Surgical Experience with Unroofed Coronary Sinus

Surgical Experience with Unroofed Coronary Sinus Jan Quaegebeur, M.D., John W. Kirklin, M.D., Albert D. Pacifico, M.D., and Lionel M. Bargeron, Jr., M.D. ABSTRACT Between January, 1967, and October, 1977, we performed intracardiac repair in 24 patients with unroofed coronary sinus. Eight patients had the so-called pure form of the syndrome, with the concomitant findings of total absence of the partition between the coronary sinus and left atrium, connection of the left superior vena cava (LSVC) to the upper left comer of the left atrium, and a coronary sinus type of atrial septal defect. In 2 additional patients this combination was repaired, along with repair of the common atrium in 1 and tetralogy of Fallot in the other. In 4 patients with either a partial or complete atrioventricular canal defect, only the distal or downstream portion of the sinus was unroofed so that the coronary sinus ostium was considerably to the left of its usual location. In 6 patients, 5 of whom had situs ambiguous, the unroofed coronary sinus was associated with complex congenital heart disease, and in 5 there was a L(contralatera1) SVC. Three of these 6 patients died. The basic repair consists of roofing the coronary sinus from within the left atrium, so that the LSVC drains through the newly created coronary sinus and its ostium into the right atrium. In the absence of a LSVC, the basic repair is simply closure of the coronary sinus atrial septal defect. This leaves the coronary veins draining into the left atrium. In 1965, repair of an unroofed coronary sinus in a patient who also had a left superior vena cava (LSVC) and common atrium was reported 141. Between January, 1967, and October, 1977, we carried out intracardiac repair in 24 patients with unroofed coronary sinus occurring either as an isolated anomaly or in combination with other simple or complex cardiac malformations. A method of surgical identification and man- From the Departments of Surgery and Pediatrics, University of Alabama Medical Center, Birmingham, AL. Presented at the Twenty-seventh International congress of the European Society of Cardiovascular Surgery, July 1, 1978, Lyon, France. Accepted for publication Aug 9, 1978. Address reprint requests to Dr. Kirklin, Department of Surgery, University Station, Birmingham, AL 35294. agement has evolved, the latter based on repair by "roofing" the coronary sinus when a LSVC is associated with the unroofed sinus [41 or by simple closure of the interatrial communication that is present. Material The operative notes on all patients undergoing repair of congenital cardiac defects at the Medical Center of the University of Alabama in Birmingham between January, 1967, and October, 1977, were reviewed. We searched for patients who had a defect in the partition between the coronary sinus and left atrium or absence of the partition (and thus of the coronary sinus itself). Since this partition normally forms the superior border of the sinus, its partial or complete absence is appropriately termed "unroofed coronary sinus."* Twenty-four patients meeting these criteria were identified (Tables 1, 2). Pure Syndrome with LSVC Eight patients had the pure form of unroofed coronary sinus syndrome, i.e., the single basic defect was unroofing of the sinus (Fig 1). All patients had situs solitus of the viscera and atria, and all had three findings that resulted from the unroofing. (1) One was partial anomalous systemic venous return because of a persistent LSVC anomalously connected to the left atrium. This large vein descended anterior to the hilum of the left lung and entered the left upper comer of the left atrium. The orifice of the LSVC was situated between the base of the left atrial appendage anteriorly and the left pulmonary veins posteriorly. The LSVC was large in all patients. An innominate vein, bridging between the right and LSVC was absent in 7 patients and present in 1. (2) No coronary sinus as such was recognizable since the partition or common wall or roof between the left atrium and what should have been the coronary sinus was totally absent. The coronary *Anderson RH: Personal communication, 1978. 418 0003-49751791050418-08$01.25 @ 1978 by Jan Quaegebeur

