Repolarization characteristics and incidence of Torsades de Pointes in patients with acquired complete atrioventricular block

Yasemin Turan Bozkaya, Zuhal Eroğlu, Meral Kayikçioğlu, Serdar Payzin, Levent H Can, Hakan Kültürsay, Can Hasdemir
Anatolian Journal of Cardiology: AKD 2007, 7 Suppl 1: 98-100

OBJECTIVE: Torsades de pointes (TdP) during bradyarrhythmias have been reported to be associated with gender, degree of QT prolongation and duration of bradyarrhythmia. We sought to investigate the repolarization characteristics on 12-lead electrocardiogram (ECG) and the incidence of TdP in patients with acquired complete atrioventricular block (CAVB).

METHODS: Fifty consecutive patients with acquired CAVB were included in the study. Patients with coronary artery disease, systolic dysfunction and previous cardiac surgery were excluded. Patients were monitored during hospitalization for ventricular arrhythmias (VA). Serum potassium, magnesium, calcium levels and thyroid-stimulating hormone were measured. Heart rate, QRS duration, QT/QTc, JT/JTc and Tpeak-Tend intervals were measured. Pathologic U waves, T-U complex, and QT morphologies were remarked.

RESULTS: Patients presented with presyncope (n=39, 78%), syncope (n=12, 24%), and palpitations (n=8, 16%). All patients were in sinus rhythm. Duration of CAVB was 8.5 days (median). Patients were divided into two groups based on JT interval. Group 1 (JT=or>500 ms, n=13) tended to have more female patients and more VAs in comparison to Group 2 (JT<500 ms, n=37). Group 1 patients had more pathologic U waves and T-U complexes, longer Tpeak-Tend intervals, and more long QT2 syndrome (LQT2)-like QT morphology in comparison to Group 2 patients. Group 2 patients had more often syncope. One patient in Group 2 developed ventricular fibrillation in the presence of hypokalemia and hypomagnesemia.

CONCLUSION: Torsades de Pointes during CAVB was rare among our patient population. The predictors of VA during CAVB were presence of prolonged QTc/JTc intervals, pathologic U wave and T-U complex, prolonged Tpeak-Tend interval, and LQT2-like QT morphology.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"