Effect of Aspiration Thrombectomy on Microvascular Obstruction in NSTEMI Patients : The TATORT-NSTEMI Trial

Background

Aspiration thrombectomy in ST-segment elevation myocardial infarction is recommended by current guidelines based on several randomized trials. There are no trials assessing thrombectomy in non–ST-segment elevation myocardial infarction (NSTEMI) patients.

Objectives

The TATORT-NSTEMI (Thrombus Aspiration in Thrombus Containing Culprit Lesions in Non–ST-Elevation Myocardial Infarction) trial sought to assess the effect of aspiration thrombectomy on microvascular injury in patients with NSTEMI compared with standard percutaneous coronary intervention (PCI).

Methods

This prospective, controlled, multicenter study randomized 440 patients to adjunctive thrombectomy (n = 221) compared with conventional PCI (n = 219) in NSTEMI patients with thrombus-containing lesions. The primary endpoint of the extent of microvascular obstruction (MO) in the percentage of left ventricular mass (%LV) was assessed by cardiac magnetic resonance imaging within 4 days. Secondary endpoints included infarct size, myocardial salvage index, and angiographic parameters including myocardial blush grade and Thrombolysis In Myocardial Infarction flow grade. The combined clinical endpoint consisted of death, reinfarction, target vessel revascularization, and new congestive heart failure within 6 months.

Results

The primary endpoint of MO was not different between the thrombectomy and the standard PCI group with 2.0%LV (interquartile range [IQR]: 0.8 to 4.1) versus 1.4%LV (IQR: 0.7 to 2.6) (p = 0.17). Similarly, no significant differences were observed for infarct size (8.6%LV; IQR: 4.0 to 14.7 vs. 7.4%LV; IQR: 4.1 to 13.1; p = 0.46), myocardial salvage index (63.3; IQR: 35.4 to 87.2 vs. 65.6; IQR: 46.9 to 82.6; p = 0.45), or angiographic parameters such as blush grade (p = 0.63) and Thrombolysis In Myocardial Infarction flow grade (p = 0.66). Clinical follow-up at 6 months revealed no differences in the combined clinical endpoints (p = 0.22).

Conclusions

Aspiration thrombectomy in conjunction with PCI in NSTEMI with a thrombus-containing lesion does not lead to a reduction in MO. (Thrombus Aspiration in Thrombus Containing Culprit Lesions in Non-ST-Elevation Myocardial Infarction [TATORT-NSTEMI]; NCT01612312).     

Association of aortic stiffness with biomarkers of myocardial wall stress after myocardial infarction

Background

Aortic pulse wave velocity (PWV) was linked to LV-geometry and -function in patients with kidney disease and non-ischemic cardiomyopathy. The role of aortic compliance after acute STEMI is so far unknown. In the present study, we prospectively investigated the relationship of increased aortic stiffness with biomarkers of myocardial wall stress 4 months after STEMI.

Methods

48 STEMI patients who were reperfused by primary coronary angioplasty underwent cardiovascular magnetic resonance (CMR) at baseline and at 4-month follow-up. The CMR protocol comprised cine-CMR as well as gadolinium contrast-enhanced CMR. Aortic PWV was determined by velocity-encoded, phase-contrast CMR. Blood samples were routinely drawn at baseline and follow-up to determine N-terminal pro-B-type natriuretic peptide (NT-proBNP). In a subgroup of patients, mid-regional pro-adrenomedullin (MR-proADM) and mid-regional pro-A-type natriuretic peptide (MR-proANP) levels were determined.

Results

Patients with a PWV above median (> 7.0 m/s) had significantly higher NT-proBNP, MR-proADM and MR-proANP concentrations at 4-month follow-up than patients with a PWV below median (all p < 0.02). PWV showed moderate to good correlation with NT-proBNP, MR-proAMD and MR-proANP levels 4 months after STEMI (all p < 0.05). Multivariate analysis revealed PWV, beside myocardial infarct size, as an independent predictor of 4-month NT-proBNP levels after correction for age, creatinine and LV ejection fraction (model r: 0.781, p < 0.001).

