BACKGROUND Heart rate-corrected QT interval (QTc) is the traditional method of assessing the duration of repolarization. Prolonged heart rate-corrected QT interval is associated with higher risk of mortality in patients with coronary heart disease (CHD) and in the general population. However, the QTc is typically not evaluated when QRS duration is > or =120 ms, because increased QRS duration (Q...

The QT interval of the electrocardiogram is prolonged in right and left bundle-branch block. Since the QT interval is not prolonged outside the normal range due to myocardial disease alone, this lengthening of the QT interval is due to the conduction defect and is probably due to delayed depolarization (and thus repolarization) of the heart. There is, however, a significant difference in the QT...

PURPOSE Opioids may affect changes in the corrected QT interval (QTc) during anesthetic induction. This study examine whether a single bolus of remifentanil would prolong QTc after laryngeal mask airway (LMA) insertion during sevoflurane induction. MATERIALS AND METHODS Forty women of American Society of Anesthesiologists physical status 1 (ASA PS1) undergoing gynecological surgery were studi...

convulsion is one of the most common problems in children and hypocalcemia is one the most frequent etiological items in children’s convulsion. corrected qt (qtc) in ekg is prolonged in hypocalcemia, so it can be a useful tool for evaluation of serum ionized calcium. in three groups (first seizure, multiple seizures, without seizure or control ) every 25 cases, qtc, serum ionized ca, total ca, ...

methadone is a synthetic opioid used as the standard treatment for narcotics dependence.cyp3a is the major enzyme to metabolize methadone. long qt syndrome and secondary tdp (a polymorphic ventricular tachycardia) to methadone is generally rare, but in the past few years, gained attention of many scientists as a potentially fatal complications caused by methadone. interact  with voltage-depende...

OBJECTIVE Sympathetic activity increases in patients with mitral stenosis (MS). The association between prolonged Tpeak-Tend (Tp-e) interval and increased sympathetic activity has been demonstrated. This study aimed to evaluate Tp-e interval, Tp-e/QT ratio, and Tp-e/corrected QT interval (QTc) ratio in patients with MS before and after balloon valvuloplasty. METHODS Thirty patients with sever...

BACKGROUND Methadone (ME) is commonly used in pain and palliative care (PPC) patients with refractory pain or intolerable opioid adverse effects (AEs). A unique ME AE is its corrected QT (QTc) interval prolongation risk, but most evidence exists in methadone maintenance therapy patients. OBJECTIVE Our goal was to identify QTc interval prolongation risk factors in PPC patients receiving ME and...

BACKGROUND Ramosetron is a relatively new 5-hydroxytryptamine three receptor antagonist with higher binding affinity and more prolonged duration of action compared to ondansetron. The present study was performed to evaluate the effects of ramosetron on QTc interval and possible cardiovascular adverse effects in patients undergoing cardiac surgery. METHOD A total of 114 patients who underwent ...

In hypertensive patients single doses of ketanserin 40 mg prolonged the corrected QT interval (QTc) for at least 8 hours, with a maximal increase of 35 ms (P less than 0.001, n = 6) after 2 hours. During chronic dosing (20 and 40 mg b.d.) the QTc was further prolonged, by 46 and 45 ms respectively. QTc prolongation after treatment with a mean dose of 73 mg/day for 7 weeks (n = 26) was significa...

Objectives: To test the hypothesis that the QTc of any lead of the ECG predicts death after stroke, and to determine which lead of the ECG carries the greatest risk of cardiac death when its QTc is measured. Design: Standard 12 lead ECGs were analysed by one observer who was blind to patient outcome. Setting: A major teaching hospital in Scotland. Patients: 404 stroke survivors were studied at ...