Complete heart block revealing adrenal tuberculosis.

Complete heart block is a commonly encountered entity in clinical cardiology practice, which may be secondary to a variety of diseases including metabolic disorders. Here, we report the case of a 60-year-old female patient who presented with persistent symptomatic complete heart block despite the correction of electrolyte disorder and required admission for permanent pacemaker implantation. The etiologic investigation revealed underlying adrenal insufficiency due to tuberculosis. The clinical and biological presentation of adrenal insufficiency is variable with a difficult etiologic assessment. Although cardiac manifestations are rare, significant electrocardiographic abnormalities can be observed in untreated adrenal insufficiency, such as conduction abnormalities. Hence, in our case, we highlight one of the rare etiologies of conductive disorders and the complexity of the extrapulmonary manifestations of tuberculosis that clinicians should be aware of it.

Cystic Tumor of the Atrioventricular Node Causing Rapid-Onset and Reversible Complete Heart Block.

Cystic tumors of the atrioventricular node are rare primary cardiac neoplasms, frequently reported as a postmortem diagnosis during autopsy. Despite their small size, they can present with complete heart block or sudden cardiac death. Herein, we present a case of rapidly progressing high-grade atrioventricular block that improved after surgery. (Level of Difficulty: Intermediate.).

Fibrosing Mediastinitis Causing High Degree AV Block in a Young Female Patient.

A 30-year-old woman presented with presyncopal episodes and was found to have high degree atrioventricular block. Computed tomography imaging demonstrated pericardial thickening extending from the main pulmonary artery to the aortic cusps. Here we present a rare case of fibrosing mediastinitis causing high-degree atrioventricular block. (Level of Difficulty: Intermediate.).

Increased in vivo perpetuation of whole-heart ventricular arrhythmia in heterozygous Na+/Ca2+ exchanger knockout mice.

Aims: Na+/Ca2+ exchanger (NCX) upregulation in cardiac diseases like heart failure promotes as an independent proarrhythmic factor early and delayed afterdepolarizations (EADs/DADs) on the single cell level. Consequently, NCX inhibition protects against EADs and DADs in isolated cardiomyocytes. We here investigate, whether these promising cellular in vitro findings likewise apply to an in vivo setup. Methods/Results: Programmed ventricular stimulation (PVS) and isoproterenol were applied to a murine heterozygous NCX-knockout model (KO) to investigate ventricular arrhythmia initiation and perpetuation compared to wild-type (WT). KO displayed a reduced susceptibility towards isoproterenol-induced premature ventricular complexes. During PVS, initiation of single or double ectopic beats was similar between KO and WT. But strikingly, perpetuation of ventricular tachycardia (VT) was significantly increased in KO (animals with VT - KO: 82 %; WT: 47 %; p = 0.0122 / median number of VTs - KO: 4.5 (1.0, 6.25); WT: 0.0 (0.0, 4.0); p = 0.0039). The median VT duration was prolonged in KO (in s; KO: 0.38 (0.19, 0.96); WT: 0.0 (0.0, 0.60); p = 0.0239). The ventricular refractory period (VRP) was shortened in KO (in ms; KO: 15.1 ± 0.7; WT: 18.7 ± 0.7; p = 0.0013). Conclusions: Not the initiation, but the perpetuation of provoked whole-heart in vivo ventricular arrhythmia was increased in KO. As a potential mechanism, we found a significantly reduced VRP, which may promote perpetuation of reentrant ventricular arrhythmia. On a translational perspective, the antiarrhythmic concept of therapeutic NCX inhibition seems to be ambivalent by protecting from initiating afterdepolarizations but favoring arrhythmia perpetuation in vivo at least in a murine model.

Ventriculoatrial Block and His-His Changes During Supraventricular Tachycardia: Diagnostic and Mechanistic Implications.

Supraventricular tachycardia (SVT) with ventriculoatrial (VA) block can represent a diagnostic challenge. We present a case of SVT where His-His interval shortening was repeatedly observed during episodes of VA block. This novel observation is more diagnostically suggestive of atrioventricular nodal re-entrant tachycardia, as opposed to orthodromic re-entry using a nodofascicular or nodoventricular pathway where a constant His-His is recorded during episodes of VA block. (Level of Difficulty: Intermediate.).

Narrow Complex Tachycardia With Intermittent 2:1 Atrioventricular Relationship.

Narrow QRS complex tachycardia has a broad differential diagnosis. We present a series of rhythm strips with representative onset, transition from 2:1 AV conduction to 1:1 AV conduction, and offset of tachycardia. By analyzing these rhythm strips, we can identify the electrophysiologic mechanism and diagnosis. (Level of Difficulty: Intermediate.).