Conclusion

Aortic stiffness is directly associated with biomarkers of myocardial wall stress 4 months after reperfused STEMI, suggesting a role for aortic stiffness in chronic LV-remodelling.     

Impact of Microvascular Obstruction on the Assessment of Coronary Flow Reserve,Index of Microcirculatory Resistance,and Fractional Flow Reserve After ST-Segment Elevation Myocardial Infarction

Background

Invasive assessment of coronary physiology (IACP) offers important prognostic insights in ST-segment elevation myocardial infarction (STEMI) but the dynamics of coronary recovery are poorly understood.

Objectives

This study sought to examine the evolution of coronary flow reserve (CFR), index of microcirculatory resistance (IMR), ratio of distal coronary pressure (Pd) to mean aortic pressure (Pa), and fractional flow reserve (FFR) in patients undergoing primary percutaneous coronary intervention (PPCI).

Methods

82 patients with STEMI underwent IACP at PPCI. Repeat IACP was performed in 61 patients (74%) at day 1 and in 46 patients (56%) at 6 months. Contrast-enhanced cardiac magnetic resonance imaging (CMR) was performed in 45 patients (55%) at day 1 and in 41 patients (50%) at 6 months. Changes in IACP were compared between patients with and without microvascular obstruction (MVO) on CMR.

Results

MVO was present in 21 of 45 patients (47%). Patients with MVO had lower CFR at PPCI and day 1 (p < 0.05) and a trend toward higher IMR values (p = 0.07). At 6 months, CFR and IMR were not significantly different between the groups. Baseline flow and Pd/Pa remained stable over time but FFR reduced significantly between PPCI and 6 months (p = 0.008); this reduction was mainly observed in patients with MVO (p = 0.006) but not in those without MVO (p = 0.21).

Conclusions

In PPCI-treated patients with STEMI, coronary microcirculation begins to recover within 24 h and recovery progresses further by 6 months. FFR significantly reduces from baseline to 6 months. The presence of MVO indicates a highly dysfunctional microcirculation.     

Long-Term Incremental Prognostic Value of Cardiovascular Magnetic Resonance After ST-Segment Elevation Myocardial Infarction: A Study of the Collaborative Registry on CMR in STEMI

Objectives

This study sought to investigate whether early post-infarction cardiac magnetic resonance (CMR) parameters provide additional long-term prognostic value beyond traditional outcome predictors in ST-segment elevation myocardial infarction (STEMI) patients.

Cardiac Magnetic Resonance Myocardial Feature Tracking for Optimized Prediction of Cardiovascular Events Following Myocardial Infarction

Objectives

The aims of the study were to assess the prognostic significance of cardiac magnetic resonance myocardial feature tracking (CMR-FT) in a large multicenter study and to evaluate the most potent CMR-FT predictor of hard clinical events following myocardial infarction (MI).

A mismatch index based on the difference between measured left ventricular ejection fraction and that estimated by infarct size at three months following reperfused acute myocardial infarction

Background and Aim

The reduction of left ventricular ejection fraction (LVEF) following ST-segment elevation myocardial infarction (STEMI) is a result of infarcted myocardium and may involve dysfunctional but viable myocardium. An index that may quantitatively determine whether LVEF is reduced beyond the expected value when considering only infarct size (IS) has previously been presented based on cardiac magnetic resonance (CMR). The purpose of this study was to introduce the index based on the electrocardiogram (ECG) and compare indices based on ECG and CMR.

Method and Results

In 55 patients ECG and CMR were obtained 3 months after STEMI treated with primary percutaneous coronary intervention. Significant, however moderate inverse relationships were found between measured LVEF and IS. Based on IS and LVEF an IS estimated LVEF was derived and an MI–LVEF mismatch index was calculated as the difference between measured LVEF and IS estimated LVEF. In 41 (74.5%) of the patients there was agreement between the ECG and CMR indices in regards to categorizing indices as > 10 or ≤ 10 and generally no significant difference was detected, mean difference of 1.26 percentage points (p = 0.53).

