VOL. 121, No. 3 ANGIOGRAPHIC DEMONSTRATION OF THE ABSENCE OF AN ATRIAL SEPTAL DEFECT IN THE PRESENCE OF PARTIAL ANOMALOUS PULMONARY VENOUS CONNECTION* By THOMAS A. SOS, M.D.,t DANIEL TAY, M.D.,t AARON R. LEVIN, M.D., M.R.C.P.,1 DAVID C. LEVIN, M.D.,t and HAROLD A. BALTAXE, M.D.t S HUNTS of oxygenated blood to the systemic venous circulation (left-to_right shunts) due to partial anomalous pulmonary venous connection (PAPVC) cornprise 0.5 per cent of all cases of congenital heart disease5 and are diagnosed and surgically corrected with increasing frequency. In 1964, Schumacker and Judd6 sumrnarized their own experience and those of others in patients with PAPVC where the state of the atnia! septum was known. They found an associated atrial septal defect (ASD) in 90 per cent of patients with PAPVC to the superior vena cava or right atrium whereas in PAPVC to the inferior vena cava, a much rarer site of drainage, only I 5 per cent of patients had an ASD. In cases of total anomalous pulmonary venous connection, an ASD along with a frequently present patent ductus arteriosus is an important avenue of mixing of oxygenated and deoxygenated blood and keeps the patient alive. In most cases of PAPVC, however, an associated ASD serves only to complicate the diagnostician s task. Surgical correction of PAPVC, ASD, or their combined presence is now possible, although the technical approach for each is somewhat different.5 The preoperative determination whether one, the other, or both are responsible for the overcirculated lung fields is therefore of more than academic interest. Clinical, electrocardiographic, plain film chest roentgenographic examination as well as indicator dilution and oxygen saturation data, and even conventional pulmonary NEW YORK, NEW YORK angiography do not reliably establish whether an ASD is present in addition to PAPVC in such patients. The presence of PAPVC with or without an associated ASD, however, can be established roentgenographically by main pulmonary arteniography followed by selective right, or left pulmonary arteniography. MATERIAL, METHOD AND RESULTS In the past 5 years at the New York Hospital 22 patients with clinically suspected left-to-right shunts and subsequently demonstrated by cardiac catheterization were included in this study. When an anomalous pulmonary vein (APV) connecting either to the right atrium or one of its systemic venous tributaries was identifled by main pulmonary arteriography, selective right, or left pulmonary arteriograms were obtained to rule in or out an associated ASD. The above technique demonstrated in 8 patients with PAPVC an intact atnial septum-confirmed at surgery in 5 cases. In all 8 of the above patients with an intact atnial septum, the connection of the APV was supradiaphragmatic. Only 3 out of 22 patients had infradiaphragmatic PAPVC and in none of these was the atnial septum intact (Table ). DISCUSSION Oxygenated blood normally drains via the pulmonary veins into the left atrium. Anomalous pulmonary veins connect directly to the right atrium or indirectly via * From the Division of Cardiovascular Radiology,t and the Division of Pediatric Cardiology4 The New York Hospital-Cornell University Medical Center, New York, New York. Partially supported by a grant from the National Institute of Health No. i TO i HL05966-oI CAR. 591
592 Sos et al. JULY, 1974 TABLE I INCIDENCE OF ASD ASSOCIATED WITH VARIOUS TYPES OF PAPVC SVC Supradiaphragmatic Connection Infradiaphragmatic Connection Left SVC Left Innominate Vein ASD Present 6* 0 I 4 2 1* ASD Not Present 6 I 0 2 0 0 Right Atrium IYC Hepatic * This patient had both right upper lobe APVC to the SYC, and right middle and lower lobe APVC to a hepatic vein. ASD = atrial septal defect; PAPVC = partial anomalous pulmonary venous connection; SVC = superior vena cava; IVC = inferior vena cava; APVC = anomalous pulmonary venous connection. the systemic venous circulation (superior vena cava, left superior vena cava, inferior vena cava, innominate vein, portal vein, hepatic veins or the coronary sinus), resulting in an extracardiac left-to-right shunt. A short summary of the techniques used to diagnose PAPVC follows: although each is useful, they cannot accurately differentiate the presence of PAPVC vs. an ASD or their frequent coexistence. This is because of the physiologic and hemodynamic similarities present in both conditions. A. PHYSICAL FINDINGS AND SYMPTOMS Most patients are asymptomatic. The symptomatic may show shortness of breath, upper respiratory tract infections, cyanosis on exertion, retarded physical development and, rarely, congestive heart failure. P hysical examination reveals a systolic ejection pulmonic murmur due to increased blood flow. Patients with an intact atnial septum have normal, or wide fixed splitting of the second heart sound. Those with an associated ASD have wide splitting of the second heart sound with accentuation of its pulmonic component.4 5 Thus, symptoms and physical findings offer little differential clue. B. ELECTROCARDIOGRAPHY Vein All of the findings are due to left-to_right shunting effectively at the atnial level; thus, not surprisingly, the electrocardiographic abnormalities of PAPVC and ASD are identical. They are most frequently right axis deviation, incomplete right bundle branch block, right ventricular hypertrophy and, rarely, atnial fibrillation.4 5 C. ROENTGENOLOGIC DIAGNOSIS Increased and prominent pulmonary vasculanity and right heart enlargement are the cardinal features of both PAPVC and ASD. In cases associated with sinus yenosus ASDs the right APV may drain into and dilate the inferior ampullary portion of the superior vena cava, which produces a rounded density.3 Even if an APV such as in the Scimitar syndrome were demonstrated, the presence or absence of an associated ASD could not be ruled out. D. CARDIAC CATHETERIZATION AND ANGIOCARDIOGRAPHY I. Catheterization and selective injection of the iipv. If the catheter enters a pulmonary vein from the right atrium, an APV is demonstrated. Unfortunately, it is often difficult to be sure that this pulmonary vein is entered directly from the right atrium or whether it is entered from the left atrium through an ASD.7 2. Oxygen saturation. Oxygen saturation in the right atrium in excess of that in the high superior vena cava or inferior vena cava suggests the presence of a left-tonight shunt.7 It does not, however, separate
