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Table of Contents
CASE REPORT
Year : 2022  |  Volume : 13  |  Issue : 1  |  Page : 51-56

Simplified art of balloon pulmonary valvuloplasty: Does the presence of mild supravalvular pulmonary stenosis preclude successful balloon pulmonary valvuloplasty?


Department of Cardiology, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India

Date of Submission04-Jul-2021
Date of Decision23-Sep-2021
Date of Acceptance01-Oct-2021
Date of Web Publication19-Jan-2022

Correspondence Address:
Dr. Debasish Das
Department of Cardiology, All India Institute of Medical Sciences, Bhubaneswar - 751 019, Odisha
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/injms.injms_76_21

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  Abstract 


We present a case of successful balloon pulmonary valvuloplasty (BPV) in a 37-year-old female with severe valvular pulmonary stenosis with peak gradient of 82 mmHg with history of exertional presyncope. The crux of our case was that patient also had associated mild supravalvular pulmonary stenosis which did not preclude a successful BPV outcome. The patient had rare Bombay negative blood group, and the requisite units were not available across all the blood banks in the state to subject the patient for surgical correction. Although the art of BPV is dying among budding young interventionists, this simple procedure is as good as surgical pulmonary valvotomy so far as the immediate and late outcome is concerned and the presence of mild supravalvular pulmonary stenosis does not preclude a successful outcome. Our case is a unique illustration of feasibility of successful balloon pulmonary valvuloplasty in the presence of associated mild supravalvular stenosis.

Keywords: Balloon pulmonary valvuloplasty, Pulmonary valve, Pulmonary stenosis, Valvular stenosis


How to cite this article:
Das D, Acharya D, Das T, Pramanik S. Simplified art of balloon pulmonary valvuloplasty: Does the presence of mild supravalvular pulmonary stenosis preclude successful balloon pulmonary valvuloplasty?. Indian J Med Spec 2022;13:51-6

How to cite this URL:
Das D, Acharya D, Das T, Pramanik S. Simplified art of balloon pulmonary valvuloplasty: Does the presence of mild supravalvular pulmonary stenosis preclude successful balloon pulmonary valvuloplasty?. Indian J Med Spec [serial online] 2022 [cited 2022 Jun 30];13:51-6. Available from: http://www.ijms.in/text.asp?2022/13/1/51/335972




  Introduction Top


Balloon pulmonary valvuloplasty (BPV) was introduced to the world of intervention about two decades ago and has revealed similar outcome to surgical pulmonary valvotomy so far as the immediate and late outcome is concerned. Pulmonary valvuloplasty results in universal pulmonary regurgitation, but this is of less clinical significance because 85%–90% of right ventricular ejection fraction flows to the pulmonary capillary bed and only 10%–15% remains in the pulmonary artery at very low-end diastolic pressure. Previously, indication of BPV was an invasive hemodynamic peak-to-peak gradient of 50 mmHg which correlates well with the peak systolic gradient (PSG) in echocardiography. Under sedation in cardiac catheterization laboratory, the same patient with an echocardiographic peak-to-peak gradient of 50 mmHg in awake state reveals a peak-to-peak gradient of 35 mmHg or less during sedation. With much favorable experience with BPV, now the indication of BPV is less stringent with an echo estimated gradient of 35 mmHg or more in an awake patient with objective sign of right ventricular hypertrophy in echo or electrocardiography (ECG). The procedure is carried out with generous local anesthesia while monitoring pulse oximetry and invasive blood pressure with an arterial pressure line. Infants and unstable patients are placed under general anesthesia; small children need intubation and controlled ventilation, with deep sedation without general anesthesia being necessary. Right ventricular angiocardiogram is performed with a 5F pigtail catheter in posteroanterior and lateral view, but pulmonary valve annulus is best measured in lateral view as the distance between the hinge points of the valve leaflets at the base of the pulmonary valve sinus measured at end systole. A lead marker is kept in lateral projection to know the exact position of valve leaflets during pulmonary valve balloon dilation. Although the procedure is simple, the presence of moderate or severe supravalvular stenosis or supravalvular membrane warrants surgical pulmonary valvulotomy. In spite of the presence of mild supravalvular pulmonary stenosis which obviates a nonfavorable outcome, we could successfully dilate the valve with a 16 mm × 4 cm Tyshak balloon with good post procedural outcome.