419 Quaegebeur et al: Unroofed Coronary Sinus Table 1. Surgical Repair of Unroofed Coronary Sinus Performed at the University of Alabama from 1967 to October, 1977 No. of Unroofed No. of Hospital Coronary Sinus Patients Deaths Pure, with LSVC 8 0 With simple cardiac 10 0 malformations With LSVC 5 0 Common atrium 4 0 with PAVC Tetralogy of Fallot 1 0 Without LSVC 5 0 PAVC (partially 3" 0 unroofed) CAVC (partially 1" 0 unroofed) Tetralogy of Fallot 1 0 With complex cardiac 6 3 malformations With LSVC 5 2 Without LSVC 1 1 Total 24 3 "Unroofed coronary sinus left unrepaired. LSVC = left superior vena cava; PAVC = partial atrioventricular canal; CAVC = complete atrioventricular canal. veins presumably drained individually into the atria, and in 3 patients the surgeon commented on seeing the orifices along the usual pathway of the coronary sinus. In 1 patient a small portion of the roof of the coronary sinus near the atrial septum was present, whereas the upstream portion of it was absent up to the left atrial entrance of the LSVC. (3) A coronary sinus type of atrial septa1 defect was present in the posteroinferior area of the atrial septum, in the location normally occupied by the orifice of the coronary sinus. As described by Raghib and colleagues 131, some atrial septal tissue was present between this defect and the annulus of the tricuspid valve (in contrast to ostium primum atrial septal defects), while posteroinferiorly there was no septal tissue, only atrial wall (in contrast to ostium secundum defects). Besides this typical defect, an open foramen ovale (or ostium secundum atrial septal defect) was present in 2 patients. In 4 of the 8 patients the atrial septal defect was very large (4 by 5 cm) and seemed to represent a confluence of a coronary sinus type of atrial septal defect and an ostium secundum defect. Table 2. Surgical Repair of Unroofed Coronary Sinus Associated with Complex Cardiac Malformations from 1967 to October, 1977 Patient No. Age Anomaly WITH LSVC la 2" 13 mo 3" 7 Y' 4a.c 13 mo 5b,c 16 mo Levocardia; AV concordant connection; common atrium with complete AV canal; DORV; PS Dextrocardia; isolated ventricular inversion; TASVC Levocardia; TASVC Levocardia; common atrium with complete AV canal; DORV; PS; TAPVC to RSVC; diminutive LV WITHOUT LSVCd 6' 10 Situs inversus totalis (mirror-image dextrocardia); complete AV canal; DORV; PS apolysplenia. basplenia. =Died. dthis patient had no contralateral, i.e., right, superior vena cava. LSVC = left (or contralateral) superior vena cava; AV = atrioventricular; DORV = double-outlet right ventricle, PS = pulmonary stenosis; TASVC = total anomalous systemic venous connection; TAPVC = total anomalous pulmonary venous connection; RSVC = right superior vena cava; LV = left ventricle.

420 The Annals of Thoracic Surgery Vol 27 No 5 May 1979 Fig 1. (A) Persistent left superior vena cava (LSVC) but an otherwise normal heart. The LSVC drains into the coronary sinus and thence into the right atrium (RA) through the ostium of the coronary sinus. The "roof" of the sinus separates the sinus from the left atrium (LA). (B) "Pure" syndrome with LSVC. The roof of the coronay sinus is absent. As a result, the LSVC empties directly into the upper left corner of the LA and an interatrial communication exists between the LA and RA through the coronary sinus atrial septal defect (ASD). (RV = right ventricle; LV = left ventricle.) Associafed with Simple Cardiac Malformafions In 1 patient with tetralogy of Fallot, unroofed coronary sinus and persistent LSVC existed as an associated malformation. Four patients with a common atrium and partial atrioventricular (AV) canal defect had the same associated malformation (Fig 2). These patients had no atrial septum, of course, whereas the patient with tetralogy of Fallot had a septum with a coronary sinus atrial septal defect. None of these patients had an innominate vein. One had hemi-azygos continuation of the inferior vena cava to the persistent LSVC, while the hepatic veins entered separately into the floor of the common atrium on the right side. Five patients had unroofed coronary sinus without persistent LSVC, associated with simple cardiac malformations (see Table 1). One of them, with tetralogy of Fallot, had a completely unroofed coronary sinus and a coronary sinus atrial septal defect (Fig 3). The other 4 patients, Fig 2. Unroofed coronary sinus and left superior vena cava (LSVC) associated with a common atrium. (Abbreviations same as for Figure 1.) LA 7, Fig 3. Complete unroofed coronary sinus and interatrial communication through a coronary sinus atrial septal defect (ASD). No left superior uena cava is present. (Abbreviations same as for Figure 1.)

