QTc Interval Prolonged: Causes & Reasons

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Possible Causes for QTc Interval Prolonged

Cardiodysrhythmic Potassium-Sensitive Periodic Paralysis

Her mother had normal serum electrolytes, but had prolonged QTc interval (0.46 seconds). [content.iospress.com]

Electrocardiogram demonstrated sporadic and isolated ventricular ectopy and prolonged QT interval (QTc=490 ms). [scielo.br]

These may include a prolonged QT interval. [hkpp.org]

Torsades De Pointes

RESULTS: QTc interval prolongation is an established, though imperfect, risk marker for TdP. [ncbi.nlm.nih.gov]

The QTc interval is always prolonged in TCM; however, TdP is rarely reported in patients with TCM. [ncbi.nlm.nih.gov]

Quetiapine was discontinued after 1 dose because of QTc interval prolongation. [ncbi.nlm.nih.gov]

Long QT Syndrome

In LQT2 male patients, this was preceded by a progressive QTc interval prolongation. [ncbi.nlm.nih.gov]

interval prolongation. [doi.org]

John McDonough and Philipp Lirk, QTc INTERVAL PROLONGATION, Gastroenterology Nursing, 10.1097/SGA.0000000000000077, 37, 6, (446-449), (2014). [oadoi.org]

Torsade-De-Pointes Syndrome with Short Coupling Interval

Pharmacists are often consulted about medications which are known to prolong the QTc interval. [pubfacts.com]

Prolonged QTc interval of 540 ms (greater than half the R-R interval). Ventricular ectopics with ‘R-on-T’ phenomenon; the second PVC initiates a run of TdP. NB. [lifeinthefastlane.com]

"Prolonged QTc interval and torsades de pointes induced by citalopram". Tex. Heart Inst. J. 39 (1): 68 – 70. PMC 3298934. [ipfs.io]

Long QT Syndrome 6

Many drugs can prolong the QTc interval. [radcliffecardiology.com]

Long QT Syndrome Genetic disorder (1:5,000-10,000) ECG evidence: QTc interval prolonged >440 ms in males >450 ms in females Hallmark arrhythmia: Torsade de pointes VT Primary [de.slideshare.net]

Most clinicians consider a corrected QT interval (QTc) of >440 msec for males and >450 msec for females to be prolonged. [uspharmacist.com]

Long QT Syndrome 15

(in some patients) recurrent episodes of ventricular fibrillation sudden death (in some patients) prolonged qtc interval on electrocardiogram (ecg) notched t waves on ecg [malacards.org]

qtc interval 31 HP:0005184 4 ventricular fibrillation 31 HP:0001663 Symptoms via clinical synopsis from OMIM: 56 Cardiovascular Heart: cardiac arrest (in some patients) bradycardia [malacards.org]

Long Qt Syndrome 15: 31 # Description HPO Frequency HPO Source Accession 1 cardiac arrest 31 occasional (7.5%) HP:0001695 2 bradycardia 31 occasional (7.5%) HP:0001662 3 prolonged [malacards.org]

Long QT Syndrome 10

The ECG shows not only the obvious QTc interval prolongation (QTc 631 ms by Bazett formula) but also prolongation of the Tp-e interval (Tp-e 126 ms) In the operating room, [jaclinicalreports.springeropen.com]

The degree of corrected QT interval (QTc) prolongation was an independent predictor of CEs. [acc.org]

When measuring the degree of QT interval prolongation, it is necessary to correct for the patient’s heart rate, termed QTc. [geneticheartdisease.org]

Long QT Syndrome 13

Many drugs can prolong the QTc interval. [radcliffecardiology.com]

Most clinicians consider a corrected QT interval (QTc) of >440 msec for males and >450 msec for females to be prolonged. [uspharmacist.com]

It can also be recommended that whenever the QTc interval is prolonged, that it be verified manually. [ecgwaves.com]

Long QT Syndrome 14

Name Long Qt Syndrome 14 Synonyms - Classification cardiac, genetic Phenotypes Autosomal dominant inheritance ; Cardiac arrest ; Prolonged QTc interval ; Sudden death ; Ventricular [mousephenotype.org]

Most clinicians consider a corrected QT interval (QTc) of >440 msec for males and >450 msec for females to be prolonged. [uspharmacist.com]

Hypokalemia, hypocalcemia, and use of loop diuretics are risk factors for QTc interval prolongation. [4] LQTS has been recognized as mainly Romano-Ward syndrome (ie, familial [emedicine.medscape.com]

