High QRS score on admission strongly predicts impaired myocardial reperfusion in patients with a first anterior acute myocardial infarction

Culprit Lesion Morphology of Rapidly Progressive and Extensive Anterior-Wall ST-Segment Elevation Myocardial Infarction

BACKGROUND

Rapidly progressive, extensive myocardial injury/infarction (RPEMI) beyond the concept of wave-front phenomenon can be observed even when achieving timely reperfusion; however, the pathogenesis of RPEMI remains unknown. This retrospective study investigated clinical and lesion characteristics of RPEMI, focusing on culprit-lesion morphology (CLM).

METHODS

Among patients with extensive anterior-wall ST-segment elevation myocardial infarction due to proximal left anterior descending artery lesions who had reperfusion within 3 hours of symptom onset, 60 patients undergoing both intravascular ultrasound and cardiac magnetic resonance imaging were enrolled. Myocardial injury/infarction before reperfusion therapy was assessed by QRS scores at hospitalization electrocardiogram, and the extent of myocardial injury/infarction was evaluated by cardiac magnetic resonance imaging, which measured area at risk, infarct size, myocardial salvage index, microvascular obstruction, and left ventricular ejection fraction. RPEMI was defined as lower left ventricular ejection fraction (less median value) with microvascular obstruction.

RESULTS

Despite comparable onset-to-door and onset-to-reperfusion times and area at risk, patients with RPEMI showed higher QRS scores at hospitalization (5 [4.3-6] versus 3 [2-4], P<0.001) and infarct size (26.5±9.1 versus 20.4±10.5%, P=0.04), and a tendency toward lower myocardial salvage index (0.27±0.14 versus 0.36±0.20, P=0.10) compared with those without. Patients with versus without RPEMI more frequently observed specific CLM on intravascular ultrasound, characterized by the combination of vulnerable plaques, plaque ruptures, and/or large thrombi. When stratified by CLM-score composed of these 3 criteria, higher CLM-scores were or tended to be associated with higher QRS scores and incidence of RPEMI. In multivariate analyses including no-reflow phenomenon and final coronary-flow deterioration, increased CLM-score (≥2) was independently associated with high QRS scores and RPEMI (odd ratio 11.25 [95% CI, 2.43-52.00]; P=0.002).

CONCLUSIONS

Vulnerable CLM was a consistent determinant of advanced myocardial injury/infarction both before and after reperfusion therapy and may play a pivotal role in the development of RPEMI.

Prognostic Significance of a Combination of QRS Score and E/e' Obtained 2 Weeks After the Onset of ST-Elevation Myocardial Infarction

BACKGROUND

The early mitral inflow velocity to mitral early diastolic velocity ratio (E/e') and electrocardiogram (ECG) determination of QRS score are useful for risk stratification in patients with ST-elevation myocardial infarction (STEMI).Methods and Results:In this study, 420 consecutive patients (357 male; mean [±SD] age 63.6±12.2 years) with first-time STEMI who successfully underwent primary percutaneous coronary intervention within 12 h of symptom onset were followed-up for 5 years (median follow-up 67 months). Echocardiography, ECG, and blood samples were obtained 2 weeks after onset. Infarct size was estimated by the QRS score after 2 weeks (QRS-2wks) and creatine phosphokinase-MB concentrations (peak and area under the curve). The primary endpoint was death from cardiac causes or rehospitalization for heart failure (HF). During follow-up, 21 patients died of cardiac causes and 62 had HF. Multivariate Cox proportional hazard analysis showed that mean E/e' (hazard ratio [HR] 1.152; 95% confidence interval [CI] 1.088-1.215; P<0.0001), QRS-2wks (HR 1.153; 95% CI 1.057-1.254; P<0.0001), and hypertension (HR 1.702; 95% CI 1.040-2.888; P=0.03) were independent predictors of the primary endpoint. Kaplan-Meier curve analysis showed that patients with QRS-2wks >4 and mean E/e' >14 were at an extremely high risk of cardiac death or HF (log rank, χ²=116.3, P<0.0001).

CONCLUSIONS

In patients with STEMI, a combination of QRS-2wks and mean E/e' was a simple but useful predictor of cardiac death and HF.

Both baseline Selvester QRS score and change in QRS score predict prognosis in patients with acute ST-segment elevation myocardial infarction after percutaneous coronary intervention

We aimed to demonstrate the prognostic value of Selvester QRS scores in patients with acute ST-segment elevation myocardial infarction (STEMI).

Correlation of QRS duration with myocardial blush grade as a marker of myocardial reperfusion in primary percutaneous coronary intervention

Background

The association between duration of QRS and myocardial reperfusion is not very well established. Our aim was to assess the relationship between measurements of QRS duration and myocardial blush grade (MBG) in patients with ST-elevation myocardial infarction (STEMI) who were treated with a primary percutaneous coronary intervention (PCI).

