The influence of microvascular injury on native T1 and T2* relaxation values after acute myocardial infarction: implications for non-contrast-enhanced infarct assessment.

OBJECTIVES: Native T1 mapping and late gadolinium enhancement (LGE) imaging offer detailed characterisation of the myocardium after acute myocardial infarction (AMI). We evaluated the effects of microvascular injury (MVI) and intramyocardial haemorrhage on local T1 and T2* values in patients with a reperfused AMI. METHODS: Forty-three patients after reperfused AMI underwent cardiovascular magnetic resonance imaging (CMR) at 4 [3-5] days, including native MOLLI T1 and T2* mapping, STIR, cine imaging and LGE. T1 and T2* values were determined in LGE-defined regions of interest: the MI core incorporating MVI when present, the core-adjacent MI border zone (without any areas of MVI), and remote myocardium. RESULTS: Average T1 in the MI core was higher than in the MI border zone and remote myocardium. However, in the 20 (47%) patients with MVI, MI core T1 was lower than in patients without MVI (MVI 1048±78ms, no MVI 1111±89ms, p=0.02). MI core T2* was significantly lower in patients with MVI than in those without (MVI 20 [18-23]ms, no MVI 31 [26-39]ms, p<0.001). CONCLUSION: The presence of MVI profoundly affects MOLLI-measured native T1 values. T2* mapping suggested that this may be the result of intramyocardial haemorrhage. These findings have important implications for the interpretation of native T1 values shortly after AMI. KEY POINTS: • Microvascular injury after acute myocardial infarction affects local T1 and T2* values. • Infarct zone T1 values are lower if microvascular injury is present. • T2* mapping suggests that low infarct T1 values are likely haemorrhage. • T1 and T2* values are complimentary for correctly assessing post-infarct myocardium.

Strain analysis in CRT candidates using the novel segment length in cine (SLICE) post-processing technique on standard CMR cine images.

OBJECTIVES: Although myocardial strain analysis is a potential tool to improve patient selection for cardiac resynchronization therapy (CRT), there is currently no validated clinical approach to derive segmental strains. We evaluated the novel segment length in cine (SLICE) technique to derive segmental strains from standard cardiovascular MR (CMR) cine images in CRT candidates. METHODS: Twenty-seven patients with left bundle branch block underwent CMR examination including cine imaging and myocardial tagging (CMR-TAG). SLICE was performed by measuring segment length between anatomical landmarks throughout all phases on short-axis cines. This measure of frame-to-frame segment length change was compared to CMR-TAG circumferential strain measurements. Subsequently, conventional markers of CRT response were calculated. RESULTS: Segmental strains showed good to excellent agreement between SLICE and CMR-TAG (septum strain, intraclass correlation coefficient (ICC) 0.76; lateral wall strain, ICC 0.66). Conventional markers of CRT response also showed close agreement between both methods (ICC 0.61-0.78). Reproducibility of SLICE was excellent for intra-observer testing (all ICC ≥0.76) and good for interobserver testing (all ICC ≥0.61). CONCLUSIONS: The novel SLICE post-processing technique on standard CMR cine images offers both accurate and robust segmental strain measures compared to the 'gold standard' CMR-TAG technique, and has the advantage of being widely available. KEY POINTS: • Myocardial strain analysis could potentially improve patient selection for CRT. • Currently a well validated clinical approach to derive segmental strains is lacking. • The novel SLICE technique derives segmental strains from standard CMR cine images. • SLICE-derived strain markers of CRT response showed close agreement with CMR-TAG. • Future studies will focus on the prognostic value of SLICE in CRT candidates.

Systemic toll-like receptor and interleukin-18 pathway activation in patients with acute ST elevation myocardial infarction.

