The Intermittent Ductus Revisited: EchocardiographicEvidence and Successful Coil Occlusion: A Case Report and

Review of Literature

Rajiv Verma, 1 MD, Salvatore Presti, 2 MD, and Delores Danilowicz, 2* MD

Intermittent occurrence of a large ductal shunt by physical examination and Dopplerechocardiography is reported. Cineangiography confirmed a tubular ductus arteriosuswith an angulated, narrow, pulmonary end. Presumably this angulation intermittentlycaused functional closure of the ductus. Trans-arterial delivery of coils resulted incomplete occlusion. Cathet. Cardiovasc. Diagn. 45:260–263, 1998 . r 1998 Wiley-Liss, Inc.

Key words: congenital heart disease; interventional cardiac catheterization; intermittentductal shunt

INTRODUCTION

In the 1960s and 1970s, four reports appeared in theliterature attesting to the intermittency of ductal flow; allfour patients eventually had surgical ligation / division ofthe ductus [1–4]. In one child, an unusual valve wasdescribed at the pulmonary artery end of the ductus [2]while the others had a long ductus which appeared to beacutely angled at the pulmonary artery end [1,3,4]. Wenow report the first documentation of an intermittent largeductal shunt confirmed by physical exam and colorDoppler echocardiography, referred for coil occlusion.

CASE REPORT

C.R. is a 26-month-old female child who was bornprematurely at 36 weeks gestation, weighing 1.8 kg.Although mechanical ventilation was not required, dis-charge was delayed for a month due to poor feeding. Asignificant murmur was first heard at about 2 months ofage. Cardiac evaluation revealed an infant with hyperdy-namic peripheral pulses and a continuous murmur in theleft infra-clavicular region. Color Doppler echocardiogra-phy confirmed a large left to right ductal shunt (Fig. 1)with no other structural cardiac defects. Follow upevaluation was planned in a few months with the intent ofreferring for coil occlusion since the shunt appearedsignificant and the large ductus unlikely to close spontane-ously. However, when re-evaluated at about 1 year of age,no murmur was heard and Doppler echocardiographyfound no evidence of a ductal shunt (Fig. 2). This wasassumed to be late spontaneous closure and the child wasdischarged to the care of the pediatrician. On the nextroutine pediatric visit, the continuous murmur was heard

again and further cardiac evaluation re-confirmed find-ings of the first cardiac visit. She was then referred forductal coiling.

Catheterization data (Table I) confirmed a large left toright ductal shunt with no additional defects. Cineangiog-raphy demonstrated a long (18 mm) ductus, 9–10 mmdiameter at the aortic end, and 6 mm in diameter for mostof its length (Fig. 3a). At the pulmonary end, there wasacute angulation and decrease in the ductus lumen size to3 mm in the lateral plane. Delivery of 0.038-inch caliberGianturco coils was via the trans-arterial route with anassisting snare in the main pulmonary artery, as previ-ously described [5]. In spite of the smaller size at thepulmonary end, neither a 5 mmdiameter by 8 cm lengthnor a 6 mm by 8 cmcoil could be seated in the ductus;both of these coils passed through easily into the pulmo-nary artery with virtually no traction on the snare andwere extracted from the body uneventfully. An 8 mmdiameter by 10 cm length coil was then successfullyseated in the ductus. A significant residual shunt wasevident and two additional coils (6 mm3 8 cm, 5 mm38 cm) were deployed, using the first as a stabilizingframework. After placement of the third coil, only a trace

1Pediatric Cardiology, Children’s Hospital of New Jersey, New-ark, New Jersey.2Pediatric Cardiology, New York University Medical Center, NewYork, New York.

*Correspondence to: Delores Danilowicz, MD, Pediatric Cardiology,Skirball FPO Suite 9U, New York University Medical Center, 530 FirstAvenue, New York, NY 10016.