Conclusion

The study found an overall good agreement between MI–LVEF mismatch indices based on ECG and CMR. The MI–LVEF mismatch index may serve as a tool to identify patients with potentially reversible dysfunctional but viable myocardium, but future studies including both ECG and CMR are needed.     

Prognostic Significance of Remote Myocardium Alterations Assessed by Quantitative Noncontrast T1 Mapping in ST-Segment Elevation Myocardial Infarction

Objectives

This study assessed the prognostic significance of remote zone native T1 alterations for the prediction of clinical events in a population with ST-segment elevation myocardial infarction (STEMI) who were treated by primary percutaneous coronary intervention (PPCI) and compared it with conventional markers of infarct severity.

Osteoprotegerin in ST-elevation myocardial infarction: Prognostic impact and association with markers of myocardial damage by magnetic resonance imaging

Background/Objectives

For osteoprotegerin (OPG), a cytokine of the tumor necrosis factor superfamily, the prognostic impact in stable coronary artery disease and acute coronary syndromes has been shown recently. In acute ST-elevation myocardial infarction (STEMI) data on the correlation to myocardial damage by cardiac magnetic resonance imaging (CMR) or clinical outcome are lacking.

Methods

We studied 221 consecutive patients with acute STEMI undergoing primary percutaneous coronary intervention (PCI) within 12 h after symptom onset. Serum levels of OPG were determined from samples collected before PCI (OPG0), at 24 (OPG1) and 48 h (OPG2) after reperfusion. CMR studies for assessment of infarct size, reperfusion injury/microvascular obstruction and myocardial salvage were performed within one week after infarction. Long-term clinical follow-up for major adverse cardiovascular events (MACE), defined as death, myocardial infarction, or new onset of congestive heart failure, was performed 18.2 (interquartile range of 9.2–21.2) months after the index event.

Results

OPG levels ≥ 75th percentile were associated with significantly larger infarcts, lower myocardial salvage index and greater extent of microvascular obstruction in CMR as compared to OPG levels < 75th percentile. The MACE rate for patients with OPG levels in the highest quartile was also significantly higher. In a multivariable model adjusted for known risk factors, OPG1 as a continuous variable was independently predictive for MACE.

Conclusion

OPG serum levels collected 24 h after infarction are independent predictors of MACE in acute STEMI patients. High OPG levels are associated with a greater extent of myocardial damage and lower myocardial salvage by CMR.     

Angiographic assessment of myocardial perfusion in Tako-Tsubo syndrome

Objectives

To angiographically assess myocardial perfusion in patients with Tako-Tsubo syndrome (TTS) in comparison with control individuals and patients with ST-elevation myocardial infarction (STEMI).

Background

Coronary microvascular dysfunction has been proposed as the pathophysiological mechanism underlying TTS.

Methods

We retrospectively selected consecutive TTS patients showing typical left ventricular (LV) apical dysfunction admitted to our Department in the period 2007–2011 (n = 25). We also enrolled an age and gender-matched control group showing normal coronary arteries (CTR, n = 25), patients with STEMI undergoing primary percutaneous intervention with myocardial reperfusion (SR, n = 25) or microvascular obstruction (SMVO, n = 25). TIMI flow, TIMI frame count (TFC) and both qualitative and quantitative myocardial blush grade in LV apex were assessed. Specifically, myocardial perfusion was quantitatively evaluated using ‘Quantitative Blush Evaluator’ (QuBE), an open source software previously validated in the setting of STEMI.

Results

In TTS, TIMI flow on the LAD was significantly lower and TFC significantly higher compared to CTR and SR (p = 0.008 for both), while it did not significantly differ compared to SMVO (p = 0.06). In TTS, MBG was significantly lower than that in CTR and SR (p = 0.001 for both), while it was significantly higher than that in SMVO (p < 0.001). In TTS, QuBE score was significantly lower than that in CTR and SR (p = 0.001 for both) and higher than in SMVO (p = 0.02).

