Bidirectional ventricular tachycardia in cardiac sarcoidosis

Bidirectional Ventricular Tachycardia with Stress-Induced Cardiomyopathy

Bidirectional ventricular tachycardia (BDVT) is a rare electrocardiographic finding characterized by rapid, wide complex, alternating QRS morphology with 180-degree swings in the frontal plane axis or, less commonly, alternating right bundle branch and left bundle branch block morphology. The most proposed mechanisms for BDVT involve triggered activity or enhanced automaticity resulting from calcium dysregulation. Catecholamine surge can cause myocardial injury as well as calcium dysregulation resulting in enhanced automaticity that can lead to arrhythmias such as BDVT. This case report stands to describe a unique presentation of BDVT and stress-induced cardiomyopathy, resulting from catecholamine surge following multiple traumatic gunshot wounds in the setting of methamphetamine use.

Bidirectional Ventricular Tachycardia in a Patient With Fulminant Myocarditis Secondary to Cardiac Sarcoidosis Mimicking Giant Cell Myocarditis

Differentiating between sarcoidosis and giant cell myocarditis (GCM) based on clinical presentation is difficult. We present the case of a 57-year-old woman who was initially diagnosed with GCM based on endomyocardial biopsy. The patient was refractory to standard management for GCM and went on to develop bidirectional ventricular tachycardia, a finding suggestive of sarcoidosis. Unfortunately, the patient eventually needed cardiac transplantation. The explanted heart demonstrated cardiac sarcoidosis. Bidirectional ventricular tachycardia has not been demonstrated in GCM, and its presence may help in distinguishing between GCM and cardiac sarcoidosis.

Andersen-Tawil Syndrome: A Comprehensive Review

Andersen-Tawil syndrome (ATS) is a very rare orphan genetic multisystem channelopathy without structural heart disease (with rare exceptions). ATS type 1 is inherited in an autosomal dominant fashion and is caused by mutations in the KCNJ2 gene, which encodes the α subunit of the K+ channel protein Kir2.1 (in ≈ 50-60% of cases). ATS type 2 is in turn linked to a rare mutation in the KCNJ5-GIRK4 gene that encodes the G protein-sensitive-activated inwardly rectifying K+ channel Kir3.4 (15%), which carries the acetylcholine-induced potassium current. About 30% of cases are de novo/sporadic, suggesting that additional as-yet unidentified genes also cause the disorder. A triad of periodic muscle paralysis, repolarization changes in the electrocardiogram, and structural body changes characterize ATS. The typical muscular change is episodic flaccid muscle weakness. Prolongation of the QU/QUc intervals and normal or minimally prolonged QT/QTc intervals with a tendency to ventricular arrhythmias are typical repolarization changes. Bidirectional ventricular tachycardia is the hallmark ventricular arrhythmia, but also premature ventricular contractions, and rarely, polymorphic ventricular tachycardia of torsade de pointes type may be present. Patients with ATS have characteristic physical developmental dysmorphisms that affect the face, skull, limbs, thorax, and stature. Mild learning difficulties and a distinct neurocognitive phenotype (deficits in executive function and abstract reasoning) have been described. About 60% of affected individuals have all features of the major triad. The purpose of this review is to present historical aspects, nomenclature (observations/criticisms), epidemiology, genetics, electrocardiography, arrhythmias, electrophysiological mechanisms, diagnostic criteria/clues of periodic paralysis, prognosis, and management of ATS.

Bidirectional Ventricular Tachycardia in a Women with Dilated Cardiomyopathy: A Case Report

Introduction:

Bidirectional ventricular tachycardia (BVT) is a rare arrhythmia characterized by QRS complexes with an axis in the frontal plane alternating polarity in the precordial leads and right bundle branch block (RBBB) morphology. To the best of our knowledge, there is no previous report in dilated cardiomyopathy or in the context of a probable peripartum cardiomyopathy.

Case Presentation:

A 26-year-old, 9-month female patient, with no significant past medical history (the patient denies medication intake, herbs like aconite, trouble during delivery, any heart issues or family history of sudden death or cardiomyopathies) who presents to the emergency room due to 11 days of dyspnea, exacerbated by daily activities, orthopnea, and paroxysmal nocturnal dyspnea. She presented with ventricular bigeminy and systolic dysfunction with left ventricular ejection fraction (LVEF) <20%. The patient later developed a stable ventricular tachycardia (VT) treated with amiodarone, which resulted in hemodynamic instability and BVT rhythm with VT paroxysms. Without the possibility of ablation, the use of high dose beta blockers and an implantable cardioverter defibrillator resulted in the same rhythm with a lower heart rate, better NYHA functional class, and less episodes of VTs.

Conclusion:

BVT is a rare type of tachycardia that can be present in dilated cardiomyopathy. In the absence of ablation capabilities, decreasing the heart rate with beta-blockers may reduce the rate of paroxysmal VTs.

Left Ventricular Aneurysm Presenting as Bidirectional Ventricular Tachycardia

Background

Bidirectional ventricular tachycardia is a rare form of ventricular arrhythmia, characterized by a changing of the mean QRS axis of 180 degrees. Digitalis toxicity is the most common cause of bidirectional ventricular tachycardia; other causes include myocarditis, aconite toxicity, metastatic cardiac tumor, myocardial infarction, and cardiac channelopathies.

Case Report

A 73-year-old male with hypertension and a pacemaker implanted for sick sinus syndrome presented with a complaint of substernal chest pressure for several days. He also stated he had had an episode of near syncope. The patient's physical examination was unremarkable; however, electrocardiogram demonstrated sustained bidirectional ventricular tachycardia. Echocardiogram showed severe anterior wall hypokinesis and an estimated ejection fraction of 35%, as well as an apical ventricular aneurysm. Electrophysiology study showed that the apical ventricular aneurysm was the site of the bidirectional arrhythmia. The patient was successfully treated with ventricular tachycardia ablation.

Conclusion

This case is a unique example of a patient with bidirectional ventricular tachycardia originating from an apical left ventricular aneurysm that was treated successfully by ablation.