Clinical articles

In primary care, the significant burden of heart failure is exacerbated by problematic, inaccurate diagnosis that may produce inefficient triaging of patients to echocardiography. UK guidelines recommend using natriuretic peptides in the diagnostic pathway. The costs and consequences of providing a definitive diagnosis for symptomatic heart failure have not been established for peptide testing in primary care. We provide a cost-consequence analysis to compare alternative diagnostic strategies for symptomatic heart failure patients presenting to their GP.

Health economic evaluation using decision-tree modelling taking a cohort of patients presenting in primary care with symptomatic heart failure to a definitive diagnosis was performed. The model compared a diagnostic strategy using electrocardiograms (ECGs) interpreted by consultants with the use of B-type natriuretic peptide (BNP) assays. The base-case used data from the UK Natriuretic Peptide (UKNP) study, which used a ‘point-of-care’ assay. Two alternative scenarios were modelled reflecting data from key studies, as was sensitivity to costs. The model demonstrates that, for the base-case scenario, an initial diagnostic strategy of BNP is superior to ECG in terms of diagnosis of symptomatic heart failure in patients presenting in primary care, despite slightly more initial false negatives and a marginally higher cost. The alternative scenarios and sensitivity analyses show that the results are very sensitive to test accuracies and costs, but that, under plausible assumptions, BNP could be both cheaper and clinically superior.

The model suggests that, despite parameter uncertainty, the adoption of BNP in primary care is likely to be clinically preferable, be more satisfactory for most patients, and lead to fewer unnecessary echocardiography referrals, at a very small increase in cost.

A clinical audit of ezetimibe in the treatment of refractory hyperlipidaemia was conducted in 100 high-risk patients who failed to achieve desirable levels of total and low-density lipoprotein (LDL)-cholesterol on statins. Of these, 59 had familial hypercholesterolaemia (FH), the remainder had other aetiologies (non-FH). The percentage of patients achieving the total and LDL-cholesterol targets of the International Panel on the Management of FH or the Second Joint British Societies’ guidelines in non-FH patients was determined.

Ezetimibe significantly decreased mean LDL-cholesterol when used as an adjunct to statins or as monotherapy, from 3.9 to 3.1 mmol/L in FH, from 3.4 to 2.4 mmol/L in non-FH and from 6.0 to 4.4 mmol/L in statin-intolerant patients. The decrease in LDL-cholesterol on statins was inversely correlated with the decrement after adding ezetimibe (r= -0.67, p<0.0001) but 15% of patients showed no further decrease. The percentage of patients achieving target levels of LDL-cholesterol was 27% on statins and 63% on statins plus ezetimibe (p<0.007). None of the non-FH patients achieved target levels on statins but 33% did so when ezetimibe was added (p<0.001).

Ezetimibe is an effective adjunct to statins for lowering LDL-cholesterol in refractory hyperlipidaemia, except in a minority of patients, and is a useful substitute in statin-intolerant subjects.

Nicotinic acid (for treatment of low high-density lipoprotein [HDL]) combined with a statin has been shown previously to improve cardiovascular outcomes. To evaluate tolerability and safety of prolonged-release nicotinic acid added to statin therapy in patients at high cardiovascular risk, the Niaspan®-induced HDL-Elevation for Optimizing Risk Control (NEMO) study focused on 179 patients with atherogenic dyslipidaemia treated under usual-care conditions. Flushing was the most common treatment-related adverse drug reaction (ADR) in Ireland (32% flushed during the first month), followed by cutaneous (6.2%) and gastrointestinal (3.9%) ADRs. Mean HDL-cholesterol increased by 20%. Half of the patients elected to continue treatment after the study. In conclusion, the tolerability and safety of prolonged-release nicotinic acid was similar in Ireland compared with the overall NEMO population. It is important to take practical measures to optimise patient compliance to minimise overall cardiovascular risk.

We present a case in which the use of cardiovascular magnetic resonance (CMR) allowed the full pathology underlying syncope to be established.

Despite the major role of primary care in the management of people with, or at risk of developing, cardiovascular disease, little is known about the availability and state of readiness of cardiovascular diagnostic and monitoring equipment in general practice premises. We surveyed 170 general practices in one cardiac network. Our findings suggest that both provision of cardiac equipment, and training of staff in its use, is variable.

