Transcatheter treatment of "pulmonary artery hypertension" due to patent ductus arteriosus and pulmonary artery stenosis

The association between large, left-sided patent ductus arteriosus and severe, peripheral, right pulmonary artery stenosis with no other cardiac malformation is an unreported condition that might be misdiagnosed as pulmonary hypertension due to long-standing ductal shunt. A 57-year-old man with supposed hypertensive patent ductus arteriosus underwent confirmatory cardiac catheterization. At angiography, a severe pre-hilar right pulmonary artery stenosis (peak pressure gradient, 65 mmHg) was found to complicate the hemodynamic picture of a moderate-to-large patent ductus arteriosus (QP/QS, 1.7:1), by causing pulmonary hypertension (mean pressure, 65 mmHg) and left-to-right pulmonary flow imbalance. Both lesions were treated in a single procedure of right pulmonary artery stenting and patent ductus arteriosus closure, after which the pulmonary artery pressure significantly decreased (mean, 35 mmHg). In our opinion, a thorough hemodynamic evaluation followed by pulmonary angiography should be mandatory before proceeding to patent ductus arteriosus closure in the adult patient who has "hypertensive" ductus, in whom possible associated malformations can be missed due to a poor echocardiographic window.     

Noninvasive Doppler echocardiographic evaluation of shunt flow dynamics of the ductus arteriosus

The pulsed Doppler technique was used to record the flow velocity patterns in the ductus arteriosus and the pulmonary artery in 26 patients with either isolated or complicated patent ductus arteriosus (PDA). In all patients, abnormal Doppler signals indicating left-to-right (L-R) or right-to-left shunt flow or both could be obtained at the site of the ductus arteriosus. These Doppler flow patterns determined within the ductus coincided with the direction of ductal flow seen on the contrast two-dimensional echocardiogram. No Doppler signals of shunt flow were demonstrated in any of 42 control subjects. The peak, mean, and diastolic velocities of the L-R shunt flow within the ductus were measured from the ductal flow velocity profiles. With the Doppler-derived measurements of the mean and diastolic velocities, patients with normal pulmonary arterial pressure and those with evidence of pulmonary hypertension could be correctly identified. In addition, the mean velocity of the diastolic antegrade flow portion obtained from the proximal left pulmonary artery, which was related to ductal L-R shunting, was measured in 16 patients with isolated PDA. This Doppler flow determinant showed a good linear correlation with the L-R shunt ratio determined by Fick's method (r = .88, p less than .01). Our technique permits the noninvasive evaluation of shunt flow dynamics in patients with PDA.     

Real-time Doppler color flow mapping for detection of patent ductus arteriosus

In this study, ultrasound Doppler color flow mapping systems were utilized to examine flow in the pulmonary artery in 31 premature and term infants (aged 4 hours to 9 months) with patent ductus arteriosus accompanying respiratory distress syndrome, as an isolated lesion, or with patent ductus in association with other cyanotic or acyanotic congenital heart disorders. The flow mapping patterns were compared with those of a control population of 15 infants who did not have patent ductus arteriosus. In unconstricted ductus arteriosus, the flow from the aorta into the pulmonary artery was detected in late systole and early diastole and was distributed along the superior leftward lateral wall of the main pulmonary artery from the origin of the left pulmonary artery back in a proximal direction toward the pulmonary valve. In constricted patent ductus arteriosus, or especially in a ductus in association with cyanotic heart disease, the position of the ductal shunt in the pulmonary artery was more variable, often directed centrally or medially. Waveform spectral Doppler sampling could be performed in specific positions guided by the Doppler flow map to verify the phasic characteristics of the ductal shunt on spectral and audio outputs. Shunts through a very small patent ductus arteriosus were routinely detected in this group of infants, and right to left ductal shunts could also be verified by the Doppler flow mapping technique. This study suggests substantial promise for real-time two-dimensional Doppler echocardiographic flow mapping for evaluation of patent ductus arteriosus in infants.     

