STEMI Patients Transferred for Primary PCI Show More Medication Errors

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Patients with ST-segment elevation myocardial infarction (STEMI) who are transferred for primary percutaneous coronary intervention (PCI) in community practice are at higher risk than nontransfer patients for delayed or excessively dosed antithrombotic therapy, highlighting an important area for improving appropriate use of these adjunctive therapies, according to a study appearing online March 17, 2014, ahead of print in the American Heart Journal.

Researchers led by Tracy Y. Wang, MD, MHS, of the Duke Clinical Research Institute (Durham, NC), gauged antiplatelet and anticoagulant therapy use in 64,130 STEMI patients who were (n = 16,801) or were not (n = 47,329) transferred for primary PCI at 441 Acute Coronary Treatment and Intervention Outcomes Network Registry—Get With The Guidelines hospitals from 2007 to 2010. Transfer patients were more likely to receive antiplatelet and anticoagulant therapies prior to catheterization, with the exception of bivalirudin (table 1).

Table 1. Pre-Catheterization Medication Use in Transfer vs Nontransfer Patients

Use Prior to Cath



P Value

Adjusted OR (95% CI)




< 0.001

1.16 (1.06-1.28)




< 0.001

1.39 (1.24-1.55)

Unfractionated Heparin



< 0.001

1.49 (1.32-1.69)

Low Molecular Weight Heparin



> 0.001

2.59 (2.13-3.16)




< 0.001

0.56 (0.33-0.95)




< 0.001

1.43 (1.22-1.66)

Transfer patients, though, had longer delays to initiation of unfractionated heparin (35 vs 25 minutes), clopidogrel (119 vs 84 minutes), and GPIs (107 vs 60 min; P < 0.0001 for all). Administration of low molecular weight heparin and GPIs at the referral hospital was associated with longer delays to reperfusion compared with deferred administration at the STEMI-receiving hospital, while early use of unfractionated heparin was not. Transferred patients were also more likely to receive excess dosing, with the exception of GPIs (table 2).

Table 2. Excess Dosing of Anticoagulant and Antiplatelet Therapies According to Transfer Status


Transfer Patients

Nontransfer Patients

P Value

Adjusted OR (95% CI)

   Low Molecular



< 0.0001
< 0.001

1.28 (1.03-1.58)
1.25 (1.00-1.56)
1.15 (0.95-1.39)
1.54 (1.09-2.18)





0.85 (0.68-1.07)


After multivariable adjustment, GPI use at the referral hospital remained associated with delayed door-in/door-out times and reperfusion, while unfractionated heparin use was not. The use of low molecular weight heparin at the STEMI referral hospital resulted in a trend toward delayed reperfusion.

Major bleeding occurred in 11.0% of STEMI patients treated with primary PCI. After multivariable adjustment, transfer patients were modestly more likely to have a major bleeding complication (adjusted OR 1.10; 95% CI 1.03-1.17) compared with direct-arrival patients. This association remained unchanged after adjusting for excess dosing (adjusted OR 1.10; 95% CI 1.03-1.17).

“In summary, although transferred patients are more likely to receive antiplatelet and anticoagulant therapies prior to catheterization lab arrival, these therapies are often delayed and dosed in excess among transfer patients compared with direct-arrival STEMI patients treated with primary PCI,” the authors conclude. “This may, in part, contribute to the association of transfer status with greater bleeding risk. These results highlight an important target for quality improvement in the care of transferred STEMI patients.”

In an email with TCTMD, Sunil V. Rao, MD, also of the Duke Clinical Research Institute (Durham, NC), noted that the data are important since they involve a seldom studied and little understood cohort, namely patients transferred for primary PCI. Still, he expressed surprise at the results.

Right Thing at the Wrong Dose

“I would have expected the opposite,” Dr. Rao said, “namely, no treatment prior to transfer. It appears that referral hospitals are trying to do the right thing by starting therapy. Their challenge is to make sure that the therapy they start is dosed appropriately. This can be difficult since certain aspects of care, like renal function, may not be known prior to starting therapy. This is not an issue for unfractionated heparin but can be an issue for low molecular weight heparin and some IIb/IIIa inhibitors.”

Dr. Rao, who was not involved with the study, said he suspected the problems with medication prescribing are not limited to the hospitals surveyed.

He added that a team approach is necessary to correct the errors seen in the study, but the team concept must be expanded to include the referring hospital care providers. “The transfer systems are good with respect to getting patients to the PCI center quickly,” Dr. Rao said. “What we need to focus on now is making sure that the care at the referring hospital is also high quality. The way to do that is to have the referring hospital team and the receiving hospital team get on the same page and ensure that there is a protocol/pathway in place for patients who are being referred.”

According to David P. Faxon, MD, of Brigham and Women’s Hospital (Boston, MA), improvements in the system for transferring patients for primary PCI still come down to a matter of time. “The effort should be made to transfer more rapidly,” Dr. Faxon told TCTMD in an email. “The [American Heart Association] and others are working to improve the timely transfer of patients and the goal is 30 minutes for door-in door-out for transferred patients. This still needs considerable work with improvement in the processes at the referral hospitals.”


Wang TY, Magid DJ, Ting HH, et al. The quality of antiplatelet and antiocoagulant medication administration among ST-elevation myocardial infarction patients transferred for primary percutaneous coronary intervention. Am Heart J. 2014;Epub ahead of print.



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  • The paper provides no information regarding conflicts of interest.
  • Drs. Rao and Faxon report no relevant conflicts of interest.