Conclusions

Our data indicate that myocardial perfusion assessed during angiography is more impaired in patients with TTS than in patients with STEMI exhibiting myocardial reperfusion, while it is less impaired than in patients with STEMI exhibiting MVO.     

Cardiovascular magnetic resonance-derived intramyocardial hemorrhage after STEMI: Influence on long-term prognosis,adverse left ventricular remodeling and relationship with microvascular obstruction

Background

T2 weighted cardiovascular magnetic resonance (CMR) can detect intramyocardial hemorrhage (IMH) after ST-elevation myocardial infarction (STEMI). The long-term prognostic value of IMH beyond a comprehensive CMR assessment with late enhancement (LE) imaging including microvascular obstruction (MVO) is unclear. The value of CMR-derived IMH for predicting major adverse cardiac events (MACE) and adverse cardiac remodeling after STEMI and its relationship with MVO was analyzed.

Methods

CMR including LE and T2 sequences was performed in 304 patients 1 week after STEMI. Adverse remodeling was defined as dilated left ventricular end-systolic volume indexes (dLVESV) at 6 months CMR.

Results

During a median follow-up of 140 weeks, 47 MACE (10 cardiac deaths, 16 myocardial infarctions, 21 heart failure episodes) occurred. Predictors of MACE were ejection fraction (HR .95 95% CI [.93–.97], p = .001, per %) and IMH (HR 1.17 95% CI [1.03–1.33], p = .01, per segment). The extent of MVO and IMH significantly correlated (r = .951, p < .0001). dLVESV was present in 40% of patients. CMR predictors of dLVESV were: LVESV (OR 1.11 95% CI [1.07–1.15], p < .0001, per ml/m²), infarct size (OR 1.05 95% CI [1.01–1.09], p = .02, per %) and IMH (OR 1.54 95% CI [1.15–2.07], p = .004, per segment). Addition of T2 information did not improve the LE and cine CMR-model for predicting MACE (.744 95% CI [.659–.829] vs. .734 95% CI [.650–.818], p = .6) or dLVESV (.914 95% CI [.875–.952] vs. .913 95% CI [.875–.952], p = .9).

Conclusions

IMH after STEMI predicts MACE and adverse remodeling. Nevertheless, with a strong interrelation with MVO, the addition of T2 imaging does not improve the predictive value of LE-CMR.     

Impact of Non-Infarct-Related Artery Disease on Infarct Size and Outcomes (from the CRISP-AMI Trial)

Background

Non-infarct-related artery (non-IRA) disease is prevalent in patients with ST-segment elevation myocardial infarction (STEMI). We aimed to assess the impact of non-IRA disease on infarct size and clinical outcomes in patients with acute STEMI.

Methods

The Counterpulsation to Reduce Infarct Size Pre-PCI Acute Myocardial Infarction (CRISP-AMI) trial randomized patients to intra-aortic balloon counterpulsation (IABC) vs no IABC prior to percutaneous coronary intervention in patients with acute STEMI. Infarct size (% left ventricular mass) at 3-5 days post percutaneous coronary intervention and 6-month clinical outcomes were compared between patients with and without non-IRA disease (defined as ≥50% stenosis in at least one non-IRA).

Results

A total of 324 (96.1%) patients had anterior STEMI, of whom 34.9% had non-IRA disease. There was no difference in infarct size (% left ventricular mass) between patients with and without non-IRA disease (median 39% vs 39%; P = .73). At 6 months, there was no difference in rates of recurrent myocardial infarction (0.9% vs 0.9%; P = .78), major Thrombolysis In Myocardial Infarction bleeding (0.9% vs 0.5%; P = .77), or all-cause death (3.5% vs 2.4%; P = .61) in patients with and without non-IRA disease, respectively. Patients with non-IRA disease had a higher rate of new/worsening heart failure with hospitalization (8.8% vs 1.9%; P = .0050).

