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1.
Ann Noninvasive Electrocardiol ; 28(1): e13021, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36436199

RESUMO

BACKGROUND: Patients with heart failure (HF) represent a large population of patients who are at high risk for complications related to undiagnosed atrial fibrillation (AF). However, currently there are limited modalities available for early AF detection in this high-risk population. An implantable cardiac monitor (ICM) is inserted subcutaneously and can provide long-term arrhythmia information via remote monitoring. METHODS AND RESULTS: Confirm-AF is a prospective randomized, nonblinded, two arm, multicenter clinical trial to be performed in the United States, enrolling 477 patients with a history of HF hospitalization and left ventricular ejection fraction >35% from 30 medical sites. Patients will be randomized in a 2:1 fashion to undergo ICM implant with remote monitoring and symptom-triggered mobile app transmissions versus (vs.) Non-ICM management and follow-up. The primary objective of this trial is to compare the time to first detection of AF lasting > 5 min using an Abbott ICM compared to non-ICM monitoring in symptomatic HF patients. This article describes the design and analytic plan for the Confirm-AF trial. CONCLUSIONS: The Confirm-AF trial seeks to accurately define the burden of AF in high-risk HF patients with LVEF > 35% using an Abbott ICM. A finding showing significantly higher incidence of AF along with improved clinical outcomes with ICM monitoring is expected to have substantial clinical implications and may change the method of monitoring high-risk HF patients.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Humanos , Estados Unidos , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Estudos Prospectivos , Volume Sistólico , Eletrocardiografia , Eletrocardiografia Ambulatorial/métodos , Função Ventricular Esquerda , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico
2.
JAMA ; 327(15): 1456-1468, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35381069

RESUMO

Importance: Corticosteroids improve strength and function in boys with Duchenne muscular dystrophy. However, there is uncertainty regarding the optimum regimen and dosage. Objective: To compare efficacy and adverse effects of the 3 most frequently prescribed corticosteroid regimens in boys with Duchenne muscular dystrophy. Design, Setting, and Participants: Double-blind, parallel-group randomized clinical trial including 196 boys aged 4 to 7 years with Duchenne muscular dystrophy who had not previously been treated with corticosteroids; enrollment occurred between January 30, 2013, and September 17, 2016, at 32 clinic sites in 5 countries. The boys were assessed for 3 years (last participant visit on October 16, 2019). Interventions: Participants were randomized to daily prednisone (0.75 mg/kg) (n = 65), daily deflazacort (0.90 mg/kg) (n = 65), or intermittent prednisone (0.75 mg/kg for 10 days on and then 10 days off) (n = 66). Main Outcomes and Measures: The global primary outcome comprised 3 end points: rise from the floor velocity (in rise/seconds), forced vital capacity (in liters), and participant or parent global satisfaction with treatment measured by the Treatment Satisfaction Questionnaire for Medication (TSQM; score range, 0 to 100), each averaged across all study visits after baseline. Pairwise group comparisons used a Bonferroni-adjusted significance level of .017. Results: Among the 196 boys randomized (mean age, 5.8 years [SD, 1.0 years]), 164 (84%) completed the trial. Both daily prednisone and daily deflazacort were more effective than intermittent prednisone for the primary outcome (P < .001 for daily prednisone vs intermittent prednisone using a global test; P = .017 for daily deflazacort vs intermittent prednisone using a global test) and the daily regimens did not differ significantly (P = .38 for daily prednisone vs daily deflazacort using a global test). The between-group differences were principally attributable to rise from the floor velocity (0.06 rise/s [98.3% CI, 0.03 to 0.08 rise/s] for daily prednisone vs intermittent prednisone [P = .003]; 0.06 rise/s [98.3% CI, 0.03 to 0.09 rise/s] for daily deflazacort vs intermittent prednisone [P = .017]; and -0.004 rise/s [98.3% CI, -0.03 to 0.02 rise/s] for daily prednisone vs daily deflazacort [P = .75]). The pairwise comparisons for forced vital capacity and TSQM global satisfaction subscale score were not statistically significant. The most common adverse events were abnormal behavior (22 [34%] in the daily prednisone group, 25 [38%] in the daily deflazacort group, and 24 [36%] in the intermittent prednisone group), upper respiratory tract infection (24 [37%], 19 [29%], and 24 [36%], respectively), and vomiting (19 [29%], 17 [26%], and 15 [23%]). Conclusions and Relevance: Among patients with Duchenne muscular dystrophy, treatment with daily prednisone or daily deflazacort, compared with intermittent prednisone alternating 10 days on and 10 days off, resulted in significant improvement over 3 years in a composite outcome comprising measures of motor function, pulmonary function, and satisfaction with treatment; there was no significant difference between the 2 daily corticosteroid regimens. The findings support the use of a daily corticosteroid regimen over the intermittent prednisone regimen tested in this study as initial treatment for boys with Duchenne muscular dystrophy. Trial Registration: ClinicalTrials.gov Identifier: NCT01603407.


