Global Left Ventricular Research Articles

Abstract 17328: A Case of Reversible Severe Systolic Cardiomyopathy; Thinking Outside the Box

Introduction: Non-ischemic systolic cardiomyopathy is associated with significant morbidity and mortality. Prompt evaluation and timely removal of the potential insult may lead to reverse remodeling and recovery of the left ventricular (LV) systolic function. Case: A 39-year-old female with BMI 40 presented with dyspnea and bilateral lower extremity edema. Vital signs significant for mild tachycardia and hypertension. ECG showed sinus tachycardia. Physical exam revealed bibasilar crackles and 3+ pitting edema of the lower extremities. Laboratory significant for NTpro BNP 563 pg/dL and TSH <0.005 IU/mL with a free T4 of 2.73 ng/dL. Chest x-ray showed pulmonary vascular congestion. Echocardiogram showed severely reduced LV systolic function with ejection fraction (EF) of 27%, global LV hypokinesis and diastolic LV diameter of 6.85 cm. No significant atrial or ventricular arrhythmias noted on Telemetry. A CT angiography of the coronary arteries showed no evidence of calcification or obstructive coronary disease. Additional labs revealed severely elevated TSH receptor antibody and thyroid stimulating immunoglobulin. Diffuse thyroid enlargement noted on ultrasound. Patient was diagnosed with Grave’s disease (GD) with Burch-Wartofsky score of 30 indicating an impending thyroid storm. She was treated with Metoprolol and Methimazole. She underwent intravenous diuresis and was started on guideline-directed medical therapy for systolic cardiomyopathy. In follow-up after 6 months, her TSH had normalized. On repeat imaging, her LVEF improved to > 50% with diastolic LV diameter of 5.6 cm. Discussion: This patient was diagnosed with non-ischemic dilated systolic cardiomyopathy due to severe hyperthyroidism from GD. Thyrotoxicosis-induced systolic cardiomyopathy occurs in about 1% of patients with GD and is associated with increased morbidity and mortality. Excess thyroid hormones in thyrotoxicosis can affect multiple regulatory and structural genes of cardiac myocytes resulting in abnormal intracellular calcium regulation and impaired LV systolic and diastolic function. Our experience is consistent with literature demonstrating the importance of timely diagnosis and treatment of this reversible cause of systolic cardiomyopathy.

Assessment of subclinical left ventricular myocardial systolic dysfunction in type 2 diabetes mellitus patients with or without hypertension by global and segmental myocardial work

ObjectiveThe research was aimed to evaluate the subclinical left ventricular (LV) myocardial systolic dysfunction in T2DM patients with or without hypertension (HT) by global and segmental myocardial work (MW).MethodsA total of 120 T2DM patients (including 60 T2DM patients with HT) and 70 sex- and age- matched normal controls were included. The global and segmental variables of work index (WI), constrictive work (CW), waste work (WW), work efficiency (WE), and CW/WW were analysed by non-invasive pressure-strain loop. Receiver operating characteristic (ROC) analysis was performed for detection the subclinical LV systolic dysfunction in T2DM patients with and without HT.ResultsThe global work index (GWI), global CW (GCW), global WE (GWE), and GCW/global WW (GWW) of T2DM and T2DM patients with HT were significantly lower than normal controls (p < 0.05). The WI, CW, WE, and CW/WW of the LV anterior wall in T2DM and T2DM patients with HT were significantly lower when compared with those of the normal controls (p < 0.05). ROC analysis showed that the value of area under the curve (AUC) in combined GWI, GCW, GWE, and GCW/GWW was significantly higher than the AUCs of the individual indices (p < 0.05).ConclusionsMW can non-invasively and accurately evaluate subclinical global and segmental LV myocardial systolic dysfunction in T2DM patients with and without HT. Regulating total cholesterol levels and controlling blood pressure in T2DM patients with and without HT might reduce the impairment of LV myocardial systolic function.

