Author + information
- Michael Ringborn,
- Yochai Birnbaum,
- Søren Steen Nielsen,
- Olle Pahlm,
- Galen S. Wagner,
- Christian Juhl Terkelsen and
- Pyotr G. Platonov
Symptom-to-balloon time predicts outcome in ST elevation myocardial infarction (STEMI) patients treated with primary PCI. Limited data suggest grade 3 ischemia (G3) on admission ECG to reflect severe ischemia prone to rapid infarct evolution, however the value of G3 on pre-hospital ECG is unknown. We aimed to assess if the effect of symptom-to-balloon time on salvage depends on ischemia grade on the pre-hospital ECG.
In 245 STEMI patients, pre-hospital 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). Salvage was calculated from myocardial area at risk (MaR) and infarct size (IS) at day 30 by single-photon emission computerized tomography as (MaR-IS)/MaRx100. Patients were stratified according to symptom-to-balloon time as early or late (<2.5 or ≥2.5 hours).
G3 criteria were met by 50 (early/late; 15/35), and G2 by 195 (43/152) pts. Symptom to ECG - and balloon times were similar among groups. G3 pts treated late had lower salvage and larger IS than G2 (Table). Beyond 2.5 hours, inverse relation between symptom-to-balloon time and salvage was observed for G2 (r=−0.22, p=0.008) but not G3 (r= −0.23; p=0.19), however in early-treated G3 the relation was r=−0.58, p=0.024.
G3 ischemia at pre-hospital stage in STEMI patients could be a sign of more severe ischemia with faster progression of necrosis over time.
|G2 ischemia (n=195)||G3 ischemia (n=50)||p-value|
|Symptom to ECG (min)||95[51–184]||111[41–157]||0.79|
|Symptom to balloon (min)||204[161–296]||199[143–283]||0.37|
|Salvage (%) total||63 [37–91]||55 [36–81]||0.21|
|<2.5 hours||75 [36–96]||72[49–96]||0.64|
|>2.5 hours||62 [40–87]||48[35–78]||0.042|
|IS (% of left ventricle) total||7[1–18]||11 [3–25]||0.047|
|<2.5 hours||4 [1–13]||3 [1–14]||0.90|
|> 2.5 hours||8 [2–20]||16 [5–29]||0.015|
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: 1212-174
- 2013 American College of Cardiology Foundation