Received 9 March 1998; Revision accepted 4 June 1998

Catheterization and Cardiovascular Diagnosis 45:260–263 (1998)

r 1998 Wiley-Liss, Inc.

residual angiographic shunt was present (Fig. 3b); thus noadditional coil was attempted. Her postcatheterizationcourse was uncomplicated and Doppler echocardiogra-phy prior to discharge the following day excluded aresidual ductal shunt. There was no significant flowdisturbance into the branch pulmonary arteries or aroundthe aortic arch. A further echocardiogram 9 months afterthe procedure confirmed persistent resolution of thisductal shunt with no evidence of branch pulmonary arterystenosis or aortic arch flow disturbance.

DISCUSSION

Between 1960 and 1975, four reports of intermittentductal shunting appeared in the literature [1–4]. The first[1], in 1960, was of a 9-year-old girl who was aware of‘‘her washing machine’’ that came and went; a murmurfirst was heard at 2 years of age but was intermittentlyheard up to the time of referral for surgical division. Onadmission, a continuous murmur was heard but subse-quently disappeared and these changes were documented

Fig. 1. Color flow mapping and Doppler demonstrate flow through the ductus arteriosus. AO 5aorta. MPA 5 main pulmonary artery. PDA 5 patent ductus arteriosus.

Fig. 2 Color flow mapping and Doppler demonstrate no flow when murmur was absent. LPA 5left pulmonary artery. MPA 5 main pulmonary artery.

Intermittent Ductal Shunting 261

by phonocardiography. Although arriving to the catheter-ization laboratory without a murmur, it reappeared duringthe study and the ductus shunt was documented withsurgical division the following day. At the time ofoperation, a long ductus was described with acute angula-tion at the pulmonary end with just minimal tractioncausing the thrill to disappear. The second report [2] wasa 10-year-old girl, clinically diagnosed with a ductusarteriosus 6 months prior to her referral for surgicaldivision. The child, on admission, had no murmur heardbut on arrival in the phonocardiography laboratory, atypical continuous murmur was heard and recorded.Attempts with positioning were not successful in obliter-ating the murmur but on arrival back to the ward, themurmur was again absent. The parents refused permis-sion for a cardiac catheterization and when the murmuragain recurred, she was sent to the operating room. A longductus, about 2 cm, was found, with a palpable thrill andwas divided. A valve or veil like structure was describedat the pulmonary artery end. The third report [3], in 1967,actually documented intermittent shunting with two cath-eterizations, the first after a murmur was heard but notpresent when the 2.5-year-old boy appeared in thecatheterization laboratory. Neither dye dilution curvesnor oximetry on room air and on oxygen showed a shuntand change in position did not cause the murmur to recur.On arrival back in his room, the murmur was again heard,persisted, and 2 days later, a repeat catheterizationdemonstrated a large shunt through the ductus by oxim-etry and dye dilution curves. Aortic pulse pressure andpulmonary artery pressures were markedly different fromthe earlier study as well. At operation, the aortic end ofthe ductus measured 10–12 mm with a length of 20 mm.There was angulation at the pulmonary artery end due tothe redundancy of the ductus but no internal valve was

identified at the pulmonary artery end. A 3 mm by 12 mmsegment of the ductus, removed and sent to pathology,was interpreted as typical ductal tissue. The fourth report[4] documented a clinically intermittent ductus in aninfant. At catheterization, oximetry revealed no evidenceof shunting at the ductal level, a normal aortic pulsepressure and concomitant lack of a murmur. With thedelivery of high flow oxygen in the catheterizationlaboratory, the patent ductus arteriosus murmur recurred,oximetry confirmed a large left to right shunt at the ductallevel and the aortic pulse pressure widened. This was

TABLE I. Cardiac Cathete rization Data

SitePressure(mm Hg)

Saturation(%)

PrecoilingAorta 105/45, m5 72 96Main pulmonary artery 28/16, m5 20 88Pulmonary artery wedge a5 13, v5 20, m5 13Right atrium a5 7, v 5 6, m5 4 73Pulmonary blood flow (Qp)5 10.8 L/min/M2.Systemic blood flow (Qs)5 4.2 L/min/M2.Qp/Qs5 2.6/1Pulmonary vascular resistance5 0.65 Wood unitsSystemic vascular resistance5 16.2 wood units

PostcoilingAorta 125/78, m5 100 94Main pulmonary artery 34/16, m5 25 71Right atrium a5 10, v5 9, m5 6 71

Cardiac index5 3.9 L/min/M2.

