Cases reported "Long QT Syndrome"

Filter by keywords:



Filtering documents. Please wait...

1/95. ventricular fibrillation related to reversal of the neuromuscular blockade in a patient with long qt syndrome.

    The long qt syndrome (LQTS) is associated with syncopal attacks or even sudden death at a young age due to ventricular fibrillation. We report a patient with an undiagnosed LQTS who had an episode of cardiac arrest during the final part of general anesthesia, immediately after the drugs for reversal of the neuromuscular blockade were given. We suggest that the administration of glycopyrronium might have been the provoking factor in this patient.
- - - - - - - - - -
ranking = 1
keywords = block
(Clic here for more details about this article)

2/95. Preoperative hypoglycaemia, propranolol and the Jervell and Lange-Nielsen syndrome.

    The Jervell and Lange-Nielsen syndrome is an autosomal recessive trait characterized by deafness and electrocardiographic changes. These changes include prolongation of the QT interval and T-wave inversion. Treatment may include the use of beta-blockers to prevent the development of malignant ventricular arrhythmias and sudden death. We report a patient with this syndrome, who was receiving propranolol orally and who became hypoglycaemic during the preoperative fasting period prior to cochlear implantation.
- - - - - - - - - -
ranking = 0.2
keywords = block
(Clic here for more details about this article)

3/95. A variant of long qt syndrome manifested as fetal tachycardia and associated with ventricular septal defect.

    Two patients with a novel variant of long qt syndrome are described. The clinical course was characterised by an in utero onset of ventricular tachycardia and atrioventricular block (at 26 and 30 weeks' gestational age, respectively), and an association with a ventricular septal defect. Studies of both patients' families identified relatives with prolonged QT interval, syncope, or sudden death. One patient died of intractable ventricular tachycardia at 4 days old. The other received beta blocker treatment and a pacemaker. She died suddenly at the age of 10 months. The unique association with ventricular septal defect and the malignant clinical course warrants further molecular diagnosis of this novel variant of long qt syndrome.
- - - - - - - - - -
ranking = 0.4
keywords = block
(Clic here for more details about this article)

4/95. Prominent bifid T waves observed in the QT prolongation caused by complete atrioventricular blockade in a hypokalemic diabetic patient.

    A 63-year-old diabetic man was admitted with general fatigue. Electrocardiogram (ECG) on admission showed complete atrioventricular (AV) blockade associated with prominent bifid T waves. The second component of the bifid T waves was distinguished from U waves by the beat-to-beat varying bifidity and the nadir between the two components located at > or = 1 mm above the isoelectric line. Range of absolute QT interval was 535 to 650 ms. hypokalemia (3.6 mEq/L) was noted at admission. Partial restoration of the potassium level (3.9 mEq/L) prior to temporary ventricular demand pacing obscured the bifid T waves and attenuated the QT prolongation and dispersion to some extent (absolute QT interval ranging 520 to 620 ms). It was concluded that marked bradycardia caused by complete AV blockade (ie, a junctional escaped rhythm at a rate of 42 beats/min), hypokalemia, and underlying diabetes mellitus contributed in concert to the QT prolongation and dispersion leading to the prominent bifid T waves.
- - - - - - - - - -
ranking = 1.2
keywords = block
(Clic here for more details about this article)

5/95. Homozygous premature truncation of the HERG protein : the human HERG knockout.

    Background-In long-QT syndrome (LQTS), heterozygosity for a mutation in 1 of the K( ) channel genes leads to prolongation of the cardiac action potential, because the aberrant protein exhibits "loss of function." HERG, which is involved in LQT2, is the gene encoding the rapid component of the delayed rectifier, I(Kr). methods and Results-In a consanguineous family, a stillbirth was followed by the premature birth of a child in distress due to ventricular arrhythmia in the presence of QT prolongation. LQTS was diagnosed, beta-blocker therapy was begun, and a pacemaker was implanted. She developed well and remained symptom-free for 1.5 years. In the index patient, we identified a duplication of bp 558 to 600 in exon 4 of HERG on both alleles. This will result in a frameshift and a premature stop codon before the S1 domain of the HERG protein. Because it is present on both alleles, no functional I(Kr) is anticipated. The same mutation was found heterozygously in both parents and homozygously in the stillborn brother. Conclusions-It is concluded that absence of I(Kr) gives rise to a severe cardiac phenotype, with no indication of malfunction of any other organ.
- - - - - - - - - -
ranking = 0.2
keywords = block
(Clic here for more details about this article)

6/95. Congenital long-QT syndrome: a case report illustrating diagnostic pitfalls.

