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Background CMR has become an increasingly valuable tool in the diagnosis and risk stratification of patients with nonischaemic dilated cardiomyopathy (DCM) due to its assessment of left ventricular systolic function and tissue characterization ability and may have a role in early identification of cardiomyopathy. Some of the changes associated with early DCM (left ventricular dilatation and mild reduction in LV ejection fraction) can also occur in patients with a history of significant aerobic exercise, known as “athlete’s heart”. Using standard echocardiographic and CMR parameters it may be difficult to differentiate between DCM and normal physiological athletic adaptation, which may have significant implications for the patient. We hypothesized that use of CMR tagging and T1 and T2 mapping might be useful to differentiate between patients with left ventricular dilatation due to DCM and athlete’s heart.

Background Left ventricular ejection fraction (LVEF) is powerful predictor of mortality and is used to guide treatment decisions. It is however subject to limitations, particularly when measured using echocardiography, as is most commonly done. Additionally, many major cardiovascular events occur in patients typically adjudged to be at lower risk using echocardiography (LVEF >35%). Assessment of myocardial deformation (strain) using tagging has the potential to overcome some of the limitations of LVEF. The value of global circumferential strain (GCS) measured by CMR tagging in patients with suspected cardiac disease has not been fully explored despite it being considered as the non-invasive gold standard method of assessment of LV deformation. We aimed to assess the incremental prognostic value of GCS measured using tagging for the prediction of major adverse cardiovascular events in addition to baseline clinical characteristics, LVEF and late gadolinium enhancement (LGE) in an unselected cohort of patients.

Background In patients with myocardial infarction (MI), an important factor in determining the long-term prognosis is the degree of regional contractile dysfunction. DENSE (Displacement ENcoding with Stimulated Echoes) is a technique which allows quantification of myocardial strain[1], and which has been shown to be more sensitive to the presence of late gadolinium enhancement (LGE) than wall thickening measured from cine images[2]. The aim of this study was to further investigate the performance of DENSE for the diagnosis and assessment of myocardial infarction. Methods 50 male patients (age 56 ± 10 years) within 7 days of MI and 30 healthy male controls (age 45 ± 18 years) underwent CMR on a 1.5T Siemens Avanto. The protocol included DENSE and LGE (patients only) obtained from a single mid-ventricular short-axis slice, which was divided into 6 segments for analysis. The percentage of each segment which contained LGE was calculated using a threshold of mean+5SD of remote myocardium intensity. DENSE images were analysed to obtain a value for peak circumferential strain (Ecc). The following analyses were performed: (i) intra- and inter-operator and inter-scan repeatability, (ii) sensitivity and specificity for the detection of LGE, using a reference range established from control data, and ROC analysis and (iii) the ability to distinguish between non-infarcted, 50% infarction, and between remote, adjacent and infarcted segments. Results along with the percentages of segments correctly identified when grouped according to extent of LGE. The reference range was calculated to be (-11.8, -27.0). Inter-operator repeatability was assessed using Levene’s test (variance) and a paired t-test (mean), and no statistically significant differences were found. A paired t-test found no statistically significant difference for inter-scan repeatability. The results of (iii) are illustrated in Figure 1. Comparisons between categories were performed using a one-way ANOVA with Tukey’s post-hoc test. Conclusions DENSE can be successfully applied in a clinical setting, and provides repeatable results. The sensitivity and specificity of the technique for detecting the presence of LGE are good, and the number of segments with LGE correctly identified increases as the extent of LGE increases. Peak

Background:\ud Myocardial transverse relaxation time (T2, ms) is a fundamental magnetic property of tissue that is related to water content and mobility. The pathophysiological and prognostic importance of native myocardial T2 in acute ST-elevation myocardial infarction (STEMI) patients is unknown. We aimed to assess the clinical significance of native T2 within the infarct core using cardiac magnetic resonance (CMR) imaging.\ud \ud Methods:\ud We performed a prospective single center cohort study in reperfused STEMI patients who underwent CMR 2 days and 6 months post-MI. T2-weighted CMR (investigational prototype T2-prepared TrueFisp sequence) was measured in myocardial regions-of-interest. The infarct territory and microvascular obstruction were depicted with late gadolinium enhancement CMR. All-cause death or heart failure hospitalization was a pre-specified outcome that was assessed during follow-up.\ud \ud Results:\ud 324 STEMI patients (mean±SD age 59±12 years, 237 males, 121 with anterior STEMI) gave informed consent and had CMR (14 July 2011 - 22 November 2012). All 324 had follow-up assessments (median duration 860 days). Infarct size was 18 ±14% of LV mass. One hundred and sixty four (51%) patients had late microvascular obstruction whereas 197 (61%) patients had an infarct core revealed by native T2. Native T2 within the infarct core (53.9±4.8) was higher than in the remote zone (49.7±2.1 ms; p