Indicators of global myocardial work of the left ventricle during exercise stress echocardiography in the diagnosis of stable coronary heart disease

Aim: To determine the possibility of identifying patients with significant coronary artery disease (CAD) by evaluation of the global left ventricular (LV) myocardial work indicators by constructing pressure-strain loops during exercise stress echocardiography.Material and Methods. The study included 136 patients aged 36 to 84 years, of which 97 (71%) men, with suspected or previously confirmed CAD, who underwent stress echocardiography on the treadmill according to the Bruce protocol. LV myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW) and global myocardial work efficiency (GWE) were evaluated using the technique of constructing pressure-strain loops at rest and at peak exercise. All patients underwent selective coronary angiography, according to the results of which they were divided into 3 groups: 51 patients without coronary artery lesions – the control group, 57 patients with single-vessel CAD and 28 patients with multi-vessel CAD. Significant lesion was defined as ≥ 70% artery luminal narrowing. All tests were two-sided and P-values &lt; 0.05 were considered statistically significant.Results. Compared with the control group, patients with single-vessel CAD at rest had significantly less GWE and more GWW. In these patients GWI, GCW and GWE at peak exercise were significantly lower, and GWW was significantly higher. In patients with multi-vessel CAD, all global LV myocardial work indicators significantly differed from the control group both at rest and at peak exercise. The optimal cutoff value of GWI at peak exercise to predict significant CAD was 2553 mmHg% with a sensitivity of 62% and a specificity of 95% (AUC 0.79 ± 0.05, p &lt; 0.001).Conclusions. The evaluation of global LV myocardial work indicators by constructing pressure-strain loops can be used in exercise stress echocardiography to improve the selection of patients requiring coronary intervention.

Left ventricular deformation in patients with lymphedema before and after the use of medical compression stockings-detailed analysis from the three-dimensional speckle-tracking echocardiographic MAGYAR-Path Study.

Lymphedema (LE) is a chronic condition, which refers to tissue swelling due to excess interstitial fluid accumulation or impaired lymphatic conduit. Theoretically, lymphedema-related fluid retention could affect left ventricular (LV) mechanics, which could be detailed by recent three-dimensional speckle-tracking echocardiography. Therefore, it was purposed to examine LV strains in LE patients before and one hour after the use of medical compression stockings and to compare findings to those of matched normal subjects. The study comprised 26 cases with lymphedema, however, 4 cases had to be excluded due to inferior quality of images. Their results were compared to 27 age- and gender-matched healthy controls. Global LV circumferential and area strains and mean segmental LV circumferential strain were increased in lymphedema patients before the use of medical compression stockings as compared to controls. One hour after the use of medical compression stockings, no global and mean segmental LV strain showed significant impairment or improvement, but tendentious reduction was seen in LV circumferential strain. With LV segmental analysis, midventricular LV radial, circumferential and area strains proved to be significantly increased, while basal LV longitudinal strain and midventricular LV three-dimensional strain were decreased as compared to controls. No changes in regional LV strains could be detected after one-hour medical compression stockings use as compared to data collected at rest. Increased global LV circumferential strain is seen in lymphedema. With using medical compression stockings, LV deformation parameters change towards the normal range emphasizing their importance on cardiac function.

Pressure overload-induced systolic heart failure is associated with characteristic myocardial microRNA expression signature and post-transcriptional gene regulation in male rats

Although systolic function characteristically shows gradual impairment in pressure overload (PO)-evoked left ventricular (LV) hypertrophy (LVH), rapid progression to congestive heart failure (HF) occurs in distinct cases. The molecular mechanisms for the differences in maladaptation are unknown. Here, we examined microRNA (miRNA) expression and miRNA-driven posttranscriptional gene regulation in the two forms of PO-induced LVH (with/without systolic HF). PO was induced by aortic banding (AB) in male Sprague–Dawley rats. Sham-operated animals were controls. The majority of AB animals demonstrated concentric LVH and slightly decreased systolic function (termed as ABLVH). In contrast, in some AB rats severely reduced ejection fraction, LV dilatation and increased lung weight-to-tibial length ratio was noted (referred to as ABHF). Global LV miRNA sequencing revealed fifty differentially regulated miRNAs in ABHF compared to ABLVH. Network theoretical miRNA-target analysis predicted more than three thousand genes with miRNA-driven dysregulation between the two groups. Seventeen genes with high node strength value were selected for target validation, of which five (Fmr1, Zfpm2, Wasl, Ets1, Atg16l1) showed decreased mRNA expression in ABHF by PCR. PO-evoked systolic HF is associated with unique miRNA alterations, which negatively regulate the mRNA expression of Fmr1, Zfmp2, Wasl, Ets1 and Atg16l1.

Left bundle branch pacing preserved left ventricular myocardial work in patients with bradycardia.