Conclusions

More than one-third of patients with anterior STEMI in the CRISP-AMI study had non-IRA disease. These patients had similar infarct sizes and rates of recurrent myocardial infarction, major bleeding, and all-cause death. Patients with non-IRA disease did have a higher rate of new/worsening heart failure with hospitalization. Further study is needed to understand the mechanisms of outcomes of patients with non-IRA disease.     

Positive effect of intravenous iron-oxide administration on left ventricular remodelling in patients with acute ST-elevation myocardial infarction – A cardiovascular magnetic resonance (CMR) study

Objectives

This study investigated the safety profile and potential “therapeutic” effect of intravenous ultrasmall superparamagnetic iron-oxide (USPIO)-based iron administration regarding infarct healing in patients with ST-elevation myocardial infarction (STEMI). USPIO-administration was recently shown to enable an improved characterization of myocardial infarct pathology in acute STEMI patients.

Materials and Methods

Seventeen study patients (IRON, 54 ± 9 yrs, 88% male) and 22 matched controls (CONTROL, 57 ± 9 yrs, 77% male) both with primary reperfused STEMI underwent multi-parametric CMR studies in the first week and three months after acute MI. Only IRON patients received a single intravenous bolus of 510 mg elemental iron as ferumoxytol (Feraheme^TM) within four days following acute MI.

Results

Three months later, all patients were alive and there were no adverse cardiac events. Significant improvement in left ventricular (LV) ejection fraction (IRON: 53 ± 10% to 59 ± 9%, p = 0.002; CONTROL: 54 ± 6% to 57 ± 10%, p = 0.005) as well as shrinkage of infarct size were seen in both groups at follow-up. There was a more pronounced decrease in infarct size in the IRON group (IRON: − 10.3 ± 5.4% vs. CONTROL: − 7.0 ± 8.4%, p = 0.050) in addition to a significant decrease in both endocardial extent and prevalence of transmural infarctions in IRON but not in CONTROL patients. A significant decrease in LV end systolic volume was only seen in the IRON group (71 ± 25 mL to 59 ± 25 mL, p = 0.002).

Conclusions

Intravenous iron administration in acute STEMI patients seems to be associated with an improved infarct healing and a beneficial global left ventricular remodelling. These findings together with the good safety profile make USPIO-based iron administration a promising future candidate as a “diagnostic” and “therapeutic” adjunctive solution in acute MI management.     

Prognostic value of neutrophil/lymphocyte ratio in patients with ST-elevated myocardial infarction undergoing primary coronary intervention: A prospective,multicenter study

Objective

The pre-procedural neutrophil to lymphocyte ratio (N/L) is associated with adverse outcomes among patients with coronary artery disease but its prognostic value in ST-segment elevation myocardial infarction (STEMI) has not been fully investigated. This study evaluated the relations between pre-procedural N/L ratio and the in-hospital and long-term outcomes in STEMI patients undergoing primary percutaneous coronary intervention (PCI).

Methods

A total of 682 STEMI patients presented within the first 6 h of symptom onset were enrolled and stratified according to tertiles of N/L ratio based on the blood samples obtained in the emergency room upon admission.

Results

The mean follow-up period was 43.3 months (1–131 months). In-hospital in-stent thrombosis, non-fatal myocardial infarction, and cardiovascular mortality increased as the N/L tertile ratio increased (p < 0.001, p < 0.001, p = 0.003, respectively). Long-term in-stent thrombosis, non-fatal myocardial infarction and cardiovascular mortality also increased as the N/L ratio increased (p < 0.001, p < 0.001, p = 0.002, respectively). On multivariate analysis, N/L ratio remained an independent predictor for both in-hospital (OR 1.189, 95% CI 1.000–1.339; p < 0.001) and long-term major (OR 1.228, 95% CI 1.136–1.328; p < 0.001) adverse cardiac events.

Conclusion

The N/L ratio was an independent predictor of both in-hospital and long-term adverse outcomes among STEMI patients undergoing primary PCI. Our findings suggest that this inexpensive, universally available hematological marker may be incorporated into the current established risk assessment model for STEMI.     