VOL. 121, No. 3 Partial Anomalous Pulmonary Venous Connection 593 PAPVC associated with an ASD from PAPVC without an ASD, if the anomalous vein enters directly into the right atrium or into the superior vena cava, inferior vena cava on a systemic vein very close to the night atrium. In these instances an oxygen saturation step-up at the night atnial level in addition to a step-up in the superior vena cava would still not prove the associated presence of an ASD because inferior vena cava blood usually has a higher oxygen saturation than superior vena cava blood due to higher oxygen extraction of the upper part of the body (especially cerebral circulation), as compared to that in the lower pant of the body (renal circulation). 3. Indicator dilution methods. The appeanance time and concentration of green dye* injected into the pulmonary circulation can be measured in the systemic anterial circulation. Left-to-right shunts are demonstrated by extended appearance and decreased concentration of the indicator, but the exact location of the shunt is not identified. Selective left and night pulmonary artery dye injections will give differential dye curves, if one side has an APV in the absence of an ASD,7 similar to selective left and right pulmonary angiography.. Gas inhalation. The early appearance in the right atrium of inhaled gas will demonstrate a left-to-right shunt without identifying its location. 5. zlngiocardiography. Injection of contrast medium into the right ventricle on pulmonary artery will first opacify the pulmonary arteries and later during the socalled levo phase the pulmonary veins which normally drain into and opacify the left atrium, then the left ventricle. At the time of opacification of the left atrium, no contrast medium should be seen in the night atrium. If contrast medium is detected in the left atrium and right atrium almost simultaneously, a left-to-night shunt must be present proximal to the left ventricle. This may be due to an APV, to an * Cardio-Green, Hynson, Wescott and Dunning, Inc. ASD, or a combination of both. If the APV enters the right atrium directly, on systemic vein near the night atrium, th exclusion of an ASD is impossible by this technique. There is, however, an angiocardiographic method to identify, or rule out an ASD iii the presence of PAPVC. Assuming tha t unilateral anom alous pulmon any venous connection (APVC) is demonstrated, or suspected on a main pulmonary arteniognafli (Fig. I, ii and B), it should be followed br selective pulmonary angiography. If necesary, injection of the pulmonary artery ipsilatenal to the APV will more clearly demonstrate the APV (Fig. 3, A and B). Selective injection of the pulmonary artery contnalateral to the APV will opacify the normally draining pulmonary veins which opacify the left atrium during the venous ( levo ) phase. If at this time contrast medium is detected almost simultaneously in the night atrium, the presence of an ASD has been shown. On the other hand, if this injection does not opacify the right atniurri, an ASD has been excluded (Fig. 2), and opacification of the right atrium following the main pulmonary artery injection was due to blood being shunted via the APV. There are a few limitations and pitfalls to the above technique: (a) If only a very small ASD is present, the amount of opacified blood shunted across it may not be detectable in the night atrium., (b) Small sinus venosus ASDs may be easily missed, on are detected in an unusual manner as indicated below. These ASts are located in the high posterior portion of the atnial septum near the entrance of the superior vena cava, and are in 86 pen ce1lt of cases accompanied by night PAPVC2 which drains into the right atrium or into the often dilated ampullary portion of the superior vena cava in close proximity to tje ASD. Thus, theoretically the normal left pulmonary veins may not contribute sinificant amounts of blood to the shunt and therefore the ASD could be missed. Several of our patients, however, with
594 Sos et al. JULY, 5974 FIG. I. Patient with right partial anomalous pulmonary venous connection and an intact atrial septum. Main pulmonary arteriograms, venous ( levo ) phase. (A) The normal left pulmonary veins (black arrows) connect to and opacify the left atrium (LA). l he anomalous pulmonary veins on the right (white arrows) connect to the right atrium (RA). (B) Slightly later both atria (RA and LA) are opacified. night PAPVC had small sinus venosus ASDs which were cleanly demonstrated by a selective left pulmonary artery injection. In each of these cases, the ASD was demonstrated by neflux of contrast material into the superior vena cava through the ASD during atnial systole without appreciable FIG. 2. Same patient as in Figure I. Selective left pulmonary arteriogram. Venous ( levo ) phase. The left pulmonary veins normally opacify the left atrium (LA); however, no contrast material is seen in the area of the right atrium (RA). This demonstrates the absence of an atrial septal defect. opacification of the right atrium (Fig., A and B). This is easily explained by the anatomic location of the sinus venosus ASD in close proximity to the superior vena cava and by the small size of the shunt. The lower portion of the night atrium is filled by unopacified blood from the inferior vena cava and thus reduces the concentration of contrast in the main body of the right atrium to below visible levels. (c) The angiographen must scrupulously observe good technique during selective pulmonary artery injections. Unless the catheter has been advanced well beyond the bifurcation of the main pulmonary artery, the catheter may recoil upon injection or contrast medium may reflux into the opposite pulmonary artery which results in spurious opacification of the night atrium. Selective night, or left pulmonary angiography requires little additional time and manipulation and can be accomplished by using moderate amounts of additional contrast medium without compromising the patient s safety. It yields graphic and reliable demonstration of the nature of the anomalies, which were not available using nonselective methods.
