2003, Volume 10, Issue 02, pages 77-160

The British Journal of Cardiology begins a series of articles exploring the work of the Coronary Heart Disease Collaborative. This editorial gives a brief introduction to its origins, aims and philosophy for readers not yet involved in its activities.

Over the last decade, technical improvements have made off-pump coronary artery bypass (OPCAB) surgery a routine procedure. Exposure and positioning of the three main coronary targets with minimal haemodynamic deterioration has been achieved with a combination of pericardial retraction sutures, the Trendelenburg manoeuvre, and rotation of the operating table.1-3 Intracoronary shunts have been introduced to prevent snaring-related injury of the coronary vessels and to allow myocardial perfusion during the construction of the anastomoses.

Interventions to aid smoking cessation post-myocardial infarction Celine Adams Smoking kills. Almost a fifth (19%) of all coronary heart disease deaths in the UK are attributable to smoking.1 Many of these could be prevented. Smoking cessation significantly decreases mortality and – in the setting of myocardial infarction – this reduction is estimated at 35%.2 Smoking cessation is also cost effective with interventions in the UK ranging from £212 to £873 per life year gained.3 But in the setting of unstable cardiovascular disease, safe and efficacious methods of helping patients to stop smoking are yet to be demonstrated.

Achieving good glycaemic control is an important part of the treatment strategy to minimise vascular complications in diabetes. An expanding range of differently acting oral antidiabetic agents provides new choices for type 2 patients. This review considers the attributes and limitations of these agents, and their positioning in the treatment process.

My approach to assessing CHD risk

There are now well-recognised guidelines which state that when reducing someone’s risk of cardiovascular disease the decision to start medication depends on the patient’s absolute risk of coronary heart disease, as opposed to their relative risk, which should be determined using multiple risk factors. More than 29 cardiovascular risk tools are available to calculate a patient’s absolute risk of cardiovascular disease. Choosing which risk tool to use can be difficult. This article gives a description of the differences between cardiovascular risk tools. It also discusses some of the problems and benefits of risk tools in general and examines the differences between absolute and relative risk.

Scotland has one of the highest mortality rates for ischaemic heart disease (IHD) in the world, accounting for one quarter of all deaths. Much evidence demonstrates aggressive management of risk factors can make a significant difference to this high morbidity and mortality. Current evidence suggests that secondary prevention of IHD is currently not carried out well in primary care in the UK. Our practice set out to see if this could be improved by using computer records. Over the course of four years more than 80% of IHD patients are now on aspirin, almost 90% have blood pressure recorded annually (average 130/74 mmHg), 82% are non-smokers, 84% have an annual cholesterol check, 65% have a cholesterol < 5 mmol/L, 56% are on a cholesterol-lowering drug (average cholesterol is 4.76 mmol/L), 61% are on cardioprotective drugs, and there was one acute infarct. We suggest that secondary prevention can be improved at a practice level with a good recording system, and a motivated primary care team.

Angina pectoris occurs in 30–40% of patients with aortic stenosis, despite a normal coronary circulation. This along with syncope, classically occurs during exercise. There are a number of suggested pathophysiological mechanisms for these symptoms, all of which lead to an imbalance between myocardial oxygen supply and demand. We report an 81-year-old patient who had several episodes of chest pain occurring at rest, leading to syncope resulting in electro-mechanical disassociation (EMD) cardiac arrest. The electrocardiogram (ECG) during these episodes showed profound ST depression, leading to the hypothesis that the underlying pathophysiology was due to myocardial ischaemia caused by the aortic stenosis alone.

