Article Type: Review
ReceivedDate : May 24, 2018
AcceptedDate : July 05, 2018
PublishedDate : July 10, 2018
Corresponding author: Ageliki A Karatza*
Department of Paediatrics, University of Patras Medical School, Patras, Greece
Article Type: Review
ReceivedDate : May 24, 2018
AcceptedDate : July 05, 2018
PublishedDate : July 10, 2018
Key words:patent ductusarteriosus;adult congenital heart disease; transcatheter occlusion; surgical ligation; subacute infective endocarditis/endarteritis; pulmonary hypertension; Eisenmenger syndrome; amplatzer duct occlude
The ductus arteriosus is a vascular structure which derives from the distal portion of the left sixth embryonic arch and connects the junction of the main and left pulmonary artery to the descending aorta distal to origin of the left subclavian artery (1-3). This process is necessary for normal fetal circulation and intra-uterine survival (1). In fetal life, the arterial duct allows for oxygenated blood to bypass the hypertensive pulmonary circulation, since the lungs are not involved in gas exchange and enter the systemic circulation. After birth, the arterial duct closes via a complex biphasic process and becomes the ligamentumarteriosum(4).
The ductus arteriosus closes spontaneously in about 95 % of full-term infants during the first 72 hours of life (5). Persistent patency beyond the third month in term infants is a common form of congenital heart disease with an incidence of 1 to 2000 subjects and represents 5% to 10% of all congenital cardiovascular abnormalities (1-3). Because the ductus arteriosus is a fetal structure, its occurrence is more frequent in children and there is a low incidence in adults, either because of spontaneous or surgical/interventional closure. Persistent patency of the ductus arteriosus is the most common cardiovascular problem of preterm neonates, with an incidence as high as 33% in infants
PDA can be associated with a variety of congenital anomalies of the heart, however, in the adult it is usually an isolated finding(7).Herein, current attitudes and controversies concerning the management of the adult patient with a PDA are discussed.
The adult with a PDA
Physical examination findings depend on the size of the PDA and the associateddefects.A small PDA presents with a continuous “machinery” murmur which is heard best heard best at the left infraclavicular area. In case of a large duct with pure left-to-right shunt, besides the classic “machinery” murmur, there may be bounding peripheral pulses due to a hyperdynamic circulation and a wide pulse pressure. Adults with a large, nonrestrictive PDAhowever,may have suprasystemicpulmonary artery pressure and develop Eisenmengerphysiology with a right-to-left shunt; in these patients the continuous “machinery” murmur is no longer audible. They may develop differentialcyanosis, with more profound desaturation of the lower extremities associated withclubbing which is more prominent in the toes. This represents themost specific physical sign of a large PDA associated with shunt reversal(8).
A trivial arterial duct is usually detected incidentally on transthoracic echocardiography performed for other purposes. When the duct becomes very small, flow through it is diminished and non-turbulent, and thus no murmur is audible. The very small duct which is identified incidentally in asymptomatic subjects and produces no murmur on auscultation is termed “the silent duct” (9, 10).
The mortality in adults with an unoperatedPDA is estimated to be 1–1.5% in the third decade, 2–2.5% in the fourth decade and increases by 4% per year thereafter, with 33% mortality at the age of 40 and 60% at 60 years of life(11).Untreated PDA may causecongestive heart failure due to left heart volume overload and increased pulmonary blood flow, atrial fibrillation or flutter due to atrial enlargement, infective endocarditis/endarteritis which is more common in second or third decade of life, lower respiratory tract infections, calcification and pulmonary vascular disease/Eisenmenger’ssyndrome. Other more uncommon complications include aneurysmal dilatation of the duct, recurrent laryngeal nerve paralysis due to compression from a dilated pulmonary artery, peripheral emboli, and exceedingly rarely aortic or pulmonary artery dissection(8, 9, 10).
Echocardiography is the key diagnostic imaging modality; however, it may be difficult in patients with Eisenmenger physiology(12). Echocardiography defines the presence and the size of the PDA, the effect of the shunt on the left atrium and left ventricle, the pulmonary circulation, and any associated lesions(10, 13).
