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Coronary artery anatomy in transposition of the great vessels in relation to anatomic surgical correction
Coronary artery anatomy in transposition of the great vessels in relation to anatomic surgical correction Because of the inadequacies of physiologic correction of transposition of the great arteries (TGA), we have been experimenting with direct anatomic correction of the anomaly. The procedure involves switching the aorta (with the coronary arteries attached) and the pulmonary artery. Studies in preserved infant hearts have indicated the technical feasibility of this operation. Results with the reverse of the procedure, to create a laboratory model of TGA in dogs, have been encouraging as well.
S. C. Balderman, M.D., C. L. Athanasuleas, A.B., and C. E. Anagnostopoulos, M.D., * Chicago, Ill.
The intra-atrial baffle operation for physiologic correction of transposition of the great arteries (TGA), first proposed by Albert' in 1954, has gained popularity since the report of successful clinical application by Mustard- in 1964. Despite a reduction in immediate morbidity and mortality rates, ~ long-term results clearly indicate that such a procedure is less than ideal. Based on our' review of 591 such operations, the rate of significant postoperative complications is high (30 per cent), and by the fifth postoperative year the mortality rate reaches 37 per cent. Although many series report the postoperative mortality rate to be about 10 per cent," several recent studies suggest that the feared long-term complications of venous obstruction," tricuspid insufficiency,' and dysrhythmias" may be prohibitive and that From the Section of Thoracic and Cardiovascular Surgery, University of Chicago, Chicago, Ill. Received for publication June 25, 1973. Address for reprints: C. E. Anagnostopoulos, M.D., Department of Surgery, University of Chicago Hospitals, 950 East 59th Street, Chicago, Ill. 60637. ·Established Investigator, American Heart Association.
208
the intra-atrial baffle procedure may not be the definitive answer to the problem of correction of TGA. We feel that advances in the past 15 years in anesthesia, microsurgery, and cardiopulmonary bypass techniques warrant consideration of direct anatomic correction of TGA, i.e., switching the aorta (with both coronaries still attached) and the pulmonary artery. The reverse of such a procedure has been proposed by one of us (c. E. A. 0 ) in order to create a laboratory model of TGA. The anatomy of the coronary arteries in TGA has been well defined in studies by Shaher'? and Elliot." However, the feasibility of such a procedure depends on these observations together with quantitative assessment of the degree of anatomic mobility of the coronary arteries. Thus the purpose of this study is to evaluate these parameters with respect to this new proposed technique. Method
Fifty-eight formalin-preserved hearts with TGA, harvested before the. subject was 10
Volume 67
Coronary artery anatomy in TGA
Number 2
209
Februory, 1974
~l
8
Fig. 1. Coronary artery in transposition. A, Distance from coronary ostium to first branch. B, Distance from first branch to theoretical new position of the ostium after surgical connection. Distance A minus B is the distance the coronary artery must be moved to occupy its new site. If positive, simple switching is possible since there is excess artery. If negative, the artery needs to be stretched to reach its new site.
weeks of age, were studied. * Both coronary arteries were carefully exposed by blunt dissection, and the distance from the origin of the coronary artery at the aortic root to its first branch was recorded as distance A, for the left coronary and A r for the right (Fig. 1). The first branch is thought to represent an anchoring point beyond which additional mobility of the main vessel, after it is freed by dissection, is restricted. The distance from this branch to a point on the circumference of the pulmonary artery, geometrically analogous to the site of the coronary ostium on the aorta, was measured as distance BI and Br for the left and right coronary arteries, respectively. This point on the pulmonary artery is, therefore, the theoretical new position of the ostium after the aorta is sutured to the transected pulmonary artery or after direct reimplantation of the coronary ostinum. The difference in distance A minus B indicates the distance the coronary artery would have to be stretched, while still attached to the aorta, in order to shift it to its new proposed site on the pulmonary artery. We have chosen the future site of the coronary ostia on the pulmonary artery to be identical to their position on the aorta in order to standardize the measurement of distance B. However, an alternative closer "The hearts were studied at the Hektoen Institute for Medical Research through the courtesy of Dr. Maurice Lev, Chairman.
