Clinical Outcomes Associated With Various Microvascular Injury Patterns Identified by CMR After STEMI.

BACKGROUND: The prognostic significance of various microvascular injury (MVI) patterns after ST-segment elevation myocardial infarction (STEMI) is not well known. OBJECTIVES: This study sought to investigate the prognostic implications of different MVI patterns in STEMI patients. METHODS: The authors analyzed 1,109 STEMI patients included in 3 prospective studies. Cardiac magnetic resonance (CMR) was performed 3 days (Q1-Q3: 2-5 days) after percutaneous coronary intervention (PCI) and included late gadolinium enhancement imaging for microvascular obstruction (MVO) and T2∗ mapping for intramyocardial hemorrhage (IMH). Patients were categorized into those without MVI (MVO-/IMH-), those with MVO but no IMH (MVO+/IMH-), and those with IMH (IMH+). RESULTS: MVI occurred in 633 (57%) patients, of whom 274 (25%) had an MVO+/IMH- pattern and 359 (32%) had an IMH+ pattern. Infarct size was larger and ejection fraction lower in IMH+ than in MVO+/IMH- and MVO-/IMH- (infarct size: 27% vs 19% vs 18% [P < 0.001]; ejection fraction: 45% vs 50% vs 54% [P < 0.001]). During a median follow-up of 12 months (Q1-Q3: 12-35 months), a clinical outcome event occurred more frequently in IMH+ than in MVO+/IMH- and MVO-/IMH- subgroups (19.5% vs 3.6% vs 4.4%; P < 0.001). IMH+ was the sole independent MVI parameter predicting major adverse cardiovascular events (HR: 3.88; 95% CI: 1.93-7.80; P < 0.001). CONCLUSIONS: MVI is associated with future adverse outcomes only in patients with a hemorrhagic phenotype (IMH+). Patients with only MVO (MVO+/IMH-) had a prognosis similar to patients without MVI (MVO-/IMH-). This highlights the independent prognostic importance of IMH in assessing and managing risk after STEMI.

Mitral annular disjunction in out-of-hospital cardiac arrest patients-a retrospective cardiac MRI study.

BACKGROUND: Mitral annular disjunction (MAD), defined as defective attachment of the mitral annulus to the ventricular myocardium, has recently been linked to malignant arrhythmias. However, its role and prognostic significance in patients requiring cardiopulmonary resuscitation (CPR) remain unknown. This retrospective analysis aimed to describe the prevalence and significance of MAD by cardiac magnetic resonance (CMR) imaging in out-of-hospital cardiac arrest (OHCA) patients. METHODS: Eighty-six patients with OHCA and a CMR scan 5 days after CPR (interquartile range (IQR): 49 days before - 9 days after) were included. MAD was defined as disjunction-extent ≥ 1 mm in CMR long-axis cine-images. Medical records were screened for laboratory parameters, comorbidities, and a history of arrhythmia. RESULTS: In 34 patients (40%), no underlying cause for OHCA was found during hospitalization despite profound diagnostics. Unknown-cause OHCA patients showed a higher prevalence of MAD compared to definite-cause patients (56% vs. 10%, p < 0.001) and had a MAD-extent of 6.3 mm (IQR: 4.4-10.3); moreover, these patients were significantly younger (43 years vs. 61 years, p < 0.001), more often female (74% vs. 21%, p < 0.001) and had fewer comorbidities (hypertension, hypercholesterolemia, coronary artery disease, all p < 0.005). By logistic regression analysis, the presence of MAD remained significantly associated with OHCA of unknown cause (odds ratio: 8.49, 95% confidence interval: 2.37-30.41, p = 0.001) after adjustment for age, presence of hypertension, and hypercholesterolemia. CONCLUSIONS: MAD is rather common in OHCA patients without definitive aetiology undergoing CMR. The presence of MAD was independently associated to OHCA without an identifiable trigger. Further research is needed to understand the exact role of MAD in OHCA 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.

Culprit Lesion Vessel Size and Risk of Reperfusion Injury in ST-Segment Elevation Myocardial Infarction: A Cardiac Magnetic Resonance Imaging Study.