Acute myocardial infarction (AMI) is accompanied by increased expression of Toll like receptors (TLR)-2 and TLR4 on circulating monocytes. In animal models, blocking TLR2/4 signaling reduces inflammatory cell influx and infarct size. The clinical consequences of TLR activation during AMI in humans are unknown, including its role in long-term cardiac functional outcome Therefore, we analyzed gene expression in whole blood samples from 28 patients with an acute ST elevation myocardial infarction (STEMI), enrolled in the EXenatide trial for AMI patients (EXAMI), both at admission and after 4-month follow-up, by whole genome expression profiling and real-time PCR. Cardiac function was determined by cardiac magnetic resonance (CMR) imaging at baseline and after 4-month follow-up. TLR pathway activation was shown by increased expression of TLR4 and its downstream genes, including IL-18R1, IL-18R2, IL-8, MMP9, HIF1A, and NFKBIA. In contrast, expression of the classical TLR-induced genes, TNF, was reduced. Bioinformatics analysis and in vitro experiments explained this noncanonical TLR response by identification of a pivotal role for HIF-1α. The extent of TLR activation and IL-18R1/2 expression in circulating cells preceded massive troponin-T release and correlated with the CMR-measured ischemic area (R=0.48, p=0.01). In conclusion, we identified a novel HIF-1-dependent noncanonical TLR activation pathway in circulating leukocytes leading to enhanced IL-18R expression which correlated with the magnitude of the ischemic area. This knowledge may contribute to our mechanistic understanding of the involvement of the innate immune system during STEMI and may yield diagnostic and prognostic value for patients with myocardial infarction.

Cell therapy in reperfused acute myocardial infarction does not improve the recovery of perfusion in the infarcted myocardium: a cardiac MR imaging study.

PURPOSE: To investigate the effects of cell therapy on myocardial perfusion recovery after treatment of acute myocardial infarction (MI) with primary percutaneous coronary intervention (PCI). MATERIALS AND METHODS: In this HEBE trial substudy, which was approved by the institutional review board (trial registry number ISRCTN95796863), the authors assessed the effects of intracoronary infusion with bone marrow-derived mononuclear cells (BMMCs) or peripheral blood-derived mononuclear cells (PBMCs) on myocardial perfusion recovery by using cardiac magnetic resonance (MR) imaging after revascularization. In 152 patients with acute MI treated with PCI, cardiac MR imaging was performed after obtaining informed consent-before randomization to BMMC, PBMC, or standard therapy (control group)-and repeated at 4-month follow-up. Cardiac MR imaging consisted of cine, rest first-pass perfusion, and late gadolinium enhancement imaging. Perfusion was evaluated semiquantitatively with signal intensity-time curves by calculating the relative upslope (percentage signal intensity change). The relative upslope was calculated for the MI core, adjacent border zone, and remote myocardium. Perfusion differences among treatment groups or between baseline and follow-up were assessed with the Wilcoxon signed rank or Mann-Whitney U test. RESULTS: At baseline, myocardial perfusion differed between the MI core (median, 6.0%; interquartile range [IQR], 4.1%-8.0%), border zone (median, 8.4%; IQR, 6.4%-10.2%), and remote myocardium (median, 12.2%; IQR, 10.5%-15.9%) (P < .001 for all), with equal distribution among treatment groups. These interregional differences persisted at follow-up (P < .001 for all). No difference in perfusion recovery was found between the three treatment groups for any region. CONCLUSION: After revascularization of ST-elevation MI, cell therapy does not augment the recovery of resting perfusion in either the MI core or border zone.

In-vivo T1 cardiovascular magnetic resonance study of diffuse myocardial fibrosis in hypertrophic cardiomyopathy.

BACKGROUND: In hypertrophic cardiomyopathy (HCM), autopsy studies revealed both increased focal and diffuse deposition of collagen fibers. Late gadolinium enhancement imaging (LGE) detects focal fibrosis, but is unable to depict interstitial fibrosis. We hypothesized that with T1 mapping, which is employed to determine the myocardial extracellular volume fraction (ECV), can detect diffuse interstitial fibrosis in HCM patients. METHODS: T1 mapping with a modified Look-Locker Inversion Recovery (MOLLI) pulse sequence was used to calculate ECV in manifest HCM (n = 16) patients and in healthy controls (n = 14). ECV was determined in areas where focal fibrosis was excluded with LGE. RESULTS: The total group of HCM patients showed no significant changes in mean ECV values with respect to controls (0.26 ± 0.03 vs 0.26 ± 0.02, p = 0.83). Besides, ECV in LGE positive HCM patients was comparable with LGE negative HCM patients (0.27 ± 0.03 vs 0.25 ± 0.03, p = 0.12). CONCLUSIONS: This study showed that HCM patients have a similar ECV (e.g. interstitial fibrosis) in myocardium without LGE as healthy controls. Therefore, the additional clinical value of T1 mapping in HCM seems limited, but future larger studies are needed to establish the clinical and prognostic potential of this new technique within HCM.

Combined non-invasive functional and anatomical diagnostic work-up in clinical practice: the magnetic resonance and computed tomography in suspected coronary artery disease (MARCC) study.

