Patients’ treatment details and follow-up
Patient 1. A 3-day-old boy presented with hypertension. His echocardiogram demonstrated distal thoracic aorta coarctation. Angiography and CTA confirmed MAS diagnosis Fig. 1A-C). Owing to his young age, it was decided to start medical treatment only. Nevertheless, due to persistent HT despite optimized medical treatment, at the age of 6.9 years, he underwent a PTA of the descending thoracic aorta where 3 stents were implanted in a telescopic fashion (Fig. 2A-B, videos 1–4). His subsequent CTA revealed a reduction of the previously demonstrated collateral formation. He is currently on decreasing doses of his three anti-hypertensive agents with acceptable BP measurements 8 months after his last procedure.
Patient 2. An 11-day-old male new-born was referred for evaluation of a heart murmur. His echocardiogram revealed a thoracic aortic coarctation. A PTA of this region was subsequently performed with good results. At 2 months of age, he presented at the emergency department with shortness of breath and feeding difficulties. His repeated echocardiography demonstrated recoarctation of the aorta at the isthmus level, undergoinga second PTA, without significant improvement. Hence, surgical intervention with extended coartectomy with term-terminal anastomosis was performed 10 days later. Despite initial success, he required three further PTAs of the thoracic aorta due to recoarctation suspected by echocardiography (Fig. 3A-C). Additionally, a stent was placed at the level of the proximal descending aorta during the latter procedure. At the age of 1.7 years, an echocardiogram revealedstent stenosis. Therefore, he underwent PTA of the implanted stentanda stent within a stent implantation. He was diagnosed with MAS after a CTA was performed at 2.3 years (Table 2). Owing to his young age and the high complexity of his arterial disease, surgical intervention was excluded at that time. At the age of 7.0 and 8.5 years, he underwent two further PTAs for in-stent restenosis. He is currently on 3 antihypertensive agents with stage 1 HT, 1.3 years after his last procedure.
Patient 3. She was prenatally diagnosed with tricuspid valve dysplasia with severe tricuspid valve regurgitation. Additionally, her fetal cerebral magnetic resonance imaging showed subependymal cystsat thecaudothalamic groove, right ventriculomegaly and suspected bilateral germinal matrix haemorrhage. At 10 days of age, whilst admitted at the neonatal intensive care unit, she presented with significant BP discrepancy between upper and lower extremities. Thus, a CTA was performed confirming MAS diagnosis (Fig. 3D). As aforementioned, this patient aditionally had right aortic arch, diffuse hypoplastic pulmonary arteries, and severe obstruction of the origin of the left carotid artery with anhypoplastic vessel. She underwent a catheter angiography at 20 days of agewith aortoiliac balloon dilatation. Following this, she achieved acceptable BP control. Surgical intervention was excluded for the high complexity and widespread of the arterial and venous disease. She presented clinical deterioration with heart failure despite optimisation of medical therapy and she died at 36 days of age.
Patient 4. A 2.9 year-old boy was referred for HT. CTA confirmed MAS diagnosis. He has not required any interventions. Nevertheless, his BP recently rose to stage 2 HT and he is currently on increasing doses of his antihypertensive treatment.
Patient 5. A 4.9 year-old girl was referred for incidental HT. Her CTA was in keeping with MAS diagnosis.For uncontrolled HT and severe bilateral RAS, she underwent a PTA of the abdominal aorta and a bioresorbable stent was placed in each renal arteryat the age of 5.3 years. One month later, due to refractory HT, she underwent an unsuccessful PTA attempt of the left renal artery. As no hypoperfusion renal areas were observed during the procedure, it was decided not to perform further attempts. At the age of 8.5 years, she continued to be hypertensive despite optimized medical treatment. Furthermore, she was symptomatic with headache and dyspnea on exertion. She subsequently underwent another PTA of the right renal artery with insertion of a bioabsorbable stent. Although her BP improved, she remained hypertensive. At 10.9 years, her CTA showed a re-stenosis of the right renal artery. Hence, she underwent a PTA of this vessel and a stent was placedat thecoeliac artery, at the abdominal aorta and at the right renal artery. This latter procedure ameliorated her symptoms but had minimal impact on her BP. At the age of 12.4 years, she continued to be hypertensive and a slight increase of her LVH was observed. A renal ultrasound was therefore performed and revealed diminished arterial perfusion of the right kidney. Thus, she underwent another PTA of the right renal artery. She is currently asymptomatic with good BP control with three antihypertensive medications after 6.5 years follow-up.
Patient 6. A 14.0 year-old boy presented with incidental HT. His MRA confirmed MAS diagnosis. At that time, his parents refused aortic surgery due to potential complications. After three years of medical treatment, he had uncontrolled BP and developed claudication. For these reasons, at the age of 17.8 years, he underwent a PTA of the left renal artery with stent implantation with significant improvement of his BP. Two months later, he underwent stent dilatation and a PTA of the abdominal aorta, where another stent was inserted. His BP and symptoms initially improved although he is currently hypertensive (stage 2 HT) in the context of poor medication adherence.
Patient 7. A 4.1 year-old boy was referred for incidental HT. The CTA performed was in keeping with MAS diagnosis and he was subsequently started on medical treatment with initial acceptable BP control. At the age of 6.6 years, for persistent HT and in view of progressive left renal artery stenosis and reduced left renal volume on his CTA (Fig. 3E-F), he underwent an unsuccessful attempt at the left renal artery dilatation. At the age of 6.8 years, he had another unsuccessful attempt. It was then decided to continue on medical therapy and not to perform further attempts. He is currently asymptomatic with stage 1 HT on three antihypertensive agents after 6.7 years follow-up.
Patient 8. An 8-month-old girl was admitted to PICU as she presented with heart failure symptoms. During her admission, she was found to be hypertensiveand an angiography confirmed MAS diagnosis. To resolve the right renal artery stenosis, she underwent right a aortorenal bypass using femoral artery homograft with initial good result. At the age of 1.0 year, due to partial occlusion of the right renal artery observed on her follow-up CTA, she required a PTA of this artery with a stent placement. A repeated CTA at 1.5 years showed severe left renal artery stenosis for which she underwent a left spleno-renal bypass. Nevertheless, there was a left renal function loss right after the latter surgery. Her follow-up CTAs demonstrated progressive in-stent stenosis, requiringa PTA of the right renal arterystentat 3.3 years of age. She is currently with good BP control on monotherapy after 10.1 years of follow-up.