BACKGROUND: Microvascular obstruction (MVO) and intramyocardial hemorrhage (IMH) are well-established imaging biomarkers of failed myocardial tissue reperfusion in patients with ST-segment elevation-myocardial infarction treated with percutaneous coronary intervention. MVO and IMH are associated with an increased risk of adverse outcome independent of infarct size, but whether the size of the culprit lesion vessel plays a role in the occurrence and severity of reperfusion injury is currently unknown. This study aimed to evaluate the association between culprit lesion vessel size and the occurrence and severity of reperfusion injury as determined by cardiac magnetic resonance imaging. METHODS AND RESULTS: Patients (n=516) with first-time ST-segment-elevation myocardial infarction underwent evaluation with cardiac magnetic resonance at 4 (3-5) days after infarction. MVO was assessed with late gadolinium enhancement imaging and IMH with T2* mapping. Vessel dimensions were determined using catheter-based reference. Median culprit lesion vessel size was 3.1 (2.7-3.6) mm. MVO and IMH were found in 299 (58%) and 182 (35%) patients. Culprit lesion vessel size was associated with body surface area, diabetes, total ischemic time, postinterventional thrombolysis in myocardial infarction flow, and infarct size. There was no association between vessel size and MVO or IMH in univariable and multivariable analysis (P>0.05). These findings were consistent across patient subgroups with left anterior descending artery and non-left anterior descending artery infarctions and those with thrombolysis in myocardial infarction 3 flow post-percutaneous coronary intervention. CONCLUSIONS: Comprehensive characterization of myocardial tissue reperfusion injury by cardiac magnetic resonance revealed no association between culprit lesion vessel size and the occurrence of MVO and IMH in patients treated with primary percutaneous coronary intervention for ST-segment-elevation myocardial infarction.

Association of dysglycaemia with persistent infarct core iron in patients with acute ST-segment elevation myocardial infarction.

BACKGROUND: Dysglycaemia increases the risk of myocardial infarction and subsequent recurrent cardiovascular events. However, the role of dysglycaemia in ischemia/reperfusion injury with development of irreversible myocardial tissue alterations remains poorly understood. In this study we aimed to investigate the association of ongoing dysglycaemia with persistence of infarct core iron and their longitudinal changes over time in patients undergoing primary percutaneous coronary intervention (PCI) for acute ST-segment elevation myocardial infarction (STEMI). METHODS: We analyzed 348 STEMI patients treated with primary PCI between 2016 and 2021 that were included in the prospective MARINA-STEMI study (NCT04113356). Peripheral venous blood samples for glucose and glycated hemoglobin (HbA1c) measurements were drawn on admission and 4 months after STEMI. Cardiac magnetic resonance (CMR) imaging including T2 * mapping for infarct core iron assessment was performed at both time points. Associations of dysglycaemia with persistent infarct core iron and iron resolution at 4 months were calculated using multivariable regression analysis. RESULTS: Intramyocardial hemorrhage was observed in 147 (42%) patients at baseline. Of these, 89 (61%) had persistent infarct core iron 4 months after infarction with increasing rates across HbA1c levels (<5.7%: 33%, ≥5.7: 79%). Persistent infarct core iron was independently associated with ongoing dysglycaemia defined by HbA1c at 4 months (OR: 7.87 [95% CI: 2.60-23.78]; p < 0.001), after adjustment for patient characteristics and CMR parameters. The independent association was present even after exclusion of patients with diabetes (pre- and newly diagnosed, n = 16). CONCLUSIONS: In STEMI patients treated with primary PCI, ongoing dysglycaemia defined by HbA1c is independently associated with persistent infarct core iron and a lower likelihood of iron resolution. These findings suggest a potential association between ongoing dysglycaemia and persistent infarct core iron, which warrants further investigation for therapeutic implications.

Infarct severity and outcomes in ST-elevation myocardial infarction patients without standard modifiable risk factors - A multicenter cardiac magnetic resonance study.

