Fatal short-coupled torsade de pointes in a patient with primary oxalosis

Excerpt

A 24-year-old man suffering from primitive type 1 hyperoxaluria with end-stage renal failure underwent double kidney–liver transplantation. Two weeks later, multiple episodes of short-coupled torsade de pointes (Sc-TdP) occurred, degenerating into ventricular fibrillation, requiring several electric shocks. Episodes of TdP were always induced by ventricular premature beats with short coupling interval (Fig. 1a). Intercritical electrocardiogram, and serum levels of calcium, potassium, magnesium, and oxalate were normal. Echocardiography showed severe hypertrophy with typical granular sparkling of myocardial walls (Fig. 1b). Isoproterenol, β-blockers, amiodarone, and lidocaine were successively tested by continuous infusion without success. Enteral verapamil administration led to transient suppression of arrhythmia. Intensive hemodialysis was performed daily to reduce accumulation of oxalate crystals in the myocardium. However, the patient died 2 weeks later after new electrical storm. Primary oxalosis is a metabolic disease which leads to accumulation of calcium oxalate crystals in tissues such as liver, kidney, and heart (Fig. 1c). Accumulation of calcium in intracellular cardiomyocyte spaces later gave rise to afterdepolarization causing Sc-TdP. Treatment by verapamil at high doses has been proposed, as well as isoproterenol infusion and rapid atrial pacing to treat electrical storm [1].

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