AIMS: The combined use of cardiac computed tomography (CT) coronary angiography (CTCA) and myocardial perfusion imaging allows the non-invasive evaluation of coronary morphology and function. Cardiovascular magnetic resonance (CMR) imaging has several advantages: it can simultaneously assess myocardial perfusion, ventricular and valvular function, cardiomyopathy, and aortic disease and does not involve any additional ionizing radiation. We investigated the combined use of cardiac CT and CMR for the diagnostic evaluation of patients with suspected coronary artery disease (CAD) in clinical practice. METHODS AND RESULTS: A total of 192 patients with low or intermediate pre-test probability of CAD underwent CTCA and CMR. All patients with obstructive CAD on CTCA and/or myocardial ischaemia on CMR were referred for invasive coronary angiography (ICA). Fractional flow reserve was measured in case of intermediate lesions (30-70% diameter stenosis) on ICA. Additional cardiac and extra-cardiac findings by CTCA and CMR were registered. The combination of CTCA and CMR significantly improved specificity and overall accuracy (94 and 91%) for the detection of significant CAD compared with their use as a single technique (CTCA 39 and 57%, P < 0.0001; CMR 82 and 83%, P = 0.016). No events were recorded during follow-up (18 ± 6 months) in 104 patients who did not undergo ICA. Furthermore, the combined strategy provided an alternative diagnosis in 19 patients. CONCLUSION: The combined use of CTCA and CMR significantly improved specificity and overall diagnostic accuracy for the detection of significant CAD and allowed the detection of alternative (extra-)cardiac disease in patients without significant CAD.

Magnetic resonance imaging-defined areas of microvascular obstruction after acute myocardial infarction represent microvascular destruction and haemorrhage.

AIMS: Lack of gadolinium-contrast wash-in on first-pass perfusion imaging, early gadolinium-enhanced imaging, or late gadolinium-enhanced (LGE) cardiovascular magnetic resonance (CMR) imaging after revascularized ST-elevation myocardial infarction (STEMI) is commonly referred to as microvascular obstruction (MVO). Additionally, T2-weighted imaging allows for the visualization of infarct-related oedema and intramyocardial haemorrhage (IMH) within the infarction. However, the exact histopathological correlate of the contrast-devoid core and its relation to IMH is unknown. METHODS AND RESULTS: In eight Yorkshire swine, the circumflex coronary artery was occluded for 75 min by a balloon catheter. After 7 days, CMR with cine imaging, T2-weighted turbospinecho, and LGE was performed. Cardiovascular magnetic resonance images were compared with histological findings after phosphotungstic acid-haematoxylin and anti-CD31/haematoxylin staining. These findings were compared with CMR findings in 27 consecutive PCI-treated STEMI patients, using the same scanning protocol. In the porcine model, the infarct core contained extensive necrosis and erythrocyte extravasation, without intact vasculature and hence, no MVO. The surrounding-gadolinium-enhanced-area contained granulation tissue, leucocyte infiltration, and necrosis with morphological intact microvessels containing microthrombi, without erythrocyte extravasation. Areas with IMH (median size 1.92 [0.36-5.25] cm(3)) and MVO (median size 2.19 [0.40-4.58] cm(3)) showed close anatomic correlation [intraclass correlation coefficient (ICC) 0.85, r = 0.85, P = 0.03]. Of the 27 STEMI patients, 15 had IMH (median size 6.60 [2.49-9.79] cm(3)) and 16 had MVO (median size 4.31 [1.05-7.57] cm(3)). Again, IMH and MVO showed close anatomic correlation (ICC 0.87, r = 0.93, P < 0.001). CONCLUSION: The contrast-devoid core of revascularized STEMI contains extensive erythrocyte extravasation with microvascular damage. Attenuating the reperfusion-induced haemorrhage may be a novel target in future adjunctive STEMI treatment.

Cardiac involvement with amyloidosis: mechanisms of disease, diagnosis and management.

The amyloidoses represent a group of clinical disorders of diverse etiologies that have as a common pathophysiologic denominator the deposition of misfolded protein based amyloid fibrils in the interstitial space of various organs. They are uncommon diseases with protean clinical presentations. Cardiac involvement is the determining factor for a patient's prognosis. Clinicians have to maintain a high index of suspicion and actively search for signs and symptoms of cardiac involvement in patients with preexisting conditions known to be associated with the development of amyloidosis. Early diagnosis and accurate fibril typing are the first steps in managing the disease. Judicious use of various diagnostic modalities such as serum markers and imaging studies, and good communication among all the physicians involved in the care of these sick and frail patients, are keys to a better outcome.

