Clinical articles

There are many advantages to bioabsorbable stents, including the potential to inhibit intimal hyperplasia by avoiding prolonged foreign body reaction and/or releasing antiproliferative drugs during degradation. The bioabsorbable polymer poly-l-lactic acid (PLLA) is used as a biodegradable coating of permanent metallic stents but can also be used to manufacture complete stents, at the expense of a greater recoil. Clinical, angiographic and intravascular ultrasound results at four years with the first stent tested (Igaki Tamai, Igaki, Japan) show patency rates similar to the rates expected with stainless steel stents and full reabsorption. Magnesium stents are another, perhaps more encouraging, development because they retain mechanical properties similar to conventional metallic stents. Full degradation of the magnesium alloy used to manufacture the Biotronik Lekton Magic stent requires 6–8 weeks. In man, initial clinical experience with this stent has been gained in patients with critical lower limb ischaemia. An ongoing study is testing its safety and efficacy in human coronary arteries.

Bivalirudin is a direct thrombin inhibitor that will be available in the UK in November 2004 as adjunctive anticoagulant therapy during percutaneous coronary intervention (PCI). Its mechanism of action offers potential advantages over heparin in terms of both efficacy and bleeding. Bivalirudin is convenient – ACT monitoring is unnecessary, infusion is only for the duration of the procedure, and half-life is short so that early sheath removal and ambulation are possible. Finally, bivalirudin may offer major cost savings over glycoprotein (GP) IIb/IIIa inhibitors. The REPLACE-2 trial demonstrated equivalent efficacy and reduced bleeding with bivalirudin alone versus heparin-plus-GP IIb/IIIa inhibition in 6,010 patients undergoing elective or urgent PCI (30-day MACE 7.6% vs. 7.1%, major bleeding 2.4% vs. 4.1%). Further trials are underway to evaluate the efficacy of bivalirudin during PCI for high-risk acute coronary syndromes (ACS) and acute myocardial infarction (AMI).
This paper considers when bivalirudin should be used in contemporary PCI. The ISAR-REACT study provides firm evidence that heparin alone is safe and effective for elective PCI in low-to-moderate risk patients (30 day MACE 4% heparin-alone vs. 4% abciximab). Patients with AMI or unstable ACS were not included in the REPLACE-2 trial and should continue to receive GP IIb/IIIa inhibitors until further data are available. Bivalirudin could be considered in patients at intermediate risk in whom GP IIb/IIIa inhibitors are currently widely used, including during complex elective PCI, elective PCI in diabetics, and in patients with stabilised or low-risk ACS. Bivalirudin will also have a specific role in patients at increased risk of bleeding and with heparin-induced thrombocytopaenia. Further data are required before more widespread adoption of bivalirudin can be recommended.

This study was set up to investigate the prognostic significance of different bands of troponin T in the diagnosis and management of patients presenting with suspected acute coronary syndrome without ST segment elevation. The study was a cohort study, set in a District General Hospital in the north west of England. The participants were 421 patients admitted with suspected acute coronary syndrome without ST segment elevation over a three-month period. Analysis was carried out depending on whether the level of troponin elevation was in a negative (< 0.03 µg/L), intermediate (0.03–0.1 µg/L) or positive (> 0.1 µg/L) band. The outcome was a composite of all-cause mortality or hospital admission due to non-fatal myocardial infarction at 30 days and 12 months.
Both intermediate and positive levels of elevated troponin increased the risk of all-cause mortality and non-fatal myocardial infarction at least two-fold, both at 30 days and 12 months (p<0.01). People over 50 were found to have a worse prognosis than younger patients at 12 months (p<0.05) but gender had no significant effect.
Patients with suspected acute coronary syndromes without ST segment elevation who have either intermediate or positive levels of troponin T show a substantial increase in adverse outcomes during short- and long-term follow-up. Further research is required on these bandings as new generations of troponin assays are developed with improved levels of precision.

We report a case of unprotected, ostial left main coronary artery disease successfully treated with a rapamycin-coated ‘Cypher’ stent in an 81-year-old woman who was declined for coronary artery bypass surgery because of significant co-morbidity.