Use of Amplatzer duct occluder to close severely hypertensive ducts: utility of transient balloon occlusion

BACKGROUND: The dividing line between a patent ductus arteriosus with severe but reversible pulmonary artery hypertension and an Eisenmenger duct remains elusive. Increasing experience with the Amplatzer duct occluder has made non-surgical closure of even large patent ductus arteriosus simple and safe. However, data on the use of this device in severly hypertensive ducti is sparse. METHODS AND RESULTS: There were six patients (2 males, 4 females), wherein transient ductal occlusion was done with an embolectomy balloon catheter. The post-occlusion hemodynamics along with overall clinical and hemodynamic assessment was used to decide the likelihood of benefit of closure and the choice of the device. In four of six patients of patent ductus arteriosus with severe pulmonary artery hypertension (pulmonary vascular resistance index> 8.0 U/m2) the duct was successfully closed using the Amplatzer duct occluder, while in two an Amplatzer ventricular septal defect occluder was used. CONCLUSIONS: Transient balloon occlusion is quite helpful for assessing patients with patent ductus arteriosus with severe pulmonary hypertension, and short-term non-invasive follow-up has shown this strategy to be safe and useful.     

Transcatheter closure of wide, patent ductus arteriosus in an adult patient with severe pulmonary hypertension-a case report

A case of a 49-year-old female with patent ductus arteriosus complicated by severe pulmonary hypertension is presented. The patent ductus arteriosus was successfully closed by the Amplatzer duct occluder. The physical capacity improved from functional NYHA class III at baseline to class I one month after the procedure. A significant reduction of systolic blood pressure in the pulmonary artery and pulmonary resistance was also observed. Indications for transcatheter closure of the patent ductus arteriosus in patients with severe pulmonary hypertension are discussed.     

Transcatheter closure of a large patent ductus arteriosus with the clamshell septal umbrella

In 14 patients undergoing transcatheter closure of a large (greater than 4 mm diameter) patent ductus arteriosus, occlusion was attempted with use of the Bard Clamshell septal umbrella. Patient age ranged from 0.7 to 30.4 years. Isolated patent ductus arteriosus was present in 11 patients; 3 had additional congenital heart lesions. Moderate or severe pulmonary hypertension was present in four patients. The diameter of the patent ductus arteriosus ranged from 4.5 to 14 mm, as determined by contrast injection through an 11F sheath or by balloon sizing; it appeared larger by this method than by the standard angiographic method. All 14 patent ductus arteriosi were successfully closed. Prior embolization of a Rashkind umbrella was the reason for using a Clamshell device in three patients; one additional embolization of a Clamshell device occurred. All errant devices were retrieved at cardiac catheterization, without associated hemodynamic instability. No other complications occurred. Among the 14 patients, 11 had complete ductal closure by Doppler color flow mapping at last follow-up and 3 had trivial residual flow. All four patients having associated complex lesions or pulmonary hypertension, or both, had symptomatic improvement after the procedure, although one child (with Shone's anomaly) died 3 months later. The Clamshell device provides stable and effective closure of a large patent ductus arteriosus, and allows transcatheter closure to be offered to some patients who were previously considered unsuitable for this procedure.     

Prevalence of additional cardiovascular anomalies in patients referred for transcatheter closure of patent ductus arteriosus

