Ventricular arrhythmias and acute left ventricular dysfunction as a primary and life-threatening manifestation of a mitochondrial crisis: A novel management strategy

Abstract

Mitochondrial disorders are genetic diseases that result in a deficiency of energy metabolism (ATP production). A "mitochondrial crisis" can occur in the setting of infection, dehydration, or physiologic stress. The hallmark of a mitochondrial crisis is failure of multiple individual organ systems. The mortality of mitochondrial crisis is high and therapy is supportive but involves a specific strategy of hydration with dextrose-containing IV fluids, avoidance of many medications known to worsen mitochondrial function, and limitations of oxygenation as this can promote free radical production. We report a case of a patient with known mitochondrial disease that presented with a mitochondrial crisis with prominent and life-threatening cardiac manifestations including long QT, ventricular arrhythmias, and acute left ventricular systolic dysfunction in addition to rhabdomyolysis, lactic acidosis, and an acute kidney injury. This patient was managed successfully with a specifically tailored supportive strategy, a high-dose metabolic cocktail, permissive hypoxia, and low-protein diet. At 10 weeks post discharge all electrocardiographic abnormalities resolved and ventricular recovery has been observed. Given the increased survival of this population of patients into adulthood it is important that these adjunctive therapeutic strategies require consideration by clinicians treating this group of patients.

Keywords: Arrhythmia; Cardiomyopathy; Clinical management; Mitochondrial crisis.

Fig. 1

Electrocardiographic changes at baseline, during the mitochondrial crisis, and in follow up after resolution of the crisis state.

Fig. 2

M-mode images from echocardiography performed at various time points during the course of the illness. Baseline study was performed two years before the patient developed the mitochondrial crisis (no parasternal short-axis view was available for comparison). The Day 2 and Day 8 echocardiograms show progressive deterioration of left ventricular systolic function. The final study, performed 3 months into the patient's clinical recovery, demonstrates improvement back to baseline.