Summary:
Eccentric atherogenic plaques which cause only insignificant narrowing of the diameter of coro-
nary arteries are the cause of 60 - 80 % of all acute coronary syndromes. The plaque becomes
unstable (vulnerable) due to cytokines released by macrophages in the lipid rich core. Weakening
of the fibrous capsule of the core then leads to rupture of the plaque and subsequently to intraco-
ronary thrombosis with a wide spectrum of ischaemia or even necrosis of the myocardium. Secon-
dary preventive studies (4S, LIPID, CARE), morphological non-mortality studies (e.g. AVERT,
REGRESS, LCAS) and primary preventive studies (WOSCOPS, AFCAPS/TexCAPS) revealed that
statins reduce sifgnificantly, as compared with placebo, total and LDL-cholesterol by 20 – 35 %and
lead in subsequent years to a significant decline of the relative risk of the general and coronary
mortality and morbidiy by 20 - 40 %. They prevent progression and may lead to regression of
coronary sclerosis. They do not act by mere reduction of the cholesterol level but also by their
extralipid effects which stabilize the plaque. 80 % of patients with coronary syndrome have cho-
lesterol levels between 6.0 and 7.5 mmol/l, similarly as ca 40 % of healthy middle aged persons. The
difference is in the risk caused either by the presence of ischaemic heart disease or in healthy
subjects by the cumulation of several coronary risk factors. A special risk group are the remai-
ning 20 % patients. They include subjects with a cholesterol level above 8 mmol/l who must be
treated more aggressively, similarly as patients after a venous aortocoronary bypass. Subjects
with slightly elevated LDL-cholesterol values but high triacylglycerol levels and lower HDL-cho-
lesterol levels have also an atherogenic risk. This applies not only to postmenopausal women,
elderly people, obese and diabetic subjects, hypertensive subjects with insulin resistance but also
to young subjects. In the latter reduction of triacylglycerols is indicated. In coronary patients
a combination of statins and fibrates may be used. Basic hypolipidaemic treatment for reduction
of the atherothrombotic risk are statins. Despite statin treatment the prospective mortality and
morbidity of coronary patients is still high and it is necessary to make an effort to achieve target
lipid levels. Recent studies provide new findings, further progress and stricter therapy are forese-
en.
Key words:
Acute coronary syndrome - Vulnerable plaque - Statins - Fibrates.
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