Catheter closure of the patent ductus arteriosus is now a reality. The purpose of this study was to establish the prevalence of associated cardiovascular defects and the accuracy of echocardiography in patients referred for transvenous ductal closure. This study reviewed 146 patients seen from 1981 to 1988: 126 with only a patent ductus arteriosus (Group I) and 20 with additional cardiovascular anomalies (Group II). Groups I and II did not differ significantly in age, gender or physical examination except for the presence of a continuous murmur (Group I 100% versus Group II 80%, p less than 0.001). A left patent ductus arteriosus was visualized by two-dimensional echocardiography in 96% of patients and was evident by Doppler study in 100%. A patent ductus arteriosus was not seen in six patients including a patient who was found to have only a collateral network from the aorta to the main pulmonary artery. The 12 patients with noncardiovascular abnormalities such as Down's syndrome were more likely than the overall group to have additional cardiovascular anomalies (6 of 12, p = 0.001). The cardiovascular anomalies encountered were varied. Eight of the 20 patients with such anomalies had only a restrictive ventricular septal defect in addition to the patent ductus arteriosus. Significant anomalies found at catheterization included two thoracic arteriovenous malformations and an isolated right carotid artery draining into the right pulmonary artery by way of a right ductus arteriosus. This study indicates that echocardiography is an effective diagnostic technique in this patient group. A thorough cardiac catheterization with angiography should be performed before implantation of a ductal device.     

Doppler echocardiographic flow characteristics of isolated patent ductus arteriosus: better delineation by Doppler color flow mapping

Eighteen infants and children with isolated ductus arteriosus and various hemodynamic states were examined with the Doppler color flow mapping technique to study the flow patterns of the patent ductus and its adjacent structures. Direct visualization of the ductus was achieved in all patients. All ductal flow was shunting left to right from the descending aorta to the pulmonary artery even in the presence of significant elevation of pulmonary artery pressure. However, transient bidirectional shunting was observed in two patients on serial studies. Disturbed systolic and diastolic flows were demonstrated within the ductus in each case. The blood flows in the main pulmonary artery consisted of three distinguishable areas: 1) a characteristic high velocity turbulent retrograde ductal jet throughout the entire cardiac cycle, located in the anterolateral aspect of the main pulmonary artery; 2) nonspecific low velocity retrograde late systolic and early diastolic flow, located in the posteromedial aspect of the main pulmonary artery; and 3) low velocity forward systolic and diastolic flow, occupying the remaining area of the pulmonary artery. The blood flows in the descending aorta near the ductal orifice consisted of disturbed systolic and diastolic flows in a reversed direction. By providing detailed real time blood flow information with simultaneous imaging of the ductus, Doppler color flow mapping greatly facilitates the detection of a small ductal shunt. This technique also allows detection of a bidirectional or right to left ductal shunt.     

Pulsed Doppler flow characteristics of ductus arteriosus in infants with associated congenital anomalies of the heart or great arteries

Pulsed Doppler echocardiography (PDE) from the suprasternal approach was used to assess flow characteristics of ductus arteriosus (DA) in 145 infants (aged 1 day to 6 months) with major congenital heart disease. Direct ductal Doppler interrogation was possible in 138 patients and serial studies before and after medical treatment were performed in 28 infants. According to pulmonary artery pressure and associated heart lesions, 3 ductal shunting patterns were identified. An isolated left-to-right shunt, observed in isolated DA or in right ventricular outflow tract obstruction, was characterized by a continuous flow with a peak velocity in late systole. An isolated right-to-left shunt, observed in persistent fetal circulation and aortic arch abnormalities, was characterized by a continuous flow with a peak velocity in early systole. In patients with a bidirectional ductal shunt, the right-to-left shunt always occurred in systole and the left-to-right shunt began in late systole and extended into diastole. A systolic right-to-left shunt always corresponded to the presence of significant pulmonary hypertension. Ductal flow changes could be documented after prostaglandin E1 therapy in patients with ductus-dependent heart disease or after tolazoline therapy in patients with persistent fetal circulation. Thus, PDE with direct ductal Doppler interrogation is an important complement to the echocardiographic evaluation of DA. It is a safe noninvasive approach to ductal shunt and permits convenient evaluation of the effects of drugs on pulmonary artery resistance (tolazoline) and ductal patency (prostaglandin E1).     