  Case Report Top


A 37-year-old female with a history of recurrent exertional presyncope with ECG evidence of right ventricular hypertrophy was subjected for echocardiography. Echocardiography revealed severe valvular pulmonary stenosis with thick and doming pulmonary valve leaflets with a peak systolic gradient of 82 mmHg [Figure 1] and normal right ventricular systolic function. The paradox of our case was she had also mild supravalvular pulmonary stenosis [Figure 2] and [Figure 3] without any membrane. Echocardiography revealed valve annulus to be of 14 mm, nondysplastic pulmonary valve with the presence of post stenotic dilatation, and normal pulmonary branch vessels. She had Bombay negative blood group for which surgeons were pretty reluctant to do a surgical pulmonary valvulotomy due to nonavailability of four units of blood even across all red cross centers in the state. As pulmonary artery disruption is rare event, in spite of the presence of mild supravalvular pulmonary narrowing, we proceeded for BPV for the same after crossmatching one unit of blood.
Figure 1: Severe valvular pulmonary stenosis with gradient of 82 mmHg

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Figure 2: Presence of mild supravalvular narrowing in parasternal short-axis and modified apical four-chamber view

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Figure 3: Mild supravalvular pulmonary stenosis in pulmonary angiogram in AP view with post stenotic dilatation in lateral view

