Therapeutic anticoagulation for intra-aortic balloon pumps (IABP) in coronary care unit patients is commonly utilized. A more selective strategy for anticoagulation (i.e. only patients with another primary indication for systemic anticoagulation receive heparin) has been suggested to minimize bleeding. A current review of IABP practice with respect to anticoagulation, patient population and its associated risks is timely.

BACKGROUND:Access to new therapies in hospitals depends upon both clinical trial evidence and local Pharmacy and Therapeutics (P&T) committee approval. The process of formulary evaluation by P&T committees is not well-understood.OBJECTIVES:To describe the formulary decision-making process in Canadian hospitals for cardiovascular medications recently made available on the Canadian market.METHODS:Postal survey of hospital pharmacy directors in all Canadian hospitals with more than 50 beds. Target drugs included abciximab, enoxaparin, dalteparin, clopidogrel, eptifibatide and tirofiban.RESULTS:Of 428 surveys mailed, responses were received from 164 P&T committees representing 350 hospitals for an effective response rate of 82%. While physicians make up the largest proportion of committee membership, pharmacists play an influential role. Information most commonly cited as influencing formulary decisions included published clinical trials (97%), regional guidelines (90%), pharmacoeconomic data (84%), decisions at peer hospitals (73%) and local opinion leaders (60%). However, this information was often not required on formulary applications. Approval timelines varied widely for target medications but there were no regional, hospital or P&T committee characteristics that were independent predictors of early formulary application or approval.CONCLUSIONS:There is wide variability in the time taken for Canadian institutions to adopt new cardiovascular therapies, which is not explained by regional, hospital or P&T committee characteristics. Standardization of the formulary application and evaluation processes, including sharing of information amongst institutions, would lead to broader understanding of the applicable issues, more objectivity and improved efficiency.

OBJECTIVE: To define contemporary utilization patterns of anticoagulant and antiplatelet therapy for thromboembolic prophylaxis in atrial fibrillation (AF). DESIGN: Retrospective medical records audit of patients admitted in 1993 and 1994. SETTING: Twelve Canadian hospitals. PATIENTS: Three thousand, three hundred and seventy-five consecutive patients with AF; 1570 females and 2005 males. The mean age was 72 years; 1353 patients were younger than 70 years and 2222 were aged 70 years and older. MEASUREMENTS AND RESULTS: Overall, 1188 (33%) of the 3575 patients received no prophylaxis, 852 (24%) were treated with warfarin alone, 1247 (35%) received acetylsalicylic acid (ASA) alone and 288 (8%) received both drugs. The pattern of medication use did not change appreciably when possible contraindications to warfarin or ASA therapy were considered. Among the 331 AF patients with valvular heart disease and no contraindications to thromboembolic prophylaxis, 65 (20%) received neither treatment, 181 (55%) received warfarin therapy alone, 46 (14%) received ASA alone and 39 (12%) received both. Among the 2199 AF patients with nonvalvular heart disease and no contraindications, 823 (37%) did not receive either therapy, 677 (31%) received ASA alone, 504 (23%) received warfarin alone and 195 (9%) received both. Elderly and female patients were less likely to receive thromboembolic prophylaxis. CONCLUSIONS: Anticoagulation and antiplatelet prophylaxis in AF appears to be less than optimal. Although concerns about bleeding may be one reason thromboembolic prophylaxis is so unevenly and incompletely applied, it will be important to determine the reasons for this practice and to develop effective strategies in order to enhance the process of care and patient outcomes.

Objective: The primary objective of this study was to determine the effect of implementing a critical path on use of proven efficacious therapies and outcomes in patients admitted to a hospital with acute myocardial infarction (AMI). The secondary objectives were to evaluate the use of unproven medications and to develop an understanding of the factors associated with adverse in-hospital outcomes in these patients.Study Design: A nonrandomized before-after study design was used to evaluate the efficacy of a critical path instrument in patients admitted to hospital with AMI.Patients and Methods: Consecutive patients admitted with AMI in nine participating hospitals were enrolled in the study. The critical path instrument consisted of a locally developed, preprinted physician order form. Practice patterns were determined before (n=2305) and after (n=2349) implementation of the critical path by primary chart review. Multivariate analysis of risk factors for mortality was performed on a combined database of 6088 AMI patients.Results: The use of acetylsalicylic acid (ASA), nitrates, and beta blockers increased significantly by 3%, 2%, and 9%, respectively, after implementation of the critical path. Use of thrombolytics remained stable at 41 %, and calcium channel blocker use decreased significantly by 8%. In-hospital mortality decreased by 1%. There was less use of ASA, nitrates, beta blockers, and thrombolytic therapy in women and the elderly. Multivariate analysis showed that advanced age was associated with increased mortality risk, whereas ASA, beta blockers, nitrates, and calcium channel blockers were associated with reduced mortality risk.Conclusion: Implementation of a critical path resulted in increased use of proven efficacious therapies, reduced use of noneffective therapy, and a trend toward reduced mortality.