Ventricular Arrhythmia

ECG at presentation revealed frequent ectopy and QT/QTc interval prolongation; at follow-up 9 months later the QT/QTc intervals were normalized. [ncbi.nlm.nih.gov]

interval prolongation. [doi.org]

RESULTS: Of the 124 Caucasian cases, 95 (77%) were QTc interval prolongation-related; mean age was 62 years (SD 15), and 63% were female. [ncbi.nlm.nih.gov]

Long QT Syndrome 8

Diabet Med 18 : 199 –205, 2001 ↵ Suys BE, Huybrechts SJ, De Wolf D, Op De Beeck L, Matthys D, Van Overmeire B, Du Caju MV, Rooman RP: QTc interval prolongation and QTc dispersion [care.diabetesjournals.org]

Many drugs can prolong the QTc interval. [radcliffecardiology.com]

Long QT Syndrome 12

QTc interval was significantly prolonged by ACh：0.519±0.029 sec^ to 0.688±0.067 sec^ in QT syndrome but not in the healthy control group. [dspace.lib.niigata-u.ac.jp]

Following a case report in which intracoronary acetylcholine (ACh) induced QT prolongation, the effect of Ach on the QT interval was studied. [dspace.lib.niigata-u.ac.jp]

Cisapride Poisoning

The ECG showed a prolonged QTc interval (0.490) calculated by the Bazett formula. [fn.bmj.com]

Examples include combinations of drugs that prolong the QTc interval resulting in ventricular arrhythmias, and combining drugs with hyperkalemic effects resulting in hyperkalemia [hanstenandhorn.com]

Non-cardiac QTc-prolonging drugs and the risk of sudden cardiac death. Eur Heart J 2005;26:2007-2012. Recanatini M, Poluzzi E, Masetti M, et al. [dpic.org]

Organophosphate Poisoning

Previous reports indicate that in contrast to normal heart rate-corrected QT intervals (QTc), QTc prolongation might be indicative of a poor prognosis for patients exposed [ncbi.nlm.nih.gov]

Pancreatitis is possible, and organophosphates may cause arrhythmias such as heart block and QTc interval prolongation. [msdmanuals.com]

By the end of the study, 18 of 118 (15.2%) patients had died, including 3 of 75 (4.0%) patients with normal QTc intervals and 15 of 43 (34.9%) patients with prolonged QTc [ncbi.nlm.nih.gov]

Short QT Syndrome Type 1

Measurement of the QT interval and the risk associated with QTc interval prolongation: a review. Am J Cardiol. 1993 Aug 26;72(6):23B-25B. [en.ecgpedia.org]

It can also be recommended that whenever the QTc interval is prolonged, that it be verified manually. [ecgwaves.com]

Diffuse Intraventricular Block

Note the sinus bradycardia, the prolonged QT interval (QTc is not prolonged) and the Osborn J wave, most prominently in leads V2-V5 An ECG of a patient with a body temperature [en.ecgpedia.org]

(and QTc-interval) Hypokalaemia * Hypomagnesaemia Hypocalcaemia Myocardial ischemia Elevated intracranial pressure Sodium-channel blockers Hypothermia Congenital prolonged [lifeinthefastlane.com]

QTc interval; low voltage; and signs indicating previous myocardial infarction. [journals.plos.org]

Phenothiazine Poisoning

Drugs That Prolong the QTc Interval There are no studies of the co-administration of thioridazine and other drugs that prolong the QTc interval. [rxlist.com]

QTc interval and pupillary meiosis is indicative of suspected phenothiazine overdose.[1] Severe extrapyramidal reactions are also commonly seen. [medscape.com]

However, thioridazine has been shown to prolong the QTc interval in a dose-dependent fashion. [rxlist.com]

Dridol - Teratogenic Agent

If combined, monitor for QTc interval prolongation and ventricular arrhythmias. Patients with additional risk factors for QTc prolongation may be at even higher risk. [drugs.com]

[…] of the QTc interval. [journals.lww.com]

Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. [drugs.com]

Jervell-Lange-Nielsen Syndrome Type 1

QTc interval in the absence of congenital deafness. [statpearls.com]

Andersen syndrome is a rare, clinically pleiotropic disorder characterized by mild prolongation of the QTc interval (but often marked prolongation of the QUc interval), ventricular [revespcardiol.org]

QTc interval. [wikidoc.org]

Jervell-Lange-Nielsen Syndrome Type 2

Post-anaesthetic ECG showed marked prolongation of the QTc interval (570-690 msec). [ncbi.nlm.nih.gov]

QTc interval in the absence of congenital deafness. [statpearls.com]

QTc intervals (0.46, 0.50, and 0.45 seconds, respectively). [ncbi.nlm.nih.gov]

