The relationship between myocardial bridges and myocardial repolarization

Öz

Background: Although the muscular bridge (MB) which seen in the coronary arteries is known to be a benign condition, it is reported to be associated with adverse cardiac events in some studies. Although some condition such as coronary ischemia have been blamed in the occurrence of these adverse events, it is thought that the negative effects of myocardial electrical conduction will contribute to this situation.In this study, the relationship between electrocardiography parameters that demonstrate the electrical activity of the heart and the muscular bridgewas investigated.

Material and Methods: This study included 36 patients (26 males, mean age 56 years) who were diagnosed with MB and 36 patients with normal coronary artery (30 male, mean age 51 years). 12- lead electrocardiography (ECG) was performed in supine position and QT interval, QT corrected (QTc), Tp-Te interval, Tp-Te/QT and Tp-Te/QTc measurements were performed. These parameters were compared between groups.

Results: There were no significant differences between MB group and control group in terms of clinical and baseline demographic characteristics However, QT interval, QTc, Tp-Te interval, Tp-Te / QT and Tp-Te / QTc were significantly higher in the MB group. (360 ± 1.9 vs 355±2.3, p <0.001; 428.1 ± 1.6 vs 417.3±1.4, p <0.001; 83.3 ± 1.4 vs 72.1±1.3, p <0.001; 0.24 ± 0.005 vs 0.2±0.004, p <0.001; 0.2±0.003 vs 0.17±0.003, p <0.001). Multivariate analysis was performed to determine the independent predictors of the Tp-e interval. The length of MB was detected as an independent predictor of Tp-Te interval. (β = 0.530, p = 0.005)

Conclusion: Length of MB is an independent predictor of Tp-Te interval.

Anahtar Kelimeler

• Myocardial bridge,Tp-Te interval,Bridge length

Miyokardiyal köprülenme ve miyokardiyal repolarizasyon ilişkisi

Öz

Amaç: Koroner arterlerde görülen Müsküler köprü (MK) iyi huylu bir durum olarak bilinmesine rağmen, bazı çalışmalarda olumsuz kardiyak olaylar ile ilişkisinin olduğu belirtilmektedir. Bu olumsuz olayların meydana gelmesinde koroner iskemi gibi bazı durumlar suçlansa da, miyokardiyal elektriksel iletimdeki olumsuzlukların da buna katkıda bulunacağı düşünülmektedir. Bu çalışma da kalbin elektriksel aktivitesini gösteren elektrokardiyografi parametreleri ile müsküler köprü arasındaki ilişki incelenmiştir.

Materyal ve Metod: Bu çalışmaya MK olan 36 hasta (26 erkek, yaş ortalaması 56 yıl) ve normal koroner arteri olan MK olmayan 36 kişi (30 erkek, yaş ortalaması 51yıl) kontrol grubu olarak kalınmıştır. İstirahat halinde yatar pozisyonda 12 kanallı elektrokardiyografi (EKG) çekilerek QT intervali, QT corrected (QTc), Tp-Te intervali, Tp-Te/QT ve Tp-Te/QTc ölçümleri yapılmıştır. Bu parametreler, gruplar arasında karşılaştırıldı.

Bulgular: MK ve kontrol grubu arasında klinik ve bazal demografik özellikler açısından anlamlı farklılık saptanmadı. Ancak, MK grubunda QT intervali, QTc, Tp-Te intervali, Tp-Te/QT ve Tp-Te/QTc anlamlı olarak yüksekti. (Sırasıyla 360±1.9’e karşın 355±2.3, p<0,001; 428.1±1,6‘e karşın. 417.3±1.4, p<0,001; 83.3±1.4‘e karşın 72.1±1.3, p<0,001; 0,24±0,005’e karşın0.2±0.004, p<0,001; 0,2±0,003’e karşın 0.17±0.003 p<0,001). Tp-e intervalinin bağımsız prediktörlerini belirlemek amacıyla multivariate analiz yapıldı. MB uzunluğu Tp-Te intervalinin bağımsız öngördürücüsü olarak saptandı. (β=0.530, p = 0.005)

Sonuç: MK uzunluğu, Tp-Te intervalinin bağımsız bir ön gördürücüsüdür.

Anahtar Kelimeler

• Myokardiyal köprülenme,Tp-Te interval,Miyokardiyal köprü uzunluğu

Kaynakça

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