The Effect of Hypertensive Left Ventricular Hypertrophy on Ventricular Repolarization

Öz

Objective: The peak and end interval of the T wave (Tp-e), the Tp-e/QT ratio and the Tp-e/QTc ratio are new indices of ventricular repolarization and have been associated with ventricular arrhythmias. It is known that the presence of both hypertension and left ventricular hypertrophy is a risk factor for the development of ventricular arrhythmia and sudden cardiac death. In this study, we aimed to determine the effect of the presence of left ventricular hypertrophy on Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio in patients with hypertension.

Material and Methods: Three hundred and forty-six newly diagnosed hypertension patients were included in the study. Hypertension patients were divided into two groups according to the presence of echocardiographic left ventricular hypertrophy. Then, 175 age and gender adjusted patients were determined as a control group. Tp-e interval, Tp-e/QT and Tp-e/QTc ratios, QT and QTc values of all patients were measured by 12-lead electrocardiography and compared between the groups.

Results: There was no statistically significant difference in baseline characteristics among three groups. Tp-e interval, Tp-e/QT and Tp-e/QTc ratio were found to be longer in the hypertension group with left ventricular hypertrophy compared to both the control group and the group without left ventricular hypertrophy. Similarly, we observed that the QT and QTc values which are known as conventional parameters of ventricular repolarization were longer in the left ventricular hypertrophy group compared to the other two groups.

Conclusion: Our study revealed that the presence of left ventricular hypertrophy in hypertension patients increased the Tp-e interval, Tp-e/QT and Tp-e/QTc ratios. Our results show that the presence of left ventricular hypertrophy in patients with hypertension is one of the main risk factors for the development of arrhythmia.

Anahtar Kelimeler

• Hypertension
• Left ventricular hypertrophy
• Ventricular Repolarization.

HİPERTANSİF SOL VENTRİKÜL HİPERTROFİSİNİN VENTRİKÜLER REPOLARİZASYON ÜZERİNE ETKİSİ

Öz

Amaç: T dalgasının tepe ve sonu aralığı (Tp-e), Tp-e/QT oranı ve Tp-e/QTc oranı ventriküler repolarizasyonun yeni indeksleridir ve ventriküler aritmiler ile ilişkilendirilmiştir. Hem hipertansiyon hem de sol ventriküler hipertrofi varlığının ventriküler aritmi gelişimi ve ani kardiyak ölüm için bir risk faktörü olduğu bilinmektedir. Bu çalışmada, hipertansiyon hastalarında sol ventriküler hipertrofi varlığının Tp-e aralığı, Tp-e/QT oranı ve Tp-e/QTc oranı üzerindeki etkisini belirlemeyi hedefledik.

Gereç ve Yöntemler: Yeni tanı alan 346 hipertansiyon hastası çalışmaya dahil edildi. Hipertansiyon hastaları ekokardiyografik sol ventriküler hipertrofi varlığına göre iki gruba ayırıldı. Daha sonra yaş ve cinsiyet eşitlemesi yapılan 175 kontrol hastası belirlendi. Tüm hastaların Tp-e aralığı, Tp-e/QT ve Tp-e/QTc oranları, QT ve QTc değerleri 12 derivasyonlu elektrokardiyografi ile ölçülerek gruplar arasında karşılaştırıldı.

Bulgular: Her üç grup arasında bazal özellikler açısından istatistiksel olarak anlamlı bir fark bulunmadı. Tp-e aralığı, Tp-e/QT ve Tp-e/QTc oranının sol ventriküler hipertrofi gelişen hipertansiyon grubunda hem kontrol gurubuna göre hem de sol ventriküler hipertrofi olmayan hipertansiyon grubuna göre daha uzun olduğu tespit edildi. Benzer şekilde geleneksel parametreler olan QT ve QTc değerlerinin de sol ventriküler hipertrofi olan grupta diğer iki gruba göre uzun olduğunu tespit ettik.

Sonuç: Çalışmamız hipertansiyon hastalarında sol ventriküler hipertrofi varlığının Tp-e aralığı, Tp-e/QT ve Tp-e/QTc oranlarını arttırdığını ortaya çıkarmıştır. Sonuçlarımız hipertansiyon hastalarında aritmi gelişimi için ana risk faktörlerinden birisinin sol ventriküler hipertrofi varlığı olduğunu göstermektedir.

Anahtar Kelimeler

• Hipertansiyon
• Sol ventrikül hipertrofisi
• Ventriküler repolarizasyon

Kaynakça

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