Volume 190 - Issue 3
Invasive management and late clinical outcomes in contemporary Australian management of acute coronary syndromes: observations from the ACACIA registry
Authors: Leigh D Kinsman, Julie Redfern and Tom G Briffa
Med J Aust 2009; 190 (3): 162. || doi: 10.5694/j.1326-5377.2009.tb02324.x
Published online: 2 February 2009
Published online: 2 February 2009
To the Editor: The work presented by Chew and colleagues in setting up and using the Acute Coronary Syndrome Prospective Audit (ACACIA) is an important and influential initiative.1 It has the potential to provide a strong evidence base for the design and delivery of cardiac services in Australia.
Their article and the accompanying editorial by Scott2 highlighted the difficulty in determining treatment benefit from uncontrolled observational studies. Among the unreported and possibly significant confounders underpinning the association between acute invasive care and the 47% improved 12-month survival in patients treated for acute coronary syndrome is participation in post-event secondary-prevention cardiac rehabilitation. A contemporary systematic review of randomised controlled trials of cardiac rehabilitation reported a significant relative risk reduction in all-cause mortality of 20% (95% CI, 7%–32%) over a median follow-up of 12 months.3
Despite this evidence and the long-term policy of the World Health Organization that cardiac rehabilitation should be available to all patients with cardiovascular disease,4 this secondary-prevention intervention is largely underused, and those who do attend are generally at lower risk of recurrent coronary events than those who do not.5 Further, secondary-prevention cardiac-rehabilitation programs are cost-effective relative to other coronary interventions6 and, along with proven cardioprotective pharmacotherapy and acute invasive care, should be given priority as part of an optimal treatment and management strategy for secondary prevention.
The completion of cardiac rehabilitation or other forms of secondary prevention by ACACIA patients may have favourably impacted upon the marked improvement in 12-month survival seen in the ACACIA cohort. Chew and colleagues identified the fact that patients who underwent invasive therapies were also more likely to be treated according to best-practice guidelines.1 It may be that this same group were also more likely to be referred to cardiac-rehabilitation and secondary-prevention programs. It would be of great interest to know if attendance in cardiac-rehabilitation and secondary-prevention programs was recorded in the ACACIA registry and, if so, why those results were not incorporated.
References
- Chew DP, Amerena JV, Coverdale SG, et al, on behalf of the ACACIA investigators. Invasive management and late clinical outcomes in contemporary Australian management of acute coronary syndromes: observations from the ACACIA registry. Med J Aust 2008; 188: 691-697. <eMJA full text>
- Scott IA. Acute coronary syndromes: exploring the best way forward in optimising care [editorial]. Med J Aust 2008; 188: 686-687. <eMJA full text>
- Taylor RS, Brown A, Ebrahim S, et al. Exercise-based rehabilitation for patients with coronary heart disease: systematic review and meta-analysis of randomized controlled trials. Am J Med 2004; 116: 682-692. 0_CBBGDBIJ
- World Health Organization. Rehabilitation after cardiovascular diseases, with special emphasis on developing countries. Report of a WHO expert committee. WHO technical report series 831. Geneva: WHO, 1993. http://whqlibdoc.who.int/trs/WHO_TRS_831.pdf (accessed Jun 2008).
- Redfern J, Ellis ER, Briffa T, Freedman SB. High risk-factor level and low risk-factor knowledge in patients not accessing cardiac rehabilitation after acute coronary syndrome. Med J Aust 2007; 186: 21-25. <eMJA full text>
- Briffa TG, Eckermann SD, Griffiths AD, et al. Cost-effectiveness of rehabilitation after an acute coronary event: a randomised controlled trial. Med J Aust 2005; 183: 450-455. <eMJA full text>