Relationship between admission Q waves and microvascular injury in patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention

Deciphering the Enigma of Intramyocardial Hemorrhage Following Reperfusion Therapy in Acute ST-Segment Elevation Myocardial Infarction: A Comprehensive Exploration from Mechanisms to Therapeutic Strategies

Acute ST-segment elevation myocardial infarction (STEMI) is a formidable challenge in cardiovascular medicine, demanding advanced reperfusion strategies such as emergency percutaneous coronary intervention. While successful revascularization is pivotal, the persistent "no-reflow" phenomenon remains a clinical hurdle, often intertwined with microvascular dysfunction. Within this intricate scenario, the emergence of intramyocardial hemorrhage (IMH) has garnered attention as a significant contributor. This review offers a detailed exploration of the multifaceted relationship between IMH and the "no-reflow" phenomenon, delving into the mechanisms governing IMH occurrence, state-of-the-art diagnostic modalities, predictive factors, clinical implications, and the evolving landscape of preventive and therapeutic strategies. The nuanced examination aims to deepen our comprehension of IMH, providing a foundation for the identification of innovative therapeutic avenues and enhanced clinical outcomes for STEMI patients.

Relation of plasma neuropeptide-Y with myocardial function and infarct severity in acute ST-elevation myocardial infarction

BACKGROUND

Acute myocardial infarction is associated with the release of the co-transmitter neuropeptide-Y (NPY). NPY acts as a potent vasoconstrictor and is associated with microvascular dysfunction after ST-elevation myocardial infarction (STEMI). This study comprehensively evaluated the association of plasma NPY with myocardial function and infarct severity, visualized by cardiac magnetic resonance (CMR) imaging, in STEMI patients revascularized by primary percutaneous coronary intervention (PCI).

METHODS

In this observational study, we included 260 STEMI patients enrolled in the prospective MARINA-STEMI (NCT04113356) study. Plasma NPY concentrations were measured by an immunoassay 24h after PCI from peripheral venous blood samples. Left ventricular ejection fraction (LVEF), global longitudinal strain (GLS), infarct size (IS) and microvascular obstruction (MVO) were determined using CMR imaging.

RESULTS

Median plasma concentrations of NPY were 70 [interquartile range (IQR):35-115] pg/ml. NPY levels above median were significantly associated with lower LVEF (48%vs.52%, p=0.004), decreased GLS (-8.8%vs.-12.6%, p<0.001) and larger IS (17%vs.13%, p=0.041) in the acute phase after infarction as well as after 4 months (LVEF:50%vs.52%, p=0.030, GLS:-10.5vs.-12.9,p<0.001,IS:13%vs.10%,p=0.011). In addition, NPY levels were significantly related to presence of MVO (58%vs.52%, p=0.041). Moreover, in multivariable linear regression analysis, NPY remained significantly associated with all investigated CMR parameters (LVEF:p<0.001,GLS:p<0.001,IS:p=0.003,MVO:p=0.042) independent of other established clinical variables including high-sensitivity cardiac troponin T, pre-interventional TIMI flow 0 and left anterior descending artery as culprit lesion location.

CONCLUSION

High plasma levels of NPY, measured 24h after STEMI, were independently associated with lower LVEF, decreased GLS, larger IS as well as presence of MVO, indicating plasma NPY as a novel clinical risk marker post STEMI.

The prognostic significance of Q waves and T wave inversions in the ECG of patients with STEMI: A substudy of the TOTAL trial

BACKGROUND

The prognostic significance of Q waves and T-wave inversions (TWI) combined and separately in STEMI patients undergoing primary PCI has not been well established in previous studies.

METHODS

We included 7,831 patients from the TOTAL trial and divided the patients into categories based on Q waves and TWIs in the presenting ECG. The primary outcome was a composite of cardiovascular death, recurrent myocardial infarction (MI), cardiogenic shock or new or worsening NYHA class IV heart failure within one year. The study evaluated the effect of Q waves and TWI on the risk of primary outcome and all-cause death, and whether patient benefit of aspiration thrombectomy differed between the ECG categories.

RESULTS

Patients with Q+TWI+ (Q wave and TWI) pattern had higher risk of primary outcome compared to patients with Q-TWI- pattern [33 (10.5%) vs. 221 (4.2%); adjusted hazard ratio (aHR) 2.10; 95% CI, 1.45-3.04; p<0.001] within 40-days' period. When analyzed separately, patients with Q waves had a higher risk for the primary outcome compared to patients with no Q waves in the first 40 days [aHR 1.80; 95% CI, 1.48-2.19; p<0.001] but there was no additive risk after 40 days. Patients with TWI had a higher risk for primary outcome only after 40 days when compared to patients with no TWI [aHR 1.63; 95% CI, 1.04-2.55; p=0.033]. There was a trend towards a benefit of thrombectomy in patients with the Q+TWI+ pattern.

CONCLUSIONS

Q waves and TWI combined (Q+TWI+ pattern) in the presenting ECG is associated with unfavourable outcome within 40-days. Q waves tend to affect short-term outcome, while TWI has more effect on long-term outcome.

