Cardiac abnormalities repolarization

Rudy, Y. (2006) Modelling and imaging cardiac repolarization abnormalities. Journal of Internal Medicine, 259, 91-106. 

These patients initial laboratory values showed acidosis, prolongation of the QRS complex and QTC interval, and right axis deviation. Appropriate treatment included hyperventilation, sedation, active cooling, and sodium bicarbonate, which led to correction of the blood pH and of the cardiac conduction disorders. The authors suggested that when intracellular pH is lowered, myocardial contractility is depressed as a result of reduced calcium availability. During acidosis, there are abnormalities of repolarization and depolarization, which potentiate dysrhythmias. 

In a series of ten paediatric castor bean ingestions, seven had transient ECG abnormalities, including QT interval prolongation (in five cases), intraventricular conduction disturbance and repolarization changes. The authors suggested that these changes were probably secondary to metabolic disturbances (Kaszds and Papp, 1960). It is possible that these abnormalities may have resulted from ricin-induced apoptosis of key elements of the cardiac conduction system. Such an effect of ricin has been noted in vivo in rats (Leek, 1989). 

Causes of abnormal cardiac repolarization in people with epilepsy, the putative contribution of antiepileptic drugs, and their potential role in the pathogenesis of sudden unexplained death in epilepsy have been reviewed [10 ]. 

Surges R, Taggart P, Sander JW, Walker MC. Too long or too short New insights into abnormal cardiac repolarization in people with chronic epilepsy and its potential role in sudden unexpected death. Epilepsia 2010 51(5) 738-44. 

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