Primary care REFerral for EchocaRdiogram (REFER) in heart failure: a diagnostic accuracy study.

BACKGROUND: Symptoms of breathlessness, fatigue, and ankle swelling are common in general practice but deciding which patients are likely to have heart failure is challenging. AIM: To evaluate the performance of a clinical decision rule (CDR), with or without N-Terminal pro-B type natriuretic peptide (NT-proBNP) assay, for identifying heart failure. DESIGN AND SETTING: Prospective, observational, diagnostic validation study of patients aged >55 years, presenting with shortness of breath, lethargy, or ankle oedema, from 28 general practices in England. METHOD: The outcome was test performance of the CDR and natriuretic peptide test in determining a diagnosis of heart failure. The reference standard was an expert consensus panel of three cardiologists. RESULTS: Three hundred and four participants were recruited, with 104 (34.2%; 95% confidence interval [CI] = 28.9 to 39.8) having a confirmed diagnosis of heart failure. The CDR+NT-proBNP had a sensitivity of 90.4% (95% CI = 83.0 to 95.3) and specificity 45.5% (95% CI = 38.5 to 52.7). NT-proBNP level alone with a cut-off <400 pg/ml had sensitivity 76.9% (95% CI = 67.6 to 84.6) and specificity 91.5% (95% CI = 86.7 to 95.0). At the lower cut-off of NT-proBNP <125 pg/ml, sensitivity was 94.2% (95% CI = 87.9 to 97.9) and specificity 49.0% (95% CI = 41.9 to 56.1). CONCLUSION: At the low threshold of NT-proBNP <125 pg/ml, natriuretic peptide testing alone was better than a validated CDR+NT-proBNP in determining which patients presenting with symptoms went on to have a diagnosis of heart failure. The higher NT-proBNP threshold of 400 pg/ml may mean more than one in five patients with heart failure are not appropriately referred. Guideline natriuretic peptide thresholds may need to be revised.

Observational longitudinal cohort study to determine progression to heart failure in a screened community population: the Echocardiographic Heart of England Screening Extension (ECHOES-X) study.

OBJECTIVES: Rescreen a large community cohort to examine the progression to heart failure over time and the role of natriuretic peptide testing in screening. DESIGN: Observational longitudinal cohort study. SETTING: 16 socioeconomically diverse practices in central England. PARTICIPANTS: Participants from the original Echocardiographic Heart of England Screening (ECHOES) study were invited to attend for rescreening. OUTCOME MEASURES: Prevalence of heart failure at rescreening overall and for each original ECHOES subgroup. Test performance of N Terminal pro-B-type Natriuretic Peptide (NT-proBNP) levels at different thresholds for screening. RESULTS: 1618 of 3408 participants underwent screening which represented 47% of survivors and 26% of the original ECHOES cohort. A total of 176 (11%, 95% CI 9.4% to 12.5%) participants were classified as having heart failure at rescreening; 103 had heart failure with reduced ejection fraction (HFREF) and 73 had heart failure with preserved ejection fraction (HFPEF). Sixty-eight out of 1232 (5.5%, 95% CI 4.3% to 6.9%) participants who were recruited from the general population over the age of 45 and did not have heart failure in the original study, had heart failure on rescreening. An NT-proBNP cut-off of 400 pg/mL had sensitivity for a diagnosis of heart failure of 79.5% (95% CI 72.4% to 85.5%) and specificity of 87% (95% CI 85.1% to 88.8%). CONCLUSIONS: Rescreening identified new cases of HFREF and HFPEF. Progression to heart failure poses a significant threat over time. The natriuretic peptide cut-off level for ruling out heart failure must be low enough to ensure cases are not missed at screening.