Low to intermediate probability of coronary artery disease: comparison of coronary CT angiography with first-pass MR myocardial perfusion imaging.

PURPOSE: To compare coronary computed tomographic (CT) angiography with first-pass magnetic resonance (MR) myocardial perfusion imaging in patients with chest pain and low to intermediate probability of coronary artery disease (CAD). MATERIALS AND METHODS: Local ethics committee approval and patient written informed consent were obtained. Patients with chest pain and low to intermediate pretest probability of CAD underwent both coronary CT angiography and MR myocardial perfusion imaging. Coronary CT angiographic and MR myocardial perfusion images were analyzed qualitatively by blinded observers. Obstructive CAD was defined as more than 50% diameter stenosis at coronary CT angiography. Data were expressed with 95% confidence intervals (CIs) calculated from binomial expression. RESULTS: In 145 (94.2%) of 154 eligible patients, both coronary CT angiography and MR myocardial perfusion imaging were performed successfully. Mean age was 57 years +/- 10 (standard deviation), and 45.5% of patients were male. Mean interval between coronary CT angiography and MR myocardial perfusion imaging was 4.6 days +/- 3.0; median was 5.0 days. CT coronary angiography revealed obstructive CAD in 52 (35.9%) patients and 78 (17.9%) coronary arteries. At MR myocardial perfusion imaging, myocardial ischemia was demonstrated in 33 (22.8%) patients and 59 (13.6%) vessel territories. Of patients without CAD at coronary CT angiography, 90.5% (57 of 63; 95% CI: 82.6%, 95.0%) had normal myocardial perfusion at MR myocardial perfusion imaging. Of patients with nonobstructive CAD, 83.3% (25 of 30; 95% CI: 69.5%, 91.6%) had normal myocardial perfusion at MR myocardial perfusion imaging. Myocardial ischemia was detected at MR myocardial perfusion imaging in 42.3% (22 of 52; 95% CI: 29.5%, 56%) of patients with obstructive CAD at coronary CT angiography. CONCLUSION: MR myocardial perfusion imaging and coronary CT angiography have complementary roles in evaluation of patients who are suspected of having CAD. Coronary CT angiography can be used to reliably rule out CAD, but its capability to demonstrate hemodynamically significant CAD is limited. The combination of both techniques enables the clinician to evaluate morphology and functional relevance of CAD comprehensively and noninvasively.

Comparison of dual to single contrast bolus magnetic resonance myocardial perfusion imaging for detection of significant coronary artery disease.

PURPOSE: To investigate the incremental diagnostic value of dual-bolus over single-contrast-bolus first pass magnetic resonance myocardial perfusion imaging (MR-MPI) for detection of significant coronary artery disease (CAD). MATERIALS AND METHODS: Patients (n = 49) with suspected CAD underwent first pass adenosine stress and rest MR-MPI and invasive coronary angiography (CA). Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) was injected with a prebolus (1 mL) and a large bolus (0.1 mmol/kg). For the single-bolus technique, the arterial input function (AIF) was obtained from the large-contrast bolus. For the dual-bolus technique, the AIF was reconstructed from the prebolus. Absolute myocardial perfusion was calculated by Fermi-model constrained deconvolution. Receiver operating characteristic (ROC) analysis was used to investigate diagnostic accuracy of MR myocardial perfusion imaging for detection of significant CAD on CA at vessel-based analysis. RESULTS: The area under the curve (AUC) of the minimal stress perfusion value for the detection of significant CAD using the single-bolus and dual-bolus technique was 0.85 +/- 0.04 (95% confidence interval [CI], 0.77-0.93) and 0.77 +/- 0.05 (95% CI, 0.67-0.86), respectively. CONCLUSION: In this study the dual-bolus technique had no incremental diagnostic value over single-bolus technique for detection of significant CAD with the used contrast concentrations.

Improved correction of spatial inhomogeneities of surface coils in quantitative analysis of first-pass myocardial perfusion imaging.