Sinus Node Artery Occlusion During Cardiac Denervation Procedures.

Cardioneural ablation is a novel treatment for functional bradycardia. However, the risk of acute complications is still unknown. The aim of this case report is to describe acute occlusion of the sinus node artery after cardiac denervation procedures in 2 patients and to encourage measures to prevent it, such as evaluating the aortic angulation in older patients before the procedure and by monitoring signs of sinus failure during ablation in patients with electroanatomical maps showing a constricted aspect of the right atrium. (Level of Difficulty: Advanced.).

Maternal Anti-Ro/SSA Autoantibodies and Prolonged PR Interval in a Competitive Athlete: Beyond Training-Induced Electrical Remodeling.

Prolongation of the PR interval is common among competitive athletes. However, further investigations should be performed when the PR interval is markedly prolonged. We report the case of a young male athlete with an autoimmune-mediated atrioventricular block due to circulating anti-Ro/SSA-antibodies in the mother (late progressive congenital form). (Level of Difficulty: Advanced.).

CLInical Profile and Side Effects of chronic use of oral Amiodarone in cardiology outpatients department (CLIPSE-A Study)- A prospective observational study.

Background: Amiodarone belongs to Class-III anti-arrhythmic drugs. It is one of the most effective anti-arrhythmic drugs used to treat or prevent several types of arrhythmias including atrial fibrillation, atrial flutter, ventricular tachycardia, and wide complex tachycardia, but unfortunately carries a high toxicity profile. Also, side effects of amiodarone involving various organs can be life-threatening. Materials & methods: This was an observational study carried out for six months i.e from April to September. The study included patients who are on amiodarone for greater than or equal to six months. The required data was collected in-person from the case sheets, treatment charts, and by interviewing the patients. The data for 67 patients was documented in suitable data collection form for analysis. Results: From our study data, it was noted that amiodarone was used for 3 different indications-atrial fibrillation, atrial flutter, and ventricular tachycardia. Among 67 patients enrolled, 38 had no side-effects. Side-effects data in the rest grouped basing on the organ system affected: 9 patients had renal effects, 6 patients had ophthalmic effects, 4 patients had endocrine effects, and 5 patients had hepatic effects. Conclusion: From our study, it is concluded that amiodarone is a safe and effective anti-arrhythmic drug at lower doses i.e. 200-1100 mg/week. When treated in lower doses of 1400-2800 mg/week, many side effects have been incident. Although these effects are mild and develop only after prolonged usage of the drug, it should be used judiciously.

Treatment of Symptomatic Functional Atrioventricular Block by Cardioneuroablation as an Alternative to Pacemaker Implantation.

A woman with recurrent presyncope caused by a functional atrioventricular (AV) block after meals, with limiting symptoms, underwent cardioneuroablation and AV node vagal denervation without pacemaker implantation. Normal AV conduction was recovered with complete abolishment of symptoms. (Level of Difficulty: Advanced.).

Coexisting Thyroiditis and Carditis in a Patient With Lyme Disease: Looking for a Unifying Diagnosis.

Background/Objective: Lyme disease, the most common vector-borne infection in the United States, causes multisystem inflammation. We describe a patient who presented with symptoms of Lyme disease, carditis, and thyroiditis. Case Report: A 53-year-old woman developed fatigue and dyspnea on exertion 1 month after returning from a trip to Delaware. Her electrocardiogram (ECG) showed first-degree atrioventricular (AV) block with a P-R interval up to 392 milliseconds, in the setting of elevated free thyroxine and undetectable thyroid-stimulating hormone levels. Lyme serology was positive. She was hospitalized and started on ceftriaxone. During the second day of hospitalization, AV block worsened to second-degree Mobitz type II but converted back to first-degree AV block after a few hours. Her 24-hour I-123 thyroid uptake and scan revealed markedly diminished I-123 uptake of 1.2%. On day 4, the P-R interval improved, and she was discharged on doxycycline for 3 weeks. P-R interval on ECG and repeated thyroid function tests were normal after finishing antibiotic treatment. Discussion: In our patient, known exposure to the vector, a classic rash on the chest, improvement in the symptoms, and normalization of thyroid function tests after antibiotic therapy support Lyme infection as a cause of carditis and painless, autoimmune thyroiditis. Conclusion: Our case highlights the importance of considering Lyme disease as a cause of painless, autoimmune thyroiditis, especially in patients with concurrent cardiovascular involvement.

Transcatheter Systemic AV Valve-in-Valve Implantation in a Patient With LTGA and Ebstein Anomaly.

We present the first in-human transcatheter systemic atrioventricular valve-in-valve implantation in a 37-year-old patient with Ebstein anomaly, levo-transposition of the great arteries, and prior systemic valve replacement. She had severe bioprosthetic valve regurgitation and reduced systolic function. She had high surgical risk and was planned for transcatheter intervention. (Level of Difficulty: Advanced.).

