RESUMO
AIMS: Understanding of the pathophysiology of progressive heart failure (HF) in patients with heart failure with preserved ejection fraction (HFpEF) is incomplete. We sought to identify factors differentially associated with risk of progressive HF death and hospitalization in patients with HFpEF compared with patients with HF and reduced ejection fraction (HFrEF). METHODS AND RESULTS: Prospective cohort study of patients newly referred to secondary care with suspicion of HF, based on symptoms and signs of HF and elevated natriuretic peptides (NP), followed up for a minimum of 6 years. HFpEF and HFrEF were diagnosed according to the 2016 European Society of Cardiology guidelines. Of 960 patients referred, 467 had HFpEF (49%), 311 had HFrEF (32%), and 182 (19%) had neither. Atrial fibrillation (AF) was found in 37% of patients with HFpEF and 34% with HFrEF. During 6 years follow-up, 19% of HFrEF and 14% of HFpEF patients were hospitalized or died due to progressive HF, hazard ratio (HR) 0.67 (95% CI: 0.47-0.96; P = 0.028). AF was the only marker that was differentially associated with progressive HF death or hospitalization in patients with HFpEF HR 2.58 (95% CI: 1.59-4.21; P < 0.001) versus HFrEF HR 1.11 (95% CI: 0.65-1.89; P = 0.7). CONCLUSIONS: De novo patients diagnosed with HFrEF have greater risk of death or hospitalization due to progressive HF than patients with HFpEF. AF is associated with increased risk of progressive HF death or hospitalization in HFpEF but not HFrEF, raising the intriguing possibility that this may be a novel therapeutic target in this growing population.
Assuntos
Fibrilação Atrial , Insuficiência Cardíaca Diastólica , Insuficiência Cardíaca , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Volume Sistólico/fisiologia , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/diagnóstico , Estudos Prospectivos , Prognóstico , Insuficiência Cardíaca Diastólica/complicaçõesRESUMO
BACKGROUND: Heart failure with reduced ejection fraction (HFrEF) is characterized by blunting of the positive relationship between heart rate and left ventricular (LV) contractility known as the force-frequency relationship (FFR). We have previously described that tailoring the rate-response programming of cardiac implantable electronic devices in patients with HFrEF on the basis of individual noninvasive FFR data acutely improves exercise capacity. We aimed to examine whether using FFR data to tailor heart rate response in patients with HFrEF with cardiac implantable electronic devices favorably influences exercise capacity and LV function 6 months later. METHODS: We conducted a single-center, double-blind, randomized, parallel-group trial in patients with stable symptomatic HFrEF taking optimal guideline-directed medical therapy and with a cardiac implantable electronic device (cardiac resynchronization therapy or implantable cardioverter-defibrillator). Participants were randomized on a 1:1 basis between tailored rate-response programming on the basis of individual FFR data and conventional age-guided rate-response programming. The primary outcome measure was change in walk time on a treadmill walk test. Secondary outcomes included changes in LV systolic function, peak oxygen consumption, and quality of life. RESULTS: We randomized 83 patients with a mean±SD age 74.6±8.7 years and LV ejection fraction 35.2±10.5. Mean change in exercise time at 6 months was 75.4 (95% CI, 23.4 to 127.5) seconds for FFR-guided rate-adaptive pacing and 3.1 (95% CI, -44.1 to 50.3) seconds for conventional settings (analysis of covariance; P=0.044 between groups) despite lower peak mean±SD heart rates (98.6±19.4 versus 112.0±20.3 beats per minute). FFR-guided heart rate settings had no adverse effect on LV structure or function, whereas conventional settings were associated with a reduction in LV ejection fraction. CONCLUSIONS: In this phase II study, FFR-guided rate-response programming determined using a reproducible, noninvasive method appears to improve exercise time and limit changes to LV function in people with HFrEF and cardiac implantable electronic devices. Work is ongoing to confirm our findings in a multicenter setting and on longer-term clinical outcomes. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02964650.