Left bundle branch pacing (LBBP) is an emerging physiological pacing modality. Left ventricular (LV) myocardial work (MW) incorporates afterload and LV global longitudinal strain to estimate global and segmental myocardial contractility. However, the effect of LBBP on LV MW remains unknown. This study aimed to evaluate the impact of LBBP on LV MW in patients receiving pacemaker for bradyarrhythmia. We prospectively enrolled 70 bradycardia patients with normal LV systolic function receiving LBBP (n = 46) and non-selective His-bundle pacing (NS-HBP) (n = 24). For comparative analysis, patients receiving right ventricular pacing (RVP) (n = 16) and control subjects (n = 10) were enrolled. Two-dimensional speckle tracking echocardiography was performed. The LV pressure-strain loop was non-invasively constructed to assess global LV MW. After 6-month follow-up, LBBP group (with >40% ventricular pacing during 6 months) had shorter peak strain dispersion (PSD) compared with RVP group, and higher LV global longitudinal strain compared with RVP group and NS-HBP group, but had no difference in left intraventricular mechanical dyssynchrony, including septal-to-posterior wall motion delay and PSD, compared with NS-HBP group. During ventricular pacing, LBBP group had higher global MW index (GWI) (2,189 ± 527 vs. 1,493 ± 799 mmHg%, P = 0.002), higher global constructive work (GCW) (2,921 ± 771 vs. 2,203 ± 866 mmHg%, P = 0.009), lower global wasted work (GWW) (211 ± 161 vs. 484 ± 281 mmHg%, P < 0.001) and higher global MW efficiency (GWE) (91.4 ± 5.0 vs. 80.9 ± 8.3%, P < 0.001) compared with RVP group, and had lower GWW (211 ± 161 vs. 406 ± 234 mmHg%, P < 0.001) and higher GWE (91.4 ± 5.0 vs. 86.4 ± 8.1%, P < 0.001) compared with NS-HBP group. In this study we found that in patients with mid-term (6-month) high ventricular pacing burden (>40%), LBBP preserved more LV MW compared with NS-HBP and RVP. Further studies are warranted to assess the association between LV MW and long-term clinical outcomes in LBBP with high ventricular pacing burden.

Biventricular Tissue Tracking with Cardiovascular Magnetic Resonance: Reference Values of Left- and Right-Ventricular Strain.

We derived reference values of left-ventricular (LV) and right-ventricular (RV) strain parameters in a cohort of 100 healthy subjects by feature tracking cardiac magnetic resonance (FT-CMR). Global and regional strain values were calculated for the LV; circumferential and radialSAX strain parameters were derived from the short-axis (SAX) stack, while longitudinal and radialLAX strain parameters were assessed in three long-axis (LAX) views. Only global longitudinal strain (GLS) was calculated for the RV. Peak global LV circumferential strain was -16.7% ± 2.1%, LV radialSAX strain was 26.4% ± 5.1%, LV radialLAX strain was 31.1% ± 5.2%, LV GLS was -17.7% ± 1.9%, and RV GLS was -23.9% ± 4.1%. Women presented higher global LV and RV strain values than men; all strain values presented a weak relationship with body surface area, while there was no association with age or heart rate. A significant association was detected between all LV global strain measures and LV ejection fraction, while RV GLS was correlated to RV end-diastolic volume. The intra- and inter-operator reproducibility was good for all global strain measures. In the regional analysis, circumferential and radial strain values resulted higher at the apical level, while longitudinal strain values were higher at the basal level. The assessment of cardiac deformation by FT-CMR is feasible and reproducible and gender-specific reference values should be used.

Early detection of reduced left ventricular systolic function by 2D speckle tracking echocardiography in patients with primary mitral regurgitation in a Vietnamese cohort.