Table I. Feasibility oj switching in 58 hearts with TGA No. of hearts 11 26 21
Description yy XX XY
Legend: X, Tension on coronary artery :::: 2 mm. after transposition. Y, Tension on coronary artery> 2 mm. after transposition. Coronary arteries labeled X are considered movable by these criteria. Thus 26 of S8 hearts (4S per cent) are candidates for direct switching of the aorta and pulmonary artery to analogous sites.
site for switching the coronary arteries may still be possible, even if primary "analogous" shifting is prohibited. Results
In all hearts the coronary artery pattern was type 1 according to the Shaher-? classification (i.e., right coronary artery arising from the posterior sinus and left coronary artery aising from the left sinus). The measurements of distance A are listed in Fig. 2. In only 15 coronary arteries was the distance from the origin to the first branch less than 4 mm. Of the 116 coronary arteries measured, 44 would need to be stretched more than 2 mm. to reach their proposed new position and 48 could be moved with no tension; in 24 arteries distance A was less than distance B (Fig. 3). The coronary arteries of an infant heart can be dissected and stretched approximately 2 mm. and still remain widely patent
2 10
The Journal of Thoracic ond Cardiovascular
Balderman, Athanasuleas, Anagnostopoulos
Surgery
30 11l LU
ii:
LU
I-
20
...
15
II:: LU
10
II::
4
0
CD
2 ~
z
Left
Right
25
5 0
2
4
6
8
10 12
~14
2
4
6
8
10 12
~14
MM MM Fig. 2. Length (in millimeters) of left and right main coronary arteries before first branch in 58 hearts from infants less than 10 weeks of age who had transposition of the great arteries.
25
11l LU
-
20
+
INDICATES TENSIDN INDICATES SLACK
ii:
LU
I-
II::
4
15
~ II:: LU CD
10
~
~
z
5
• I
-4 -3 -2 -1 0 1 2 3 4 >4 MM DISTANCE THE ARTERY MUST STRETCH TO REACH NEW POSITION DERIVED BY DISTANCE A-B ~4
Fig. 3. Switching of aorta and pulmonary artery is possible if the distance A minus B is -2 mm,
or greater.
(by gaining length from mobilization and conversion of part of the aortic sinuses). In 26 hearts both arteries were movable (45 per cent), i.e., distance A minus B was less than or equal to 2 mm. In 21 hearts (36 per cent) one artery could be moved, and in 11 (19 per cent) hearts both arteries were too short to be moved without considerable extra dissection (Table I). Discussion
Measurements in autopsied hearts are less than ideal. The values obtained for distance B are likely to be in greater error than those
for distance A, perhaps up to 20 per cent, due to the flexibility of the structures. The data are of interest since they offer an idea of distances involved in planning a direct repair of TGA at the level of the great vessels themselves. Direct repair of TGA by switching the aorta (with the coronary arteries attached) and the pulmonary artery is theroretically ideal, since this method avoids the problems of right ventricular failure, tricuspid insufficiency, dysrhythmias, and pulmonary or systemic venous obstruction by the intra-atrial baffle. This operation should be done as soon as the diagnosis is made in order to prevent early changes in the pulmonary vasculature.P Also, if surgery is delayed and a ventricular septal defect is not present, the left ventricle may not be prepared to maintain systemic output. From our data it appears that in 32 hearts (55 per cent) one or both coronary arteries would need to be stretched beyond the hypothetical 2 mm. limit. This apparent limitation can be overcome by several methods." Freeing the coronary artery from the epicardium provides additional mobility for the vessels. If this is inadequate, a subclavian or internal mammary artery can be detached from the root, together with a cuff or aorta, and anastomosed directly to the nontransposable coronary in an end-to-end fashion. Since one or both coronaries may be too short for direct movement in almost half of
Volume 67 Number 2 Februory, 1974
Coronary artery anatomy in TGA
21 1
Fig. 4. Proposed technique in those patients whose anatomy prevents switching to analogous site. Left, Site of incisions on aorta (A) and pulmonary artery (P) are indicated. The aortic incision is carried beneath the coronary ostia but above the valve. Right, Longitudinal portions of incisions are closed and similar incisions are made directly opposite. The pulmonary artery and aorta are now switched. The coronary arteries are moved a minimum distance to the proximal pulmonary artery.
