims: Radiofrequency ablation (RFA) of septal accessory pathways (APs) is associated with a significant rate of first procedure failures and complications. Cryoablation is an alternative energy source but there are no studies comparing both ablation techniques. We aimed to systematically review the literature and compare the efficacy and safety of cryoablation vs. RFA of septal APs. Methods and results: We conducted two separate meta-analysis of cryoablation and RFA of septal APs and calculated the global estimates of the efficacy and safety. Sixty-four articles were included: 38 articles reporting RFA and 27 articles reporting cryoablation procedures. Additionally, we included the previously non-published cryoablation registry of septal APs performed at our institution. Overall, 4244 septal APs constitute our study population, 3495 in the RFA cohort and 749 in the cryoablation cohort. Acute procedural success rate of cryoablation was 86.0% (95% CI 81.6-89.4%) and RFA 89.0% (95% CI 86.8-91.0%). Recurrence rate of cryoablation was 18.1% (95% CI 14.8-21.8%) and RFA 9.9% (95% CI 8.2-12.0%). Long-term success rate after multiple ablation procedures of cryoablation was 75.9% (95% CI 68.2-82.3%) and RFA 88.4% (95% CI 84.7-91.3%). There were no reported cases of persistent atrioventricular block (AVB) with cryoablation and 2.7% (95% CI 2.2-3.4%) with RFA. Conclusion: Studies of RFA for treatment of septal APs report higher efficacy rates than do studies using cryoablation, but a significantly higher rate of AVB.


Assuntos
Feixe Acessório Atrioventricular/cirurgia , Ablação por Cateter , Criocirurgia , Feixe Acessório Atrioventricular/fisiopatologia , Potenciais de Ação , Adolescente , Adulto , Idoso , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Bloqueio Atrioventricular/etiologia , Bloqueio Atrioventricular/fisiopatologia , Ablação por Cateter/efeitos adversos , Criança , Pré-Escolar , Criocirurgia/efeitos adversos , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
12.
Am J Cardiol ; 118(10): 1503-1510, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27634031

RESUMO

Nonsustained ventricular tachycardias (NSVTs) are frequently observed in patients with left ventricular (LV) dysfunction. The prognostic implications of such NSVTs are conflicting. Our objective was to determine the relation between the burden of NSVT occurring early (within the first 6 months after ICD implant) and prognosis among ICD patients with LV dysfunction. We followed 416 ICD patients (age: 65 ± 11 years; LV ejection fraction: 30 ± 8; ischemic origin: 62%; primary prevention: 63%) with LV dysfunction for 41 ± 27 months. ICD programming was standardized. NSVT was defined as any VT of ≥5 beats at ≥150 beats/min which did not meet the detection criteria occurring within the first 6 months after ICD implant. A total of 250 patients (60%) presented at least one NSVT (median = 2; interquartile range 0 to 7). We classified the patients into 3 groups according to the number of NSVTs: no NSVT (n = 166); 1 to 5 NSVTs (n = 130); and >5 NSVTs (n = 120). The incidence of cardiac mortality (7.2% vs 17.7% vs 31.7%; p = 0.003), hospitalizations for heart failure (10.6% vs 24.4% vs 44.7%; p <0.001), and appropriate shock (15.7% vs 24.8% vs 43.8%; p <0.001) increased significantly with the number of NSVTs. By multivariate analysis, >5 NSVTs were found to be an independent predictor of cardiac mortality (hazard ratio [HR] 1.75; p = 0.03), hospitalization due to heart failure (HR 1.72; p = 0.001), and appropriate shock (HR 1.89; p <0.001) but not of inappropriate therapy (HR 0.9; p = 0.6). In conclusion, among ICD patients with LV dysfunction, NSVT episodes occurring in the first 6 months after implant are independently associated with a poor prognosis. Subjects with >5 NSVTs are at the highest risk.


