HRCR Rare Diseases Article Collection
Demonstration of presence of a sling between anterior and posterior bundle branch during tachycardia using twin atrioventricular nodes: A case of asplenia syndromeAtrioventricular (AV) reciprocating tachycardia via twin AV nodes and corresponding AV bundles with a connecting sling has been reported in patients with asplenia and right isomerism.1,2 Although the presence of the sling has been reported histologically,3 its connection form and electrophysiological properties remain to be elucidated.
Very delayed pericarditis associated with ethanol ablation of the vein of Marshall for treatment of atrial fibrillationCatheter ablation of persistent atrial fibrillation has limited success. Procedural strategies beyond pulmonary vein isolation have failed to consistently improve results.
Multiple recurrent episodes of pacemaker-associated postcardiac injury syndromePostcardiac injury syndrome (PCIS) is an autoimmune disease that causes damage to the pericardium, myocardium, and pleura after myocardial infarction, cardiac surgery, or trauma. Although most cases are benign, anti-inflammatory agents may be used to treat PCIS. Rarely, PCIS may become refractory or recur after anti-inflammatory treatment.1 In such cases, long-term oral corticosteroids are usually prescribed2; however, the optimal duration of administration remains unclear. We report a patient who experienced multiple recurrent episodes of pacemaker lead–related PCIS that were treated with oral prednisone and pericardial drainage.
Idiopathic premature ventricular contraction–triggered ventricular fibrillation: Subcutaneous implantable cardioverter-defibrillator (S-ICD) template matched ablation in the absence of inducible clinical premature ventricular contractionIdiopathic ventricular fibrillation is diagnosed in patients who have survived sudden cardiac arrest from ventricular fibrillation (VF) without identifiable structural heart disease.1 It is the main cause of unexplained sudden cardiac death, particularly in young patients under the age of 35.2 An implantable cardioverter-defibrillator (ICD) is usually recommended for the secondary prevention of sudden cardiac death. VF ablation is recommended for clinical VF recurrence and for reducing the number of ICD shocks.
An unexpected finding by epicardial mapping: Atrial fibrillation in a 14-month-old patient with short QT syndromeShort QT syndrome (SQTS) is a very rare channelopathy accompanied by familial clustering and sudden cardiac death.1 It has an estimated prevalence ranging from 0.02% up to 2% in the adult population, but only 0.05% among pediatric patients.2–6 To date, 9 mutations in 6 different genes have been identified, including KCNH2, KCNQ1, KCNJ1, CACNA1C, CACNB2, and CACNA2D1. In pediatric patients, SQTS is characterized by shortening of the corrected QT interval (QTcB <316 ms, J-Tpeak cB <181 ms, and the presence of early repolarization) on the surface electrocardiogram (ECG).
Right ventricular outflow tract ablation close to an anomalous right coronary artery: When imaging meets electrophysiologyCatheter ablation is a commonly undertaken and highly effective treatment for symptomatic right ventricular outflow tract (RVOT) ventricular ectopy / ventricular tachycardia (VT).1 Despite the high chance of cure with ablation, caution is required to avoid collateral injury to coronary arteries in certain well-described locations. Anomalous coronary arteries are rare2 and may have an unfamiliar path involving the outflow tracts, posing a significantly increased risk with ablation. The approach to outflow tract ablation in a patient with an anomalous coronary artery has not been previously reported.
Novel trans-2,3-enoyl-CoA reductase–like variant associated with catecholaminergic polymorphic ventricular tachycardia type 3Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmia syndrome characterized by polymorphic ventricular tachycardia, usually provoked by emotional stress or exercise, in the absence of any structural cardiac abnormality, and in the presence of often normal resting electrocardiogram (ECG).1 It is a highly lethal disease with an overall mortality of 30%–40% if left untreated.2 Studies have shown that almost 35% of affected individuals become symptomatic before the age of 10 and 75% before the age of 20 years.