VOL. 121, No. 3 Partial Anomalous Pulmonary Venous Connection 595 #{149}1 -:. I FiG. 3. Patient with right partial anomalous pulmonary venous connection and an associated small sinus venosus ASD. Selective right pulmonary arteriograms. (A) Arterial phase. (B) The venous ( levo ) phase demonstrates the anomalous right pulmonary veins connecting to and opacifying first the dilated ampulla of the superior vena cava (black arrowheads) and then the right atrium (RA). SUMMARY Twenty-two patients with partial anomalous pulmonary venous connection (PAPVC) were studied. In 8 patients, the absence of an associated atnial septal defect was established b a noentgenognaphic method not previously described. (A) Arterial phase. Note the rounded shadow of the dilated ampullary portion of the superior vena cava (black arrowheads) which is visible on chest roentgenograms. (B) Venous ( levo ) phase. The left atrium (LA) is opacified by the normally connecting left pulmonary veins. Note the dense opacification of the dilated ampulla of the superior vena cava (black arrowheads). I his is the only indication of the presence of a small sinus venosus ASD in the absence of contrast medium in the right atrium (RA).... If an anomalous pulmonary vein (APV) is identified or suspected by main pulmonary arteniography, selective injection of
596 Sos et al. JULY, 5974 the ipsilatenal pulmonary artery will more clearly demonstrate it, while selective injection of the pulmonary artery contralateral to the APV will establish whether or not an associated ASD is present. Thomas A. Sos, M.D. Division of Cardiovascular Radiology The New York Hospital-Cornell University Medical Center 525 East 68th Street New York, New York 10021 REFERENCES. BRAUNWALD, E., LOMBARDO, C. R., and MORROW, A. G. Drainage pathways of pulmonary veins in atrial septal defect. Brit. Heart 7., 1960, 22, 385-390. 2. DARIA, J. E., CHEITLIN, M. D., and BEDYNEK, J. L. Sinus venosus atrial septal defect: analysis of fifty cases. Am. Heart 7., 1973, 85, 177-185. 3. DOW, J. D. Radiologic diagnosis of sinus venosus type of atrial septal defect. Guy s Hosp. Rep., 1959, 108, 305-313. 4. HICKIE, J. B., GIMLETTE, T. M. D., and BACON, A. P. C. Anomalous pulmonary venous drainage. Brit. Heart 7., 1956, i8, 365-377.. KALKE, B. R., CARLSON, R. G., FERLIC, R. M., SELLERS, R. D., and LILLEHEI, C. W. Partial anomalous pulmonary venous connections. Am. 7. Cardiol., 1967, 20, 91-101. 6. SCHUMACKER, H. B., and JUDD, D. Partial anomalous pulmonary venous return with reference to drainage into inferior vena cava and to intact atrial septum. 7. Cardiovasc. Surg., 1964, 5, 271-278. 7. SWAN, H. J. C., BURCHELL, H. B., and WOOD, E. H. Differential diagnosis at cardiac catheterization of anomalous pulmonary venous drainage related to atrial septal defects or abnormal venous connections. Proc. Staff Meet. Mayo Clin., 1953, 28, 452-462.
This article has been cited by: 1. J. Peter Harris, Navin Nanda, Scott Stewart, Chloe G. Alexson, James A. Manning. 1983. Echocardiographic definition of right pulmonary venous connection at catheterization. Catheterization and Cardiovascular Diagnosis 9:5, 519-525. [CrossRef] 2. Thomas A. Ports, Kevin Turley, Bruce H. Brundage, Paul A. Ebert. 1979. Operative Correction of Total Left Anomalous Pulmonary Venous Return. The Annals of Thoracic Surgery 27:3, 246-249. [CrossRef]