Background: Mitral regurgitation (MR) is a common heart valve disease, causing many serious complications in several organ systems, especially the cardiovascular system. The 2D speckle tracking echocardiography (STE) is a new technique for detecting potential cardiac dysfunction when only tissue function abnormalities are present. The study aimed to assess left ventricular (LV) systolic function early by STE in patients with primary MR through global LV deformity along the global longitudinal strain (GLS). Methods: An analytical cross-sectional study was performed on 46 patients with moderate to severe primary MR as recommended by the American Society of Echocardiography (ASE) 2017. Results: The prevalence of patients with GLS reduction with ejection fraction (EF) >60%, New York Heart Association (NYHA) I, and left ventricular internal diameter systolic (LVIDs) <40mm was 38.1%, 35.7%, and 39.5%, respectively. 100% of patients with EF<60% and LVIDs ≥40mm had reduced GLS (<16%). The GLS index strongly correlates with the NYHA classification, degree of MR, EF, and echocardiographic parameters. Conclusion: GLS index gives a significant sign in the early detection of cardiac function abnormalities before symptoms or other echocardiographic parameters in patients with MR.

Impact of aortic valve stenosis on myocardial deformation in different left ventricular levels: A three-dimensional speckle tracking echocardiography study.

Global systolic left ventricular (LV) myocardial function progressively declines as degenerative aortic valve stenosis (AS) progresses. Whether this results in uniformly distributed deformation changes from base to apex has not been investigated. Eighty-five AS patients underwent three-dimensional (3D) echocardiography in this cross-sectional study. Patients were grouped by peak jet velocity into mild (n=32), moderate (n=31), and severe (n=22) AS. 3D speckle tracking derived strain, rotation, twist, and torsion were obtained to assess global LV function and myocardial function at the apical, mid, and basal levels. Global longitudinal strain (GLS) was lower in patients with severe AS (-16.1±2.4% in mild, -15.5±2.5% in moderate, and -13.5±3.0% in severe AS [all p<.01]). Peak basal and mid longitudinal strain (LS), basal rotation and twist from apical to basal level followed the same pattern, while peak apical LS was higher in moderate AS compared to severe AS (all p<.05). In multivariate analyses, lower GLS was particularly associated with male sex, higher body mass index and peak aortic jet velocity, lower basal LS with higher filling pressure (E/e') and LV mass, lower mid LS with higher RWT and presence of AS symptoms, and lower apical LS with male sex and higher systolic blood pressure, respectively (all p<.05). Using 3D speckle tracking echocardiography reveals regional and global changes in LV mechanics in AS related to the severity of AS, LV remodeling and presence of cardiovascular risk factors.

Changes in cardiac hemodynamic parameters in patients after COVID-19

Aim. To study cardiac hemodynamic disorders in patients 3, 6 and 12 months after coronavirus disease 2019 (COVID-19).Material and methods. Sixty-six patients with bilateral pneumonia (mean age, 36,1 years), treated for COVID-19, underwent echocardiography, Doppler ultrasound of hepatolienal blood flow vessels after 3, 6, 12 months. Patients were divided into groups based on computed tomography (CT) data: group 1 — 21 patients with CT1, group 2 — 25 patients with CT2, group 3 — 20 patients with CT 3-4. In the 3rd group, 60% of patients had excessive weight. IBM SPSS Statistics Version 25.0 was used.Results. Three months after the disease in all groups, there was a impairment of diastolic parameters studied on the tricuspid valve. Patients of the 3rd group had pulmonary hypertension, an increase in splenic vein diameter, and the spleen area. After 6 and 12 months. in all groups, there was an improvement in right ventricular diastolic filling. In group 3, pulmonary artery systolic pressure after 6 months decreased by 6,0 (3,7; 6,5)% (p=0,03), after 1 year by another 8,6 (5,4; 9,1)% (p=0,017). The diameter of the inferior vena cava after 6 months decreased by 4,8 (2,0; 10,2)%, and a year later by another 5,0 (4,4; 6,1)% (p=0,001); the splenic vein diameter decreased after 6 months by 7,3 (3,2; 10,4)% (p=0,005). The left ventricular (LV) global systolic strain reduced after 3, 6 and 12 months.Conclusion. All patients 3 months after COVID-19 had cardiac hemodynamic disorders, which further by 6 and 12 months tend to normalize right ventricular diastolic filling. In patients with CT 3-4, by 12 months after the disease, normalization of pulmonary artery systolic pressure was also noted, a decrease in the diameter of the inferior vena cava and splenic veins, and a decrease in the global LV systolic strain persisted.

How Often Does Apical Sparing of Longitudinal Strain Indicate the Presence of Cardiac Amyloidosis?

