Bidirectional Ventricular Tachycardia in Acute Multivessel Myocardial Infarction.

ABSTRACT

Bidirectional ventricular tachycardia (BVT) is a rare and unusual ventricular dysrhythmia that is characterized by a beat-to-beat alternation of the QRS axis. This can sometimes manifest as alternating left and right bundle branch blocks. To the best of our knowledge, there are two previous cases of BVT in the setting of type I myocardial infarction. Our case would be the third and showed a subtle change in the anterior-posterior axis that can be seen in lead V2. The coronary angiography of our patient demonstrated severe multivessel coronary artery disease with complete total occlusion of the proximal dominant right coronary artery, 100% in-stent restenosis of the ostial left circumflex, 40% stenosis of left main, and 90% stenosis of mid left anterior descending artery (LAD). The BVT resolved after two amiodarone boluses followed by a drip. We attempted to transition to oral mexiletine, however, the patient was unable to tolerate the medication due to intractable nausea and vomiting. The patient subsequently underwent high risk coronary artery bypass graft surgery with no further episodes of BVT following revascularization and was discharged after six weeks of hospitalization. Although rare, type I myocardial infarction is an important differential diagnosis of BVT.