Ann Thorac Surg 2005;80:1919-1920
© 2005 The Society of Thoracic Surgeons
Case report
Circumflex Coronary Artery From Right Pulmonary Artery in Hypoplastic Left Heart Syndrome
Emmanuel Villa, MD
a
,
c
,
*
,
Gianluca Brancaccio, MD
a
,
Adriano Carotti, MD
a
,
Paola Francalanci, MD
b
,
Roberto M. Di Donato, MD
a
a Department of Cardiac Surgery, Bambino Gesù Children's Hospital, Rome
b Department of Pathology, Bambino Gesù Children's Hospital, Rome
c Division of Cardiac Surgery, University of Milan, Milan, Italy
Accepted for publication June 7, 2004.
* Address correspondence to Dr Villa, Dipartimento Medico-Chirurgico di Cardiologia Pediatrica, Ospedale Pediatrico Bambino Gesù, Piazza S Onofrio, 4, 00165 Rome, Italy (Email: emmanuel.villa{at}voila.fr).
 |
Abstract
|
|---|
We report the case of a newborn with the very rare association of hypoplastic left heart syndrome and aberrant origin of the circumflex coronary artery from the right pulmonary artery. This condition can jeopardize the result of the Norwood palliation.
|
Introduction
|
|---|
Impaired coronary perfusion after Norwood procedure for hypoplastic left heart syndrome (HLHS) is usually secondary to precoronary stenosis for poor neoaortic reconstruction or to diastolic runoff of systemic blood into the pulmonary circulation through a modified Blalock-Taussig shunt. Ventricular-coronary fistulas, generalized hypoplasia of the coronary arteries, and extrinsic compression by prosthetic patch material are other possible causes of myocardial ischemia [1] and so is the anomalous origin of the left coronary artery from the main pulmonary artery (MPA) [2, 3]. This report describes the case of a newborn who died of myocardial ischemia after first stage palliation of HLHS for an overlooked anomalous origin of the circumflex coronary artery from the right pulmonary artery (RPA).
A 2.8 kg female infant, born at 32 weeks of gestation, was admitted to our department with a diagnosis of HLHS. The infant was already on prostaglandin E1. Upon arrival, respiratory distress and metabolic acidosis prompted endotracheal intubation. A repeat two-dimensional echocardiogram revealed mitral and aortic atresia (MA/AA), intact atrial septum, nonrestrictive bulboventricular foramen, double left pulmonary venous drainage into the left atrium and superior vena cava. The caliber of the ascending aorta was 2 mm and two coronary ostia were clearly identified. The pulmonary artery branches appeared diminutive.
The patient underwent a Norwood-Sano procedure on day 2 of life for a persisting low output state. Cardiopulmonary bypass was established by cannulation of the right atrium and innominate trunk (by means of a sutured 3 mm polytetrafluoroethylene [PTFE] graft). During cooling, the pulmonary confluence was detached, patched, and then anastomosed with a 5 mm PTFE conduit. Cardioplegic perfusion was established from a side port of the arterial cannula and then the innominate artery was snared proximally for isolated cerebral perfusion. Arch reconstruction was performed using a curvilinear patch from a pulmonary homograft. During rewarming we commenced the proximal anastomosis of the PTFE shunt onto the right ventricular (RV) infundibulum. Sinus rhythm returned and the anterior RV wall showed normal contractility.
Within 10 minutes of weaning the patient off cardiopulmonary bypass, the arterial pressure dropped, the right atrium enlarged, and atrial rhythm disturbances appeared. Cardiopulmonary bypass was promptly reinstituted. At an intraoperative transesophageal echocardiographic examination the septal and diaphragmatic walls of the RV were akinetic despite massive inotropic support and ventricular unloading. The heart was, in fact, dilated and there was severe tricuspid valve regurgitation. No anomalies were detected in the neoaorta or in the shunt. However, a second cross-clamping period was undertaken in the attempt to improve coronary perfusion at the level of the reconstructed ascending neoaorta. The opening into the native aortic root was widely patent. Suspecting functional stenosis or kinking of the native ascending aorta opening, however, patch augmentation of the native aortic root was performed. After declamping, and after enough circulatory assistance time, the next weaning attempts failed due to reappearance of the previous hemodynamic and echocardiographic situation despite maximal drug support and pacemaker stimulation. The impossibility to interrupt cardiopulmonary bypass and an intractable coagulopathy led to the patients death in the operating room.