Assuntos
Dispositivos de Terapia de Ressincronização Cardíaca , Terapia de Ressincronização Cardíaca , Desfibriladores Implantáveis , Cardioversão Elétrica/instrumentação , Tolerância ao Exercício , Insuficiência Cardíaca/terapia , Frequência Cardíaca , Volume Sistólico , Função Ventricular Esquerda , Idoso , Idoso de 80 Anos ou mais , Terapia de Ressincronização Cardíaca/efeitos adversos , Método Duplo-Cego , Cardioversão Elétrica/efeitos adversos , Inglaterra , Feminino , Estado Funcional , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Recuperação de Função Fisiológica , Fatores de Tempo , Resultado do Tratamento , Teste de CaminhadaRESUMO
BACKGROUND: The Surprise Question: 'would you be surprised if this patient were to die within the next year?' has been shown to predict mortality in patients with chronic kidney disease and cancer. This prospective study aimed to determine whether the Surprise Question could identify heart failure patients with a prognosis of less than 1 year, and whether the Surprise Question can be used by different healthcare professionals. METHODS AND RESULTS: Overall, 129 consecutive patients admitted with decompensated heart failure were included. Doctors and nurses were asked to provide a 'surprised' or 'not surprised' response to the Surprise Question for each patient. Patients were followed up until death or 1 year following study inclusion. The sensitivity, specificity, positive predictive value and negative predictive value of the Surprise Question were assessed. Cox regression was used to determine covariates significantly associated with survival. The Surprise Question showed excellent sensitivity (0.85) and negative predictive value (0.88) but only fair specificity (0.59) and positive predictive value (0.52) when asked of cardiologists. There were similar levels of accuracy between doctors and specialist nurses. The Surprise Question was significantly associated with all-cause mortality in multivariate regression analysis (hazard ratio 2.8, 95% confidence interval 1.0-7.9, P = 0.046). CONCLUSION: This study demonstrates that the Surprise Question can identify heart failure patients within the last year of life. Despite over-classification of patients into the 'not surprised' category, the Surprise Question identified nearly all patients who were within the last year of life, whilst also accurately identifying those unlikely to die.
Assuntos
Insuficiência Cardíaca/mortalidade , Cuidados Paliativos/métodos , Inquéritos e Questionários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida/tendências , Reino Unido/epidemiologiaRESUMO
AIMS: The UK National Institute for Health and Care Excellence (UK-NICE) and European Society of Cardiology (ESC) guidelines advise natriuretic peptide (NP) assessment in patients presenting to primary care with symptoms possibly due to chronic heart failure (HF), to determine need for specialist involvement. This prospective service evaluation aimed to describe the diagnostic and prognostic utility of these guidelines. METHODS AND RESULTS: We prospectively collected clinical, echocardiography and outcomes data (minimum 5 years) from all patients referred to the Leeds HF Service for 12 months of following the initiation of the NP-guideline-directed pathway. Between 1 May 2012 and 1 August 2013, 1020 people with symptoms possibly due to HF attended either with a raised NT-pro-BNP or a previous myocardial infarction (MI) with an overall rate of left ventricular systolic dysfunction (LVSD) of 33%. Of these, 991 satisfied the ESC criteria (NT-pro-BNP ≥125 pg/mL) in whom the rate of LVSD was 32%, and 821 the UK-NICE criteria in whom the rate of LVSD was 49% in those with a previous MI, 25% in those with NT-pro-BNP concentration 400-2000 pg/mL, and 54% in those with NT-pro-BNP concentration of >2000 pg/mL. An NT-pro-BNP concentration 125-400 pg/mL had a 12% risk of LVSD. Specificity was poor in women >70 years, who made up the largest proportion of attendees. Elevated NT-pro-BNP levels were associated with lower survival even in the absence of LVSD. CONCLUSION: In people referred through the ESC and UK-NICE guidelines, elevated NT-pro-BNP is a marker of increased mortality risk, but there is wide variation in specificity for LVSD. Age- and sex-adjusted criteria might improve performance.