Assuntos
Glucocorticoides , Distrofia Muscular de Duchenne , Prednisona , Criança , Pré-Escolar , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Humanos , Masculino , Distrofia Muscular de Duchenne/tratamento farmacológico , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Pregnenodionas/efeitos adversos
3.
Ann Noninvasive Electrocardiol ; 25(4): e12744, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31994819

RESUMO

BACKGROUND: Implantation of the subcutaneous implantable cardioverter-defibrillator (S-ICD) is spreading and has been shown to be safe and effective; however, it does not provide brady-pacing. Currently, data on the need for brady-pacing and cardiac resynchronization therapy (CRT) implantation in patients with ICD indication are limited. METHODS: The Multicenter Automatic Defibrillator Implantation Trial (MADIT)-II enrolled post-MI patients with reduced ejection fraction (EF ≤ 35%), randomized to either an implantable cardioverter-defibrillator (ICD) or conventional medical therapy. Kaplan-Meier analyses and multivariate Cox models were performed to assess the incidence and predictors of pacemaker (PM), or CRT implantation in the conventional arm of MADIT-II, after excluding 32 patients (6.5%) with a previously implanted PM. RESULTS: During the median follow-up of 20 months, 24 of 458 patients (5.2%) were implanted with a PM or a CRT (19 PM, 5 CRT). Symptomatic sinus bradycardia was the primary indication for PM implantation (n = 9, 37%), followed by AV block (n = 5, 21%), tachy-brady syndrome (n = 4, 17%), and carotid sinus hypersensitivity (n = 1, 4%). Baseline PR interval >200 ms (HR = 3.07, 95% CI: 1.24-7.57, p = .02), and CABG before enrollment (HR = 6.88, 95% CI: 1.58-29.84, p = .01) predicted subsequent PM/CRT implantation. Patients with PM/CRT implantation had a significantly higher risk for heart failure (HR = 2.67, 95% CI = 1.38-5.14, p = .003), but no increased mortality risk (HR = 1.06, 95% CI = 0.46-2.46, p = .89). CONCLUSION: The short-term need for ventricular pacing or CRT implantation in patients with MADIT-II ICD indication was low, especially in those with a normal baseline PR interval, and such patients are appropriate candidates for the subcutaneous ICD.


Assuntos
Terapia de Ressincronização Cardíaca/métodos , Desfibriladores Implantáveis/estatística & dados numéricos , Cardiopatias/terapia , Marca-Passo Artificial/estatística & dados numéricos , Idoso , Feminino , Cardiopatias/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Resultado do Tratamento
4.
JAMA ; 322(18): 1799-1805, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31714987

RESUMO

Importance: The incidence of chemotherapy-induced cardiomyopathy is increasing and is associated with poor clinical outcomes. Objective: To assess the association of cardiac resynchronization therapy (CRT) with improvement in cardiac function, as well as clinical improvement in patients with chemotherapy-induced cardiomyopathy. Design, Setting, and Participants: The Multicenter Automatic Defibrillator Implantation Trial-Chemotherapy-Induced Cardiomyopathy was an uncontrolled, prospective, cohort study conducted between November 21, 2014, and June 21, 2018, at 12 tertiary centers with cardio-oncology programs in the United States. Thirty patients were implanted with CRT owing to reduced left ventricular ejection fraction (LVEF≤35%), New York Heart Association class II-IV heart failure symptoms, and wide QRS complex, with established chemotherapy-induced cardiomyopathy and were followed up for 6 months after CRT implantation. The date of final follow-up was February 6, 2019. Exposures: CRT implantation according to standard of care. Main Outcomes and Measures: The primary end point was change in LVEF from baseline to 6 months after initiating CRT. Secondary outcomes included all-cause mortality and change in left ventricular end-systolic volume and end-diastolic volume. Results: Among 30 patients who were enrolled (mean [SD] age, 64 [11] years; 26 women [87%]; 73% had a history of breast cancer; 20% had a history of lymphoma or leukemia), primary end point data were available for 26 patients and secondary end point data were available for 23 patients. Patients had nonischemic cardiomyopathy with left bundle branch block, median LVEF of 29%, and a mean QRS duration of 152 ms. Patients with CRT experienced a statistically significant improvement in mean LVEF at 6 months from 28% to 39% (difference, 10.6% [95% CI, 8.0%-13.3%]; P < .001). This was accompanied by a reduction in LV end-systolic volume from 122.7 to 89.0 mL (difference, 37.0 mL [95% CI, 28.2-45.8]) and reduction in LV end-diastolic volume from 171.0 to 143.2 mL (difference, 31.9 mL [95% CI, 22.1-41.6]) (both P < .001). Adverse events included a procedure-related pneumothorax (1 patient), a device pocket infection (1 patient), and heart failure requiring hospitalization during follow-up (1 patient). Conclusions and Relevance: In this preliminary study of patients with chemotherapy-induced cardiomyopathy, CRT was associated with improvement in LVEF after 6 months. The findings are limited by the small sample size, short follow-up, and absence of a control group. Trial Registration: ClinicalTrials.gov Identifier: NCT02164721.