Sibutramine is one of two anti-obesity agents approved by the National Institute of Clinical Excellence. It inhibits the re-uptake of noradrenaline and serotonin in the brain. By enhancing the sensation of satiety after a meal and reducing the fall in basal metabolic rate which usually occurs during weight loss, sibutramine is a useful aid to achieving weight loss and weight maintenance. Randomised controlled trials have shown that sibutramine 10 mg/day, in combination with diet and exercise, produces and maintains a dose-related weight loss of 5–10% in the majority of obese patients studied. This is accompanied by a range of important health benefits, including improvements in cholesterol and triglyceride levels. Adverse publicity led to the European Commission's Committee for Proprietary Medicinal Products recently carrying out an in-depth investigation into the use of sibutramine in over 12,000 patients across Europe. Its findings support the use of sibutramine in obesity management, with no causal link found between the use of the drug and mortality. No change has been made to the Summary Product of Characteristics regarding the cardiovascular safety of sibutramine and the drug has been re-instated for use in Italy. Prescribers should be aware of the cautions surrounding sibutramine use. While it is not advisable for those with a history of coronary heart disease or cardiac arrhythmias, published data reveal that most patients on sibutramine experience a drop in blood pressure and it may be used safely in patients with controlled hypertension. A small number of patients treated may show increases in blood pressure, particularly those who appear to be non-responders. Regular blood pressure monitoring is therefore advised.

Almost a half of all myocardial infarctions occur in those over 70 years of age and this is projected to rise further as the number of older patients in the total population increases. Following myocardial infarction, complications are more common in the older patient and the mortality outlook is much worse in those aged over 75 years. Guidelines generally favour the administration of thrombolysis post-myocardial infarction to older patients, although there is a lack of randomised clinical trials with thrombolysis in this group. Observational data, however, suggest that there is a significantly increased risk of mortality in patients aged over 75 years and this means the elderly are less likely to receive thrombolytic therapy, even when no contraindications are present. Randomised trials have shown that percutaneous coronary intervention is associated with a better outcome in the older patient. With the advances in antiplatelet therapy and the advent of intracoronary stents, this outcome is expected to improve further. The article also discusses therapeutic options in secondary prevention.

Clinical and epidemiological studies suggest elevated levels of total plasma homocysteine (> 15 µmol/L) are associated with an increased risk of cardiovascular disease, independent of other known risk factors. This review outlines the causes of hyperhomocysteinaemia, current evidence of a positive association with cardiovascular disease, and how such findings may have important implications for future assessments of risk and nutritional recommendations, particularly for those with a previous or family history of cardiovascular disease.

Modest elevations in plasma homocysteine from either genetic or acquired causes appear to relate to cardiovascular disease on the basis of strong epidemiological evidence. We know that homocysteine can be lowered with varying doses of folic acid, with or without vitamins B6 and B12, although we do not yet know the potential cardiovascular benefit of vitamin supplementation in these subjects. Several multicentre interventional trials are underway to address this question and, until these are complete, we recommend a healthy diet high in folate replete foodstuffs. We also recommend oral folic acid supplements in some subjects with cardiovascular disease and high homocysteine, mindful that definitive evidence of benefit is lacking.

The evidence for ambulatory blood pressure measurement (ABPM) as an indispensable investigation in clinical practice is now overwhelming. For years the argument against ABPM has been based on a lack of evidence showing the technique was superior to conventional measurement in predicting outcome. There is now ample evidence from longitudinal studies that ABPM is a much stronger predictor of cardiovascular morbidity and mortality than conventional measurement.1 Moreover, though the relevance of nocturnal hypertension has been a controversial topic, recent evidence has shown that a non-dipping nocturnal pattern is a strong independent risk for cardiovascular mortality.

The study aim was to compare clinic and 24-hour ambulatory blood pressure monitoring, and to determine the influence of the latter on the management of a group of patients with variable or uncontrolled blood pressure. A retrospective data analysis was carried out on patients selected from out-patient clinics at New Cross Hospital. One hundred and seventy-one patients with uncontrolled or variable blood pressure underwent 24-hour ambulatory blood pressure monitoring and 153 results were analysed. Following ambulatory blood pressure monitoring, 56% of the patients had their treatment regimens either decreased, unaltered or did not require antihypertensive therapy. The study found 24-hour ambulatory blood pressure monitoring helps in the assessment of overall 24-hour blood pressure control of patients and may also help in the better management of difficult groups of patients.