Value of a new multiparametric score for prediction of microvascular obstruction lesions in ST-segment elevation myocardial infarction revascularized by percutaneous coronary intervention

Predicting the no-reflow phenomenon in ST-elevation myocardial infarction patients undergoing primary percutaneous coronary intervention: a systematic review of clinical prediction models

BACKGROUND

The no-reflow (NRF) phenomenon is the "Achilles heel" of interventionists after performing percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). No definitive treatment has been proposed for NRF, and preventive strategies are central to improving care for patients who develop NRF.

OBJECTIVES

In this study, we aim to investigate the clinical prediction models developed to predict NRF in STEMI patients undergoing primary PCI.

DESIGN

Systematic review.

DATA SOURCES AND METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were observed. Studies that developed clinical prediction modeling for NRF after primary PCI in STEMI patients were included. Data extraction was performed using the Checklist for Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modeling Studies (CHARMS) checklist. The Prediction Model Risk of Bias Assessment Tool (PROBAST) tool was used for critical appraisal of the included studies.

RESULTS

The three most common predictors were age, total ischemic time, and preoperative thrombolysis in myocardial infarction flow grade. Most of the included studies internally validated their developed model via various methods: random split, bootstrapping, and cross-validation. Only three studies (18%) externally validated their model. Six studies (37%) reported a calibration plot with or without the Hosmer-Lemeshow test. The reported area under the curve ranged from 0.648 to 0.925. The most common biases were in the statistical domain.

CONCLUSION

Clinical prediction models aid in individualizing care for STEMI patients with NRF after primary PCI. Of the 16 included studies, we report four to have a low risk of bias and low concern with regard to our research question, which should undergo external validation with or without updating in future studies.

Predilation Ballooning in High Thrombus Laden STEMIs: An Independent Predictor of Slow Flow/No-Reflow in Patients Undergoing Emergent Percutaneous Coronary Revascularization

Background

Distal embolization due to microthrombus fragments formed during predilation ballooning is considered one of the possible mechanisms of slow flow/no-reflow (SF/NR). Therefore, this study aimed to compare the incidence of intraprocedure SF/NR during the primary percutaneous coronary intervention (PCI) in patients with high thrombus burden (≥4 grade) with and without predilation ballooning for culprit lesion preparation. Methodology. This prospective descriptive cross-sectional study included patients with a high thrombus burden (≥4 grades) who underwent primary PCI. Propensity-matched cohorts of patients with and without predilation ballooning in a 1 : 1 ratio were compared for the incidence of intraprocedure SF/NR.

Results

A total of 765 patients with high thrombus burden undergoing primary PCI were included in this study. The mean age was 55.75 ± 11.54 years, and 78.6% (601) were males. Predilation ballooning was conducted in 346 (45.2%) patients. The incidence of intraprocedure SF/NR was significantly higher (41.3% vs. 27.4%; p < 0.001) in patients with predilation ballooning than in those without preballooning, respectively. The incidence of intraprocedure SF/NR also remained significantly higher for the predilation ballooning cohort with an incidence rate of 41.3% as against 30.1% (p=0.002) for the propensity-matched cohort of patients without predilation ballooning with a relative risk of 1.64 (95% CI: 1.20 to 2.24). Moreover, the in-hospital mortality rate remained higher but insignificant, among patients with and without predilation ballooning (8.1% vs. 4.9%; p=0.090).

Conclusion

In conclusion, predilation ballooning can be associated with an increased risk of incidence of intraprocedure SF/NR during primary PCI in patients with high thrombus burden.