the cases, we have devised an alternative procedure that allows movement of the arteries to the nearest point on the pulmonary artery rather than to a site analogous to their original position on the aortic root. In such an approach the aorta and pulmonary artery are transected by a curved incision which has both transverse and longitudinal components, as indicated in Fig. 4, left. The incision is carried below the coronary ostia, with the valve left intact. The distance from the ostium to the valve cusp is adequate for such an incision." The longitudinal incision on the lateral aspect of the aorta is then closed and a new one is made directly opposite. The new incision tailors the aorta to its new site on the proximal pulmonary artery (Fig. 4, right). In such an approach the coronary arteries are not moved several millimeters. Rather they are respositioned to a point on the proximal pulmonary artery trunk nearest their original location (Fig. S). This approach should enable the surgeon to shift vessels in those cases in which simple switching to an analogous site is impossible because of the anatomic limitation in the length of the arteries. Note also that this procedure eliminates the twisting or rotation of the coronaries inherent in Idriss'> operation.
Fig. S. Completed anatomic repair of transposition of the great arteries. Note that the coronary arteries occupy a medial position on the proximal pulmonary artery as opposed to a lateral one, which would be the case in direct switching if favorable anatomy were present.
In summary, the coronary artery anatomy in TGA is such that direct switching of the vessels to achieve anatomic correction is possible. Preliminary results with the reverse of this operation to create an animal model of transposition are encouraging and have demonstrated the technical feasibility of operating on vessels of this size."
The Journal of
212
Balderman, Athanasuleas, Anagnostopoulos
REFERENCES
2 3
4
5
6
7
8
Albert, H. H.: Surgical Correction of Transposition of the Great Vessels, Surg, Forum 5: 75, 1954. Mustard, W. T.: Successful Two-Stage Correction of Transposition of the Great Vessels, Surgery 55: 469, 1964. Clarkson, P. M., Barratt-Boyes, B. G., Neutze, J. M., and Lowe, G. B.: Results Over a TenYear Period of Palliation Followed by Corrective Surgery for Complete Transposition of the Great Arteries, Circulation 45: 1251, 1972. Balderman, S. C., Athanasuleas, C. L., and Anagnostopoulos, C. E.: A Review of 591 Atrial Baffle Operations, Ann. Thorac. Surg. In press. Breckenridge, I. M., Stark, J., Bonham-Carter, R. E., Oelert, H., Graham, G. R., and Waterston, D. J.: Mustard's Operation for Transposition of the Great Arteries: Review of 200 cases, Lancet 1: 1140, 1972. Stark, J., Tynan, M. J., Ashcraft, K W., Aberdeen, E., and Waterston, D. J.: Obstruction of Pulmonary Veins and Superior Vena Cava After the Mustard Operation for Transposition of the Great Arteries, Circulation 45: 116, 1972 (Supp!. I). Tynan, M., Aberdeen, E., and Stark, J.: Tricuspid Incompetence After the Mustard Operation for Transposition of the Great Arteries, Circulation 45: 111, 1972 (Supp!. I). EI Said, G., Rosenberg, H. S., Mullins, C. E., Hallman, G. L., Cooley, D. A., and Mc-
9
10
11
12
13
14
15
Thoracic and Cardiovascular Surgery
Namara, D. G.: Dysrhythmias After Mustard's Operation for Transposition of the Great Arteries, Am. J. Cardio!. 30: 526, 1972. Anagnostopoulos, C. E., Athanasuleas, C. L., and Arcilla, R. A.: Toward a Rational Operation for Transposition of the Great Arteries, Ann. Thorac. Surg. 16: 458, 1973. Shaher, R. M., and Puddu, G. C.: Coronary Arterial Anatomy in Complete Transposition of the Great Vessels, Am. J. Cardio!. 17: 335,1966. Elliott, L. P., Amplatz, K, and Edwards, J. E.: Coronary Arterial Patterns in Transposition Complexes, Am. J. Cardiol, 17: 362, 1966. Ferencz, C.: Transposition of the Great Vessels: Pathophysiologic Considerations Based Upon a Study of the Lungs, Circulation 33: 232, 1966. Anagnostopoulos, C. E.: A Proposed New Technique for Correction of Transposition of the Great Arteries, Ann. Thorac. Surg. 15: 565, 1973. Idriss, F. S., Goldstein, I. R., Grana, L., French, D., and Potts, W. J.: A New Technique for Complete Correction of Transposition of the Great Vessels: An Experimental Study With a Preliminary Clinical Report, Circulation 24: 5, 1961. Anagnostopoulos, C. E., Athanasuleas, C. L., and Balderman, S. C.: A New Experimental Model of Transposition (Abstr.), Circulation 48: 138, 1973 (Suppl, IV).
