Correlation between cardiac enzyme elevation and the duration of cardiopulmonary resuscitation.

Cardiovascular disease is the leading cause of death in the United States. Acute myocardial infarction (MI) is defined as necrosis of myocardial cells. Several studies have shown that cardiac markers are elevated after successful cardiopulmonary resuscitation (CPR) due to physical as well as electrical trauma. Correlation has never been established between an elevation in cardiac markers and patient age, the amount of trauma induced during resuscitation, or the duration of chest compression. Previous studies have determined that cardiac troponin (cTnl) is the most sensitive marker in cardiac injury. In this study, we hypothesized that the duration of CPR and the patient's age had a direct correlation with cardiac injury demonstrated as an elevation of cTnl. We analyzed retrospectively 81 patients that underwent successful CPR in an in-hospital setting. 13 patients were excluded from the analysis due to positive cTnl prior to cardiac arrest. Duration of CPR, as well as cTnl levels before and after cardiac arrest were recorded and analyzed in the remaining 68 patients. Patients with a negative cTnl after successful CPR (n=30) were stratified into Group A. The remaining patients (Group B) had a positive cTnl ranging from 2.2-31 ng/ml. The mean age and the mean duration of CPR in minutes were calculated and compared using t-Test analysis. There was no statistical difference in age between Group A and Group B. Patients in Group A had a mean CPR duration of 12.2 minutes, while patients in Group B had a mean CPR duration of 19.8 minutes (p < 0.02). We found that the duration of cardiopulmonary resuscitation was positively associated with the elevation of cardiac markers.

Etiology of cerebrovascular accidents in octogenarians.

Stroke is the third leading cause of death in the United States, after coronary heart disease and cancer. Many survivors are left with mental and physical impairment and require assistance with activities of daily living. Twenty-eight percent of patients with stroke are under 65 years of age. We analyzed retrospectively 213 elderly patients with the diagnosis of ischemic cerebrovascular event that were consecutively admitted to the stroke unit of our institution between January 2002 and December 2004. Patient age varied from 65 to 100 years (mean = 79.8 years), and there were 66.19% females and 33.81% males. We analyzed the head CT findings of all the patients and separated the patients into two groups based on the results. Patients in Group I had large infarcts on CT and extensive neurological deficits, while patients in Group II had small lacunar infarcts and minor neurological findings. The charts of all the patients were reviewed retrospectively and data on hypertension, diabetes mellitus, carotid stenosis, atrial fibrillation, left ventricular hypertrophy and anticoagulation were retrieved and analyzed. Our results showed that 35.6% (76) of the patients suffered a major stroke (Group 1) and the remainder 64.4% (137) suffered small lacunar strokes (Group 2). More than half (57.9%) of the patients in Group I were found to have atrial fibrillation and significant carotid stenosis (35.5%) and 22.4%), respectively. The remaining patients (28) were hypertensive and 12% had diabetes mellitus, but no extracerebral source of embolism was found. In Group II, only 13.1% were found to have atrial fibrillation or significant carotid stenosis, but all were hypertensive and 86% suffered from diabetes. Our results indicate that major strokes are less prevalent in the geriatric population than small lacunar strokes and tend to be more related to hypertension and diabetes.

Troponin I as a marker of doxorubicin induced cardiotoxicity.

Doxorubicin is a chemotherapeutic agent successfully used in the treatment of a wide range of cancers. However, with cumulative doses, doxorubicin also is known to have cardiotoxic effects, including cardiomyopathy and heart failure. Identification and quantification of myocardial cell damage has been a point of Controversy. We sought to identify these changes by measuring the levels of troponin I both 24 and 48 hr after the administration of doxorubicin as part of an antineoplastic treatment regimen. Thirty-eight patients scheduled to undergo treatment with doxorubicin were screened and approached for enrollment in the study. Thirty-one of them fulfilled all the inclusion criteria and also signed informed consent. All the patients enrolled in the study had blood drawn before the administration of doxorubicin and also 24 and 48 hr later. Electrocardiograms were performed prior to and 48 hr following the administration of chemotherapy. The dose of doxorubicin administered was calculated by the oncologist and ranged from 450 mg/m2-650 mg/m2 (mean 520 mg/m2). Only one patient was found to have en elevation of troponin levels both 24 and 48 hr (2.3 ng/mL and 2.1 ng/mL, respectively) after the administration of the drug. During that time, the patient denied any chest pain, shortness of breath or palpitations. Repeat ECG did not show any changes from the baseline. The remaining participants continued to maintain a troponin level of less than 0.3 ng/mL during the follow-up. In these patients, no electrocardiographic changes were noted in the follow-up ECG compared to the baseline; however, a slight drop in the ejection fraction without any impact on the clinical presentation was recorded. We concluded that the cTnl level does not change after the administration of doxorubicin, and thus cannot be used as a predictor of doxorubicin-induced cardiotoxicity.