BACKGROUND: Standard modifiable cardiovascular risk factors (SMuRFs) are well-established players in the pathogenesis of ST-elevation myocardial infarction (STEMI). However, in a significant proportion of STEMI patients, no SMuRFs can be identified, and the outcomes of this subgroup are not well described. OBJECTIVES: To assess the infarct characteristics at myocardial-tissue level and subsequent clinical outcomes in SMuRF-less STEMIs. METHODS: This multicenter, individual patient-data analysis included 2012 STEMI patients enrolled in four cardiac magnetic resonance (CMR) imaging studies conducted in Austria, Germany, Scotland, and the Netherlands. Unstable patients at time of CMR (e.g. cardiogenic shock/after cardiac arrest) were excluded. SMuRF-less was defined as absence of hypertension, smoking, hypercholesterolemia, and diabetes mellitus. All patients underwent CMR 3(interquartile range [IQR]:2-4) days after infarction to assess left ventricular (LV) volumes and ejection fraction, infarct size and microvascular obstruction (MVO). Clinical endpoints were defined as major adverse cardiovascular events (MACE), including all-cause mortality, re-infarction and heart failure. RESULTS: No SMuRF was identified in 185 patients (9%). These SMuRF-less patients were older, more often male, had lower TIMI risk score and pre-interventional TIMI flow, and less frequently multivessel-disease. SMuRF-less patients did not show significant differences in CMR markers compared to patients with SMuRFs (all p > 0.10). During a median follow-up of 12 (IQR:12-27) months, 199 patients (10%) experienced a MACE. No significant difference in MACE rates was observed between SMuRF-less patients and patients with SMuRFs (8vs.10%, p = 0.39). CONCLUSIONS: In this large individual patient-data pooled analysis of low-risk STEMI patients, infarct characteristics and clinical outcomes were not different according to SMuRF status.

Cardiac Magnetic Resonance Imaging Versus Computed Tomography to Guide Transcatheter Aortic Valve Replacement: A Randomized, Open-Label, Noninferiority Trial.

BACKGROUND: Computed tomography (CT) is recommended for guiding transcatheter aortic valve replacement (TAVR). However, a sizable proportion of TAVR candidates have chronic kidney disease, in whom the use of iodinated contrast media is a limitation. Cardiac magnetic resonance imaging (CMR) is a promising alternative, but randomized data comparing the effectiveness of CMR-guided versus CT-guided TAVR are lacking. METHODS: An investigator-initiated, prospective, randomized, open-label, noninferiority trial was conducted at 2 Austrian heart centers. Patients evaluated for TAVR according to the inclusion criteria (severe symptomatic aortic stenosis) and exclusion criteria (contraindication to CMR, CT, or TAVR, a life expectancy <1 year, or chronic kidney disease level 4 or 5) were randomized (1:1) to undergo CMR or CT guiding. The primary outcome was defined according to the Valve Academic Research Consortium-2 definition of implantation success at discharge, including absence of procedural mortality, correct positioning of a single prosthetic valve, and proper prosthetic valve performance. Noninferiority was assessed using a hybrid modified intention-to-treat/per-protocol approach on the basis of an absolute risk difference margin of 9%. RESULTS: Between September 11, 2017, and December 16, 2022, 380 candidates for TAVR were randomized to CMR-guided (191 patients) or CT-guided (189 patients) TAVR planning. Of these, 138 patients (72.3%) in the CMR-guided group and 129 patients (68.3%) in the CT-guided group eventually underwent TAVR (modified intention-to-treat cohort). Of these 267, 19 patients had protocol deviations, resulting in a per-protocol cohort of 248 patients (121 CMR-guided, 127 CT-guided). In the modified intention-to-treat cohort, implantation success was achieved in 129 patients (93.5%) in the CMR group and in 117 patients (90.7%) in the CT group (between-group difference, 2.8% [90% CI, -2.7% to 8.2%]; P<0.01 for noninferiority). In the per-protocol cohort (n=248), the between-group difference was 2.0% (90% CI, -3.8% to 7.8%; P<0.01 for noninferiority). CONCLUSIONS: CMR-guided TAVR was noninferior to CT-guided TAVR in terms of device implantation success. CMR can therefore be considered as an alternative for TAVR planning. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03831087.

