RESUMO
BACKGROUND: Therapies for patients with chronic heart failure caused by left ventricular systolic dysfunction have advanced substantially over recent decades. The cumulative effect of these therapies on mortality, mode of death, symptoms, and clinical characteristics has yet to be defined. METHODS AND RESULTS: This study was a comparison of 2 prospective cohort studies of outpatients with chronic heart failure caused by left ventricular systolic dysfunction performed between 1993 and 1995 (historic cohort: n=281) and 2006 and 2009 (contemporary cohort: n=357). In the historic cohort, 83% were prescribed angiotensin-converting enzyme inhibitors and 8.5% were prescribed ß-adrenoceptor antagonists, compared with 89% and 80%, respectively, in the contemporary cohort. Mortality rates over the first year of follow-up declined from 12.5% to 7.8% between eras (P=0.04), and sudden death contributed less to contemporary mortality (33.6% versus 12.7%; P<0.001). New York Heart Association class declined between eras (P<0.001). QTc dispersion across the chest leads declined from 85 ms (SD, 2) to 34 ms (SD, 1) and left ventricular end-diastolic dimensions declined from 65 mm (SD, 0.6) to 59 mm (SD, 0.5) (both P<0.001). CONCLUSIONS: Survival has significantly improved in patients with chronic heart failure caused by left ventricular systolic dysfunction over the past 15 years; furthermore, sudden death makes a much smaller contribution to mortality, and noncardiac mortality is a correspondingly greater contribution. This has been accompanied by an improvement in symptoms and some markers of adverse electric and structural left ventricular remodeling.
Assuntos
Morte Súbita Cardíaca/epidemiologia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/mortalidade , Disfunção Ventricular Esquerda/complicações , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Terapia de Ressincronização Cardíaca , Estudos de Coortes , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Feminino , Seguimentos , Insuficiência Cardíaca/terapia , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida , Reino UnidoRESUMO
AIMS: The efficacy of cardioversion (DCCV) for restoration of sinus rhythm (SR) in persistent atrial fibrillation (AF) is limited by a high relapse rate. Relapse may be reduced by amiodarone but no placebo-controlled trials of efficacy have been performed and the appropriate duration of therapy is unknown. METHODS AND RESULTS: In this double-blind study, 161 subjects with persistent AF were randomized to one of three groups-placebo (n=38); amiodarone 400mg BD for 2 weeks prior to DCCV and 200mg daily for 8 weeks followed by placebo for 44 weeks (n=62, short-term amiodarone); amiodarone 400mg BD for 2 weeks then 200mg daily for 52 weeks (n=61, long-term amiodarone). Spontaneous reversion to SR occurred before DCCV in 21% (26/123) patients on amiodarone and none of the 38 patients on placebo (absolute difference 21%, 95% confidence interval (CI): 10 to 29%, P=0.002). At 8 weeks following DCCV, 51% (63/123) patients on amiodarone remained in SR compared to 16% (6/38) taking placebo (difference-35% 95% CI: -48 to -18%, P<0.001). At 1 year, 49% (30/61) patients on long-term amiodarone were in SR compared to 33% (21/62) taking short-term amiodarone (difference-15%, 95% CI: -31 to 2%, P=0.085). There was no difference in adverse event rate or quality of life scores between groups. CONCLUSIONS: Amiodarone pre-treatment before electrical DCCV for persistent AF allows chemical conversion in one-fifth of patients without altering the efficacy of subsequent DC conversion. Amiodarone is more effective than placebo in the maintenance of SR when continued for 8 weeks following successful DCCV. More patients taking long-term amiodarone remained in SR at 52 weeks, but more had serious adverse effects requiring discontinuation of therapy. Eight weeks of adjuvant therapy with amiodarone following successful DCCV may be the preferred option.
Assuntos
Amiodarona/uso terapêutico , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/terapia , Cardioversão Elétrica/métodos , Idoso , Amiodarona/efeitos adversos , Antiarrítmicos/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Terapia Combinada , Método Duplo-Cego , Cardioversão Elétrica/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Qualidade de VidaRESUMO
BACKGROUND: Chronic heart failure is characterized by left ventricular dilation and abnormalities of cardiac autonomic function. Up to 20% of patients with chronic heart failure have QRS prolongation, which can lead to asynchronous left ventricular contraction. We tested the hypotheses that in patients with chronic heart failure, QRS > 150 ms is a risk factor for additional abnormalities of ventricular morphology, heart rate variability, and increased mortality. METHODS AND RESULTS: In 184 patients with left ventricular ejection fraction < 35%, QRS duration was > 150 ms in 53, and = 150 ms in 131. We evaluated patients with baseline chest radiographs, echocardiograms, and Holter recordings. Patients with QRS duration above and below 150 ms were similar in age, sex, functional class, renal function, serum sodium, and ejection fraction. In patients with QRS > 150 ms, left ventricular end-diastolic and end-systolic diameters were greater than patients with QRS duration =150 ms (P <.01). Patients with QRS > 150 ms had less low frequency R-R interval spectral power (P <.04). At 5 years 60% of patients with QRS > 150 ms had died compared with 35% of patients with QRS =150 ms (P <.001). This increase in mortality was predominantly the result of an increase in progressive heart failure. CONCLUSIONS: Chronic heart failure patients with QRS duration > 150 ms have exaggerated disturbance of cardiac autonomic function, and left ventricular remodeling and significantly higher mortality than patients with QRS duration = 150 ms.