Assuntos
Terapia de Ressincronização Cardíaca , Cardiomiopatias/fisiopatologia , Volume Sistólico , Idoso , Antineoplásicos/efeitos adversos , Dispositivos de Terapia de Ressincronização Cardíaca , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/terapia , Desfibriladores Implantáveis , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Disfunção Ventricular Esquerda
5.
N Engl J Med ; 370(18): 1694-701, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24678999

RESUMO

BACKGROUND: The Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy (MADIT-CRT) showed that early intervention with cardiac-resynchronization therapy with a defibrillator (CRT-D) in patients with an electrocardiographic pattern showing left bundle-branch block was associated with a significant reduction in heart-failure events over a median follow-up of 2.4 years, as compared with defibrillator therapy alone. METHODS: We evaluated the effect of CRT-D on long-term survival in the MADIT-CRT population. Post-trial follow-up over a median period of 5.6 years was assessed among all 1691 surviving patients (phase 1) and subsequently among 854 patients who were enrolled in post-trial registries (phase 2). All reported analyses were performed on an intention-to-treat basis. RESULTS: At 7 years of follow-up after initial enrollment, the cumulative rate of death from any cause among patients with left bundle-branch block was 18% among patients randomly assigned to CRT-D, as compared with 29% among those randomly assigned to defibrillator therapy alone (adjusted hazard ratio in the CRT-D group, 0.59; 95% confidence interval [CI], 0.43 to 0.80; P<0.001). The long-term survival benefit of CRT-D in patients with left bundle-branch block did not differ significantly according to sex, cause of cardiomyopathy, or QRS duration. In contrast, CRT-D was not associated with any clinical benefit and possibly with harm in patients without left bundle-branch block (adjusted hazard ratio for death from any cause, 1.57; 95% CI, 1.03 to 2.39; P=0.04; P<0.001 for interaction of treatment with QRS morphologic findings). CONCLUSIONS: Our findings indicate that in patients with mild heart-failure symptoms, left ventricular dysfunction, and left bundle-branch block, early intervention with CRT-D was associated with a significant long-term survival benefit. (Funded by Boston Scientific; ClinicalTrials.gov numbers, NCT00180271, NCT01294449, and NCT02060110.).


Assuntos
Bloqueio de Ramo/terapia , Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca/terapia , Idoso , Bloqueio de Ramo/complicações , Terapia Combinada , Desfibriladores Implantáveis , Feminino , Seguimentos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/prevenção & controle , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Índice de Gravidade de Doença , Volume Sistólico , Disfunção Ventricular Esquerda/complicações
6.
Am Heart J ; 189: 158-166, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28625372

RESUMO

Patients with diabetes mellitus, prior myocardial infarction, older age, and a relatively preserved left ventricular ejection fraction remain at risk for sudden cardiac death that is potentially amenable by the subcutaneous implantable cardioverter defibrillator with a good risk-benefit profile. The launched MADIT S-ICD study is designed to test the hypothesis that post-myocardial infarction diabetes patients with relatively preserved ejection fraction of 36%-50% will have a survival benefit from a subcutaneous implantable cardioverter defibrillator.


Assuntos
Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Infarto do Miocárdio/complicações , Idoso , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Estudos Prospectivos , Taxa de Sobrevida/tendências , Resultado do Tratamento , Estados Unidos/epidemiologia
7.
N Engl J Med ; 367(24): 2275-83, 2012 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-23131066

RESUMO

BACKGROUND: The implantable cardioverter-defibrillator (ICD) is highly effective in reducing mortality among patients at risk for fatal arrhythmias, but inappropriate ICD activations are frequent, with potential adverse effects. METHODS: We randomly assigned 1500 patients with a primary-prevention indication to receive an ICD with one of three programming configurations. The primary objective was to determine whether programmed high-rate therapy (with a 2.5-second delay before the initiation of therapy at a heart rate of ≥200 beats per minute) or delayed therapy (with a 60-second delay at 170 to 199 beats per minute, a 12-second delay at 200 to 249 beats per minute, and a 2.5-second delay at ≥250 beats per minute) was associated with a decrease in the number of patients with a first occurrence of inappropriate antitachycardia pacing or shocks, as compared with conventional programming (with a 2.5-second delay at 170 to 199 beats per minute and a 1.0-second delay at ≥200 beats per minute). RESULTS: During an average follow-up of 1.4 years, high-rate therapy and delayed ICD therapy, as compared with conventional device programming, were associated with reductions in a first occurrence of inappropriate therapy (hazard ratio with high-rate therapy vs. conventional therapy, 0.21; 95% confidence interval [CI], 0.13 to 0.34; P<0.001; hazard ratio with delayed therapy vs. conventional therapy, 0.24; 95% CI, 0.15 to 0.40; P<0.001) and reductions in all-cause mortality (hazard ratio with high-rate therapy vs. conventional therapy, 0.45; 95% CI, 0.24 to 0.85; P=0.01; hazard ratio with delayed therapy vs. conventional therapy, 0.56; 95% CI, 0.30 to 1.02; P=0.06). There were no significant differences in procedure-related adverse events among the three treatment groups. CONCLUSIONS: Programming of ICD therapies for tachyarrhythmias of 200 beats per minute or higher or with a prolonged delay in therapy at 170 beats per minute or higher, as compared with conventional programming, was associated with reductions in inappropriate therapy and all-cause mortality during long-term follow-up. (Funded by Boston Scientific; MADIT-RIT ClinicalTrials.gov number, NCT00947310.).


Assuntos
Desfibriladores Implantáveis , Taquicardia/terapia , Idoso , Desfibriladores Implantáveis/efeitos adversos , Desenho de Equipamento , Falha de Equipamento , Feminino , Seguimentos , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Taquicardia/diagnóstico , Taquicardia/mortalidade , Fatores de Tempo
8.
J Card Fail ; 19(3): 149-55, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23482074

RESUMO

BACKGROUND: Cardiac resynchronization therapy (CRT) improves left ventricular (LV) function, size, mitral regurgitation, and clinical outcomes. Whether these improvements are due to the short-term effects of improvement in synchrony or contractile performance, or to long-term improvement in ventricular structure and function remains insufficiently elucidated. METHODS AND RESULTS: We used echocardiographic data from 63 patients enrolled in the MADIT-CRT trial who, after 1 year of CRT therapy, underwent echocardiographic evaluation with CRT turned both on and off within minutes. LV volumes, LV ejection fraction, left atrial (LA) volumes, and right ventricular function were assessed at baseline and in the on and off modes within a 5-minute time-frame at 12 months. Speckle-tracking strain analysis was used to assess LV dyssynchrony and contractile function. Interruption of long-term CRT resulted in acute deterioration of LV and RV function and acute increase in LV and LA volumes, although not to baseline. Acute withdrawal was also associated with increased dyssynchrony (SD time to peak transverse strain 178 ± 68 ms vs 195 ± 62 ms; P = .16; and SD time to peak longitudinal strain 108 ± 46 ms vs 125 ± 55 ms; P = .046). However, there was no deterioration in contractile function (global longitudinal strain), which had improved with CRT (-9.8 ± 4.3% vs -10.0 ± 3.7%; P = .93). CONCLUSIONS: Despite substantial LV reverse remodeling with CRT, interruption of long-term CRT after 12 months resulted in an acute worsening of LV size and function, LA volumes, and right ventricular function, with concomitant worsening of ventricular synchrony despite minimal change to the observed improvement in LV strain measures of contractile function. These findings suggest that the beneficial reverse remodeling associated with CRT may be mostly dependent on active pacing, although intrinsic improvements in contractile function may persist beyond termination of pacing.


Assuntos
Terapia de Ressincronização Cardíaca/métodos , Insuficiência Cardíaca/terapia , Contração Miocárdica/fisiologia , Função Ventricular Esquerda/fisiologia , Função Ventricular Direita/fisiologia , Suspensão de Tratamento , Idoso , Feminino , Insuficiência Cardíaca/classificação , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , New York , Método Simples-Cego , Fatores de Tempo , Resultado do Tratamento , Remodelação Ventricular/fisiologia , Suspensão de Tratamento/tendências
9.
N Engl J Med ; 361(14): 1329-38, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19723701

RESUMO

BACKGROUND: This trial was designed to determine whether cardiac-resynchronization therapy (CRT) with biventricular pacing would reduce the risk of death or heart-failure events in patients with mild cardiac symptoms, a reduced ejection fraction, and a wide QRS complex. METHODS: During a 4.5-year period, we enrolled and followed 1820 patients with ischemic or nonischemic cardiomyopathy, an ejection fraction of 30% or less, a QRS duration of 130 msec or more, and New York Heart Association class I or II symptoms. Patients were randomly assigned in a 3:2 ratio to receive CRT plus an implantable cardioverter-defibrillator (ICD) (1089 patients) or an ICD alone (731 patients). The primary end point was death from any cause or a nonfatal heart-failure event (whichever came first). Heart-failure events were diagnosed by physicians who were aware of the treatment assignments, but they were adjudicated by a committee that was unaware of assignments. RESULTS: During an average follow-up of 2.4 years, the primary end point occurred in 187 of 1089 patients in the CRT-ICD group (17.2%) and 185 of 731 patients in the ICD-only group (25.3%) (hazard ratio in the CRT-ICD group, 0.66; 95% confidence interval [CI], 0.52 to 0.84; P=0.001). The benefit did not differ significantly between patients with ischemic cardiomyopathy and those with nonischemic cardiomyopathy. The superiority of CRT was driven by a 41% reduction in the risk of heart-failure events, a finding that was evident primarily in a prespecified subgroup of patients with a QRS duration of 150 msec or more. CRT was associated with a significant reduction in left ventricular volumes and improvement in the ejection fraction. There was no significant difference between the two groups in the overall risk of death, with a 3% annual mortality rate in each treatment group. Serious adverse events were infrequent in the two groups. CONCLUSIONS: CRT combined with ICD decreased the risk of heart-failure events in relatively asymptomatic patients with a low ejection fraction and wide QRS complex. (ClinicalTrials.gov number, NCT00180271.)


Assuntos
Estimulação Cardíaca Artificial , Cardioversão Elétrica , Insuficiência Cardíaca/terapia , Idoso , Desfibriladores Implantáveis , Intervalo Livre de Doença , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Marca-Passo Artificial , Volume Sistólico
10.
Ann Noninvasive Electrocardiol ; 17(3): 176-85, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22816536

RESUMO

The implantable cardioverter defibrillator (ICD) is highly effective in reducing mortality due to cardiac arrhythmias in high-risk cardiac patients. However, inappropriate therapies caused predominantly by supraventricular tachyarrhythmias (SVTs) remain a significant side effect of ICD therapy despite medical treatment, affecting 8-40% of patients. The MADIT-RIT is a global, prospective, randomized, nonblinded, three-arm, multicenter clinical investigation to be performed in the Unites States, Europe, Canada, Israel and Japan, and will utilize approximately 90 centers with plan to enroll 1500 patients programmed to three treatment arms. The objective of the MADIT-RIT trial is to determine if dual-chamber ICD or CRT-D devices with high rate cutoff (MADIT-RIT-Arm B) and/or long delay in combination with detection enhancements (MADIT-RIT-Arm C) are associated with fewer patients experiencing inappropriate therapies than standard programming (MADIT-RIT-Arm A) during postimplant follow-up of patients with indication for primary prevention device therapy. This paper describes design and analytic plan for the MADIT-RIT trial.