S. C. Balderman, M.D., C. L. Athanasuleas, A.B., and C. E. Anagnostopoulos, M.D., * Chicago, Ill.
The intra-atrial baffle operation for physiologic correction of transposition of the great arteries (TGA), first proposed by Albert' in 1954, has gained popularity since the report of successful clinical application by Mustard- in 1964. Despite a reduction in immediate morbidity and mortality rates, ~ long-term results clearly indicate that such a procedure is less than ideal. Based on our' review of 591 such operations, the rate of significant postoperative complications is high (30 per cent), and by the fifth postoperative year the mortality rate reaches 37 per cent. Although many series report the postoperative mortality rate to be about 10 per cent," several recent studies suggest that the feared long-term complications of venous obstruction," tricuspid insufficiency,' and dysrhythmias" may be prohibitive and that From the Section of Thoracic and Cardiovascular Surgery, University of Chicago, Chicago, Ill. Received for publication June 25, 1973. Address for reprints: C. E. Anagnostopoulos, M.D., Department of Surgery, University of Chicago Hospitals, 950 East 59th Street, Chicago, Ill. 60637. ·Established Investigator, American Heart Association.
208
the intra-atrial baffle procedure may not be the definitive answer to the problem of correction of TGA. We feel that advances in the past 15 years in anesthesia, microsurgery, and cardiopulmonary bypass techniques warrant consideration of direct anatomic correction of TGA, i.e., switching the aorta (with both coronaries still attached) and the pulmonary artery. The reverse of such a procedure has been proposed by one of us (c. E. A. 0 ) in order to create a laboratory model of TGA. The anatomy of the coronary arteries in TGA has been well defined in studies by Shaher'? and Elliot." However, the feasibility of such a procedure depends on these observations together with quantitative assessment of the degree of anatomic mobility of the coronary arteries. Thus the purpose of this study is to evaluate these parameters with respect to this new proposed technique. Method
Fifty-eight formalin-preserved hearts with TGA, harvested before the. subject was 10
Volume 67
Coronary artery anatomy in TGA
Number 2
209
Februory, 1974
~l
8
Fig. 1. Coronary artery in transposition. A, Distance from coronary ostium to first branch. B, Distance from first branch to theoretical new position of the ostium after surgical connection. Distance A minus B is the distance the coronary artery must be moved to occupy its new site. If positive, simple switching is possible since there is excess artery. If negative, the artery needs to be stretched to reach its new site.
weeks of age, were studied. * Both coronary arteries were carefully exposed by blunt dissection, and the distance from the origin of the coronary artery at the aortic root to its first branch was recorded as distance A, for the left coronary and A r for the right (Fig. 1). The first branch is thought to represent an anchoring point beyond which additional mobility of the main vessel, after it is freed by dissection, is restricted. The distance from this branch to a point on the circumference of the pulmonary artery, geometrically analogous to the site of the coronary ostium on the aorta, was measured as distance BI and Br for the left and right coronary arteries, respectively. This point on the pulmonary artery is, therefore, the theoretical new position of the ostium after the aorta is sutured to the transected pulmonary artery or after direct reimplantation of the coronary ostinum. The difference in distance A minus B indicates the distance the coronary artery would have to be stretched, while still attached to the aorta, in order to shift it to its new proposed site on the pulmonary artery. We have chosen the future site of the coronary ostia on the pulmonary artery to be identical to their position on the aorta in order to standardize the measurement of distance B. However, an alternative closer "The hearts were studied at the Hektoen Institute for Medical Research through the courtesy of Dr. Maurice Lev, Chairman.
