Invited commentary

Abstract

Closure of the Patent Ductus arteriosus (PDA) in adult patients frequently presents a significant surgical challenge. The friability of the ductal tissue secondary to the presence of calcification and other atherosclerotic changes in the ductal wall and the frequent association with pulmonary artery hypertension make the conventional division and suture procedure extremely hazardous, if not impossible. In addition the presence of endarteritis and/or aneurysmal dilatation can increase the risk of the operation markedly. Toda and associates report their clinical experience with complex PDA closure in adults using a transpulmonary approach using cardiopulmonary bypass. Temporary occlusion of the ductus is accomplished with a balloon catheter placed through the ductus. Direct closure of patch closure of the pulmonary orifice of the PDA was selected based on the quality of the tissues and the size of the communication. They used this technique in nine patients without deaths or any reported complications. Neither recanalization nor aneurysmal dilatation was recognized during the follow up period which averaged 55 months. This article confirms the findings of others [1Bhati B.S. Nandakumaran C.P. Shatapathy P. John S. Cherian G. Closure of patent ductus arteriosus during open heart surgery.J Thorac Cardiovasc Surg. 1972; 63: 820-826PubMed Google Scholar, 2Taira A. Akita H. Patch closure of the ductus arteriosus an improved method.Ann Thorac Surg. 1976; 21: 454-455Abstract Full Text PDF PubMed Scopus (11) Google Scholar, 3Wernly J.A. Ameriso J.L. Intra-aortic closure of the calcified patent ductus. A new operative technique.J Thorac Cardiovasc Surg. 1980; 80: 206-210PubMed Google Scholar, 4Omari B.O. Shapiro S. Ginzton L. Milliken J.C. Baumgartner F.J. Closure of short, wide patent ductus arteriosus with cardiopulmonary bypass and balloon occlusion.Ann Thorac Surg. 1998; 66: 277-278Abstract Full Text Full Text PDF PubMed Scopus (22) Google Scholar, 5Toda R. Moriyama Y. Taira A. Balloon use for patent ductus arteriosus closure with cardiopulmonary bypass.Ann Thorac Surg. 1999; 67: 1215PubMed Google Scholar], that temporary balloon occlusion of the ductus and patch closure of the ductal orifice are useful techniques which circumvent most of the hazards associated with PDA closure in the adult. However, their excellent surgical results notwithstanding, this work raises two important points for commentary, namely, the use of cardiopulmonary bypass and the long term potential consequences of leaving the ductus connected to the aorta. The procedure described here requires cardiopulmonary bypass and full heparinization with the potential risk and increased cost associated with the use of the heart lung machine. In addition, this technique implies surgical manipulation and suturing of the pulmonary artery which is frequently thin and friable due to pulmonary artery hypertension. More importantly, with the transpulmonary closure the PDA remains exposed to systemic pressure with the potential for thrombosis, infection or aneurysmal dilatation. While the authors reported the absence of any ductal complication in their patients, it is unknown what will be the long term consequences of the surgically created “ductal diverticulum”. Concerns about the potential complications of leaving the ductus connected to the aorta have led the commentator and others to recommend transaortic closure of the PDA. Safe temporary aortic occlusion can reproducibly be achieved with the use of temporary heparin coated aortic shunts without the need for heparinization or cardiopulmonary bypass. Recently, we have exclusively favored the use of active shunts. In these conditions, patch closure of the aortic orifice can safely be performed with continuous suture (most commonly) which can be brought outside for tying. Patient selection is assisted by non-invasive aortic imaging studies which permits the assessment of aortic pathology that could contraindicate this technique. In my opinion transpulmonary closure of the PDA should be reserved to patients undergoing concomitant cardiac procedures or for patients in whom the severity of aortic atherosclerosis make unwise to proceed with transaortic closure.