Assuntos
Arritmias Cardíacas/terapia , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis/estatística & dados numéricos , Erros Médicos/prevenção & controle , Taquicardia Supraventricular/etiologia , Adulto , Idoso , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/mortalidade , Canadá , Desfibriladores Implantáveis/efeitos adversos , Desenho de Equipamento , Segurança de Equipamentos , Europa (Continente) , Feminino , Humanos , Israel , Japão , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Valores de Referência , Medição de Risco , Análise de Sobrevida , Taquicardia Supraventricular/mortalidade , Resultado do Tratamento , Estados Unidos
11.
Eur Heart J ; 32(21): 2697-704, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21642283

RESUMO

AIMS: We aimed to evaluate within the MADIT-CRT database whether different enrollment characteristics between US and non-US centres affected the clinical course of study patients. METHODS AND RESULTS: We evaluated differences in baseline characteristics, procedure-associated complications, clinical as well as echocardiographic response to cardiac resynchronization therapy with a defibrillator (CRT-D), between patients enrolled in 87 US centres (n = 1271) and 23 non-US centres (n = 549) in MADIT-CRT. Non-US patients displayed significant differences in baseline characteristics from US patients, including a higher frequency of left bundle branch block, a more advanced heart failure (HF) functional class >3 months prior to enrollment, and larger baseline cardiac volumes. Procedure-related complications occurred at a significantly higher frequency among patients enrolled in non-US centres (17%) than among those enrolled in US centres (10%; P < 0.001). During follow-up, CRT-D was associated with 42% (P = 0.003) and 38% (P < 0.001) reductions in the risk of HF or death in the two respective groups (P for the difference = 0.80), and with similar reductions in cardiac volumes (all P > 0.10). Subgroup analysis showed a more pronounced effect of CRT-D among women in the US group, including a significant 71% (P = 0.02) reduction in the risk of death, whereas CRT-D therapy was associated with a significant clinical benefit in men only in the non-US group. CONCLUSION: Patients enrolled in US and non-US centres in MADIT-CRT displayed significant differences in baseline clinical and echocardiographic characteristics and in the frequency of procedure-related complications, but experienced an overall similar clinical and echocardiographic response to CRT-D.


Assuntos
Terapia de Ressincronização Cardíaca/normas , Unidades de Cuidados Coronarianos/estatística & dados numéricos , Desfibriladores Implantáveis/normas , Insuficiência Cardíaca/terapia , Admissão do Paciente/estatística & dados numéricos , Adulto , Idoso , Terapia de Ressincronização Cardíaca/efeitos adversos , Terapia de Ressincronização Cardíaca/estatística & dados numéricos , Desfibriladores Implantáveis/efeitos adversos , Desfibriladores Implantáveis/estatística & dados numéricos , Ecocardiografia/estatística & dados numéricos , Europa (Continente) , Feminino , Humanos , Israel , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento , Estados Unidos , Adulto Jovem
12.
Eur Heart J ; 32(13): 1622-30, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21075774

RESUMO

AIMS: There are no data regarding the differential response to cardiac resynchronization therapy with defibrillator (CRT-D) by the aetiology of cardiomyopathy in mildly symptomatic patients. We evaluated the outcome of patients enrolled in MADIT-CRT by ischaemic and non-ischaemic aetiology of cardiomyopathy (ICM and non-ICM, respectively). METHODS AND RESULTS: The clinical response to CRT-D was assessed among ICM (n = 1046) and non-ICM (n = 774) patients enrolled in MADIT-CRT during an average follow-up of 2.4 years, and echocardiographic response was assessed at 1 year. Cardiac resynchronization therapy with defibrillator vs. ICD therapy was associated with respective 34% (P = 0.001) and 44% (P = 0.002) reductions in the risk of heart failure or death among ICM and non-ICM patients (P for interaction = 0.455). In the ICM group, CRT-D was associated with mean (±SD) 29 ± 14% and 18 ± 10% reductions in left ventricular end-systolic volume (LVESV) and left ventricular end-diastolic volume (LVEDV), respectively. In the non-ICM group, CRT-D was associated with significantly greater volume reductions compared with the ICM group [37 ± 16% and 24 ± 12% reductions in LVESV and LVEDV, respectively (P < 0.001 for all)]. Risk subsets in the ICM group that showed a favourable clinical response to CRT-D included patients with QRS ≥150 ms, systolic blood pressure <115 mmHg, and left bundle branch block (LBBB), whereas in the non-ICM group females, patients with diabetes mellitus, and LBBB, displayed a favourable clinical response. CONCLUSION: Mildly symptomatic ICM and non-ICM patients show significant differences in the echocardiographic response to CRT-D and in the clinical benefit within risk subsets suggesting that risk assessment for CRT-D in this population should be aetiology-specific.


