CMR quantitation of change in mitral regurgitation following transcatheter aortic valve replacement (TAVR): impact on left ventricular reverse remodeling and outcome.

Current echocardiographic data reporting the impact of concomitant mitral regurgitation (MR) on outcome in patients who undergo transcatheter aortic valve replacement (TAVR) are conflicting. Using cardiovascular magnetic resonance (CMR) imaging, this study aimed to assess the impact of MR severity on cardiac reverse remodeling and patient outcome. 85 patients undergoing TAVR with CMR pre- and 6 m post-TAVR were evaluated. The CMR protocol included cines for left (LV) and right ventricular (RV) volumes, flow assessment, and myocardial scar assessment by late gadolinium enhancement (LGE). Patients were dichotomised according to CMR severity of MR fraction at baseline ('non-significant' vs 'significant') and followed up for a median duration of 3 years. Forty-two (49%) patients had 'significant MR' at baseline; they had similar LV and RV size and function compared to the 'non-significant MR' group but had greater LV mass at baseline. In those with significant MR at baseline, 77% (n = 32) had a reduction in MR post-TAVR, moving them into the 'non-significant' category at 6-months, with an overall reduction in MR fraction from 34 to 17% (p < 0.001). Improvement in MR was not associated with more favourable cardiac reverse remodeling when compared with the 'non-improvers'. Significant MR at baseline was not associated with increased mortality at follow-up. Significant MR is common in patients undergoing TAVR and improves in the majority post-procedure. Improvement in MR was not associated with more favourable LV reverse remodeling and baseline MR severity was not associated with mortality

Left ventricular thrombus formation in myocardial infarction is associated with altered left ventricular blood flow energetics.

Aims: The main aim of this study was to characterize changes in the left ventricular (LV) blood flow kinetic energy (KE) using four-dimensional (4D) flow cardiovascular magnetic resonance imaging (CMR) in patients with myocardial infarction (MI) with/without LV thrombus (LVT). Methods and results: This is a prospective cohort study of 108 subjects [controls = 40, MI patients without LVT (LVT- = 36), and MI patients with LVT (LVT+ = 32)]. All underwent CMR including whole-heart 4D flow. LV blood flow KE wall calculated using the formula: KE=12 ρblood . Vvoxel . v2, where ρ = density, V = volume, v = velocity, and was indexed to LV end-diastolic volume. Patient with MI had significantly lower LV KE components than controls (P  0.05). The relative drop in A-wave KE from mid-ventricle to apex and the proportion of in-plane KE were higher in patients with LVT+ compared with LVT- (87 ± 9% vs. 78 ± 14%, P = 0.02; 40 ± 5% vs. 36 ± 7%, P = 0.04, respectively). The time difference of peak E-wave KE demonstrated a significant rise between the two groups (LVT-: 38 ± 38 ms vs. LVT+: 62 ± 56 ms, P = 0.04). In logistic-regression, the relative drop in A-wave KE (beta = 11.5, P = 0.002) demonstrated the strongest association with LVT. Conclusion: Patients with MI have reduced global LV flow KE. Additionally, MI patients with LVT have significantly reduced and delayed wash-in of the LV. The relative drop of distal intra-ventricular A-wave KE, which represents the distal late-diastolic wash-in of the LV, is most strongly associated with the presence of LVT

Fully automated, inline quantification of myocardial blood flow with cardiovascular magnetic resonance: repeatability of measurements in healthy subjects

Background: Non-invasive assessment of myocardial ischaemia is a cornerstone of the diagnosis of coronary artery disease. Measurement of myocardial blood flow (MBF) using positron emission tomography (PET) is the current reference standard for non-invasive quantification of myocardial ischaemia. Dynamic myocardial perfusion cardiovascular magnetic resonance (CMR) offers an alternative to PET and a recently developed method with automated inline perfusion mapping has shown good correlation of MBF values between CMR and PET. This study assessed the repeatability of myocardial perfusion mapping by CMR in healthy subjects. Methods: Forty-two healthy subjects were recruited and underwent adenosine stress and rest perfusion CMR on two visits. Scans were repeated with a minimum interval of 7 days. Intrastudy rest and stress MBF repeatability were assessed with a 15-min interval between acquisitions. Interstudy rest and stress MBF and myocardial perfusion reserve (MPR) were measured for global myocardium and regionally for coronary territories and slices. Results: There was no significant difference in intrastudy repeated global rest MBF (0.65 ± 0.13 ml/g/min vs 0.62 ± 0.12 ml/g/min, p = 0.24, repeatability coefficient (RC) =24%) or stress (2.89 ± 0.56 ml/g/min vs 2.83 ± 0.64 ml/g/min, p = 0.41, RC = 29%) MBF. No significant difference was seen in interstudy repeatability for global rest MBF (0.64 ± 0.13 ml/g/min vs 0.64 ± 0.15 ml/g/min, p = 0.80, RC = 32%), stress MBF (2.71 ± 0.61 ml/g/min vs 2.55 ± 0.57 ml/g/min, p = 0.12, RC = 33%) or MPR (4.24 ± 0.69 vs 3.73 ± 0.76, p = 0.25, RC = 36%). Regional repeatability was good for stress (RC = 30–37%) and rest MBF (RC = 32–36%) but poorer for MPR (RC = 35–43%). Within subject coefficient of variation was 8% for rest and 11% for stress within the same study, and 11% for rest and 12% for stress between studies. Conclusions: Fully automated, inline, myocardial perfusion mapping by CMR shows good repeatability that is similar to the published PET literature. Both rest and stress MBF show better repeatability than MPR, particularly in regional analysis

