HRCR Rare Diseases Article Collection
Takotsubo cardiomyopathy and Brugada syndrome in a patient with a novel loss-of-function variant in the cardiac sodium channel Nav1.5
Takotsubo cardiomyopathy (TTC) is a stress cardiomyopathy characterized by transient left ventricular dysfunction.1 TTC typically presents in postmenopausal women and is triggered by physical or emotional stress, most likely owing to an increased sympathetic activity.1 Symptoms resemble those of an acute myocardial infarction and the patients often present with various electrocardiogram (ECG) changes proposing an alteration in cardiac repolarization.2 Previously, familial clustering of TTC has been described, suggesting a genetic predisposition to TTC.Exercise-induced Brugada syndrome type 1 pattern
Brugada syndrome (BrS) is an inherited disorder usually afflicting patients with otherwise structurally normal hearts. Many triggers have been identified that can result in the phenotypic expression of the higher-risk BrS type 1 pattern. These triggers include but are not limited to fever, heightened vagal tone, and sodium (Na) channel blocking agents. Conversion to the type 1 pattern during exercise is unusual and in fact isoproterenol is a treatment for ventricular tachycardia (VT) storm in Brugada syndrome.Unmasked type 1 Brugada ECG pattern without a fever after a COVID-19 vaccination
Brugada syndrome (BrS) patients are regarded as a high-risk population under the COVID-19 pandemic because infection-induced fevers may unmask a type 1 Brugada electrocardiogram (ECG) pattern potentially leading to lethal ventricular arrhythmias.1 Vaccinations seem to be crucial in BrS patients; however, careful observation and antipyretic drugs are necessary for vaccine-induced fevers.2 Among the enormous number of COVID-19 vaccinations around the world, although the incidence is rare, death events, including sudden cardiac death, after a vaccination have been reported.Ventricular tachycardia ablation in a patient with Ehlers-Danlos syndrome
Ventricular tachycardia (VT) is a well-recognized complication of postinfarct-related scar. Catheter ablation is a guideline-recommended therapy in patients with frequent VT episodes. Ablation aims to target regions of slow conduction within ventricular scar that support reentry.1Late-onset Fabry disease revealed by ventricular tachycardia: A case report
Fabry disease (FD) is an X-linked lysosomal storage disorder due to mutations in the GLA gene leading to deficiency of lysosomal α-galactosidase A (α-Gal A). Classic FD causes multiorgan failure, whereas the later-onset phenotype is characterized by predominantly cardiac manifestations. Ventricular arrhythmias are among the complications.1,2Cardiac sarcoidosis involving the papillary muscle: A case report
Sarcoidosis is a granulomatous multisystem disease that is thought to arise from a dysregulated immunological response. A total of 25% of those suffering from sarcoidosis have cardiac involvement on postmortem analysis, but it is clinically apparent in only 5%.1 Isolated cardiac sarcoidosis (CS) has also been described.2 It may manifest as conduction system dysfunction, ventricular arrhythmias, congestive cardiac failure, or sudden cardiac death.3 CS has a predilection for the ventricular myocardium and its clinical presentation may vary from no symptoms to sudden cardiac death.Malignancies masquerading as device pocket infections
Infectious complications following cardiac implantable electronic device (CIED) implantation are associated with significant mortality. Establishing the correct diagnosis is important and not all presumed CIED pocket infections turn out to be infections. Rare cases of malignancy mimicking a pocket infection have been described. We present 2 cases of malignancy, initially thought to be a primary CIED pocket infection.A diagnostic dilemma upon discovery of a left atrial mass using an intracardiac echocardiogram
It is important to discern the nature of any mass that may appear on the left atrial (LA) ridge, or “coumadin ridge,” which is situated between the LA appendage and the left superior pulmonary vein prior to any procedures involving the left atrium. Despite the rarity of the appearance of LA ridge mass, the shape and location are important in distinguishing a cardiac tumor or thrombus.1 In this case report, a mass on the LA ridge was discovered during an intracardiac echocardiogram prior to transseptal puncture for ablation of atrial fibrillation, posing a diagnostic dilemma and leading to a cascade of imaging studies.Ventricular fibrillation due to a likely pathogenic SOS1 variant: An unrecognized etiology of infantile sudden death?
