Study of STEMI Protocol Shows Sustained Success in Closing the Gender Care Gap

The answer to closing the gender gap in the management of ST-elevation myocardial infarction (STEMI) may lie in adopting a comprehensive STEMI protocol, suggests a new analysis out of Cleveland Clinic.

The observational cohort study, published online in European Heart Journal Open, found reduced sex disparities in various STEMI outcomes and quality measures through five years after implementation of Cleveland Clinic’s comprehensive protocol for STEMI management compared with the period before implementation.

“Sex disparities in STEMI care and outcomes have been widely reported, prompting the American Heart Association and the European Society of Cardiology to identify their reduction as a public health priority,” says the study’s corresponding author, Umesh Khot, MD, Head of Regional Cardiovascular Medicine at Cleveland Clinic. “Our study is the first to show how a systems approach using a comprehensive STEMI protocol can reduce mortality in women and largely eliminate disparities in death and other cardiovascular outcomes over a five-year period.”

Building on promising two-year results

Considerable literature evidence has demonstrated that, compared with their male counterparts, women with STEMI receive guideline-directed medical therapy less often and have a significantly longer average door-to-balloon time. These care disparities have resulted in significantly higher rates of in-hospital adverse events, new-onset heart failure and mortality from STEMI among women compared with men.

In July 2014, Cleveland Clinic adopted a four-step protocol designed to reduce variability in STEMI management across its facilities in Northeast Ohio. Soon afterward, it noticed that care metrics and outcomes improved across the board — but were particularly improved among female patients, thereby shrinking the traditional sex-based STEMI care gap.

Those results, published in the Journal of the American College of Cardiology (2018;71:2122-2132), were attributed to the new four-step protocol, which (as detailed in a prior Consult QD article) involved the following:

• Standardizing criteria by which emergency department physicians can activate the cath lab
• Using a “STEMI safe handoff checklist” defining roles of all caregivers involved
• Immediately transferring patients to an available cath lab at all times to avoid delays
• Moving to a “radial artery first” approach for vascular access in primary percutaneous coronary intervention (PCI) for all appropriate candidates

“Two years after implementing this comprehensive STEMI protocol, we observed improvements in use of guideline-directed therapy, door-to-balloon time and 30-day mortality in both sexes, but the improvements were especially pronounced in women, to the point that there were no longer statistically significant differences between the sexes,” says co-investigator Samir Kapadia, MD, Chair of Cardiovascular Medicine at Cleveland Clinic. “However, it was unclear whether these results could be consistently sustained over the long term.”

Study design and results

To explore that question, the researchers revisited results five years after implementation of the STEMI protocol. Their pre/post analysis assessed the management and outcomes of 1,833 consecutive patients with STEMI — 723 in the 3.5 years prior to protocol implementation (control group) and 1,110 in the five years following protocol implementation (protocol group). Women made up a similar share of the sample in the control and protocol groups (32.2% and 32.5%, respectively), and differences between men and women were consistent across the two groups.

The table below presents differences in process metrics and outcomes between male and female patients before and after the STEMI protocol. Prior to protocol implementation, results significantly favored males over females on all measures except for use of trans-radial PCI. In contrast, after protocol adoption, differences between the sexes were reduced to nonsignificant levels on all measures except for use of trans-radial PCI, which favored men, and net adverse clinical events, which trended toward favoring men. The latter outcome was largely attributable to a significantly higher rate of bleeding in female patients.

Putting the findings in context

“We have shown that door-to-balloon times and use of guideline-directed medical therapy were similar between the sexes for five years following adoption of our STEMI protocol,” says study co-author Grant Reed, MD, MSc, Director of Cleveland Clinic’s STEMI Program. “This corresponded to elimination of significant disparities in mortality and major adverse cardiac and cerebrovascular events between the sexes, although an excess of bleeding in women persisted. Use of trans-radial PCI also increased dramatically across the board with protocol implementation, although use in women still falls short of that in men.”

The authors note that their STEMI protocol differs fundamentally from other STEMI protocols that focus strictly on door-to-balloon time. “The Cleveland Clinic protocol is unique in its focus on early antithrombotic and antiplatelet drugs before PCI,” explains Dr. Kapadia. “Inappropriate variability in this area was minimized by our standardized STEMI checklist in the emergency department.”

“Maintaining early quality gains over the long term is a perennial challenge in hospital quality improvement efforts,” notes Dr. Khot. “That’s why these five-year results are reassuring.” He and his co-authors identify four reasons for the protocol’s enduring success:

• Oversight of the STEMI program, including protocol adherence, by an interdisciplinary team comprising cardiologists, cardiology fellows, emergency physicians, nurses and critical care transport staff
• Monthly STEMI committee meetings to review cases and discuss new developments
• Orientation of all new trainees to the STEMI system workflow and team expectations
• Constructive and nonpunitive sharing of feedback on performance to continually improve STEMI care

“Although every health system is different,” Dr. Khot concludes, “we hope the sustained success of this protocol may serve as a model for others looking to improve their STEMI processes and outcomes and make substantial progress in closing the gender gap in STEMI care.”