Pulsed doppler echocardiographic evaluation of the cyanotic newborn: Identification of the pulmonary artery in transposition of the great arteries

During M mode echocardiographic evaluation of cyanotic newborn infants, one may find two ventricles and two great vessels, but not have proof of their identity. Identification of the great vessels is important in evaluation of possible transposition of the great arteries. In a series of 68 cyanotic neonates pulsed Doppler echocardtography was applied to test the hypotheses that (1) a patent ductus arterlosus in present in most cyanotic neonates, (2) the great vessel that receives diastolic ductal flow is the pulmonary artery, and (3) specific noninvasive identification of pulmonary artery will allow diagnosis or exclusion of transposition of the great arteries. On M mode examination, the relations of the great vessels were normal in 43 infants; in all, pulsed Doppler echocardiography detected a patent ductus arteriosus flowing into a normally positioned pulmonary artery. The cyanosis in these 43 patients was later proved to be of pulmonary origin. In eight infants, the relation of the great vessels suggested transposition, and in all eight, Doppler echocardiography detected a patent ductus flowing into the posterior great vessel, proved at angiocardiography to be the transposed pulmonary artery. In 17 patients, the relation of the great vessels was front to back, neither “normal” nor suggestive of classic d transposition. A patent ductus arterlosus, detected with pulsed Doppler echocardiography in all 17, flowed into the anterior great vessel in the 14 normal infants, and flowed into the transposed pulmonary artery in the 3 with proved transposition. It is concluded that ductal patency is prevalent in cyanotic neonates, and that pulsed Doppler echocardiographic detection of ductal flow can define the pulmonary artery; such definition is most helpful in resolving the question of transposition in infants with a relation of the great vessels that is neither normal nor suggestive of transposition.     

Evaluation of pulmonary arterial pressure by Doppler colour flow mapping in patients with a ductus arteriosus.

Blood flow in the pulmonary artery was studied by Doppler colour flow mapping and cardiac catheterisation in 19 patients with a ductus arteriosus and different pulmonary artery pressures. In the four patients with normal pulmonary artery pressures colour Doppler flow mapping showed multicoloured wide and long systolic and diastolic jets in the pulmonary artery. In the 15 patients with raised pulmonary arterial pressure the systolic jets varied from multicoloured to red and were thinner: in patients with considerably raised pulmonary arterial pressure the jets became redder during diastole. The Doppler velocity tracings showed that in patients with normal pulmonary artery pressures the mean peak systolic velocity was higher than the mean end diastolic velocity--so that in all four the ratio of peak systolic velocity to end diastolic velocity was less than 2. The mean peak systolic velocity was much higher than the mean end diastolic velocity in 13 of the 15 patients with raised pulmonary artery pressure; this meant that the ratio of peak systolic velocity to end diastolic velocity was greater than 2 in 10 of 11 patients. The end diastolic velocity was significantly lower in those patients with raised pulmonary artery pressure than in those with normal artery pressure. There was an inverse linear correlation between the mean pulmonary artery pressure and end diastolic ductal jet velocity in 17 of the 19 patients. Colour flow mapping and this quantitative Doppler technique can detect pulmonary artery hypertension in patients with a ductus arteriosus.     

Evaluation of pulmonary arterial pressure by Doppler colour flow mapping in patients with a ductus arteriosus

