CHICAGO (FRONTLINE MEDICAL NEWS) – Pancreaticoduodenal and gastroduodenal artery aneurysms should be repaired at diagnosis, according to Dr. Michael Corey, a vascular surgeon at Massachusetts General Hospital in Boston.

The reason is “they rupture at small sizes. Most other small splanchnic artery aneurysms” – below 25 mm – “do not grow or rupture over time and can safely undergo surveillance imaging every 3 years,” he said at a meeting hosted by the Society for Vascular Surgery.

The insights come from Dr. Corey’s review of 264 splanchnic artery aneurysms (SAAs) treated at Massachusetts General Hospital from 1994 to 2014 .

Pancreaticoduodenal (PDA) and gastroduodenal (GDA) artery aneurysms were the most likely to cause trouble. Almost all of the 36 in the study were associated with high-grade celiac axis stenosis, and 12 (33%) were symptomatic at presentation, including 7 (19%) that had ruptured at a mean size of 27.4 mm, range 15-48 mm.

Those 7 accounted for more than half of the 13 ruptures in the study. There were also five ruptures among 95 splenic artery aneurysms – the most common aneurysm type in the study – at a mean of 42 mm, and one among 34 hepatic artery aneurysms at 40 mm. Thirty-day morbidity after rupture repair was 54% and mortality 8%.

Pancreaticoduodenal (odds ratio, 14.41; 95% confidence interval, 3.5-59.9; P = .0002) and gastroduodenal artery aneurysms (OR, 6.95; 95% CI, 1.1-45.1; P = .042) were far more predictive of rupture than aneurysm size (OR, 1.04; 95% CI, 1.01-1.08; P = .0042). The strongest predictor was type 4 Ehlers-Danlos syndrome (OR, 34.09; 95% CI, 2.4-479.8; P = .0089). Calcification, meanwhile, did not predict rupture, growth, or thrombus burden.

Dr. Corey and his colleagues reviewed Massachusetts General’s experience with SAAs because “no strong consensus exists in the literature concerning the indications for treatment; 2 cm is currently the indication for surgical treatment of asymptomatic lesions,” he said.

Two centimeters might be too aggressive in some cases. Among 176 aneurysms put under surveillance for a mean of 36.1 months, the mean aneurysm size was 16.3 mm but ranged up to 40 mm. Even so, none of them ruptured. Just 12 aneurysms grew during surveillance, and only 8 eventually needed intervention. Perhaps most “small asymptomatic lesions do not affect longevity,” Dr. Corey said. The mean aneurysm size was 31.1 mm in the 88 patients repaired within 6 months of diagnosis. Splenic, pancreaticoduodenal, gastroduodenal, and hepatic aneurysms were the most likely to be repaired early, the majority by coil embolization and other endovascular techniques. Thirty-day morbidity for intact repair was 13% and mortality 3%.

Most of the splenic artery aneurysms were asymptomatic at presentation. In the half that were watched, just six grew.

Similarly, 78 celiac artery aneurysms – the second most common in the study – all presented without symptoms. Just 3 of the 60 under surveillance grew over a mean of 43.6 months. “These aneurysms rarely change,” Dr. Corey said.

Most of the 34 hepatic artery aneurysms and 17 superior mesenteric artery (SMA) aneurysms were asymptomatic. Between both groups, 20 aneurysms were put under surveillance; growth was noted in 1, an SMA lesion.

Although there was a shift from open to endovascular repair during the study period, there were no statistically significant differences in morbidity or mortality between the two approaches.

Dr. Corey has no disclosures.