Challenges in the Diagnosis and Acute Management of Idiopathic Left Ventricular Tachycardia : A Case Report
Author : D. A. S. Ratnasari, I. A. Kusuma
Upload Date : 19-04-2018
Introduction: Idiopathic Left Ventricular Tachycardia (ILVT) is a ventricular tachycardia characterized by right bundle branch block (RBBB) and left axis deviation (LAD) on electrocardiogram. It occurs predominantly in young males (15–40 years old) without structural heart disease. It is important for emergency physicians to recognize the electrocardiographic features of ILVT and to manage these patients appropriately.
Case Description: A 32-year-old male presented to the hospital with a sudden onset of palpitations and chest discomfort. He had three similiar episodes previously. On presentation, the patient was hemodynamically stable. However, his initial electrocardiogram displayed a wide-complex tachycardia, a ventricular rate of 190 beats/minute, with RBBB morphology and LAD. Unsuccessful attempts were made to convert the patient to sinus rhythm with vagal maneuvers and diltiazem infusion. The patient then felt dizziness and his blood pressure declined to 79/58 mmHg. Syncronized cardioversion performed immediately with energy of 100 Joule, and the rhythm was convert. Verapamil 80 mg twice daily was given, and he planned to radiofrequency ablation.
Discussion: ILVT typically presents in male young adults with the most frequent clinical presentation is paroxysmal episodes of palpitations, dizziness and, less frequently, syncope. The electrocardiographical pattern varies depending on the site of origin of the tachycardia. Posterior fascicular ventricular tachycardia (P-ILVT) accounts for the 90-95% of cases. P-ILVT is electrocardiographically characterised by RBBB morphology and LAD. Our patient came with palpitations, and the ECG showed VT with RBBB type and LAD, so we diagnosed as P-ILVT. As in other cases of wide QRS tachycardia, we should evaluate the hemodynamic status of the patient. In stable patients, first line treatment is calcium channel blockers. This has been attributed to the fact that ILVT depends on the slow entry of calcium in partially depolarised Purkinje fibers. Electrical cardioversion is emergent in case of tachycardia intolerance. Our patient came with stable haemodynamic, so he got diltiazem IV. But his blood pressure then declined, so we performed electrical cardioversion. His rhythm converted to sinus, and we gave verapamil twice daily. Verapamil may be helpful in patients with mild symptoms. When symptoms are severe and pharmacologic treatment is not effective or is poorly tolerated, catheter ablation is recommended. Ablation success rates as reported in various series vary between 85 and 95%, and are generally higher in those patients with P-ILVT.
Conclusion: Awareness have to be roused among emergency physicians that patient will often present with VT making it difficult to diagnose and manage. ILVT typically presents in male young adults and sensitive with calcium channel blocker therapy. Electrical cardioversion should be done if the patient has unstable haemodynamic.
KEYWORDS : idiopathic left ventricular tachycardia, synchronized cardioversion, verapamil