Maternal hemodynamic adaptation in the first weeks of pregnancy is defective in IUGR pregnancies, presumably associated with a concomitant inadequacy of the vascular filling state.
The Ross procedure for congenital aortic valve disease in children and young adults offers excellent hemodynamics, with the added advantage of real potential for growth. It should be considered the treatment of choice in this age group.
Fetal growth restriction is preceded by defective volume adaptation very early in pregnancy. It appears that the maternal compensation mechanisms are unable to resolve the transient state of vascular underfill seen in this period in normal gestation.
From 1986 to 1994, 10 patients were observed to have developed an acute aortic dissection at some stage after an aortic valve replacement (AVR). Study of the characteristics of these patients showed that all patients had an aortic diameter of 50 mm or more (range 50 to 80 mm, mean 64 mm), and 70% suffered from systemic hypertension. Subsequently, the echocardiographic database, containing data from 33,105 studies in 21,484 patients, was searched for cases of AVR in which an accurate aortic dimension could be measured. Of 524 patients who had undergone AVR, an accurate aortic diameter was recorded in 419. Thirty-seven patients had an aortic size greater than 50 mm. All acute dissections occurred in this group of patients. The incidence of acute dissections among patients with significant aortic dilatation following AVR was 27%, whereas the overall incidence of acute dissection after AVR is 0.6%. Although there was a preponderance of tilting disc mechanical valves in the dissecting patients, the type of valve implanted does not seem to be of any importance. From these observations, we conclude that implantation of a valved conduit is indicated even in the presence of mild annuloaortic ectasia (aortic size = 50 mm). Patients who have had an AVR and show an enlarging aortic diameter exceeding 50 mm should have an elective reoperation at an early stage, especially when systemic hypertension is present.
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