Discussion
The normal course of coronary arteries is between the pericardium and
epicardium, the two most outer layers of the heart. However, if a
portion of epicardium is encased by myocardial fibers it is called
myocardial bridge. It can occur in any coronary artery but the most
commonly involved one is the left anterior descending artery (LAD); the
least commonly affected coronary arteries are left circumflex and right
coronary arteries.( 6,7)
It was previously considered as a benign cardiovascular anomaly, but
because of increasing evidences of its complications it is no more a
benign disease, in at least subset of patients. Although it is benign
and most patients are asymptomatic, some are complicated by stable or
unstable angina, vasospastic angina, acute coronary syndromes, AV
blocks, arrthytima, and sudden cardiac death. (8- 11)
It is not uncommon for the diagnosis of MB to be delayed. This could be
because of the varied clinical presentations, and lack of advanced
imaging modality in poor settings. Our patient visited several health
facilities before she was referred to our hospital, where the diagnosis
was made. This could be as a result of lack of awareness about the MB,
and unavailability of advanced imaging modalities.
Although there are cases reports of MB complications in young female
patients (12), most of these complications were observed in young male
patients. Our patient is a 38 years young female patient; this makes our
patient a unique.
MB induces acute coronary syndromes via several mechanisms including
coronary spasm, thrombosis, coronary dissection, or development of focal
atherosclerosis proximal to the myocardial bridging. (13)
Diagnosis of MB can differ significantly depending on the imaging
modality employed to identify these variants. The prevalent methods
frequently examined to ascertain prevalence in the general population
comprise coronary angiography (CA), coronary computed tomography
angiography (CCTA), and autopsy studies. (14). our patient was examined
with CT- coronary angiography, which confirmed the diagnosis.
Currently, there are no universal guidelines for the treatment of MB.
Most experts agree that the first line treatment for individuals
experiencing symptoms of myocardial bridge typically should be
medications like beta-blockers or non-dihydropyridine calcium channel
blockers. It is advisable to steer clear of nitrates as they could
exacerbate symptoms. It is also advised that surgical interventions
should be pursued for patients who don’t respond to medical therapy.
Surgical interventions, such as myotomy, intracoronary stenting and
coronary artery bypass graft surgery have been employed for persistent
symptoms, yet the long-term prognosis remain uncertain. Another
treatment option include stent placement. (15, 16). Our patient was
treated with beta blocker, and calcium channel blockers without
symptomatic response. She was counseled on surgical intervention
options.