Blood flow in the pulmonary artery was studied by Doppler colour flow mapping and cardiac catheterisation in 19 patients with a ductus arteriosus and different pulmonary artery pressures. In the four patients with normal pulmonary artery pressures colour Doppler flow mapping showed multicoloured wide and long systolic and diastolic jets in the pulmonary artery. In the 15 patients with raised pulmonary arterial pressure the systolic jets varied from multicoloured to red and were thinner: in patients with considerably raised pulmonary arterial pressure the jets became redder during diastole. The Doppler velocity tracings showed that in patients with normal pulmonary artery pressures the mean peak systolic velocity was higher than the mean end diastolic velocity--so that in all four the ratio of peak systolic velocity to end diastolic velocity was less than 2. The mean peak systolic velocity was much higher than the mean end diastolic velocity in 13 of the 15 patients with raised pulmonary artery pressure; this meant that the ratio of peak systolic velocity to end diastolic velocity was greater than 2 in 10 of 11 patients. The end diastolic velocity was significantly lower in those patients with raised pulmonary artery pressure than in those with normal artery pressure. There was an inverse linear correlation between the mean pulmonary artery pressure and end diastolic ductal jet velocity in 17 of the 19 patients. Colour flow mapping and this quantitative Doppler technique can detect pulmonary artery hypertension in patients with a ductus arteriosus.     

成人动脉导管未闭合并重度肺动脉高压介入治疗及随访研究

目的:探讨成人动脉导管未闭合并重度肺动脉高压封堵治疗可行性及近中远期临床结果。方法:回顾分析2006年6月至2018年6月,首都医科大学附属安贞医院小儿心脏科,34例成人动脉导管未闭合并重度肺动脉高压患者临床资料,患者均行介入治疗,依据治疗前后血流动力学资料及临床资料评估封堵治疗效果,采用心电图及超声心动图进行随访。结果:34例动脉导管未闭合并重度肺动脉压患者进行动脉导管封堵,33例封堵成功,1例封堵失败,封堵成功率为97.1%。介入治疗后患者肺动脉收缩压、肺动脉平均压、肺血管阻力低于治疗前(P<0.05);介入治疗后主动脉收缩压、主动脉平均压高于治疗前(P<0.05);介入治疗前后血氧饱和度比较无统计学差异(P>0.05)。封堵后重复造影无残余分流29例,微量残余分流4例,未见其他并发症发生。患者介入治疗后LAD、LVEDD、PA均低于治疗前(P<0.05);介入治疗后LVEF与术前相比,差异无统计学意义(P>0.05)。结论:介入治疗可安全、有效改善治疗成人动脉导管未闭合并重度肺动脉高压,且近中远期疗效较好,值得广泛应用于临床。     

Percutaneous closure of the small patent ductus arteriosus using occluding spring coils

Objectives. This report summarizes our experience with the use of occluding spring coils to close the small patent ductus arteriosus.Background. Several patent ductus arteriosus occluders (most notably the Rashkind device) have been developed and studied. Occluding spring coils have been used to close abnormal vessels and vascular connections. We previously reported the use of occluding spring coils to close the small patent ductus arteriosus in a small group of patients. This report describes our series of patients having patent ductus arteriosus closure with occluding spring coils.Methods. Between June 1990 and June 1993, 30 patients underwent cardiac catheterization to have patent ductus arteriosus closure by occluding spring coils. Selection criteria were age >6 months and narrowest patent ductus arteriosus internal dimension ⪯3.0 mm by color flow imaging. Definitive selection was based on review of aortograms performed at catheterization. A 5.2F coronary catheter was used to deliver one or two standard occluding spring coils. A loop was delivered in the main pulmonary artery, and the remainder of the coil was delivered across the patent ductus arteriosus and into the aortic diverticulum. Patent ductus arteriosus closure was confirmed by aortography or color flow imaging, or both. Follow-up after coil placement occurred at 6 weeks and 6 months and included two-view chest radiography, echocardiography and color flow imaging.Results. Of the 30 patients, 29 had successful implantation by one (27 patients) or two (2 patients) occluding spring coils. Of these 29 patients, 19 had a clinically apparent and 10 had a silent patent ductus arteriosus. Average ductus minimal internal dimension was 1.7 mm (range 1.0 to 3.0). Complete closure of the ductus was confirmed in 27 patients by aortography or color flow imaging or both (in 24 within 4 h, in 2 after 6 weeks and in 1 after 6 months). Six weeks after implantation, two patients had a tiny residual patent ductus arteriosus noted on color flow imaging. One patient did not have successful implantation. This patient had a 3.2-mm ductus, and two coils migrated to the distal left pulmonary artery and could not be retrieved. There were no deaths or any significant complications noted during early or late follow-up in these patients.Conclusions. Occluding spring coils may have additional application in closing the small patent ductus arteriosus.     