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Procedure

Most centers perform a single-balloon dilatation of the pulmonary valve although double-balloon technique was the preferred method by great interventionists like Charles E. Mullins. We punctured the right femoral vein after generous local anesthesia (10 ml of injection Xylocaine with 1:1 dilution). Recommended sheath size for 16-mm balloon was 8F; we introduced 1F larger sheath size, i.e., 9F, to retrieve the folded balloon post dilatation. Although previously sheathless approach was a routine, use of a sheath prevents trauma to the femoral vein by the rough profile of deflated balloon. RV angiogram was done with 5F pigtail catheter with 30 ml of iodinated contrast at 12 ml/min with a pressure of 800 psi. Lateral view was taken and pulmonary annulus was measured end systole which came out to be 14 mm with mild supravalvular narrowing with huge post stenotic dilatation of main pulmonary artery [Figure 3]. In view of the presence of associated mild supravalvular stenosis, we decided not to much oversize the balloon and decided to dilate with a 16 mm × 4 cm balloon. By rule, the appropriate size of the balloon needed is 120% of the measured annulus diameter for effective dilatation. 5F Judkins Right (JR) catheter was torqued into the right ventricle with over a 0.35 J tipped 260-cm exchange length Terumo wire and a clockwise torque of the catheter in mid RV with slight pullback directed the JR catheter posteriorly toward right ventricular outflow tract (RVOT) and the pulmonary valve was crossed with this exchange length 0.35 exchange length Terumo wire and the wire was parked in the most distal branch of the left pulmonary artery till the floppy tip of the wire folded or bailed up in a stable position with bent J tip upward and JR catheter was advanced over this Terumo wire till the distal end and exchanged with a 0.35 exchange length Amplatz Extra Stiff (AES) wire. It is always easy to cross the pulmonary valve with a JR catheter and a J tipped Terumo wire. In difficult cases multipurpose catheter with a straight tip Terumo wire or in extreme difficulty routine J tipped 0.35 diagnostic wire may suffice in crossing the pulmonary valve. While passing the wire or balloon, no undue resistance should be felt which indicates wire entrapment in chordee or trabeculae. If at all undue resistance is felt during passage of wire, the procedure can be repeated to ensure the smooth passage of wire and catheter. Although recommended balloon diameter is 20% larger than the annulus diameter, pulmonary valve balloon dilatation can be successfully accomplished with 30%–50% larger balloon also. Recommended contrast dilution for preparation of BPV balloon is 1:5 because stuck balloon in RVOT is a catastrophe. Over this Amplatzer extra stiff (AES) wire, balloon was advanced. Once the balloon advances, the S loop of the wire straightens. Stretching or bowing of the Amplatzer extra stiff (AES) wire in the atrium or the ventricle presses the intracardiac conduction tissue, causes varying degree of heart block and ectopic rhythm in the form of right ventricular outflow tract premature ventricular complexes (PVCs), sinus bradycardia, or rarely cardiac arrest with the need of cardiopulmonary resuscitation (CPR). Therefore, it is always wise to preload with atropine and fast intravenous (IV) fluid (normal saline) before advancing the balloon. Position of the balloon across the valve is confirmed in reference to sternum, ribs, vertebrae, or cardiac silhouette in previously stored cine angiogram. Placing of the balloon across the valve clearly delineated the stenotic orifice with mild indentation from supravalvular narrowing [Figure 4]. Once it is confirmed that balloon is across the valve, balloon is inflated till the waist disappears [Figure 5], balloon gets straightened and then it is deflated very rapidly. The total duration of inflation and deflation during BPV should be <10–15 s. During inflation, sometimes, the balloon melon seeds to RVOT, that's why during balloon inflation both the AES wire and balloon are held with a forward pressure. If the balloon milks deep into the pulmonary artery, the AES wire is pushed so that balloon does not milk into the pulmonary artery. During inflation, if patent develops profound bradycardia or hypotension, then it is managed with atropine and bolus of IV fluid (500 ml normal saline). Transient desaturation may also occur which resolves spontaneously. Although successful BPV is defined as there should be only 10–15 mmHg residual gradient, in our case, peak systolic gradient came down to 28 mmHg [Figure 5]. Sometimes post successful balloon dilatation, gradient does not disappear as hypertrophied muscles in subvalvular area or infundibulum clamps down on itself resulting in suicidal right ventricle which is a normal phenomenon post surgical pulmonary valvotomy treated with beta-blocker and IV fluid. Best treatment of infundibular obstruction is time which heals everything. If balloon does not come out through the sheath, gentle counterclockwise torque wraps the balloon and both are removed in toto. Post BPV, pulmonary artery pressure rises along with systolic pressure. Echocardiography revealed mild residual pulmonary stenosis with peak gradient of 28 mmHg. If significant decrease in gradient does not occur post BPV, repositioning and expansion of the balloon can be accomplished 5–6 times to get favorable result. Sometimes critical pulmonary stenosis is of concern due to associated hemodynamic instability. It can be crossed with a coronary guidewire and dilated with a 2–3-mm coronary balloon to achieve hemodynamic stability. Once hemodynamic stability is achieved, larger wire, catheters, and balloons can be used to accomplish successful pulmonary valvuloplasty. In dysplastic valve, waist disappears during inflation and reappears during deflation. Pulmonary annulus rupture, pulmonary arterial injury, tricuspid valve injury, and insufficiency are rare events during BPV; real treatment of complication is prevention. In the event of wire passage through chordee, crossing the tricuspid or pulmonary valve can be accomplished with a balloon floating catheter-like  Swan-Ganz catheter More Details and gentle withdrawal of the balloon through tricuspid valve. In the event of resistance to withdraw the balloon, balloon is reinflated slightly, rotated in the direction of balloon fold, and withdrawing through the tricuspid valve gently and carefully. The presence of ASD or foramen ovale precludes BPV as it carries a risk of paradoxical embolization through the defect. The clue in our case was we did not oversize the balloon much due to the presence of associated supravalvular narrowing. Take-home message from our case is the presence of mild supravalvular pulmonary stenosis does not remain as a contraindication for doing BPV; we did not have any other option left as the patient had Bombay negative blood group which was not available to proceed for cardiac surgery.
Figure 4: Balloon across the pulmonary valve with small indentation from supravalvular component with successful balloon pulmonary valvuloplasty

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Figure 5: Post balloon pulmonary valvuloplasty mild pulmonary stenosis with peak systolic gradient of 28 mmHg

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  Discussion Top


The American Heart Association recommended the following indications of BPV.

