Intermittent left bundle branch block caused by coronary vasospasm

Abstract

Intermittent left bundle branch block (LBBB) has been reported in the literature following certain conditions such as cardiac blunt trauma, myocardial infarction (MI) or exercise induced LBBB. In the majority of cases, the patients usually have underlying coronary arteries disease. LBBB often prevents the electrocardiographic diagnosis of acute MI; therefore, new LBBB in the setting of chest pain is usually treated as transmural MI. We describe a case of patient who presented with intermittent LBBB associated with chest pain, and subsequently the patient was taken to the catheterization laboratory for emergency coronary angiogram, which revealed 80% spasm in left anterior descending artery, which was totally relieved by nitroglycerin infusion. No other significant CAD was noted.

Episodic Left Bundle Branch Block—A Comprehensive Review of the Literature

“…The underlying mechanism in such cases is suggested to be the microcirculatory ischemia or coronary vasospasm . In some instances, the chest pain due to episodic LBBB has been attributed to the sudden ventricular dysynchrony rather than to myocardial ischemia but coronary vasospasm may be the underlying cause in cases with normal coronary arteriograms . Very recently, Shvilkin et al.…”

A Case of Intermittent Left Bundle Branch Block

“…Intermittent LBBB is a rare occurrence. In literature, it has been reported with exercise, tachycardia, ischemic and hypertensive heart disease, hyperkalemia, drugs, anesthesia, pulmonary embolism, chest trauma, and cardiac interventional procedures [5,6]. Patients with intermittent LBBB may develop persistent LBBB; therefore, it is imperative to rule out reversible conditions and to follow them closely.…”

“…In intermittent LBBB, normal QRS alternates with bundle branch block pattern QRS. This 2:1 LBBB pattern is mostly associated with tachycardia, aortic stenosis, ischemic heart disease, blunt cardiac injury, dilated cardiomyopathy, infective endocarditis, digoxin toxicity, and anesthesia induction [5,6]. The management and prognosis of intermittent LBBB depend on the etiology along with the presence or absence of organic heart disease.…”

A new experimentally validated formula to calculate the QT interval in the presence of left bundle branch block holds true in the clinical setting

“…Intermittent intrinsic LBBB is a regularly described clinical entity. It can be induced by different mechanisms such as coronary artery stenosis (Kershaw & Rogers, ), coronary vasospasm (Alhaji, ), or myocardial contusion (Pizzo et al., ). Mostly, intermittent LBBB appears or disappears depending on heart rate.…”