浅低温心脏不停跳体外循环下动脉导管缝闭术

为探讨重症动脉导管未闭（PDA）的手术方法，在浅低温心脏不停跳体外循环下，经主肺动脉切口行动脉导管缝闭术12例，手术效果满意。此祛适用于成人粗大型PDA、PDA并重度肺动脉高压、PDA并感染性心内膜炎、PDA结扎后再通及PDA并存心内畸形。     

Transcatheter coil embolization for patent ductus arteriosus in the elderly: Report of a case and review of the published work

Patent ductus arteriosus is the third most common congenital cardiovascular anomaly, however, it is rarely found in the elderly. We describe a case of patent ductus arteriosus in a 72-year-old woman in whom patent ductus arteriosus was successfully managed by transcatheter coil embolization. The patient had been diagnosed with a heart murmur for the first time 1 year earlier at the age of 71. She was asymptomatic but a continuous murmur was heard. Cardiac catheterization revealed migration of a catheter from the main pulmonary artery into the descending aorta through a patent ductus arteriosus and a significant step-up of oxygen saturation in the main pulmonary artery with a pulmonary-to-systemic flow ratio of 1.68. Aortograms demonstrated a communication between the aorta and the pulmonary artery through a patent ductus arteriosus with a minimal diameter of 3.7 mm. Transcatheter coil embolization of the patent ductus arteriosus was successfully carried out with two 0.052-inch-diameter Gianturco coils. Doppler echocardiographic study confirmed no residual shunt in the main pulmonary artery after the procedure. Non-surgical transcatheter occlusion using coil embolization appears to be an effective and minimally invasive technique for treatment of patent ductus arteriosus in the elderly.     

Color Doppler and transesophageal echocardiography of vascular sling

Summary Three patients with vascular sling were studied by two-dimensional and color Doppler echocardiography and angiocardiography. One case was associated with atrial septal defect and another with tetralogy of Fallot and patent ductus arteriosus. The third case had no associated intracardiac anomalies. Color Doppler flow mapping was performed in all three patients, and transesophageal echocardiography was studied in two patients.Color Doppler echocardiography showed the characteristic features of this congenital anomaly in all three patients, especially in detecting the site of anomalous origin of the left pulmonary artery. A small patent ductus arteriosus was misinterpreted as the normal left pulmonary artery in one patient. Small pulmonary arteries in the patient with tetralogy of Fallot made the diagnosis difficult. Using transesophageal echocardiography, we clearly identified the trachea, esophagus, and abnormal left pulmonary artery.     

Does ductal occlusion with the gianturco coil cause left pulmonary artery and/or descending aorta obstruction?

Thirty-two patients (median age 4.5 years) underwent transcatheter Gianturco coil occlusion of a patent ductus arteriosus. Transthoracic echocardiography was performed the day after coil placement and at intermediate follow-up (median 8.6 months). Echocardiographic results were compared with angiographic and hemodynamic data obtained during catheterization. Two-dimensional (2D) echocardiography performed the day after ductal occlusion displayed evidence of coil protrusion into the left pulmonary artery in 28 of 31 patients (90%) and into the descending aorta in 17 of 29 (59%). However, pulsed Doppler analysis demonstrated normal left pulmonary arterial flow velocities in 28 of 29 patients (97%) and normal descending aortic flow velocities in 26 of 27 (96%). Pulse Doppler results were corroborated by angiographic and hemodynamic catheterization data, which showed no evidence of adjacent vessel obstruction. Peak Doppler velocities among patients with and without 2D echocardiographic left pulmonary artery or descending aorta coil impingement did not differ significantly. The discrepancy between 2D and pulse Doppler findings did not change significantly at intermediate follow-up. Thus, transcatheter occlusion of the patent ductus arteriosus with properly implanted Gianturco coils does not cause significant obstruction to flow in the left pulmonary artery or descending aorta despite frequently misleading 2D echocardiographic images of coil impingement on these vessels.     

