Page 31 - Cardiac abnormalities after aneurysmal subarachnoid hemorrhage

Impact of cardiac complications on outcome after aneurysmal subarachnoid hemorrhage
Additionally, heterogeneity of the data (I2) is presented. WMAs, elevated troponin and (NT-pro-)BNP levels, tachycardia, Q waves, ST depression and T wave abnormalities were significantly associated with an increased risk of death. Bradycardia was significantly associated with a higher chance of survival. However, Q waves and ST depression had significantly heterogeneity.
Figure 2B shows the poor outcome data. Elevated troponin and CK-MB levels and 2 ST depression were significantly associated with poor outcome.
Figure 2C presents the pooled RRs for cardiac abnormalities on DCI. WMAs, elevated
troponin, CK-MB, and (NT-pro)BNP levels and ST depression were significantly
associated with an increased risk of the development of DCI. Heterogeneity for the association of DCI and troponin and BNP levels was high.
Discussion
This meta-analysis patently indicates that cardiac abnormalities after SAH are related to death, poor outcome and DCI. Although the main causes of death and poor outcome after SAH are the initial hemorrhage and neurological complications, we found that also WMAs, troponins, CK-MB, BNP, Q waves, ST depression and T wave abnormalities are associated with death and poor outcome. These markers for cardiac damage and dysfunction are often present after SAH, and are similar to those observed in ischemic heart disease, but the underlying pathophysiological mechanism is probably different.
Several mechanisms for the occurrence of cardiac complications after SAH have been suggested, but none is proven. However, a generally accepted hypothesis is that sympathetic stimulation induces catecholamine release in the myocardium, which may lead to impaired systolic and diastolic function, repolarization abnormalities, and myocardial damage.
In ischemic heart disease, QT prolongation and ST segment elevation are associated with death. Against our expectations, these ECG abnormalities were not associated with death or poor outcome in patients with SAH. Possible explanations for the lack of association are that criteria used for QT prolongation in the articles were heterogeneous and arrhythmias as a cause of death were not reported in the studies. Bradycardia was associated with decreased risk of death. This corroborates with the results of several publications that suggest a beneficial effect of beta-blockade on outcome after SAH.17-20 However, it is unclear whether this beneficial
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