Assuntos
Terapia de Ressincronização Cardíaca/métodos , Cardiomiopatias/terapia , Desfibriladores Implantáveis , Insuficiência Cardíaca/prevenção & controle , Isquemia Miocárdica/terapia , Idoso , Terapia de Ressincronização Cardíaca/mortalidade , Cardiomiopatias/complicações , Cardiomiopatias/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Isquemia Miocárdica/mortalidade , Medição de Risco , Volume Sistólico/fisiologia , Resultado do Tratamento , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/prevenção & controle
13.
Circulation ; 122(13): 1265-71, 2010 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-20837894

RESUMO

BACKGROUND: The Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II) showed a significant 31 reduction in the risk of death with primary implantable cardioverter-defibrillator (ICD) therapy during a median follow-up of 1.5 years. However, currently there are no data on the long-term efficacy of primary defibrillator therapy. METHODS AND RESULTS: MADIT-II enrolled 1232 patients with ischemic left ventricular dysfunction who were randomized to ICD and non-ICD medical therapy and were followed up through November 2001. For the present long-term study, we acquired posttrial mortality data through March 2009 for all study participants (median follow-up, 7.6 years). Multivariate Cox proportional hazards regression modeling was performed to calculate the hazard ratio for ICD versus non-ICD therapy during long-term follow-up. At 8 years of follow-up, the cumulative probability of all-cause mortality was 49 among patients treated with an ICD compared with 62 among non-ICD patients (P<0.001). Multivariate analysis demonstrated that ICD therapy was associated with a significant long-term survival benefit (hazard ratio for 0- through 8-year mortality=0.66 [95 confidence interval, 0.56 to 0.78]; P<0.001). Treatment with an ICD was shown to be associated with a significant reduction in the risk of death during the early phase of the extended follow-up period (0 through 4 years: hazard ratio=0.61 [95 confidence interval, 0.50 to 0.76]; P<0.001) and with continued life-saving benefit during the late phase of follow-up (5 through 8 years: hazard ratio=0.74 [95 confidence interval, 0.57 to 0.96]; P=0.02). CONCLUSIONS: Our findings demonstrate a sustained 8-year survival benefit with primary ICD therapy in the MADIT-II population.


Assuntos
Desfibriladores Implantáveis , Infarto do Miocárdio/prevenção & controle , Infarto do Miocárdio/terapia , Idoso , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
14.
Circulation ; 122(10): 985-92, 2010 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-20733097

RESUMO

BACKGROUND: Cardiac resynchronization therapy (CRT) plus implantation of an implantable cardioverter defibrillator (ICD) reduced the risk of death or heart failure event in patients with mildly symptomatic heart failure, left ventricular dysfunction, and wide QRS complex compared with an ICD only. We assessed echocardiographic changes in patients enrolled in the MADIT-CRT trial (Multicenter Automatic Defibrillator Implantation Trial: Cardiac Resynchronization Therapy) to evaluate whether the improvement in outcomes with CRT plus an ICD was associated with favorable alterations in cardiac size and function. METHODS AND RESULTS: A total of 1,820 patients were randomly assigned to CRT plus an ICD or to an ICD only in a 3:2 ratio. Echocardiographic studies were obtained at baseline and 12 months later in 1,372 patients. We compared changes in cardiac size and performance between treatment groups and assessed the relationship between these changes over the first year, as well as subsequent outcomes. Compared with the ICD-only group, the CRT-plus-ICD group had greater improvement in left ventricular end-diastolic volume index (-26.2 versus -7.4 mL/m(2)), left ventricular end-systolic volume index (-28.7 versus -9.1 mL/m(2)), left ventricular ejection fraction (11% versus 3%), left atrial volume index (-11.9 versus -4.7 mL/m(2)), and right ventricular fractional area change (8% versus 5%; P<0.001 for all). Improvement in end-diastolic volume at 1 year was predictive of subsequent death or heart failure, with adjustment for baseline covariates and treatment group; each 10% decrease in end-diastolic volume was associated with a 40% reduction in risk (P<0.001). CONCLUSIONS: CRT resulted in significant improvement in cardiac size and performance compared with an ICD-only strategy in patients with mildly symptomatic heart failure. Improvement in these measures accounted for the outcomes benefit. Clinical Trial Registration Information- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00180271.


Assuntos
Estimulação Cardíaca Artificial , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Insuficiência Cardíaca/terapia , Disfunção Ventricular Esquerda/terapia , Remodelação Ventricular , Idoso , Morte Súbita Cardíaca/epidemiologia , Ecocardiografia , Eletrocardiografia , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/epidemiologia , Insuficiência da Valva Mitral/terapia , Fatores de Risco , Índice de Gravidade de Doença , Volume Sistólico , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/epidemiologia
15.
Heart Rhythm O2 ; 1(5): 376-384, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34113895

RESUMO

BACKGROUND: Outcomes of patients with nonischemic cardiomyopathy and low ejection fraction implanted with an implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy with a defibrillator (CRT-D), especially in contemporary, real-life cohorts, are not fully understood. OBJECTIVE: We aimed to better characterize outcomes of death and ventricular tachyarrhythmias in patients with nonischemic cardiomyopathy, implanted with an ICD or CRT-D, and specifically assess differences by sex. METHODS: The AnaLysIs of Both Sex and Device Specific FactoRs on Outcomes in PAtients with Non-Ischemic Cardiomyopathy (BIO-LIBRA) study was designed to prospectively assess outcomes of device-treated ventricular tachyarrhythmias and all-cause mortality events in nonischemic cardiomyopathy patients, indicated for an ICD or CRT-D implantation for the primary prevention of sudden cardiac death (SCD), with a specific focus on sex differences. We will enroll a total of 1000 subjects across 50 U.S. sites and follow patients for up to 3 years. RESULTS: The primary objective of BIO-LIBRA is to evaluate the combined risk of all-cause mortality and treated ventricular tachycardia (VT) or ventricular fibrillation (VF) events by subject sex and by implanted device type. We will also assess all-cause mortality, VT or VF alone, cardiac death, and SCD in the total cohort, as well as by subject sex and by the implanted device type. In addition, the previously validated Seattle Proportional Risk Model (SPRM) will be used to compare the SPRM predicted incidence of SCD to the observed incidence. CONCLUSIONS: The BIO-LIBRA study will provide novel and contemporary information regarding outcomes in patients with a NICM who receive a defibrillator.