421 Quaegebeur et al: Unroofed Coronary Sinus RA '$, \. I A Fig 4. Some types of partially unroofed coronary sinus without a left superior vena cava. (A) A fenestration is present in the midportion of the roof of the coronary sinus. Left-to-right or right-to-left shunting can occur at the atrial level, depending on the atrial pressure relations [Z, 23. (B) The downstream portion of the roof of the sinus is absent. There is an ostium primum atrial septa1 defect as part of the partial atrioventricular canal defect. (8 Unroofed upstream portion of the coronary sinus. An interatrial communication is present through the short downstream portion of the sinus [2, 41. Coronary veins empty directly into the left atrium (LA). (Abbreviations same as for Figure I.) 3 with a partial AV canal defect and 1 with a complete AV canal defect, had only the downstream portion of the coronary sinus unroofed, resulting in drainage of the sinus into the atria considerably more to the left than usual (Fig 4B). Associated with Complex Cardiac Malformations Six patients with unroofed coronary sinus were in this category (see Table 2), 5 of whom had a persistent LSVC. All underwent complete intracardiac repair. Four had polysplenia and 1, asplenia. In the 4 with polysplenia (Patients 1, 2, 3, 4), the infrahepatic inferior vena cava drained into the LSVC through the hemiazygos system. The hepatic veins drained directly into the floor of the atria. One patient (Patient 6) with situs inversus totalis had no contralateral (right) superior vena cava. OperativeProcedures Basic Repair The basic repair is the roofing procedure done for the pure syndrome associated with persistent LSVC (Fig 5). The end result is the creation of a coronary sinus that drains through its ostium into the right atrium, an intact atrial septum except for this ostium, and normal drainage of the LSVC into the right atrium through the coronary sinus. The newly created roof of the coronary sinus starts at the entrance of the LSVC, runs dong the posteroinferior wall of the left atrium anteriar to the left pulmonary veins and behind the mitral valve, and terminates in the right atrium at the ostium of the coronary sinus. The repair is begun at the point of entrance of the LSVC into the left atrium, that is, between

422 The Annals of Thoracic Surgery Vol 27 No 5 May 1979 B \ \ Atrial septum to Fig 5. Repair (or roofing) of an unroofed coronary sinus associated with a persistent left superior vena cava (LSVC). (A) The repair is made by bringing together the posterior left atrial wall over the venous cahula as a stent (not shown). The atrial septum is then repaired so that, together with the tunnel, a coronary sinus ostium is created. (B) The same repair is accomplished in a patient with a common atrium using pericardium. Dacron also may be used. (Abbreviations same as for Figure 1.) the left pulmonary veins posteriorly and the base of the left atrial appendage anteriorly, and must be fashioned carefully so that this entrance orifice is not narrowed and opens completely into the newly created sinus. The roofing process extends inferiorly and toward the atrial septum between the left pulmonary veins posteriorly and the mitral valve anteriorly. The surgeon must always be aware of the possibility of obstructing these by an improper repair, and also of the need to create a large coronary sinus. When the roofing reaches the atrial septum, the anterior, superior, and posterior aspects of the termination of the new sinus are sutured to the atrial septum to separate completely the two atria. Inferiorly, the border is the posterior atrial wall. Except in infants, the venous cannula, which was inserted through the right atrial appendage and advanced into the left atrium and up into the LSVC, was used as a temporary stent. In 4 patients in the pure syndrome group, the left atrial wall was sufficiently redundant that it could be directly sutured together over the stent to create the roof (see Fig 5A). In 2 patients pericardium was used for the roof and was attached by two parallel suture lines to the posteroinferior left atrial wall (see Fig 5B). When only a coronary sinus atrial septal defect is present, an incision into the adjacent fossa ovalis is usually necessary for adequate exposure in the left atrium. When a large confluent atrial septal defect is present, pericardium or Dacron should be used for the roofing. A wide flare should be left at the septal end, which can be used to help close the atrial septal defect. In 2 patients the tunnel was created along the roof of the left atrium instead of in the position usually occupied by the coronary sinus. In 1, the atrial wall was plicated to form the tunnel, and in the other a Dacron tube longitudinally cut in half was used for the roof. In 1 patient with a large bridging innominate vein, the LSVC was ligated, and the coronary sinus atrial septal defect was repaired. These types of basic repairs were used in the 5 patients with the unroofed coronary sinus and persistent LSVC associated with other simple cardiac malformations (1 with tetralogy of Fallot and 4 with a common atrium and partial AV canal defect). Repair When LSVC Not Present In the patient with the unroofed sinus, no LSVC, a coronary sinus atrial septal defect, and tetralogy of Fallot, the absence of the LSVC was not recognized before operation or during the repair of the tetralogy, although the right atrium was opened routinely to determine that the foramen ovale was not patent. In the cardiac surgery intensive care unit, important arterial