BACKGROUND: The purpose of this study was to define cardiovascular risk and management in low risk ambulatory patients. METHODS: Case-control, cross-sectional audit of 1806 patients from eight primary care clinics from 1992 to 1994. The case study group comprised 902 patients who had lipid profiles completed within six months of the index audit, and the control group compromised 904 age-, sex- and temporally-matched patients with no lipid measurements. RESULTS: The prevalence of cardiovascular risk factors and risk factor management strategies between the cases and control subjects revealed that all risk factors and risk reduction interventions were significantly higher (P<0.02) among patients with a recent measurement of their serum lipid profile. Logistic regression revealed previous lipid-lowering therapy and history of diabetes or dyslipidemia to be preferentially related to likelihood of serum lipid measurements. CONCLUSIONS: The data suggest that primary care physicians are more aggressive in the investigation of low risk patients with higher prevalence of traditional cardiovascular risk factors, relative to clinically similar patients with lower risk profiles. This practice pattern, based on history-derived risk stratification, is compatible with propagated consensus guidelines on cardiovascular risk reduction and represents an appropriate utilization of health resources by physicians concerned with the prevention of cardiovascular disease.

OBJECTIVE:To determine the utilization of anticoagulant and antithrombotic agents in older patients with atrial fibrillation.DESIGN:Retrospective chart review.SETTING:A geriatric rehabilitation hospital.PATIENTS:Subjects were 102 patients with atrial fibrillation as an intermittent or prevailing cardiac rhythm during a hospital admission in the 1993 fiscal year.MEASUREMENTS:Age, sex, and mental status of the patients; duration and etiology of atrial fibrillation; presence of contraindications to anticoagulants or antithrombotic agents; and utilization of these agents in this population.RESULTS:Of 102 older patients with atrial fibrillation at admission, only 51 were taking some form of anticoagulant or antithrombotic therapy proven effective for stroke prophylaxis (19 warfarin and 32 aspirin). Although 67 patients had relative contraindications to anticoagulation with warfarin, only 25 of the 35 with no contraindications were taking warfarin at the time of discharge. In addition, of the 43 patients with contraindications to warfarin but no contraindications to aspirin, only 28 were prescribed antithrombotic therapy.CONCLUSIONS:Although anticoagulation or antithrombotic therapies for atrial fibrillation appear to be relatively widely used, there are still significant windows of opportunity for the improvement of clinician practice patterns and clinical outcomes in older patients.

Objective: To define contemporary patterns of risk and management among patients with congestive heart failure (CHF).Methods: Cross-sectional records audit of 4606 hospitalized patients with CHF in 1992 and 1993.Results: Overall medication use was diuretics, 82%; angiotensin-converting enzyme inhibitors, 53%; nitrates, 49%; digoxin, 46%; potassium, 40%; acetylsalicylic acid, 36%; calcium antagonists, 20%; warfarin, 17%; beta-blockers, 15%; and magnesium, 10%. Angiotensin-converting enzyme inhibitors were used less frequently in women and patients 70 years or older (P<.01). Total in-hospital mortality was 19%. The most common single cause of death was CHF progression, but noncardiac causes accounted for 30% of all deaths. Logistic regression analysis revealed age 70 years or older and the use of magnesium and nitrates to be associated with increased relative risk of in-hospital mortality; angiotens-inconverting enzyme inhibitors, acetylsalicylic acid, calcium antagonists, beta-blockers, and warfarin were associated with decreased risk.Conclusions: Hospitalized patients with CHF have high all-cause mortality risk and less than optimal use of proven efficacious therapy, particularly among women and the elderly. Increased use of proven CHF therapy would likely decrease the risk of cardiac events, but the competing noncardiac risks in this patient population are high and may not be affected by improved use of efficacious cardiac therapies.

This study defined the patterns of investigation and treatment of serum lipids and other modifiable risk factors for atherosclerosis among 3,304 hospitalized patients at high risk for future cardiovascular events, There were 2,161 men and 1,143 women; 1,955 were aged <70 years, and 1,349 were aged greater than or equal to 70 years. Acute (61%) and chronic (65%) cardiac ischemia was the most prevalent reason for high-risk status, followed by cardiac revoscularization (46%) and diabetes (28%): Only 28% of patients had lipid measurements recorded during their hospital stay, or recorded at any time between 1988 and 1993, A lipid-lowering diet or drugs were 8% of prescribed far 22% and 8% of all patients, respectively, and an adjustment in lifestyle in only 5% of all patients, Moreover, measurement and therapy of lipid risk were recorded less frequently in older patients (p <0.01), and less often in women (p <0.01). Logistic regression analysis revealed admission for revascularization, preadmission lipid-lowering or lifestyle therapies, and history of hyperlipidemia or diabetes to be associated with increased likelihood of in-hospital lipid measurement; age greater than or equal to 70 years was associated with reduced likelihood of lipid determinations (p <0.01), The overall investigation and therapy of serum lipids and other risk factors in acute care patients at high risk for cardiovascular events appear less than optimal, Moreover, there is significantly fewer measurements and less treatment of risk factors in women and older patients, Improvement in these practice patterns would improve patient outcomes far the most important diseases in society.

