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coronary artery aneurysm is defined as coronary dilatation , which exceeds the diameter of normal adjacent segments or the diameter of the patient 's largest coronary vessel by 1.5 times .
aneurysms are observed most commonly in the right coronary artery , and least frequently in the left main coronary artery . among the causes of coronary artery aneurysm , aneurysms following drug eluting stent implantation has also been described .
we present the case of a patient who had infective coronary artery aneurysms that developed after percutaneous intervention ( pci ) , leading to coronary artery to bronchial fistula and manifested as massive hemoptysis .
a 54-year - old male with history of hypertension initially presented with acute onset chest pain . on evaluation
, he was detected to be having critical stenosis in left anterior descending artery ( lad ) and left posterior descending artery ( lpd ) for which drug eluting stenting was done .
however , he had a recurrence of angina after 06 months and on subsequent re - evaluation , in - stent restenosis of the lad was diagnosed .
there was no cough , pleuritic chest pain , loss of appetite and weight loss .
he was febrile ( temp 102f ) , blood pressure was 104/70 mmhg , pulse 90/min , respiratory rate 18 breaths / min .
mantoux test was 5 mm in diameter and there was no afb on sputum examination .
based on radiological appearance pneumonia was diagnosed presumptively , and he was started on intravenous broad - spectrum antibiotics .
fiber optic bronchoscopy revealed mucosal erosion with flap at the entrance of lul bronchus on the medial aspect , with ongoing bleeding from the site .
fibreoptic bronchoscopy revealed bleeding underneath the mucosal flap at the entrance of lul bronchus on medial aspect ( white arrow ) cect chest was done , which showed the coronary stent in the position in the left anterior descending and posterior descending arteries .
a post contrast study displayed extravasation of contrast into this soft - tissue density with identifiable communication with lad [ figure 2a ] .
these findings were indicative of aneurysm arising from lad in the vicinity of the stent .
there was patchy consolidation in lingular segment abutting mycotic aneurysm suggestive of communication between the aneurysm and lung [ figure 2b ] .
( a ) cect ( chest)mediastinal window showing extravasation of contrast into lad aneurysm communicating with lad ( white arrow ) .
( b ) cect ( chest)parenchymal window aneurysm lad with consolidation of adjacent lingular segment ( black arrow ) coronary angiography [ figure 3 ] confirmed the findings of cect chest showing aneurysm involving lad in the vicinity of stent with normal left circumflex and right coronary arteries and extravasation of contrast .
lad aneurysmectomy , extraction of stents and coronary artery bypass grafting ( cabg ) with left internal mammary artery ( lima ) to lad was done .
after surgery , the patient improved symptomatically with cessation of hemoptysis and subsidence of fever .
thereafter , he was continued on medical management in the form of dual antiplatelet agents , antianginal and antihypertensive drugs . coronary angiogram demonstrating aneurysm in left anterior descending artery ( black arrows )
other causes of coronary artery aneurysm include kawasaki disease , percutaneous coronary interventions ( pci ) , inflammatory arterial diseases , systemic lupus erythematosus , syphilis , takayasu disease , chest traumas and connective tissue disorders .
coronary artery aneurysms after pci are sporadic ( 0.3 - 0.6% ) being described in few case reports only .
our patient developed coronary artery aneurysm , as a complication of pci , which is a rare entity .
coronary artery aneurysm in our patient was further complicated by coronary artery to bronchus fistula leading to hemoptysis .
coronary artery aneurysm complicating into the coronary artery fistula in connection with lung has not been reported yet .
previously coronary artery fistula ( post coronary artery aneurysm ) has been described in relation to cardiac chambers only .
residual dissection and deep arterial wall injury ( rupture or resection of the vessel media ) caused by oversized balloons or stents , high - pressure balloon inflations , atherectomy , and laser angioplasty have all been associated with coronary artery aneurysms after coronary intervention .
drug - eluting stents ( des ) , which locally elute antiproliferative drugs , can dramatically inhibit neo intimal growth , thereby suppressing re - stenosis but at the same time potentially causing coronary aneurysms due to other mechanisms , such as delayed re - endothelialization , inflammatory changes of the medial wall , and hypersensitivity reactions .
coronary infection after stenting can present days to weeks after intervention , most frequently as an acute coronary syndrome , in gross contrast to this , our patient presented with hemoptysis , which has not seen in earlier studies .
our patient had a fistulous connection with left bronchus as the complication of the aneurysm which was quite evident on bronchoscopy , computed tomography and intraoperatively .
there was associated consolidation of lingular segments due to trickling down of blood from fistula .
treatment options for coronary aneurysm consist of medical management with the use of antiplatelet and anticoagulation therapy to prevent thrombus formation within the aneurysm .
surgery should be considered for patients with large aneurysms because of the high risk of rupture .
our patient had developed the fistula as a result of the mycotic coronary artery aneurysm for which he underwent lad aneurysmectomy , extraction of stents and cabg with lima to lad .
we report a case of left anterior descending coronary artery to left upper lobe bronchus fistula arising out of the coronary artery aneurysm , secondary to drug eluting balloon angioplasty done for in - stent restenosis in the left anterior descending coronary artery in a 54-year - old male . 
 this is an unreported entity yet .