Door-to-balloon delays with PCI in acute myocardial infarction

Guidelines for therapy of ST-segment-elevation acute myocardial infarction in patients presenting to Partners Healthcare system hospital emergency departments

A major focus for individuals and organizations that study the quality of cardiovascular care is the timeliness of treatment for those patients who suffer an acute ST-elevation myocardial infarction (STEMI). We sought to develop guidelines that would inform the development and management of a more standardized approach to the treatment of STEMI within the 5 acute care hospitals that make up the Partners Healthcare acute care hospital network. In recent years much has been learned about how to deliver timely reperfusion therapy in STEMI and how to assess its outcome. As a component of the organization's mandate to promote the uniform high quality of care throughout the system, our group began studying the many aspects of the current treatment of STEMI within the system, we reviewed, summarized and debated the relevant literature, studied best practices and made recommendations for a system-wide approach to this problem. Our methods have included literature review, consultation with local and national experts, site visits throughout the system, web-based surveys of current attitudes within the system, interviews with stakeholders and consensus-development conferences. The result was not only the development of the following guidelines for therapy, but also an ongoing commitment to share patient-level data and outcomes for continuous quality assessment and improvement.

Primary angioplasty in acute myocardial infarction: Hypothetical estimate of superiority over aspirin or untreated controls

BACKGROUND

Primary percutaneous transluminal coronary angioplasty (PTCA) in the setting of ST-segment-elevation myocardial infarction has been compared with intravenous thrombolysis, but its effects versus no treatment are not known. Knowledge of the effects of PTCA in this setting is useful as a substantial minority of patients do not receive thrombolysis because of contraindications.

METHODS

A hypothetical primary PTCA versus placebo/control odds ratio was computed using a recently described statistical technique that employed the logarithm of the odds ratios of the pooled results of meta-analyses of PTCA versus thrombolysis and thrombolysis versus placebo or controlled trials.

RESULTS

Using data from 30 trials, the synthesized odds ratio for mortality for primary PTCA versus placebo/untreated controls is 0.56 (95% confidence interval [CI]: 0.46 to 0.68; P <0.00001), consistent with a 44% reduction. Primary PTCA and aspirin reduces mortality by 69% versus no aspirin (OR = 0.31; 95% CI: 0.21 to 0.45; P <0.00001). In a high-risk group of otherwise eligible patients with thrombolysis contraindications, the absolute benefit is estimated as 93 per 1000 treated (95% CI: 53 to 132 per 1000 treated). The risk of stroke is reduced with primary PTCA (OR = 0.46; 95% CI: 0.30 to 0.71; P = 0.0004).

CONCLUSION

In this setting, primary PTCA would hypothetically reduce the short-term risk of death by 44%. Despite the use of aggressive antithrombotic regimens, the risk of stroke would also be reduced substantially with primary PTCA.