423 Quaegebeur et al: Unroofed Coronary Sinus desaturation was observed. An indicator dilution curve obtained from the radial artery after an injection of indocyanine green into the right atrium had a characteristic right-to-left shunt contour, but a curve obtained after injection into the pulmonary trunk did not. Right atrial pressure was higher than left atrial pressure. The diagnosis of right-to-left shunt at the atrial level, probably through a coronary sinus atrial septal defect, was made. At reoperation the next day, the diagnosis was confirmed, and the hole was closed. The right-to-left shunt was absent after this repair. In the 3 patients with an unroofed coronary sinus but no LSVC and the partial AV canal defect, the septal (or downstream) portion of the coronary sinus roof was absent as it was in the patient in whom it was associated with a complete AV canal (see Fig 4B). A classic repair of the AV canal defects was performed, leaving the coronary sinus draining into the left atrium. Repair in Complex Cases In the 6 patients with a complex condition, a complete repair was made in spite of the unusual anatomy. In the 5 in whom the unroofed sinus was associated with LSVC, the repair included the roofing procedure as already described. The roof of the sinus was created with a separate longitudinal half section of Dacron tube in 1 patient and in the others, with a tail of the patch used to form an atrial septum or an intraatrial baffle. In Patient 6, without the associated contralateral superior vena cava (the right superior vena cava since the patient had situs inversus totalis), the unroofed sinus was not repaired. Results No hospital deaths (70% confidence limits, 0-21%) occurred among the 8 patients in whom the pure syndrome was corrected, nor among the 10 (70% confidence limits, 0-17%) in whom it was associated with another ordinary cardiac malformation. No evident arterial desaturation or upper extremity venous stasis had appeared and all were alive and well at the time of writing. Sinus rhythm was present after repair in all 18. Three of the 6 patients in whom the unroofed coronary sinus was associated with complex congenital heart disease died in hospital after the repair. The 3 surviving patients were well when last seen. All patients were in sinus rhythm after repair. Comment Pure Syndrome Raghib and colleagues [31 described the developmental complex we describe as the pure unroofed coronary sinus syndrome with LSVC. Given a heart with LSVC draining normally as it does into the coronary sinus, this complex can be created by excising the entire common wall or partition or roof of the coronary sinus between the sinus and left atrium. Likewise, complete physiological correction is achieved by constructing this roof or partition when it is absent. The importance of repairing the malformation is evident from the reported occurrence of brain abscess and cerebral embolism in these patients [3]. Two of our 8 surgically treated patients had a brain abscess or transient ischemia attacks (Table 3). Such an abscess or embolism and the characteristic arterial desaturation are due to the right-to-left shunting that results from the systemic venous blood of the anomalously connected LSVC draining into the left atrium. The condition is sometimes not diagnosed in its entirety before operation. It should be suspected in every patient with a persistent LSVC and an apparently simple ostium secundum or foramen ovale type of atrial septal defect, although it will be found uncommonly. A history of brain abscess or cyanosis with this morphological combination particularly, alerts the clinician to the possible presence of the pure syndrome of unroofed coronary sinus. We presume from the anatomical relations that the AV node and bundle of His are in the normal location, when only a coronary sinus type of atrial septal defect is present. Using these assumptions, we have not encountered conduction abnormalities after repair in any of our patients. At the present time, the operation is done with cardiopulmonary bypass and cold car-