Autopsy revealed an aberrant circumflex coronary artery originating from the mid-portion of the RPA: it was inadvertently clipped during dissection and hemostasis maneuvers around pulmonary arteries (Figs 1 and 2).
It occurred when the patient was already on full cardiopulmonary bypass and during cooling: for this reason no hemodynamic or electrocardiographic alterations were recorded. Finally, histology did not reveal necrotic areas.
View larger version (177K):
[in this window]
[in a new window]
|
Fig 1. Postmortem examination. Usual origin of the left coronary artery from the native ascending aorta and aberrant left circumflex (5 mm clips) from the right pulmonary artery. (Cx = left circumflex coronary artery; LAD = left anterior descending coronary artery; NAA = native ascending aorta; RPA = right pulmonary artery; RV-PA conduit = right ventricle-pulmonary artery conduit.)
|
|
|
Comment
|
|---|
Coronary abnormalities have been reported in patients with HLHS, especially in patients with mitral hypoplasia and aortic atresia (MH/AA). Ventriculoarterial connections are more prominent in this subgroup. Baffa and colleagues [4] studied coronary and right ventricular histologic alterations in different combinations of left-sided hypoplasia-atresia. Apart from several cases of tortuous epicardial arteries, gross anomalies in coronary anatomy were found in 3 of 151 specimens and consisted of a single artery pattern. All these alterations were more frequently associated with the MH/AA variant. Other forms of HLHS have been rarely reported in association with anomalous origin of coronary arteries [2, 3, 5]. To our knowledge, this is the second reported case of isolated circumflex coronary artery directly branching from the RPA. Sarris and colleagues [5] reported an exceptional survival of an infant with HLHS and left coronary artery originating from the RPA, discovered by angiography at 9 months of age before late surgical management. The neonatal case of MA/AA described by Malec and colleagues [2] was an intraoperative finding of left coronary artery from RPA: reimplantation was performed, but in-hospital death occurred. Another case (subtype not specified) was reported in the autoptic study of Bartram and colleagues [1], where inadvertent ligature of an aberrant left circumflex coronary artery from the RPA was identified as cause of intraoperative death. As in our case, the RV was involved by the infarct. Fatal RV failure can occur in the context of left dominance, therefore the ischemic zone can be very wide and septal dyscoordination can produce massive tricuspid regurgitation.
The combination of abnormal origin of coronary arteries and HLHS is a challenge for preoperative diagnosis and intraoperative management. Actually, before operation, the largely patent duct allows similar perfusion in both coronary arteries and consequently ischemic alterations are not detectable. For the same reason, at echocardiography, Doppler reveals anterograde flow in the normal and in the anomalous coronary branches. After detection, surgery can be considered by means of complete cardiac protection with selective cardioplegic perfusion through the RPA and direct aortic reimplantation can be planned. This report once more draws attention to the importance of a detailed evaluation of the coronary anatomy before Norwood palliation to facilitate surgical strategy and to offer better cardiac preservation.
|
References
|
|---|
- Bartram U, Grünenfelder J, van Praagh R. Causes of death after the modified Norwood procedurea study of 122 postmortem cases. Ann Thorac Surg 1997;64:1795-1802.[Abstract/Free Full Text]
- Malec E, Mroczek T, Pajak J, Zaiac A, Kolcz J, Januszewska K. Hypoplastic left heart syndrome with an anomalous origin of the left coronary artery Ann Thorac Surg 2001;72:2129-2130.[Abstract/Free Full Text]
- De Rose Jr JJ, Corda R, Dische R, Eleazar J, Mosca RS. Isolated left ventricular ischemia after the Norwood procedure Ann Thorac Surg 2002;73:657-659.[Abstract/Free Full Text]
- Baffa JM, Chen SL, Guttemberg ME, Norwood WI, Weinberg PM. Coronary artery abnormalities and right ventricular histology in hypoplastic left heart syndrome J Am Coll Cardiol 1992;20:350-358.[Abstract]
- Sarris GE, Drummond-Webb JJ, Ebeid MR, Latson LA, Mee RBB. Anomalous origin of left coronary from right pulmonary artery in hypoplastic left heart syndrome Ann Thorac Surg 1997;64:836-838.[Abstract/Free Full Text]
Top
Abstract
Introduction
