, patients with 2 pathogenic variants had longer corrected QT (QTc) intervals and were more likely to experience cardiac events and cardiac arrest than patients with single variants (25).
Be aware that an acquired LQTS
may mask an underlying congenital LQTS
The results show promise for using in vitro iPSC techniques in the development of individualized drug therapies for patients with LQTS
and other channelopathies.
This includes a comprehensive clinical and genetic evaluation; a consultation with LQTS
experts as needed; extensive counseling regarding individual risks and athletic guidelines; tailored therapy (beta-blockers, left cardiac sympathetic denervation, and/or an ICD); education regarding appropriate hydration and electrolyte replenishment; minimizing elevations of core body temperature; and avoidance of QT drugs, the authors noted.
In the study, the records of 353 LQTS
patients ages 6 to 40 who were evaluated at Mayo Clinic between July 2000 and November 2010 were reviewed to determine which patients chose to continue athletic participation after LQTS
diagnosis and LQTS
Common presentations of LQTS
include palpitations, presyncope, syncope, or cardiac arrest.
A total of 21 studies were excluded because of the pre-test indication of "possible LQTS
" based on either baseline electrocardiogram or on a family history of syncope, sudden death, or known LQTS
The first study identified differential conditions and cellular mechanisms that can trigger SCD when LQTS
is a factor, and the second study, for the first time, directly linked sex hormones and the incidence of arrhythmia and SCD.
S111, S111 (2010) (finding that the enforcement of gene patents before the development of a commercial test led at least one of two previous providers of genetic testing for long QT syndrome (LQTS
) to cease testing, a decision that "probably had a small but tangible negative effect on patient access to genetic testing for LQTS
between 2002 and 2004").
For example, South and Southeast Asians suffer from various iterations of arrhythmogenic sudden cardiac death (Pokkuri, Bangungut, Sudden Unexpected Nocturnal Death Syndrome)  which may or may not all be variations of LQTS
or Brugada Syndrome , all thought to be genetic in nature.
1 This is a descriptive report of eight children diagnosed to have congenital LQTS
from 2000 to 2007 (Table 1), in Sarawak General Hospital, Kuching, Sarawak, Malaysia, the main tertiary referral hospital for Sarawak.
Many acquired factors may lead to QT prolongation ranging from drug effects, electrolyte abnormalities and ischemia; however, the diagnosis of LQTS
must be made even in the absence of these factors.