Article Text
PDF
Statistics from Altmetric.com
Report by Katrina Richell-Herren; Search checked by Kevin Mackway-Jones
Clinical scenario
A 45 year old man attends the emergency department with 30 minutes of chest pain. An ECG shows ST segment depression in the inferior leads. You wonder whether he should be treated with low molecular weight heparin (LMWH) or a glycoprotein IIa/IIIb complex inhibitor.
Three part question
In [a patients with acute myocardial ischaemia] is [a low molecular weight heparin better than a platelet glycoprotein IIb/IIIa complex inhibitor] at [reducing morbidity and mortality]?
Search strategy
Medline 1966 to 10/99 using the OVID interface. [{exp angina, unstable OR unstable angina.mp OR exp myocardial ischemia OR myocardial ischemia$.mp OR myocardial ischaemia.mp} AND ({exp heparin OR exp heparin, low-molecular-weight OR heparin$.mp OR LMWH$.mp} AND {exp platelet aggregation inhibitors OR exp platelet glycoprotein gpiib-iiia complex OR tirofiban$.mp})] AND maximally sensitive RCT filter LIMIT to human AND english.
Search outcome
Altogether 324 papers were found of which 318 were irrelevant or of insufficient quality for inclusion. The six remaining papers, which refer to five studies, are shown in table 4.
Comment
There is no trial that directly compares LMWHs with platelet glycoprotein IIb/IIIa complex inhibitors. Both treatments appear to be better than no treatment. The evidence that enoxaparin is better than unfractionated heparin is compelling (for unstable angina odds ratios 0.81, 95% confidence interval 0.68 to 0.96), while that for tirofiban is less so. Even more work is required in this area.
Clinical bottom line
All patients with unstable angina should receive LMWHs in preference to unfractionated heparin. The case for the use of platelet glycoprotein IIb/IIIa complex inhibitors in preference to LMWHs has not been established.
Acknowledgments
The BMA library supplied the papers.
Report by Katrina Richell-Herren; Search checked by Kevin Mackway-Jones