(Figures 2c & 2d).
The present case demonstrates a rare combination of mycotic pulmonary
artery aneurysm (MPAA) in the setting of congenital heart disease (CHD)
and IE. In a congenitally malformed heart, due to turbulence and sheer
force in the blood, the endocardium gets disrupted resulting in seeding
of pathogenic organisms in scarred endocardium, predisposing to
development of vegetations and IE. MPAA are formed in such conditions as
a result of the direct extension of intraluminal septic thrombo-embolus
into the vessel wall. The most common CHD associated with MPAA are
PDA,VSD and corrected Tetralogy of Fallot (TOF), in addition to
intravenous drug abuse and connective tissue disorders. [1,2]‘ The
most important differential diagnosis for MPAA occurring in the
background of CHD and IE is Rasmussen’s aneurysm. The latter is located
in relation to tuberculous cavity and usually distributed beyond the
branches of the main pulmonary arteries in contrary to aneurysm in CHD
where it is located more proximally involving lobar branches. The
management of these patients is difficult due to a lack of clear
guidelines and sparse clinical experience. The prognosis for mycotic
aneurysms of the pulmonary arteries without intervention is horrid with
mortality rates ranging from 40–82% due to rupture. Prompt diagnosis
and timely management is essential to prevent rupture and catastrophic
haemorrhage in these patients. This case highlights the role of CTA in
the evaluation of patients with IE and suspected MPAA as it outpaces TTE
not only in terms of characterization of the aneurysm but also in
demonstrating the extent of thrombo-embolic complications in distal
pulmonary arteries and lung parenchyma.