Aneurysms arising from the pulmonary artery are a rare condition and bear a high risk of death from rupture, dissection or RV failure. We report a case of a pulmonary artery aneurysm secondary to a patent ductus arteriosus, successfully treated with aneurysmectomy and patch repair.
Los aneurismas originados de la arteria pulmonar son una condición rara, con elevada mortalidad asociada a su ruptura, disección, o disfunción ventricular derecha. Se reporta el caso de un aneurisma gigante de la arteria pulmonar en un adulto, secundario a un conducto arterioso persistente, el cual fue tratado satisfactoriamente de forma quirúrgica mediante resección y reparación con parche.
A 26-year-old man presented at our clinic with a three months history of intermittent chest pain with moderate exertion, associated with palpitations. His past medical history included a PDA diagnosed when he was 10 years old, with a previous episode of infectious endarteritis diagnosed and treated with antibiotics for 6 weeks at another institution, after which he lost follow-up. At admission, on physical examination he had a left parasternal thrust on the 2nd intercostal space, and a grade 4/6 continuous murmur in the left infraclavicular area. No signs of a rheumatologic disease were present. His vital signs were normal and a blood pressure of 130/80.
Electrocardiogram was unremarkable. Chest X-ray showed mild cardiomegaly, increased pulmonary blood flow, and considerable mediastinal enlargement. A transthoracic echocardiography showed normal size and function of both ventricles with left ventricle ejection fraction of 70%, normal valves and no pulmonary hypertension (systolic pressure of 40mmHg estimated by tricuspid regurgitation). There was a 15-mm patent ductus arteriosus with a pulmonary end of 3.6mm diameter with continuous left-to-right shunt and a systolic gradient of 50mmHg. A chest computed tomography scan (Figs. 1 and 2) revealed an arterial duct with a small pulmonary end of 3mm and a calcified aneurysmal dilatation of the anterior wall of the pulmonary arterial trunk with a maximal diameter of 64mm, the pulmonary arteries were normal and showed no signs of obstruction.
The patient was taken to the operating room. Through a median sternotomy, cardiopulmonary bypass was initiated through bicaval cannulation on mild hypothermia.
The aneurysm measured 7×6cm and was located 12mm distal to the pulmonary annulus (Fig. 3). The aneurysm wall, highly calcified, and with no vegetations, was resected and the pulmonary artery trunk was reconstructed using a bovine pericardial patch. Then, the ductus was ligated on both ends. The cardiopulmonary bypass was stopped, with a total bypass time of 113min and an aortic cross-clamp time of 60min. Patient was extubated within 24h. He had an uneventful postoperative period. The specimen was subjected to histological examination, and showed a true aneurysm of the pulmonary artery.
He was discharged home on postoperative day 6. Three years after the surgery, he is on NYHA functional class I, with complete resolution of his symptoms and a normal physical exam.
DiscussionCHD have been recognized as the main cause of pulmonary artery aneurysms. In decreasing order, they include PDA, ventricular septal defects, atrial septal defects and less frequently, conotruncal defects have also been associated.1,2 Infectious complications, such as endarteritis, have also been implied as risk factors.2
This implies the importance of the prompt diagnosis of all congenital heart defects as well as the percutaneous or surgical closure.
The aneurysm presented in the case measured 64mm in diameter. Pulmonary artery dilatation has been defined beyond a 29mm width (and up to 31mm in females), and when the dilation exceeds 40mm, an aneurysm should be considered.3
Not enough cases have been reported to develop evidence-based guidelines on the appropriate management of such cases, but interest has been raised in order to prevent lethal complications such as dissection and rupture. Some of the risk factors that have been identified and that may increase the rate of the complications mentioned include the width and the growth rate of the aneurysm, and the presence of pulmonary hypertension, usually associated to a CHD. Absolute values differ according to different case series, but surgery should be considered with a width >5.5cm, a growth rate >2mm/year or a pulmonary pressure >50mmHg.1,4,5
Treatment options include pulmonary artery replacement with a graft or aneurysmectomy and repair with pericardial patch (either autologous or heterologous), such as the case we described. Interventional techniques, such as occlusion of the aneurysm's neck or excluding the aneurysm with an occluded stent, have been described, yet, long-term follow-up to confirm safety and outcomes is pending. We consider that at the time of the present case, surgery should be considered the first treatment option until such concerns are properly addressed.4,5
FundingThe authors received no financial support for the research, authorship, and/or publication of this article.
Authors’ statementPermission was granted by the patient to publish the case report.
Informed consentInformed consent was obtained by the patient and family to underwent surgery and to publish the results and the article.
Conflict of interestThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.