PURPOSE: To test whether image normalization using either a separate 3D proton-density (PD)-weighted prescan, or 2D PD-weighted images prior to the perfusion series, improves correction of differences in spatial sensitivity induced by radiofrequency (RF) surface receiver coils. Originally, this correction was applied using the baseline signal in the myocardium before arrival of the contrast agent. This is of importance, as quantitative analysis of magnetic resonance (MR) myocardial perfusion using deconvolution with the arterial input assumes equal signal sensitivity over the heart. MATERIALS AND METHODS: First-pass myocardial perfusion measurements were obtained in 13 patients without known coronary artery disease. Absolute perfusion values were assessed for 18 myocardial segments without any normalization and using the three different normalization methods. RESULTS: Using 2D or 3D PD-weighted normalization, similar mean perfusion values were found, but with reduced spatial variance over the 18 segments. The relative dispersion of perfusion at rest was 23% and 35% for the 3D prescan normalization and the baseline normalization, respectively. With 2D and 3D PD-weighted prescan normalization the relative dispersion was closer to the expected physiological heterogeneity. CONCLUSION: PD-weighted prescan normalization proved to be a valuable addition to quantitative analysis of myocardial perfusion, and better than baseline-based normalization.

Risk stratification for ventricular arrhythmias in ischaemic cardiomyopathy: the value of non-invasive imaging.

The introduction of the implantable cardioverter defibrillator (ICD) has had a major impact on survival and treatment of patients with ischaemic cardiomyopathy. However, only a third of patients receive appropriate ICD discharges during the first 3 years of follow-up, hence creating opportunities for improvement in patient care as well as for health care costs containment. Therefore, refinement of ICD implantation criteria is needed. Evaluation of pathophysiological substrates related to electrical instability with imaging modalities such as nuclear imaging, cardiac magnetic resonance imaging, and echocardiography might yield important prognostic information. This review discusses the currently available literature regarding the value of these imaging modalities for prediction of ventricular arrhythmias in patients with ischaemic cardiomyopathy.

Negative delayed-enhancement magnetic resonance imaging of the heart suggests a diagnosis of neonatal transient myocardial ischaemia.

UNLABELLED: We report a term neonate presenting after birth with shock and cyanosis for which he was intubated. Echocardiography showed no contractions of the left ventricle. Systemic circulation was provided by the right ventricle via shunting through the arterial duct. Left ventricular dysfunction was confirmed by electrocardiography and increased troponin T levels. Hemodynamics quickly improved, and the child could be weaned of the ventilator without residual problems. We concluded that the patient suffered from transient myocardial ischaemia. At 3 weeks of life, we performed delayed-enhancement magnetic resonance imaging (DE-MRI) of the heart which did not show signs of permanent macroscopic damage of the myocardium. CONCLUSION: This is the first reported case report on the use of DE-MRI in a neonate with transient myocardial ischaemia. DE-MRI may provide information that helps to predict recovery in the acute stage of left ventricular dysfunction or at a later stage when absence of recovery of left ventricular function needs to be explained.

Assessment of microvascular obstruction and prediction of short-term remodeling after acute myocardial infarction: cardiac MR imaging study.

PURPOSE: To evaluate which cardiac magnetic resonance (MR) imaging technique for detection of microvascular obstruction (MVO) best predicts left ventricular (LV) remodeling after acute myocardial infarction (MI). MATERIALS AND METHODS: This study had local ethics committee approval; all patients gave written informed consent. Sixty-three patients with first acute MI, treated with primary stent placement and optimal medical therapy, underwent cine MR imaging at 4-7 days and at 4 months after MI. Presence of MVO was qualitatively evaluated at baseline by using three techniques: (a) a single-shot saturation-recovery gradient-echo first-pass perfusion sequence (early hypoenhancement), mean time, 1.09 minutes +/- 0.07 (standard deviation) after contrast material administration; (b) a three-dimensional segmented saturation-recovery gradient-echo sequence (intermediate hypoenhancement), mean time, 2.17 minutes +/- 0.26; and (c) a two-dimensional segmented inversion-recovery gradient-echo late gadolinium enhancement sequence (late hypoenhancement), mean time, 13.32 minutes +/- 1.26. Contrast-to-noise ratios (CNRs) were calculated from the signal-to-noise ratios of the infarcted myocardium and MVO areas. Univariable linear regression analysis was used to identify the predictive value of each MR imaging technique. RESULTS: Early hypoenhancement was detected in 44 (70%) of 63 patients; intermediate hypoenhancement, in 39 (62%); and late hypoenhancement, in 37 (59%). Late hypoenhancement was the strongest predictor of change in LV end-diastolic and end-systolic volumes over time (beta = 14.3, r = 0.40, P = .001 and beta = 11.3, r = 0.44, P < .001, respectively), whereas intermediate and late hypoenhancement had comparable predictive values of change in LV ejection fraction (beta = -3.1, r = -0.29, P = .02 and beta = -2.8, r = -0.27, P = .04, respectively). CNR corrected for spatial resolution was significantly superior for late enhancement compared with the other sequences (P < .001). CONCLUSION: By using cardiac MR imaging, late hypoenhancement is the best prognostic marker of LV remodeling, with highest CNR between the infarcted myocardium and MVO regions.

