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Accumulating evidence from clinical trials suggests that a lower (restrictive) hemoglobin threshold (8% g/dL) for red blood cell (RBC) transfusion, compared with a higher (liberal) threshold (≥10 g/dL) is safe. However, in anemic patients with acute myocardial infarction (MI), maintaining a higher hemoglobin level may increase oxygen delivery to vulnerable myocardium resulting in improved clinical outcomes. Conversely, RBC transfusion may result in increased blood viscosity, vascular inflammation, and reduction in available nitric oxide resulting in worse clinical outcomes. We hypothesize that a liberal transfusion strategy would improve clinical outcomes as compared to a more restrictive strategy.We will enroll 3500 patients with acute MI (type 1, 2, 4b or 4c) as defined by the Third Universal Definition of MI and a hemoglobin10 g/dL at 144 centers in the United States, Canada, France, Brazil, New Zealand, and Australia. We randomly assign trial participants to a liberal or restrictive transfusion strategy. Participants assigned to the liberal strategy receive transfusion of RBCs sufficient to raise their hemoglobin to at least 10 g/dL. Participants assigned to the restrictive strategy are permitted to receive transfusion of RBCs if the hemoglobin falls below 8 g/dL or for persistent angina despite medical therapy. We will contact each participant at 30 days to assess clinical outcomes and at 180 days to ascertain vital status. The primary endpoint is a composite of all-cause death or recurrent MI through 30 days following randomization. Secondary endpoints include all-cause mortality at 30 days, recurrent adjudicated MI, and the composite outcome of all-cause mortality, nonfatal recurrent MI, ischemia driven unscheduled coronary revascularization (percutaneous coronary intervention or coronary artery bypass grafting), or readmission to the hospital for ischemic cardiac diagnosis within 30 days. The trial will assess multiple tertiary endpoints.The MINT trial will inform RBC transfusion practice in patients with acute MI.

Medical care in Canadian cardiac units has changed considerably over the past 3 decades in response to an increasingly complex and diverse patient population admitted with acute cardiac pathology. To maintain the highest level of care for these patients, there is a pressing need to evolve traditional coronary care units into contemporary cardiac intensive care units. In this article we aim to highlight the current variations in Canadian units, develop approaches to overcome logistical and infrastructural obstacles, and propose staffing and training recommendations that would allow for the establishment of contemporary cardiac intensive care units.

In hypertensive patients, the development of left ventricular hypertrophy seems to increase the risk of cardiovascular death. Although some antihypertensive agents have been associated with regression in left ventricular hypertrophy, diuretics, the most widely used ones, have not. Indapamide is a new, nonthiazide diuretic and vasodilator. To test its effects on left ventricular hypertrophy, patients with essential hypertension and left ventricular hypertrophy were studied before and at the end of 6 months of therapy with 2.5 mg of indapamide daily. Candidates had to have moderate, uncontrolled essential hypertension with echocardiographically documented left ventricular hypertrophy (left ventricular mass index greater than or equal to 130 gm/m2 for men and greater than or equal to 110 gm/m2 for women). Patients with complicated hypertension or with significant cardiovascular or metabolic diseases were excluded. Patients could remain on antihypertensive drugs other than diuretics, provided doses remained stable for 3 months before entry and there was no know regression of left ventricular hypertrophy. Of 13 patients selected, 2 dropped out. The remaining 11 patients successfully completed 6 months of therapy. The average age was 56 +/- 10 years. Indapamide was associated with a significant reduction of mean systolic blood pressure from 172 to 142 mm Hg (p less than 0.001), diastolic blood pressure from 101 to 83 mm Hg (p less than 0.001), and left ventricular mass index from 146 +/- 22 to 124 +/- 22 gm/m2 (mean +/- SD) (p less than 0.003).(ABSTRACT TRUNCATED AT 250 WORDS)

Radionuclide left ventricular ejection fraction, end-diastolic volume, and exercise capacity were determined in 34 selected patients who survived a first Q wave anterior infarction. Patients were included in the study if they had no subsequent cardiac events (unstable angina or myocardial infarction) during the average follow-up period of 47 months (range = 36 to 70 months); none was treated with thrombolysis, coronary angioplasty, or bypass grafting. Overall, mean left ventricular ejection fraction increased from 28 +/- 10% 1 month after infarction to 33 +/- 10% at 3 years (p less than 0.01); mean end-diastolic volume decreased from 217 +/- 99 ml to 171 +/- 80 ml (p less than 0.002). Stepwise improvement in left ventricular ejection fraction occurred in 15 of these patients (group B) and was associated with a significant increase in exercise capacity. Mean ejection fraction in group B was 26 +/- 7% at 1 month and 41 +/- 10% at 3 years (p less than 0.001). In all of these patients there was improved regional wall motion in the noninfarct zone, whereas five patients also showed improvement in the infarct zone. The results indicate a progressive improvement in left ventricular function that occurs over time in some patients after first Q wave anterior infarction, independent of intervention.