OBJECTIVE: To offer an attributive opinion of recent improvements in acute myocardial infarction (AMI) practice patterns and patient outcomes in the culture of an active research program. DATA SOURCES: Review of original clinical data from five sequential, consecutively enrolled, AMI patient cohorts and University of Alberta Hospitals from 1987-93. DATA SYNTHESIS: Early cohorts had low use of trial-proven efficacious therapies for AMI, particularly among high risk older and female patients. Over time, there were continuous and marked increases in the use of efficacious therapies and decreased use of nonefficacious therapies, with a paralled decrease in mortality among high risk patients. CONCLUSIONS: In a large tertiary care hospital between 1987 and 1993 the use of evidence-based AMI therapy and survival in high risk patients significantly increased. The continuity and large size of these improvements in AMI practice patterns, compared with similar populations reported in the contemporary literature, suggest it is unlikely they were due to chance. Rather, intercurrent reported measurement and reporting of key health care performance indicators, and initiation of explicit critical path AMI practice guidelines provide a more likely explanation. Future studies by a network of community and university investigators will test whether findings are true for a broad AMI population and whether similar practice definition and improvement tools are effective for other cardiac problems, including the management of congestive heart failure.

Currently with the spread of tunnel constructions in cities, the proximity of other structures being built close to these tunnels have now become an important subject. Studying the rate of settlement of structures built in the vicinity of these tunnels could be an importance as well. The distance between tunnels and buildings is an important factor which can also be taken to account. Considering some of the parameters in place, favorable results can be achieved in having tunnels and other structures in the close proximity of each other.In this paper, the settlement of structures with different scenarios has been studied. The proximity of structures and their orientation in comparison with the location of the tunnels has also been a part of this study. Through the Finite Element Method (FEM), and with the use of Neural Network (NN), a various settlement situations have been studied. Using NN on the analysis of the FEM outcome and consideration of the vertical and horizontal distances between the tunnels and constructions with the number of their stories and the diameter of tunnel, relation between the settlements of constructions in any given direction will be immerge. In the study of this matter, the use of methods such as NN and genetic algorithms has not been reported. Using NN to evaluate the results can help to optimize the construction and implementation of underground structures.

OBJECTIVE:To offer an attributive opinion of recent improvements in acute myocardial infarction (AMI) practice patterns and patient outcomes in the culture of an active health care research program.DATA SOURCES:Review of original clinical data from five sequential, consecutively enrolled, AMI patient cohorts at the University of Alberta Hospitals from 1987-93.DATA SYNTHESIS:Early cohorts had low use of trial-proven efficacious therapies for AMI, particularly among high risk older and female patients. Over time, there were continuous and marked increases in the use of efficacious therapies and decreased use of nonefficacious therapies, with a parallel decrease in mortality among high risk patients.CONCLUSIONS:In a large tertiary care hospital between 1987 and 1993 the use of evidence-based AMI therapy and survival in high risk patients significantly increased. The continuity and large size of these improvements in AMI practice patterns, compared with similar populations reported in the contemporary literature, suggest it is unlikely they were due to chance. Rather, intercurrent repeated measurement and reporting of key health care performance indicators, and initiation of explicit critical path AMI practice guidelines provide a more likely explanation. Future studies by a network of community and university investigators will test whether these findings are true for a broad AMI population and whether similar practice definition and improvement tools are effective for other cardiac problems, including the management of congestive heart failure.

BACKGROUND In animal models, dichloroacetate (DCA) facilitates recovery from severe myocardial ischemia by stimulating glucose oxidation. OBJECTIVE To evaluate the acute efficacy of DCA as a metabolic anti-ischemic intervention in patients with coronary artery disease (CAD) and exercise-induced myocardial ischemia in a clinical trial. METHODS Double-blind, randomized, crossover comparison of single dose (50 mg/kg intravenously) DCA versus placebo on clinical and electrocardiographic variables in seven patients with single vessel CAD and 34 patients with multiple vessel CAD during standard dynamic exercise testing. RESULTS Blood pressure did not differ with placebo or DCA but mean heart rate was higher with DCA at rest (62 versus 59, P < 0.004) and at 5 mins of recovery (78 versus 75, P < 0.02). Exercise duration averaged 538 s with DCA and 534 s with placebo (not significant). Chest pain occurred in 14 patients in both tests, clinical ST depression occurred, in 34 placebo tests and 37 DCA tests (not significant). Body surface potential maps (BSPM) of the decrease in the area under the ST curve from rest to peak exercise averaged -5096 microV's with DCA and -5159 microV's with placebo (not significant). BSPM at 1 and 5 mins postexercise also showed no differences in rate of ST integral recovery. CONCLUSIONS In the transient regional model of human myocardial ischemia induced by dynamic exercise, the acute administration of the pyruvate dehydrogenase agonist DCA was not associated with clinical or electrocardiographic moderation of, nor accelerated recovery from, ischemia. Whether DCA or metabolically similar agents that enhance oxidative metabolism are beneficial in other ischemic settings, such as the no-flow states of acute ST elevation myocardial infarction or angioplasty, requires further systematic evaluation.