Prediction of no-reflow phenomenon in patients treated with primary percutaneous coronary intervention for ST-segment elevation myocardial infarction

No-reflow is an important complication among patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI).A retrospective study of 1658 STEMI patients undergoing direct PCI was performed. Patients were randomly assigned at a 7:3 ratio into development cohort and validation cohort and into no-reflow and normal blood flow groups. Clinical data and laboratory examinations were compared to identify independent risk factors and establish a no-reflow risk scoring system.In the development cohort (n = 1122), 331 (29.5%) had no-reflow. Multivariate analysis showed age ≥ 65 years (OR = 1.766, 95% confidence interval (CI): 1.313-2.376, P < .001), not using angiotonase inhibitor/angiotensin receptor antagonists (OR = 1.454, 95%CI: 1.084-1.951, P = .013), collateral circulation <grade 2 (OR = 3.056, 95%CI: 1.566-5.961, P = .001), thrombosis burden ≥4 points (OR = 2.033, 95%CI: 1.370-3.018, P < .001), diameter of target lesion ≥3.5 mm (OR = 1.511, 95%CI: 1.087-2.100, P = .014), thrombosis aspiration (OR = 1.422, 95%CI: 1.042-1.941, P = .026), and blood glucose >8 mmol/L (OR = 1.386, 95%CI: 1.007-1.908, P = .045) were related to no-reflow. Receiver operating characteristic (ROC) area under the curve was 0.648 (95%CI: 0.609-0.86). At 0.349 cutoff sensitivity was 42.0%, specificity was 79.3%, positive predictive value (PPV) was 44.7%, negative predictive value (NPV) was 77.4%, P < .001. The resulting risk scoring system was tested in the validation cohort (n = 536), with 30.1% incidence of no-reflow. The area under the ROC curve was 0.637 (95%CI: 0.582-0.692). At a cutoff of 0.349 sensitivity was 53.2% and specificity was 66.7%, PPV was 41.2%, NPV was 76.4%, P < .001.The no-reflow risk scoring system was effective in identifying high-risk patients.

Cardiovascular magnetic resonance imaging assessment of outcomes in acute myocardial infarction

Cardiovascular magnetic resonance (CMR) imaging uniquely characterizes myocardial and microvascular injury in acute myocardial infarction (AMI), providing powerful surrogate markers of outcomes. The last 10 years have seen an exponential increase in AMI studies utilizing CMR based endpoints. This article provides a contemporary, comprehensive review of the powerful role of CMR imaging in the assessment of outcomes in AMI. The theory, assessment techniques, chronology, importance in predicting left ventricular function and remodelling, and prognostic value of each CMR surrogate marker is described in detail. Major studies illustrating the importance of the markers are summarized, providing an up to date review of the literature base in CMR imaging in AMI.

Prognostic significance of infarct core pathology revealed by quantitative non-contrast in comparison with contrast cardiac magnetic resonance imaging in reperfused ST-elevation myocardial infarction survivors

AIMS

To assess the prognostic significance of infarct core tissue characteristics using cardiac magnetic resonance (CMR) imaging in survivors of acute ST-elevation myocardial infarction (STEMI).

METHODS AND RESULTS

We performed an observational prospective single centre cohort study in 300 reperfused STEMI patients (mean ± SD age 59 ± 12 years, 74% male) who underwent CMR 2 days and 6 months post-myocardial infarction (n = 267). Native T1 was measured in myocardial regions of interest (n = 288). Adverse remodelling was defined as an increase in left ventricular (LV) end-diastolic volume ≥20% at 6 months. All-cause death or first heart failure hospitalization was a pre-specified outcome that was assessed during follow-up (median duration 845 days). One hundred and sixty (56%) patients had a hypo-intense infarct core disclosed by native T1. In multivariable regression, infarct core native T1 was inversely associated with adverse remodelling [odds ratio (95% confidence interval (CI)] per 10 ms reduction in native T1: 0.91 (0.82, 0.00); P = 0.061). Thirty (10.4%) of 288 patients died or experienced a heart failure event and 13 of these events occurred post-discharge. Native T1 values (ms) within the hypo-intense infarct core (n = 160 STEMI patients) were inversely associated with the risk of all-cause death or first hospitalization for heart failure post-discharge (for a 10 ms increase in native T1: hazard ratio 0.730, 95% CI 0.617, 0.863; P < 0.001) including after adjustment for left ventricular ejection fraction, infarct core T2 and myocardial haemorrhage. The prognostic results for microvascular obstruction were similar.