Prevalencia de la fibrilación auricular en la población general y en grupos de alto riesgo: estudio ECHOES

Resumen Objetivos: establecer la prevalencia de la fibrilación auricular (FA) en la población general en el Reino Unido y en los individuos con factores de riesgo. Método y resultados: se estableció la prevalencia de la FA electrocardiográfica en grupos seleccionados de forma prospectiva; se seleccionaron aleatoriamente 3.960 individuos de la población, mayores de 45 años; 782 tenían diagnóstico previo de insuficiencia cardíaca y 1.062 con antecedente de infarto de miocardio, hipertensión, angina de pecho o diabetes. Los pacientes también fueron evaluados clínicamente y mediante ecocardiografía. Se hizo un seguimiento de la mortalidad durante ocho años. Se encontró FA en 78 de la muestra aleatoria de la población (2,0%). La prevalencia fue de 1,6% en las mujeres y de 2,4% en los hombres, aumentando con la edad, yendo desde 0,2% en los sujetos de entre 45 y 54 años, hasta 8,0% en los de 75 años o mayores. La mitad de todos los casos eran en pacientes de 75 años o mayores. Solo 23 de los 78 (29,5%) con diagnóstico de FA estaban recibiendo warfarina. De los 782 pacientes, 175 (22,4%) con diagnóstico de insuficiencia cardíaca presentaban FA, y 95 (54,3%) de ellos tenían una función ventricular izquierda normal. Se constató FA en 14 de los 244 (5,7%) pacientes con antecedentes de infarto de miocardio; en 15 de los 388 (3,9%) pacientes con hipertensión; en 15 de los 321 (4,7%) pacientes con angina, y en 11 de los 208 (5,3%) pacientes diabéticos. Ajustando por edad y sexo, la mortalidad fue 1,57 veces mayor en quienes presentaban FA. Conclusión: la FA es frecuente en ancianos y en personas con factores de riesgo clínico. Un tamizaje de estos grupos permitiría identificar a muchos individuos con FA. El uso de anticoagulación era bajo en la época en que se hizo la evaluación inicial, a fines de los años 90, pero la práctica puede haber cambiado en los últimos tiempos.

Summary Aim: To establish the prevalence of atrial fibrillation (AF) in the general population in the UK, and in those with risk factors. Methods and results: The prevalence of AF on electrocardiography was established in prospectively selected groups: 3960 randomly selected from the population, aged 45+; 782 with a previous diagnosis of heart failure; and 1062 with a record of myocardial infarction, hypertension, angina, or diabetes. Patients were also assessed clinically and with echocardiography. Mortality was tracked for 8 years. Atrial fibrillation was found in 78 of the random population sample (2.0%). Prevalence was 1.6% in women and 2.4% in men, rising with age from 0.2% in those aged 45-54 to 8.0% in those aged 75 and older. Half of all cases were in patients aged 75 and older. Only 23 of the 78 (29.5%) of those in AF took warfarin. Of the 782 patients, 175 (22.4%) with a diagnosis of heart failure were in AF, with normal left ventricular function in 95 (54.3%) of these. Atrial fibrillation was found in 14 of the 244 (5.7%) of those with a history of myocardial infarction, 15 of the 388 (3.9%) of those with hypertension, 15 of the 321 (4.7%) of those with angina, and 11 of the 208 (5.3%) of diabetics. Adjusting for age and sex, mortality was 1.57 times higher for those in AF. Conclusion: Atrial fibrillation is common in the elderly and those with clinical risk factors. Screening these groups would identify many with AF. Use of anticoagulation was low at the time of the initial assessments in the late 1990s; practice may have changed recently

The REFER (REFer for EchocaRdiogram) protocol: a prospective validation of a clinical decision rule, NT-proBNP, or their combination, in the diagnosis of heart failure in primary care. Rationale and design.

