Mid-aortic syndrome in two preterm infants

Abstract

We report mid-aortic syndrome (MAC) in two preterm infants. Both infants developed malignant hypertension refractory to medical therapy and died early in infancy. Thus far, this account is of the two youngest patients with MAC. Journal of Perinatology (2012) 32, 390-392; doi:10.1038/jp.2011 Keywords: preterm; mid-aortic syndrome; hypertension Introduction Mid-aortic syndrome (MAS) is a rare but important cause of renovascular hypertension in children and young adults. 1 It is characterized by segmental narrowing of the distal thoracic or abdominal aorta and stenosis of one or both renal arteries and major splanchnic vessels. 1-6 Diagnosis of MAS in premature infants is rare; this report describes the presentation and clinical course in two such patients. Case Patient 1The patient was a male infant born to a 20-year-old G 2 P 1 woman. Fetal Echocardiogram (ECHO) at 27 weeks detected premature closure of the ductus arteriosus, diminished right ventricular (RV) systolic function and RV hypertrophy. The patient was delivered by cesarean section at 28 weeks for worsening RV function. He required intubation, chest compressions and intratracheal epinephrine for apnea and bradycardia at 2 min of life. APGAR scores were 7, 1 and 7, at 1, 5 and 10 min, respectively. Birth weight was 1605 grams. Heart rate: 180 beats per min, respiratory rate: 52 breaths per min, preductal and postductal saturations: above 95% on FiO 2 of 0.3 and conventional mechanical ventilator support. There was a significant blood pressure (BP) difference between the upper and lower extremities: right arm 78/43 mm Hg, left arm 52/39 mm Hg, right leg 37/27 mm Hg, left leg BP could not be obtained. He had no appreciable dysmorphic features. Breath sounds were normal; murmurs were absent. There was no hepatosplenomegaly or abdominal bruit. The right brachial pulse was well felt, but the left brachial and femoral pulses were diminished.Postnatal ECHO demonstrated a widely patent right aortic arch, a small ductus arteriosus and severely diminished RV systolic function. A computed tomography (CT) angiogram identified narrowing of the abdominal aorta just below the level of the origins of the celiac and superior mesenteric arteries that measured 1.4  1 mm at its narrowest infrarenal portion (Figure 1). The abdominal aorta then increased in diameter (2.7 mm  2.4 mm) just before the iliac bifurcation. Enlarged paraspinal/lumbar collaterals fed into the abdominal aorta at multiple levels. The renal arteries were diminutive without collateral supply to the kidneys. Renal ultrasound demonstrated normal sized kidneys. Serum creatinine levels peaked on the third day of life at 1.3 mg dl À1 and normalized to 0.6 mg dl À1 by the fourth week of life. Williams and 22q11 deletion syndrome were excluded by genetic testing.He remained on ventilator support for 5 days and was extubated to continuous positive airway pressure. He received inhaled nitric oxide and Dopamine for 3 days. The patient's course was marked by severe systemic hypertension with right arm systolic BP...

Konjenital midaortik sendromlu bir bebek

“…She had an improvement in blood pressure, however hypertension persisted. In uncontrolled hypertension, endovascular percutaneous transluminal angioplasty with or without stents or balloon dilation have been performed in children and adolescents, however symptomatic MAS in newborn period is almost fatal 3,[11][12][13][14] . Balloon dilation and stenting are effective for short-segment lesions but do not yield favorable results in patients with long-segment stenosis 15. As the present patient was only 2600 g, we wanted to do medical treatment allowing her to grow until surgery or stent placement.…”

“…Unfortunately she died due to heart failure. To our knowledge there are only 9 newborn cases in the literature [10][11][12][13][14]16,17 . Five of 9 babies died secondary to intraventricular hemorrhage or cardiac failure 10,[12][13][14] .…”

Middle aortic syndrome in children and adolescents

“…Premature mortality remains high in patients who present in the neonatal period with hypertension refractory to medical therapy, as their small size makes endovascular procedures challenging and prohibits surgical management [21,24,38,39]. In older children, however, morbidity and mortality rates are reported to be improving.…”

Diagnosis and Management of Genetic Causes of Middle Aortic Syndrome in Children: A Comprehensive Literature Review

“…Presentation in infancy has also been reported and has a poor prognosis, especially in preterm infants. 28 …”