early embryonic truncus and arches.’ Additional cono- truncal anomalies in patients with tctralogy of Fallot and 22qll dclction are presumed to be the result of neural crest abnormalities.

In summary, all patients with tetralogy and 22qll deletion had 1 to 4 additional conotruncal anomalies, such as high aortic arch, right aortic arch, infundibu- lar septal defect, aberrant origin of the subclavian artery, ma.jor aortopulmonary collateral arteries, and anomalous ductus arteriosus causing isolation of either the left pulmonary artery or the subclavian artery.

Acknowledgment: WC appreciate the editorial help of Leonard M. Linde, MD, and Barbara Levene.

1. Take A, Ando M, Cho K, Kinouchi A. Murakaml Y. tiriologic cafcgori7ation of con~mon congemral hurl discatc. In Van Praagh K. ‘fakao A, eds. Etiology and

Morpho:enesis of Congenital Hwfl Diseax Sew York: Fufura. 19X0:253-26Y. 2. Shprinlrcn RJ, Goldberg RI3, Ixwin ML, Sldorl U, Hcrkman \lD. hrgamnso RV. Young D. A new syndrome InwIving cleft palare. cardiac anomalies, typical facics. and learnin: disabilities velo-car&o-facial syndrome. (‘/q/r ~&~fc Crwrio- far J 197855662. 3. Van Miemp LHS. Kursche JM. Cardwvaxxlar anomalies m DiGcorge syndrome and importance 01 neural crest as a powhle pathogenctic factor. &I .I Cnrdinl 1386; %:I 13x-1137. 4. Dnscoll DA. Salvin J. Scllinper 13. I3udarf ML. \,IcDonald-M&inn DM. Zack- ai HI, Emanwl BS. Prevalence of 2291 I microdcle~iow in DiGeqx and vclo- cardiofacial syndrome: m~phcationc forgenerrc and prenardl dia:no\ic. J .MrdGmrt 1993:30:X13-817. 5. I3um J. Takao A. Wilson D, Cross I, Momma K. Wadlq R. Scamblcr P, Gwxl- bhip J. Conotmncal anomaly face syndrome is acsociatcd with a deletion within chromosome 22q Ii. J Med Gcncr 1993;3O:X22 X24. 6. Wilson DI, Rum J. Scamhler I’. Gwdship I. DiGcorgc syndrome: pan of CATCH 22. J Mrd Gener 1993:30:X52 856. 7. hlawoka R.‘l’akao .A. Kimura 11, Imamura S. Kondo C. Jo0 K, lkeda K. t&hi- hatakc M, .Ando M. Momma K. Confimlation that the cono~runcal anomaly face \yndmme is aaaocidlt!d with a dclcrion within 22qI 1.2. .4u1 J Med Chef 199453: 2X5-289. 8. Freedom IN, Culham JAG. .Llccs CAF. Anelc~anlii,gral~hy of Congenilal I-lean Disease. New York: ?vlMacmillan. 19X4:173-213. 4X7-513. 9. Kirhy ML. Waldo KL. Kales of neural cresr in conpeniral hear! dixax. Cirw la~im 1990;82:332-340.

Coronary Angioplasty for Coronary Stenosis After the Arterial Switch Procedure

Gerd Hausdorf, MD, Christoph Kampmann, MD, and Martin Schneider, MD

T he arterial switch operation is the treatment of choice for the anatomic correction of infants with complete

d-transposition of the great arteries. Transplantation of the coronary arteries from the anterior to the posterior artery is the most challenging surgical part of this pro- cedure,’ -j with the potential risk of impaired postopera- tive coronary perflusion due to kinking, distortion, steno- sis. or compression of the coronary arteries.“.‘Thc dcvcl- opment of late coronary stenosis and subsequent therapy is still a matter of conccm.6,7 We report our experiences with percutaneous transluminal coronary angioplasty in 4 infants aged 4 weeks to 15 months with proximal coro- nary stenoses after the arterial switch operation.

F,o- -be S-arik, Depcrtmen: of Pediatric Card:ology of the Hum- xldtL!wers’ty Schunlcrlr,strasse 20-2 ’ Berlin, r)-! 0 I 17 Gw-any. ~/wuscr~~: rcccl\~cd Ap:‘i 4. 1995, rev sed mavuscrip! rece’ved and accc:~led 1x-e 2. -995.

