No abstract

Background Abnormal dynamics of QT intervals in response to sympathetic nervous system stimulation are used to diagnose long‐QT syndrome (LQTS). We hypothesized that parasympathetic stimulation with cold‐water face immersion following exercise would influence QT dynamics in patients with LQTS type 3 (LQT3). Methods Study participants (n = 42; mean age = 11.2 years) comprised 20 genotyped LQTS children and 22 healthy children. The LQTS group was divided into LQT3 (n = 12) and non‐LQT3 (n = 8) subgroups. Provocative testing for assessing QT dynamics comprised a treadmill exercise followed by cold‐water face immersion. The QT intervals were automatically measured at rest and during exercise, recovery, and cold‐water face immersion. The QT/heart rate (HR) relationship was visualized by plotting beat‐to‐beat confluence of the data. Results The QT/HR slopes, determined by linear regression analysis, were steeper in the LQTS group than in the control group during exercise and immersion tests: −2.16 ± 0.63 versus −1.21 ± 0.28, P < 0.0001, and −2.02 ± 0.76 vs −0.75 ± 0.24, P < 0.0001, respectively. The LQT3 patients had steeper slopes in the immersion test than did non‐LQT3 and control individuals: −2.42 ± 0.52 vs −1.40 ± 0.65, P < 0.0001, and vs −0.75 ± 0.24, P < 0.0001. Conclusions The QT dynamics of LQT3 patients differ from those of other LQTS subtypes during the post‐exercise cold‐water face immersion test in this study. Abnormal QT dynamics during the parasympathetic provocative test are concordant with the fact that cardiac events occur when HRs are lower or during sleep in LQT3 patients.

Cornelia de Lange syndrome (CdLS) is a cohesinopathy caused by genetic variations. We present a female with SMC1A -associated CdLS with a novel SMC1A truncation mutation (p. Arg499Ter), transposition of the great arteries, and periodic intractable seizures from 40 months of age. A review of the literature revealed that a seizure-free period after birth of at least 15 months is required for these patients to be able to walk, irrespective of the epileptic course.

No abstract

Initial palliation with bPAB enables AoV diameter growth in some patients, improving the likelihood of conventional total repair adaptation rate, particularly for CoA or IAA type A.