Magnesium: A Blood Pressure Modulator

Abstract

Objective: Magnesium plays an important role at cardiac level as it affects myocardial metabolism, calcium homeostasis, tone and vascular peripherals resistances. Low serum magnesium levels are associated with an increased risk of coronary artery disease and arteriosclerosis. Design and method: We propose a case of a 57 y.o. male, non smoker hypertensive patient treated with sartans and potassium kanreonate. In the past medical history: biopsy-proven chronic gastropathy and revascularized ischemic heart disease. He arrived in ER for dizziness, nausea and severe hypertension. The patient presented psychomotor agitation, muscle pain and paraesthesia. Blood tests revealed hypocalcaemia, hypokalaemia, hypomagnesaemia. Electrolyte supplementation was performed with a significant improvement of clinical picture. Two months later, the patient is back to the ER for hypertensive crisis. So he is hospitalized in the Nephrology Unit to be studied. Results: Blood tests revealed: haemoglobin: 12.2 g/dl, serum creatinine: 0.6 mg/dL, serum potassium levels: 4 mEq/L, serum calcium levels: 9.1 mg/dL, and serum magnesium levels: 1.2 mg/dL. Abdominal echo resulted negative for acute lesions and the renal artery Doppler did not show stenosis. Plasma and urinary catecholamines were normal. During the hospitalization, due to severe symptoms, iv supplementation with Magnesium sulphate (1 fl IV/week) was performed with an increased of serum magnesium levels and progressive hemodynamic compensation. On the contrary, serum sodium and potassium levels and magnesuria were normal, rather than increased. The patient was discharged after performing genetic investigations for possible tubulopathy (in progress) and with a programmed outpatient follow-up in which we observed the normalization of blood pressure values with the same antihypertensive therapy, but with magnesium values rather normal. Conclusions: Blood pressure control is affected by serum magnesium levels .