. . . We report on 4 patients who had undergone anatom-

ic correction of simple d-transposition of the great arter- ies at the third to fifth day of life. The anatomy of the coronary arteries was normal in 3 patients with the right coronary artery arising from the right-facing sinus, and the left main coronary artcry, from the left-facing sinus, while in 1 patient the left circumflex artery originated from the right coronary artcry. During anatomic correc- tion. the right coronary artery had been transferred to the right anterior, and the left coronary artery to the left antc- rior sinus of the neoaorta. The postoperative course was uncomplicated in all patients, right and left ventricular function being normal after surgery.

Cardiac catheterization was performed in 2 patients 4 and 6 weeks after surgery because left ventricular func- tion had deteriorated (fractional shortening 21% and 24%). In another patient, catheterization was performed

TABLE I Coronary Angioplasty After Arterial Switch Operation’

Before Angioplasty Angioplasty Follow-up

Coronow

Patient Number Age

Diameter Coronary Degree of Balloon Inflation Residual Time Residual Diamete; Site of of Stenosis Diameter Stenosis Diameter Pressure Stenosis lntervol Stenosis at Stenosis

Stenosis lmml bd (“4 lmm) bm) (“/I bo) (“w lmml

1 6wk LM 0.2 1 .3 85 2.0 6 8 12 0 2.5 2 4 wk LAD 0.3 1 .4 79 2.07 6 7 4 6 1.6 3 3mo LM 0.2 1.5 87 2.33+ 12 7 2 6 1.5 A 15 mo Right 0.5 1.9 74 2.33 12 10 3 5 2.0

‘Diomelers were measured from the digital angiograms after intracoronary administration of 0.1 Fg/kg nitroglycerin. ‘Initial balloon diameter was 1.5 mm. Coronary ongioplosty was repeated using o larger balloon diameter because of residual stenosis. Coronary Diameter = diameter of the coronary artery immediately behind the stenosis; Degree of Stenosis = stenosis of the poststenotic coronary diameter;

LM = left main coronary artery, LAD = leh anterior descending coronary artery (in potlent 2, the leh circumflex coronary artery originated from the right coronary artery]; Right = right main coronary artery; Time Interval = time interval between coronary angioplosty ond repeat cotheterizatlon

15 months after surgery because of bilateral pulmonary branch stenosis and right ventricular dilation, and in the last patient, as routine follow-up investigation 3 months after surgery (Table I). No electrocardiographic changes suggestive of myocardial ischemia8 or elevated creati- nine phosphokinase levels were observed. Cardiac cathe- terization was performed during mild sedation. Selective coronary angiography (4Fr modified right Amplatz cath- eter, SR 3-208, Cordis, Miami, Florida) revealed critical stenoses of the left (n = 3) and right (n = 1) main coro- nary artery in close proximity to the neoostium, ranging from 74% to 87% (Figures 1 and 2) (Table I). Coronary angiograms were repeated after intracoronary adminis- tration of 0.1 pg/kg nitroglycerin to relieve spasm, Ret- rograde filling of the obstructed coronary artery occurred in 2 patients. The ventricular angiograms revealed abnor- mal regional wall motion in 1 patient and global dys- function with ventricular dilation in 2 patients.

Because of the small diameter of the peripheral coro- nary artery, a decision was made to perform balloon angioplasty. Informed consent was obtained from all par- ents, After intravenous administration of 200 U/kg heparin and 1 mg/kg lidocaine, a 4Fr modified right Amplatz catheter (SR 3-208, Cordis) was positioned with

FIGURE 1. Selective coronary angiograms of the left main coro- nary arterj before and after angioplasty (4Fr catheter). A, 6 weeks after an arterial switch operation, there is a significant, circumscript stenosis in close proximity to the coronary neoost- ium in this 6-week-old infant. Subsequent balloon angioplasty was r-formed with a balloon diameter of 2 mm. B, 12 mon tr s after percutaneous transluminal angioplasty, there is no residual stenosis and normal growth of the left main coro- nary artery to a diameter of 2.5 mm.

622 THE AMERICAN JOURNAL OF CARDIOLOGY@ VOL. 76

its tip in close proximity to the stenotic coronary ostium and used as a guiding catheter for a fixed-wire balloon catheter (balloon diameter 1.5 to 2.0 mm, ACE Elite, Scimed, Maple Grove, Minnesota). The balloon was in- flated for 8 to 25 seconds within the stenosis by using inflation pressures between 6 and 12 atmospheres (Table I). In 2 patients, the initial balloon diameter had been 1.5 mm; in these, coronary angiograms after coronary angioplasty still revealed significant stenoses (>70%), thus angioplasty was repeated using a larger balloon, which was inflated to 2.0 and 2.33 mm (Figure 2). The residual stenoses ranged from 7% to 10% (Table I). No rhythm disturbances occurred during or after the coro- nary angioplasty. In patient 4, balloon angioplasty of the right pulmonary branch and stent implantation into the left pulmonary branch were additionally performed. Af- ter angioplasty all patients received 600 III/kg heparin intravenously for the lirst 24 hours, followed by 400 III/kg/day and finally 200 IU/kg/day intravenously. Ni- troglycerin 5 pg/kg/min was administered intravenous-

FIGURE 2. Coronary angiograms of the left main coronary artery before and after angioplas

x (4Fr catheter). A, 3 months

after on arterial switch operation t ere is a significant circum- script stenosis in close proximity to the coronary neoostium in this 3-month-old infant. Ventricular function was normal. Initial coronary angioplasty using a balloon diameter of 1.5 mm was unsuccessful, so that coronary angioplasty was repeated using a balloon diameter of 2.33 mm and an inflation pressure of 12 atrn. 6, 2 months later there is no significant stenosis of the left main coronary artery.

SEPTEMBER 1.5, 1995

ly for 2 days. Oral administration of 3 mg/kg aspirin and 2 mg/kg dipyridamole was initiated the day after coro- nary angioplasty and was continued for 6 months.

During follow-up, sequential echocardiograms de- monstrated normalization of left ventricular function in all patients within 2 weeks (fractional shortening >33%). However, the right ventricle in patient 4 remained en- larged. After 2 to 12 months coronary angiograms were repeated; they revealed no restenosis, but did show growth of the previous stenotic segment (Figures 1 and 2) (Table I). No echocardiographic or electrocardio- graphic abnormalities were observed during the follow- up period of 7 to 15 months.

. . . Although rare, coronary stenosis can develop weeks

or even months after the arterial switch procedure with- out overt clinical symptoms, and seems to be a risk fac- tor for late mortality. 2,5,9~10 Theoretically, coronary steno- sis could be due to thrombus formation or intima pro- liferation, but it seems more reasonable that this type of stenosis results from scar formation surrounding the proximal part of the surgically mobilized and reim- planted coronary artery, the ultrastructure of the vessel being normal.4*9 We performed overexpansion of the stenoses during angioplasty with a balloon-to-postste- notic coronary diameter ratio of 1.2 to 1.5. To minimize intimal laceration of the poststenotic coronary artery and to reduce the risk of dissection, only % of the balloon was positioned within the coronary artery. Despite our limited data and follow-up period, it can be speculated that coronary angioplasty is an effective therapy for coro- nary stenosis after the arterial switch procedure for com- plete d-transposition of the great arteries.

Coronary balloon angioplasty seems to be an ade- quate therapy for proximal coronary stenoses devel- oping after the arterial switch operation, with ade- quate medium-term results. Overexpansion of the lesion seems to be necessary.

