CARDIOVASCULAR JOURNAL OF AFRICA • Volume 33, No 2, March/April 2022 AFRICA 71 A study by Ding et al.50 analysed the association between interleukin-6 and heart function in a pre-eclampsia model of pregnant rats. The administration of interleukin-6 further worsened the tissue Doppler mitral systolic peak velocity (Sm) and early diastolic (Ea) peak velocities in the rats with reduced uterine perfusion pressure, and increased the medial E/Ea ratio. It also increased serum concentrations of cardiac troponin I, the MB fraction of creatinine phosphokinase (CK), myoglobin and brain natriuretic peptide (BNP). The authors concluded that interleukin-6 is complicit in the myocardial damage occurring in such pregnancies. They further proved that inhibiting interleukin-6 with tocilizumab improved the E/Ea ratio and lowered the expression of BNP and CK-MB. We identified several studies assessing the relationship between interleukin-6 levels and echocardiographic parameters in non-pregnant populations. In a study by Pauli et al.51 enrolling early-onset coronary artery disease patients and healthy controls, interleukin-6 had a negative correlation with echographic measurements of the diameter of the ascending aorta, shortening fraction of the LV and EDD of the RV. In a different study, increased interleukin-6 levels were related to the presence of LV diastolic dysfunction, defined as mitral E/e′ mean ratio ≥ 15 in patients indicated for coronary angiography.52 In patients with systemic atherosclerosis, it had negative correlations with medial, lateral and mean e′ wave of the mitral annulus and a positive correlation with the mitral inflow E/e′ ratio.53 In a cardiac magnetic resonance study its levels correlated inversely and strongly with the regional LV function.54 Our study proves that the exaggerated inflammatory activation during hypertensive disorders of pregnancy, as expressed by interleukin-6 levels, is additionally associated with more pronounced changes in cardiac structure and function in pre-eclampsia. On one hand, we believe this link could be interpreted as proof of the role of hypertensive disorders of pregnancy, and especially pre-eclampsia, as a risk factor for future adverse cardiac outcomes. Additionally, if implemented in clinical practice, measuring higher interleukin-6 levels could be interpreted as a need for stricter follow up and control of the individual risk factors of those women in order to improve their cardiovascular profile. It is not without merit to identify biomarkers that could be used as surrogates of cardiac changes, as this could greatly influence post-pregnancy care for women. Conclusions Serum interleukin-6 levels were significantly elevated in women with both gestational hypertension and pre-eclampsia compared to healthy pregnant women. When analysed in subgroups the difference remained significant for severe and early forms of both conditions, as well as the mild form of pre-eclampsia. In pre-eclampsia, but not in gestational hypertension, higher levels significantly correllated with echocardiographic changes, indicative of chamber remodelling and dysfunction. 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