Intracoronary ECG ST-segment recovery during primary percutaneous intervention for ST-segment myocardial infarction: insights from a cardiac MRI study.

ST-segment-resolution (STR) on surface electrocardiogram (ECG) is a good surrogate for myocardial reperfusion in patients with acute ST-segment-elevation-myocardial-infarction (STEMI). We sort to determine the optimal criteria of measuring STR on intracoronary-ECG (IC-ECG) for prediction of myocardial injury evaluated by cardiac MRI (CMR). Measurements of IC-ECG ST-segments were performed at baseline, immediately after (early) and 15 min (late) after achieving TIMI-3 flow during primary-PCI. The degree of ST-segment-shift from baseline noted upon the IC-ECG was divided into four groups: (group 1) ST-segment-resolution >1 mm, (group 2) <30% resolution, (group 3) >50% resolution, (group 4) >70% resolution at both early and late time points. Patients had CMR at days 3 and 90 postprimary-PCI. Fifty two patients (aged 60 ± 11 years; 43 males) were evaluated. Early intracoronary-ECG ST-segment resolution (early IC-STR >1 mm) correlated with smaller scar mass (P = 0.003), nonviable myocardial mass (P < 0.001), and microvascular obstruction (MVO) (P = 0.004) on CMR at day 3. Ejection fraction (EF) was also better at day 3 (P = 0.026) and 90 (P = 0.039). Patients with poor early IC-STR (IC-STR <30%) conversely is associated with larger scar mass (P = 0.017), nonviable myocardial mass (P = 0.01), and MVO (P = 0.021) at day 3. This was also associated with worse EF at day 90 (P = 0.044). Neither group 3 or 4, or the late measurements of late IC-STR correlated with CMR markers of myocardial injury. The degree of early IC-STR (defined by IC-STR > 1 mm or <30%) successfully predicts myocardial damage following primary-PCI for an acute STEMI. Further studies are required to investigate its potential utility.

Wong DT ，Leung MC ，Das R ，Puri R ，Liew GY ，Teo KS ，Chew DP ，Meredith IT ，Worthley MI ，Worthley SG ... -  《-》

Intracoronary ECG during primary percutaneous coronary intervention for ST-segment elevation myocardial infarction predicts microvascular obstruction and infarct size.

Microvascular obstruction (MVO) following ST-segment elevation myocardial infarction (STEMI) is associated with larger infarct size and an increased mortality. Although angiographic predictors of MVO in primary percutaneous coronary intervention (primary-PCI) setting have been identified, an earlier and objective "in-lab" predictor may be beneficial, in order to potentially influence therapies administered during primary-PCI. We hypothesised that intracoronary-electrocardiogram (IC-ECG) is a simple, objective and accurate predictor of MVO evaluated by cardiac magnetic resonance (CMR) and is comparable to myocardial blush grade (MBG) and TIMI myocardial perfusion grade (TMPG). Intracoronary ECG was performed during primary-PCI. Intracoronary ST-segment measurement was performed before and immediately after opening of infarct-related-artery. Intracoronary ST-segment resolution (IC-STR) was defined as ≥ 1 mm improvement compared to baseline. Contrast enhanced CMR was performed at 4 and 90 days post primary-PCI. Primary endpoint was MVO on late gadolinium hyperenhancement assessed by CMR at day 4. Sixty-four consecutive patients (age 59 ± 11 years; 55 males) were recruited. Intracoronary ST-segment resolution correlated with MVO (p=0.005). Furthermore, IC-STR correlated with infarct-mass, non-viable-mass, peak creatinine kinase and end-systolic-volume at day 4. Intracoronary ST-segment resolution also correlated with favourable left ventricular end-diastolic-volume at day 90 (p=0.022). On multivariate analysis, IC-STR was an independent predictor of MVO. Intracoronary ST-segment resolution is a strong in-lab predictor of MVO assessed 4 days after STEMI on CMR. Furthermore, IC-STR correlates with infarct size and left ventricular remodelling at 3 months. Further studies are required to understand potential clinical utility of this tool.

Wong DT ，Leung MC ，Das R ，Liew GY ，Teo KS ，Chew DP ，Meredith IT ，Worthley MI ，Worthley SG ... -  《-》

[Rapid resolution of ST segment elevation predicts recovery of left myocardial contraction in patients with acute myocardial infarction treated with percutaneous coronary angioplasty].

Tomaszuk-Kazberuk A ，Korecki J ，Kochman W ，Dobrzycki S ，Musiał WJ ... -  《-》

Early electrocardiographic findings and MR imaging-verified microvascular injury and myocardial infarct size.

Nijveldt R ，van der Vleuten PA ，Hirsch A ，Beek AM ，Tio RA ，Tijssen JG ，Piek JJ ，van Rossum AC ，Zijlstra F ... -  《-》

Intracoronary ST segment evolution during primary coronary stenting predicts infarct zone recovery.

Balian V ，Galli M ，Repetto S ，Luvini M ，Galdangelo F ，Castiglioni B ，Boscarini M ，Petrucci E ，Filippini G ，Marcassa C ... -  《CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS》