Relation of CTG expansion and clinical variables to electrocardiogram conduction abnormalities and sudden death in patients with myotonic dystrophy

Age, conduction defects and restrictive lung disease independently predict cardiac events and death in myotonic dystrophy

“…Cardiac arrhythmias have been shown by several authors to have a broad correlation in severity with age [4,6,[21][22][23][24], muscular impairment [4,6,[23][24][25], male gender [6,21,22] and the extent of the molecular defect [14,21,26]. Consistently with these previous reports, we found that advancing age and MIRS were predictors of cardiac events in univariate Cox hazard analysis.…”

“…Consistently with these previous reports, we found that advancing age and MIRS were predictors of cardiac events in univariate Cox hazard analysis. However, we did not find any predictive value for male gender, for PaCO 2 , and for CTG repeat expansion, as reported by others [22]. The fact that age and muscular disability were predictors of cardiac events probably reflects, at least in part, the natural history of DM1 as well as disease severity at the time of investigation.…”

Usefulness of clinical and electrocardiographic data for predicting adverse cardiac events in patients with myotonic dystrophy

“…This was slightly higher than a previously reported rate of 0.1% to 0.2% per year for the general population (24), especially considering that the mean age in the present cohort was only 33 years. However, this rate remains quite low compared with the rates of 0.4% to 2% per year that can be extracted from other series (11,15,19,25). This can be explained by the fact that our cohort was derived from a systematic ascertainment and follow-up program among family members of patients diagnosed with DM1.…”

“…Although such a correlation between the extent of CTG repeats and the degree of cardiac involvement has been described in some series, others have shown conflicting results (9,17,18,25,(34)(35)(36)(37)(38)(39). Of note is the study by Lazarus et al (17); using precise invasive electrophysiological measurements, the study was unable to show such a relationship between conduction delays and the extent of CTG repeats.…”

Mortality in myotonic dystrophy patients in the area of prophylactic pacing devices

“…MD1 leads to multiple systemic complications, essentially related to muscular weakness, respiratory failure, cardiac arrhythmias and cardiac conduction disturbances. In the MD population, the age of death is lower than in the general population [4,5], and the frequency of sudden death is higher [3][4][5][6][7][8][9][10][11]. The 2002 study by Lazarus et al [12] demonstrated that a pacemaker (PM) should be implanted in patients with MD if their Hisventricle (HV) interval is ≥70 ms, even if they are asymptomatic, in order to protect them from the clinical consequences of profound bradycardia and to facilitate the diagnosis and management of frequent paroxysmal tachyarrhythmias.…”