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Background: Catecholaminergic polymorphic ventricular tachycardia is an uncommon, potentially lethal, ion channelopathy. Standard therapies have high failure rates and little is known about treatment in children. Newer options such as flecainide and left cardiac sympathetic denervation are not well validated. We sought to define treatment outcomes in children with catecholaminergic polymorphic ventricular tachycardia., Methods and Results: This is a Pediatric and Congenital Electrophysiology Society multicenter, retrospective cohort study of catecholaminergic polymorphic ventricular tachycardia patients diagnosed before 19 years of age. The cohort included 226 patients, including 170 probands and 56 relatives. Symptomatic presentation was reported in 176 (78%). Symptom onset occurred at 10.8 (interquartile range, 6.8-13.2) years with a delay to diagnosis of 0.5 (0-2.6) years. Syncope (P<0.001), cardiac arrest (P<0.001), and treatment failure (P=0.008) occurred more often in probands. β-Blockers were prescribed in 205 of 211 patients (97%) on medication, and 25% experienced at least 1 treatment failure event. Implantable cardioverter defibrillators were placed in 121 (54%) and was associated with electrical storm in 22 (18%). Flecainide was used in 24% and left cardiac sympathetic denervation in 8%. Six deaths (3%) occurred during a cumulative follow-up of 788 patient-years., Conclusions: This study demonstrates a malignant phenotype and lengthy delay to diagnosis in catecholaminergic polymorphic ventricular tachycardia. Probands were typically severely affected. β-Blockers were almost universally initiated; however, treatment failure, noncompliance and subtherapeutic dosing were often reported. Implantable cardioverter defibrillators were common despite numerous device-related complications. Treatment failure was rare in the quarter of patients on flecainide. Left cardiac sympathetic denervation was not uncommon although the indication was variable., (© 2015 American Heart Association, Inc.)

Sudden cardiac death (SCD) in an athlete is a rare but tragic event, and significant controversy exists regarding the most effective method to define those at highest risk. Recommendations of the American Heart Association require that a history and physical examination be used for preparticipation screening with an abnormal cardiac finding expected to prompt further evaluation. Given the lack of data documenting that electrocardiogram (ECG) screening in all competitive athletes is either feasible or appropriate, these same guidelines state that such screening is optional but not mandatory. The extremely low incidence of SCD events, in conjunction with the low sensitivity and specificity of ECG as a screening tool in athletes, contributes to this recommendation. Although these guidelines target all competitive athletes, however, there may be subgroups of athletes, based on age, level of competition, individual sport, or state of residence, for which mandatory ECG screening may be both appropriate and sensible. Given the lack of resolution of the ongoing ECG debate, it is perhaps reasonable to consider screening specific high-risk subgroups of athletes rather than continuing to dispute whether to screen all competitive athletes or none at all. Recent data suggest that such a program may be feasible and may provide a rationale basis for subsequent expansion of cardiovascular screening programs.

Assessment of the risk for sudden cardiac death (SCD) after surgery for congenital heart disease (CHD) remains a difficult challenge. In the study of this problem, the focus has evolved from concern regarding late-onset heart block to a subsequent focus on ventricular and reentrant atrial arrhythmias, with the most recent emphasis on ventricular dysfunction and heart failure. Sudden cardiac death in CHD patients has been studied most extensively in tetralogy of Fallot. More than 30 risk factors have been proposed, with age at repair, QRS duration, right ventricular enlargement, and left ventricular dysfunction considered the most predictive risk factors. Additionally, SCD has been studied in patients with atrial repair for transposition of the great arteries, left heart obstructive lesions, and to a limited extent, patients with univentricular physiology. This review discusses current risk factors for SCD in CHD and the limited positive predictive value of any individual factor. The emphasis is on contemporary patients with CHD, who differ markedly from those who had repair of CHD decades earlier. This is characterized by complete repairs during the neonatal period, improved physiologic outcomes, and extended survival of patients with complex forms of CHD. Therefore, earlier data and conclusions may not be relevant to newer generations of patients with CHD. According to current perspectives, systemic ventricular dysfunction becomes a major risk factor beyond the age of 20 years. The first symptomatic arrhythmia may result in SCD, and defibrillators are increasingly implanted despite the lack of risk stratification criteria. The large number of potential risk factors and therapeutic options, in contrast to the low incidence of actual events, results in a difficult clinical challenge in the assessment of the risk for SCD in the individual patient with CHD.

Purpose of Review: Sudden cardiac death (SCD) is a rare but tragic event in children. This review highlights the important advances in this field during the last year, both in the understanding of the underlying diseases and in improvements in the management of patients at risk for SCD., Recent Findings: The study of SCD has focused on several major themes: progress in understanding the causes and treatments of genetic cardiovascular diseases, improved management of patients with congenital heart disease with SCD risk, treatment strategies for SCD risk reduction in patients with cardiomyopathies, and defining guidelines for athletic preparticipation screening., Summary: With advances in understanding of the causes and risk factors for SCD, management of children at risk for SCD continues to improve. This includes improved clinical criteria for identifying SCD risk as well as optimizing management strategies such as exercise restriction, antiarrhythmic medications, and implantable cardioverter defibrillator therapy.