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Korjattu QT-aika

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Artikkeli tarkastettu 1.8.2025 • Päivitetty kokonaisuudessaan

QT-aika tulee mitata EKG:sta, eikä käyttää koneen ilmoittamaa arvoa. Mittaus tehdään Q-aallon alusta T-aallon loppuun. Jos T-aallon loppua on vaikea erottaa, mitataan aika T-aallon laskevan osan tangentin ja perusviivan leikkauspisteeseen. R-R-väli mitataan samasta lyönnistä kuin QT-aika. Katso tarvittaessa Lääkärin käsikirjan artikkelista «Pitkä QT -oireyhtymä (LQTS)»1 ohjeet QT-ajan mittaamiseen. Lomake laskee QTc-ajan käyttäen Bazettin kaavaa: QTc = QT/(R-R)½.

Taulukko 1. Korjattu QT-aika *
1–15-vuotiaat Miehet Naiset
* Lähde: Mäkijärvi M, Parikka H, Raatikainen P. QT-aika. EKG-tietokanta [online]. Helsinki: Kustannus Oy Duodecim [päivitetty 1.1.2005] . Saatavilla Internetissä (vaatii käyttäjätunnuksen): «QT-aika»1
Normaali <440 ms <430 ms <450 ms
Rajatapaus 440–460 ms 430–450 ms 450–470 ms
Pidentynyt (huippu 2–4 %) >460 ms >450 ms >470 ms

Kirjallisuutta

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Artikkelin tunnus: pgr00019 (200.006)
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