Outcome and prognostic factors after delayed second subarachnoid haemorrhage.

Background: Data of patients suffering from delayed second subarachnoid haemorrhage (SAH) after aneurysm treatment are still missing. Patients become clearly older than before. Thus, the risk suffering from a second delayed SAH rises. The aim of this study was to analyse clinical outcome and prognostic factors in patients after delayed second SAH.

Method: From 1999 to 2013, 18 of 1,493 patients (1.2%) suffered from a second SAH. Clinical and radiological characteristics were entered into a prospective conducted database. Outcome was assessed according to modified Rankin Scale 6 months after second SAH. P < 0.05 was considered statistically significant.

Results: Eighteen patients were admitted to our department with a second SAH. The second SAH occurred at a mean interval of 144 months after surgical treatment and 78 months after endovascular treatment (P < 0.05), with an overall mean interval of 125 months. The earliest event of second SAH was after 35 months. In 11 (61%) patients, a de novo aneurysm was detected; in one patient (6%), no cause of second SAH was detected. In six (33%) cases, re-rupture of the formerly secured aneurysm was found. Half of the rebleedings occurred from a basilar aneurysm, 33% from an aneurysm of anterior communicating artery and in one patient from a median cerebral artery aneurysm. At second SAH, 8 of 18 patients presented WFNS grade I-III at time of admission (44%). Overall, favourable outcome was achieved in seven patients (39%). Four patients died (22%), one of them before treatment. Favourable outcome seems to be associated with younger age. In our patients, 39% achieved a favourable outcome after second SAH.

Conclusions: A delayed second SAH is a rare entity. After delayed second SAH, age seems to be a prognostic factor for patients' outcome and patients seem to have a worse prognosis. Nonetheless, up to 40% of patients can achieve a favourable outcome.