Many aspects of the aneurysm surgery including the timing of the surgery and outcome predictors are still controversial (
11). The authors have different trends to advocate either early or late surgery due to the risk of vasospasm and surgical complications. Moreover, the prognostic factors and predictive clinical conditions of the surgical outcome in the aneurysm surgery are also controversial (
12,
13). Grading of the SAH, changes in the blood pressure, electrocardiogram, hyponatremia, haptoglobin genotype, neuropeptides, and several biomarkers have been proposed and assessed to predict the risk of vasospasm and outcome after the SAH or aneurysm surgery (
14-
17).
No consensus exists regarding the timing for the surgical treatment of the ruptured intracranial aneurysms. Ross et al. (
18) prospectively investigated 1168 patients that were divided into three groups based on the time of the surgical intervention. Their results indicated that the only independent variables affecting the outcome were age and clinical grading at presentation, and they concluded that the time of surgery did not significantly affect the surgical outcome. Similar results have been achieved by some other authors regarding the time of surgery (
19,
20). Conversely, other researchers concluded that the outcome is unsatisfactory when the surgery is done during the intermediate period of the event, owing to the increased risk of the vasospasm (
21,
22).
The risk of vasospasm and its related morbidities in aneurysm surgery during the intermediate phase (days 4 - 15) is obvious (
23). Several clinical conditions and factors have been investigated in the pathophysiological study of the vasospasm (
24). An important clinical condition, which is commonly observed in the ruptured ACoA aneurysm, is the presence of the blood in the ventricular cavity. Although 53% of the ruptured ACoA aneurysms are accompanied by IVH (
25), its effect on surgical outcome and its relationship with the timing of the surgery have not been discussed in detail.
Although the early surgery is not agreed by all, it has been recommended by many authors in the previous related studies (
26,
27). A better surgical outcome decreases the fatal re-bleeding rate, and hospital stay has been stated as the benefits of the early surgery (
18,
28). We also agree with the early aneurysm clipping as the main strategy in the treatment of uncomplicated cases. Nevertheless, in some cases, more considerations may be needed.
In our experience with the microsurgical treatment of the ruptured ACoA aneurysm, the presence of IVH was a significant negative outcome indicator. The patients with ruptured ACoA aneurysm, whose initial CT scans had been accompanied by the IVH, had overall a worse surgical outcome compared to the patients without IVH. Nevertheless, with respect to the time of the surgery, the surgical outcome was more satisfactory in patients that received delayed microsurgical treatment when IVH had been observed on the initial CT scan.
The exact pathophysiology leading to a worse outcome in patients with the IVH is still unclear. We speculate this must be attributed to brain natriuretic peptide (BNP) hypersecretion due to direct damage to the hypothalamus by the passing blood to the third ventricle through the ruptured lamina terminalis. BNP is considered an important cause of development of the cerebral vasospasm in SAH. Sviri et al. (
29) studied the relationship of BNP with post cerebral vasospasm and found a strong correlation between BNP and vasospasm. They demonstrated that the BNP level significantly increased in patients with IVH due to ACoA involvement. They assumed that close anatomical proximity of the hypothalamic perforating vessels to the ACoA complex increased the risk of hypothalamic damage to the ruptured ACoA aneurysm and a higher chance of alterations in the secretion level of BNP (
30).
Although the detailed molecular pathophysiology of the involved mechanism needs further investigations, our results indicated that the outcome was significantly better in patients who had received a delayed microsurgical treatment when ruptured ACoA was accompanied by the IVH. Based on our study, it could be assumed that the leakage of the blood into the third ventricle in the ruptured ACoA exposed the patients to the higher risk of surgical morbidities. Therefore, delayed surgery might be more effective in the group of patients with ACoA aneurysm.
4.1. Conclusions
In patients with SAH having aneurysms located in the ACoA that caused lamina terminalis damage associated with the third ventricular hemorrhage, delayed surgery was significantly associated with better outcome.