Discussion
Bacterial infection of the pericardial space is an uncommon cause of
pericardial effusion1. Infected coronary artery
aneurysms are rare and they occur mostly after stent placement or in
septic and immune-compromised patients. However, spontaneous ICAAs have
been reported previously3, as in our case. The
literature of ICAA is mainly based on case reports or case
series4,5. The clinical course of coronary artery
aneurysm remains largely unpredictable and without appropriate diagnosis
and treatment the outcome is invariably poor with sepsis and aneurysmal
rupture with resultant hemodynamic collapse and
death4. Exceedingly high morbidity and mortality have
been reported (mortality 43-53%)5. Surgical
management was the treatment of choice for the most ICAAs. The most
common surgical method is ICAA resection and distal bypass of the artery
(mortality rate of 20.9%)5.
Our case is also uncommon in that the presentation involved purulent
pericarditis. It is unknown whether the aneurysm or purulent
pericarditis preceded. The impaired systolic function of the right
ventricle can be attributed to the myocardial ischemia of the right
ventricle due to the RCA aneurysm. Consequently, we can not determine if
the ICAA was the cause of purulent pericarditis (ICAA leak into the
pericardial sac) or the result of the purulent pericarditis (local
injury of the CAA due to the artery’s wall inflammation and artery’s
wall bacterial infection from pericardial fluid) . Therefore,
safe conclusions about the onset of purulent pericarditis and the
formation of the CAA can not be drawn.
In conclusion, this was a rare case of a spontaneous giant “mycotic”
aneurysm of the RCA presented with purulent pericarditis. ICAAs present
high mortality and surgical management is the treatment of choice in
most cases. When purulent pericarditis and ICAA co-exist the riddle of
the chicken and the egg becomes apparent.