Humans ; Diagnosis, Differential ; Long QT Syndrome/genetics* ; Syncope/diagnosis* ; Epilepsy/diagnosis* ; Electrocardiography

Early recognition and treatment for early warning electrocardiogram (ECG) of sudden death are very important to prevent and treat malignant arrhythmia and sudden death. Previous studies have found that R-on-T and T wave alternation, and QT interval prolongation are closely related to malignant arrhythmia or sudden death, which are included in the critical value of ECG.By analyzing the ECG characteristics of 4 patients with sudden death, we found that although the causes of the patients were different, there were transient prolongation of QT interval after premature contraction in 12 lead ECG, followed by malignant arrhythmia or sudden death. Thus, we thought that the transient prolongation of QT interval after premature contraction had a high value for warning malignant arrhythmia or sudden death. This phenomenon should be paid enough attention to reduce the risk of sudden death.
Arrhythmias, Cardiac/diagnosis* ; Death, Sudden ; Death, Sudden, Cardiac ; Electrocardiography ; Humans ; Long QT Syndrome/diagnosis*

Biological sex (being female or male) significantly influences the course of disease. This simple fact must be considered in all cardiovascular diagnosis and therapy. However, major gaps in knowledge about and awareness of cardiovascular disease in women still impede the implementation of sex-specific strategies. Among the gaps are a lack of understanding of the pathophysiology of women-biased coronary artery disease syndromes (spasms, dissections, Takotsubo syndrome), sex differences in cardiomyopathies and heart failure, a higher prevalence of cardiomyopathies with sarcomeric mutations in men, a higher prevalence of heart failure with preserved ejection fraction in women, and sex-specific disease mechanisms, as well as sex differences in sudden cardiac arrest and long QT syndrome. Basic research strategies must do more to include female-specific aspects of disease such as the genetic imbalance of 2 versus one X chromosome and the effects of sex hormones. Drug therapy in women also needs more attention. Furthermore, pregnancy-associated cardiovascular disease must be considered a potential risk factor in women, including pregnancy-related coronary artery dissection, preeclampsia, and peripartum cardiomyopathy. Finally, the sociocultural dimension of gender should be included in research efforts. The organization of gender medicine must be established as a cross-sectional discipline but also as a centered structure with its own research resources, methods, and questions.
Cardiomyopathies ; Cardiovascular Diseases ; Coronary Artery Disease ; Coronary Vessels ; Death, Sudden, Cardiac ; Diagnosis ; Drug Therapy ; Female ; Gonadal Steroid Hormones ; Heart Failure ; Humans ; Long QT Syndrome ; Male ; Peripartum Period ; Pre-Eclampsia ; Prevalence ; Risk Factors ; Sex Characteristics ; X Chromosome

Long QT syndrome (LQTs) is a rare congenital disorder of the heart's electrical activity. Patients with LQTs are at increased risk of developing fatal ventricular arrhythmias. Elevated levels of sympathetic stimulation can exacerbate this risk. Successful behavior management is indispensable in the treatment of patients with LQTs. However, many drugs involved in pharmacologic behavior management are known to adversely affect the QT interval. Therefore, careful selection of a sedative drug is essential in avoiding such incidences. A 10-year-old boy with a known diagnosis of LQTs required restorative treatment due to dental caries at the permanent molar. He required sedation since treatment was painful and dental phobia can trigger sympathetic stimulation, creating a dangerous situation for patients with LQTs. Therefore, the treatment was performed over two sessions under moderate sedation involving propofol combined with nitrous oxide. Restorative treatment was successful without any complications under sedation with a target-controlled infusion (TCI) of propofol. There was no significant QT prolongation during pulpal treatment. Propofol TCI may be a good candidate for sedation in patients with LQTs.
Arrhythmias, Cardiac ; Child ; Congenital, Hereditary, and Neonatal Diseases and Abnormalities ; Conscious Sedation* ; Dental Anxiety ; Dental Caries ; Diagnosis ; Humans ; Incidence ; Long QT Syndrome* ; Male ; Molar ; Nitrous Oxide ; Propofol*

