Cardiac Biomarkers in Preeclampsia: Prediction of Disease and the Risk of Future Cardiovascular Events in Survivors

Preeclampsia is a disease that is strongly linked with the risk of stroke and other cardiovascular disease. This is a condition with greater prevalence in the Low and middle income countries of the world especially sub-Saharan Africa, where the morbidity and mortality is reportedly higher. Larger numbers of survivors are expected with the rising global gains in maternal mortality reduction associated with preeclampsia. These cardiovascular diseases myocardial ischemia, myocardial infarction and stroke are major causes of sudden death because the precursor conditions; atherosclerosis and hypertension are largely asymptomatic. There are established biomarkers for these conditions which can be used as screening tools. The low utilization of routine health care check and the asymptomatic nature of these events increase the risk of sudden premature death from these conditions. The postnatal period offers a good opportunity for screening for these events to detect women at risk and offer early preventive care.

Preeclampsia is essentially a disease of the trophoblast, it has also been shown to be associated with oxidative stress, a phenomenon, which increases the levels of LDL cholesterol peroxidation, leading to its increased uptake by macrophages, resulting in foam cell formation and atherosclerosis. Preeclampsia is also associated with inflammatory changes that alter vascular integrity - an effect which may persist beyond pregnancy, resulting in atherosclerosis which predisposes to myocardial ischemia, myocardial infarction and stroke.

These changes in the vasculature are asymptomatic and unless hypertension is detected early and vasoprotective or antithrombotic treatment commenced, sudden death may occur from stroke or acute myocardial infarction.

Hypertensive heart disease refers to heart conditions that result from the effect of hypertension. The heart in this instance now works under a higher pressure resulting in the hypertrophy of cardiac muscle, thickening of the cardiac arterial vasculature (leading to coronary arterial disease) and increased risk of myocardial ischemia and infarction. The resulting cardiac muscle dysfunction leads to increasing levels of pro-inflammatory cytokines, which can be detected in the blood stream and whose levels may correlate with the presence and severity of the disease condition. Hypertension has similar effects on the cerebral vasculature, where it can cause vessel rupture resulting in life-threatening intracranial haemorrhage. The vessels under the influence of long standing hypertension may undergo hypertrophy leading to thickening of the vessel wall with narrowing of lumen and then cerebral ischemia, infarction and stroke.

There is a significant reduction in the risk of fatal and non-fatal stroke if hypertension is detected early and effectively controlled with antihypertensive drugs. This preventive strategy has been shown to be of more benefit when commenced at a younger age and especially in women of the black race who are at higher risk and would benefit more.