Dofetilide

Safety assessment included monitoring for the occurrence of excessive QTc interval prolongation and torsade de pointes. [ncbi.nlm.nih.gov]

Dofetilide-induced corrected QT (QTc) interval prolongation is a surrogate for the degree of drug effect, but the relationships between drug-induced QTc interval prolongation [ncbi.nlm.nih.gov]

[…] in the QTc interval. [ncbi.nlm.nih.gov]

Jervell-Lange-Nielsen Syndrome

Introduction Jervell and Lange Nielsen syndrome (JLNS) is a rare autosomal recessive disorder characterized by bilateral sensorineural hearing loss and a prolonged QTc interval [statpearls.com]

The ECG of both the younger brother and father showed a prolonged QTc interval of >0.48 s, but they were asymptomatic. [annalsofian.org]

Electrocardiogram (ECG) showed prolonged QTc interval (533 mSec) [Figure 1]. Diagnosis of Jervell and Lange-Nielsen Syndrome was made. [ijaweb.org]

Thioridazine

QTc interval >450msec. [empr.com]

Concomitant drugs that prolong QTc interval, CYP2D6 inhibitors (eg, fluoxetine within past 5 weeks, paroxetine), or others that inhibit thioridazine metabolism (eg, duloxetine [empr.com]

QTc interval prolongation with CYP2D6 inhibitors (eg, fluoxetine, paroxetine) or inhibitors of thioridazine metabolism (eg, duloxetine, fluvoxamine, propranolol, pindolol) [empr.com]

Long QT Syndrome 9

The QTc interval and QTc-difference by changing the body position were calculated. All children with long-QT syndrome were treated with propranolol. [physiciansweekly.com]

QTc was prolonged among long-QT syndrome children while lying down and when standing up, compared to controls. [physiciansweekly.com]

Propionic Acidemia

Stein Prolonged QTc intervals and decreased left ventricular contractility in patients with propionic acidemia J Paediatr, 150 (2007), pp. 192-197 [6] R.S. [analesdepediatria.org]

Prolonged QTc intervals and decreased left ventricular contractility in patients with propionic acidemia. J Paediatr, 150 (2007), pp. 192-197 [6] R.S. [analesdepediatria.org]

QT interval (QTc > 440 ms), and that the interval was longer than 460 ms in 60%. [analesdepediatria.org]

Ondansetron

[…] recommends avoiding concurrent use with drugs known to prolong the QTc interval. [pdr.net]

Toremifene has been shown to prolong the QTc interval in a dose- and concentration-related manner. [pdr.net]

QTc interval prolongation can lead to Torsade de Pointes (TdP), a potentially life-threatening heart rhythm abnormality. [healthycanadians.gc.ca]

Hypocalcemia

We reported a case 61-year-old woman who received a single dose of denosumab and developed severe symptomatic hypocalcemia associated with prolong QTc interval requiring hospitalization [ncbi.nlm.nih.gov]

Investigation revealed a severe corrected hypocalcemia (0.97 mmol/l) with a prolonged QTc interval on ECG of 515 ms. [endocrine-abstracts.org]

The ECG hallmark of hypocalcemia remains the prolongation of the QTc interval because of lengthening of the ST segment, which is directly proportional to the degree of hypocalcemia [web.archive.org]

Short QT Syndrome

Initially, flecainide seemed to prolong slightly QTc interval and reduce the inducibility of ventricular fibrillation during electrophysiological study (5) but later studies [escardio.org]

At fast heart rates, the calculated QTc may appear normal (= ”pseudonormal” QTc) However, as the heart rate slows, the QTc typically fails to prolong. [litfl.com]

Serial ECGs or Holter monitoring at rest may be used to try and capture short QT intervals during periods of relative bradycardia (heart rate 60-80bpm). [litfl.com]

Bupropion Poisoning

QT interval corrected for heart rate (QTc). [mja.com.au]

Clinical features may include: Prolongation of QRS and QTc intervals. Hypotension requiring vasopressors. [emcrit.org]

PR interval: 256 ms, QRS duration: 144 ms, corrected QT (QTc): 495 ms. aVR, augmented vector right; aVL, augmented vector left; aVF, augmented vector foot. Fig. 3. [e-jnc.org]

Cardiac Arrhythmia

OBJECTIVE: Positive-controlled clinical studies have shown a dose dependent effect of buprenorphine transdermal system on QTc interval prolongation. [ncbi.nlm.nih.gov]

[…] of QTc intervals. [ncbi.nlm.nih.gov]

Women have longer average QTc intervals at baseline compared with men and are at increased risk of drug-induced QTc prolongation and arrhythmia. [doi.org]