Patients with mechanical prosthetic heart valves require oral anticoagulation to reduce the risk of thromboembolic events, but this can be complicated by anticoagulant-associated intracerebral haemorrhage (ICH). In order to make appropriate decisions about the resumption of anticoagulation in patients with mechanical heart valves and ICH, the risks of further bleeding must be weighed against those of thromboembolic events. There is limited evidence available to guide clinical decision-making in this situation and each case must be assessed individually, ideally with a multi-disciplinary team approach.

The British Society of Echocardiography (BSE) Education Committee has published a minimum dataset of 24 views for acquiring a standard adult transthoracic echocardiogram. To establish adherence to the minimum dataset, and secondly to establish the indication for echocardiography, we performed a retrospective review of 961 patients’ echocardiogram images and a prospective review (re-audit) of 832 patients’ echocardiograms, following a programme of echocardiographer education. Images were obtained from a computerised database over three months. Subjects were adult patients referred to the cardiology department of a large tertiary hospital in Oxfordshire. Results showed 17 views were consistently obtained in over 78% of patients, irrespective of audit period. Seven views were obtained in less than 50% of patients; of these, five views were performed significantly more frequently during re-audit. Apical four chamber continuous wave Doppler across the tricuspid valve, and subcostal views were performed in less than 45% of patients; this did not increase during re-audit. The main indication for performing an echocardiogram was assessment of left ventricular function, followed by assessment of valve function and investigation of arrhythmia. In conclusion, all echocardiographers need to be made aware of, and adhere closely to the requirements of the minimum dataset.

In a retrospective longitudinal cohort study of 111 consecutive patients with suspected left ventricular systolic dysfunction (LVSD) referred for open-access echocardiography, patient’s views at one-year follow-up in terms of satisfaction with the service, ongoing symptoms and personal health beliefs were assessed. Eighty-five (76%) patients completed a one-year follow-up questionnaire. LVSD was identified in only 18 (16%) patients. While 93% of all patients found the echocardiogram useful, 27% of patients could not recall being informed of the result. Many patients remained undiagnosed and symptomatic at one year. The detection rate for LVSD by open-access echocardiography remains low despite the use of a structured referral letter and screening electrocardiogram and chest X-ray.

The incidence of statin intolerance due to non-severe side effects is estimated to be 5–10%. As an increasing number of patients become eligible for lipid-lowering treatment, this is becoming a more prevalent issue. Very limited, if any, data exist so far in the management of this subgroup of patients. Clinic letters from 1,100 patients who attended the Lipid Clinic at Hull Royal Infirmary from January 2000 until December 2004 were searched for ‘statin intolerance’. Forty patients (19 male, 21 female, median age 62 years) were identified with intolerance to at least one statin drug but with an absolute indication to be on treatment. Out of the 40 patients, 26 (65%, 11 male, 15 female) were eventually able to tolerate a statin for at least six months without their initial side effect, the most commonly successful statins being rosuvastatin (n=9) and pravastatin (n=8). Overall, this required a median of two switches (range one to four) in statin treatment. Fourteen (35%) were unable to continue treatment after a median of 1.5 switches (range one to three), either because of continued intolerance or a decision not to proceed with more alternatives. In conclusion, nearly two thirds of patients with initial problems with a particular statin are able to take an alternative statin without side effects. This supports the trial of different statins in intolerant patients.

Risk stratification is important in the assessment of cardiac patients enrolled in physical training programmes but is often based on inadequate information. Measuring blood B-type natriuretic peptide (BNP) level, a marker of left ventricular dysfunction, might improve risk assessment. In an observational study blood BNP levels were measured in 100 consecutive patients joining a cardiac rehabilitation programme following acute myocardial infarction. The results were compared with the clinical risk assessment – high, moderate or low. There was a significant correlation between risk category (high, moderate or low) and BNP level (r=0.41, p=0.001). A BNP level of 100 pg/L or more gave a sensitivity of 89% (95% confidence interval [CI] 0.69, 0.97) and a specificity of 61% (95% CI 0.57, 0.63) for predicting high-risk patients with a positive predictive value of 33% (95% CI 0.26, 0.36) and a negative predictive value of 96% (95% CI 0.89, 0.99). A BNP level of less than 100 pg/ml gave a sensitivity of 78% (95% CI 0.55, 0.91) and a specificity of 54% (95% CI 0.43, 0.64) for predicting low-risk patients with a positive predictive value of 27% (95% CI 0.17, 0.40) and a negative predictive value of 92% (95% CI 0.80, 0.97). In conclusion, BNP levels provide information that may improve the accuracy of risk assessment of cardiac rehabilitation patients particularly when other information is limited.