Discussion:
According to angiographic and autopsy data, various causes of coronary
artery embolism have been reported in the literature [10]. Different
studies reported various causes as the most common cause of coronary
artery embolism. A study conducted by Charles et al. reported bacterial
endocarditis as the common cause of coronary embolism, while Prizel et
al. reported valvular heart diseases and cardiomyopathy as the common
risk factors for causing coronary embolism [11, 12]. However, a
recent study conducted by Popovic et al. reported atrial fibrillation as
the most common cause of coronary artery embolism, followed by dilated
cardiomyopathy and bacterial endocarditis respectively [13].
Similarly, Shibata et al. conducted a study on new-onset MI between 2001
to 2013 and reported that 2.9% of AMIs were due to coronary embolism,
with the most prevalent cause reported was atrial fibrillation, followed
by cardiomyopathy and valvular heart disease [10]. Very rarely,
paradoxical embolism causing acute myocardial infarction has been
reported in the literature [14].
Atrial fibrillation patients are at increased risk of left atrium
thrombus formation, particularly in the left atrial appendage, through
Virchow’s triad of blood stasis, endothelial damage, and hypercoagulable
state. These patients benefit from anticoagulation and require life-long
anticoagulation to prevent thrombus formation and associated
complications. In our case, a patient was admitted with a chronic
medical history of atrial fibrillation on anticoagulation with
questionable compliance and was admitted with sepsis and takotasubo
cardiomyopathy, and later complicated by AMI secondary to coronary
embolism to the LAD. Multiple factors played their role in developing
coronary embolism in our patients, with the most common being atrial
fibrillation with questionable compliance with anticoagulation, followed
by takotsubo cardiomyopathy. Coronary artery embolism secondary to
takotsubo cardiomyopathy has been reported in the literature [15],
and the typical apical ballooning form of takotsubo cardiomyopathy seems
to be more vulnerable to thrombus formation, which then leads to various
thromboembolic complications [16].