P323 Early measurement of left ventricular global longitudinal strain and mechanical dispersion predict left ventricular remodeling at 5 year follow up after STEMI: pilot study

Abstract Funding Acknowledgements This work was supported by CREDO Project - ID: 49182, financed through the SOP IEC -A2-0.2.2.1-2013-1 cofinanced by the ERDF. Background Left ventricule (LV) function plays an important role in the pathophysiology of decompensation after acute ST elevation myocardial infarction (STEMI). LV remodeling (LVR) after STEMI is associated with development of heart failure, predicting poor clinical outcome therefore its identification is of clinical importance to set up preventive strategies. Prediction of the left ventricular remodeling (LVR) after STEMI in patients treated by primary PCI is challenging. Purpose Finding an echocardiographic parameter that can predict left ventricular remodeling in time after STEMI. Materials and methods In this prospective study we included 30 consecutive patients, median age 60 (37-79), 76% male, with STEMI treated by primary PCI. We performed conventional 2D transthoracic echocardiography for all included patients. In addition to conventional parameters we measured LV global longitudinal strain (GLS) and LV mechanical dispersion using 2D speckle tracking imaging technique. For morphological and functional analysis of LV we used 3D echocardiography (volumes, LVEF) considering its superiority in assessment of LV. All measurements were performed at baseline (up to 7 days after STEMI) and at 5 year follow up. LVR was defined as an increase of over 15% of the LV end diastolic volume (LVEDV) in time, at 5 years after the STEMI. Results We obtained significant differences in time (up to 7 days after STEMI vs at 5 years) between 3D LVEF (46,48 vs 51,68, p = 0.002), LVEDV (97,12 vs 107,76, p = 0.000), 2D global strain (-11.76 vs - 14,1, p = 0.00), and mechanical dispersion (65,06 vs 57,66, p = 0.00) in all patients. LV remodeling at 5 years (15% increase in LVEDV) was observed in 36,6% of the included patients. At 5 years follow up, LVEDV mean value in the remodeling group was 130 ml and in the no remodeling group 90,21 ml (p = 0.002), 3D LVEF was 48,18 vs 54,42 (p = 0.05), global strain was - 12,33 vs -15,35 (p = 0.02) and LV mechanical dispersion 66,27 vs 55,55 (p = 0.05). Therefore patients with LV remodeling in time had lower LVEF, lower global strain and higher LV mechanical dispersion at baseline. Using ROC analysis we identified two cut off values, one of -11.55 for global LV strain measured at baseline (Sb 81.8%, Sp 77%, AUC 0.776, CI 95%, p = 0.022) and the other one of 63.7 for LV mechanical dispersion at admission (Sb 72,7%, Sp 62%, AUC 0.734, p 0.05) to discriminate between patients with or without LV adverse remodeling at 5 years after STEMI. We also found, using regression analysis, that GLS and LV mechanical dispersion are able to predict LV remodeling in time. Conclusion Global longitudinal strain and left ventricular mechanical dispersion measured in the acute phase can predict which patient is likely to undergo LV remodeling at 5 years after STEMI. GLS and LV dispersion could be used as predictors for future LV adverse remodeling after STEMI. Larger scale studies are needed to validate these findings. </jats:sec

P1724 Bidimensional echocardiographical radial strain abnormalities mandate differential diagnosis between athlete heart syndrome and incipient genetic cardiomyopathy