The echocardiographic diagnosis is based on 2D images demonstrating an anatomic connection between the descending aorta and the pulmonary artery, which is identified with the use of colour Doppler. The best images are obtained in the high left parasternal short-axis view above the level of the aortic valve, with the ultrasound probe placed under the left clavicle (“the ductal shot”). The ultrasound beam is aligned into the orifice of the PDA, the Doppler sample volume is placed just proximal to the bifurcation of the pulmonary artery, and systolic and diastolic PDA flow is estimated. Alternatively, using the suprasternal view which may be modified to achieve a long-axis view of the right ventricular outflow tract and the main pulmonary artery, both the aortic end and the pulmonary ends of the PDA may be seen. Pulsed-wave Doppler from the suprasternal view is used to demonstrate flow reversal in the descending aorta due to antegrade flow into the PDA during diastole (14).
When the quality of the echocardiogram is poor or when echocardiographic measurements are borderline or ambiguous, cardiac magnetic resonance (CMR) becomes necessary. Computed tomography (CT) is reserved to obtain information unavailable by echocardiography in patients with implanted pacemakers or defibrillators who cannot be imaged with CMR (7, 15). MRI or CT are indicated to evaluate pulmonary artery anatomy or to obtain more precise left ventricular volumes(7, 15)(Table).
Cardiac catheterisation is reserved for cases with signs of pulmonary hypertension on echocardiography to estimate pulmonary vascular resistance and assess the reactivity of the pulmonary vascular bed(10, 12).
Catheter interventional occlusion is the treatment of choice, even if operation for associated anomalies has been scheduled. Techniques have evolved overtime and transcatheterocccclusion is now feasible and safe with the currently available devices. Coils and the Amplatzer Duct Occluder are used most frequently for PDA closure, with a high occlusion rate and few complications 16).Various devices may be used to occlude a PDA depending on its morphology. Coil occlusion is a safe and effective procedure for small PDAs. Otherwise the Amplatzer duct occluder (ADO) is the most commonly used device worldwide (16).
In general, for the older adult with a PDA, transcatheter closure is the preferred approach, which is safe and effective with the ADO being the most-used device in this age group. Ductal anatomy may differ from that seen in childhood, making transcatheter closure technically much more difficult than in children (2).
In adults the duct is often calcified and the tissue in the area of the aortic isthmus and pulmonary artery is friable, making surgical ligation difficult and more hazardous compared to paediatric patients (10, 12). Surgical ligation is thus reserved for patients with very large ducts, those with difficult anatomy or aneurysmal dilatation(2, 12).
PDA occlusion eliminates volume overload of the left ventricle and pulmonary over-circulation, treats congestive heart failure and prevents both the development of obstructive pulmonary vascular disease/Eisenmenger syndrome and subacute endocarditis/endarteritis (1, 2, 3, 6).
According to the guidelines of the American heart Association (AHA), transcatheter PDA occlusion is considered reasonable in the presence of a small left-to-right shunt with normal-sized heart chambers, when the PDA is audible by standard auscultation techniques (6).Small PADs without haemodynamic overload are generally closed, because of the risk of subacute bacterial endocarditis (6, 12). There is still controversy related to the need of closure of a silent arterial duct which is associated with a small left-to-right shunt, a normal heart size and an inaudible murmur (Class of recommendation IIb; Level of evidence C) (6). According to the European Society of Cardiology (ESC), PDA should be closedin patients with left ventricular volume overload ((Level of Evidence I; Class of Recommendation C), device closure should be considered in small PDAs with a continuous murmur, normal LV and pulmonary artery pressure (Level of Evidence IIa; Class of Recommendation C), but should be avoided in the “silent duct” (Level of Evidence III; Class of Reccommendation C) (7).
Infective endocarditis in subjects with silent ducts has been reported only in single-case reports (17, 18). This was one of the reasons for the revision of the Infective endocarditis prophylaxis guidelines of the American Heart Association Committee on Rheumatic Fever, Endocarditis and Kawasaki disease, who do not recommend routine subacute bacterial endocarditis prophylaxis for unrepaired PDA(7). In the exceedingly rare case of an adult with previous endarteritis,closure of a PDA either percutaneously or surgically is indicated (7). On the contrary, PDA closure is contraindicated for patients with pulmonary arterial hypertension and pure right-to-left shunt(7).
A PDAis a cardiovascular disorder documented in patients of all ages, from extremely premature infants to elderly subjects (6, 15). Currently, the widespread availability of echocardiography has resulted in improved detection and detailed characterisation of the size of a PDA, the effects on the left atrium and left ventricle, the pulmonary circulation, and any associated lesions. The haemodynamicconcequences of PDA in adults are analogous to the magnitude and the direction of the shunt, which depend on the flow resistance within the duct, and the dynamic pressure gradient between the pulmonary and systemic blood flow (19).Catheter occlusion is the treatment of choice and surgical ligation is reserved for patients with very large ducts or when interventional closure is not feasible. However, the optimal management of the “silent arterial duct” remains controversial and requires further investigation.
