Does prophylactic sotalol and magnesium decrease the incidence of atrial fibrillation following coronary artery bypass surgery: a propensity-matched analysis

Background  

Atrial fibrillation can occur in up to 40% of patients undergoing coronary surgery.     

Intimal hyperplasia and coronary flow reserve after heart transplantation: association with big endothelin-1

BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.     

Use of sonography to evaluate carotid atherosclerosis in the elderly. The Cardiovascular Health Study. CHS Collaborative Research Group

Carotid sonography is being performed on more than 5,000 participants in the Cardiovascular Health Study, a prospective, multicenter study of cardiovascular disease in men and women aged 65 years and older. The sonographic methods used to examine and measure the extracranial carotid arteries are described. Initial validation studies were performed on 61 subjects with a mean age of 68.6 years. Analysis of within- and between-sonographer differences and between-reader differences were performed for selected variables. In general, the mean absolute differences for within- and between-sonographer comparisons were small, with even less variability between readers. Variability was less for the common carotid artery than for the internal carotid artery. These data suggest that carotid sonography is a reliable and reproducible method for use in the study of carotid atherosclerosis in population studies.     

Beta-blockers and primary prevention of coronary heart disease in patients with high blood pressure

We conducted a population-based, case-control study to determine whether beta-blockers, used for the treatment of hypertension, prevent first events of coronary heart disease. Cases were patients who had high blood pressure treated with medicines and who presented in 1982 to 1984 with angina or fatal or nonfatal myocardial infarction. Controls were a probability sample of health maintenance organization patients with pharmacologically treated hypertension and free of coronary heart disease. Blinded to case-control status, we reviewed the medical records of the 248 cases and 737 controls. The health maintenance organization's computerized pharmacy database was used to ascertain the use of beta-blockers. Fewer cases than controls were taking beta-blockers. This difference was confined to those with nonfatal infarctions. After adjustment for confounding, the estimated relative risk was 0.62 (95% confidence interval, 0.39 to 0.99). Higher doses of beta-blockers conferred greater protection. We conclude that beta-blockers may prevent first events of nonfatal myocardial infarction in patients with high blood pressure.     

A randomized controlled trial of sedation in the critically ill

A randomized controlled trial comparing: a) a combination of oral chloral hydrate and promethazine to b) a continuous intravenous midazolam infusion, for maintenance sedation in critically ill children, was carried out. The level of sedation was assessed four hourly using a specifically devized sedation scale. Forty-four children entered the study of whom two were subsequently excluded. The number of satisfactory assessments (desired and actual levels of sedation equal) was significantly greater in the chloral hydrate and promethazine group (Chi-squared P <0.01; confidence intervals of the difference 0.06 to 0.20). The number of assessments at level 5 on the sedation scale (patient restless/distressed) was significantly greater in the midazolam group (Chi-squared P <0.05). The total number of satisfactory assessments in the two groups were only 61 and 48% respectively, suggesting that sedation can be considerably improved. Chloral hydrate and promethazine are more effective than midazolam as maintenance sedation in critically ill children. It is possible to prospectively study the efficacy of sedative drugs in critically ill children.