Main Pulmonary Artery Stenosis Research Articles

The Role of Cardiac MRI and Late Gadolinium Enhancement Grading Protocol in Evaluation of the Right Ventricle in Patients with Repaired Fallot Tetralogy

Abstract Background Tetralogy of Fallot represents 7–10% of congenital heart diseases occurring in 0.5/1000 live births and is the second most common form of complex congenital heart diseases. The four elements of Tetralogy of Fallot: (a) sub-pulmonary obstruction resulting in (b) right ventricle hypertrophy, and (c) malalignment ventricular septal defect resulting in (d) apparent overriding of the aorta over both ventricles. Primary cardiac repair for Fallot Tetralogy patients includes right ventricular out flow tract widening interventions and ventricular septal defect closure. For such patients right ventricular assessment in the postoperative period is essential in aiding further management planning. The purpose of this study is to emphasize the role of cardiac MRI in functional and structural assessment of the right ventricle in Fallot tetralogy patients after surgical management. Results The current study included 30 Fallot Tetralogy patients underwent cardiac MRI after surgical management. The majority of patients 26 out of 30 (86.6%) showed right ventricular dilatation. Four patients had right atrial dilatation. Less than one-third of patients 8 out of 30 (26.6%) had right ventricular systolic dysfunction. The majority of patients 29 out of 30 (96.6%) had main pulmonary artery regurgitation. More than half of the patients 18 out of 30 (60%) had main pulmonary artery stenosis. The majority of patients 25 out of 30 (83.3%) had right ventricular outflow tract late gadolinium enhancement and 18 patients (60%) had base of interventricular septal enhancement. Conclusions MRI is an extremely useful imaging method for functional and structural assessment of the right ventricle after surgical repair of Fallot tetralogy patients with absence of ionizing radiation.

Long-term evolution of aortic arch interruption repair with pulmonary artery autograft

Surgical correction of the aortic arch interruption (IAA) is regularly complicated by anastomosis stenosis or the long-term occurrence of arterial hypertension. In order to prevent these complications, a new surgical technique has been developed in our center consisting of the interposition of a segment of the main pulmonary artery to enlarge the aortic anastomosis. The purpose of this study was to assess the 10 years outcome of this intervention. Four children undergoing this surgery with a follow-up over 10 years were retrospectively included. Data collected focused on the last measure of blood pressure (BP), the last echocardiographic evaluation, and the aortic arch dimension on the last CT. The whole patients had IAA type B and 22q11 microdeletion. The median follow-up duration was 13.9 years (range: 9.3 to 15.3). None of them had a new surgery of the aortic arch, but one need enlargement of ascending aorta. Only one patient developed a mild restenosis at the isthmic insertion of the pulmonary autograft [Z score −2.7 at CT ( Fig. 1 C)], responsible of mild arterial hypertension (systolic BP 75th percentile, diastolic BP 98th percentile), and a left ventricle hypertrophy (Z score IVSd 2.5, Z Score LVPWd 2.1). The three others patients displayed normal BP, no left ventricular hypertrophy, no significant aortic arch obstruction on Doppler evaluation and minimum Z score of aortic arch at CT from −1.8 to −0.4 ( Fig. 1 A, B, D). None of them did experience a main pulmonary artery stenosis. Reconstruction of the aortic arch with a pulmonary artery autograft for the correction of IAA provides a good long-term result.

Echocardiography and MRI parameters associated with exercise capacity in patients after the arterial switch operation

BackgroundThe arterial switch operation (ASO) for transposition of the great arteries has excellent survival, but a substantial number of patients suffer from a reduced exercise capacity. The goal of this study was to identify imaging parameters associated with a reduced exercise capacity in patients after ASO. MethodsA retrospective analysis was performed of ASO patients who underwent cardiopulmonary exercise testing (CPET) between 2007 and 2017. Reduced exercise performance was defined as a reduced workload peak (Wpeak) with Z-score <−2 or a peak oxygen uptake indexed for weight (VO2peak/kg) with Z-score <−2. Data on echocardiography and cardiac magnetic resonance performed within 1 year of the CPET were collected for comparison. ResultsA total of 81 ASO patients (age 17±7 years) were included. Reduced exercise performance was found in 22 patients (27%) as expressed by either a reduced Wpeak and/or a reduced VO2peak/kg. Main pulmonary artery gradient and tricuspid regurgitation gradient by echocardiography were found to be associated with reduced Wpeak (p=0.031; p=0.020, respectively). The main pulmonary artery gradient and tricuspid regurgitation gradient by echocardiography were found to be associated with reduced VO2peak/kg (p=0.009; p=0.019, respectively). No left ventricular parameters were found to be associated with abnormal exercise performance. ConclusionThis study demonstrates that ASO patients frequently experience reduced exercise capacity. Echocardiographic evidence of main pulmonary artery stenosis and increased right ventricular pressure were associated with reduced exercise capacity, and are therefore key to monitor during serial follow-up of ASO patients.

P2742Right ventricular stroke volume during dobutamine stress magnetic resonance compared to lung perfusion and peak oxygen uptake after arterial switch operation for transposition of the great arteries

Abstract Objectives Abnormal pulmonary perfusion due to stenosis of the central pulmonary arteries is common after neonatal arterial switch operation (ASO) for transposition of the great arteries (TGA). We conducted a monocentric prospective study in young adults after neonatal ASO for TGA to evaluate the effects of abnormal pulmonary perfusion on the increase of the right ventricular stroke volume (RVSV) during dobutamine stress magnetic resonance (DSMR) and on cardiopulmonary exercise capacity. Methods 68 unselected patients (age 18–29 years) underwent CMR at rest and under dobutamine stress (10 to 40 μg/kg/min). RVSV, pulmonary blood flow distribution (PBFD) and peak flow velocity were derived from phase contrast mapping in the main, right and left pulmonary artery (PA) at rest and each stress level. A cardiopulmonary exercise test (CPET) was performed at the same day. All patients reached maximal exercise effort according to heart rate and respiratory exchange rate. Results PBFD at rest: 9/68 patients (13%, ASO-S) had abnormal pulmonary perfusion at rest, defined as PBFD &gt;2:1 (right/left or left/right) and/or relevant stenosis of the main PA (Vmax &gt;2.5 m/s). 59/68 patients (87%, ASO-N) had normal pulmonary perfusion. PBFD under DSMR: (1) In the whole patient group, there was no increase of PBFD under stress compared to PBFD at rest. On an individual patient level, no relevant worsening of abnormal PBFD was found. (2) Under low dose dobutamine, ASO-S had a significantly lower RVSV-increase (RVSVstress/RVSVrest) compared to ASO-N (see figure). However, under high dose dobutamine, this effect was no longer significant (see figure). (3) The RVSV-increase under low and high dose dobutamine did not correlate with peak oxygen uptake during CPET, neither in the total group nor in the subgroups (see table). Peak oxygen uptake was not significantly different between ASO-N and ASO-S (p=0,72). RVSV-increase compared to CPET peak VO2% ASO-total ASO-S ASO-N RVSV-increase/peak VO2% RVSV-increase/peak VO2% RVSV-increase/peak VO2% low dose dobu high dose dobu low dose dobu high dose dobu low dose dobu high dose dobu Pearson correlation coefficient −0.02 −0.05 0.01 −0.22 −0.05 −0.04 p-value 0.90 0.71 0.98 0.56 0.71 0.78 Figure 1 Conclusion (1) Patients with relevant stenosis of main PA and/or abnormal peripheral blood flow distribution (ASO-S) exhibit a reduced RVSV-increase under low dose dobutamine compared to patients without stenosis (ASO-N). This effect was not present under high dose dobutamine stress. (2) These findings did not correlate with peak oxygen uptake during CPET, an objective parameter of cardiopulmonary exercise capacity. (3) Therefore, a conservative proceeding rather than surgery or catheter intervention should be considered, especially in asymptomatic adult patients. Acknowledgement/Funding Supported by Kinderherzen, Fördergemeinschaft Deutsche Kinderherzzentren e.V.

Surgical outcome of isolated congenital supravalvular pulmonary stenosis: a case series.

BackgroundSupravalvular stenosis of main pulmonary artery is a rare anomaly characterized by the presence of constriction band just above the pulmonary valve. It is mostly acquired after intervention on the pulmonary trunk or less commonly is congenital in origin associated with complex congenital cardiac malformations and very rarely can present as an isolated native congenital supravalvular pulmonary stenosis (SPS).Case summaryWe present a series of four cases of isolated congenital SPS who underwent surgical correction at our tertiary care institute over 8 years. Mean age of the patients was 2.25 ± 0.96 years with all of them being males. Mean peak systolic gradient across the stenosis was 82 ± 21.48 mmHg ranging from 60 mmHg to 110 mmHg. There was no early and medium-term mortality with 100% survival at mean follow-up of 31 months (range 7–85 months).DiscussionSurgical correction of congenital SPS carries excellent early and mid-term results with almost no mortality and very low risk of re-intervention for restenosis.

Pulmonary artery sarcoma manifesting as a main pulmonary artery stenosis diagnosed by 18F-FDG PET/CT

Pulmonary artery sarcoma manifesting as a main pulmonary artery stenosis diagnosed by 18F-FDG PET/CT

Surgical Repair of Supravalvular Aortic Stenosis in Children With Williams Syndrome: A 30-Year Experience

Williams syndrome is an uncommon genetic disorder associated with supravalvular aortic stenosis (SVAS) in childhood. We reviewed outcomes of children with Williams syndrome who underwent repair of SVAS during a 30-year period at a single institution. Between 1982 and 2012, 28 patients with Williams syndrome were operated on for SVAS. Mean age at operation was 5.2 years (range, 3 months to 13years), and mean weight at operation was 18.6 kg (range, 4.1 to 72.4 kg). Associated cardiac lesions in 11patients (39.3%) were repaired at the time of the SVAS repair. The most common associated cardiac lesion was main pulmonary artery stenosis (8 of 28 [28%]). A 3-patch repair was performed in 10 patients, a Doty repair in 17, and a McGoon repair in 1 (3.6%). There were no early deaths. Follow-up was 96% complete (27 of 28). Overall mean follow-up was 11.2 years (range, 1 month to 27.3 years). Mean follow-up was 5 years (range, 1 month to 14.3 years) for the 3-patch repair patients and 14.7 years (range, 6 weeks to 27 years) for the Doty repair patients. Of the 17 Doty patients, there were 4(24%) late deaths, occurring at 6 weeks, 3.5 years, 4years, and 16 years after the initial operation. There were no late deaths in the 3-patch repair patients. Overall survival was 86% at 5, 10, and 15 years after repair. Survival was 82% at 5, 10 and 15 years for the Doty repair patients. Overall, 6of 27 patients (22%) patients required late reoperation at a mean of 11.2 years (range, 3.6 to 23 years). No 3-patch repair patients required reoperation. Overall freedom from reoperation was 91% at 5 years and 73% at 10 and 15years. Freedom from reoperation for the Doty repair patients was 93% at 5 years and 71% at 10 and 15 years. Surgical repair of SVAS in children Williams syndrome has excellent early results. However, significant late mortality and morbidity warrants close follow-up.

Giant pulmonary artery aneurysm associated with mild congenital pulmonary stenosis

Pulmoner arter anevrizmasi oldukca nadir gorulen bir durumdur. Konjenital valvuler pulmoner darlikta poststenotik pulmoner arter dilatasyon ve anevrizmasi gelisebilir. Sirt agrisi sikâyeti ile gittikleri doktor tarafindan kalpte ufurum olmasi nedeni ile klinigimize basvuran; pulmoner balon valvuloplasti uyguladigimiz, hafif konjenital pulmoner darlik ve ana pulmoner arterde anevrizmatik genisleme ( pulmoner arter capi; 5.6cm) saptadigimiz 11 yasindaki olguyu sunduk. Dogumsal valvuler pulmoner darliga seconder poststenotik anevrizmal dilatasyon nadir bir klinik tablodur. Pulmoner hipertansiyon ve soldan-saga santli konjenital kalp hastaligi yoksa balon valvuloplasti guvenli ve etkili bir yontemdir.

Extra-anatomic pulmonary artery bypass for main pulmonary artery stenosis caused by neoplasm

Extra-anatomic pulmonary artery bypass for main pulmonary artery stenosis caused by neoplasm

Late Complications After Takeuchi Repair of Anomalous Left Coronary Artery From the Pulmonary Artery: Case Series and Review of Literature

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital heart lesion that if left untreated, results in high mortality. Surgical treatment options include reimplantation of the anomalous coronary ostia, use of extracardiac arterial blood supply, or the Takeuchi procedure. The Takeuchi procedure involves creation of an aortopulmonary window and an intrapulmonary tunnel that baffles the aorta to the ostium of the anomalous left coronary artery. The incidence of late complications following the Takeuchi repair is unknown. The goal of our study was to determine the long-term outcome after palliation of ALCAPA using the Takeuchi Procedure. A total of 9 patients with a history of ALCAPA palliated with the Takeuchi procedure were identified from our surgical database. Chart review was performed. The mean age at time of Takeuchi procedure was 49.6 months (range 5 weeks-14.6 years). There was one late death, of unknown cause. Of the remaining 8 patients, the mean length of follow-up after surgery was 15.9 years (13.5-19.7 years). All 8 survivors had some degree of main pulmonary artery stenosis in the area of the intrapulmonary baffle, with moderate stenosis in 2 and severe stenosis in 1. Three late survivors (38 %) had a baffle leak. Two patients (25 %) had decreased left ventricular systolic function and 3 (38 %) had developed at least moderate mitral valve regurgitation. Three of the 8 late survivors (38 %) required a reoperation for repair of mitral valve regurgitation, baffle leak, and main pulmonary artery (MPA) stenosis. Review of literature demonstrated similar complication rates and need for reoperation following the Takeuchi procedure. Compared with patients after direct reimplantation for ALCAPA at our institution, there was no significant difference in late survival or freedom from reoperation. The Takeuchi procedure is a method to establish a two-coronary repair for ALCAPA. Late complications are common, necessitating lifelong care in a center experienced with caring for adults with congenital heart disease.

Effect of Abnormal Pulmonary Flow Distribution on Ventilatory Efficiency and Exercise Capacity After Arterial Switch Operation for Transposition of Great Arteries

Patients with anatomic repair of transposition of the great arteries (TGA) can present with branch pulmonary artery (PA) stenosis; however, its relation to an abnormal cardiopulmonary response to exercise is unknown. We investigated the relation between the PA anatomy and pulmonary blood flow (PBF) distribution and the cardiopulmonary response to exercise in patients with anatomic repair of TGA. We used cardiopulmonary exercise testing and magnetic resonance imaging to study 55 consecutive patients (62% male; age 14.4 ± 2.3 years) who had undergone neonatal anatomic repair of TGA. The peak oxygen uptake and slope of carbon dioxide elimination/minute ventilation was 79 ± 15% of predicted and 29.8 ± 3.8, respectively. Abnormal peak oxygen uptake (R = 0.363, p = 0.0082) and slope of carbon dioxide elimination/minute ventilation (R = 0.612, p <0.0001) values were associated with an abnormal right/left PBF distribution. However, although an increased ventilatory response to exercise appeared to be primarily related to an abnormal right/left PBF distribution, exercise capacity appeared to be related to the extent of the proximal PA branches and main PA stenosis (R = 0.476, p = 0.0004), suggesting that mechanical obstruction to PBF during exercise could be the main mechanism causing an abnormal exercise capacity. In conclusion, an abnormal PBF distribution related to branch PA stenosis or hypoplasia was associated with a reduced exercise capacity and increased ventilatory drive during exercise in patients with anatomic repair of TGA. Cardiopulmonary exercise test data can complement the anatomic and magnetic resonance imaging data in selecting those lesions that are functionally important.

Validation of echocardiographic indices of right ventricular afterload: an experimental, open pericardium pig model

Pulmonary vascular resistance (PVR) has been used to assess right ventricular afterload; however, this is considered meaningless due to several physiologic shortcomings. Echocardiography has often been used to assess right ventricular (RV) afterload, but this has never been validated as an index of RV afterload. The purpose of this study is to evaluate echocardiographic indices of RV afterload in an experimental, open-pericardium pig model with induced, variable main pulmonary artery stenosis.

Endovascular stenting for treatment of an adult patient with pulmonary artery stenosis with 1-year follow-up

This report describes the occurrence of symptomatic proximal left main pulmonary artery stenosis in a 58-yr-old man that was successfully treated with endovascular stenting with 1-yr follow-up. The technique and pitfalls of this procedure are described. Endovascular stenting provided a well-tolerated, nonsurgical approach to alleviating isolated pulmonary artery stenosis in this patient.

Isolated Pulmonary Artery Stenosis: Four-Year Follow-Up: Case Report

The authors present a four-year follow-up of a patient with a single isolated right main pulmonary artery stenosis without an associated cardiac anomaly. This is an extremely uncommon lesion thought to be congenital. This case illustrates the stability of isolated lesions of the pulmonary vasculature without associated cardiac defects.

Results of total correction of tetralogy of Fallot with complete atrioventricular canal

Four patients with tetralogy of Fallot (TF) and complete atrioventricular canal (CAVC) underwent successful intracardiac repair. All patients had undergone preliminary palliative shunts. Associated cardiovascular lesions included muscular ventricular septal defect (VSD) and left superior vena cava (one patient), bilateral main pulmonary artery stenosis (one patient), and right aortic arch (two patients). The diagnosis was suspected clinically by electrocardiographic evidence of right ventricular hypertrophy and left anterior hemiblock, by echocardiographic findings suggestive of CAVC with aortic dextroposition, and by the association with trisomy 21. The diagnosis was confirmed by cardiac catheterization and cineangiography. Total correction consisted of closure of the VSD and atrial septal defect (ASD), reconstruction of the atrioventricular valves, and relief of the right ventricular outflow tract obstruction (RVOTO). There were no early or late postoperative deaths. Surgically induced complete heart block did not occur. One patient underwent successful reoperation for residual VSD and right ventricular outflow aneurysm. Late hemodynamic evaluation revealed good results in all patients. We recommend a staged treatment plan consisting of preliminary systemic--pulmonary artery shunting for symptomatic children under 4 to 5 years of age and total correction for older children. With proper preoperative diagnosis and accurate intracardiac repair, good results may be obtained after total correction of TF and CAVC.

Tetralogy of Fallot. Angiocardiographic diagnosis compared with surgical findings.

SummaryWith Value of Angiocardiography in Tetralogy of FallotInfundibular StenosisThe recognition of an organic pulmonary infundibular stenosis is important. It occurred in 76% of the cases. I t is usually at the crista, and in the sagittal plane, but tends to be in the coronal plane, and more horizontally if very low. It may be “band‐like”, but more often it appears as a “tight” constriction.In fundibular ChamberThe next most favourable group for surgery are those with a high or intermediate pulmonary infundibular stenosis and a small chamber (Group 2).The most difficult group surgically is the group with a high pulmonary infundibular stenosis and no chamber (Group 3), A larger proportion of these cases have pulmonary valve stenosis in addition to pulmonary infundibular stenosis, and many also have hypoplasia of the outflow tract from the valve ring onwards. (Sec paragraph below.)Pulmonary Valve Stenosis (36 cases in all)This occurred in about half of the cases with pulmonary infundibular stenosis, i.e., 19 cases, or and incidence of about 31%. It also occurred isolated in the groups with muscular pulmonary infundibular stenosis (Group 4) and double outlet right ventricle (Group 5), 28% Total incidence, about 60%.In the former group, a “muscular” type of infundibular stenosis was recognized which the surgeon described as “not a true organic pulmonary infundibular stenosis”. This is when there is no definite evidence of a localized constriction, there is a very labile outflow tract with more variation in size than in the groups above, or a very trabeculated outflow tract. In almost all these case the muscular hypertrophy in the outflow tract and in the right ventricle was found to be secondary to pulmonary valve stenosis, with in many cases hypoplasia of the main pulmonary artery and of the pulmonary artery branches also. Thus this group can be considered as pure pulmonary valve stenosis–20%Hypoplasia or Coarctation of the Main Pulmonary Artery and Pulmonary Artery Branches Distal to the Valve (25%)It is very important to recognize such cases, as they are less favourable surgically and a patch may be required. Supra‐valvular narrowing is the commonest type of main pulmonary artery stenosis, But coarctation of the branches is common, often involving both branches, and often not recognizable without angiocardiography. In many of these cases the surgeon has had to place a patch in the outflow tract in addition to performing a pulmonary valvotomy. The risk of surgery is thus much greater in this group, particularly in cases under the age of four years.Double outlet Right Ventricle — with Absent Crista (8%)In many cases a fairly certain diagnosis of this can be made, and if not the surgeon should be warned of this possibility. These cases had muscular hypertrophy of the infundibulum and right ventricle and all had pulmonary valvestenosis also.Ventricular Septal DefectThis was usually infra‐cristal, or Type 2. Supra‐cristal defects should be watched for. However, the left anterior oblique projection is preferable for the anatomy of the septa1 defect.Overriding or Dextroposition of AortsAgain this is best demonstrated in the left anterior oblique projection. A record of the amount of dextroposition was made in about half the cases, but was abandoned later as it was found that the correlation between this and the degree o f cyanosis, i.e. severity of the condition and the anatomy of the infundibular stenosis was very poor.However, extreme dextroposition should be noted as it may approximate to or resemble a double outlet right ventricle.Associated AnomaliesThese should also be watched for, e.g. anomalous coronary artery (Case 13, Figure 6).In many of these cases the recognition of an infundibular chamber above the constriction is a valuable guide to the presence of an organic pulmonary infundibular stenosis. A chamber was present in 29% of the cases if a low pulmonary infundibular stenosis can if a low pulmonary infundibular stenosis can be recognized, and especially if this chamber can be seen, as in group 1 and group 2, it is very likely that there will be no valvular stenosis or hypoplasia of the out flow tract beyond If the chamber is large, as in Group 1, there is never a distal obstruction beyond this, i.e. no valve stenosis, and the surgeon does not need to consider the possibility of having to insert a patch. In all cases where there is a chamber the anatomy is favourable, and the larger the chamber the smaller the risk. In all our patients who have had a complete repair of the Fallot's tetralogy and pulmonary valvular stenosis, the long‐term results have been satisfactory.

The course of artificially produced main pulmonary artery stenosis in the dog

The course of artificially produced main pulmonary artery stenosis in the dog

Artificially produced pulmonary artery stenosis in the dog

The genesis of the obstructive infundibular hypertrophy which is seen in association with pulmonary valvar stenosis, especially beyond infancy, has been explained upon an acquired basis (compensatory) but this has not been substantiated. Also, there are conflicting opinions about the necessity for resecting the infundibular muscle when the pulmonary valve is lysed. Experiments were devised using puppies in which the main pulmonary artery was banded. There was progressive increase in the right ventricular pressure, marked infundibular hypertrophy developed, as demonstrated by angiocardiography, and the cardiac output decreased. After 14 to 22 months, the pulmonary stenosis was relieved surgically and the infundibular region was not resected. After 2 to 10 months there was still significant infundibular hypertrophy. The right ventricular pressure returned to normal levels and the cardiac output increased. These experiments suggest that infundibular hypertrophy is an acquired complication of main pulmonary artery stenosis in the dog. In the human, valvotomy in infancy may prevent the development of infundibular hypertrophy. Valvotomy alone may be all that is needed, when there is an immediate drop in the right ventricular pressure, below 100 mm. Hg, at time of operation.