Myocardial Ischemia and Vasospasm in Aneurysmal SAH

描述（由申请人提供）：蛛网膜下腔出血（SAH）后前5天内的心肌功能障碍包括心律失常、缺血和“神经源性顿抑心肌”。“一部分患者肌钙蛋白I水平升高，表明心肌缺血和梗死。 然而，心肌缺血在这一人群中的真实发病率是未知的，因为缺血发作是短暂的、未被发现的或致命的。 本申请将前瞻性评价SAH人群中心肌缺血和梗死的发生率，并确定心肌缺血的存在是否显著增加症状性血管痉挛（SV）（SAH后的主要并发症）的风险。 本申请的中心假设是，SAH后立即发生的儿茶酚胺激增（去甲肾上腺素（NE）肾上腺素（EPI））提供了与心肌和脑血管血管痉挛相关的常见机制，增加了继发性心肌和脑缺血和梗死的风险。 具体目标是：1）确定儿茶酚胺释放（NE，EPI）的幅度与心肌缺血和梗死的发生之间的关联，（如通过ECG心律失常（ST改变和T波倒置）检测到的，心室功能降低; CB-K、CPK升高，和cTnI水平））和2）确定SAH后前5天内心肌缺血和梗死的存在是否会增加SAH后14天内SV的风险。 将采用前瞻性、纵向、受试者内组间重复测量设计，所有受试者将接受血清（NE、EPI、心肌酶）连续采样，同时进行强化神经生理学监测、每日床旁便携式超声心动图筛选和临床检查，以检测是否存在心肌梗死和缺血以及SV结局。

DESCRIPTION (provided by applicant): Myocardial dysfunction within the first five days following aneurysmal subarachnoid hemorrhage (SAH) includes dysrhythmia, ischemia and "neurogenic stunned myocardium." A subset of patients has elevated troponin I levels indicative of myocardial ischemia and infarct. However, the true incidence of myocardial ischemia in this population is unknown in that ischemic episodes are short-lived, undetected, or deadly. This application will prospectively evaluate the incidence of myocardial ischemia and infarct in the SAH population and determine whether the presence of myocardial ischemia significantly increases the risk of symptomatic vasospasm (SV), a major complication following SAH. The central hypothesis of this application is that a catecholamine surge (norepinephrine (NE) epinephrine (EPI)) immediately after SAH provides a common mechanism associated with both vasospasm of the myocardial and cerebral vessels that increases the risk for secondary myocardial and cerebral ischemia and infarct. The specific aims are to: 1) determine the association between the magnitude of the catecholamine release (NE, EPI) the occurrence of myocardial ischemia and infarct (as detected by ECG arrythmias (ST changes and T wave inversion), decreased ventricular function; elevated CB-K, CPK, and cTnI levels)) and 2) determine whether the presence of myocardial ischemia and infarct within the first 5 days after SAH increases the risk of SV within 14 days following an SAH. A prospective, longitudinal, within-subject between-group repeated measure design will be used in that all subjects will undergo serial sampling of serum (NE, EPI, cardiac enzymes) concurrent with intense neurophysiologic monitoring, daily bedside portable echocardiography screening and clinical examinations in order to detect the presence of the outcomes of myocardial infarct and ischemia and SV.