Late Gadolinium Enhancement in Cardiac Transplant Patients Is Associated With Adverse Ventricular Functional Parameters and Clinical Outcomes

Background

Heart transplant recipients (HTRs) experience multiple cardiac complications, many of which might produce myocardial fibrosis. Cardiovascular magnetic resonance imaging (CMR) can image myocardial fibrosis using late gadolinium enhancement (LGE) imaging. We hypothesized that the presence and volume of LGE in heart transplant recipients correlates with left ventricular (LV) functional parameters and clinical outcomes.

Methods

Thirty-eight stable HTRs underwent a CMR study and clinical follow-up.

Results

In 38 stable HTRs, LGE was seen in 19 patients (50%), of which 15 (79%) had a nonischemic pattern and 4 (21%) had an ischemic pattern. LGE volume was associated with reduced LV ejection fraction (EF) (R² = 0.57; P = 0.001) and increased LV end-diastolic volume (R² = 0.59; P = 0.001). The presence of LGE was associated with cardiovascular death or hospitalization within the next year (P = 0.04), and patients who died or were hospitalized had more LGE than those that were not hospitalized (15 g vs 7 g; P = 0.03).

Conclusions

LGE is common in HTR and is associated with adverse ventricular remodelling and adverse clinical outcomes. LGE might be a useful noninvasive approach to monitor graft disease in asymptomatic patients after heart transplant.     

Stent Thrombosis in New-Generation Drug-Eluting Stents in Patients With STEMI Undergoing Primary PCI : A Report From SCAAR

Background

Some concerns still have not been resolved about the long-term safety of drug-eluting stents (DES) in patients with acute STEMI.

Objectives

The aim of this study was to evaluate the stent thrombosis (ST) rate up to 3 years in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention (PCI) with new-generation drug-eluting stents (n-DES) compared with bare-metal stents (BMS) and old-generation drug-eluting stents (o-DES) enrolled in the SCAAR (Swedish Coronary Angiography and Angioplasty Registry).

Methods

From January 2007 to January 2013, 34,147 patients with STEMI were treated by PCI with n-DES (n = 4,811), o-DES (n = 4,271), or BMS (n = 25,065). The risks of early/late (up to 1 year) and very late definite ST (after 1 year) were estimated.

Results

Cox regression landmark analysis showed a significantly lower risk of early/late ST in patients treated with n-DES (hazard ratio [HR]: 0.65; 95% confidence interval [CI]: 0.43 to 0.99; p = 0.04) and o-DES (HR: 0.60; 95% CI: 0.41 to 0.89; p = 0.01) compared with the BMS group. The risk of very late ST was similar between the n-DES and BMS groups (HR: 1.52; 95% CI: 0.78 to 2.98; p = 0.21), whereas a higher risk of very late ST was observed with o-DES compared with BMS (HR: 2.88; 95% CI: 1.70 to 4.89; p < 0.01).

Conclusions

Patients treated with n-DES have a lower risk of early/late ST than patients treated with BMS. The risk of very late ST is low and comparable between n-DES and BMS up to 3 years of follow-up, whereas o-DES treatment is associated with an increased risk of very late ST. The current STEMI guidelines might require an update in light of the results of this and other recent studies.     

Distal protection device aggravated microvascular obstruction evaluated by cardiac MR after primary percutaneous intervention for ST-elevation myocardial infarction

Background

Protection of distal embolization by balloon occlusion and thrombus aspiration has not improved microvascular circulation nor decreased myocardial injury during primary percutaneous intervention (PCI) for ST-elevation myocardial infarction (STEMI) in randomized trials. In a prospective randomized trial, we investigated the mechanism of the poor effect of distal protection and thrombus aspiration (DP–TA) in 126 patients with STEMI.