Echocardiographic diagnosis of cardiac amyloidosis (CA) is frequently suggested by the presence of a left ventricular (LV) apical sparing pattern (ASP) on longitudinal strain (LS) assessment, the so-called "cherry on top" pattern, defined by strain magnitude preserved exclusively at the apex. However, it is unclear how frequently this strain pattern truly represents CA. This study aimed to evaluate the predictive value of ASP in the diagnosis of CA. We retrospectively identified consecutive adult patients who had the following studies performed within an 18-month period: (1) transthoracic echocardiogram and (2) either (a) cardiac magnetic resonance imaging, (b) Technetium-Pyrophosphate (PYP) imaging, or (c) endomyocardial biopsy. LS was retrospectively measured in the apical 4-, 3-, and 2-chamber views in patients who had adequate noncontrast images (n=466). An apical sparing ratio (ASR) was calculated as (average apical strain)/[(average basal strain)+(average midventricular strain)]. Patients with ASR ≥1 were evaluated for the presence/absence of CA, using established criteria. Basic LV parameters were also measured. A total of 33 patients (7.1%) had ASP. Nine of these patients (27%) had "confirmed" CA, 2 (6.1%) "highly probable" CA, 1 (3.0%) "possible" CA, and 21 (64%) no evidence of CA. When comparing patients with and without confirmed CA, there were no significant differences in ASR, average global LS, ejection fraction, or LV mass. Patients with confirmed CA were older (76 ± 9 vs 59 ± 18years, p=0.01) and had thicker posterior wall (15 ± 3 vs 11 ± 3mm, p=0.004) with a trend toward thicker septal wall (15 ± 2 vs 12 ± 4mm, p=0.05). In conclusion, the presence of ASP on LS represents confirmed or highly probable CA in only 1/3 of patients and is more likely to indicate true CA in older patients with increased LV wall thickness. Although a larger, prospective study is needed to confirm these findings, 1/3 should be considered as a large diagnostic yield that justifies further testing, given the poor outcomes associated with CA diagnosis.

LV and LA mechanics in pediatric HCM : a CMR study of phenotype-genotype correlation

Abstract Funding Acknowledgements Type of funding sources: None. Background Paediatric hypertrophic cardiomyopathy (HCM) is a leading cause of sudden death. The relationship between the genotype variation and phenotype expression has not been fully elucidated, with some studies showing association with an increased hypertrophy and MYH7 or multiple genetic variations. In HCM fibrosis and hypertrophy contribute to left ventricular (LV) mechanics’ alteration resulting in subendocardial dysfunction. The latter is associated with a decreased global longitudinal and radial strains (GLS, GRS), whereas epicardial thickening leads to preserved global circumferential strain (GCS) and LV twist. Children with HCM have reduced LA function, measurable by both volumetric and strain analysis and reduced LA mechanics are associated with poor exercise capacity. Feature tracking –cardiac magnetic resonance (FT-CMR) has enhanced the non-invasive assessment of myocardial deformation in HCM. The main aim of our study was to assess differences of LV and LA mechanics features on CMR between patients harbouring multiple pathogenic or likely pathogenic variants (MGv, n=16) or single genetic variations (SGv, n=35). Methods Our retrospective CMR study included 51 patients (1.7–18.8 years ago). CMR data were: LV and LA’s morphological values, late gadolinium enhancement (LGE) of LA and LV walls, LV feature tracking (FT) derived strain and LV twist (LVT). LV twist was calculated as the difference between basal and apical rotation. The LA feature FT derived strain, LA conduit function, reservoir function and pump function were computed. Results In MGv group, the indexed LV mass 108.8 +/-53.0 vs 74.3+/- 22.2 in SGv (p = 0.03). LGE was present in 51% patients of the whole cohort, with LGE in 64 % of MGv group. LV FT derived strain values and LA function were not statistically significant different between groups (MGv vs SGv: GLS −15.8+/−5.3 vs −18.7+/−4.8, GCS −27.8+/8 vs −31.1+/−8.6, GRS 44.7+/−24.6 vs 62.3+/−32). LVT was reduced in MGv group (0.04+/−7.6) vs (7.4+/−7.4) in SGv (p = 0.003). LA contractile function did not differ between the groups (MGv vs SGv: GLS LA 25.1+/−14.2 vs 27.6+/−13.5). LA reservoir, conduction and pump function did not differ between the groups. LVT was significantly correlated with the LA contractile function. An increased of LVT was associated with an increased LA GLS and EF (p = 0.011; p = 0.004). Conclusions Patients with multiple genetic variants have a greater LV mass and altered LV mechanics with reduced LV twist. This study gives insights in phenotype- genotype correlation in paediatric HCM and warrants larger longitudinal studies to assess its clinical significance.