Temporal Trends in Infarct Severity Outcomes in ST-Segment-Elevation Myocardial Infarction: A Cardiac Magnetic Resonance Imaging Study.

Background Severity of myocardial tissue injury is a main determinant of morbidity and death related to ST-segment-elevation myocardial infarction (STEMI). Temporal trends of infarct characteristics at the myocardial tissue level have not been described. This study sought to assess temporal trends in infarct characteristics through a comprehensive assessment by cardiac magnetic resonance imaging at a standardized time point early after STEMI. Methods and Results We analyzed patients with STEMI treated with percutaneous coronary intervention at the University Hospital of Innsbruck who underwent cardiac magnetic resonance imaging between 2005 and 2021. The study period was divided into terciles. Myocardial damage characteristics were assessed using a multiparametric cardiac magnetic resonance imaging protocol within the first week after STEMI and compared between groups. A total of 843 patients with STEMI (17% women) with a median age of 57 (interquartile range, 51-66) years were analyzed. While age, sex, and the clinical risk profile expressed as thrombolysis in myocardial infarction risk score were comparable across the study period, there were differences in guideline-recommended therapies. At the same time, there was no significant change in infarct size (P=0.25), microvascular obstruction (P=0.50), and intramyocardial hemorrhage (P=0.34). Left ventricular remodeling indices and left ventricular ejection fraction remained virtually unchanged (all P>0.05). Major adverse cardiovascular events at 4 (interquartile range, 4-5) months were similar between groups (P=0.36). Conclusions In this magnetic resonance imaging study investigating patients with STEMI treated with primary percutaneous coronary intervention over the past 15 years, no change in infarct severity at the myocardial level has been observed. Clinical research on novel therapeutic approaches to reduce myocardial tissue injury should be a priority.

Improved detection of echocardiographically occult left ventricular thrombi following ST-elevation myocardial infarction.

AIM: The aim of this study was to investigate predictors of transthoracic echocardiography (TTE)-occult left ventricular (LV) thrombi (LVT) and to propose a clinical model for improved detection of TTE-occult LVT post-ST-elevation myocardial infarction (STEMI). Patients with acute STEMI are at significant risk for developing LVT. However, this complication often (up to 65%) remains undetected by using TTE, referred to as TTE-occult LVT. METHODS AND RESULTS: In total, 870 STEMI patients underwent TTE and cardiac magnetic resonance (CMR), the reference method for LVT detection, 3 days after infarction. Clinical (body mass index, peak cardiac troponin T) and echocardiographic [ejection fraction, apical wall motion scores (AWMSs)] predictors were analysed. Primary endpoint was the presence of TTE-occult LVT identified by CMR imaging. From the overall cohort, 37 patients (4%) showed an LVT by CMR. Of these thrombi, 25 (68%) were not identified by TTE. Transthoracic echocardiography-occult thrombi did not significantly differ in volume (1.4 vs. 2.74 cm3), diameter (19.0 vs. 23.3 mm), and number of fragments or shape compared with TTE-apparent LVT (all P > 0.05). For predicting these TTE-occult LVT, the 16-segment AWMS (AWMS16Seg) showed highest validity {area under the curve: 0.91 [95% confidence interval (CI): 0.89-0.93]; P < 0.001}, with an association independent of ejection fraction and 17-segment AWMS (AWMS17Seg) [odds ratio: 1.68 (95% CI: 1.43-1.97); P < 0.001] and clinical (body mass index, peak troponin) and angiographic (culprit lesion, post-interventional thrombolysis in myocardial infarction flow) associates of TTE-occult LVT (all P < 0.05). Dichotomization at AWMS16Seg ≥ 8 (n = 260, 30%) allowed for a detection of all TTE-occult LVT (sensitivity: 100%), with a corresponding specificity of 77%. CONCLUSION: After acute STEMI, AWMS16Seg served as a simple and very robust predictor of TTE-occult LVT. An AWMS16Seg-based algorithm to identify patients for additional CMR imaging offers great potential to optimize detection of TTE-occult LVT following STEMI.