CONCLUSION

Infarct core native T1 represents a novel non-contrast CMR biomarker with potential for infarct characterization and prognostication in STEMI survivors. Confirmatory studies are warranted. CLINICALTRIALS.

GOV IDENTIFIER

NCT02072850.

Effect of microvascular obstruction and intramyocardial hemorrhage by CMR on LV remodeling and outcomes after myocardial infarction: a systematic review and meta-analysis

The goal of this systematic analysis is to provide a comprehensive review of the current cardiac magnetic resonance data on microvascular obstruction (MVO) and intramyocardial hemorrhage (IMH). Data related to the association of MVO and IMH in patients with acute myocardial infarction (MI) with left ventricular (LV) function, volumes, adverse LV remodeling, and major adverse cardiac events (MACE) were critically analyzed. MVO is associated with a lower ejection fraction, increased ventricular volumes and infarct size, and a greater risk of MACE. Late MVO is shown to be a stronger prognostic marker for MACE and cardiac death, recurrent MI, congestive heart failure/heart failure hospitalization, and follow-up LV end-systolic volumes than early MVO. IMH is associated with LV remodeling and MACE on pooled analysis, but because of limited data and heterogeneity in study methodology, the effects of IMH on remodeling require further investigation.

Prevalence and extent of infarct and microvascular obstruction following different reperfusion therapies in ST-elevation myocardial infarction

BACKGROUND

Microvascular obstruction (MVO) describes suboptimal tissue perfusion despite restoration of infarct-related artery flow. There are scarce data on Infarct Size (IS) and MVO in relation to the mode and timing of reperfusion. We sought to characterise the prevalence and extent of microvascular injury and IS using Cardiovascular magnetic resonance (CMR), in relation to the mode of reperfusion following acute ST-Elevation Myocardial Infarction (STEMI).

METHODS

CMR infarct characteristics were measured in 94 STEMI patients (age 61.0 ± 13.1 years) at 1.5 T. Seventy-three received reperfusion therapy: primary percutaneous coronary-intervention (PPCI, n = 47); thrombolysis (n = 12); rescue PCI (R-PCI, n = 8), late PCI (n = 6). Twenty-one patients presented late (>12 hours) and did not receive reperfusion therapy.

RESULTS

IS was smaller in PPCI (19.8 ± 13.2% of LV mass) and thrombolysis (15.2 ± 10.1%) groups compared to patients in the late PCI (40.0 ± 15.6%) and R-PCI (34.2 ± 18.9%) groups, p <0.001. The prevalence of MVO was similar across all groups and was seen at least as frequently in the non-reperfused group (15/21, [76%] v 33/59, [56%], p = 0.21) and to a similar magnitude (1.3 (0.0-2.8) v 0.4 [0.0-2.9]% LV mass, p = 0.36) compared to patients receiving early reperfusion therapy. In the 73 reperfused patients, time to reperfusion, ischaemia area at risk and TIMI grade post-PCI were the strongest independent predictors of IS and MVO.

CONCLUSIONS

In patients with acute STEMI, CMR-measured MVO is not exclusive to reperfusion therapy and is primarily related to ischaemic time. This finding has important implications for clinical trials that use CMR to assess the efficacy of therapies to reduce reperfusion injury in STEMI.

Cardioprotective Effects of Atorvastatin plus Trimetazidine in Percutaneous Coronary Intervention

Objective: To explore the effects of preoperative administration of conventional doses of atorvastatin plus trimetazidine on the myocardial injury of patients during the perioperative period of percutaneous coronary intervention (PCI).

