Increased QT variability in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.
OBJECTIVE
Although sudden death (SD) accounts for numerous cases of premature mortality in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), the risk factors responsible for this dramatic event remain unclear. We sought possible differences in the QT variability index (QTVI) -- a well-known index of temporal dispersion in myocardial repolarization strongly associated with the risk of SD -- between a group of patients with CADASIL and healthy controls.


METHODS
A total of 13 patients with CADASIL and 13 healthy volunteers underwent a 5-min electrocardiogram recording to calculate the QTVI. All the patients also underwent a clinical assessment, including functional status by Rankin score, and a magnetic resonance imaging (MRI) brain scan for quantitative analysis of T2-weighted (T2-W) and T1-weighted (T1-W) lesion volume (LV).


RESULTS
Short-term QT-interval analysis showed significantly higher QTVI (P = 0.029) in patients than in controls. In patients, notwithstanding the limitations of the small sample size, QTVI also well correlated with T1-W LV (r = 0.747, P = 0.003) and T2-W LV (r = 0.731, P = 0.005).


CONCLUSIONS
Because patients with CADASIL have increased temporal cardiac repolarization variability as assessed by QTVI, this mechanism could underlie these patients' risk of SD. Whether this easily assessed, non-invasive marker could be used to stratify the risk of malignant ventricular arrhythmias in patients with CADASIL and, possibly, to guide their therapeutic management warrants confirmation from larger prospective studies.
Piccirillo
G
G
Dipartimento di Scienze dell'Invecchiamento, Policlinico Umberto I, Università La Sapienza, Rome, Italy. gianfranco.piccirillo@uniroma1.it
Magrì
D
D
Mitra
M
M
Rufa
A
A
Zicari
E
E
Stromillo
M L
ML
De Stefano
N
N
Dotti
M T
MT
D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D001921:Brain / Q000098:blood supply / Q000473:pathology / Q000503:physiopathology; D046589:CADASIL / Q000150:complications*; D002536:Cerebral Arteries / Q000473:pathology; D016757:Death, Sudden, Cardiac / Q000209:etiology*; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology; D006339:Heart Rate / Q000502:physiology; D006352:Heart Ventricles / Q000294:innervation / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011237:Predictive Value of Tests