Long QT syndrome (LQTs) is a rare congenital disorder of the heart's electrical activity. Patients with LQTs are at increased risk of developing fatal ventricular arrhythmias. Elevated levels of sympathetic stimulation can exacerbate this risk. Successful behavior management is indispensable in the treatment of patients with LQTs. However, many drugs involved in pharmacologic behavior management are known to adversely affect the QT interval. Therefore, careful selection of a sedative drug is essential in avoiding such incidences. A 10-year-old boy with a known diagnosis of LQTs required restorative treatment due to dental caries at the permanent molar. He required sedation since treatment was painful and dental phobia can trigger sympathetic stimulation, creating a dangerous situation for patients with LQTs. Therefore, the treatment was performed over two sessions under moderate sedation involving propofol combined with nitrous oxide. Restorative treatment was successful without any complications under sedation with a target-controlled infusion (TCI) of propofol. There was no significant QT prolongation during pulpal treatment. Propofol TCI may be a good candidate for sedation in patients with LQTs.
Arrhythmias, Cardiac ; Child ; Congenital, Hereditary, and Neonatal Diseases and Abnormalities ; Conscious Sedation* ; Dental Anxiety ; Dental Caries ; Diagnosis ; Humans ; Incidence ; Long QT Syndrome* ; Male ; Molar ; Nitrous Oxide ; Propofol*

BACKGROUND AND OBJECTIVES: Excessive catecholamine causes the alteration of cardiac structure and function. This study evaluated if there is any difference in left ventricular hypertrophy (LVH) and QTc prolongation in conditions with pheochromocytoma and Takotsubo cardiomyopathy (TC). SUBJECTS AND METHODS: We reviewed the medical records of 20 pheochromocytoma patients for cardiovascular events prior to diagnosis. The patient's clinical history and electrocardiographic and echocardiographic findings were compared to those of 20 patients diagnosed with TC. RESULTS: Left ventricular (LV) mass index (133.3+/-37.8 vs. 113.3+/-17.3, p=0.031), relative wall thickness (0.55+/-0.15 vs. 0.47+/-0.07, p=032) and elevated blood pressure (BP) were more prominent in pheochromocytoma compared to TC. The mean creatinine kinase-MB elevation, reduced LV systolic function and ST segment changes were more prominent in the TC group compared to the pheochromocytoma groups (all p<0.05). The prevalence of QTc prolongation was high in patients with pheochromocytoma (45%) and TC (55%), and TC male patients appeared to have a more prolonged QTc interval. Urine epinephrine (r=0.844, p=0.004) and norepinephrine level (r=0.782, p=0.013) were significantly correlated with LV mass index, and the predictors for the QTc prolongation were male gender and the presence of LVH. CONCLUSION: A prolonged QTc was prominent in pheochromocytoma and TC regardless of BP and systolic LV function, and LVH was more prominent in pheochromocytoma than TC.
Blood Pressure ; Catecholamines ; Diagnosis ; Echocardiography ; Electrocardiography ; Epinephrine ; Humans ; Hypertrophy, Left Ventricular* ; Long QT Syndrome ; Male ; Medical Records ; Norepinephrine ; Pheochromocytoma* ; Prevalence ; Takotsubo Cardiomyopathy*

Long QT interval is an important finding that is often missed by electrocardiogram interpreters. Long QT syndrome (inherited and acquired) is a potentially lethal cardiac channelopathy that is frequently mistaken for epilepsy. We present a case of long QT syndrome with multiple cardiac arrests presenting as syncope and seizures. The long QTc interval was aggravated by hypomagnesaemia and drugs, including clarithromycin and levofloxacin. Multiple drugs can cause prolongation of the QT interval, and all physicians should bear this in mind when prescribing these drugs.
Adult ; Defibrillators, Implantable ; Electrocardiography ; Heart Rate ; Humans ; Long QT Syndrome ; complications ; congenital ; diagnosis ; therapy ; Male ; Risk Factors ; Seizures ; complications

Timothy syndrome, long QT syndrome type 8, is highly malignant with ventricular tachyarrhythmia. A 30-month-old boy had sudden cardiac arrest during anesthesia induction before plastic surgery for bilateral cutaneous syndactyly. After successful resuscitation, prolonged QT interval (QTc, 0.58-0.60 sec) and T-wave alternans were found in his electrocardiogram. Starting beta-blocker to prevent further tachycardia and collapse event, then there were no more arrhythmic events. The genes KCNQ1, KCNH2, KCNE1 and 2, and SCN5A were negative for long QT syndrome. The mutation p.Gly406Arg was confirmed in CACNA1C, which maintains L-type calcium channel depolarization in the heart and other systems.
Anesthesia/*adverse effects ; Calcium Channels, L-Type/*genetics ; Death, Sudden, Cardiac/*etiology ; Electroencephalography ; Humans ; Infant ; Long QT Syndrome/*genetics ; Magnetic Resonance Imaging ; Male ; Methyl Ethers/adverse effects ; Nitric Oxide/adverse effects ; Polymorphism, Single Nucleotide ; Sequence Analysis, DNA ; Surgery, Plastic ; Syndactyly/diagnosis/*genetics/surgery

