Few studies have reported population-based information on the treatment trends and outcomes of patients who have had an acute myocardial infarction (AMI). We therefore examined patterns of care and outcomes for AMI patients in Quebec, Canada, between 1988 and 1995.
Longitudinal data files of hospital admissions in Quebec (Med-Echo database) and inpatient and outpatient services (Régie de l'Assurance Maladie du Québec database) were used to construct cohorts of all AMI patients in the province between 1988 and 1995. Temporal trends in the use of cardiac procedures after an AMI, discharge prescriptions and mortality rates were examined.
Between 1988 and 1995 the age- and sex-adjusted rates of AMI in the Quebec population declined (148 per 100,000 in 1988 to 137 per 100,000 in 1995). The use of intensive cardiac procedures increased in the same period; the 1-year cumulative incidence rate of catheterization increased from 28% in 1988 to 31% in 1994, that of angioplasty rose from 8% to 15% and that of coronary artery bypass surgery from 6% to 8%. Prescriptions for ASA, beta-blockers, lipid-lowering agents and angiotensin-converting enzyme inhibitors increased, and prescriptions for nitrates and calcium antagonists decreased. These temporal changes were paralleled by a decrease in mortality rates post-AMI. All-cause 1-year cumulative incidence mortality rates decreased from 23% in 1988 to 19% in 1994.
The decrease in AMI-related mortality in Quebec between 1988 and 1995 may be linked to changes in treatment strategies (i.e., increased use of cardiac surgical procedures and medications shown to increase survival).
Cites: N Engl J Med. 1994 Oct 27;331(17):1130-57935638
Cites: J Am Coll Cardiol. 1995 May;25(6):1327-327722129
Cites: JAMA. 1995 May 24-31;273(20):1586-917745771
Cites: Med Care. 1995 Jun;33(6):598-6107760576
Cites: N Engl J Med. 1995 Aug 31;333(9):565-727623907
Cites: N Engl J Med. 1995 Aug 31;333(9):573-87623908
Cites: J Am Coll Cardiol. 1995 Nov 1;26(5):1115-207594019
Cites: Am Heart J. 1996 May;131(5):872-88615304
Cites: N Engl J Med. 1996 Oct 17;335(16):1198-2058815943
Cites: N Engl J Med. 1997 May 22;336(21):1500-59154770
Cites: Circulation. 1998 Jul 7;98(1):1-59665051
Cites: J Am Coll Cardiol. 1998 Aug;32(2):360-79708461
Cites: JAMA. 1998 Aug 19;280(7):623-99718054
Cites: CMAJ. 1999 Nov 16;161(10):1257-6110584086
Cites: N Engl J Med. 1992 Jul 23;327(4):241-71535419
Cites: N Engl J Med. 1993 Mar 18;328(11):779-848123063
Cites: Arch Intern Med. 1994 May 23;154(10):1090-68185422
Comment In: CMAJ. 2001 Feb 6;164(3):323; author reply 32411232129
Surgical repair of abdominal aortic aneurysms (AAA) is increasingly being performed, but little is known about the correlates of in-hospital cost associated with this procedure.
Baseline clinical characteristics, in-hospital outcomes, and total in-hospital costs were examined among a retrospective cohort of 71 patients who underwent AAA repair. Median age was 68 years, and 75% of the patients were men. High-risk characteristics for perioperative complications were common and included hypertension (73%), documented coronary artery disease (66%), smoking (60%), previous myocardial infarction (47%), history of congestive heart failure (12%), urgent or emergent AAA repair (16%), and diabetes mellitus (11%). Perioperative complications included congestive heart failure (13%), myocardial infarction (11 %), and death (1 %). Median length of stay in the surgical intensive care unit (SICU) was 2 days (range 0 to 28), and median in-hospital stay was 9 days (range 5 to 39). In-hospital cost for the 71 patients ranged from $13,766 to $82,435 (mean $25,931, median $21,633). Univariate and multiple linear regression analyses demonstrated that among the potential correlates investigated, number of SICU days (P= .007) and total length of stay (P
Many physicians are not adhering to the recommendations found in evidence-based guidelines for the treatment of acute myocardial infarction (AMI). Physicians who practise in tertiary care settings may show better adherence to guideline recommendations than physicians who practise in other settings.
To determine whether there is an association between the practice setting of admission for AMI and discharge prescriptions for cardiac drugs recommended in evidence-based guidelines.
Discharge prescription data from a prospective cohort of patients with AMI admitted at five tertiary care (n=250) and five community hospitals (n=331) in Quebec from December 1996 to November 1998 were examined.