17.
J Am Coll Cardiol ; 72(6): 636-645, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30071993

RESUMO

BACKGROUND: Ventricular tachycardia (VT) and ventricular fibrillation (VF) remain a challenging problem in patients with implantable cardioverter-defibrillators (ICDs). OBJECTIVES: This study aimed to determine whether ranolazine administration decreases the likelihood of VT, VF, or death in patients with an ICD. METHODS: This was double-blind, placebo-controlled clinical trial in which high-risk ICD patients with ischemic or nonischemic cardiomyopathy were randomized to 1,000 mg ranolazine twice a day or placebo. The primary endpoint was VT or VF requiring appropriate ICD therapy or death, whichever occurred first. Pre-specified secondary endpoints included ICD shock for VT, VF, or death and recurrent VT or VF requiring ICD therapy. RESULTS: Among 1,012 ICD patients (510 randomized to ranolazine and 502 to placebo) the mean age was 64 ± 10 years and 18% were women. During 28 ± 16 months of follow-up there were 372 (37%) patients with primary endpoint, 270 (27%) patients with VT or VF, and 148 (15%) deaths. The blinded study drug was discontinued in 199 (39.6%) patients receiving placebo and in 253 (49.6%) patients receiving ranolazine (p = 0.001). The hazard ratio for ranolazine versus placebo was 0.84 (95% confidence interval: 0.67 to 1.05; p = 0.117) for VT, VF, or death. In a pre-specified secondary analysis, patients randomized to ranolazine had a marginally significant lower risk of ICD therapies for recurrent VT or VF (hazard ratio: 0.70; 95% confidence interval: 0.51 to 0.96; p = 0.028). There were no other significant treatment effects in other pre-specified secondary analyses, which included individual components of the primary endpoint, inappropriate shocks, cardiac hospitalizations, and quality of life. CONCLUSIONS: In high-risk ICD patients, treatment with ranolazine did not significantly reduce the incidence of the first VT or VF, or death. However, the study was underpowered to detect a difference in the primary endpoint. In prespecified secondary endpoint analyses, ranolazine administration was associated with a significant reduction in recurrent VT or VF requiring ICD therapy without evidence for increased mortality. (Ranolazine Implantable Cardioverter-Defibrillator Trial [RAID]; NCT01215253).


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Desfibriladores Implantáveis/tendências , Ranolazina/uso terapêutico , Taquicardia Ventricular/prevenção & controle , Fibrilação Ventricular/prevenção & controle , Idoso , Desfibriladores Implantáveis/efeitos adversos , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Taquicardia Ventricular/epidemiologia , Taquicardia Ventricular/fisiopatologia , Fibrilação Ventricular/epidemiologia , Fibrilação Ventricular/fisiopatologia
18.
Trials ; 19(1): 291, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29793540

RESUMO

BACKGROUND: Trials in rare diseases have many challenges, among which are the need to set up multiple sites in different countries to achieve recruitment targets and the divergent landscape of clinical trial regulations in those countries. Over the past years, there have been initiatives to facilitate the process of international study set-up, but the fruits of these deliberations require time to be operationally in place. FOR-DMD (Finding the Optimum Steroid Regimen for Duchenne Muscular Dystrophy) is an academic-led clinical trial which aims to find the optimum steroid regimen for Duchenne muscular dystrophy, funded by the National Institutes of Health (NIH) for 5 years (July 2010 to June 2015), anticipating that all sites (40 across the USA, Canada, the UK, Germany and Italy) would be open to recruitment from July 2011. However, study start-up was significantly delayed and recruitment did not start until January 2013. METHOD: The FOR-DMD study is used as an example to identify systematic problems in the set-up of international, multi-centre clinical trials. The full timeline of the FOR-DMD study, from funding approval to site activation, was collated and reviewed. Systematic issues were identified and grouped into (1) study set-up, e.g. drug procurement; (2) country set-up, e.g. competent authority applications; and (3) site set-up, e.g. contracts, to identify the main causes of delay and suggest areas where anticipatory action could overcome these obstacles in future studies. RESULTS: Time from the first contact to site activation across countries ranged from 6 to 24 months. Reasons of delay were universal (sponsor agreement, drug procurement, budgetary constraints), country specific (complexity and diversity of regulatory processes, indemnity requirements) and site specific (contracting and approvals). The main identified obstacles included (1) issues related to drug supply, (2) NIH requirements regarding contracting with non-US sites, (3) differing regulatory requirements in the five participating countries, (4) lack of national harmonisation with contracting and the requirement to negotiate terms and contract individually with each site and (5) diversity of languages needed for study materials. Additionally, as with many academic-led studies, the FOR-DMD study did not have access to the infrastructure and expertise that a contracted research organisation could provide, organisations often employed in pharmaceutical-sponsored studies. This delay impacted recruitment, challenged the clinical relevance of the study outcomes and potentially delayed the delivery of the best treatment to patients. CONCLUSION: Based on the FOR-DMD experience, and as an interim solution, we have devised a checklist of steps to not only anticipate and minimise delays in academic international trial initiation but also identify obstacles that will require a concerted effort on the part of many stakeholders to mitigate.


