The study demonstrates the national progress in the treatment of patients with STEMI who undergo primary PCI. Median patient D2B times decreased substantially from 96 minutes to 64 minutes, a drop of 32 minutes, over the 6 years ending in mid-2010, representing more than a 30% relative decline. This improvement, experienced across the country and across different types of hospitals, represents a remarkable elevation in practice that was achieved over a relatively short period of time and in the absence of financial incentive. The accomplishment is truly a tribute to interventional cardiologists, emergency medicine physicians, nurses, technologists, and other team members nationwide who were dedicated to improving D2B times.
The perspective on D2B times changed dramatically over this period. The 2004 STEMI guidelines recommended that patients be treated with primary PCI within 90±30 minutes.18
The caveat of the additional 30 minutes was included as a compromise in response to controversy about whether it was possible for hospitals to routinely treat patients with STEMI within 90 minutes. The publication of the 2004 guidelines was followed by a shift toward the 90-minute standard. Nallamothu and colleagues published a study based on trials of the relationship between D2B time and the advantage of primary PCI over fibrinolytic therapy.1
They found that if primary PCI was delayed more than an hour beyond the time that fibrinolytic therapy could be provided, the advantage was lost. Thus, if fibrinolytic therapy was recommended to be given within 30 minutes, then the provision of primary PCI within 90 minutes was supported by evidence from the trials. In the guideline update published in 2007, the additional 30 minutes was removed, altering the recommendation for D2B time to <90 minutes.6
The CMS measure, which initially reported the percent of patients treated within 120 minutes, was subsequently reduced to 90 minutes in 2006 to align the performance measure with the new guideline recommendation.17
The improvement in D2B times that we observed cannot be definitively attributed to any single action, but many activities likely contributed. During this period, multiple national efforts focused attention on timeliness of D2B and supported quality improvement. Published articles that revealed gaps in care and indicated strategies that were associated with faster times contributed to clinical changes in performance. A study sponsored by the National Institutes of Health used a mixed methods approach to examine exceptional performers and then test hypotheses that derived from their experience.7-10,19
CMS developed contracts with Quality Improvement Organizations that contributed to the increasing focus on improving various aspects of AMI care, including D2B times. Hospital groups and consortia focused on improving D2B times. The performance of the nation’s hospitals in treating patients with STEMI was further highlighted by the release of the publicly reported D2B time measures by CMS, and the D2B Alliance and Mission: Lifeline, national campaigns by the ACC and the AHA, enlisted clinicians and hospitals in a broadbased effort to reduce delays.12-13
Improvement in D2B times demonstrates the way that emerging science about how to improve care can be rapidly integrated into practice. The ACC campaign was launched simultaneously with the publication of a paper in the New England Journal of Medicine
that described strategies associated with faster times.9
The ACC campaign promoted the adoption of such strategies, which were shown to be underutilized nationally. Recent reports demonstrated the marked integration of these strategies into practice that occurred during the period of the campaign.14
Moreover, a recent qualitative study showed that the credibility of the campaign was related to the strength of the science and the clarity of the recommendations.20
Despite the recent gains, additional opportunities for improvement in D2B times remain. The most outstanding institutions are now regularly achieving exceptional times of approximately 60 minutes through strategies including coordination with Emergency Medical Services and the collection and dissemination of a pre-hospital electrocardiogram.21-23
This level of performance may become the new standard.
Another opportunity for improvement is related to the care of transfer patients. Prior studies have shown that many patients who are transferred from a hospital without PCI capability to a PCI-capable institution experience long delays in treatment.24-25
To address this concern, CMS is collecting a measure, with potential to be publicly reported, which assesses the time required to transfer such patients.17
More importantly, current research shows that these times can be reduced through greater coordination between hospitals.26-27
A limitation of this assessment is the evolution of the measure over the study period, with modifications primarily related to the exclusion criteria. The most notable change occurred in 2006 and allowed hospitals to exclude patients based on the judgment that a D2B time >90 minutes was the result of a delay incurred by patient preference or clinical condition. Subsequent changes included minor alterations in the codes or slight expansions in the exclusion criteria. However, the dramatic decline in D2B times that was observed over the study period is unlikely to have resulted from changes in the measure. Moreover, the greatest decline occurred between 2006 and 2007, a period corresponding to the initiation of national campaigns to improve D2B times. Finally, our results are aligned with those of registries that documented trends in D2B times and applied consistent criteria over time.
In conclusion, we document remarkable improvement in D2B times from 2005 through 2010. The improvement demonstrates the results that can be produced by collaboration between health care professionals, hospitals, federal research agencies and national organizations interested in patient care toward the achievement of a shared goal. The focus on improving the way in which care is delivered - improving the systems - has yielded more timely care for patients and serves as a template for similar contemporary and future efforts in areas such as readmission.