title: Short- and long-term outcomes in non-aneurysmal non-perimesencephalic subarachnoid hemorrhage.
abstract: OBJECTIVE
  Our aim was to assess the short- and long-term prognosis in patients suffering from non-aneurysmal non-perimesencephalic SAH (Na-NPM-SAH).
  
  
  METHODS
  Based on admission CT-scan, SAH was categorized as perimesencephalic (PM) or non-perimesencephalic (NPM). Based on digital subtraction angiography (DSA) results, patients were classified as normal DSA (Na-SAH) or aneurysmal SAH (aSAH). Between 1997 and 2010, 67 of 571 patients with non-traumatic SAH (11.7%) suffered from non-aneurysmal non-perimesencephalic SAH. Retrospective analyses of the 67 patients were undertaken, and compared with the aneurysmal SAH group. Long-term follow-up was assessed.
  
  
  RESULTS
  The cohort consisted of 67 Na-NPM-SAH patients, mean age 54.8 years (range: 21-84), 56.7% male. Acute phase: 10.4% mortality and 3% rebleeding (two patients) during the acute phase. Long-term: extensive follow-up was possible in all except one of the survivors at discharge. Mortality was 6.6% during the 510 patient-years follow-up period (median follow-up time per patient, 8.95 years); rebleeding rate was 0-1.6%. An aneurysmal source was found in 13% of patients who underwent a second angiography. Aneurysmal SAH: 312 patients, with confirmed aneurysm by angiography. The mortality rate for Na-NPM-SAH during the acute phase was 10.4%, vs. 20% for aneurysmal SAH in the general database, p = 0.049.
  
  
  CONCLUSIONS
  Na-NPM-SAH patients without an identifiable bleeding source on initial angiography might have a more benign short- and long-term prognosis than aneurysmal SAH patients. Our study confirms an important diagnostic advantage of a second arteriography. Still, despite the major concern of an undetected aneurysm, the long-term rebleeding rate was low in this subgroup of patients.
authors.affiliation: a Department of Neurology , HU La Fe , Valencia , Spain.
authors.forename: Aida
authors.initials: A
authors.lastname: Lago
authors.affiliation: a Department of Neurology , HU La Fe , Valencia , Spain.
authors.forename: Rogelio
authors.initials: R
authors.lastname: López-Cuevas
authors.affiliation: a Department of Neurology , HU La Fe , Valencia , Spain.
authors.forename: Jose Ignacio
authors.initials: JI
authors.lastname: Tembl
authors.affiliation: a Department of Neurology , HU La Fe , Valencia , Spain.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Fortea
authors.affiliation: a Department of Neurology , HU La Fe , Valencia , Spain.
authors.forename: David
authors.initials: D
authors.lastname: Górriz
authors.affiliation: b Department of Radiology , HU La Fe , Valencia , Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Aparici
authors.affiliation: a Department of Neurology , HU La Fe , Valencia , Spain.
authors.forename: Vera
authors.initials: V
authors.lastname: Parkhutik
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D013030:Spain / Q000453:epidemiology; D013345:Subarachnoid Hemorrhage / Q000145:classification* / Q000000981:diagnostic imaging / Q000453:epidemiology*; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: Non-aneurysmal SAH; Non-perimesencephalic SAH; Outcome; SAH; SAH of unknown origin