Assessment of a New Electrocardiographic Marker for the Diagnosis of Myocardial Infarction With Non-obstructive Coronary Arteries

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is clinically defined as myocardial infarction in the absence of obstructive atherosclerosis on coronary angiography. Diagnosis may require multiple diagnostic tools in addition to standard coronary angiography, including cardiac imaging or provocative tests, according to clinical suspicion. We assessed the usefulness of the DETERMINE (Defibrillators to Reduce Risk by Magnetic Resonance Imaging Evaluation) score for distinguishing patients with MINOCA from those with non-ST segment elevation myocardial infarction with obstructive coronary artery disease (NSTEMI-CAD) in a single-center observational study. The patients were divided into two groups according to coronary angiography findings. The study included 277 patients: 227 with NSTEMI-CAD and 50 with MINOCA. The DETERMINE score (6.1 ± 3.7 vs 1.9 ± 2.1, P<.001) was significantly higher in the NSTEMI-CAD than MINOCA group. Logistic regression analysis revealed that the DETERMINE score (OR=0.591, P<0.001) was an independent predictor of MINOCA. The incidence of diabetes mellitus and glucose levels were significantly higher in the NSTEMI-CAD group; however, ejection fraction was significantly higher in the MINOCA group (P<0.05). Our findings suggest that the DETERMINE score constitutes a simple and inexpensive tool for the assessment of MINOCA.

Estimating the extent of myocardial damage in patients with STEMI using the DETERMINE score

Background

Recently, a simple ECG score (DETERMINE score) has been proposed for estimating myocardial scar in patients with ischaemic cardiomyopathy. We sought to evaluate the usefulness of the DETERMINE score for the assessment of myocardial infarct size (IS) as well as microvascular obstruction (MVO), in the setting of ST-elevation myocardial infarction (STEMI).

Methods

This observational study enrolled 423 patients with STEMI (median age 56, 17% women), revascularised by primary percutaneous coronary intervention (PCI). For evaluation of the DETERMINE and Selvester scoring system (an established but complex ECG score for IS estimation), ECG was conducted before discharge (median: 4 (IQR 2–6) days). Cardiac magnetic resonance (CMR) was conducted within a week after infarction for determination of IS and MVO.

Results

Median DETERMINE score of the overall cohort was 8 points (IQR 5–11). A higher DETERMINE score was significantly associated with a larger IS (21% vs 11% of left ventricular myocardial mass (LVMM), p<0.001) as well as larger MVO (1.2% vs 0.0% of LVMM, p<0.001). In linear and binary multivariable logistic regression analysis, the DETERMINE score remained independently associated with IS (OR 1.09, 95% CI 1.02 to 1.17, p=0.014) and MVO (OR 1.12, 95% CI 1.04 to 1.21, p=0.003), after adjustment for Selvester score and clinical indicators of IS (high-sensitivity cardiac troponin T, high-sensitivity C reactive protein, N-terminal pro-B-type natriuretic peptide, TIMI flow pre-interventional and post-interventional PCI, anterior infarct localisation).

Conclusions

In patients undergoing PCI for STEMI, the DETERMINE score provides an easy and inexpensive tool for appropriate estimation of infarct severity as determined by CMR.

The high-risk ECG pattern of ST-elevation myocardial infarction: A substudy of the randomized trial of primary PCI with or without routine manual thrombectomy (TOTAL trial)

BACKGROUND

Useful tools for risk assessment in patients with STEMI are needed. We evaluated the prognostic impact of the evolving myocardial infarction (EMI) and the preinfarction syndrome (PIS) ECG patterns and determined their correlation with angiographic findings and treatment strategy.

METHODS

This substudy of the randomized Trial of Routine Aspiration Thrombectomy with PCI versus PCI Alone in Patients with STEMI (TOTAL) included 7860 patients with STEMI and either the EMI or the PIS ECG pattern. The primary outcome was a composite of death from cardiovascular causes, recurrent MI, cardiogenic shock, or New York Heart Association (NYHA) class IV heart failure within one year.

RESULTS

The primary outcome occurred in 271 of 2618 patients (10.4%) in the EMI group vs. 322 of 5242 patients (6.1%) in the PIS group [AdjustedHR, 1.54; 95% CI, 1.30 to 1.82; p < .001]. The primary outcome occurred in the thrombectomy and PCI alone groups in 131 of 1306 (10.0%) and 140 of 1312 (10.7%) patients with EMI [HR 0.94; 95% CI, 0.74-1.19] and 162 of 2633 (6.2%) and 160 of 2609 (6.1%) patients with PIS [HR 1.00; 95% CI, 0.81-1.25], respectively (p_interaction = 0.679).

CONCLUSIONS

Patients with the EMI ECG pattern proved to have an increased rate of the primary outcome within one year compared to the PIS pattern. Routine manual thrombectomy did not reduce the risk of primary outcome within the different dynamic ECG patterns. The PIS/EMI dynamic ECG classification could help to triage patients in case of simultaneous STEMI patients with immediate need for pPCI.