BACKGROUND: Heart failure is a major cause of mortality and morbidity. As mortality rates are high, it is important that patients seen by general practitioners with symptoms suggestive of heart failure are identified quickly and treated appropriately. Identifying patients with heart failure or deciding which patients need further tests is a challenge. All patients with suspected heart failure should be diagnosed using objective tests such as echocardiography, but it is expensive, often delayed, and limited by the significant skill shortage of trained echocardiographers. Alternative approaches for diagnosing heart failure are currently limited. Clinical decision tools that combine clinical signs, symptoms or patient characteristics are designed to be used to support clinical decision-making and validated according to strict methodological procedures. The REFER Study aims to determine the accuracy and cost-effectiveness of our previously derived novel, simple clinical decision rule, a natriuretic peptide assay, or their combination, in the triage for referral for echocardiography of symptomatic adult patients who present in general practice with symptoms suggestive of heart failure. METHODS/DESIGN: This is a prospective, Phase II observational, diagnostic validation study of a clinical decision rule, natriuretic peptides or their combination, for diagnosing heart failure in primary care. Consecutive adult primary care patients 55 years of age or over presenting to their general practitioner with a chief complaint of recent new onset shortness of breath, lethargy or peripheral ankle oedema of over 48 hours duration, with no obvious recurrent, acute or self-limiting cause will be enrolled. Our reference standard is based upon a three step expert specialist consensus using echocardiography and clinical variables and tests. DISCUSSION: Our clinical decision rule offers a potential solution to the diagnostic challenge of providing a timely and accurate diagnosis of heart failure in primary care. Study results will provide an evidence-base from which to develop heart failure care pathway recommendations and may be useful in standardising care. If demonstrated to be effective, the clinical decision rule will be of interest to researchers, policy makers and general practitioners worldwide. TRIAL REGISTRATION: ISRCTN17635379.

Prevalence of atrial fibrillation in the general population and in high-risk groups: the ECHOES study.

AIMS: To establish the prevalence of atrial fibrillation (AF) in the general population in the UK, and in those with risk factors. METHODS AND RESULTS: The prevalence of AF on electrocardiography was established in prospectively selected groups: 3960 randomly selected from the population, aged 45+; 782 with a previous diagnosis of heart failure; and 1062 with a record of myocardial infarction, hypertension, angina, or diabetes. Patients were also assessed clinically and with echocardiography. Mortality was tracked for 8 years. Atrial fibrillation was found in 78 of the random population sample (2.0%). Prevalence was 1.6% in women and 2.4% in men, rising with age from 0.2% in those aged 45-54 to 8.0% in those aged 75 and older. Half of all cases were in patients aged 75 and older. Only 23 of the 78 (29.5%) of those in AF took warfarin. Of the 782 patients, 175 (22.4%) with a diagnosis of heart failure were in AF, with normal left ventricular function in 95 (54.3%) of these. Atrial fibrillation was found in 14 of the 244 (5.7%) of those with a history of myocardial infarction, 15 of the 388 (3.9%) of those with hypertension, 15 of the 321 (4.7%) of those with angina, and 11 of the 208 (5.3%) of diabetics. Adjusting for age and sex, mortality was 1.57 times higher for those in AF. CONCLUSION: Atrial fibrillation is common in the elderly and those with clinical risk factors. Screening these groups would identify many with AF. Use of anticoagulation was low at the time of the initial assessments in the late 1990s; practice may have changed recently.

Ten-year prognosis of heart failure in the community: follow-up data from the Echocardiographic Heart of England Screening (ECHOES) study.

AIMS: This study investigates the 10-year survival in the ECHOES (Echocardiographic Heart of England Screening) study and examines factors associated with prognosis. METHODS AND RESULTS: A prospective study was carried out to investigate 10-year survival in those with heart failure (HF) and/or left ventricular systolic dysfunction (LVSD). The mean age of participants in ECHOES was 64, and 50% were male. Records of all 6162 screened participants were flagged, and deaths up to 25 February 2009 were coded. Causes of death were categorized according to diagnosis on death certificate. Kaplan-Meier curves and log rank tests were used to compare survival times of participants with HF and LVSD in different diagnostic groups. A Cox proportional hazards regression model was used to identify variables associated with risk of death. A total of 2062 of the 6162 (33.5%) participants had died at the census date in February 2009. Of these deaths, 902 (43.7%) were due to cardiovascular disease, including 263 (12.8%) due to HF. Ten-year survival was 75% for participants without HF, 26.7% for those with HF, 37.6% for those with LVSD, and 27.4% for those with HF and LVSD. Multiple-cause HF had a 10-year survival of 11.6%. Multiple variables including diabetes, valvular disease, diuretic use, and a previous label of HF, as well as lifestyle factors such as smoking and obesity, were associated with increased risk of death. CONCLUSIONS: Patients with HF and LVSD have a poor prognosis. However, the mortality rates of all-cause, all-stage HF as measured in the ECHOES cohort are around half those reported for patients diagnosed for the first time with HF during hospital admission.