Methods

Patients with first-diagnosed STEMI were randomly assigned to DP–TA pretreatment or conventional PCI (c-PCI). Primary endpoint was reduced left ventricular end-diastolic volume (LVEDV) measured by MRI at post-PCI and 6 months after PCI. Secondary end points were infarct ratio (infarct size to entire LV size) by delayed enhancement (DE), area at risk (AAR) ratio (AAR to entire LV size) by T2 high signal, microvascular occlusion index (MVO) ratio (MVO to entire LV size) by DE, and myocardial salvage index (MSI: (AAR − infarct size) ∗ 100 / AAR) using cardiac magnetic resonance imaging (MRI) within 3 days after PCI.

Results

Baseline characteristics of the patients including cardiovascular risk factors and lesion characteristics were similar between the two groups. DT–PA failed to improve LV remodeling at 6 months (LVEDV 140 ± 39 vs 133 ± 37 in c-PCI group, p = 0.418). Infarct ratio, AAR ratio and MSI were not statistically different between DP–TA group and c-PCI group. However, MVO ratio was significantly larger in DP–TA group than in c-PCI group (2.4 ± 2.7 vs 1.1 ± 1.9, p = 0.045).

Conclusion

DP–TA was potentially hazardous in primary PCI for STEMI by increasing MVO. DP–TA should not be used in STEMI.     

Prognostic implications of quantitative evaluation of baseline Q-wave width in ST-segment elevation myocardial infarction

Objectives

To evaluate quantitative relationships between baseline Q-wave width and 90-day outcomes in ST-segment elevation myocardial infarction (STEMI).

Background

Baseline Q-waves are useful in predicting clinical outcomes after MI.

Methods

3589 STEMI patients were assessed from a multi-centre study.

Results

1156 patients of the overall cohort had pathologic Q-waves. The 90-day mortality and the composite of mortality, congestive heart failure (CHF), or cardiogenic shock (p < 0.001 for both outcomes) rose as Q-wave width increased. After adapting a threshold ≥ 40 ms for inferior and ≥ 20 ms for lateral/apical MI in all patients (n = 3065) with any measureable Q-wave we found hazard ratios (HR) for mortality (HR: 2.44, 95% confidence interval (CI) (1.54–3.85), p < 0.001) and the composite (HR: 2.32, 95% CI (1.70–3.16), p < 0.001). This improved reclassification of patients experiencing the composite endpoint versus the conventional definition (net reclassification index (NRI): 0.23, 95% CI (0.09-0.36), p < 0.001) and universal MI definition (NRI: 0.15, 95% CI (0.02–0.29), p = 0.027).

Conclusions

The width of the baseline Q-wave in STEMI adds prognostic value in predicting 90-day clinical outcomes. A threshold of ≥ 40 ms in inferior and ≥ 20 ms for lateral/apical MI enhances prognostic insight beyond current criteria.     

Myocardial scar characteristics based on cardiac magnetic resonance imaging is associated with ventricular tachyarrhythmia in patients with ischemic cardiomyopathy

Objectives

We hypothesized that myocardial scar characterization using cardiac magnetic resonance imaging (CMR) may be associated with the occurrence of ventricular tachyarrhythmia (VT), appropriate implantable cardioverter-defibrillator (ICD) therapy and mortality.

Background

Since a minority of patients with prophylactic ICD implantation receive appropriate ICD therapy, there is a need for more effective risk stratification for primary prevention in patients with ischemic cardiomyopathy.

Methods and results

In 99 patients with ischemic cardiomyopathy, CMR was performed prior to ICD implantation. We assessed if CMR indices (cardiac mass, LVEF) and CMR scar characteristics (infarct core mass, peri-infarction mass and the ratio's between left ventricular mass, infarct core mass and peri-infarction mass) were associated with outcome. The primary endpoint was sustained VT and/or appropriate ICD therapy. The secondary endpoint was all-cause mortality. During a median follow-up of 5.4 years (IQR 4.5–6.6 years), 34 patients reached the primary end-point (17 appropriate ICD shocks) and 26 patients died. In multivariable Cox regression analysis, peri-infarction to core-infarction ratio (HR 2.01, 95%CI: 1.17–3.44, p = 0.01) was independently and significantly associated with the primary endpoint, whereas NYHA-class and lower LVEF were not. Conversely, age (HR 1.06, 95% CI: 1.01–1.12, p = 0.02) and lower LVEF (HR 0.95, 95% CI: 0.91–1.00, p = 0.04) were independently associated with all-cause mortality, mainly due to heart failure.

