Author + information
- Michael Ringborn,
- Yochai Birnbaum,
- Søren Steen Nielsen,
- Olle Pahlm,
- Galen S. Wagner,
- Pyotr G. Platonov and
- Christian Juhl Terkelsen
In ST elevation myocardial infarction (STEMI), QRS distortion; grade 3 ischemia (G3) on admission ECG, is associated with larger infarct size (IS) and higher mortality. Scarce data exist on pre-hospital G3 evaluation, and none regarding temporal dynamics of ischemia grades before percutaneous coronary intervention. We aimed to test if these earlier findings are associated with max Troponin T (TnT), myocardial area at risk (MaR) and IS.
In 453 STEMI patients, pre-hospital and admission ECGs were classified as G3 (loss of S waves in V1-V3, or ST-elevation ≥0,5 of the R amplitude in ≥2 adjacent leads) or G2 (no QRS distortion) and pre-hospital dynamics (ST-resolution, Stable in G2, G3 changing to G2, G2 changing to G3 and Stable in G3) were determined. Max TnT (n=453) was registered, as well as MaR (n=285) and 30 day IS (n=401) by single-photon emission computerized tomography.
G3 criteria were met by 108, and G2 by 345 patients. Median time between pre- and inhospital ECG was 91(IQR, 49–193) min. The subgroups differed in TnT, MaR and IS (Table); p=0.0001. With group A as reference group B, D, E were associated with an increased MaR (B= 4.1; p= 0.03, B= 8.2; p=0.005, B=9.9; p=0.001) and IS (B= 3.5; p= 0.009, B= 4.4; p=0.03, B=9.5; p=0.0001).
QRS distortion is a dynamic ECG characteristic during STEMI that might allow risk stratification not only at admission, but also at pre-hospital stage.
|Group A; n=101 G3 or G2 to ST-resolution||Group B; n=179 Stable G2||Group C; n=31 G3 to G2||Group D; n=49 G2 to G3||Group E; n=57 Stable G3||p|
|Max Troponin T (μg/L)||1.5 [0.5–4.7]||4.9 [2.3–9.0]||6.1 [2.8–8.6]||8.2[5.1–10.6]||9.6 [5.9–12.5]||0.0001|
|MaR (% of left ventricle)||14.0 [4.0–30.0]||28.0 [18.0–42.0]||27.0 [15.5–31.5]||35.5 [28.3–45.0]||40.5 [32.2–46.2]||0.0001|
|IS (% of left ventricle)||2.0 [0–6.0]||10.0 [2.0–20.5]||7.5 [2.2–17.5]||11.0 [5.0–21.5]||19.5 [7.0–30.5]||0.0001|
Poster Sessions, Expo North
Sunday, March 10, 2013, 9:45 a.m.-10:30 a.m.
Session Title: Pre-Hospital ECG and Transfer: Time Is Myocardium
Abstract Category: 1. Acute Coronary Syndromes: Clinical
Presentation Number: 1212-177
- 2013 American College of Cardiology Foundation