Tinker, tailor: Foretelling the future in long QT syndrome

Abstract

Tinker Tailor is a counting game, nursery rhyme, and fortune-telling song attributed to the playwright and poet William Congreve that is traditionally recited by young irls to determine their fate. Clinicians and investigators tinker” with patient data to determine best treatment stratgies, and much of the evidence we use to “tailor” our anagement is gathered one patient at a time through disase registries. Despite these efforts, prediction of patient utcome remains imperfect. The current study attempts to mprove prediction through assessment of the location of isease-causing mutations (along with clinical variables) in he long QT (LQT) -2 population. Cesarino Romano and colleagues first clinically described the common form of LQT syndrome in 1963. Owen Conor Ward also recognized the syndrome, and its “conpicuous improvement” with beta-blocker therapy. Addiional therapies included left stellateganglionectomy, pacing, and defibrillators, but beta-blockade remains the mainstay of treatment. Both long QT probands and their presymptomatic family members can reduce their event rate through beta-blocker therapy. In 1994, Jiang and colleagues mapped nine families ith hereditary QT prolongation to the long arm of chroosome 7 and three families to 3p21–24, in addition to amilies already linked to 11p15.5. They noted that “the phenotypes of patients with different forms of LQT are surprisingly similar” but that “[w]ith the benefit of these genotypic data we may now find subtle phenotypic difference.” The subsequent year, Curran and colleagues idenified mutations of KCNH2 (then called HERG) that encode he IKr potassium channel and cause LQT2 syndrome. ausse and colleagues described the unique electrocariogram phenotype of LQT2, and Keating suggested that identifying the underlying molecular mechanism of each LQT syndrome may guide therapy.