  • Class I: Pulmonary valvuloplasty is indicated for a patient with critical valvar pulmonary stenosis (defined as pulmonary stenosis present at birth with cyanosis and evidence of patent ductus arteriosus dependency), valvar pulmonic stenosis, and a peak-to-peak catheter gradient or echocardiographic peak instantaneous gradient of > 40 mmHg or clinically significant pulmonary valvar obstruction in the presence of RV dysfunction (Level of Evidence: A)
  • Class IIa: (1) It is reasonable to perform pulmonary valvuloplasty on a patient with valvar pulmonic stenosis who meets the above criteria in the setting of a dysplastic pulmonary valve (Level of Evidence: C). (2) It is reasonable to perform pulmonary valvuloplasty in newborns with pulmonary valve atresia and intact ventricular septum who have favorable anatomy that includes the exclusion of RV-dependent coronary circulation (Level of Evidence: C)
  • Class IIb: Pulmonary valvuloplasty may be considered as a palliative procedure in a patient with complex cyanotic congenital heart disease, including some rare cases of tetralogy of Fallot (Level of Evidence: C)
  • Class III: Pulmonary valvuloplasty should not be performed in patients with pulmonary atresia and RV-dependent coronary circulation (Level of Evidence: B).


BPV is most often a safe procedure without notable complications. Complication occurs in only 8%–10% of cases, and the most common complication is perforation of the RVOT, which usually closes spontaneously or causes minimal pericardial effusion, and is most common in the first 3 months of life. Massive pericardial effusion rarely occurs either due to RVOT perforation or rupture of the pulmonary annulus due to oversizing of the balloon more than 150% of the pulmonary annulus diameter. Suicidal right ventricle or persistent infundibular spasm post pulmonary valvotomy occurs in few cases which responds to fluid therapy and beta-blocker. Transient bradycardia with hypotension during balloon inflation occurs due to complete occlusion of antegrade flow across pulmonary valve which recovers with fluid therapy and atropine. Cardiac or near cardiac arrest occurs in extremes of cases which usually recovers with resuscitation. Vascular complications including retroperitoneal bleed and iliac vein avulsion were common with older generation valvuloplasty catheters, but those are extremely rare with new generation valvuloplasty catheters. Limitations in performing a BPV include the presence of dysplastic pulmonary valve which is often nonrewarding.

The RVOT obstruction (RVOTO) in patients with intact ventricular septum is most commonly valvular, though both subvalvular and supravalvular obstructions are seen, especially in association with other anomalies. In patients with VSD and RVOTO, Fallot's tetralogy is the most common cause. Isolated valvular stenosis is a rarity in TOF patients. The index case had the classic valvular pulmonary stenosis with a high peak systolic gradient (PSG) of 82 mmHg which was more than 2/3rd of the systemic pressure (110/74 mmHg) prior to successful BPV. The angiographic images in the lateral view depict the doming of the pulmonary valve and the gross post stenotic dilatation of the PA which is classically seen in valvular PS. The supravalvular region demonstrates mild fibrotic narrowing with a very small shelf [Figure 2] suggestive of supravalvular pulmonary stenosis without any membrane, hourglass stenosis, or hypoplasia in the PA. The dome-shaped PV morphology is characterized by bowing of the PV leaflets into the pulmonary trunk caused by incomplete separation of valve cusps, coupled with preserved valvular motion [Figure 3]. In valvular pulmonary stenosis, the leaflets have varying degrees of fibrous thickening and are fused along their commissures. Dilation of the pulmonary artery is frequently present due to the eccentric flow resulting from the stenosis, as well as possible intrinsic connective tissue abnormalities within the pulmonary trunk itself.

The mechanism of balloon dilation of the cardiac valves is better exemplified by the more commonly applied and practiced procedure of rheumatic mitral stenosis (MS) dilatation Percutaneous transmitral commissurotomy (PTMC) Balloon mitral valvuloplasty (BMV). The congenital bicuspid aortic valve with severe aortic stenosis is also amenable to balloon dilatation. Whenever commissural fusion is the mechanism for the stenosis, ballooning of the valve provides good and lasting results. In cases of rheumatic MS with subvalvular involvement, the BMV results are not as good and procedure mostly required is surgical. Similarly the results of balloon dilatation are not good in dysplastic pulmonary valve (PV) morphology which accounts for 20% of valvular pulmonary stenosis (PS) and is commonly seen in patients with Noonan syndrome. The PV leaflets are prominently thickened with little or no commissural fusion and limited mobility. These valves do show balloon expansion during the dilatation, but the stenosis reappears post procedure because the underlying mechanism of valve stenosis remains as before.