Quantification of late gadolinium enhanced CMR in viability assessment in chronic ischemic heart disease: a comparison to functional outcome.

BACKGROUND: Quantification of late gadolinium enhanced cardiovascular magnetic resonance (LGE CMR) by objective window setting increases reproducibility and facilitates multicenter comparison and cooperation. So far, quantification methods or models have only been validated to postmortem animal studies. This study was undertaken to evaluate quantification of LGE in relation to the clinical standard of viability, i.e. functional outcome after revascularization.Thirty-eight patients with chronic ischemic myocardial dysfunction underwent cine and LGE 1 month before and cine CMR 6 months after coronary revascularization. Enhancement was quantified by thresholding window setting at: 2-8 SD above mean signal intensity of a remote normal region, and according to the full width at half maximum method (FWHM). Dysfunctional segments were divided in 5 groups according to segmental extent of enhancement (SEE): SEE 1--no enhancement to SEE 5--76-100% with each quantification method. RESULTS: Quantification methods had a strong influence on SEE and total infarct size. Multilevel analysis showed that thresholding contrast images at 6 SD best predicted segmental functional outcome after revascularization, but the difference with other methods was small and non-significant. CONCLUSION: Simple thresholding techniques strongly influence global and segmental extent of LGE, but have relatively little influence on the accuracy to predict segmental functional improvement after revascularization.

Time course of functional recovery after revascularization of hibernating myocardium: a contrast-enhanced cardiovascular magnetic resonance study.

AIMS: We sought to evaluate the relation between long-term functional outcome after revascularization in patients with chronic ischaemic left ventricular (LV) dysfunction and baseline extent of myocardial fibrosis. METHODS AND RESULTS: Thirty-five patients underwent cine and delayed contrast-enhanced cardiovascular magnetic resonance (deCMR) for the quantitative assessment of regional and global LV functions and segmental extent of hyperenhancement (SEH). Function was assessed 1 month before and 3, 6, and 24 +/- 12 months after revascularization, and temporal changes were related to baseline extent of hyperenhancement. The likelihood of functional improvement was inversely related to the SEH during the entire follow-up: at the end of the study period, segments with 1-25, 26-50, 51-75, and 76-100% SEH were 2, 5, 11, and 86 times, respectively, less likely to have functional improvement than segments without hyperenhancement (multilevel analysis, P < 0.001). Although improvement continued over the whole study period in all SEH groups, the time course was significantly more delayed in segments with more extensive hyperenhancement at baseline (multilevel analysis, P < 0.001). CONCLUSION: In patients with chronic ischaemic LV dysfunction, improvement of dysfunctional but viable myocardium can be considerably delayed. Both the likelihood and the time course of long-term functional improvement are related to the baseline amount of scar, as visualized by deCMR.

Prognostic value of delayed gadolinium enhancement MRI in patients with ischemic cardiomyopathy.

BACKGROUND: Cardiovascular magnetic resonance imaging (CMR) with delayed contrast enhancement (DCE) using Gadolinium (Gd)-based magnetic contrastagents, is a technique which visualizes myocardial infarction (MI) as regions of bright signal (hyperenhancement) compared to normal myocardium. The prognostic value of DCE in patients with ischemic cardiomyopathy has not been fully characterized. METHODS: All patients with a history of coronary artery disease (CAD) who underwent DCE-CMR imaging between September 1999 and July 2004 were included. CMR-variables were: left ventricular ejection fraction (LVEF), wall motion, mitral regurgitation (MR) and DCE scores. The patient's clinical status was assessed using the New York Heart Association-classification (NYHA). RESULTS: One hundred and ninety-three patients (age 63+/-11, 42 women), including 160 with prior MI, were studied. The mean LVEF was 40+/-14%. Most patients (88%) were in NYHA-class I or II, and 8% had moderate or severe MR. Thirteen patients died during follow-up. Patients who died had a lower baseline LVEF and more significant MR compared to survivors (P=0.04). A higher DCE score was associated with more significant MR (P=0.01). No significant association was demonstrated between NYHA-class and DCE (P=0.34) or between DCE score andmortality (P=0. 8). CONCLUSION: The study reinforces the important prognostic value of resting LVEF and MR severity in patients with CAD and is the first to demonstrate an association between the degree of DCE and MR severity in these patients. Further investigations including a larger number of patients are needed to fully assess the prognostic value of DCE-CMR in ischemic cardiomyopathy.