Methods

Between January 2016 and June 2017, 200 patients with STEMI who presented within 12 h of symptom onset and taken up for primary PCI were analyzed with electrocardiogram (ECG) before and after the procedure. Two study groups were then defined on the basis of microvascular perfusion: group A (MBG 0-1) and group B (MBG 2-3).

Results

Group A had a total of 80 patients, and group B had 120 patients. The baseline characteristics were similar in the two groups. QRS duration was found to be longer in group A compared with group B at both the immediate ECG (95.5 ± 15.63 vs 80.87 ± 12.80 msec, p < 0.001, respectively) and at the 60th minute ECG (96.95 ± 16.2 vs 78.82 ± 12.08 msec, p < 0.001, respectively) post angioplasty. Significant difference was detected between the two groups post-angioplasty at both the immediate (10.99 ± 10.05 vs −6.64 ± 10.61 msec, p < 0.001) and the 60th minute (13.03 ± 11.64 vs −7.95 ± 11.11 msec, p < 0.001) ECG. Using receiver operator curve analysis, we found that QRS complex narrowing of 4.5 msec post angioplasty was the best cutoff value for predicting reperfusion.

Conclusion

QRS duration change post angioplasty is strongly correlated with the myocardial reperfusion in patients presenting with STEMI.

QRS Score at Presentation Electrocardiogram Is Correlated With Infarct Size and Mortality in ST-Segment Elevation Myocardial Infarction Patients Undergoing Primary Percutaneous Coronary Intervention

BACKGROUND

In ST-segment elevation myocardial infarction (STEMI), QRS score at presentation ECG may reflect the progression of infarction and facilitate prediction of the degree of myocardial salvage achieved by reperfusion therapy.Methods and Results:Admission electrocardiogram (ECG) was studied in 2,607 patients with STEMI undergoing primary percutaneous coronary intervention (PCI) within 24 h of symptom onset. Patients were classified into 3 groups according to QRS score: low (0-3, n=1,227), intermediate (4-7, n=810), and high (≥8, n=570). An increase of infarct size estimated by median peak creatine phosphokinase was observed as QRS score increased (low score, 1,836 IU/L; inter-quartile range (IQR), 979-3,190 IU/L; intermediate score, 2,488 IU/L; IQR, 1,126-4,640 IU/L; high score, 3,454 IU/L; IQR, 1,759-5,639 IU/L; P<0.001). Higher QRS score was associated with higher long-term mortality (low, intermediate, and high score, 15.6%, 19.7%, and 23.7% at 5 years, respectively; log-rank P<0.001). The positive relationship of QRS score with mortality was consistently seen when stratified by infarct location. The association of high QRS score with increased mortality was most remarkably seen in patients with early (≤2 h) presentation (low, intermediate, and high score: 16.7%, 16.6%, and 28.1% at 5 years, respectively; log-rank P<0.001).

CONCLUSIONS

Higher QRS score at presentation ECG was associated with larger infarct size, and higher long-term mortality in patients with STEMI undergoing primary PCI. QRS score appears to be important in the early risk stratification for STEMI.

The association between prolongation in QRS duration and presence of coronary collateral circulation in patients with acute myocardial infarction

BACKGROUND

It is known that QRS duration is related to prognosis in acute myocardial infarction. The relation between QRS duration and coronary collateral circulation is uncertain. In the present study, we aimed to determine the relation between QRS duration and coronary collateral circulation in patients admitted with acute myocardial infarction.

METHODS

The present study was composed of 109 consecutive patients with acute myocardial infarction. All patients had total occlusion in the left anterior descending coronary artery. Electrocardiographic recordings on admission were obtained for the assessment of QRS duration. The Rentrop classification was used to define coronary collateral circulation on coronary angiography. Patients were divided into two groups as follows: Group 1 with poor coronary collateral circulation (Rentrop 0-1) and Group 2 with good coronary collateral circulation (Rentrop 2-3).

RESULTS

Of all patients, 62 patients were included in group 1 and 47 patients in group 2, respectively. In the present study, patients in the group 1 had longer QRS duration than patients in the group 2 (p < 0.005). Additionally, we found that Rentrop grading had negative correlation with both QRS duration and white blood cell count (r: -0.28; p < 0.005 and r: -0.35; p < 0.001).

CONCLUSION

Our study showed that there was an inverse relationship between QRS duration on admission and presence of coronary collateral circulation in patients with acute myocardial infarction.