Assuntos
Insuficiência Cardíaca/diagnóstico , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Atenção Primária à Saúde , Atenção Secundária à Saúde , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Encaminhamento e Consulta , Fatores de Tempo , Reino UnidoRESUMO
Background Noncardiovascular death is increasingly common in people with chronic heart failure ( CHF ), yet its causes remain poorly characterized. We aimed to define the prevalence of sepsis death in people with CHF and to ascertain its risk marker profile. Methods and Results We conducted a prospective cohort study of 1802 patients with CHF and left ventricular ejection fraction ≤45% attending CHF clinics in 4 United Kingdom hospitals between 2006 and 2014. Mode of death was defined over a 10.3-year follow-up period (mean 4 years). Competing risk regression defined mode-specific hazard ratios for sepsis, other noncardiovascular, progressive heart failure, and sudden cardiac death in relation to established heart failure prognostic markers. Of 737 deaths, 173 (23.5%) were due to sepsis; respiratory tract infections accounted for 69.9% (n=121) of these events. Those who died from sepsis were older, had higher platelet counts, and had a higher prevalence of chronic obstructive pulmonary disease than those who died from other causes. Sepsis death was independently associated with older age (hazard ratio=1.05; 95% confidence interval 1.03-1.07), greater prevalence of chronic obstructive pulmonary disease (2.43; 1.74-3.40), male sex (1.73; 1.16-2.60), lower log serum vitamin D (0.68; 0.49-0.95), and higher platelet count (1.002; 1.000-1.005) than nonsepsis death. Established heart failure prognostic markers exhibited different patterns of association with sepsis death, other noncardiovascular death, progressive heart failure death, and sudden cardiac death. Conclusions Sepsis is a major contributor to death in people with CHF and has a different risk marker profile from other modes of death, suggesting that it may be amenable to targeted preventative strategies.
Assuntos
Insuficiência Cardíaca/mortalidade , Sepse/mortalidade , Disfunção Ventricular Esquerda/mortalidade , Fatores Etários , Idoso , Doença Crônica , Morte Súbita Cardíaca/epidemiologia , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Prevalência , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/mortalidade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Sepse/fisiopatologia , Fatores Sexuais , Volume Sistólico/fisiologia , Reino Unido/epidemiologia , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
OBJECTIVE: To characterise the association between socioeconomic deprivation and adverse outcomes in patients with chronic heart failure (CHF). METHODS: We prospectively observed 1802 patients with CHF and left ventricular ejection fraction (LVEF) ≤45%, recruited in four UK hospitals between 2006 and 2014. We assessed the association between deprivation defined by the UK Index of Multiple Deprivation (IMD) and: mode-specific mortality (mean follow-up 4 years); mode-specific hospitalisation; and the cumulative duration of hospitalisation (after 1 year). RESULTS: A 45-point difference in mean IMD score was noted between patients residing in the least and most deprived quintiles of geographical regions. Deprivation was associated with age, sex and comorbidity, but not CHF symptoms, LVEF or prescribed drug therapy. IMD score was associated with the risk of age-sex adjusted all-cause mortality (6% higher risk per 10-unit increase in IMD score; 95% CI 2% to 10%; P=0.004), and non-cardiovascular mortality (9% higher risk per 10-unit increase in IMD score; 95% CI 3% to 16%; P=0.003), but not cardiovascular mortality. All-cause, but not heart failure-specific, hospitalisation was also more common in the most deprived patients. Overall, patients spent a cumulative 3.3 days in hospital during 1 year of follow-up, with IMD score being associated with the age-sex adjusted cumulative duration of hospitalisations (4% increase in duration per 10-unit increase in IMD score; 95% CI 3% to 6%; P<0.0005). CONCLUSIONS: Socioeconomic deprivation in people with CHF is linked to increased risk of death and hospitalisation due to an excess of non-cardiovascular events.
Assuntos
Insuficiência Cardíaca/mortalidade , Determinantes Sociais da Saúde , Fatores Socioeconômicos , Disfunção Ventricular Esquerda/mortalidade , Idoso , Doença Crônica , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Hospitalização , Humanos , Masculino , Pobreza , Prognóstico , Estudos Prospectivos , Fatores de Risco , Volume Sistólico , Fatores de Tempo , Reino Unido/epidemiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/terapia , Função Ventricular EsquerdaRESUMO
OBJECTIVES: This study sought to examine whether the heart rate (HR) at which the force-frequency relationship (FFR) slope peaks (critical HR) could be used to tailor HR response in chronic heart failure (CHF) patients with cardiac pacemakers and whether this favorably influences exercise capacity. BACKGROUND: CHF secondary to left ventricular (LV) systolic dysfunction is characterized by blunting of the positive relationship between HR and LV contractility known as the FFR. METHODS: This observational study was carried out in patients with CHF and healthy subjects with pacemaker devices. The study assessed the 3 important features of the FFR (critical HR, peak contractility, and the FFR slope), and their reproducibility was measured noninvasively using echocardiography. The investigators then undertook a double-blind, randomized, controlled crossover study comparing the effects of tailored pacemaker rate-response programming on the basis of the FFR with conventional rate-response programming on exercise time and maximal oxygen consumption. RESULTS: The study enrolled 90 patients with CHF into the observational cohort study: mean age, 73.6 ± 8.9 years; mean left ventricular ejection fraction (LVEF), 33.5 ± 10.9%. The study investigated 15 control subjects with normal LV function (LVEF, 55.6 ± 5.3%). The critical HR (103 ± 22 beats/min vs. 126 ± 15 beats/min; p = 0.0002), peak contractility (3.8 ± 3.7 SBP/LVESVI vs. 9.8 ± 4.1 SBP/LVESVI; p = 0.0001), and the slope of the FFR (p < 10-15) were lower in patients with CHF than in control subjects. A total of 52 patients, with a mean LVEF of 32 ± 11% on optimal therapy, took part in the crossover study. Rate-response settings limiting HR rise to below the critical HR led to greater exercise time (475 ± 189 s vs. 425 ± 196 s; p = 0.003) and higher peak oxygen consumption (17.3 ± 4.6 ml/kg/min vs. 16.6 ± 4.7 ml/kg/min; p = 0.01). CONCLUSIONS: A personalized approach to rate-response programming, determined using a reproducible noninvasive method for assessing the FFR, improves exercise time in patients with CHF and pacemaker devices. (Bowditch Revisited: Defining the Optimum Heart Rate Range in Chronic Heart Failure; NCT02563873).
Assuntos
Estimulação Cardíaca Artificial/métodos , Tolerância ao Exercício/fisiologia , Insuficiência Cardíaca/terapia , Frequência Cardíaca/fisiologia , Contração Miocárdica/fisiologia , Função Ventricular Esquerda/fisiologia , Idoso , Estudos Cross-Over , Método Duplo-Cego , Ecocardiografia , Teste de Esforço , Feminino , Seguimentos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Reprodutibilidade dos TestesRESUMO
OBJECTIVE: Define the real-world performance of recently updated National Institute for Health and Care Excellence guidelines (TA314) on implantable cardioverter-defibrillator (ICD) use in people with chronic heart failure. METHODS: Multicentre prospective cohort study of 1026 patients with stable chronic heart failure, associated with left ventricular ejection fraction (LVEF) ≤45% recruited in cardiology outpatient departments of four UK hospitals. We assessed the capacity of TA314 to identify patients at increased risk of sudden cardiac death (SCD) or appropriate ICD shock. RESULTS: The overall risk of SCD or appropriate ICD shock was 2.1 events per 100 patient-years (95% CI 1.7 to 2.6). Patients meeting TA314 ICD criteria (31.1%) were 2.5-fold (95% CI 1.6 to 3.9) more likely to suffer SCD or appropriate ICD shock; they were also 1.5-fold (95% CI 1.1 to 2.2) more likely to die from non-cardiovascular causes and 1.6-fold (95% CI 1.1 to 2.3) more likely to die from progressive heart failure. Patients with diabetes not meeting TA314 criteria experienced comparable absolute risk of SCD or appropriate ICD shock to patients without diabetes who met TA314 criteria. Patients with ischaemic cardiomyopathy not meeting TA314 criteria experienced comparable absolute risk of SCD or appropriate ICD shock to patients with non-ischaemic cardiomyopathy who met TA314 criteria. CONCLUSIONS: TA314 can identify patients with reduced LVEF who are at increased relative risk of sudden death. Clinicians should also consider clinical context and the absolute risk of SCD when advising patients about the potential risks and benefits of ICD therapy.
Assuntos
Morte Súbita Cardíaca/prevenção & controle , Técnicas de Apoio para a Decisão , Cardioversão Elétrica/instrumentação , Insuficiência Cardíaca/terapia , Guias de Prática Clínica como Assunto , Idoso , Causas de Morte , Doença Crônica , Desfibriladores Implantáveis/efeitos adversos , Desfibriladores Implantáveis/normas , Cardioversão Elétrica/efeitos adversos , Cardioversão Elétrica/mortalidade , Cardioversão Elétrica/normas , Inglaterra , Feminino , Fidelidade a Diretrizes , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Seleção de Pacientes , Guias de Prática Clínica como Assunto/normas , Modelos de Riscos Proporcionais , Falha de Prótese , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Volume Sistólico , Fatores de Tempo , Resultado do Tratamento , Função Ventricular EsquerdaRESUMO
BACKGROUND: Serum calcium (Ca) and inorganic phosphate (Pi) concentrations and calcium-phosphate product (CPP) levels are positively associated with worse outcomes in patients with chronic kidney disease, but there are few data for Pi or Ca and none for CPP in patients with chronic heart failure (CHF). METHODS: Unselected, consecutive patients with CHF (left ventricular ejection fraction, LVEF ≤45%) were enrolled in a prospective observational study for the occurrence of hospitalisation and mortality. Blood samples were collected at the time of recruitment and analysed immediately. RESULTS: Patients (n = 713) were on contemporary optimal treatment and mean (standard error, SE) follow-up was 765 (18.9) days. Mean (SE) Ca was 2.29 (0.004) mmol/l. Median (interquartile range, IQR) Pi was 1.11 (0.98-1.23) mmol/l and median CPP 2.53 (2.21-2.88) mmol(2)/l(2). LVEF correlated inversely with Ca, natural log-transformed (Ln)Pi, and LnCPP. There was no difference in CPP between classes of symptom severity or diabetes status. Ca and LnCPP (but not LnPi) were associated with total mortality. Ca was significantly associated with progressive HF and non-cardiovascular death but not with sudden death. Binary logistic regression analyses showed that LnPi and LnCPP were associated with risk of hospitalisation. CONCLUSIONS: Ca, Pi and CPP could be useful additional variables in determining risk in CHF patients. Further work is required to elucidate the mechanisms underlying the adverse influence and determine whether lowering phosphate levels per se in CHF patients is of benefit.
Assuntos
Cálcio/sangue , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Fosfatos/sangue , Disfunção Ventricular Esquerda/sangue , Idoso , Biomarcadores/sangue , Doença Crônica , Progressão da Doença , Feminino , Insuficiência Cardíaca/etiologia , Hospitalização , Humanos , Masculino , Prognóstico , Estudos Prospectivos , Volume Sistólico , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
INTRODUCTION: Patients with right ventricular pacemakers are at increased risk of left ventricular systolic dysfunction (LVSD). We aimed to establish the prevalence, degree and associations of LVSD in patients with long-term right ventricular pacemakers listed for pulse generator replacement (PGR). METHODS: All patients listed for PGR at Leeds General Infirmary were invited to attend for an assessment during which we recorded medical history, symptomatic status, medical therapy, date and indication of first implantation, the percentage of right ventricular pacing (% RVP) and an echocardiogram. RESULTS: We collected data on 491 patients. A left ventricular ejection fraction less than 50% was observed in 40% of our cohort, however, this was much higher (59%) in those with more than 80% RVP than in those with less than 80% RVP (22%) (Pâ<â0.0001). Multivariable analysis revealed % RVP, (but not complete heart block at baseline), serum creatinine and previous myocardial infarction to be independently related to the presence of LVSD. A model combining % RVP and previous myocardial infarction has a c-statistic of 0.74 for predicting LVSD. After a mean follow-up time of 668 days, 56 patients (12%) were dead or had been hospitalized for heart failure. In multivariable analysis, previous myocardial infarction and high % RVP were independently associated with a worse survival. CONCLUSION: Patients with right ventricular pacemakers have a high prevalence of LVSD, and this is greater in those exposed to more RVP. Those with LVSD and high amounts of RVP are at higher risk of hospitalization or death. Simple variables can identify those patients who might benefit from a more comprehensive review.