Slice positioning in phase-contrast MRI impacts aortic stenosis assessment.

AIMS: To determine the phase-contrast cardiovascular magnetic resonance imaging (PC-CMR) slice-position above aortic leaflet-attachment-plane (LAP) that provides flow-velocity, -volume and aortic valve area (AVA) measurements with best agreement to invasive and echocardiographic measurements in aortic stenosis (AS). METHODS AND RESULTS: Fifty-five patients with moderate/severe AS underwent cardiac catheterization, transthoracic echocardiography (TTE) and CMR. Overall, 171 image-planes parallel to LAP were measured via PC-CMR between 22 mm below and 24 mm above LAP. AVA via PC-CMR was calculated as flow-volume divided by peak-velocity during systole. Stroke volume (SV) and AVA were compared to volumetric SV and invasive AVA via the Gorlin-formula, respectively. Above LAP, SV by PC-CMR showed no significant dependence on image-plane-position and correlated strongly with volumetry (rho: 0.633, p < 0.001, marginal-mean-difference (MMD): 1 ml, 95 % confidence-interval (CI): -4 to 6). AVA assessed in image-planes 0-10 mm above LAP differed significantly from invasive measurement (MMD: -0.14 cm2, 95 %CI: 0.08-0.21). In contrast, AVA-values by PC-CMR measured 10-20 mm above LAP showed good agreement with invasive determination without significant MMD (0.003 cm2, 95 %CI: -0.09 to 0.09). Within these measurements, a plane 15 mm above LAP resulted in the lowest bias (MMD: 0.02 cm2, 95 %CI:-0.29 to 0.33). SV and AVA via TTE correlated moderately with volumetry (rho: 0.461, p < 0.001; bias: 15 ml, p < 0.001) and cardiac catheterization (rho: 0.486, p < 0.001, bias: -0.13 cm2, p < 0.001), respectively. CONCLUSION: PC-CMR measurements at 0-10 mm above LAP should be avoided due to significant AVA-overestimation compared to invasive determination. AVA-assessment by PC-CMR between 10 and 20 mm above LAP did not differ from invasive measurements, with the lowest intermethodical bias measured 15 mm above LAP.

Prognostic value of pulmonary transit time by cardiac magnetic resonance imaging in ST-elevation myocardial infarction.

OBJECTIVES: To investigate the prognostic value of pulmonary transit time (pTT) determined by cardiac magnetic resonance (CMR) after acute ST-segment-elevation myocardial infarction (STEMI). METHODS: Comprehensive CMR examinations were performed in 207 patients 3 days and 4 months after reperfused STEMI. Functional parameters and infarct characteristics were assessed. PTT was defined as the interval between peaks of gadolinium contrast time-intensity curves in the right and left ventricles in first-pass perfusion imaging. Cox regression models were calculated to assess the association between pTT and the occurrence of major adverse cardiac events (MACE), defined as a composite of death, re-infarction, and congestive heart failure. RESULTS: PTT was 8.6 s at baseline and 7.8 s at the 4-month CMR. In Cox regression, baseline pTT (hazard ratio [HR]: 1.58; 95% CI: 1.12 to 2.22; p = 0.009) remained significantly associated with MACE occurrence after adjustment for left ventricular ejection fraction (LVEF) and cardiac index. The association of pTT and MACE remained significant also after adjusting for infarct size and microvascular obstruction size. In Kaplan-Meier analysis, pTT ≥ 9.6 s was associated with MACE (p < 0.001). Addition of pTT to LVEF resulted in a categorical net reclassification improvement of 0.73 (95% CI: 0.27 to 1.20; p = 0.002) and integrated discrimination improvement of 0.07 (95% CI: 0.02 to 0.13; p = 0.007). CONCLUSIONS: After reperfused STEMI, CMR-derived pTT was associated with hard clinical events with prognostic information independent of and incremental to infarct size and LV systolic function. KEY POINTS: • Pulmonary transit time is the duration it takes the heart to pump blood from the right chambers across lung vessels to the left chambers. • This prospective single-centre study showed inferior outcome in patients with prolonged pulmonary transit time after myocardial infarction. • Pulmonary transit time assessed by magnetic resonance imaging added incremental information to established prognostic markers.