424 The Annals of Thoracic Surgery Vol 27 No 5 May 1979 Table 3. Data on 8 Patients with "Pure" Syndrome of Unroofed Coronary Sinus with LSVC (2967 to October, 2977) Factor No. of Patients (N = 8) Age 1 to 11 yr 8 History Brain abscess or TIA 2 Mild arterial desaturation s Anatomy LSVC to upper corner LA 8 Innominate vein 1 Coronary sinus type ASD 8 Foramen ovale 2 Confluent with ostium 4 secundum ASD Management Ligation of LSVC, closure 1 of ASD "Roofing" of coronary sinus 7 Using posterior wall LA 4 Pericardium 2 Opened Dacron tube 1 LSVC = left superior vena cava; TIA = transient ischemia attacks; LA = left atrium; ASD = atrial septal defect. dioplegic myocardial preservation. In infants it can be performed with a single venous cannula, profound hypothermia, and total circulatory arrest. Since a stent is helpful in the roofing repair, we prefer whenever possible to cannulate the right superior and inferior vena cava directly or through stab wounds in the adjacent right atrial wall, and then introduce a third tubular venous cannula through the right atrial appendage and advance it across the atrial septal defect into the left atrium and up into the LSVC. Because the right atriotomy is made into the appendage, this venous cannula can slide to the inferior angle of the atriotomy and lie along the posteroinferior atrial wall. This means it is out of the way and in position to serve as a stent over which the roofing may be done. The risk of the operation should be essentially the same as that for repair of an uncomplicated atrial septal defect. It seems a simpler procedure than the alternative of externally reimplanting the left superior vena cava into the right atrium [l, 2, 5, 61. Associated with Simple Cardiac Malformations When the unroofed coronary sinus occurs with LSVC in a malformation such as tetralogy of Fallot, its identification and repair are the same as described for the pure syndrome. When the coronary sinus is completely unroofed, no LSVC is present, and an atrial septum is present, the ostium of the coronary sinus is an atrial septal defect. This was the situation in the patient with tetralogy of Fallot and an unroofed coronary sinus without LSVC. Partially unroofed coronary sinus also occurs. If this involves the most downstream, or rightward, portion of the sinus and if the atrial septum is entirely absent or an ostium primum atrial septal defect is present, the ostium is in the posteroinferior atrial wall and more to the left than usual. We observed this in the 3 patients with a partial AV canal defect and in 1 with a complete AV canal defect, but in none of them was a persistent LSVC present. Associated with Complex Cardiac Malformations Unroofed coronary sinus occurs in this group both with and without a contralateral (left, in situs solitus; right, in situs inversus) superior vena cava. Usually, however, the situs is ambiguous, with polysplenia or asplenia, when the unroofed sinus occurs with complex malformations. The malformation usually includes a common atrium or complete AV canal defect. Recognition at Operation The surgeon must be aware that unroofed coronary sinus with persistent LSVC connected to the left atrium may exist as the pure syndrome or associated with another cardiac malformation whenever a contralateral (left, in persons with situs solitus of the viscera and atriums) superior vena cava is present. When the coronary sinus is completely unroofed and the atrial septum is present, the hole in the septum in the position of the ostium of the coronary sinus can be shown by probing to be simply a hole in the septum and not the ostium of the sinus. In this situation when an ostium primum atrial septal defect is also present or when a large septal defect in the region of the coronary sinus extends to involve the area of the floor of the fossa ovalis, no ostium of the coronary sinus as such

425 Quaegebeur et al: Unroofed Coronary Sinus is present. Several small coronary veins may be seen in the posteroinferior atrial wall along the area usually occupied by the sinus. References de Leva1 MR, Ritter DG, McGoon DC, et al: Anomalous systemic venous connection: surgical considerations. Mayo Clin Proc 50:599, 1975 Mantini E, Grondin CM, Lillehei CW, et al: Congenital anomalies involving the coronary sinus. Circulation 33:317, 1966 Raghib G, Ruttenberg HD, Anderson RC, et al: Termination of left superior vena cava in left atrium, atrial septa1 defect, and absence of coronary sinus: a developmental complex. Circulation 31:906, 1965 Rastelli GC, Ongley PA, Kirklin JW: Surgical correction of common atrium with anomalously connected persistent left superior vena cava: report of a case. Mayo Clin Proc 40:528, 1965 Sherafat M, Friedman S, Waldhausen JA: Persistent left superior vena cava draining into the left atrium with absent right superior vena cava. Ann Thorac Surg 11:160, 1971 Shumacker HB Jr, King H, Waldhausen JA: The persistent left superior vena cava: surgical implications, with special reference to caval drainage into the left atrium. Ann Surg 165:797, 1967 Notice from the American Board of Thoracic Surgery The American Board of Thoracic Surgery now requires that candidates pass both the written and oral portions of the certifying examination. In 1979 only, the two parts of the examination were given together. The time and place was March 22-24, 1979, in Chicago, IL, and the closing date for registration was August 1,1978. In 1980 and thereafter, a written examination will be given prior to the oral examination. It will be necessary to pass the written examination before the oral examination can be taken. The closing date for registration is August 1, 1979. The exact times and places of these examinations will be announced later. Please address all communications to the American Board of Thoracic Surgery, 14640 E Seven Mile Road, Detroit, MI 48205.