Background:\ud The pathophysiology and prognostic significance of remote myocardium in the natural history of STEMI is uncertain. Cardiac magnetic resonance (CMR) provides a non-invasive assessment of myocardial pathology that is spatially and temporally coordinated. Native T1 quantified by CMR (T1 relaxation time, milliseconds) is a fundamental tissue property determined by water content and cellularity. We aimed to investigate the clinical significance of remote myocardium in survivors of acute ST-elevation myocardial infarction (STEMI) using native T1 mapping.\ud \ud Methods:\ud We performed a prospective single center cohort study in reperfused STEMI patients who underwent CMR 2 days and 6 months post-MI and long term follow-up (18 months minimum). Native T1 CMR (MOLLI investigational prototype sequence: 3 (3) 3 (3) 5) was measured in regions-of-interest in remote and injured myocardium. Infarction was depicted on late gadolinium contrast enhancement imaging. Adverse remodeling was defined as an increase in left ventricular end-diastolic volume ≥ 20% at 6 months. Major adverse cardiac events (MACE) were defined as cardiac death or hospitalization for non-fatal MI or heart failure. Results are mean±SD unless specified.\ud \ud Results:\ud 300 STEMI patients (mean age 59 years, 74% male) gave informed consent (14 July 2011 - 21 November 2012). Of these, 288 STEMI patients had evaluable native T1 CMR and follow-up data (median duration 845 days). Infarct size was 18±14% of left ventricular mass. Two days post-STEMI, native T1 in remote myocardium was lower than native T1 in the infarct zone (961±25 ms vs. 1097±52 ms; p

Background:\ud In the Preventive Angioplasty in Myocardial Infarction trial (PRAMI; ISRCTN73028481), immediate multivessel PCI (MV-PCI) of non-IRA (infarct related artery) lesions in patients with acute ST elevation myocardial infarction (STEMI) and multivessel coronary disease (MVD) improved long term prognosis. We assessed infarct distribution and size in a pre-specified cardiac magnetic resonance (CMR) sub-study.\ud \ud Methods:\ud In this single centre prospective sub-study, PRAMI participants were invited to undergo 1.5 Tesla CMR 1 week and 1 year after primary PCI. The CMR scans were analysed using semi-automated software by a clinician blinded to treatment group assignment and clinical outcomes. The presence and extent of infarction were assessed quantitatively with late gadolinium enhancement (LGE) imaging (Gadovist, 0.1 mmol/kg). The infarct was delineated as an area of myocardial enhancement (cm2) using a signal intensity threshold of >5SDs above a remote region, and expressed as a % of total LV mass. The incidence of new LGE in non-infarct related artery territories at baseline and 1 year were assessed. Data were analysed by an independent statistician.\ud \ud Results:\ud Of 465 randomised trial participants in 6 UK hospitals, 138 (30%) were enrolled in Glasgow. Of these 80 patients underwent CMR 1 week post primary PCI of whom 41 (51%) were in the multi-vessel PCI group and 39 (49%) were in the IRA-only group. At 1 year, 69 (86%) patients had a follow up CMR scan. Infarct size and distribution are described in Table 1.

Background Myocardial infarction (MI) causes contractile dysfunction in the affected tissue, which can be assessed by using DENSE (Displacement ENcoding with Stimulated Echoes) to quantify myocardial strain[1,2]. The aim of this study was to investigate changes in strain revealed by DENSE between the occurrence of MI and a 6 month follow-up, and the relationships with other clinical measures. Methods 50 male patients (age 56 ± 10 years) underwent CMR on a 1.5T Siemens Avanto within 7 days of MI, and 47 returned for a follow-up scan after 6 months. The protocol included cine, DENSE (2D) and late gadolinium enhancement (LGE) imaging. Cine images were used to assess cardiac function by calculating LV ejection fraction (LVEF) and end-systolic volume (LVESV). DENSE and LGE were compared using a single mid-ventricular short-axis slice, which was analysed both as a whole slice and after division into 6 AHA segments. The percentage of each segment which contained LGE was calculated using a threshold of mean +5SD of remote myocardium intensity. DENSE images were analysed to obtain a value for peak circumferential strain (Ecc). Segments in the baseline scans were grouped according to the extent of LGE (non-infarcted, 50% infarcted), and the change in peak Ecc between baseline and follow-up was evaluated using a oneway ANOVA with Tukey’s post-hoc test. Individual patients were compared directly, and the correlations between change in strain and (i) change in LGE (segments) and (ii) change in cardiac function (slices) were assessed. Results Diagnostic images were obtained for 50 patients at baseline, and for 43 patients at follow-up. The results of the group comparisons and the individual patient comparisons are illustrated in Figure 1 and Figure 2 respectively. Conclusions Strain recovery was disclosed by DENSE in infarcted tissue at 6 months post-MI. An increase in peak Ecc at follow-up is associated with a reduction in LGE, and improvement in

