Long-term follow-up of subvalvular aortic stenosis in children: a single-centre experience

Objective: The aim of this study is to evaluate clinical and surgical outcomes of children with subaortic stenosis, to determine the risk factors for surgery and reoperation and to compare isolated subaortic stenosis and those concomitant with CHDs. Methods: The study involved 80 children with subaortic stenosis. The patients were first classified as isolated and CHD group, and the isolated group was further classified as membranous/fibromuscular group. The initial, pre-operative, post-operative and the most recent echocardiographic data, demographic properties and follow-up results of the groups were analysed and compared. The correlation of echocardiographic parameters with surgery and reoperation was evaluated. Results: There was a significant male predominance in all groups. The frequency of the membranous type was higher than the fibromuscular type in the whole and the CHD group. The median time to the first operation was 4.6 years. Thirty-five (43.7%) patients underwent surgery, 5 of 35 (14%) patients required reoperation. The rate of surgery was similar between groups, but reoperation was significantly higher in the isolated group. The gradient was the most important factor for surgery and reoperation in both groups. In the isolated group besides gradient, mitral-aortic separation was the only echocardiographic parameter correlated with surgery and reoperation. Conclusion: Reoperation is higher in isolated subaortic stenosis but similar in membranous and fibromuscular types. Early surgery may be beneficial in preventing aortic insufficiency but does not affect the rate of reoperation. Higher initial gradients are associated with adverse outcomes, recurrence and reoperation.

Genetics of canine subvalvular aortic stenosis (SAS)

Subvalvular aortic stenosis (SAS) is one of the most common congenital heart defects of dogs. The disease is characterized by obstruction of the left ventricular outflow tract, resulting in pressure overload on the left ventricle. The etiology of obstruction is a fibromuscular nodule, ridge, or ring of tissue that increases aortic outflow tract velocity. This review is focused on the prevalence, inheritance pattern, and current genetic insights of canine SAS. The prevalence of this disease was reported at 4.7 % in a large veterinary referral hospital. The mode of inheritance for this disease has also been described in breeds with a high disease prevalence such as the Bullmastiff, Bouvier des Flandres, Dogue de Bordeaux, Golden Retriever, Newfoundland, and Rottweiler. Genetic investigations seeking to identify causative mutations for SAS are lacking with only a single published variant associated with SAS in Newfoundlands.

Aortocaval compression resulting in sudden loss of consciousness and severe bradycardia and hypotension during cesarean section in a patient with subvalvular aortic stenosis

Background Maternal cardiac arrest during cesarean section (CS) is an extremely rare but devastating complication. Preventing emergency events from developing into maternal cardiac arrest is one of the most challenging clinical scenarios. Case presentation A 35-year-old pregnant woman with subvalvular aortic stenosis who was scheduled for elective CS under epidural anesthesia, and experienced devastating supine hypotensive syndrome, but was successfully resuscitated after delivery. Conclusions The performance of tilt position strictly or high-quality continue manual left uterine displacement (LUD) should be performed until the fetus is delivered, otherwise timely delivery of the fetus may be the best way to optimize the deadly condition.

Aortocaval compression resulting in sudden loss of consciousness and severe bradycardia and hypotension during cesarean section in a patient with subvalvular aortic stenosis

Background: Maternal cardiac arrest during cesarean section (CS) is an extremely rare but devastating complication. Preventing emergency events from developing into maternal cardiac arrest is one of the most challenging clinical scenarios. Case presentation: A 35-year-old pregnant woman with subvalvular aortic stenosis (SAS) who was scheduled for elective CS under epidural anesthesia, and experienced devastating supine hypotensive syndrome, but was successfully resuscitated after delivery. Conclusions: The performance of tilt position strictly or high-quality continue manual left uterine displacement (LUD) should be performed until the fetus is delivered, otherwise timely delivery of the fetus may be the best way to optimize the deadly condition. Keywords: Subvalvular aortic stenosis, Pregnancy, Cesarean section, Hypotension.