QRS duration: a novel marker of microvascular reperfusion as assessed by myocardial blush grade in ST elevation myocardial infarction patients undergoing a primary percutaneous intervention

Objectives

Prolonged QRS duration is a predictor of poor prognosis in patients with coronary artery disease. The association between the duration of QRS and myocardial reperfusion is not very well understood. Our aim was to assess the relationship between the measurements of QRS duration and myocardial blush grade (MBG) in patients with ST elevation myocardial infarction (STEMI) who were treated with a primary percutaneous intervention.

Patients and methods

A total of 213 patients (mean age: 57.5±11 years) with STEMI were included. ECG recordings were obtained for the evaluation of the QRS duration before and after primary percutaneous coronary intervention. Angiographic assessment in the infarct-related artery was performed using the MBG. Patients were categorized into two groups of those with impaired microvascular reperfusion (MBG: 0–1) and those with normal microvascular reperfusion (MBG: 2–3).

Results

Overall, 105 and 108 patients had an MBG of 0–1 or 2–3, respectively. There is no significant difference between patient’s characteristics. Despite the absence of a difference between two groups in terms of the QRS duration at presentation (P: 0.57), patients with impaired microvascular reperfusion were found to have longer QRS duration at immediately postprocedure (P: 0.003) and postprocedure 60 min time-points (P<0.001). Correlation analyses showed a positive correlation between pain-to-balloon time and QRS duration at postprocedure 60 min time-points (r: 0.137 and P: 0.04).

Conclusion

Our results suggest that longer QRS duration after angioplasty seemed to indicate the presence of impaired microvascular reperfusion in patients with STEMI.

Relationship between QRS score and microvascular obstruction after acute anterior myocardial infarction

BACKGROUND

The QRS score on electrocardiogram (ECG) in patients with myocardial infarction (MI) reportedly reflects the severity of myocardial damage. The presence of microvascular obstruction (MO) assessed by cardiac magnetic resonance (CMR) imaging is associated with irreversible myocardial damage. MO assessed by CMR is known to be a predictor for adverse clinical outcome after ST-elevation MI. The aim of the present study was to examine the relationship between QRS score and MO in acute anterior MI patients.

METHODS

Sixty-two patients with first acute anterior MI who successfully underwent primary percutaneous coronary intervention (PCI) were enrolled. The QRS score after PCI on admission ECG was calculated by a Selvester-Wagner QRS scoring system. CMR imaging was performed at 11.4±3.9 days after MI. MO was defined as delayed enhancement with contrast-devoid core. Patients were divided into two groups as follows: 37 patients who showed MO (MO group) and 25 patients who did not show it (non-MO group).

RESULTS

The QRS score was significantly greater in the MO group than in the non-MO group. The QRS score significantly correlated with MO volume (r=0.418, p=0.010). Multivariate analysis showed that the QRS score (odds ratio 1.362, 95% CI: 1.038-1.951, p=0.024) and the peak creatine kinase levels (odds ratio 1.001, 95% CI: 1.000-1.002, p<0.001) were independent predictors for MO.

CONCLUSIONS

Our results indicate that the QRS score derived from simple and widely available ECG may be a useful parameter for assuring the presence of MO.

Re-elevation of T-wave from day 2 to day 4 after successful percutaneous coronary intervention predicts chronic cardiac systolic dysfunction in patients with first anterior acute myocardial infarction

This study evaluates the clinical significance of re-elevation of T-wave in patients with ST segment elevation acute myocardial infarction (STEMI) undergoing successful percutaneous coronary intervention (PCI). Resolution of ST elevation within 24 h after reperfusion is associated with better outcome. However, little is known about the serial electrocardiography (ECG) changes and their significance. Seventy-five patients (52 men; 66 ± 1 years) with the first anterior STEMI in whom 12-lead ECG was recorded every day from day 0 to day 8 after PCI were studied. JT interval was quartered (points 1–5), and the deviations from isoelectric line at each point were analyzed in leads V2, V3, and V4. Serial ECG showed ST resolution and T-wave inversion within 2 days after PCI in all patients at the middle of JT interval (point 3), and subsequent re-elevation of T-wave on day 4 in 73 patients (97.3 %). The patients were divided into two groups: Group A (n = 37) with less JT deviation changes (<0.25 mV) from day 2 to day 4 at point 3; and Group B (n = 38) with greater JT deviation changes (≥0.25 mV). Group B had less retrograde collateral flow and longer JT interval in the acute phase, and lower left ventricular ejection fraction (LVEF), worse regional contractility, and higher plasma brain natriuretic peptide levels at 6 months after the onset than Group A (all P < 0.05). The JT deviation change was negatively correlated with and an independent predictor for LVEF in the chronic phase. Re-elevation ≥0.25 mV of T-wave at the middle of JT interval after successful PCI predicts chronic cardiac systolic dysfunction in patients with first anterior STEMI.