Assuntos
Desfibriladores Implantáveis , Insuficiência Cardíaca/epidemiologia , Medição de Risco , Taquicardia Ventricular/terapia , Disfunção Ventricular Esquerda/complicações , Idoso , Eletrocardiografia , Feminino , Seguimentos , Insuficiência Cardíaca/etiologia , Frequência Cardíaca , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Estudos Retrospectivos , Espanha/epidemiologia , Taxa de Sobrevida/tendências , Taquicardia Ventricular/complicações , Taquicardia Ventricular/fisiopatologia , Fatores de Tempo , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia
13.
Circ Arrhythm Electrophysiol ; 8(5): 1201-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26334054

RESUMO

BACKGROUND: Differential diagnosis between tachycardia mediated by septal accessory pathways (AP) and atypical atrioventricular nodal reentry can be challenging. We hypothesized that an immediate versus delayed pace-related advancement of the atrial electrogram, once the local septal parahisian ventricular electrogram (SVE) has been advanced, may help in this diagnosis. METHODS AND RESULTS: We focused on differential timing between SVE and atrial signals at the initiation of continuous right ventricular apical pacing during tachycardia. SVE advancement preceding atrial reset was defined as SVE advanced by the paced wave fronts while atrial signal continued at the tachycardia cycle. We analyzed 51 atypical atrioventricular nodal reentry (45% posterior type) and 80 AP tachycardias (anteroseptal [10], parahisian [18], midseptal [12], and posteroseptal [40]). SVE advancement preceding atrial reset was observed in 98% of atrioventricular nodal reentries during 4±1.1 cycles; this phenomena was observed in 6 (8%) of the atrioventricular reentrant tachycardia mediated by septal AP (P<0.001; sensitivity 98%; specificity 93%; positive predictive value 90%; negative predictive value 99%) and lasted 1 single cycle (P<0.001). Right posteroseptal AP tachycardias were distinctly characterized by atrial reset preceding SVE advancement (with ventricular fusion; specificity 100%; positive predictive value 100%). In 11 cases, it was impossible to achieve sustain entrainment. In all of them, the differential responses at the entrainment attempt allowed for appropriate diagnosis. CONCLUSIONS: The differential response of the SVE and the atrial electrogram at the initiation of continuous right ventricular apical pacing during tachycardia effectively distinguishes between atypical atrioventricular nodal reentry and atrioventricular reentrant tachycardia mediated by septal APs.


Assuntos
Feixe Acessório Atrioventricular/fisiopatologia , Técnicas Eletrofisiológicas Cardíacas , Sistema de Condução Cardíaco/fisiopatologia , Taquicardia por Reentrada no Nó Atrioventricular/diagnóstico , Taquicardia Reciprocante/diagnóstico , Estimulação Cardíaca Artificial , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Taquicardia por Reentrada no Nó Atrioventricular/fisiopatologia , Taquicardia Reciprocante/fisiopatologia
14.
J Interv Card Electrophysiol ; 44(2): 187-95, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26306456

RESUMO

PURPOSE: To determine whether monomorphic ventricular tachycardias (VTs) have different characteristics and/or responses to antitachycardia pacing (ATP) with respect to the indication-primary prevention (PP) versus secondary prevention (SP)-among ICD patients with left ventricular dysfunction. METHODS: We prospectively studied 551 VT (cycle length [CL] 329 ± 35 ms; PP 34%) occurring in 67 ICD patients with left ventricular dysfunction (LVEF 35 ± 8%). ICD programming was standardized, including ATP for slow (CL 400-321 ms) and fast VT (CL 250-320 ms). We analyzed the following aspects: CL, percentage of variability of the 12 RR intervals prior to ATP (P-RR)-which was calculated by dividing the mean difference between each R-R interval with the next one by the CL × 100-and type of termination: immediate (VT ceased immediately upon ATP completion) or delayed (VT persisted after ATP). RESULTS: ATP was successful in 86% of VTs. VTs occurring in SP patients had a lower P-RR, median (IQR) 2.7% (1.2-3.7) versus 1.9% (0.9-3.2); p = 0.002; they terminated immediately after ATP less frequently (27% versus 12%; p < 0.001), and although they were more frequently slow (51% versus 67%; p = 0.01), ATP was less effective in them, 92 versus 80% (p = 0.02). CONCLUSIONS: VTs occurring in SP patients are slower, more stable, and they terminate less frequently at ATP. Therefore, compared with PP, SP patients seem to have fewer self-terminating VTs.


Assuntos
Desfibriladores Implantáveis/estatística & dados numéricos , Técnicas Eletrofisiológicas Cardíacas/estatística & dados numéricos , Prevenção Primária/estatística & dados numéricos , Prevenção Secundária/estatística & dados numéricos , Taquicardia Ventricular/epidemiologia , Taquicardia Ventricular/prevenção & controle , Idoso , Estimulação Cardíaca Artificial/métodos , Estimulação Cardíaca Artificial/estatística & dados numéricos , Feminino , Humanos , Incidência , Masculino , Recidiva , Fatores de Risco , Espanha/epidemiologia , Terapia Assistida por Computador/métodos , Terapia Assistida por Computador/estatística & dados numéricos , Resultado do Tratamento
15.
Rev Recent Clin Trials ; 10(2): 111-27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25845953

RESUMO

Current indications for implantable cardioverter defibrillators (ICDs) in patients with channelopathies and cardiomyopathies of non-ischemic origin are mainly based on non-randomized evidence. In patients with nonischemic dilated cardiomyopathy (NIDCM), there is a tendency towards a beneficial effect on total mortality of ICD therapy in patients with significant left ventricular (LV) dysfunction. Although an important reduction in sudden cardiac death (SCD) seems to be clearly demonstrated in these patients, a net beneficial effect on total mortality is unclear mostly in cases with good functional status. Risk stratification has been changing over the last two decades in patients with hypertrophic cardiomyopathy (HCM). Its risk profile has been delineated in parallel with the beneficial effect of ICD in high risk patients. Observational results based on "appropriate" ICD interventions do support its usefulness both in primary and secondary SCD prevention in these patients. Novel risk models quantify the rate of sudden cardiac death in these patients on individual basis. Less clear risk stratification is available for cases of arrhythmogenic right ventricular cardiomyopathy (ARVC) and in other uncommon familiar cardiomyopathies. Main features of risk stratification vary among the different channelopathies (long QT syndrome -LQTS-, Brugada syndrome, etc) with great debate on the management of asymptomatic patients. For most familiar cardiomyopathies, ICD therapy is the only accepted strategy in the prevention of SCD. So far, genetic testing has a limited role in risk evaluation and management of the individual patient. This review aims to summarize these criticisms and to refine the current indications of ICD implantation in patients with cardiomyopathies and major channelopathies.


Assuntos
Cardiomiopatias/complicações , Canalopatias/complicações , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Displasia Arritmogênica Ventricular Direita/complicações , Síndrome de Brugada/complicações , Cardiomiopatia Hipertrófica/complicações , Morte Súbita Cardíaca/epidemiologia , Árvores de Decisões , Humanos , Guias de Prática Clínica como Assunto , Medição de Risco
16.
JACC Clin Electrophysiol ; 1(5): 353-365, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29759462

