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R Elliot

Publications and source records attributed to R Elliot.

8 recordsLinked to original sources
PubMed1994

Effect of propranolol on prevention of first variceal bleed and survival in patients with chronic liver disease.

BACKGROUND: Propranolol has been shown to be effective in both primary and secondary treatment of variceal haemorrhage; most primary prevention trials have only included patients with large oesophageal varices. AIM OF THE STUDY: The aim of this study was to look at the effect of propranolol in the primary prevention of variceal bleeding and its long-term effects on mortality in unselected patients with chronic liver disease. METHODOLOGY: Three hundred and nineteen patients were included in a double-blind parallel group study in three centres to receive propranolol 160 mg long-acting (LA) or placebo. Patients were followed up for a minimum of one year. RESULTS: There were eleven episodes of variceal bleeding and 38 deaths with no statistically significant difference in bleeding rates between the two treatment groups. Child's group and history of ascites were the most important prognostic factors determining the likelihood of early death and variceal bleeding respectively. CONCLUSIONS: In this study we failed to demonstrate a significant effect of propranolol on first variceal bleeding or in prolonging survival in unselected patients with chronic liver disease. Our results, however, might have been influenced by the low event rate observed in these unselected group of patients and suggest that careful selection of patients who are most likely to benefit from propranolol is important.

Adult↗
PubMed1978

Failure of high doses of propranolol to reduce experimental myocardial ischemic damage.

Myocardial creatine phosphokinase (CPK) activity and myocardial blood flow (MFB, 15 +/- mu microspheres) were measured at 24 hours after ligation of the left anterior descending coronary artery in nine untreated anesthetized dogs, in eight dogs pretreated with intravenous propranolol 5 mg/kg and in eight which had both pretreatment as well as infusion of propranolol (1.25 mg/kg/hour) after occlusion. Loss of CPK activity from the border and center zones of the myocardial infarct was similar in extent in dogs which had pretreatment but no infusion of propranolol as it was in the control group. Loss of CPK from the center zone was greater (P less than 0.005) in dogs receiving pretreatment followed by constant infusion of the drug. Propranolol had no significant effect on collateral blood flow to the border or center zone of the infarct. In separate experiments, there was no important difference in hemodynamic measurements, except a slower heart rate (P less than 0.01), when pretreated dogs were compared with control dogs up to 2 hours after coronary ligation. We conclude that propranolol given in this dose does not influence nyocardial damage, on the basis of regional myocardial blood flow or tissue CPK depletion values at 24 hr after coronary occlusion.

Animals↗
PubMed1976

Relationship between epicardial ST-segment elevation and myocardial ischemic damage after experimental coronary artery occlusion in dogs.

The relationship between early and late epicardial electrocardiographic changes as well as those in regional myocardial blood flow (MBF) and the severity of myocardial damage was determined in 12 anesthetized dogs with left anterior descending coronary artery ligation. Radioactive microspheres (15 mum) were used to measure regional MBF at 15 min (early) and 24 h (late) after coronary occlusion. Severity of myocardial damage was assessed by the extent of myocardial creatine phosphokinase depletion 24 h after coronary ligation. There was a close linear correlation between myocardial creatine phosphokinase activity and regional MBF both early (r=0.93, 2P less than 0.001) and late (r=0.88, 2P less than 0.001). An inverse but less precise relationship existed between acute epicardial ST-segment elevation and early (r=-0.41, 2P less than 0.001), or late (r=0.35, 2P less than 0.05) regional MBF. Similarly, a weak correlation was found between myocardial creatine phosphokinase (IU/mg protein) at 24 h and early epicardial ST (millivolt) elevation (r=-0.36, 2P less than 0.02). In the center zones of the infarct with MBF 1/10 of normal, about 35% of the areas with normal QRS width had no epicardial ST-segment elevation 15 min after coronary occlusion. About 44% of the areas which developed pathological Q-waves in the electrocardiogram at 24 h had no ST elevation 15 min after coronary ligation. Late evolution of abnormal Q-waves occurred almost invariably in areas in which the early MBF was reduced to less than 50% of normal and in areas which subsequently had myocardial creatine phosphokinase levels reduced to less than 60% of normal. After coronary occlusion, the severity of the ultimate myocardial damage, which was directly proportional to the degree of reduction in MBF, was therefore not reliably predicted by the early epicardial ST-segment elevation. The data obtained in these studies suggest the need for caution in the use of acute ST-segment elevation as a predictive index of the extent or severity of myocardial ischemic damage.

Animals↗
PubMedDate not supplied

Auxiliary substructure for screw-retained prostheses.

A double framework system is indicated when implant location could result in an overcontoured or compromised metal ceramic prosthesis. Precise design of the auxiliary substructure should provide for all necessary reorientations and corrections before constructing the metal ceramic framework. The additional cost and complexity of this technique must be weighed against the esthetic and morphologic requirements of the patient.

Adult↗