Semi-quantitative assessment of right ventricular function in comparison to a 3D volumetric approach: a cardiovascular magnetic resonance study.

Right ventricular (RV) volume measurements with cardiovascular magnetic resonance (CMR) is considered the gold standard, but acquisition and analysis remain time-consuming. The aim of our study was therefore to investigate the accuracy and performance of a semi-quantitative assessment of RV function in CMR, compared to the standard quantitative approach. Seventy-five subjects with pulmonary hypertension (15), anterior myocardial infarction (15), inferior myocardial infarction (15), Brugada syndrome (15) and normal subjects (15) underwent cine CMR. RV end-systolic and end-diastolic volumes were determined to calculate RV ejection fraction (EF). Four-chamber cine images were used to measure tricuspid annular plane systolic excursion (TAPSE). RV fractional shortening (RVFS) was calculated by dividing TAPSE by the RV end-diastolic length. RV EF correlated significantly with TAPSE (r = 0.62, p < 0.01) and RVFS (r = 0.67, p < 0.01). Sensitivity to predict RV dysfunction was comparable between TAPSE and RVFS, with higher specificity for RVFS, but comparable areas under the ROC curve. Intra- and inter-observer variability of RV EF was better than TAPSE (3%/4% versus 7%/15%, respectively). For routine screening in clinical practice, TAPSE and RVFS seem reliable and easy methods to identify patients with RV dysfunction. The 3D volumetric approach is preferred to assess RV function for research purposes or to evaluate treatment response.

Additional diagnostic value of CMR to the European Society of Cardiology (ESC) position statement criteria in a large clinical population of patients with suspected myocarditis.

Aims: To determine the diagnostic yield of tissue characterization by cardiovascular magnetic resonance (CMR) in a large clinical population of patients with suspected acute myocarditis (AM) and to establish its diagnostic value within the 2013 European Society of Cardiology position statement criteria (ESC-PSC) for clinically suspected myocarditis. Methods and results: In this retrospective study, CMR examinations of 303 hospitalized patients referred for work-up of suspected AM in two tertiary referral centres were analysed. CMR was performed at median 7 days (interquartile range 4-20 days) after clinical presentation and included cine imaging, T2-weighted imaging, and late gadolinium enhancement. CMR images were evaluated to assign each patient to a diagnosis. By using non-CMR criteria only, the 2013 ESC-PSC were positive for suspected myocarditis in 151 patients and negative in 30. In the remaining 122 patients, there was insufficient information available for ESC-PSC assessment, mostly due to lack of coronary angiography (CAG) before the CMR examination (n = 116, 95%). There were no in-hospital deaths. CMR provided a diagnosis in 158 patients (52%), including myocarditis in 104 (34%), myocardial infarction in 44 (15%), and other pathology in 10 patients (3%). Non-urgent CAG (>24 h after presentation) was performed before the CMR examination in 85 patients, of which 20 (24%) were done in patients with subsequently confirmed AM, which could potentially have been avoided if CMR was performed first. ESC-PSC was correct in diagnosing AM before the CMR in 50 of the 151 patients (33%) and was correct in ruling out AM in all the 30 patients (100%). However, ESC-PSC provided an incorrect diagnosis of AM in 27 of the 151 patients (18%), which was corrected by CMR through the identification of new cardiac disease that could explain the clinical syndrome. Patients with insufficient ESC-PSC information had a relatively low pre-test probability of coronary artery disease. In this group, CMR confirmed the diagnosis of AM in a relatively high percentage (44%) but still revealed myocardial infarction in 8% of them. Conclusion: Tissue characterization by CMR provided a good diagnostic yield in this large clinical population of patients with suspected AM. CMR provided incremental diagnostic value to the ESC-PSC by ruling out the diagnosis of AM on one hand and by potentially sparing AM patients from CAG on the other.