Relative dilatation of left ventricle and left atrium in patients with Parkinson disease

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): This study was supported by Czech Health Research Council AZV NU21-04-00445 and by the European Regional Development Fund - project ENOCH (No. CZ.02.1.01/0.0/0.0/16_019/0000868) Introduction Morbus Parkinson (MP) is the second most common neurodegenerative disease that progressively affects the nervous system. Accompanying heart problems may include mainly cardiovascular autonomic dysfunction. So far, very little is known about structural and functional cardiac changes in patients with MP. Purpose This pilot study aimed to analyse left ventricular (LV) and left atrial (LA) function and volumes using cardiovascular magnetic resonance (CMR). Methods In this study, 37 patients with MP (mean age 59,0 ± 8,0 years) without a history of cardiac disease or symptoms were compared to 37 sex- and age-matched control subjects without any heart disease history (mean age 54,5 ± 11,4 years). All patients underwent CMR examination at 1,5 MR scanner, including cine images for assessment of LV and LA volumetric and functional parameters. LA volumes (LAV) were measured at LV end-systole (maximum LAV - LAVmax), before the atrial contraction (pre-atrial contraction volume - LAVpac), and at late LV diastole (minimum LAV - LAVmin) and indexed (I) to the body surface area. LA strains were analysed for all LA phases: reservoir strain (LSr), conduit strain (LScd), and contractile strain (LSct). Descriptive statistics are reported as the mean (SD) or median (IQR) for normally and non-normally distributed continuous variables. All the p-values were adjusted using a false discovery rate for multiple comparisons. Results MP patients had normal global and regional systolic LV function – LV ejection fraction (EF) 65,9 ± 6,8% vs 68,9 ± 7,0% (p = NS). On the contrary, all indexed LV volumes were significantly higher in comparison to controls: LV end-diastolic volume index was 67,3 ± 12,1 ml/m2 vs 58,3 ± 11,7 ml/m2 (p = 0,013), LV end-systolic volume index was 22,0 (17,8 to 27,5) ml/m2 vs 18,9 (13,2 to 21,9) ml/m2 (p = 0,027), and LV stroke volume index was 43,8 ± 7,2 ml/m2 vs 39,8 ± 6,3 ml/m2 (p = 0,035). Similarly, indexed LAVmax and LAVpac were also relatively increased: LAVImax 42,7 ± 9,0 ml/m2 vs 35,7 ± 10,3 ml/m2 (p = 0,014), LAVIpac 29,8 ± 7,1 vs 23,8 ± 7,6 ml/m2 (p = 0,012). LAVImin was similar in both groups: 17,3 ± 5,5 ml/m2 vs 14,3 ± 6,7 ml/m2 (p = NS). LA strains were slightly lower in the MP cohort during the reservoir and conduit phase, and slightly higher in the contractile one. However, the difference did not reach statistical significance in any phase. Conclusion Patients with Parkinson´s disease have enlarged LV and LA compared to controls.

Prognostic role of left atrial morpho-functional parameters in left ventricular remodeling following acute st-elevation myocardial infarction