Cardiac magnetic resonance imaging versus computed tomography to guide transcatheter aortic valve replacement: study protocol for a randomized trial (TAVR-CMR).

BACKGROUND: The standard procedure for the planning of transcatheter aortic valve replacement (TAVR) is the combination of echocardiography, coronary angiography, and cardiovascular computed tomography (TAVR-CT) for the exact determination of the aortic valve dimensions, valve size, and implantation route. However, up to 80% of the patients undergoing TAVR suffer from chronic renal insufficiency. Alternatives to reduce the need for iodinated contrast agents are desirable. Cardiac magnetic resonance (CMR) imaging recently has emerged as such an alternative. Therefore, we aim to investigate, for the first time, the non-inferiority of TAVR-CMR to TAVR-CT regarding efficacy and safety end-points. METHODS: This is a prospective, randomized, open-label trial. It is planned to include 250 patients with symptomatic severe aortic stenosis scheduled for TAVR based on a local heart-team decision. Patients will be randomized in a 1:1 fashion to receive a predefined TAVR-CMR protocol or to receive a standard TAVR-CT protocol within 2 weeks after inclusion. Follow-up will be performed at hospital discharge after TAVR and after 1 and 2 years. The primary efficacy outcome is device implantation success at discharge. The secondary endpoints are a combined safety endpoint and a combined clinical efficacy endpoint at baseline and at 1 and 2 years, as well as a comparison of imaging procedure related variables. Endpoint definitions are based on the updated 2012 VARC-2 consensus document. DISCUSSION: TAVR-CMR might be an alternative to TAVR-CT for planning a TAVR procedure. If proven to be effective and safe, a broader application of TAVR-CMR might reduce the incidence of acute kidney injury after TAVR and thus improve outcomes. TRIAL REGISTRATION: The trial is registered at ClinicalTrials.gov (NCT03831087). The results will be disseminated at scientific meetings and publication in peer-reviewed journals.

Prevalence and prognostic impact of mitral annular disjunction in patients with STEMI - A cardiac magnetic resonance study.

BACKGROUND: Mitral annular disjunction (MAD) represents the detachment of the mitral leaflet hinge-point from the ventricular myocardium. Its role in patients with ST-segment-elevation myocardial infarction (STEMI) is unknown. This study aims to investigate the prevalence of MAD by cardiac magnetic resonance imaging (CMR) in STEMI-patients and its association with serious adverse events. METHODS: STEMI-patients (n = 621) underwent CMR 4 days [interquartile range (IQR) 2-5] after percutaneous coronary intervention. Presence and longitudinal extent of MAD were obtained in long-axis cine-images, infarct characteristics in late gadolinium enhancement-images. During a median follow-up time of 366 days (IQR 136-454), patients were observed for the occurrence of major adverse cardiac events (MACE), comprising death, myocardial reinfarction, and congestive heart failure. RESULTS: Overall, 307 patients (49 %) had MAD. Longitudinal MAD-distance was 4.6 ±â€¯1.7 mm and the P3-segment was affected most frequently (n = 262, 85 % of MAD-patients). MAD-patients had a significantly smaller infarct size, lower prevalence of microvascular obstruction, and intramyocardial hemorrhage as well as a higher ejection fraction (all p < 0.03). During follow-up period, MACE occurred in 52 patients (8 %) and did not show significant difference between patients with and without MAD (7 % vs. 9 %, p = 0.424). Cardiovascular death occurred significantly more often in patients without MAD (n = 10, 3.2 % vs. n = 2, 0.7 %, p = 0.021). CONCLUSION: MAD is a rather common finding in patients presenting with STEMI. Patients with MAD had less severe infarct characteristics, however, they were not more commonly affected by MACE. Further confirmation and longer follow-up intervals are necessary to define the exact role of MAD in STEMI patients.