Assuntos
Estimulação Cardíaca Artificial/efeitos adversos , Insuficiência Cardíaca/terapia , Marca-Passo Artificial/efeitos adversos , Disfunção Ventricular Esquerda/etiologia , Idoso , Creatinina/sangue , Teste de Esforço/métodos , Feminino , Insuficiência Cardíaca/fisiopatologia , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Infarto do Miocárdio/complicações , Prognóstico , Fatores de Risco , Volume Sistólico/fisiologia , Ultrassonografia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/terapiaRESUMO
OBJECTIVE: Heart failure and left ventricular systolic dysfunction (LVSD) are common in patients with permanent pacemakers, but whether right ventricular (RV) pacing is contributory or merely a bystander in patients with more severe cardiac disease is controversial. The aim of the present study was to determine whether reprogramming of existing pacemakers to reduce RV pacing is safe and leads to improvements in cardiac function. METHODS: This was a prospective service evaluation of the effects of optimising pacemaker programming to avoid RV pacing in 66 consecutive attendees of a teaching hospital pacemaker clinic without complete heart block. The main outcome measures were left ventricular ejection fraction (LVEF), N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) levels, quality of life and cardiopulmonary exercise testing at baseline and after 6 months. RESULTS: At 6 months, the protocol reduced absolute RV pacing by a mean of 49% (95% CI 41% to 57%) (p<0.0001 from baseline) and resulted in a mean absolute improvement in LVEF of 6% (4% to 8%) (p<0.0001 from baseline) but no reduction in exercise capacity, NT-pro-BNP or quality of life. There was a relationship between the magnitude of change in EF and the reduction in RV pacing (p=0.04) and changes in NT-pro-BNP seemed to relate to change in RV pacing (p=0.07). CONCLUSIONS: Programming standard pacemakers to avoid RV pacing is safe, does not adversely affect patients' symptoms or quality of life and is associated with improved LV function, related to the reductions in RV pacing percentage.
Assuntos
Arritmias Cardíacas/terapia , Estimulação Cardíaca Artificial/efeitos adversos , Marca-Passo Artificial , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda/fisiologia , Idoso , Arritmias Cardíacas/fisiopatologia , Eletrocardiografia , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Estudos Prospectivos , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
AIMS: Heart failure and left ventricular (LV) systolic dysfunction (LVSD) are common in patients with permanent pacemakers. The aim was to determine if cardiac resynchronization therapy (CRT) at the time of pulse generator replacement (PGR) is of benefit in patients with unavoidable RV pacing and LVSD. METHODS AND RESULTS: Fifty patients with unavoidable RV pacing, LVSD, and mild or no symptoms of heart failure, listed for PGR were randomized 1 : 1 to either standard RV-PGR (comparator) or CRT. The primary endpoint was the difference in change in LV ejection fraction (LVEF) between RV-PGR and CRT groups from baseline to 6 months. Secondary endpoints included peak oxygen consumption, quality of life, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels. At 6 months there was a difference in change in median (interquartile range) LVEF [9 (6-12) vs. -1.5 (-4.5 to -0.8)%; P < 0.0001] between the CRT and RV-PGR arms. There were also improvements in exercise capacity (P = 0.007), quality of life (P = 0.03), and NT-proBNP (P = 0.007) in those randomized to CRT. After 809 (729-880) days, 17 patients had died or been hospitalized (6 in CRT group and 11 in the comparator RV-PGR group) and two patients in the RV-PGR arm had required CRT for deteriorating heart failure. Patients with standard RV-PGR had more days in hospital during follow-up than those in the CRT group [4 (2-7) vs. 11 (6-16) days; P = 0.047]. CONCLUSION: Performing CRT in pacemaker patients with unavoidable RV pacing and LVSD but without severe symptoms of heart failure, at the time of PGR, improves cardiac function, exercise capacity, quality of life, and NT-pro-BNP levels.