We present the case of a female infant presenting after a ventricular fibrillation arrest found to have ectopic atrial tachycardia (EAT). Evaluation revealed a likely pathogenic variant in SOS1 not previously reported in affected individuals. SOS1 variants are associated with Noonan syndrome, which belongs to a family of related genetic syndromes affecting the RAS/MAPK signaling pathway. To date, this is the first case reported of a ventricular fibrillation arrest in a patient with a RASopathy-related variant prior to development of the typically associated structural cardiac phenotype and may represent a previously unrecognized etiology of sudden death during infancy.Increased device thresholds with subsequent improvement status post–systemic therapy in a patient with multiple myeloma
The pacemaker device stimulation threshold by definition is the minimal amount of electrical energy required to induce consistent capture outside the refractory period of the heart. The difference between the threshold and the programmed device output reflects the reserve or pacing safety factor.1 It is affected by a multitude of factors, including physiologic variants, use of certain pharmacologic agents, and pathologies such as hypoxia, hypothermia, poorly controlled diabetes, and myocardial ischemia.Leadless atrioventricular synchronous pacing in Eisenmenger syndrome
Eisenmenger syndrome is at the extreme end of the phenotypic spectrum of pulmonary arterial hypertension associated with congenital heart disease. Over time, a large nonrestrictive left-to-right shunt provokes progressive pulmonary vascular disease that results in the shunt becoming bidirectional or reversing direction (ie, right-to-left). When the need for pacing arises, transvenous leads are generally considered contraindicated owing to a prohibitively high risk of paradoxical thromboembolism.A case of cardiac sarcoidosis with concurrent myocardial ischemia
Sarcoidosis is a rare multisystem disease of unknown etiology affecting 10–40 in 100,000 population, characterized by granulomatous inflammation.1 It has a diverse set of presentations ranging from diffuse to localized disease and can have either acute or chronic clinical course with multiple organ involvement.1 Classically, lungs are the most commonly affected organ, but systemic, dermatologic, and cardiac involvement also occur. Specifically, 20%–30% of sarcoidosis patients have been observed to have cardiac involvement in an autopsy1; however, only about 5% have a symptomatic presentation with cardiac disease.Ventricular tachycardia as the initial presentation of missed Kawasaki disease in a teenager
Ventricular tachycardia (VT) has been reported in acute cases of Kawasaki disease. VT secondary to ischemic sequelae is also a known long-term complication of Kawasaki disease, typically seen 2 decades after initial disease onset.1,2 We report the first case, to our knowledge, of an otherwise healthy teenager with sustained VT as the presenting symptom for missed Kawasaki disease and describe the management approach by our team that had not considered Kawasaki disease in the differential. This case broadens our understanding of Kawasaki disease presentations in the young and timing of long-term sequelae.Parahisian pacing to unmask Brugada pattern with concomitant left bundle branch block and to document epicardial ablation endpoint in Brugada syndrome
Brugada syndrome, traditionally described as a channelopathy affecting transmembrane sodium current, has been recognized as a structural disease affecting the epicardial right ventricular outflow tract (RVOT).1–3 This observation has been the basis for successful arrhythmic substrate ablation in these patients, with resolution of the Brugada pattern in the anterior precordial leads reported as a reliable procedural endpoint.4,5 However, the typical precordial electrocardiogram (ECG) pattern is obscured in patients with concomitant left bundle branch block (LBBB),6 making this a challenging observation in such patients.Cardiac magnetic resonance imaging findings in primary arrhythmogenic left ventricular cardiomyopathy with cardiocutaneous phenotype—Carvajal syndrome
The current revised task force criteria for diagnosis of arrhythmogenic cardiomyopathy (ACM) includes only morphological criteria for right ventricle with no consideration for left ventricle criteria.1 However, accumulating evidence suggests increasing left ventricle involvement in ACM. One such phenotype is Carvajal syndrome, which is a primary left ventricle ACM that is inherited as a familial cardiocutaneous syndrome consisting of woolly hair, palmoplantar keratoderma, and cardiac involvement.Cardiac magnetic resonance imaging–negative cardiac sarcoidosis
Sarcoidosis is a multisystem inflammatory granulomatous disease of unknown etiology. Up to 55% of patients with systemic sarcoidosis have documented cardiac involvement.1 Albeit less common, cardiac manifestations can be the first clinical presentation of sarcoidosis. These include conduction disturbances, ventricular arrhythmias, heart failure, and sudden cardiac death, accounting for 13%–25% of sarcoidosis-related death.1 Initial diagnostic workup often requires comprehensive cardiac imaging, including echocardiography, cardiac magnetic resonance imaging (CMR), and 18F-FDG positron emission tomography (PET); nonetheless, the diagnosis of cardiac sarcoidosis remains challenging.