Evolution of Myocardial Tissue Injury: A CMR Study Over a Decade After STEMI.

BACKGROUND: In patients with a first ST-segment elevation myocardial infarction (STEMI), the multi-annual evolution of myocardial tissue injury parameters, as assessed by cardiac magnetic resonance (CMR), has not yet been described. OBJECTIVES: This study examined myocardial tissue injury dynamics over a decade after STEMI. METHODS: Sequential CMR examinations (within the first week after STEMI, and at 4, 12, months, and 9 years thereafter) were conducted in 74 patients with STEMI treated with primary percutaneous coronary intervention. Left ventricular function, infarct size (IS), and microvascular obstruction (MVO) were assessed at all time points. T2∗, T2, and T1 mapping (n = 59) were added at 9-year scan to evaluate the presence of iron and edema within the infarct core, respectively. RESULTS: IS decreased progressively and significantly between all CMR time points (all P < 0.001), with an average reduction rate of 5.8% per year (IQR: 3.5%-8.8%) and a relative reduction of 49% (IQR: 39%-76%) over a decade. MVO was present in 61% of patients at baseline, but was not present at the follow-up examinations. At 9-year CMR, 17 of 59 (29%) patients showed iron deposition within the infarct core, whereas 82% had persistent edema. Persistent iron and edema were associated with greater IS on any occasion (all P < 0.001), as well as the presence of MVO (P < 0.001). Patients with persistent iron and edema showed a lower relative regression of IS (P = 0.005 and P = 0.032, respectively) and greater end-systolic volumes over a decade (all P < 0.012 and P > 0.023, respectively). A T1 hypointense infarct core without evidence of T2∗ iron deposition (14 of 59 [24%] patients) was attributed to lipomatous metaplasia of the infarct. CONCLUSIONS: The evolution of IS is a dynamic process that extends well beyond the first few months after STEMI. Persistence of iron and edema within the infarct core occurs up to a decade after STEMI and is associated with initial infarct severity and poor infarct healing.

Association between inflammation and left ventricular thrombus formation following ST-elevation myocardial infarction.

BACKGROUND: Current evidence suggests a link between the inflammatory state and left ventricular (LV) thrombus formation following ST-elevation myocardial infarction (STEMI). However, a comprehensive study investigating the association between inflammatory biomarkers and LV thrombus diagnosed by cardiac magnetic resonance (CMR) is lacking. METHODS: We studied 309 patients with acute STEMI treated with primary percutaneous coronary intervention (pPCI) from the prospective MARINA-STEMI cohort study. Concentrations of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), white blood cell count (WBCc), fibrinogen and D-dimer were measured two days after STEMI. Infarct characteristics and presence of LV thrombi were assessed with the use of contrast-enhanced CMR at a median of 4 (interquartile range [IQR] 3-5) days after pPCI. RESULTS: In total, 309 STEMI patients (18% female) with a median age of 57 (IQR 52-65) years were included. A LV thrombus was observed in 8% (n = 24) of the overall cohort and in 15% of patients with an anterior STEMI. Hs-CRP (OR 2.16, 95% CI 1.54-3.02, p < 0.001), IL-6 (OR 2.38, 95% CI 1.48-3.81, p < 0.001) and fibrinogen levels (OR 2.05, 95% CI 1.40-3.00, p < 0.001) were significantly associated with presence of LV thrombus. Among all assessed inflammatory biomarkers, only hs-CRP was independently associated with LV thrombus after adjustment for markers of inflammation and CMR parameters (OR 1.77, 95% CI 1.21-2.59, p = 0.004). CONCLUSION: In patients with STEMI treated with pPCI, inflammatory markers (hs-CRP, IL-6 and fibrinogen) are associated with the presence of LV thrombus. However, only hs-CRP was independently associated with the occurrence of LV thrombi, highlighting the key role of CRP as clinical risk marker for LV thrombus formation in STEMI patients treated with pPCI.