Assuntos
Lista de Checagem , Ensaios Clínicos como Assunto/métodos , Estudos Multicêntricos como Assunto/métodos , Distrofia Muscular de Duchenne/tratamento farmacológico , Doenças Raras/tratamento farmacológico , Projetos de Pesquisa , Esteroides/administração & dosagem , Orçamentos , Ensaios Clínicos como Assunto/economia , Ensaios Clínicos como Assunto/legislação & jurisprudência , Contratos , Humanos , Cooperação Internacional , Estudos Multicêntricos como Assunto/economia , Estudos Multicêntricos como Assunto/legislação & jurisprudência , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/economia , Seleção de Pacientes , Doenças Raras/diagnóstico , Doenças Raras/economia , Projetos de Pesquisa/legislação & jurisprudência , Apoio à Pesquisa como Assunto , Esteroides/efeitos adversos , Esteroides/provisão & distribuição , Fatores de Tempo , Resultado do Tratamento
19.
N Engl J Med ; 346(12): 877-83, 2002 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-11907286

RESUMO

BACKGROUND: Patients with reduced left ventricular function after myocardial infarction are at risk for life-threatening ventricular arrhythmias. This randomized trial was designed to evaluate the effect of an implantable defibrillator on survival in such patients. METHODS: Over the course of four years, we enrolled 1232 patients with a prior myocardial infarction and a left ventricular ejection fraction of 0.30 or less. Patients were randomly assigned in a 3:2 ratio to receive an implantable defibrillator (742 patients) or conventional medical therapy (490 patients). Invasive electrophysiological testing for risk stratification was not required. Death from any cause was the end point. RESULTS: The clinical characteristics at base line and the prevalence of medication use at the time of the last follow-up visit were similar in the two treatment groups. During an average follow-up of 20 months, the mortality rates were 19.8 percent in the conventional-therapy group and 14.2 percent in the defibrillator group. The hazard ratio for the risk of death from any cause in the defibrillator group as compared with the conventional-therapy group was 0.69 (95 percent confidence interval, 0.51 to 0.93; P=0.016). The effect of defibrillator therapy on survival was similar in subgroup analyses stratified according to age, sex, ejection fraction, New York Heart Association class, and the QRS interval. CONCLUSIONS: In patients with a prior myocardial infarction and advanced left ventricular dysfunction, prophylactic implantation of a defibrillator improves survival and should be considered as a recommended therapy.


Assuntos
Arritmias Cardíacas/prevenção & controle , Desfibriladores Implantáveis , Infarto do Miocárdio/terapia , Disfunção Ventricular Esquerda/terapia , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Amiodarona/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Antiarrítmicos/uso terapêutico , Arritmias Cardíacas/etiologia , Terapia Combinada , Desfibriladores Implantáveis/efeitos adversos , Feminino , Humanos , Hipolipemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Modelos de Riscos Proporcionais , Volume Sistólico , Análise de Sobrevida , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/mortalidade
20.
Contemp Clin Trials ; 58: 34-39, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28450193

RESUMO

Despite corticosteroids being the only treatment documented to improve strength and function in boys with Duchenne muscular dystrophy (DMD) corticosteroid prescription is inconsistent and in some countries, corticosteroids are not prescribed. We are conducting a clinical trial that (1) compares the 3 most frequently prescribed corticosteroid regimes; (2) standardizes treatment of DMD complications; and (3) standardizes prevention of corticosteroid side effects. Investigators at 38 sites in 5 countries plan to recruit 300 boys aged 4-7 who are randomly assigned to one of three regimens: daily prednisone; daily deflazacort; or intermittent prednisone (10days on/10days off). Boys are followed for a minimum of 3years to assess the relative effectiveness and adverse event profiles of the different regimens. The primary outcome is a 3-dimensional variable consisting of log-transformed time to rise from the floor, forced vital capacity, and subject/parent satisfaction with treatment, each averaged over all post-baseline visits. The study protocol includes evidence- and consensus-based treatment of DMD complications and of corticosteroid side effects. This study seeks to establish a standard corticosteroid regimen for DMD. Since all new interventions for DMD are being developed as add-on therapies to corticosteroids, defining the optimum regimen is of importance for all new treatments.


Assuntos
Imunossupressores/uso terapêutico , Distrofia Muscular de Duchenne/tratamento farmacológico , Prednisona/administração & dosagem , Pregnenodionas/uso terapêutico , Criança , Pré-Escolar , Avaliação da Deficiência , Método Duplo-Cego , Esquema de Medicação , Testes de Função Cardíaca , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Masculino , Força Muscular , Satisfação do Paciente , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Pregnenodionas/administração & dosagem , Pregnenodionas/efeitos adversos , Amplitude de Movimento Articular , Projetos de Pesquisa , Capacidade Vital
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