Pulsed doppler echocardiographic diagnosis of patent ductus arteriosus: Sensitivity,specificity, limitations,and technical features

To determine the diagnostic features, sensitivity, and specificity of pulsed Doppler echocardiographic (PDE) diagnosis of patent ductus arteriosus (PDA), 110 infants with heart disease were examined by PDE from the precordial and suprastenal notch approaches. On precordial examination, PDA was diagnosed upon recording of diastolic ductal flow into the pulmonary artery. From the suprasternal approach, PDA was suspected upon recording of continuous turbulent flow in the right pulmonary artery. A PDA was proved by invasive means in 45 of 110 cases. Precordial PDE had diagnosed PDA in 43 of 45 cases. In eight of 110, continuous turbulent flow was present in the pulmonary artery from the precordial approach, but no PDA jet was recorded. In two of eight, PDA was present, and in six of eight others systemic-to-pulmonic communications were present. Precordial PDE diagnosis of PDA had a sensitivity of 96%, specificity of 100%, positive predictive index of 100%, and negative predictive index of 97%. From the suprastenal notch approach, PDA was suspected in 51 cases, with six false-positive diagnoses, yielding a sensitivity of 100%, specificity of 91%, positive predictive index of 88%, and negative predictive index of 100%. Since the diastolic ductal jet flowing into the pulmonary artery was specific for PDA in all patients in whom it was recorded from a precordial approach, that approach and diagnostic feature, with sensitivity and positive predictive index of 100%, would seem preferred for PDE diagnosis of PDA. This would be especially important if the PDE diagnosis of PDA were to be used in place of invasive documentation of PDA, and in the differential diagnosis of PDA and other systemic-to-pulmonic communications. The suprastenal approach, while not specific for PDA, may have the advantage of sensitive detection or exclusion of a variety of systemic-to-pulmonic communications.     

High-pressure pulmonary artery aneurysm and unilateral pulmonary artery agenesis in an adult

The presence of a pulmonary artery aneurysm, major aortopulmonary and coronary-pulmonary collateral vessels, and severe pulmonary hypertension in an adult with unilateral pulmonary artery agenesis and previous patent ductus arteriosus ligation is very rare. A 34-year-old man experienced these conditions. When he was 10 years old, catheterization and angiography revealed right pulmonary artery agenesis, dilation of the main pulmonary artery, multiple collateral vessels extending from the aorta to the right pulmonary system, and a patent ductus arteriosus (shunt ratio, 3.57) that was then ligated; the other conditions were not corrected. This adult patient was in New York Heart Association functional class II; mild central cyanosis was detected only during exercise. The right pulmonary arterial system was seen only at the right hilar area via collateral vessels from the subclavian, bronchial, internal mammary, and intercostal arteries. Angiography revealed collateral vessels from the right and circumflex coronary arteries to the right pulmonary system. The right intraparenchymal pulmonary arterial systems were patent but of small diameter (pulmonary artery pressure, 85 mmHg; ratio of peak right-to-left ventricular pressure, 0.94; peak pulmonary pressure unresponsive to 100% oxygen). Pulmonary vascular resistance was not estimated because of the risk of aneurysmal rupture. We concluded that irreversible pulmonary hypertension had developed (delayed by the patent ductus arteriosus ligation in childhood) and that the patient's only chance for survival was heart-lung transplantation. To sustain the patient until surgery, we administered sildenafil. Herein, we describe the vascular conditions that accompany unilateral absence of the pulmonary artery, and therapeutic methods.