Fig. 3. Aortic cineangiography: lateral view before (a) and after(b) coiling. Black arrowhead denotes the long patent ductusarteriosus. White arrow denotes the angulated end of the patentductus arteriosus.

262 Verma et al.

despite the pulmonary vascular resistance being normalpre- and postoxygen delivery. At surgery the ductus wasconfirmed to be long, tapering at the pulmonary end andwas ligated and divided.

Our patient had similar ductal findings to the first, thirdand fourth cases with a long ductus angulated at thepulmonary artery end. The clinical and echocardio-graphic documentation of lack of ductal flow at 1 yearwas proven not to be related to spontaneous delayedclosure of the ductus as has been reported in prematureinfants [6], since a large shunt recurred. By cineangiogra-phy the ductus measured 9–10 mm at the aortic end and 3mm at the pulmonary artery end, being sharply angulatedat its entry into the pulmonary artery. This angulation inductal tissue has been presumed to cause intermittentfunctional closure of the ductus and in the first casereported [1] minor traction in the operating room accom-plished this. One wonders, in retrospect, whether thevalve or veil like tissue described in the second casereport [2] was also a fold of ductal tissue at the pulmonaryartery end due to this redundancy and angulation.

Since the 5 mm and 6 mm diameter coils did not seat inthe ductus, the pulmonary artery end diameter of theductus was most likely functionally larger and laxity ofthe tissue allowed passage of these coils without resis-tance. The pulmonary artery end may be box or slit likeand thus the lumen size may be significantly larger thanthat measured in the lateral angiographic plane. An 8 mmby 10 cm coil was finally seated and two additional coilsdelivered within this matrix to almost totally occlude theductal shunt.

The combination of lengthy ductus with redundant orlax tissue at the pulmonary end may result in intermittentfunctional closure due to transient changes in pulmonaryor systemic vascular resistance. This is implied by thefourth report [4] where even in the presence of normalpulmonary vascular resistance initially, administration of

high flow oxygen probably altered the resistance enoughto allow for the ductus to shunt significantly. At herpresent age, our patient had a normal pulmonary vascularresistance but it is possible that at 1 year of age it mayhave been different and could have contributed to intermit-tent functional closure of the ductus. Furthermore, onemay also speculate that with patient growth, changes inintrathoracic pressure-volume physiology and cardiacposition may contribute to this phenomena of intermittentductal closure.

Doppler echocardiography the day following coilingconfirmed complete resolution of the ductal shunt andthis has persisted to at least the 9-month follow-up.Infective endocarditis prophylaxis for invasive proce-dures has since been discontinued.

ACKNOWLEDGMENTS

Assistance by Mr. Alan Katz and Peter Haddock,Ph.D., in the manuscript preparation is greatly appreci-ated.

REFERENCES

1. Shapiro W, Said SI, Nova PL: Intermittent disappearance of themurmur of patent ductus arteriosus. Circulation 22:226–231, 1960.

2. Keith TR, Sagarminaga J: Spontaneously disappearing murmur ofpatent ductus arteriosus: a case report. Circulation 24:1235–1238,1961.

3. Kohler CM, McNamara DG: Elongated patent ductus arteriosuswith intermittent shunting. Pediatrics 39:446–448, 1967.

4. DuBrow IW, Fisher E, Hastreiter A: Intermittent functional closureof patent ductus arteriosus in a 10-month-old infant: hemodynamicdocumentation. Chest 68:110–113, 1975.

5. Sommer RJ, Gutierrez A, Lai WW, Parness IA: Use of preformednitinol snare to improve transcatheter coil delivery in occlusion ofpatent ductus arteriosus. Am J Cardiol 74:836–839, 1994.

6. Danilowicz D, Rudolph AM, Hoffman JIE: Delayed closure of theductus arteriosus in premature infants. Pediatrics 37:74–78, 1966.

Intermittent Ductal Shunting 263