Beta blockers are under-used in heart failure, despite their evident benefits. Here an educational and clinical support link between secondary and primary care was set up to mentor a nurse practitioner in heart failure management. A nurse-led heart failure clinic was established in a Hampshire general practice that enabled beta blocker therapy to be started safely and up-titrated successfully, without hospital referral.

In the second commentary on echocardiography in the community, general practitioner Ed Southall writes about the new British Society of Echocardiography accreditation process and his own experiences in running a community echocardiography service in South Devon.

Peripartum cardiomyopathy (PPCM) is characterised by the development of left ventricular (LV) dilatation and dysfunction during the last month of pregnancy, or the first five months of the post-partum period, in the absence of any pre-existing cardiac disease. PPCM is a rare but serious complication of pregnancy, with a variable outcome. Symptoms such as breathlessness and peripheral oedema are common in normal pregnancy and it is easy to misdiagnose PPCM in its early stages. The aetiology of the condition is uncertain.
Treatment options are similar to those for other forms of dilated cardiomyopathy. However, there are important considerations when treating women with PPCM as they may be pregnant or breast feeding. Close communication is required between cardiologists, obstetricians and neonatologists, not only for the treatment of the PPCM patient but also for protection of the baby. Women who decide to continue with further pregnancies should be carefully monitored.

Hypertension is the most important modifiable risk factor for stroke. The risk of stroke increases directly in proportion to systolic and diastolic blood pressure, and lowering blood pressure can reduce the risk of a first stroke by up to 40%. Current evidence suggests that it is safe and effective to lower blood pressure with an ACE inhibitor and a thiazide diuretic in patients with established cerebrovascular disease. The reduction in subsequent stroke is present both in hypertensive and non-hypertensive patients and is most likely to be related directly to the blood pressure- lowering effect. Ongoing studies will help to determine whether other classes of drugs, such as the angiotensin receptor blockers, are also safe and effective in the secondary prevention of stroke, and whether blood pressure should be lowered in the first few days after a major stroke.

The objectives of this analysis were to ascertain the population need for out-patient cardiac rehabilitation in England, to estimate the current level of provision and associated costs, to identify economies of scale in service provision and to investigate budgetary implications of extending provision.
Discharge statistics from the Hospital Episode Statistics database (HES) in England in the year 2000, and data from centres contributing to the British Association for Cardiac Rehabilitation (BACR) survey were analysed. A short follow-up questionnaire was sent to respondents of the BACR survey.
The main outcome measures were: the number of patients eligible for cardiac rehabilitation; the percentage referred, joining and completing programmes; health service costs associated with current levels of provision; elasticity of costs; and costs associated with expanding services. Using an inclusive definition of need, about 267,000 people required cardiac rehabilitation in England in the year 2000. This figure fell to 100,000 if services were restricted to those aged below 75 years with acute myocardial infarction, unstable angina or following revascularisation. Health service costs per patient completing a programme were £354 (staff) and £486 (total). Out-patient cardiac rehabilitation represented a NHS cost of approximately £12.5–19.0 million per annum. A 1% increase in patients completing a programme is estimated to lead to a 0.25% fall in the staff cost per patient. A budget increase of 630% would be necessary to treat all eligible patients using moderate staffing configurations, which would fall to 170% if only those aged below 75 years with restricted diagnoses were to be treated.
We conclude that a substantial proportion of the population need for cardiac rehabilitation goes unmet and that achievement of current targets for provision is likely to require considerable additional resources. Reconfiguration of service provision towards less complex services would enable more patients to be treated. Current information systems in cardiac rehabilitation services are inadequate to provide indicators of performance and monitoring.

Integrated Care Pathways (ICPs) are one way of implementing protocol-based care. Healthcare professionals need to draft and implement ICPs in order to meet clinical governance targets. In a two-day workshop ‘Integrated healthcare delivery – let’s get practical’, 27 multidisciplinary delegates from four NHS Modernisation Teams progressed ICPs in the areas of stroke, post-myocardial infarction and heart failure. Good ICPs should include a clear assessment procedure for the clinical condition, consultation with all care providers, guidelines or best available clinical evidence, patient education and an audit tool.