QTc interval in patients with multiple sclerosis: an inference from the insula of Reil?

BACKGROUND AND PURPOSE: The aim of this study was to investigate the correlation between the duration of the QTc interval and the brain lesion load at the level of the structures involved in superior autonomic control (insula, cingulate cortex and amygdala-hippocampus) in multiple sclerosis (MS) patients. METHODS: Thirty-one consecutive patients with relapsing-remitting MS were recruited. The QT interval was measured manually in all 12 leads by a single blinded observer, with the longest QT value adjusted for heart rate by using the Bazett's formula. All patients performed a brain magnetic resonance imaging (MRI) scan including three-dimensional double inversion recovery and three volumetric fast-field echo sequences. The following MRI measures were obtained: (i) global and regional cortical thickness (CTh); (ii) white matter lesion load volume; (iii) cortical damage blindly assessed by a trained observer who assigned, on the basis of the number of cortical lesions, a score from 0 to 5 for each of the brain areas analysed. RESULTS: In all, 16% of the patients had an increased QTc interval. The QTc interval was correlated with disease duration, cortical insular lesion volume and grey matter lesion volume in the three examined areas and inversely correlated with global and insular CTh. CONCLUSIONS: An increased QTc interval in patients with MS may have a cerebral origin possibly driven by involvement of the insular cortex. With the recent introduction in clinical practice of treatments with potential cardiac effects such as fingolimod, the recognition of a long QTc interval could be clinically crucial and should encourage appropriate electrocardiographic monitoring in order to prevent the risk of malignant ventricular pro-arrhythmia and iatrogenic sudden death.

Isolated noncompaction of the myocardium: an exceedingly rare cardiomyopathy. A case report.

Isolated noncompaction of the left ventricular myocardium is a rare cardiac disorder due to an arrest in myocardial morphogenesis. It is characterized by prominent and excessive trabeculation in a ventricular wall segment, with deep intertrabecular spaces perfused from the ventricular cavity. Echocardiographic findings are important clues for the diagnosis. Clinical symptoms include signs of left ventricular systolic dysfunction even to the point of heart failure, ventricular arrhythmias, and embolic events. We describe an adult case in whom the only clinical symptoms were life-threatening ventricular arrhythmias. Transthoracic echocardiography did not contribute to the diagnosis, which was made thanks to left ventricular contrast angiography. Electrophysiological testing induced a fast monomorphic sustained ventricular tachycardia, with hemodynamic impairment, that was refractory to pharmacological treatment, and for this reason a permanent cardioverter-defibrillator was implanted. A subsequently performed transesophageal echocardiographic examination showed a localized, regional increase in left ventricular wall thickness and degree of trabeculation. The causes and electrophysiological mechanisms of arrhythmias in noncompaction are still unknown: grossly irregular branching and connecting of myocardial fascicles in the noncompacted segments, isometric contraction with increased wall stress, and localized coronary perfusion impairment can all induce disorganized or delayed activation and increase the potential for arrhythmias. This is the first reported case of noncompaction in which an implantable defibrillator was used to control life-threatening arrhythmias.