1. Schneider DJ (2012) the patent ductusarteriosus in term infants, children and adults. SeminPerinatol 36: 146-153.
2. Schneider DJ, Moore JW (2006)Patent ductusarteriosus.Circulation114:1873-1882.
3. Anilkumar M (2013) Patent ductusarteriosus. CardiolClin 31: 417–430.
4. Huff T, Bhimji SS (2018)Anatomy, Thorax, Heart, Ductus Arteriosus.StatPearlsTreasure Island (FL): StatPearls Publishing;.
5. Kang C, Zhao E, Zhou Y, Zhao H, Liu Y, et al. (2016) Dynamic Changes of Pulmonary Arterial Pressure and Ductus Arteriosus in Human Newborns
from Birth to 72 Hours of Age.Medicine95: e2599.
6. Elsayed YN, Fraser D (2017) Patent Ductus Arteriosus in Preterm Infants, Part 1: Understanding the Pathophysiologic Link between the Patent
DuctusArteriosus and Clinical Complications. Neonatal Netw 36: 265-272.
7. Baumgartner H, Bonhoeffer P, De Groot NM, de Haan F, Deanfield JE, et al (2010) The Task Force on the Management of Grown-up
Congenital Heart Disease of the European Society of Cardiology (ESC). European Heart Journal: 31: 2915–2957.
8. Feltes TF, Bacha E, Beekman RH , Cheatham JP, Feinstein JA, Gomes AS, et al (2011)On behalf of the American Heart Association Congenital Cardiac
Defects Committee of the Council on Cardiovascular Disease in the Young, Council on Clinical Cardiology, and Council on Cardiovascular Radiology
and Intervention. Indications for cardiac catheterization and intervention in pediatric cardiac disease: a scientific statement from the
American Heart Association. Circulation. 123: 2607-2652.
9. Warnes CA, Williams RG, Bashore TM, Child JS, Connolly HM, et al (2008) Guidelines for the Management of Adults with Congenital Heart Disease.
A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines
(Writing Committee to Develop Guidelines on the Management of Adults with Congenital Heart Disease. Circulation118: 2395-2451.
10. Campbell M (1968) Natural history of persistent ductus arteriosus. Br Heart J 30: 4-13.
11. Wilson W, Taubert KA, Gewitz M, Lockhart PB, Baddour LM, Levison M, et al (2007)Prevention of infective endocarditis:
guidelines from the American Heart Association: a guideline from the American Heart Association Rheumatic Fever, Endocarditis,
and Kawasaki Disease Committee, Council on Cardiovascular Disease in the Young, and the Council on Clinical Cardiology,
Council on Cardiovascular Surgery and Anesthesia, and the Quality of Care and Outcomes Research Interdisciplinary Working Group.
12. Chugh R Salem MM (2014) Echocardiography for patent ductus arteriosus including closure in adults. Echocardiography00: 1-15.
13. Fadel BM, Mohty D, Husain A, Dahdouh Z, Al-Admawi M, etal(2015) The Various Hemodynamic Profiles of the Patent Ductus Arteriosus in Adults.
Echocardiography; 32: 1172-1178.
14. Chugh R, Salem MM (2015) Echocardiography for Patent Ductus Arteriosus including Closure in Adults. Echocardiography 32: 125-139.
15. Kilner PJ, Geva T, Kaemmerer H, Trindade PT, Schwitter J, Webb GD (2010). Recommendations for cardiovascular magnetic resonance in adults with
congenital heart disease from the respective working groups of the European Society of Cardiology.Eur Heart J31:794-805.
16. Baruteau AE, Hascoët S, Baruteau J, Boudjemline Y, Lambert V (2014)Transcatheter closure of patent ductus arteriosus.
Archives of Cardiovascular Disease 107: 122-132.
17. Ozkokeli M, Ates M, Uslu N, Akcar M(2004) Pulmonary and aortic valve endocarditis in an adult patient with silent patent ductus arteriosus.
Jpn Heart J 45:1057-1061.
18. Parthenakis FI, Kanakaraki MK, Vardas PE (2000) Images in cardiology: silent patent ductus arteriosus endarteritis.Heart 84: 619.
19. Boyalla V, Putzu P, Dierckx R, Clark AL, Pellicori P (2015)Patent ductus arteriosus in older adults: incidental finding or relevant pathology?
J Am GeriatrSoc63: 409-11.