1. Mayer JE, Sanders SP, Jonas RA, Castaneda AR, Wemovsky G. Coronary artery pattern and outcome of arterial switch operation for transposition of the great tier- ies. Circularion 1990;82(suppl IV):IV-139%IV-145. 2. Serraf A, Lacour-Gayet F, Bmniaux J, Touchot A, Losay J, Comas J, Sousa- Uva M, Planche C. Anatomic correction of transposition of the great arteries in neonates. J Am Coil Cavdiol 1993;22:193-200. 3. Di Donate RM, Wemovsky G, Walsh EP, Colan SD, Lang P, Wessel DL, Jonas RA, Mayer JE Jr, Castaneda AR. Results of the arterial switch operation for trans- position of the great arteries with ventricular septal defect. Surgical considerations and mid-term follow-up data. CircuIarion 1989;80:1689-1705. 4. Goor DA, Shem-Tov A, Neufeld HN. Impeded coronary flow in anatomic COT- ration of transposition of the great arteries: prevention, detection and management. J 7’horac Cardiovasc Surg 1982;83:747-754. 5. Kirklin JW, Blackstone EH, Tchervenkov Cl, Castaneda AR. Clinical outcomes after the arterial switch operation for transposition. Patient, support, procedural, and institutional risk factors. Congenital Heart Surgeons Society. Circularion 1992;86: 1501-1503. 6. Hayes AM, Baker EJ, Kakadeker A, Parsons JM, Martin RP, Radley-Smith R, Our&i SA. Yacoub M. Maislv MN. Tvnan M. Influence of anatomic correction fir transposition of the ireat a;eries bn’myocardial perfusion: radionuclide imag- ing with technetium-99m 2.methoxy isobutyl isonitrile. .I Am Coil Cardiol 1994; 24~769-777. 7. Weindlinz SN. Wemovskv G. Golan SD. Parker JA. Boutin C. Mone SM. Costel- lo J, Castaneda AR, Treves ST. Myocardial perfusion, function’ and exercise toler- ance after the arterial switch operation. JAm Coil Cardiol 1994;23:424-433. 8. Towbin JA, Bricker JT, Garson A Jr. Electrocardiographic criteria for diagnosis of acute myocardial infarction in childhood. Am J Cardiol 1992;69:1545-1548. 9. Allada V, Jarmakani JM, Yeatman L. Percutaneous transluminal comnay angio- plasty in an infant with coronary artery stenosis after arterial switch. Am Heart J 1991;122:1464-1465. 10. Bjoerkhem G, Evander E, White T, Lundstmem NR. Myocardial scintigraphy with 201.thallium in pediatric cardiology: a review of 52 cases. Pediatr Cardiol 1990;11:1-7.

Role of Papillary Muscle Position and Mitral Valve Structure in Systolic Anterior Motion of the Mitral Leaflets in Hyperdynamic Left Ventricular Function

Ramdas G. Pai, MD, Woravut Jintapakorn, MD, Masato Tanimoto, MD, and Pravin M. Shah, MD

S ystolic anterior motion (SAM) of the mitral valve with dynamic left ventricular (LV) outflow tract

obstruction results from hyperdynamic LV function, but not all patients with hyperdynamic LV function have SAM. Although certain structural features predispose to SAM, the precise anatomic substrate responsible for it is unsettled. Patients with both obstructive and nonob- structive types of hypertrophic cardiomyopathy are known to have longer mitral leaflets, larger leaflet areas, and greater incidence of abnormalities of papillary mus- cle insertions compared with controls.1,2 It has also been reported, based on in vitro studies, that anterior dis-

From the Sections of Cardiology, Jerry L. Pettis Veterans Affairs Hos- pital and toma Linda University, toma Linda, California. Dr. Pai’s address is: Cardiology /l 1 lC), Jerry L. Pettis Veterans Affairs Hos- pital, 1 1201 Benton Street, toma Linda, California 92357. Manu- script received April 6, 1995; revised manuscripi received and accepted June 19, 1995.

placement of the papillary muscles or lengthening of either of the mitral leaflets may cause SAM to occur.3 However, the exact positions of the papillary muscles and their relation to other potential mechanistic sub- strates responsible for SAM have not been clearly elu- cidated in vivo. This study examines the anatomic fac- tors that predispose to SAM in the presence of hyperdynamic LV function.

. . . The echocardiographic database was screened for

patients with hyperdynamic LV function (ejection frac- tion >80%) and dynamic intraventricular gradient at any level, with a flow velocity >2 m/s either at rest or with provocative measures such as the Valsalva maneuver, amyl nitrite inhalation, or dobutamine infusion. Sixty- three patients met these criteria and 31 of these had ade- quate echocardiographic images during production of intraventricular gradients for reliable anatomic and LV

BRIEF REPORTS 623