Table I. Feasibility oj switching in 58 hearts with TGA No. of hearts 11 26 21
Description yy XX XY
Legend: X, Tension on coronary artery :::: 2 mm. after transposition. Y, Tension on coronary artery> 2 mm. after transposition. Coronary arteries labeled X are considered movable by these criteria. Thus 26 of S8 hearts (4S per cent) are candidates for direct switching of the aorta and pulmonary artery to analogous sites.
site for switching the coronary arteries may still be possible, even if primary "analogous" shifting is prohibited. Results
In all hearts the coronary artery pattern was type 1 according to the Shaher-? classification (i.e., right coronary artery arising from the posterior sinus and left coronary artery aising from the left sinus). The measurements of distance A are listed in Fig. 2. In only 15 coronary arteries was the distance from the origin to the first branch less than 4 mm. Of the 116 coronary arteries measured, 44 would need to be stretched more than 2 mm. to reach their proposed new position and 48 could be moved with no tension; in 24 arteries distance A was less than distance B (Fig. 3). The coronary arteries of an infant heart can be dissected and stretched approximately 2 mm. and still remain widely patent
2 10
The Journal of Thoracic ond Cardiovascular
Balderman, Athanasuleas, Anagnostopoulos
Surgery
30 11l LU
ii:
LU
I-
20
...
15
II:: LU
10
II::
4
0
CD
2 ~
z
Left
Right
25
5 0
2
4
6
8
10 12
~14
2
4
6
8
10 12
~14
MM MM Fig. 2. Length (in millimeters) of left and right main coronary arteries before first branch in 58 hearts from infants less than 10 weeks of age who had transposition of the great arteries.
25
11l LU
-
20
+
INDICATES TENSIDN INDICATES SLACK
ii:
LU
I-
II::
4
15
~ II:: LU CD
10
~
~
z
5
• I
-4 -3 -2 -1 0 1 2 3 4 >4 MM DISTANCE THE ARTERY MUST STRETCH TO REACH NEW POSITION DERIVED BY DISTANCE A-B ~4
Fig. 3. Switching of aorta and pulmonary artery is possible if the distance A minus B is -2 mm,
or greater.
(by gaining length from mobilization and conversion of part of the aortic sinuses). In 26 hearts both arteries were movable (45 per cent), i.e., distance A minus B was less than or equal to 2 mm. In 21 hearts (36 per cent) one artery could be moved, and in 11 (19 per cent) hearts both arteries were too short to be moved without considerable extra dissection (Table I). Discussion
Measurements in autopsied hearts are less than ideal. The values obtained for distance B are likely to be in greater error than those
for distance A, perhaps up to 20 per cent, due to the flexibility of the structures. The data are of interest since they offer an idea of distances involved in planning a direct repair of TGA at the level of the great vessels themselves. Direct repair of TGA by switching the aorta (with the coronary arteries attached) and the pulmonary artery is theroretically ideal, since this method avoids the problems of right ventricular failure, tricuspid insufficiency, dysrhythmias, and pulmonary or systemic venous obstruction by the intra-atrial baffle. This operation should be done as soon as the diagnosis is made in order to prevent early changes in the pulmonary vasculature.P Also, if surgery is delayed and a ventricular septal defect is not present, the left ventricle may not be prepared to maintain systemic output. From our data it appears that in 32 hearts (55 per cent) one or both coronary arteries would need to be stretched beyond the hypothetical 2 mm. limit. This apparent limitation can be overcome by several methods." Freeing the coronary artery from the epicardium provides additional mobility for the vessels. If this is inadequate, a subclavian or internal mammary artery can be detached from the root, together with a cuff or aorta, and anastomosed directly to the nontransposable coronary in an end-to-end fashion. Since one or both coronaries may be too short for direct movement in almost half of
Volume 67 Number 2 Februory, 1974
Coronary artery anatomy in TGA
21 1
Fig. 4. Proposed technique in those patients whose anatomy prevents switching to analogous site. Left, Site of incisions on aorta (A) and pulmonary artery (P) are indicated. The aortic incision is carried beneath the coronary ostia but above the valve. Right, Longitudinal portions of incisions are closed and similar incisions are made directly opposite. The pulmonary artery and aorta are now switched. The coronary arteries are moved a minimum distance to the proximal pulmonary artery.
the cases, we have devised an alternative procedure that allows movement of the arteries to the nearest point on the pulmonary artery rather than to a site analogous to their original position on the aortic root. In such an approach the aorta and pulmonary artery are transected by a curved incision which has both transverse and longitudinal components, as indicated in Fig. 4, left. The incision is carried below the coronary ostia, with the valve left intact. The distance from the ostium to the valve cusp is adequate for such an incision." The longitudinal incision on the lateral aspect of the aorta is then closed and a new one is made directly opposite. The new incision tailors the aorta to its new site on the proximal pulmonary artery (Fig. 4, right). In such an approach the coronary arteries are not moved several millimeters. Rather they are respositioned to a point on the proximal pulmonary artery trunk nearest their original location (Fig. S). This approach should enable the surgeon to shift vessels in those cases in which simple switching to an analogous site is impossible because of the anatomic limitation in the length of the arteries. Note also that this procedure eliminates the twisting or rotation of the coronaries inherent in Idriss'> operation.
