QT Variables of Isolated Mitral Valve Prolapse

Abstract

Purpose: It is thought that arrhythmias are responsible for sudden deaths in patients with mitral valve prolapse (MVP). QT intervals may predict malignant arrhythmia potential in these patients. The aim of the present study is to assess QT variables in patients with MVP. Methods : We studied 46 patients with non-rheumatic, uncomplicated and isolated MVP and 25 healthy control subjects. All individuals underwent full M-mode; two -dimensional and color-Doppler examinations. MVP was defined as superior displacement of the mitral leaflets of more than 2 mm during systole and as a maximal leaflet thickness of at least 5 mm during diastole. Maximum (QTmax), minimum (QTmin) durations, corrected QT intervals and QT dispersion were measured in every case. The results of MVP patients were compared with the data gathered from the control cases. Results: Demographic and clinical variables were similar between the two groups. Anterior mitral leaflet thickness (AMLD), maximal leaflet displacement (DMR) and degree of mitral regurgitation (DMR) were found to be significantly higher in the patient group. QTc max, QT dispersion (QTd) and corrected QT dispersion (QTcD) were also significantly higher in MVP patients. A significant and fairly strong correlation was found between QTc max, QTcD and AMLT, MLD and DMR. Conclusion: QT durations were significantly increased in patients with isolated MVP, which may explain increased incidence of ventricular arrhythmias and sudden death in this population. Furthermore QT variables were related with the mitral leaflet thickness and degree of mitral regurgitation; which means QT variables increases with the the severity of the disease

Keywords

• mitral valve prolapse,QT dispersion,echocardiography

İzole Mitral Kapak Prolapsusunda QT Degiskenleri

Abstract

Amaç: Mitral Kapak prolapsusu (MKP) ile iliskili ani ölümlerden aritmilerin sorumlu oldugu düsünülmektedir. QT araligi ölçümü bu hastalardaki malign aritmi potansiyelini tahmin edebilir. Bu çalismanin amaci MKP hastalarinda QT degiskenlerini arastirmaktir. Gereç ve Yöntem: Romatizmal ve komplike olmayan izole MKP’lu 46 hasta ve 25 saglikli birey kontrol grubu olarak çalisildi. Çalismaya alinan tüm bireylere, M-mod, 2-boyutlu ve renkli Doppler ekokardiyografi uygulandi. MKP tanimi; sistol sirasinda mitral yaprakçiklarin en az 2 mm atriuma dogru bombelesmesi ve diastolde yaprakçik kalinliginin 5 mm üzerinde saptanmasi ile kondu. Ayrica her hastada maksimum (QTmax), minimum (QTmin), düzeltilmis QT (QTc) ve QT dispersiyonu hesaplandi. MKP hastalarinin sonuçlari kontrol grubu ile karsilastirildi. Bulgular: Hastalarin demografik ve klinik verileri kontrol grubu ile benzerdi. Hastalarin anterior mitral yaprakçik kalinligi (AMYK), maksimum yaprakçik kaymasi (MYK) ve mitral yetersizlik orani (MYO) kontrol grubundan anlamli derecede yüksekti. Yine, QTc max, QTd ve düzeltilmis QTcD hasta grubunda anlamli derecede yüksek bulundu. QTc max ve QTcD ile ekokardiyografik parametrelerden AMYK, MYK ve MYO arasinda anlamli ve oldukça güçlü korelasyon saptandi. Sonuç: Izole MVP’li hastalarda QT araligi anlamli derecede uzamaktadir. Bu durum hasta grubunda yasanan artmis ventriküler aritmi ve ani ölüm sikligini açiklayabilir. Dahasi, QT degiskenleri mitral yaprakçigin kalinligi ve mitral yetersizlik derecesi ile, dolayisi ile MKP’nun agirligi ile iliskilidir

Keywords

• mitral kapak prolapsusu,QT dispersiyonu,ekokardiyografi

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