Troponin-positive, MB-negative patients with non-ST-elevation myocardial infarction: An undertreated but high-risk patient group: Results from the National Cardiovascular Data Registry Acute Coronary Treatment and Intervention Outcomes Network-Get With The Guidelines (NCDR ACTION-GWTG) Registry
ABSTRACT Despite the 2000 and 2007 redefinition of myocardial infarction (MI), patients who are troponin (Tn) positive ([+]) but MB negative ([-]) may not be considered to have MI, particularly in the absence of known coronary disease (prior MI or revascularization; coronary artery disease [CAD]). How this affects treatment and outcomes has not been well described.
Direct arrival patients with non-ST elevation MI (NSTEMI) enrolled in the American College of Cardiology NCDR ACTION-GWTG Registry were included. Patients missing marker data who were Tn (-) and had CAD were excluded. Troponin (+) patients were categorized as MB (+) (n = 11,563) or MB (-) (n = 4,501). Treatments and in-hospital outcomes were compared between the 2 groups using logistic regression.
Of the 16,064 NSTEMI patients, 28% were MB (-). The MB (-) patients were older (median age 68 vs 65 years) and had more comorbidities (hypertension 71% vs 66%, diabetes 31% vs 27%, heart failure 22% vs 19%; all Ps < .01). After adjusting for baseline characteristics, MB (-) patients were significantly less likely to receive clopidogrel, antithrombins, glycoprotein IIb/IIIa antagonists, or angiography (all Ps < .001). In-hospital mortality was lower in MB (-) patients (3.8% vs 4.9%, P < .01), which remained significant after adjusting for baseline variables (odds ratio 0, 69, 95% CI 0.6-0.9, P = .002).
Patients without known CAD who have NSTEMI and are MB (-) have a higher risk profile but are less likely to receive guideline-recommended acute pharmacologic treatment than those who are MB (+). Given the relatively high mortality in this group, increased emphasis on improving quality of care in Tn (+)/MB (-) patients is warranted.
Article: ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: The Task Force for the management of acute coronary syndromes (ACS) in patients presenting without persistent ST-segment elevation of the European Society of Cardiology (ESC)European Heart Journal 08/2011; 32(23):2999-3054. DOI:10.1093/eurheartj/ehr236 · 14.72 Impact Factor
- Journal of the American College of Cardiology 11/2011; 58(22):2342-54. DOI:10.1016/j.jacc.2011.08.042 · 15.34 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: This review highlights an important novel aspect of the 2011 ESC guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: the recommendations of a rapid rule-out protocol (0h and 3h) when high-sensitive cardiac troponin assays are available. The controversy relates to the scientific question how reliably patients can recall the onset or maximum of acute chest pain and the general question how conservative clinical practice guidelines should be. Several important arguments support the novel recommendations, particularly when accepting that guidelines should highlight treatment principles rather than individualised details. I hope that many physicians caring for patients with acute chest pain will actually take the time to read the new 2011 ESC guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation. Certainly, application of the principles highlighted in there will help them in their daily clinical work.Schweizerische medizinische Wochenschrift 03/2012; 142:w13514. DOI:10.4414/smw.2012.13514 · 1.88 Impact Factor