Abstract Background Left ventricular dilation and mild systolic dysfunction at rest in young endurance athletes may mandate differential diagnosis between adaptive physiology and various forms of incipient non-ischemic dilated cardiomyopathies, especially if family history is positive. Multimodal imaging (i.e. bidimensional echocardiography (TTE), speckle tracking echography (STE) and cardiac magnetic resonance (CMR)) can accurately diagnose "true" underlying heart disease. Purpose We sought to outline the efficacy of multimodality imaging in dilated left ventricular phenotypes with mild systolic dysfunction of athletes. Methods We present the case of a 45 year old Caucasian male, rock climbing athlete (14 hours of training per week), with no prior personal medical history, who was admitted for fast palpitations leading to syncope immediately after a training session. Family history revealed maternal non-ischemic cardiomyopathy with complete atrioventricular (AV block requiring permanent pacing at a similar age. Stable, clinically asymptomatic, nodal complete AV block ∼ 40 bpm was diagnosed by ECG. TTE revealed a dilated LV (61 mm left ventricular end-diastolic diameter (LVIDd)) with no hypertrophy, with decreased diffuse contractility (LVEF ∼ 43%). Exercise echocardiography showed no improvement in LVEF, despite transition from complete AV block to first AV grade block. Moreover, moderate mitral regurgitation by posterior mitral leaflet (PML) prolapse was discovered. STE demonstrated normal global longitudinal strain (GLS), but decreased interventricular septum (IVS) radial strain (RS) (figure A). Late gadolinium enhancement was evident along the interventricular septum and the right ventricular insertion points in CMR (figure B), with no edema. Results The association of LV dilation (with multiple apparent causes – endurance training, genetic substrate, PML prolapse) with mild systolic dysfunction that persisted during echocardiographic exercise testing and a reduced IVS RS (with physiological GLS) was observed. Subsequently, mid-myocardial septal scarring in CMR was consistent with a diagnosis of "true" dilated cardiomyopathy. A cardiac resynchronization defibrillator device was implanted and genetic testing is in progress (lamin disease suspicion). Conclusions Athlete’s heart syndrome phenotypes may overlap with forms of genetic dilated cardiomyopathy. 1. The diagnostic suspicion of structural heart disease derived from echocardiography (radial strain &amp; exercise echocardiography abnormalities), with subsequent confirmation by late gadolinium enhancement myocardial fibrosis. 2. The prospective sudden cardiac death risk requires careful assessment. The presence of clinical arrhythmic syncope, septal CMR fibrosis and specific genetic mutation lead to the decision of ICD (internal cardioverter defibrillator) implantation. Abstract P1724 Figure. A - 2D Radial strain B - LGE CMR</jats:p

P1385 Mechanical dispersion of the right atrium in dilated cardiomyopathy: does the etiology matter?

Abstract Funding Acknowledgements This work was supported by CREDO Project - ID: 49182, financed through the SOP IEC -A2-0.2.2.1-2013-1 cofinanced by the ERDF Background Mechanical dispersion assessed by myocardial strain reflects a susceptibility for arrhythmia development. While the contractile heterogeneity of both ventricles has been assessed in different clinical settings, the incidence and significance of right atrial (RA) dyssynchrony in dilated cardiomyopathy (DCM) are unknown. Methods 50 consecutive patients with DCM were divided in 2 groups according to the etiology: group I had 26 patients with ischemic DCM (68 ± 10 years, 23 men), group N had 24 patients with non-ischemic DCM (52 ± 12 years, 18 men). We assessed the RA strain by 2D speckle-tracking analysis, and we calculated RA mechanical dispersion as the standard deviation of the time-to-peak contraction strain in 6 RA segments. 20 healthy individuals served as controls. Data were compared between groups with one-way analysis of variance and using a post-hoc Bonferroni correction. Results The RA strain was reduced in DCM patients, both in group I and in group N. All three components of the RA strain were most reduced in group I (p &amp;lt; 0.001 for reservoir and conduit strain, p = 0.001 for contraction strain) (Table). The RA mechanical dispersion was highest in group I (56.8 ± 21.6 ms), followed by group N (39.9 ± 15.3 ms) and controls (23.8 ± 7.7 ms)(p &amp;lt; 0.001). Patients with DCM and documented supraventricular arrhythmias (either atrial fibrillation, atrial flutter or premature atrial contractions) had higher RA mechanical dispersion (57.5 ± 19.7 ms) than DCM patients with no documented atrial rhythm disturbances (44.9 ± 19.9 ms, p = 0.04). Conclusion Mechanical dispersion of the RA is pronounced in patients with DCM and it is higher in patients with documented supraventricular arrhythmias. Patients with ischemic DCM have a more pronounced mechanical dispersion of the RA than patients with non-ischemic DCM, reflecting a more heterogenous RA contraction in ischemic heart disease when compared to other forms of DCM. The prognostic significance of RA dyssynchrony in a disease primarily involving the left heart warrants further studies. Group I Group N Controls P value Reservoir RA strain (%) 12.9 ± 7.4§ 17.6 ± 12.9§ 30.1 ± 9.9 &amp;lt;0.001 Conduit RA strain (%) -6 ± 5.5§ -8 ± 8.9§ -15.2 ± 6.4 &amp;lt;0.001 Contraction RA strain (%) 6.9 ± 6§ 9.6 ± 8.1 14.9 ± 6.1 0.001 RA mechanical dispersion (ms) 56.8 ± 21.6§ 39.±15.3§* 23.8 ± 7.7 &amp;lt;0.001 § significant difference with controls; * significant difference with group I </jats:sec