Elsevier

American Heart Journal

Volume 168, Issue 6, December 2014, Pages 884-890
American Heart Journal

Clinical Investigation
Acute Ischemic Heart Disease
Incidence, angiographic features and outcomes of patients presenting with subtle ST-elevation myocardial infarction

https://doi.org/10.1016/j.ahj.2014.08.009Get rights and content

Background

Borderline electrocardiograms represent a challenge in ST-segment elevation myocardial infarction (STEMI) management and are associated with inappropriate discharges and delays to intervention.

Objectives

To assess angiographic characteristics and outcomes of patients presenting with subtle ST-elevation (STE) myocardial infarction.

Methods

A total of 504 consecutive patients with suspected STEMI treated by systematic primary percutaneous coronary intervention were prospectively included. Subtle STE was defined as a maximal preinterventional STE of 0.1 to 1 mm. Angiograms were interpreted by investigators unaware of the electrocardiographic data.

Results

The proportion of patients with subtle STE was 18.3%, 86% of them presented with Thrombolysis In Myocardial Infarction flow grade 0/1 and 91% underwent percutaneous coronary intervention. Despite having smaller infarcts, subtle STE patients associated more frequent multivessel disease (57% vs 44%, P = .02) and larger delays to reperfusion. During a follow-up of 19.0 ± 4.9 months, the rates of death or reinfarction were similar among groups (10.0% vs 12.6%, P = .467). Subtle STE was not associated with better outcomes neither in univariate nor after adjustment in a multivariate analysis (adjusted hazard ratio 0.79, 95% CI 0.37-1.69, P = .546).

Conclusions

Subtle STEMI is frequent in clinical practice and is usually associated with acute total coronary occlusion. Therefore, it should be diagnosed and treated in the same expeditiously manner as marked STEMI.

Section snippets

Study patients

We conducted a prospective registry of all STE myocardial infarction (STEMI) patients presenting to a tertiary care center with a 24/7 pPCI program between June 2008 and October 2011. During the study period, 504 patients with persistent ischemic symptoms not responding to nitrates plus any STE were admitted for emergent coronary angiography. Patients with cardiogenic shock and out-of-hospital cardiac arrest were also included.

Twenty-four patients were excluded from analysis because the final

Electrocardiographic analysis and clinical presentation

Subtle STE was present in 88 (18.7%) patients with suspected STEMI and in 82 (18.3%) patients with confirmed STEMI (Figure 2).

Two-thirds of subtle STE infarctions involved the inferior wall (Table I). There were 10 “true posterior” (inferobasal) and 4 hyperacute anterior infarctions in this group. No patient presented with isolated STE in aVR. Reciprocal changes were common among subtle STE patients; 28 (37%) had ST-segment depression of 0.5 to 0.9 mm, and 23 (31%) of ≥1.0 mm.

Multivessel

Discussion

In this contemporary, real-world study of consecutive STEMI patients undergoing reperfusion, we find that (1) subtle STE myocardial infarction (STEMI) is frequent, comprising 18% of current STEMI; (2) most of these patients present with an acute coronary occlusion (TFG 0/1) and merit subsequent PCI; and (3) many of them have extensive coronary disease and similar clinical outcomes compared with those with more obvious ST changes.

Because of its inherent risks, initial thrombolytic trials

Conclusions

Almost 1 in 5 STEMI patients presents with subtle STE, which is usually associated with acute total coronary occlusion. These patients have extensive disease and experience larger delays to reperfusion. Improvements in early recognition are of paramount importance to provide adequate treatment.

Disclosures

Relative to this investigation, there are no relationships with industry or any potential conflict of interests to disclose.

Acknowledgements

We are very grateful to Nieves Plana and the Clinical Biostatistics Unit of Ramón y Cajal Hospital.

References (26)

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a

Present address: Interventional Cardiology Unit, Department of Cardiology, Defense Central Hospital Gómez Ulla, University of Alcalá, Madrid, Spain.

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