Current Controlled Trials in Cardiovascular Medicine最新文献

BACKGROUND: A large body of data derived from animal, epidemiological and clinical studies indicate that n-3 polyunsaturated fatty acids have a favourable effect on the prognosis of patients with cardiovascular disease in general, and on reducing sudden death in particular.Depressed heart rate variability (HRV), an indicator of impairment of the autonomic nervous system, has been shown to be a powerful predictor of subsequent mortality in patients surviving an acute myocardial infarction. A multitude of studies have demonstrated this strong association, suggesting that the imbalance in the sympathic/parasympathetic system may facilitate emergence of ventricular arrhythmias.Heart rate variability parameters will be assessed in the present study, with the primary objective of evaluating the possible superiority of Omacor (a highly refined, concentrated omega-3 fatty acid) versus placebo in improving HRV from baseline to endpoint in patients with recent uncomplicated myocardial infarction. Both groups will receive optimal conventional treatment.The study will also explore and quantify improvement in time domain HRV indices and will assess the safety of administering Omacor to optimally treated post-infarction patients (conventional treatment). METHODS: This multi-centre study will evaluate the effect of Omacor 1 g, o.d. on time-domain HRV parameters in comparison to placebo o.d. in patients with recent uncomplicated transmural myocardial infarction.Patients will be screened during the first few days after the acute event as appropriate for the patient's condition, and after obtaining informed consent. Based on inclusion/exclusion criteria, a first 24-hour Holter recording will be performed. Two to five days later, screened patients still eligible for the study will undergo a second 24-hour Holter recording. After the second Holter recording, all patients will be randomly allocated to treatment with Omacor 1 g, o.d. or placebo o.d.One hundred patients will be followed in double-blind fashion for a six-month period after randomization. Visits, including 24-hour Holter recording and assessment of adverse events, will take place at one-month intervals +/- five days after randomization, i.e., six times in all.

BACKGROUND: Currently, there are a lack of investigations that have examined the effect of participating in a comprehensive cardiac rehabilitation program on quality of life and physiological measures in women of different ages. The purpose of this investigation was to examine the effect of participating in a comprehensive cardiac rehabilitation program on quality of life, exercise tolerance, blood pressure and lipids in women between 33 and 82 years of age. METHODS: The 126 women participated in a 14-week cardiac rehabilitation program that consisted of 7 weeks of formal supervised exercise training and 7 weeks of unsupervised exercise and lifestyle modification. Physiologic and quality of life outcome measures obtained at the outset and after 14 weeks included: 1) exercise treadmill time; 2) resting and peak systolic and diastolic blood pressure; 3) total cholesterol, low-density lipoprotein cholesterol, high density lipoprotein cholesterol and Triglycerides; 4) Cardiac Quality of Life Index questionnaire. RESULTS: Significant improvements were found in the following quality of life measures after participating in the cardiac rehabilitation program: physical well being, psychosocial, worry, nutrition and symptoms. No significant differences were seen for any QOL variable between the different age groups. Significant improvements were seen in exercise tolerance (+21%) and high density lipoprotein (+5%). CONCLUSION: Cardiac rehabilitation may play an important role in improving quality of life, exercise tolerance and high density lipoprotein cholesterol levels in younger and older women with underlying cardiovascular disease.

BACKGROUND: The Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) is a randomized, double-blind, active-controlled trial designed to compare the rate of coronary heart disease events in high-risk hypertensive participants initially randomized to a diuretic (chlorthalidone) versus each of three alternative antihypertensive drugs: alpha-adrenergic blocker (doxazosin), ACE-inhibitor (lisinopril), and calcium-channel blocker (amlodipine). Combined cardiovascular disease risk was significantly increased in the doxazosin arm compared to the chlorthalidone arm (RR 1.25; 95% CI, 1.17-1.33; P <.001), with a doubling of heart failure (fatal, hospitalized, or non-hospitalized but treated) (RR 2.04; 95% CI, 1.79-2.32; P <.001). Questions about heart failure diagnostic criteria led to steps to validate these events further. METHODS AND RESULTS: Baseline characteristics (age, race, sex, blood pressure) did not differ significantly between treatment groups (P <.05) for participants with heart failure events. Post-event pharmacologic management was similar in both groups and generally conformed to accepted heart failure therapy. Central review of a small sample of cases showed high adherence to ALLHAT heart failure criteria. Of 105 participants with quantitative ejection fraction measurements provided, (67% by echocardiogram, 31% by catheterization), 29/46 (63%) from the chlorthalidone group and 41/59 (70%) from the doxazosin group were at or below 40%. Two-year heart failure case-fatalities (22% and 19% in the doxazosin and chlorthalidone groups, respectively) were as expected and did not differ significantly (RR 0.96; 95% CI, 0.67-1.38; P = 0.83). CONCLUSION: Results of the validation process supported findings of increased heart failure in the ALLHAT doxazosin treatment arm compared to the chlorthalidone treatment arm.

Background: Cardiac rehabilitation programs (CRP) represent comprehensive interventions that are typically limited to four months. Following completion of CRP, it appears that risk factors and lifestyle behaviours may deteriorate. The Extensive Lifestyle Management Intervention (ELMI) Following Cardiac Rehabilitation trial will investigate the benefits of a randomized intervention to prevent these adverse changes.

Methods: Patients with ischemic heart disease (IHD) were randomized following a standard CRP to the ELMI or to usual care. The ELMI program is a case-managed intervention aimed at individualizing risk factor and lifestyle management based on current treatment guidelines. The program consists of cardiac rehabilitation sessions, telephone follow-up and risk factor and lifestyle counselling sessions. Health professionals work with participants using behavioural counselling and communications with participants' family physicians. Usual care participants return to their family physicians' care, and come to the study clinic only to undergo annual outcomes assessment. The primary outcome is change in IHD global risk after four years. Secondary outcomes include combined cardiovascular events, health care utilization, lifestyle adherence, quality of life and risk factors.

Results: Over 28 months, 302 men and women were randomized. This represented 29% of the total population screened. The average age of study participants is 64 years, 18% are women, 53% have had a previous myocardial infarction, 73% have undergone previous revascularization and 20% have diabetes mellitus. Ischemic heart disease risk factors for the entire cohort improved significantly after subjects had gone through previous CRPs. Baseline risk factors, lifestyle behaviours and medications were similar between the groups.

Conclusions: This study population is representative of patients completing a standard CRP. Results of the ELMI trial will provide valuable information for the future design of CRPs.

The Myocardial Ischemia Reduction with Aggressive Cholesterol Lowering (MIRACL) study was the first trial to assess whether statins might be of clinical benefit in those with recently unstable coronary disease. MIRACL found that high-dose atorvastatin was safe and reduced the incidence of the composite endpoint, death, non-fatal myocardial infarction, resuscitated sudden cardiac death or emergent rehospitalization for recurrent ischemia at 16 weeks when compared with placebo. Despite a number of important study limitations, MIRACL's findings and the prior observation that inpatient initiation of lipid-lowering therapy is associated with higher rates of subsequent utilization, suggest that it is prudent to begin statin therapy when patients present with an acute coronary syndrome.