Progress in cardiovascular diseases
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Prog Cardiovasc Dis · Jan 2000
ReviewThe emerging role of low-molecular-weight heparin in cardiovascular medicine.
Although unfractionated heparin is widely used in the treatment of acute coronary syndromes, it has several pharmacokinetic, biophysical, and biological limitations. The practical advantages and success of low-molecular-weight heparin administered subcutaneously without laboratory monitoring for the treatment of venous thromboembolism have prompted a number of randomized studies investigating the efficacy and safety of these agents in patients with acute coronary syndromes. This article will review the limitations of unfractionated heparin and the mechanisms by which low-molecular-weight heparin overcomes these limitations, as well as the results of recent trials involving low-molecular-weight heparin in the management of patients with acute coronary syndromes.
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Prog Cardiovasc Dis · Jan 2000
ReviewDetection of pulmonary embolism by D-dimer assay, spiral computed tomography, and magnetic resonance imaging.
Pulmonary embolism (PE) remains difficult to diagnose. Ventilation perfusion lung scan, the standard diagnostic test for PE, has poor overall sensitivity. The gold standard examination, pulmonary angiography, is invasive and has some risk, making clinicians reluctant to refer patients. ⋯ MRI is also useful for imaging the pulmonary arterial vasculature, but remains experimental. Although a more accurate assessment of the sensitivity of these new modalities will need to wait until a large angiographically controlled study, such as the planned PIOPED II, can be done, D-Dimer assay and spiral CT are often useful in the detection of pulmonary embolism. The authors make recommendations for their use in a diagnostic algorithm, as alternatives to the standard ventilation perfusion lung scan.