Abstract Funding Acknowledgements Type of funding sources: None. Background Despite prompt reperfusion and optimal medical therapy of acute ST-elevation myocardial infarction (STEMI), patients may undergo left ventricular (LV) remodeling (REM), which may lead to systolic and/or diastolic heart failure. Little is known regarding factors and mechanisms leading to LV REM, and this knowledge gap hinders potential strategies to prevent this complication. Left atrium (LA) functional and dimensional parameters are emerging as independent prognostic markers in ischemic heart disease. Purpose The present study aims at exploring the potential role of LA morpho-functional parameters by CMR-FT in predicting LV REM following STEMI. Methods This study derives from a sub-analysis of the prospective and multicenter "VavirimS" trial. All patients were assessed through 2 consecutive CMR scans, at 1 and 6 months after STEMI. CMR-FT was applied to both LA and LV. The endpoint was to evaluate the association between LA volumes and phasic functions with LV REM at 6-month follow up, defined as: i) LV REMEDV: ≥10% increase in LV end diastolic volume (EDV); ii) LV REMEDV-ESV: ≥12% increase in LV EDV and ≥6% LV end systolic volume (ESV). Results Out of 193 patients included in the VavirimS trial, 149 were enrolled and 44 have been excluded either for inadequate image quality for CMR-FT analysis or for the presence of factors impacting on LA morphology and function (i.e. mitral regurgitation and atrial fibrillation). LV REMEDV occurred in 34 patients (23%), who showed worse LA strain parameters (reservoir, conduit and booster function), LV global radial strain (GRS) and LV global circumferential epicardial strain [Fig. 1]. At multivariate analysis, LA reservoir and LV global radial strain (GRS) were confirmed as independent predictors of LV-REMEDV [Fig. 1]. The best cut-off for LA reservoir and LV GRS were 20% (sensitivity 97%; specificity 45%) and 56% (sensitivity 67%; specificity 69%), respectively. LV REMEDV-ESV occurred in 17 patients (11%), who showed reduced LA strain and LV GRS [Fig. 1]. The only independent predictor of LV remodeling in this group was LA reservoir [Fig. 1]. A subgroup analysis has been performed on two groups, according to EF: i) p-EF: preserved ejection fraction, ii) r-EF: reduced ejection fraction. In the p-EF group both LA reservoir and LV GRS were confirmed to be associated with LV REM [Fig. 1], while in the r-EF group the only independent predictor of LV REM was LV GRS [Fig. 1]. Conclusions CMR-derived LA reservoir and LV GRS are independent predictors of LV remodeling following STEMI. In patients with preserved EF LA reservoir is confirmed as independent predictor of LV remodeling, hinting at early and subclinical impairment of left chambers compliance. LA functional parameters following STEMI may help physicians in identifying patients at higher risk of LV remodeling.

Is myocardial fibrosis appropriately assessed by 2D strain derived integrated backscatter?

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Calibrated integrated backscatter (cIBS) may be obtained from bidimensional (2D) strain echocardiography as a quantification measurement of myocardial ultrasound reflectivity. Increased collagen content of the myocardium modifies tissue reflectivity and cIBS is suggested as a marker of left ventricular (LV) fibrosis. However, its diagnostic accuracy is not established. Aim To assess the correlation between cIBS by 2D strain and LV myocardial fibrosis (MF), as evaluated by non-invasive imaging and histopathology. Methods Correlation study from a cohort of 157 patients with severe symptomatic aortic stenosis (AS) referred for surgical aortic valve replacement (AVR). Patients with complete preoperative transthoracic echocardiography, cardiac magnetic resonance (CMR) and endomyocardial biopsy (EMB) obtained from the anterior basal septum at the time of AVR were selected. Two groups of 30 patients were evaluated, with and without late gadolinium enhancement (LGE) at CMR. IBS was obtained at QRS peak in decibels (dB) from both parasternal long axis (PLAX) and apical three chamber (A3C) cine clips at Qanalysis (Figure 1A). cIBS was calculated by subtracting the pericardial intensity from the average of the anteroseptal and basal inferolateral wall values. Correlation analysis was performed for the whole group of patients with global and segmental (anterior basal septum) values of native T1 and extracellular volume (ECV), and EMB collagen volume fraction (CVF) from Masson´s Trichrome staining. IBS values were compared in both group of patients. Results 60 patients (73 [68–74] years, 45% male) with high gradient (mean gradient: 64±20mmHg), normal flow (45±10mL/m2), preserved ejection fraction (60±9%) AS. Basal septal cIBS was −9.2±9.5dB and −16.3±7.9dB from A3C and PLAX views, respectively. These indexes did not correlate with basal septum thickness or global LV mass. Absolute and cIBS did not correlate neither with global and regional T1 and ECV values, nor with CVF at EMB (Figure 1B). These were not significantly different in both groups of patients and there was no correlation between cIBS values and mass of replacement MF in patients with LGE. Conclusion In these cohort of patients with classical severe AS, there was no correlation of cIBS with imaging markers of both replacement and diffuse MF. cIBS also didn´t correlate with CVF at histopathology. These findings suggest that reflectivity indexes are not suitable for myocardial tissue characterization in this setting.

Improvement in cardiac function and regional LV strain following intramyocardial injection of a theranostic hydrogel early postmyocardial infarction in a porcine model.

