Background and Purpose-Cerebral blood flow (CBF) is reduced after subarachnoid hemorrhage (SAH), and symptomatic vasospasm is a major cause of morbidity and mortality. Volume expansion has been reported to increase CBF after SAH, but CBF values in hypervolemic (HV) and normovolemic (NV) subjects have never been directly compared. Methods-On the day after aneurysm clipping, we randomly assigned 82 patients to receive HV or NV fluid management until SAH day 14. In addition to 80 mL/h of isotonic crystalloid, 250 mL of 5% albumin solution was given every 2 hours to maintain normal (NV group, nϭ41) or elevated (HV group, nϭ41) cardiac filling pressures. CBF ( 133 xenon clearance) was measured before randomization and approximately every 3 days thereafter (mean, 4.5 studies per patient). Results-HV patients received significantly more fluid and had higher pulmonary artery diastolic and central venous pressures than NV patients, but there was no effect on net fluid balance or on blood volume measured on the third postoperative day. There was no difference in mean global CBF during the treatment period between HV and NV patients (Pϭ0.55, random-effects model). Symptomatic vasospasm occurred in 20% of patients in each group and was associated with reduced minimum regional CBF values (Pϭ0.04). However, there was also no difference in minimum regional CBF between the 2 treatment groups. Conclusions-HV therapy resulted in increased cardiac filling pressures and fluid intake but did not increase CBF or blood volume compared with NV therapy. Although careful fluid management to avoid hypovolemia may reduce the risk of delayed cerebral ischemia after SAH, prophylactic HV therapy is unlikely to confer an additional benefit. (Stroke. 2000;31:383-391.)
Background and Purpose-Electrocardiographic abnormalities and elevations of the creatine kinase myocardial isoenzyme (CK-MB) occur frequently after subarachnoid hemorrhage. In some patients, a reversible and presumably neurogenic form of left ventricular dysfunction is demonstrated by echocardiography. It is not known whether cardiac injury of this type adversely affects cardiovascular hemodynamic performance. Methods-We retrospectively studied 72 patients admitted to our neuro-ICU for aneurysmal subarachnoid hemorrhage over a 2.5-year period. We selected patients who met the following criteria: (1) CK-MB levels measured within 3 days of onset, (2) pulmonary artery catheter placed, (3) echocardiogram performed, and (4) no history of preexisting cardiac disease. Hemodynamic profiles were recorded on the day after surgery (nϭ67) or on the day of echocardiography (nϭ5) if surgery was not performed (mean, 3.3Ϯ1.7 days after onset). The severity of cardiac injury was classified as none (peak CK-MB Ͻ1%, nϭ36), mild (peak CK-MB 1% to 2%, nϭ21), moderate (peak CK-MB Ͼ2%, nϭ6), or severe (abnormal left ventricular wall motion, nϭ9). Results-Abnormal left ventricular wall motion occurred exclusively in patients with peak CK-MB levels Ͼ2% (PϽ0.0001), poor neurological grade (Pϭ0.002), and female sex (Pϭ0.02). Left ventricular stroke volume index and stroke work index were elevated above the normal range in patients with peak CK-MB levels Ͻ1% and fell progressively as the severity of cardiac injury increased, with mean values for patients with abnormal wall motion below normal (both PϽ0.0001 by ANOVA). Cardiac index followed a similar trend, but the effect was less pronounced (PϽ0.0001). Using forward stepwise multiple logistic regression, we found that thick subarachnoid clot on the admission CT scan (odds ratio, 1.9; 95% confidence interval [95% CI], 1.0 to 3.4; Pϭ0.04) and depressed cardiac index (odds ratio, 2.1; 95% CI, 1.0 to 4.1; Pϭ0.04) were independent predictors of symptomatic vasospasm. Conclusions-Myocardial enzyme release and echocardiographic wall motion abnormalities are associated with impaired left ventricular performance after subarachnoid hemorrhage. In severely affected patients, reduction of cardiac output from normally elevated levels may increase the risk of cerebral ischemia related to vasospasm. (Stroke. 1999;30:780-786.)
A reversible form of cardiac injury may occur in patients with NPE following SAH and is associated with characteristic clinical findings. Impaired LV hemodynamic performance in this setting may contribute to cardiovascular instability, pulmonary edema formation, and complications from cerebral ischemia.
A reversible and presumably neurogenic form of myocardial dysfunction may occur following subarachnoid hemorrhage (SAH), but the relationship of this finding to electrocardiographic abnormalities remains unclear. To clarify this issue, serial electrocardiograms (ECGs, mean 6.2 per patient) and echocardiograms (mean 3.4 days after SAH) were obtained in 57 SAH patients without preexisting cardiac disease. The goal was to determine which specific electrocardiographic changes, if any, reflect abnormal left ventricular wall motion in acute SAH. Wall motion abnormalities were identified in five (8%) of 57 patients. Four of these affected patients experienced hypotension (systolic blood pressure < 100 mm Hg) and three exhibited pulmonary edema within 6 hours of SAH, compared to none of the 52 patients with normal wall motion (p < 0.0001). Patients with abnormal wall motion were more likely than patients with normal echocardiograms to have symmetrical T wave inversion (five of five vs. seven of 52, p < 0.001) and severe (> or = 500 msec) QTc segment prolongation (five of five vs. three of 52, p < 0.001) on serial ECGs. These associations maintained their significance with analysis limited to single ECGs performed on or near the day of echocardiography. Abnormal wall motion was also associated with borderline (2% to 5%) creatine kinase MB elevation (five of five vs. three of 52, p < 0.001) and poor neurological grade (p < 0.0001). Although no combination of findings on a single ECG resulted in 100% sensitivity for abnormal wall motion, the presence of either inverted T waves or severe QTc segment prolongation on serial ECGs was associated with 100% sensitivity and 81% specificity. These results demonstrate an association between reduced left ventricular systolic function, mild creatine kinase MB elevation, and electrocardiographic repolarization abnormalities in acute SAH. Symmetrical T wave inversion and severe QTc segment prolongation best identified patients at risk for myocardial dysfunction and may serve as useful criteria for echocardiographic screening following SAH.
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