Cardiac Dysrhythmias and Neurological Dysregulation: Manifestations of Profound Hypomagnesemia

Abstract

Magnesium is the second most common intracellular cation and serves as an important metabolic cofactor to over 300 enzymatic reactions throughout the human body. Among its various roles, magnesium modulates calcium entry and release from sarcoplasmic reticulum and regulates ATP pumps in myocytes and neurons, thereby regulating cardiac and neuronal excitability. Therefore, deficiency of this essential mineral may result in serious cardiovascular and neurologic derangements. In this case, we present the clinical course of a 76-year-old woman who presented with marked cardiac and neurological signs and symptoms which developed as a result of severe hypomagnesemia. The patient promptly responded to magnesium replacement once the diagnosis was established. We herein discuss the clinical presentation, pathophysiology, diagnosis, and management of severe hypomagnesemia and emphasize the implications of magnesium deficiency in the cardiovascular and central nervous systems. Furthermore, this case highlights the importance of having high vigilance for hypomagnesemia in the appropriate clinical setting.

Vestibular Disorders after Kidney Transplantation: Focus on the Pathophysiological Mechanisms Underlying the Vertical Nystagmus Associated with Tacrolimus-Related Hypomagnesamia

“…Hypomagnesemia may be present together with nonspecific symptoms such as anorexia and nausea, cardiological abnormalities such as arrhythmias, and with neurological symptoms and signs [ 9 , 10 ]. A further, often under-recognized, clinical manifestation of Mg depletion is vertical, usually down-beating, ny [ 11 , 12 , 13 ].…”

Normo-Calcemic Tetany in a Patient with Hypokalemic Periodic Paralysis of Sjogren’s Syndrome: Neuromuscular Excitability Secondary to the ‘Forgotten Cation’

“…Our patient had both of these electrolyte and acid-base abnormalities. Hypomagnesemia has been shown to cause multiple neurological abnormalities, including tetany (8).…”

Paroxysmal Tremor and Vertical Nystagmus Associated with Hypomagnesemia

“…On the one hand, hypermagnesemia can be life‐threatening, but it is almost exclusively observed in patients with substantially impaired kidney function and magnesium intake through supplements or other magnesium‐based treatments (eg, antacids). On the other hand, hypomagnesemia may present with non‐specific symptoms such as anorexia and nausea, cardiological abnormalities (including arrhythmia, ECG changes, and even sudden cardiac death), as well as neurological symptoms and signs, 6 including those resulting from neuromuscular hyperexcitability (Chvostek and Trousseau signs, tremors, fasciculation, and tetany), paresthesia, apathy, confusion, encephalopathy, epilepsy, opsoclonus, and ataxia 7 . Although, the underlying pathophysiology is unknown, vertical nystagmus, usually downbeat, has been described to be a typical manifestation of magnesium depletion 5,8–10 …”