Life threatening dysrhythmias

BACKGROUND: Prevalence of microvolt T-wave alternans (TWA) and the strength of its association with torsade de pointes (TdP) history have not been fully investigated in patients with long QT syndrome (LQTS). METHODS AND RESULTS: Twenty-four-hour continuous 12-lead ECGs were recorded in 10 healthy subjects (5 men; median age, 21.5 years) and 32 patients (13 men; median age, 13 years) with LQTS types 1 (n=18), 2 (n=4), 3 (n=4), and unidentified (n=6). Peak TWA was determined by the Modified Moving Average method...

BACKGROUND: This study aimed to evaluate the use of QT intervals, their diagnostic predictive value in patients with syncope and their relationship with syncope severity. METHODS: One hundred and forty nine patients with a diagnosis of syncope were admitted to Internal Medicine departments at the University of Palermo, Italy, between 2006 and 2012, and 140 control subjects hospitalised for other causes were enrolled. QT maximum, QT minimum, QTpeak, QT corrected, QT dispersion and Tpeak-to-Tend interval were compared between two groups...

OBJECTIVE: In the light of the recent United States Food and Drug Administration (FDA) warning to clinicians on using previously approved doses of citalopram because of the purported higher risk of torsade de pointes (TdP), we pursued the broader question: are selective serotonin reuptake inhibitor (SSRI) antidepressant agents as a group unsafe because they might induce QTc interval prolongation and TdP? METHOD: We reviewed the literature and found only 15 case reports (6 of fluoxetine, 1 of sertraline and 8 of citalopram) of SSRI-associated QTc interval prolongation linking to TdP...

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PURPOSE: To evaluate the effect of sevoflurane or ketamine on the corrected QT (QTc) interval and the interval from the peak to the end of the T wave (Tp-e) during electroconvulsive therapy (ECT) in patients with major depression. METHODS: This prospective, randomized, double-blinded study included 24 patients that were randomly allocated to receive sevoflurane (group S) or ketamine (group K) for ECT session. Group S patients received 8 % sevoflurane for anesthesia induction, which was maintained at 2-4 % until delivery of the electrical stimulus...

No abstract text is available yet for this article.

C-reactive protein (CRP) and corrected QT (QTc) interval are predictors of cardiovascular disease. Whether CRP is associated with QTc interval and QT prolongation is unknown in hypertensive patients. We recruited hypertensive patients from a cardiovascular clinic in a tertiary medical center in Taiwan. All received standard 12-lead electrocardiogram examination. QT prolongation was defined as QTc interval ≥ 440 ms in men or ≥ 450 ms in women. High-sensitive CRP kits were used for the measurement of the CRP levels...

Hypothermia is a common environmental emergency encountered by physicians and is associated with a variety of electrocardiographic (ECG) abnormalities. The classic and well-known ECG manifestations of hypothermia include the presence of J (Osborn) waves, interval (PR, QRS, QT) prolongation, and atrial and ventricular arrhythmias. There are less well defined and known ECG signs of hypothermia, which in fact may simulate findings of acute coronary ischemia, Brugada syndrome, or even pericarditis. Although classical ECG changes seen in hypothermia certainly serve as an important clinical clue for prompt identification and management of this easily curable life-threatening entity, physicians should, however, be able to maintain a high suspicion for recognition and differentiation of less common ECG abnormalities encountered in hypothermia...

No abstract text is available yet for this article.

BACKGROUND: Both type 1 myotonic dystrophy (MD1) and Brugada syndrome (BrS) may be complicated by conduction disturbances and sudden death. Spontaneous BrS has been observed in MD1 patients, but the prevalence of drug-induced BrS in MD1 is unknown. OBJECTIVE: The purpose of this study was to prospectively assess the prevalence of type 1 ST elevation as elicited during pharmacologic challenge with Class 1C drugs in a subgroup of MD1 patients and to further establish correlations with ECG and electrophysiologic variables and prognosis...

We present a case of a high-risk 19-year-old female with long-QT syndrome (LQTS) with compound mutations. She had a history of aborted cardiac arrest and syncope and had received treatment with propranolol for 15 years. However, because she developed adult-onset asthma we tried to switch propranolol, a nonselective beta-blocker, to beta-1-cardioselective agents, bisoprolol and metoprolol. These resulted in both a markedly prolonged corrected QT interval and the development of LQTS-associated arrhythmias. Eventually, propranolol was reinitiated at a higher dose with the addition of verapamil, and she has had no further cardiac or asthmatic events for 5 years...