Methodology: 475 cases of acute coronary syndrome patients before PCI were randomly divided into the control group (238 cases) and experimental group (237 cases).The control group was treated with conventional doses of atorvastatin calcium (20 mg each time, once a night), and the experimental group was treated with conventional doses of atorvastatin calcium plus trimetazidine hydrochloride (20 mg each time, tid) for 3 d. After PCI, preoperative and postoperative 24 h concentrations of serum creatine kinase MB isoenzyme (CK-MB), cardiac troponin I (cTnI) and high sensitivity C-reactive protein (hs-CRP) as well as activity of myeloperoxidase (MPO) were investigated. Left ventricular ejection fractions of the patients were then examined 4 weeks later.

Results: Postoperative 24 h cTnI concentration and elevated MPO activity of the experimental group were significantly lower than those of the control group (P <0 05). CK-MB activities and hs-CRP concentrations of the two groups did not differ significantly (P> 0 05).

Conclusion: The administration of conventional doses of atorvastatin plus trimetazidine three days before PCI is able to protect the perioperative patients from myocardial injury.

Cardiac MRI in the diagnosis of complications of myocardial infarction

The improvement in revascularization techniques and medicine treatment during infarction has substantially reduced mortality during the acute phase of this condition. Since the advent of kinetic sequences and the concomitant development of gadolinium chelates and delayed enhancement sequences, cardiac MRI has become the second-line reference examination for ischemic heart disease. The technique of delayed enhancement with the inversion recovery sequence performed after injection has been validated for numerous indications in ischemic disease. Delayed enhancement sequences make it possible in particular to look for "no-reflow" areas (microvascular obstructions), to quantify the infarction area, and to assess prognosis. MRI also allows us to define the area at risk, that is, the area with edema, and to look for and assess the mechanical complications of the infarction. The aim of this review is to summarize current knowledge about: the pharmacokinetic principles that regulate myocardial enhancement; the different sequences available to acquire delayed enhancement images, and; the value of cardiac MRI in the diagnosis of complications of myocardial infarction.

Incidence, predictors, and prognostic value of intramyocardial hemorrhage lesions in ST elevation myocardial infarction

BACKGROUND

Intra myocardial hemorrhage lesions (IMH) are underdiagnosed complication of ST elevation myocardial infarction (STEMI). We sought to determine the incidence, predictors and the prognostic value of IMH in STEMI using cardiac MR imaging (CMR) techniques.

METHODS

We screened for inclusion consecutive patients with STEMI treated by percutaneous coronary intervention (PCI) within the first 12 hr of evolution. IMH lesions were identified on T2-weighted sequences on CMR between days 4 and 8 after PCI. Adverse cardiac events were defined as a composite of death + severe ventricular arrhythmias + acute coronary syndrome + acute heart failure.

RESULTS

N = 114 patients were included and n = 11 patients (10%) presented IMH lesions. Patients with IMH lesions had a larger myocardial infarction extent (25.6 ± 1.8 vs. 13.5 ± 1.0 % LV mass, P < 0.01), microvascular obstructive lesions extent (4.6 ± 1.0 vs. 1.3 ± 0.3% LV mass, P < 0.01) and lower LV ejection fraction (40.7 ± 2.3% vs. 50.7 ± 1.3%, P < 0.01). The value of glycemia at admission was an independent predictor of IMH development (Odd ratio 1.8 [1.1-2.8] per mmol l(-1), P = 0.01). The incidence of adverse cardiac events was higher in the IMH group than in the non-IMH group during the first year following STEMI (P = 0.01, log-rank analysis). Cox regression analysis identified the presence of IMH lesions as an independent predictor of adverse clinical outcome (Hazard Ratio = 2.8 [1.2-6.8], P = 0.02).

CONCLUSION

Our study indicates that IMH is a rare but severe finding in STEMI, associated with a larger myocardial infarction and a worse clinical outcome. Per-PCI glycemia might influence IMH development.