RESUMO

OBJECTIVES: The aim of this study was to determine if noninvasive measurement of scar by contrast-enhanced magnetic resonance imaging (MRI)-based signal intensity (SI) mapping predicts ventricular tachycardia (VT) recurrence after endocardial ablation. BACKGROUND: Scar extension on voltage mapping predicts VT recurrence after ablation procedures. METHODS: A total of 46 consecutive patients with previous myocardial infarction (87% men, mean age 68 ± 9 years, mean left ventricular ejection fraction 36 ± 10%) who underwent VT substrate ablation before the implantation of a cardioverter-defibrillator were included. Before ablation, contrast-enhanced MRI was performed, and areas of endocardial and epicardial scarring and heterogeneous tissue were measured; averaged subendocardial and subepicardial signal intensities were projected onto 3-dimensional endocardial and epicardial shells in which dense scar, heterogeneous tissue, and normal tissue were differentiated. RESULTS: During a mean follow-up period of 32 ± 24 months 17 patients (37%) had VT recurrence. Patients with recurrence had larger scar and heterogeneous tissue areas on SI maps in both endocardium (81 ± 27 cm2 vs. 48 ± 21 cm2 [p = 0.001] and 53 ± 21 cm2 vs. 30 ± 15 cm2 [p = 0.001], respectively) and epicardium (76 ± 28 cm2 vs. 51 ± 29 cm2 [p = 0.032] and 59 ± 25 cm2 vs. 37 ± 19 cm2 [p = 0.008]). In the multivariate analysis, MRI endocardial scar extension was the only independent predictor of VT recurrence (hazard ratio: 1.310 [per 10 cm2]; 95% confidence interval: 1.051 to 1.632; p = 0.034). Freedom from VT recurrence was higher in patients with small endocardial scars by MRI (<65 cm2) than in those with larger scars (≥65 cm2) (85% vs. 20%, log-rank p = 0.018). CONCLUSIONS: Pre-procedure endocardial scar extension assessment by contrast-enhanced MRI predicts VT recurrence after endocardial substrate ablation. This information may be useful to select patients for ablation procedures.

17.
Am J Cardiol ; 113(5): 827-31, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24440330

RESUMO

The aim of this study is to evaluate the safety and feasibility of using the Amigo Remote Catheter System (RCS) in arrhythmia ablation procedures. Because Amigo allows the physician to operate all catheter function outside of the radiation field, operator exposure time was also evaluated. This is a nonrandomized, prospective clinical trial conducted at 1 site (identifier: NCT01834872). The study prospectively enrolled 50 consecutive patients (mean age 59 ± 15 years, 72% men) with any type of arrhythmia (23 atrial fibrillation ablation, 12 common atrial flutters, 10 patients with other supraventricular tachycardia, 4 ventricular tachycardia, and 1 patient with palpitations with no arrhythmia induced) referred for catheter ablation, in which we used RCS. Fifty matched ablation procedures (mean age 57 ± 14 years, 70% men) performed during the same time period, without RCS, were enrolled into the control group. Acute ablation success was 96% with RCS and 98% in the manual group. In only 2 cases, the physician switched to manual ablation (1 ventricular tachycardia and 1 accessory pathway) to complete the procedure. There were no complications related to the use of RCS. No differences were observed in total procedure time, total fluoroscopy time, or total radiofrequency delivery compared with the manual group. In procedures performed with RCS, the operator's fluoroscopy exposure time was reduced by 68 ± 16%. In conclusion, arrhythmia ablation with RCS is safe and feasible. Furthermore, it significantly reduces operator's exposure to radiation.


Assuntos
Arritmias Cardíacas/cirurgia , Ablação por Cateter/instrumentação , Ablação por Cateter/métodos , Sistema de Condução Cardíaco/cirurgia , Adulto , Idoso , Fibrilação Atrial/cirurgia , Flutter Atrial/cirurgia , Técnicas Eletrofisiológicas Cardíacas , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Estudos Prospectivos , Taquicardia Ventricular/cirurgia
18.
Europace ; 14(11): 1560-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22696516

RESUMO

AIMS: Research on paroxysmal atrial fibrillation (AF) assumes that fibrillation induced by rapid pacing adequately reproduces spontaneously occurring paroxysmal AF in humans. We aimed to compare the spectral properties of spontaneous vs. induced AF episodes in paroxysmal AF patients. METHODS AND RESULTS: Eighty-five paroxysmal AF patients arriving in sinus rhythm to the electrophysiology laboratory were evaluated prior to ablation. Atrial fibrillation was induced by rapid pacing from the pulmonary vein-left atrial junctions (PV-LAJ), the coronary sinus (CS), or the high right atrium (HRA). Simultaneous recordings were obtained using multipolar catheters. Off-line power spectral analysis of 5 s bipolar electrograms was used to determine dominant frequency (DF) at recording sites with regularity index >0.2. Sixty-eight episodes were analysed for DF. Comparisons were made between spontaneous (n = 23) and induced (n = 45) AF episodes at each recording site. No significant differences were observed between spontaneous and induced AF episodes in HRA (5.18 ± 0.69 vs. 5.06 ± 0.91 Hz; P = 0.64), CS (5.27 ± 0.69 vs. 5.36 ± 0.76 Hz; P = 0.69), or LA (5.72 ± 0.88 vs. 5.64 ± 0.75 Hz; P = 0.7) regardless of pacing site. Consistent with these results, paired analysis in seven patients with both spontaneous and induced AF episodes, showed no regional DFs differences. Moreover, a left-to-right DF gradient was also present in both spontaneous (PV-LAJ 5.71 ± 0.81 vs. HRA 5.18 ± 0.69 Hz; P = 0.005) and induced (PV-LAJ 5.62 ± 0.72 vs. HRA 5.07 ± 0.91 Hz; P = 0.002) AF episodes, with no differences between them (P = not specific). CONCLUSION: In patients with paroxysmal AF, high-rate pacing-induced AF adequately mimics spontaneously initiated AF, regardless of induction site.


Assuntos
Fibrilação Atrial/diagnóstico , Estimulação Cardíaca Artificial , Técnicas Eletrofisiológicas Cardíacas , Sistema de Condução Cardíaco/fisiopatologia , Potenciais de Ação , Adulto , Fibrilação Atrial/etiologia , Fibrilação Atrial/fisiopatologia , Distribuição de Qui-Quadrado , Seio Coronário/fisiopatologia , Feminino , Átrios do Coração/fisiopatologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Veias Pulmonares/fisiopatologia , Processamento de Sinais Assistido por Computador , Fatores de Tempo , Imagens com Corantes Sensíveis à Voltagem
19.
J Transplant ; 2012: 603769, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22363835

RESUMO

The relationship between the use of immunosuppressants in solid-organ transplant patients and oral tissue abnormalities has been recognized. The objective of this study was to determine the state of oral tissue integrity in renal, heart, and liver transplant patients who are on continuous medical and dental control. Forty patients of both sexes were clinically evaluated at the Clinical Hospital of the University of Chile to identify pathologies of oral mucosa, gingival enlargement (GE), decayed, missing, filled teeth (DMFT) index, and salivary flow. The average age of the transplant subjects was 49.4 years, and the age range was 19 to 69 years. Most subjects maintained a good level of oral hygiene, and the rate mean of DMFT was 14.7. The degree of involvement of the oral mucosa and GE was low (10%). Unlike other studies, the frequency of oral mucosal diseases and GE was low despite the fact that these patients were immunosuppressed. Care and continuous monitoring seem to be of vital importance in maintaining the oral health of transplant patients.

20.
Biochem Biophys Res Commun ; 419(2): 405-11, 2012 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-22349506

RESUMO

Human equilibrative nucleoside transporter 1 (hENT1) is an important determinant for nucleoside analog based chemotherapy success. Preliminary data suggest hENT1 regulation by PPARs. Using A2780 cells, we investigated the role of PPARs on hENT1 expression and activity. PPARα and PPARγ agonists, Wy14,643 and RGZ, increased hENT1 expression, but only PPARα activation or overexpression resulted in higher hENT1 transport activity. On the other hand, promoter analysis showed two putative PPRE in hENT1 promoter and luciferase-coupled promoter constructs were generated and analyzed. Our results suggest that PPARα-but not PPARγ-mediated expression regulation of hENT1 is PPRE-dependent. In conclusion, PPARα and PPARγ activation modulate hENT1 expression.


Assuntos
Transportador Equilibrativo 1 de Nucleosídeo/genética , Regulação da Expressão Gênica , PPAR alfa/metabolismo , PPAR gama/metabolismo , Linhagem Celular , Humanos , PPAR alfa/agonistas , PPAR gama/agonistas , Regiões Promotoras Genéticas , Pirimidinas/farmacologia , Transfecção , Regulação para Cima
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