The annular measurement in the lateral view is the gold standard. The substernal position of the pulmonary valve makes it the most difficult to study on a transthoracic echocardiogram. As a result, the angiographic measurements are the most accurate, especially in the case of pulmonary valve as against mitral and the aortic valve where the echo measurements are also considered accurate by most of the pediatric cardiologists. The balloon sizing of 110%–120% is the most commonly followed protocol for the adequate dilatation with the highest safety (least complications related to this procedure) at most of the pediatric catheterization laboratories.

The presence of significant supravalvular pulmonary stenosis remains a contraindication for doing BPV in adults. Supravalvular pulmonary stenosis remains as a membrane or shelf above the level of pulmonary valve which requires surgical excision during surgical pulmonary valvulotomy. Sometimes, supravalvular pulmonary stenosis remains as a tubular or hourglass narrowing of the supravalvular portion of the pulmonary artery; if at all dilated with a balloon, it may lead to rupture of the pulmonary trunk which may be catastrophic. However, the presence of mild supravalvular pulmonary stenosis does not preclude the procedural steps of pulmonary valvuloplasty because it does not exert much radial strain over the supravalvular portion of pulmonary artery and BPV can be smoothly accomplished. Our patient had Bombay negative blood group, even four units of crossmatched blood were not available across all red cross centers in the state. She was also not willing for midline sternotomy and surgical pulmonary valvulotomy; only option available for us was to do a BPV in spite of the presence of mild supravalvular narrowing. Congenital supravalvular PS is extremely rare and can be mistaken for valvular PS due to its close proximity to the pulmonary valve. Iatrogenic supravalvular PS can occur after procedures involving the main pulmonary artery (PA), such as arterial switch operation (as high as 20% of these patients in one report), repair of tetralogy of Fallot, and PA band placement.[1] Supravalvular PS can occur in patients with Williams-Beuren syndrome, though isolated supravalvular PS without distal stenosis is uncommon. BPV is not an effective intervention in cases of significant supravalvular PS, due to the close proximity of the stenotic area of the PA to the pulmonary valve. There are few available data on outcomes of children with supravalvular PS. One center reported that among infants and children who underwent repair of native supravalvular PS, no patients required re-intervention at 2 years.[1] In another single-center report of children with iatrogenic supravalvular PS after arterial switch operation, freedom from reoperation was 80% at 15 years and 66% at 20 years post repair.[2] As a consensus, the patient with severe subvalvular or supravalvular PS generally requires surgical correction since BPV is not effective in these cases,[3] But in our case, the indication of intervention was the presence of severe valvular pulmonary stenosis. Presence of mild supravalvular narrowing was not contributing towards the development of symptoms. Patient was also not suitable for surgical pulmonary valvulotomy due to nonavailability of Bombay Negative Blood Group. The presence of the rare blood group along increased the challenges posed by this patient. The simple clue in performing a BPV in the presence of supravalvular pulmonary stenosis is not to oversize the balloon by 130%–150%, as in the presence of tunnel-like supravalvular narrowing, it may rarely lead to rupture of the thin pulmonary artery which is a catastrophe. We recommend dilatation with a balloon of 100%–120% of the diameter of the pulmonary annulus to achieve good procedural success in the presence of associated mild supravalvular pulmonary stenosis. “Do not oversize the balloon to more than 120% in the presence of associated supravalvular pulmonary stenosis” is the key message for accomplishing a successful BPV in those cases. Khanra et al.[4] described a case of hourglass type of significant supravalvular pulmonary stenosis in a patient with congenital rubella syndrome (CRS). Our patient did not have any feature of CRS including deafness or cataract. In this hourglass type of supravalvular pulmonary stenosis, resection of the stenosing ridge, present just above the sinotubular junction of the main pulmonary artery along with autologous pericardial patch augmentation avoiding the level of annulus, is usually done. Supravalvular PS is a rare anomaly characterized by the stenosis of main, central branch, or peripheral branch pulmonary arteries either in combination or in isolation and is more commonly seen with CRS.[5] Multiple level stenoses are more common than an isolated obstruction in pulmonary artery.[5] Isolated supravalvular PS is more commonly acquired, and occurs after surgical intervention involving the main pulmonary artery.[6] Although supravalvar PS has been classically described in patients with Williams syndrome, its incidences had been quite rare. Rather, incidences of supravalvular aortic stenoses are more common in patients with Williams syndrome.[7] The presence of a hypertrophied ring of tissue at the sinotubular junction of the main pulmonary artery is characteristic of supravalvar PS which was well evident by mild indentation of the Tyshak balloon in pulmonary angiography.[8] The pulmonary valves may be thickened due to persistent trauma by the blood jet.[8] Supravalvar PS is usually surgically corrected with oval pericardial or Dacron patch.[1] Balloon dilatation for supravalvular PS usually fails most of the times because of the elastic recoil of the supravalvular ridge, and stenting should be avoided due to risk of stent migrating to injure to pulmonary valve.[9] Although surgical correction is the treatment of choice for significant supravalvular pulmonary stenosis, the presence of mild supravalvular narrowing cannot preclude a successful BPV.


