Idiopathic Pulmonary Artery Aneurysm

Case Report

A 71-year-old man presented to our institution complaining of recent episodes of midsternal chest pain and discomfort. His medical history included gastroesophageal reflux disease and hyperlipidemia. He reported no history of tobacco-smoking.

His physical examination was unremarkable. He was in sinus rhythm, afebrile, and normotensive. However, heart auscultation revealed a grade 2/6 systolic murmur audible over the left sternal border.

An electrocardiogram obtained showed sinus rhythm. A chest roentgenogram showed normal lung fields and a normal heart but was highly suggestive of an enlarged pulmonary artery ([Fig. 1]). A follow-up computed tomography (CT) scan revealed a large main pulmonary artery (MPA) aneurysm, with a diameter of seven centimeters and minor extension into the left pulmonary artery ([Fig. 2]). Transesophageal echocardiography confirmed a markedly dilated MPA. The pulmonic valve appeared to open well with a peak pressure gradient of 10 mmHg. However, there was evidence of mild valvular regurgitation. The right and left ventricular functions were normal with no evidence of a patent ductus arteriosus or septal defects. A coronary angiography was performed with normal results, and the patient was referred for surgery.

Fig. 1 Chest radiograph, posteroanterior view showing an enlarged pulmonary artery.

Fig. 2 Contrast-enhanced computed tomographic scan of the chest showing a large main pulmonary artery aneurysm.

The operation was performed through a median sternotomy. After pericardiotomy, the large MPA aneurysm was assessed; it extended into the left pulmonary artery. Standard cardiopulmonary bypass was established with cannulation of the ascending aorta and the right atrial appendage. The heart was kept beating at normothermia. The MPA was then opened and the arteriotomy was extended to the left pulmonary artery. The pulmonary valve annulus was examined from within the aneurysm and appeared to be normal. The left pulmonary artery aneurysm was noticed to extend down to the branches. An aneurysmorrhaphy of the left pulmonary artery aneurysm was then performed using running 4-0 Prolene sutures. The MPA was excised and replaced with a pulmonary homograft. The distal end of the homograft was anastomosed to the bifurcation of the pulmonary arteries. The proximal end was anastomosed to the remaining rim of the MPA using running 4-0 Prolene sutures. At completion, a transesophageal echocardiogram was performed. The homograft appeared to be in a good position with no evidence of stenosis at the reconstructed sites. The pulmonary valve was intact with no evidence of regurgitation. The patient recovered well in the postoperative period and he continues to be well up to the present time.

References

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