Clinical articles

Heart failure is an increasingly common condition for which device therapy, including the advanced pacing technique cardiac resynchronisation therapy, is becoming an accepted treatment. In this review we discuss the rationale, evidence base, indications, limitations and implant technique of this maturing treatment modality and speculate on expansion of its role in the near future.

Despite the availability of an array of medical therapies for the treatment of heart failure, quality of life is often poor for the majority of patients, and the mortality remains high. In addition, treatment is regularly not well tolerated and this results in frequent hospital admissions for some patients. This article reviews the management and medical treatment of acute heart failure, focusing on the emerging role of levosimendan.
Levosimendan is currently licensed in 10 European countries (Simdax, Orion Pharma, Finland) for the treatment of acute heart failure. It is a new inotropic drug with a dual mechanism of action: sensitisation of the cardiac myofilament to calcium, thus enhancing cardiac contractility, and vasodilation of vascular smooth muscle. The published clinical studies so far have utilised intravenous levosimendan. However, the agent is also well absorbed orally, and phase two trials of its use in stable patients with less severe heart failure are underway.1

Cardiac rehabilitation offers physical, psychological and survival benefits for patients recovering from cardiac illness. This questionnaire survey of all known cardiac rehabilitation units in the UK provides data on how well the National Service Framework targets for cardiac rehabilitation are being met.

There is a widespread lack of awareness amongst the British public of the link between myocardial infarction and stroke, and about secondary prevention.

Atrial fibrillation (AF) is the commonest sustained
arrhythmia encountered in clinical practice.
Depending upon its time course, AF can be
classified into three categories: paroxysmal, persistent
and permanent.

The efficacy and safety of once- or twice-daily immediate-release (IR) fluvastatin 40 mg were compared with those of the extended-release (XL) formulation of fluvastatin 80 mg every night (qpm), which facilitates sustained drug delivery. Patients (n=442) with primary hypercholesterolaemia (Fredrickson types IIa and IIb) were randomised to the three treatment groups in the ratio 1:1:1. Active treatment was administered for 24 weeks, following a four-week placebo/dietary lead-in period.
At week 24, the mean reduction in low density lipoprotein cholesterol levels in patients treated with fluvastatin XL 80 mg every night (qpm) (-33.5%) was significantly greater than in the fluvastatin IR 40 mg every night (qpm) group (-23.2%; p<0.001), and similar to the reduction for patients treated with fluvastatin IR 40 mg twice-daily (bid) (-31.4%). Significant and dose-related alterations in other lipid variables were also apparent, particularly for high density lipoprotein cholesterol (10.2% increase) and apolipoprotein A1 and B levels (+11.5% and -24.2%, respectively) in the fluvastatin XL 80 mg qpm group compared with the fluvastatin IR 40 mg qpm group (all p<0.001). Mean triglyceride levels decreased by 14.6% in the fluvastatin XL 80 mg qpm group. Adverse events were generally mild, with no differences in frequency across the groups. Fluvastatin XL 80 mg qpm is a safe and effective lipid-lowering treatment for patients with type II hypercholesterolaemia.

One of the main targets of current research in cardiology is a diagnostic modality able not only to identify vulnerable atherosclerotic lesions but also to monitor the effects of therapeutic interventions on plaque composition. Most of the currently available techniques identify luminal diameter or stenosis, wall thickness or plaque volume, but are not capable of recognising vulnerable plaques that are prone to rupture. Thermography is a new technique which provides insight into the local inflammatory process within the atherosclerotic plaque. In this review we will present in detail the developments and the clinical implications of thermography in the human arterial system.

The prevalence of type 2 diabetes is set to double over the next 25 years, leading to substantial morbidity and mortality, particularly from macrovascular diabetic complications. Pre-diabetic dysglycaemia, characterised by impaired glucose tolerance (IGT) and/or impaired fasting glucose (IFG), is associated with an increased risk of developing both type 2 diabetes and cardiovascular disease. IGT and IFG appear well before type 2 diabetes is diagnosed, thereby presenting an opportunity for intervention to reduce the future burden of diabetes and cardiovascular disease. Intensive lifestyle interventions are effective in preventing or delaying diabetes but are difficult to sustain long term. Intervention trials with pharmacological agents, e.g. the Diabetes Prevention Program (DPP) with metformin, and the STOP-NIDDM study with acarbose, have demonstrated significant decreases in the risk of progression to type 2 diabetes in populations with IGT. Moreover, preliminary evidence with these agents supports a possible beneficial effect on cardiovascular outcomes.

Recent trials have broadened the evidence base for statin use. It has now been documented that these drugs are effective agents not only in the general at-risk population, but also in the primary and secondary prevention of coronary heart disease in type 2 diabetics and in the elderly. The Heart Protection Study demonstrated the benefits of statin therapy in diabetics free of vascular disease, regardless of initial low-density lipoprotein (LDL) cholesterol level. Age is no longer a barrier to treatment, as revealed in the Prospective Study of Pravastatin in the Elderly at Risk, a trial which found that even a relatively brief period of statin therapy in elderly patients can result in a 19% reduction in the risk of a coronary event.
Statins have the ability to lower the plasma concentration of all apoB-containing lipoproteins. This may help explain their clinical efficacy in diabetics who generally have unremarkable LDL-cholesterol levels. Most currently available statins are also able to induce a modest (5% to 10%) rise in high-density lipoprotein cholesterol, an effect that appears distinct from LDL lowering. This broadens their use to subjects with a variety of problems such as the metabolic syndrome and insulin resistance.
The success of large-scale trials in coronary heart disease contrasts with the abundant evidence of under-treatment, even in high-risk groups. Thus the greatest need, at present, is to close the gap between the principles and practice of coronary disease prevention.

Treatment to reduce blood pressure is effective in preventing and slowing the progression of the vascular complications of diabetes. Recent studies have suggested that use of antihypertensives that inhibit the renin-angiotensin system may have particular benefit in patients with type 2 diabetes in terms of cardiovascular and renal protection. Present practice is to use angiotensin-converting enzyme (ACE) inhibitors as first-line agents, with angiotensin II receptor antagonists (AIIAs) as back-up drugs in the event of side effects or intolerance. The findings of recent trials with AIIAs, however, suggest that they are an equivalent class of drugs to the ACE inhibitors from the point of view of renal profile and that their better side-effect profile could also make them suitable first-line drugs for patients with microalbuminuria and overt nephropathy.