Patient height as a risk factor for poor outcome in acute type B aortic dissection.

Background: Height has been shown in epidemiological studies to have mixed associations with long-term mortality. Shorter stature is related to higher all-cause and coronary disease mortality, and taller stature is related to higher cancer and aortic aneurysm mortality. We evaluated height as a predictor of acute aortic dissection complexity and long-term mortality in a cohort of patients with acute type B aortic dissection.

Methods: Between February 2001 and January 2014 we treated 461 acute type B aortic dissections. Median age was 60 years (range 16 to 98). 175/461 (38%) were female, and 286 (62%) were male. Patients with uncomplicated dissection were managed medically, with blood pressure control and anti-impulse therapy as the main objectives. Patients with symptomatic malperfusion were managed by a variety of techniques, including open aortic surgical repair or stent grafting, branch vessel bypasses and flap fenestration as appropriate. Patients were followed with imaging and management of new symptoms. The upper quartile of height in our population (>180 cm) was considered tall for the analysis.

Results: Malperfusion or persistent symptoms were present in 154/461 (33.4%) patients at some time during the acute presentation. Presence of malperfusion-related complications was monotonically related to height, with complication rates of 23% in patients with height less than 165 cm, 31% in those with height between 166 and 173 cm, 39% at height between 173 and 180 cm, and 40% above 180 cm of height (P<0.02). Occurrence of complicated dissection was estimated to be nearly 50% at a height of 190 cm by logistic regression analysis. Independent predictors of long-term mortality were complication (Hazard Ratio-HR 1.67, P<0.006), glomerular filtration rate (GFR) below 60 (HR 2.33, P<0.0001), and height >180 cm (HR 1.60, P<0.02). Five year survival estimates (adjusted for GFR and presence of complications) were 81% in the group with 180 cm or less in height and 63% in the group with height above 180 cm.

Conclusions: Optimal management of acute type B aortic dissection is controversial. Identifying correlates of complicated acute dissection, such as height, could help to clarify the setting in which intervention is most appropriate. Height above 180 cm is an independent risk factor for long-term mortality, and should be considered in planning the management of acute type B aortic dissection.