ABSTRACT
A 73-year-old woman with severe aortic stenosis was accepted for transcatheter aortic valve implantation. There was minimal paravalvular leakage after the implantation, and the patient was stable. Twelve minutes after the implantation, the arterial pressure suddenly dropped. Transesophageal echocardiography showed severe left ventricular dysfunction. Cardiopulmonary resuscitation was started, and initially was successful with a systolic blood pressure of 90 mm Hg. However, despite initiation of extracorporeal circulation support, the patient deteriorated, pulmonary edema developed, and she died. Autopsy revealed an inverted aortic valve. The reasons why the patient had cardiac arrest and an inverted transfemoral aortic valve remain unclear.
Subject(s)
Aortic Valve Stenosis/surgery , Aortic Valve/surgery , Heart Valve Prosthesis Implantation/methods , Heart Valve Prosthesis , Intraoperative Complications/etiology , Prosthesis Failure/adverse effects , Aged , Fatal Outcome , Female , Femoral Artery , HumansABSTRACT
OBJECTIVE: Glutamate has been claimed to protect the heart from ischemia and to facilitate metabolic and hemodynamic recovery after ischemia. The GLUTAmate for Metabolic Intervention in Coronary Surgery trial investigated whether an intravenous glutamate infusion given in association with surgery for acute coronary syndrome could reduce mortality and prevent or mitigate myocardial injury and postoperative heart failure. METHODS: In the present prospective, triple-center, double-blind study, 861 patients undergoing surgery for acute coronary syndrome were randomly assigned to an intravenous infusion of glutamate (n = 428) or saline (n = 433) perioperatively. RESULTS: The incidence of the primary endpoint--a composite of 30-day mortality, perioperative myocardial infarction, and left ventricular heart failure at weaning from cardiopulmonary bypass-was 7.3% versus 5.8% (P = .41) in the glutamate and control groups, respectively. Patients with left ventricular failure at weaning from cardiopulmonary bypass had a shorter median intensive care unit stay (25 vs 92 hours; P = .02) if they were treated with glutamate. In patients with unstable angina (Canadian Cardiovascular Society class IV) undergoing isolated coronary artery bypass grafting (n = 458), the incidence of severe circulatory failure according to the prespecified criteria was significantly lower in the glutamate group (1.3% vs 6.9%; P = .004). On multivariate analysis, glutamate infusion was associated with a reduced risk of developing severe circulatory failure (odds ratio, 0.17; 95% confidence interval, 0.04-0.72; P = .02). A relative risk reduction exceeding 50% for developing severe circulatory failure was seen in most risk groups undergoing isolated coronary artery bypass grafting, with those with diabetes a notable exception. CONCLUSIONS: The primary endpoint did not differ significantly between the groups. The secondary outcomes and post hoc analyses warrant additional studies with regard to the potential beneficial effect of glutamate on postischemic myocardial recovery.
Subject(s)
Acute Coronary Syndrome/surgery , Coronary Artery Bypass/adverse effects , Glutamic Acid/administration & dosage , Heart Failure/prevention & control , Myocardial Infarction/prevention & control , Ventricular Dysfunction, Left/prevention & control , Acute Coronary Syndrome/mortality , Aged , Coronary Artery Bypass/mortality , Double-Blind Method , Female , Heart Failure/etiology , Heart Failure/mortality , Humans , Infusions, Intravenous , Male , Middle Aged , Multivariate Analysis , Myocardial Infarction/etiology , Myocardial Infarction/mortality , Odds Ratio , Prospective Studies , Risk Assessment , Risk Factors , Sodium Chloride/administration & dosage , Sweden , Time Factors , Treatment Outcome , Ventricular Dysfunction, Left/etiology , Ventricular Dysfunction, Left/mortalityABSTRACT
BACKGROUND & AIMS: Concerns have been raised about potential neurological injury related to exogenous glutamate. In cardiac surgery glutamate has been administered as a putative cardioprotective agent by cardioplegia or intravenous infusion. In the GLUTAMICS trial, in addition to surveillance of clinical neurological injuries, a prespecified subgroup was analyzed with regard to postoperative S-100B levels to detect potential subclinical neurological injury related to glutamate infusion. METHODS: Sixty-nine patients operated on for unstable coronary syndrome were randomized to intravenous infusion of glutamate (n=35) or saline (n=34) perioperatively. Plasma levels of S-100B were obtained on the third postoperative day. RESULTS: S-100B in the glutamate group and the control group were 0.079+/-0.034microg/L and 0.090+/-0.042microg/L respectively (p=0.245). There were no patients with stroke or mortality. Three patients in the control group and two in the glutamate group had postoperative confusion. These patients had significantly elevated S-100B compared with those without confusion (0.132+/-0.047vs 0.081+/-0.036microg/L; p=0.003). Overall, 21 patients had S-100B above reference level (> or =0.10microg/L) and these patients had significantly more calcifications in the ascending aorta on epiaortic scanning. CONCLUSIONS: Intravenous glutamate infusion during surgery for unstable coronary artery disease did not initiate a sustained elevation of plasma S-100B. Thus, no evidence for subclinical neurological injury related to glutamate infusion was found. In contrast, postoperative elevation of plasma S-100B was linked to calcification of the ascending aorta and postoperative confusion.