The long QT syndrome (LQTS) is a rare hereditary disorder in which affected individuals have a possibility of ventricular tachyarrhythmia and sudden cardiac death. We investigated 62 LQTS (QTc > or = 0.47 sec) and 19 family members whose genetic study revealed mutation of LQT gene. In the proband group, the modes of presentation were ECG abnormality (38.7%), aborted cardiac arrest (24.2%), and syncope or seizure (19.4%). Median age of initial symptom development was 10.5 yr. Genetic studies were performed in 61; and mutations were found in 40 cases (KCNQ1 in 19, KCNH2 in 10, SCN5A in 7, KCNJ2 in 3, and CACNA1C in 1). In the family group, the penetrance of LQT gene mutation was 57.9%. QTc was longer as patients had the history of syncope (P = 0.001), ventricular tachycardia (P = 0.017) and aborted arrest (P = 0.010). QTc longer than 0.508 sec could be a cut-off value for major cardiac events (sensitivity 0.806, specificity 0.600). Beta-blocker was frequently applied for treatment and had significant effects on reducing QTc (P = 0.007). Implantable cardioverter defibrillators were applied in 6 patients. Congenital LQTS is a potentially lethal disease. It shows various genetic mutations with low penetrance in Korean patients.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Asian Continental Ancestry Group/genetics ; Calcium Channels/genetics ; Child ; Child, Preschool ; Electrocardiography ; Heart Arrest/genetics/pathology ; Humans ; Infant ; KCNQ1 Potassium Channel/genetics ; KCNQ2 Potassium Channel/genetics ; Long QT Syndrome/*diagnosis/*genetics ; Middle Aged ; Mutation/*genetics ; NAV1.5 Voltage-Gated Sodium Channel/genetics ; Penetrance ; Potassium Channels, Inwardly Rectifying/genetics ; Republic of Korea ; Risk Factors ; Seizures/genetics/pathology ; Young Adult

PURPOSE: The use of implantable cardioverter defibrillators (ICDs) to prevent sudden cardiac death is increasing in children and adolescents. This study investigated the use of ICDs in children with congenital heart disease. METHODS: This retrospective study was conducted on the clinical characteristics and effectiveness of ICD implantation at the department of pediatrics of a single tertiary center between 2007 and 2011. RESULTS: Fifteen patients underwent ICD implantation. Their mean age at the time of implantation was 14.5+/-5.4 years (range, 2 to 22 years). The follow-up duration was 28.9+/-20.4 months. The cause of ICD implantation was cardiac arrest in 7, sustained ventricular tachycardia in 6, and syncope in 2 patients. The underlying disorders were as follows: ionic channelopathy in 6 patients (long QT type 3 in 4, catecholaminergic polymorphic ventricular tachycardia [CPVT] in 1, and J wave syndrome in 1), cardiomyopathy in 5 patients, and postoperative congenital heart disease in 4 patients. ICD coils were implanted in the pericardial space in 2 children (ages 2 and 6 years). Five patients received appropriate ICD shock therapy, and 2 patients received inappropriate shocks due to supraventricular tachycardia. During follow-up, 2 patients required lead dysfunction-related revision. One patient with CPVT suffered from an ICD storm that was resolved using sympathetic denervation surgery. CONCLUSION: The overall ICD outcome was acceptable in most pediatric patients. Early diagnosis and timely ICD implantation are recommended for preventing sudden death in high-risk children and patients with congenital heart disease.
Adolescent ; Cardiomyopathies ; Channelopathies ; Child ; Convulsive Therapy ; Death, Sudden ; Death, Sudden, Cardiac ; Defibrillators ; Defibrillators, Implantable ; Early Diagnosis ; Follow-Up Studies ; Heart ; Heart Arrest ; Heart Defects, Congenital ; Heart Diseases ; Humans ; Korea ; Long QT Syndrome ; Pediatrics ; Retrospective Studies ; Shock ; Sympathectomy ; Syncope ; Tachycardia, Supraventricular ; Tachycardia, Ventricular