Outcome of Stanford type B dissection in patients with Marfan syndrome

The aim of this study was to determine the outcome of Stanford type B aortic dissection in patients with Marfan syndrome (MFS) and to evaluate aortic diameters at time of dissection as well as the impact of previous aortic root replacement.

Analysis of all patients with MFS fulfilling Ghent criteria seen at this institution since 1995 until 2022.

Thirty-six (19%) out of 188 patients with MFS suffered from Stanford type B aortic dissection during the study period. The Mean aortic diameter at the time of dissection was 39.0 mm [95% confidence interval (CI): 35.6-42.3]. The mean pre-dissection diameter (available in 25% of patients) was 32.1 mm (95% CI: 28.0-36.3) and the mean expansion was 19% (95% CI: 11.9-26.2). There was no correlation between age and diameter at the time of dissection (<20, 21-30, 31-40, 41-50, 51-60, <61 years; P = 0.78). Freedom from intervention after dissection was 53%, 44% and 33% at 1, 5 and 10 years. Aortic growth rate in those patients that had to undergo intervention within the 1st year after dissection was 10.2 mm/year (95% CI: 4.4-15.9) compared to 5.8 mm/year (95% CI: 3.3-8.3, P = 0.109) in those thereafter. The mean time between dissection and intervention was 1.8 years (95% CI: 0.6-3.0). While type B dissection seems more frequent after previous elective aortic repair (58% vs 42%), there was no difference between valve-sparing root replacement (VSRR) compared to Bentall procedures [Hazard ratio (HR) for VSRR 0.78, 95% CI: 0.31-2.0, P-value = 0.61]. The mean age of the entire population at the end of follow-up was 42 years (95% CI: 39.2-44.7). The mean follow-up time was 9 years (95% CI: 7.8-10.4).

Stanford type B dissection in patients with MFS occurs far below accepted thresholds for intervention. Risk for type B dissection is present throughout lifetime and two-thirds of patients need an intervention after dissection. There is no difference in freedom from type B dissection between a Bentall procedure and a VSRR.