Fig. S. Completed anatomic repair of transposition of the great arteries. Note that the coronary arteries occupy a medial position on the proximal pulmonary artery as opposed to a lateral one, which would be the case in direct switching if favorable anatomy were present.
In summary, the coronary artery anatomy in TGA is such that direct switching of the vessels to achieve anatomic correction is possible. Preliminary results with the reverse of this operation to create an animal model of transposition are encouraging and have demonstrated the technical feasibility of operating on vessels of this size."
The Journal of
212
Balderman, Athanasuleas, Anagnostopoulos
REFERENCES
2 3
4
5
6
7
8
Albert, H. H.: Surgical Correction of Transposition of the Great Vessels, Surg, Forum 5: 75, 1954. Mustard, W. T.: Successful Two-Stage Correction of Transposition of the Great Vessels, Surgery 55: 469, 1964. Clarkson, P. M., Barratt-Boyes, B. G., Neutze, J. M., and Lowe, G. B.: Results Over a TenYear Period of Palliation Followed by Corrective Surgery for Complete Transposition of the Great Arteries, Circulation 45: 1251, 1972. Balderman, S. C., Athanasuleas, C. L., and Anagnostopoulos, C. E.: A Review of 591 Atrial Baffle Operations, Ann. Thorac. Surg. In press. Breckenridge, I. M., Stark, J., Bonham-Carter, R. E., Oelert, H., Graham, G. R., and Waterston, D. J.: Mustard's Operation for Transposition of the Great Arteries: Review of 200 cases, Lancet 1: 1140, 1972. Stark, J., Tynan, M. J., Ashcraft, K W., Aberdeen, E., and Waterston, D. J.: Obstruction of Pulmonary Veins and Superior Vena Cava After the Mustard Operation for Transposition of the Great Arteries, Circulation 45: 116, 1972 (Supp!. I). Tynan, M., Aberdeen, E., and Stark, J.: Tricuspid Incompetence After the Mustard Operation for Transposition of the Great Arteries, Circulation 45: 111, 1972 (Supp!. I). EI Said, G., Rosenberg, H. S., Mullins, C. E., Hallman, G. L., Cooley, D. A., and Mc-
9
10
11
12
13
14
15
Thoracic and Cardiovascular Surgery
Namara, D. G.: Dysrhythmias After Mustard's Operation for Transposition of the Great Arteries, Am. J. Cardio!. 30: 526, 1972. Anagnostopoulos, C. E., Athanasuleas, C. L., and Arcilla, R. A.: Toward a Rational Operation for Transposition of the Great Arteries, Ann. Thorac. Surg. 16: 458, 1973. Shaher, R. M., and Puddu, G. C.: Coronary Arterial Anatomy in Complete Transposition of the Great Vessels, Am. J. Cardio!. 17: 335,1966. Elliott, L. P., Amplatz, K, and Edwards, J. E.: Coronary Arterial Patterns in Transposition Complexes, Am. J. Cardiol, 17: 362, 1966. Ferencz, C.: Transposition of the Great Vessels: Pathophysiologic Considerations Based Upon a Study of the Lungs, Circulation 33: 232, 1966. Anagnostopoulos, C. E.: A Proposed New Technique for Correction of Transposition of the Great Arteries, Ann. Thorac. Surg. 15: 565, 1973. Idriss, F. S., Goldstein, I. R., Grana, L., French, D., and Potts, W. J.: A New Technique for Complete Correction of Transposition of the Great Vessels: An Experimental Study With a Preliminary Clinical Report, Circulation 24: 5, 1961. Anagnostopoulos, C. E., Athanasuleas, C. L., and Balderman, S. C.: A New Experimental Model of Transposition (Abstr.), Circulation 48: 138, 1973 (Suppl, IV).