  Conclusion Top


Our case is description of successful BPV in a case of severe valvular pulmonary stenosis with mild supravalvular narrowing in a patient with Bombay negative blood group for whom even four units of Bombay negative blood were not available to proceed for surgical correction. “Not to do too much oversizing of the balloon” was key to accomplish BPV in spite of the presence of mild supravalvular narrowing. The presence of mild supravalvular pulmonary stenosis does not preclude successful BPV when it becomes the need of the hour.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

None.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Bacha EA, Kalimi R, Starr JP, Quinones J, Koenig P. Autologous repair of supravalvar pulmonic stenosis. Ann Thorac Surg 2004;77:734-6.  Back to cited text no. 1
    
2.
Jatene MB, Jatene IB, Oliveira PM, Moysés RA, Souza LC, Fontes V, et al. Prevalence and surgical approach of supravalvular pulmonary stenosis after Jatene operation for transposition of great arteries. Arq Bras Cardiol 2008;91:17-24.  Back to cited text no. 2
    
3.
Rao PS, Galal O, Patnana M, Buck SH, Wilson AD. Results of three to 10 year follow up of balloon dilatation of the pulmonary valve. Heart 1998;80:591-5.  Back to cited text no. 3
    
4.
Khanra D, Shrivastava Y, Duggal B, Soni S. Congenital supravalvular and subvalvular pulmonary stenosis with hypoplastic pulmonary annulus associated with congenital rubella syndrome. BMJ Case Rep 2019;12:e231008.  Back to cited text no. 4
    
5.
Oster ME, Riehle-Colarusso T, Correa A. An update on cardiovascular malformations in congenital rubella syndrome. Birth Defects Res A Clin Mol Teratol 2010;88:1-8.  Back to cited text no. 5
    
6.
Yuan SM. Supravalvular pulmonary stenosis: Congenital versus acquired. Acta Med Mediterr 2017;33:849.  Back to cited text no. 6
    
7.
Eronen M, Peippo M, Hiippala A, Raatikka M, Arvio M, Johansson R, et al. Cardiovascular manifestations in 75 patients with Williams syndrome. J Med Genet 2002;39:554-8.  Back to cited text no. 7
    
8.
Kumar V, Mahajan S, Jaswal V, Thingnam SK. Surgical outcome of isolated congenital supravalvular pulmonary stenosis: A case series. Eur Heart J Case Rep 2019;3:ytz012.  Back to cited text no. 8
    
9.
Fogelman R, Nykanen D, Smallhorn JF, McCrindle BW, Freedom RM, Benson LN. Endovascular stents in the pulmonary circulation. Clinical impact on management and medium-term follow-up. Circulation 1995;92:881-5.  Back to cited text no. 9
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]



 

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