Background T1 and T2 cardiac magnetic resonance (CMR) mapping methods have shown promise for infarct characterisation in patients with acute ST-elevation myocardial infarction (STEMI). Non-ST elevation MI is typically a sub-acute problem with infarct characteristics that are less readily defined. We prospectively studied the diagnostic accuracy of two novel (T1, T2 mapping) and one established (T2 STIR) CMR methods for imaging the ischaemic area-at-risk (AAR) in patients with a recent NSTEMI. Methods NSTEMI patients underwent contrast-enhanced CMR at 3.0 Tesla (T) after percutaneous coronary intervention. The presence/extent of infarction was assessed with late gadolinium enhancement imaging (Gadovist, 0.1 mmol/kg). The infarct-related territory (IRA) was identified independently using a combination of angiographic, ECG and clinical findings. AAR was assessed with T1, T2 and T2 STIR methods by 2 observers who were blind to all of the clinical data. Comparisons were made between CMR and clinical findings. Results Seventy-three NSTEMI patients (mean age 57 ± 10 yrs, 78% male) underwent 3.0 T MRI. The mean infarct size was 5.5 ± 7.2% of left ventricular (LV) volume. The AAR T1 and T2 times were 1323 ± 68 ms and 57 ± 5 ms, respectively. The extent of AAR (% of LV volume) estimated with T1 (15.8 ± 10.6%) and T2 maps (16.0 ± 11.8%) was similar (p = 0.838), and moderately well correlated (r = 0.82, p Mean AAR estimated with T2 STIR (7.8 ± 11.6%) was lower than that estimated with T1 (p The IRA was correctly identified in 52 patients (71%) when with T1 CMR, 56 (77%) with T2 CMR, and 32 (44%) with T2 STIR CMR. The diagnostic accuracies of T1 and T2 CMR for identification of the IRA were similar (p = 0.125) whereas T1 CMR and T2 CMR had higher diagnostic accuracy vs. T2 STIR (both p Conclusion T1 and T2 maps have higher diagnostic accuracy than T2 STIR maps, implying superior clinical utility with T1 and T2 CMR for infarct characterisation in NSTEMI patients.

Background In the Randomised Trial of Preventive Angioplasty in Myocardial Infarction (PRAMI; ISRCTN73028481), compared with infarct-related artery (IRA)-only PCI, additional immediate multivessel PCI (MV-PCI) of non-IRA lesions in patients with acute ST elevation myocardial infarction (STEMI) and multivessel coronary disease (MVD) improved long term prognosis. We studied left ventricular (LV) outcomes in a pre-specified cardiac magnetic resonance (CMR) sub-study. Methods In a single centre prospective sub-study, PRAMI participants were invited to undergo CMR at 1.5 Tesla 1 week and 1 year after primary PCI. LV volumes and function were analysed using semi-automated software by a clinician blinded to treatment group assignment and clinical outcomes. The statistical analyses were performed by an independent statistician. Results Of 465 randomised trial participants in 6 UK hospitals, 138 (30%) were enrolled in Glasgow. Eighty patients (17%) (mean age 60 years, 76% male) underwent CMR initially (n = 41 (51%) in the multi-vessel PCI group; n = 39 (49%) in the IRA-only group). 69 (86%) of these patients had a follow up CMR scan at 1 year (n = 7 lost to follow-up, n = 4 deceased). Mean (and SD) LVEF and volumes at 1 week post-MI and their change at 1 year from baseline were similar (Table 1). Conclusion The CMR sub-study participants represented the majority of all randomised participants in our hospital, which included one third of the PRAMI trial population. Random treatment group assignment in this CMR study was evenly balanced. LV function and volumes were similar at 1 week and 1 year post-intervention in survivors. The CMR sub-study suggests that the benefit of the preventive PCI strategy in PRAMI may not be mediated by any effects on LV function and remodelling. Funding Golden Jubilee National Hospital; PRAMI was funded by Barts and the London Charity.