- Poster presentation
- Open Access
Early administration of β-blockade in high-risk, acute coronary syndrome patients
© BioMed Central Ltd 2006
- Published: 21 March 2006
- Percutaneous Coronary Intervention
- Acute Coronary Syndrome
- Primary Percutaneous Coronary Intervention
- Acute Coronary Syndrome Patient
- Coronary Care Unit
Acute coronary syndromes represent the life-threatening phase of coronary artery disease. Over two decades ago, two large randomised controlled trials showed a reduction in early mortality when intravenous (i.v.) β-blockade was given acutely to patients presenting with ST elevation myocardial infarction [1, 2]. β-Blockers also limit infarct size, reduce life-threatening arrhythmias, relieve pain, prevent myocardial rupture and reduce reinfarction rates. More recent data suggest that the early administration of β-blockade with thrombolytic therapy or prior to primary percutaneous coronary intervention also has significant benefits. Despite evidence, the use of β-blockade in patients presenting with acute myocardial infarction remains poor and i.v. β-blockade is rarely used.
To assess the use of early (within 24 hours) β-blockade in patients presenting with acute ST elevation myocardial infarction (MI). A prospective audit was carried out on consecutive patients admitted to our coronary care unit over a 6-month period.
In 6 months 87 patients were admitted (males 60, female 27). The average age was 65.5 years. Sixteen per cent of patients (14/87) had had a previous MI and 41% (36/87) had three or more risk factors for coronary artery disease. Presenting ECG, 54% (47/87) of patients had either an anterior (median TnT 7.3 ng/ml) or lateral (TnT 2.43 ng/ml) MI and 46% (40/87) a posterior (TnT 6.11 ng/ml) or inferior MI (TnT 4.24 ng/ml). The majority of patients received reperfusion therapy, 47% (41/87) thrombolysis and 44% (38/87) were treated with primary percutaneous intervention. Nine out of 87 did not receive reperfusion therapy due to late presentation. The mean pulse on admission 75 (± 23) bpm and systolic BP 135 (± 39) mmHg. Only seven patients received intravenous β-blockade within the first 24 hours, with no adverse reactions reported. Twenty-one out of 87 patients were already taking a β-blocker at the time of admission. Fifty-three out of 87 received oral β-blockade within the first 24 hours and 67/87 patients were discharged on β-blockade. The average delay in initiating β-blockade, 8.4 hours from admission. Contraindications to β-blockade existed in 14% (12/87) of patients (5/87 second/ third-degree heart block, 5/87 severe heart failure and 2/87 asthma).
During the acute phase of acute MI, β-blockade is indicated in all patients without an absolute contraindication, and a large evidence base supports their use. Our results have shown that the early (<24 hours) use of β-blockade, and in particular i.v. β-blockade, is low. This may in part be due to clinicians' lack of awareness of the benefits of early i.v. β-blockade, and ongoing education is required.