Pacemaker Explantation in Patients With Lyme Carditis.

Early recognition of Lyme carditis is critical to preventing unnecessary pacemaker implantation for conduction abnormalities associated with this tick-born infection. Patients who do receive a pacemaker should be considered for device extraction after the completion of their antibiotic therapy if they recover normal atrioventricular node conduction. (Level of Difficulty: Intermediate.).

Multiple QRS Morphologies: Findings on an Initial Newborn ECG.

Regular wide complex tachycardia carries with it a standard array of differential diagnoses. This electrocardiogram demonstrates wide complex tachycardia and multiple QRS configurations in a neonate without structural heart disease with an uncommon suspected underlying diagnosis. (Level of Difficulty: Advanced.).

Acute STEMI Due to Severe Triple-Vessel Spasm After IV Adenosine Injection During Cryo-Balloon Isolation.

Adenosine IV is commonly used after pulmonary vein isolation to check for dormant electrical conduction. Herein, we present the case of a 60-year-old patient who exhibited marked hypotension, conduction abnormalities, and ST-segment elevation after routine adenosine injection. Coronary angiography revealed diffuse coronary spasm that was successfully treated with intracoronary nitroglycerin. (Level of Difficulty: Intermediate.).

Acute Coronary Syndrome Requiring Coronary Artery Bypass Grafting in a Patient With Sotos Syndrome.

Sotos syndrome, characterized by cerebral gigantism with neurologic disorders, is an overgrowth syndrome caused by mutations of the NSD1 gene, with an estimated prevalence of 1:10,000-1:50,000. We herein describe the first case of Sotos syndrome complicated by acute coronary syndrome, for which emergency coronary artery bypass grafting was performed. (Level of Difficulty: Intermediate.).

Electrophysiological Manifestations of Cardiac Amyloidosis: JACC: CardioOncology State-of-the-Art Review.

Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy caused by the extracellular deposition of amyloid fibrils in the myocardium. Although cardiac amyloidosis patients primarily present with heart failure symptoms, arrhythmias and conduction system disease are frequently encountered. Atrial fibrillation (AF) is observed in up to 70% of patients at the time of diagnosis, and patients typically have controlled ventricular rates caused by concomitant conduction system disease. Thromboembolic risk is particularly high in patients with CA and AF, and left atrial thrombi have been observed even in the absence of clinically diagnosed AF. Atrioventricular nodal and infra-Hisian disease are common, and permanent pacemakers are frequently required. The use of implantable cardioverter-defibrillators in this population is controversial. This review summarizes the published data and therapeutic strategies surrounding arrhythmias and conduction system disease with the goal of aiding clinicians managing the clinical complexities of CA.

Left ventricular vortex analysis by high-frame rate blood speckle tracking echocardiography in healthy children and in congenital heart disease.

BACKGROUND: High-frame rate blood speckle tracking (BST) echocardiography is a new technique for the assessment of intracardiac flow. The purpose of this study was to evaluate the characteristics of left ventricular (LV) vortices in healthy children and in those with congenital heart disease (CHD). METHODS: Characteristics of LV vortices were analyses based on 4-chamber BST images from 118 healthy children (median age 6.84 years, range 0.01-17 years) and 43 children with CHD (median age 0.99 years, range 0.01-14 years). Both groups were compared after propensity matching. Multiple linear regression was used to identify factors that independently influence vortex characteristics. RESULTS: Feasibility of vortex imaging was 93.7% for healthy children and 95.6% for CHD. After propensity matching, there were no overall significant differences in vortex distance to apex, distance to interventricular septum (IVS), height, width, sphericity index, or area. However, multiple regression analysis revealed significant associations of LV morphology with vortex characteristics. Furthermore, CHD involving LV volume overload and CHD involving LV pressure overload were both associated with vortices localized closer to the IVS. CONCLUSIONS: LV vortex analysis using high-frame rate BST echocardiography is feasible in healthy children and in those with CHD. As they are associated with LV morphology and are modified in some types of CHD, vortices might yield diagnostic and prognostic value. Future studies are warranted to establish applications of vortex imaging in the clinical setting.

ECG in an Athlete With Syncope: Innocuous Incomplete Right Bundle Branch Block or Brugada Pattern?

Abnormalities of an athlete's electrocardiogram may be the result of an underlying heart disease and may carry a risk of sudden death. It is important that electrocardiographic abnormalities are correctly distinguished. We present the case of a young marathon athlete presenting with syncope and incomplete right bundle block pattern suggestive of a type 2 Brugada pattern. (Level of Difficulty: Advanced.).