Conclusion

A relatively large peri-infarction mass is associated with sustained VT and/or appropriate ICD therapy, whereas age and lower LVEF are associated with mortality. CMR based tissue characterization could aid in the prediction of specific outcome measures and in clinical decision making.     

Prognostic value of cardiovascular magnetic resonance in patients with suspected arrhythmogenic right ventricular cardiomyopathy

Background

Early recognition and accurate risk stratification are important in the management of arrhythmogenic right ventricular cardiomyopathy (ARVC). Identification of predictors of outcome by cardiovascular magnetic resonance (CMR) in patients undergoing evaluation for ARVC is limited. We investigated the predictive value of morphological abnormalities detected by CMR for major clinical events in patients with suspected ARVC.

Methods

We performed a longitudinal study on 369 consecutive patients with at least one criterion for ARVC. Abnormal CMR was defined by the presence of one of the following: increased right ventricular (RV) volumes, reduced RV ejection fraction, RV regional wall motion abnormalities, myocardial fatty infiltration, and myocardial fibrosis. The end-point was a composite of cardiac death, sustained ventricular tachycardia, ventricular fibrillation, and appropriate ICD discharge.

Results

Twenty patients met the composite end-point over a mean follow-up of 4.3 ± 1.5 years. An abnormal CMR was an independent predictor of outcomes (p < 0.001). The presence of multiple abnormalities heralded a particular high risk of events (HR 23.0, 95% CI 5.7–93.2, p < 0.001 for 2 abnormalities; HR 35.8, 95% CI 9.7–132.6, p < 0.001 for 3 or more abnormalities). The positive predictive value of an abnormal CMR study was 21.0% for an adverse event, whilst the negative predictive value of a normal CMR study was 98.8% over the follow-up period.

Conclusions

CMR provides important prognostic information in patients under evaluation for ARVC. A normal study portends a good prognosis. Conversely, the presence of multiple abnormalities identifies a high risk group of patients who may benefit from ICD implantation.     

The relationship between the contralateral collateral supply and myocardial viability on cardiovascular magnetic resonance: Can the angiogram predict functional recovery?

Background

A collateral circulation which supplies a myocardial territory, subtended by a chronic total occlusion (CTO), may be observed at invasive coronary angiography. The prognostic and protective role of such collateralisation is well demonstrated suggesting that a good collateral circulation may be a predictor of myocardial viability, but current evidence is discrepant. The aim of this study is to assess the relationship between collateralisation from the contralateral epicardial vessels and myocardial viability by cardiovascular magnetic resonance (CMR).

Method

Consecutive patients with CTO having had both CMR and invasive coronary angiography were retrospectively identified. The collateral circulation was graded with the Cohen and Rentrop classification. CMR images were graded per segment for wall motion (1: normal/hyperkinetic, 2: hypokinetic, 3: akinetic, or 4: dyskinetic) and wall motion score index (WMSI) was calculated. The segmental transmurality of late gadolinium enhancement was scored as 1 (0%), 2 (1–25%), 3 (26–50%), 4 (51–75%) and 5 (76–100%).

Results

A good collateral circulation was more likely to supply viable myocardium (p = 0.01). There was no relationship between collateral circulation supply and wall motion score index (WMSI), however, increasing transmurality of LGE was significantly associated with higher mean WMSI representing increasing dysfunctional myocardium (p < 0.001).

Conclusion

The presence of collateral coronary circulation at angiography predicts the presence of viability on cardiovascular MRI, with a gradation of greater viability associated with improving Rentrop grade. A collateral circulation at angiography should, therefore, prompt more formal assessment of viability and consideration of revascularisation in order for the patient to obtain the associated functional and prognostic improvement.