The proportions of patients who were prescribed recommended drugs at tertiary care hospitals compared with those at community hospitals were as follows: beta-blockers (78% versus 74%, respectively; 95% CI around the difference - 4% to 11%), lipid-lowering drugs (45% versus 39%, respectively; 95% CI - 2% to 15%) and angiotensin-converting enzyme (ACE) inhibitors (44% versus 57%, respectively; 95% CI - 22% to - 5%). In adjusted analyses, practice setting was not associated with the prescription of beta-blockers (odds ratio [OR] for tertiary care 1.36; 95% CI 0.82 to 2.24) or lipid-lowering drugs (OR for tertiary care 1.06; 95% CI 0.67 to 1.68). However, tertiary care admission reduced the likelihood of ACE inhibitor prescription (OR 0.50; 95% CI 0.32 to 0.77). This association may have been due to the increased likelihood of ACE inhibitor prescription for patients with hypertension at community hospitals (OR 2.13; 95% CI 1.23 to 3.67). The results also showed that older patients were less likely to be prescribed beta-blockers or lipid-lowering drugs, women were less likely to be prescribed beta-blockers and patients with diabetes mellitus were less likely to be prescribed lipid-lowering drugs (OR 0.45; 95% CI 0.23 to 0.89).
No strong association was found between the practice setting of admission for AMI and discharge prescriptions for cardiac drugs recommended in evidence-based guidelines. Prescription rates for recommended drugs were high, yet results suggest that there is room for improvement with regard to patients with diabetes, women and older patients.
Authorities recommend various strategies to identify restenosis in patients who have undergone percutaneous transluminal coronary angioplasty (PTCA). Some authorities recommend a routine functional testing strategy, while others recommend a clinically driven strategy.
To examine the patterns of use of post-PTCA functional testing, 89 directors of cardiac catheterization laboratories in Canada and the United States were surveyed.
Demographic characteristics of the Canadian and American respondents were similar, including median age (43 and 45 years, respectively) and median number of PTCAs performed each year (200 each). Canadians were more likely to employ a routine functional testing strategy than Americans (62% versus 38%), while Americans were more likely to employ stress imaging studies than Canadians (49% versus 35%). Overall, close to half (44%) of all the cardiologists employed a routine functional testing strategy. Physicians who employed a routine functional testing strategy performed the first functional test a median of three months after PTCA and the second a median of six months after PTCA. Both Canadian and American cardiologists tended to underestimate the incidence of restenosis after PTCA (33% without a stent and 18% with a stent) and to overestimate the sensitivity of exercise treadmill testing for the detection of restenosis (63%).
The use of functional testing after PTCA varies widely. Canadian cardiologists are more likely to employ a routine functional testing strategy than American cardiologists. Close to half of the cardiologists surveyed employed a routine functional testing strategy. These results indicate that there is little consensus regarding the use of functional testing after PTCA.
A link between Mg deficiency and sudden death is suggested by a substantial number of studies published over the past three decades. Data come from epidemiologic, autopsy, clinical, and animal studies. They suggest that: (1) Sudden death is common in areas where community water supplies are Mg-deficient. (2) Myocardial Mg content is low in people who die of sudden death. (3) Cardiac arrhythmias and coronary artery vasospasm can be caused by Mg deficiency and (4) Intravenous Mg reduces the risk of arrhythmia and death immediately after acute myocardial infarction. Because of these data, Mg supplementation has been proposed as a possible method of reducing the risk of sudden death. Suggested ways of supplementing Mg include public education to change dietary habits, addition of Mg to community water supplies, fortification of foods, and oral supplementation. Despite the substantial number of studies linking Mg deficiency with sudden death, no prospective studies have yet investigated whether large-scale Mg supplementation is useful for the primary prevention of sudden death.
Antiarrhythmic drug prophylaxis in patients with atrial fibrillation (AF) is associated with a high incidence of arrhythmic recurrence. Uncontrolled studies have suggested that low-dose amiodarone may be superior in terms of efficacy to other antiarrhythmic drugs while having an acceptable side effect profile. The Canadian Trial of Atrial Fibrillation (CTAF) is a 25-center study sponsored by the Medical Research Council of Canada to determine the best treatment strategy to maintain sinus rhythm in patients with persistent or paroxysmal AF. Recruitment began in November 1996 and will continue for 1.5 years. Patients are randomized to receive either low-dose amiodarone or conventional antiarrhythmic drug therapy. Patients assigned to the amiodarone group will receive an oral loading regimen of 10 mg/kg/day during a minimum 14-day period. Patients assigned to conventional antiarrhythmic therapy will receive 1 of 2 agents commonly used in AF prophylaxis: sotalol or propafenone. Drug selection and loading, and electrical cardioversion, if necessary, will be performed within 21 days of randomization. The long-term maintenance dose of amiodarone is 200 mg/day. We have planned a minimum follow-up period of 1 year. The primary end point is the time to the first relapse of AF. Data will be analyzed on an intention-to-treat basis. Secondary outcomes are medication toxicity, mortality, major clinical events, costs of each approach, and quality of life. For the purpose of sample size calculations, it is anticipated that recurrence of AF at 1 year will occur in 50% of patients on conventional treatment compared with 35% in those receiving amiodarone. In order to have an 80% power and a 2-tailed type I error of 0.05, assuming a 15% loss to follow-up rate, a total sample size of 400 patients will be required. A pilot study done at the Montreal Heart Institute has shown that the research protocol is feasible.