    This article reviews the clinical course of a 10-year-old child with a lifelong history of seizures and congenital deafness who presented after an episode of sudden cardiac arrest secondary to long-QT syndrome-induced torsade de pointes. Jervell-Lange-Nielsen syndrome is a rare cardioauditory syndrome in which affected subjects are susceptible to recurrent syncope and sudden death from ventricular dysrhythmias, usually before the second decade of life. Careful evaluation of suspected subjects is important because of the variability of the QTc interval. Recent research has identified specific gene sequences that encode ion channels responsible for both prolonged QTc interval and deafness. Treatment of symptomatic cardiac disease with beta-blockers in combination with pacemakers and automated internal cardioverter defibrillators can markedly improve quality of life and suppress ventricular dysrhythmias even in the most severely affected subjects. The recent identification of gene sequences identifying some congenital long-QT syndromes may improve screening methods for affected patients and lead to potential therapeutic intervention.
- - - - - - - - - -
ranking = 0.2
keywords = block
(Clic here for more details about this article)

7/95. Fetal presentation of congenital long qt syndrome.

    Thirty-two-week prenatal ultrasound revealed a fetal heart rate of 100 bpm with decreased variability on the heart rate tracing. Echocardiogram documented normal anatomy and sinus bradycardia. Newborn electrocardiogram revealed sinus rhythm at 100 bpm with a QTc of 0.657. Follow-up electrocardiogram revealed a QTc interval of 0.568, 2:1 atrioventricular block with a ventricular rate of 60 bpm, and ventricular ectopy. The infant received a pacemaker and beta-blocker therapy. long qt syndrome should be in the differential diagnosis of the fetus with bradycardia and decreased heart rate variability in the absence of distress. early diagnosis allowed for preventative care in the infant and identification of family members at risk.
- - - - - - - - - -
ranking = 0.4
keywords = block
(Clic here for more details about this article)

8/95. swimming, a gene-specific arrhythmogenic trigger for inherited long qt syndrome.

    OBJECTIVE: To determine the genetic basis for long qt syndrome (LQTS) in a cohort of patients with a personal history or an extended family history of a swimming-triggered cardiac event. patients AND methods: After review of the Mayo Clinic unit medical record system, blood samples or archived autopsy tissue samples were obtained from a retrospective cohort of 35 cases diagnosed as having autosomal dominant LQTS. Exon-specific amplification by polymerase chain reaction and direct sequence analyses were performed on the entire KVLQT1 gene. RESULTS: Six cases had a personal history or an extended family history of a near drowning or drowning. In all 6 cases, LQTS-causing mutations in KVLQT1 gene were identified: 3 deletion mutations, 2 donor splice site mutations, and 1 missense mutation. One of the mutations, a novel donor splicing defect, was determined by postmortem molecular analysis of a paraffin-embedded tissue block from a 12-year-old girl who died in 1976. Distinct KVLQT1 mutations were demonstrated in 3 of the remaining 29 cases. The overall frequency of KVLQT1 defects in LQTS was 100% (6/6) in those with and 10% (3/29) in those without a personal history or an extended family history of drowning or near drowning (P<.001). CONCLUSION: swimming appears to be a gene-specific (KVLQT1) arrhythmogenic trigger for LQTS. This study provides proof of principle that an unexplained drowning or near drowning may have a genetic basis.
- - - - - - - - - -
ranking = 0.2
keywords = block
(Clic here for more details about this article)

9/95. long qt syndrome with a high mortality rate caused by a novel G572R missense mutation in KCNH2.

    In a four-generation family with long qt syndrome, syncopes and torsades de pointes ventricular tachycardia (TdP) were elicited by abrupt awakening in the early morning hours. The syndrome was associated with a novel KCNH2 missense mutation, G572R, causing the substitution of a glycine residue at position 572, at the end of the S5 transmembrane segment of the HERG K( )-channel, with an arginine residue. This segment is involved in the channel pore and the mutation may cause a reduction in the rapidly activating delayed rectifier K current (Ikr), or changed gating properties of the ion channel, leading to prolonged cardiac repolarization. The electrocardiograms of affected persons showed prolonged QT interval and notched T waves. Despite treatment with atenolol, 200 mg twice daily, the proband still experienced TdP episodes. Three untreated relatives of the proband died suddenly, and unexpectedly, at 18, 32, and 57 years of age. The G572R mutation is thus associated with a high mortality rate, and the clinical presentation illustrates that some mutations may not be controllable by just beta-blockade.
- - - - - - - - - -
ranking = 0.2
keywords = block
(Clic here for more details about this article)

10/95. Laser surgery in a patient with Romano-Ward (long QT) syndrome and an automatic implantable cardioverter defibrillator.

    A 48-year-old woman with romano-ward syndrome (a hereditary long qt syndrome), asthma and an automatic implantable cardioverter defibrillator presented for laser surgery for debulking of a massive nasopharyngeal tumour prior to radiotherapy. Automatic implantable cardioverter defibrillators have only relatively recently been used to treat patients with the long qt syndrome and are indicated for the high-risk individual when conventional treatment has failed or when beta-blockers are contraindicated. If surgery requires the use of surgical diathermy, a cardiac technician must be present to deactivate the defibrillator and external pacing electrodes are sited on the chest until the defibrillator can be reactivated. radiotherapy requires both deactivation and shielding of the device.
- - - - - - - - - -
ranking = 0.2
keywords = block
(Clic here for more details about this article)
| Next ->


Leave a message about 'Long QT Syndrome'


We do not evaluate or guarantee the accuracy of any content in this site. Click here for the full disclaimer.