Myocardial infarction (MI) is often complicated by left ventricular (LV) remodeling and heart failure. We evaluated the feasibility of a multimodality imaging approach to guide delivery of an imageable hydrogel and assessed LV functional changes with therapy. Yorkshire pigs underwent surgical occlusions of branches of the left anterior descending and/or circumflex artery to create an anterolateral MI. We evaluated the hemodynamic and mechanical effects of intramyocardial delivery of an imageable hydrogel in the central infarct area (Hydrogel group, n = 8) and a Control group (n = 5) early post-MI. LV and aortic pressure and ECG were measured and contrast cineCT angiography was performed at baseline, 60 min post-MI, and 90 min post-hydrogel delivery. LV hemodynamic indices, pressure-volume measures, and normalized regional and global strains were measured and compared. Both Control and Hydrogel groups demonstrated a decline in heart rate, LV pressure, stroke volume, ejection fraction, and pressure-volume loop area, and an increase in myocardial performance (Tei) index and supply/demand (S/D) ratio. After hydrogel delivery, Tei index and S/D ratio were reduced to baseline levels, diastolic and systolic functional indices either stabilized or improved, and radial strain and circumferential strain increased significantly in the MI regions (ENrr: +52.7%, ENcc: +44.1%). However, the Control group demonstrated a progressive decline in all functional indices to levels significantly below those of Hydrogel group. Thus, acute intramyocardial delivery of a novel imageable hydrogel to MI region resulted in rapid stabilization or improvement in LV hemodynamics and function.NEW & NOTEWORTHY Our study demonstrates that contrast cineCT imaging can be used to evaluate the acute effects of intramyocardial delivery of a therapeutic hydrogel to the central MI region early post MI, which resulted in a rapid stabilization of LV hemodynamics and improvement in regional and global LV function.

Intraoperative Augmented Rotation and Circumferential Strain Compensate for Reduction of Left Ventricular Longitudinal Function After On-Pump CABG Surgery

Left ventricular (LV) longitudinal function is reduced after on-pump coronary artery bypass grafting (CABG), while global LV function often is preserved. There are only limited data on the underlying compensatory mechanism. Therefore, the authors aimed to describe intraoperative changes of LV contractile pattern by myocardial strain analysis. A prospective observational study. At a single university hospital. A total of 30 patients scheduled for isolated on-pump CABG with an uneventful intraoperative course and preoperative preserved LV and RV function, sinus rhythm, without more-than-mild heart valve disease, or elevated pulmonary pressure. Transesophageal echocardiography was performed after induction of anesthesia (T1), after termination of cardiopulmonary bypass (T2), and after sternal closure (T3). Echocardiographic evaluation was performed under stable hemodynamics, in sinus rhythm or atrial pacing, and vasopressor support with norepinephrine ≤0.1 µg/kg/min. EchoPAC v204 software (GE Vingmed Ultrasound AS, Norway) was used for analysis of 2-dimensional (2D) and 3-dimensional (3D) LV ejection fraction (EF), LV global longitudinal strain (GLS), LV global circumferential strain (GCS), LV global radial strain (GRS), LV apical rotation (aRot), LV basal rotation (bRot), and LV twist. Strain analysis was feasible in all included patients after termination of cardiopulmonary bypass (T2). Although there were no significant differences in the values of conventional echocardiographic parameters during the intraoperative interval, GLS deteriorated significantly after CABG compared to pre-bypass assessment (T1 v T2, -13.4% ± 2.9 v -11.8% ± 2.9; p=0.007). GCS improved significantly after surgery (T1 v T2, -19.4% (IQR -17.1% to -21.2%) v -22.8% (IQR -21.1% to -24.7%); p < 0.001) as well as aRot (T1 v T2, -9.7° (IQR -7.1° to -14.1°) v -14.5° (IQR -12.1° to -17.1°); p < 0.001), bRot (T1 v T2, 5.1° (IQR 3.8°-6.7°) v 7.2° (IQR 5.6°-8.2°); p=0.02), and twist (T1 v T2, 15.8° (IQR 11.7°-19.4°) v 21.6° (IQR 19.2°-25.1°); p < 0.001), while GRS remained unchanged. There were no significant changes in the values of GLS, GCS, GRS, aRot, bRot, or twist, as well as in the values of 2D and 3D LV EF before and after sternal closure (T2 v T3). Beyond evaluation of longitudinal LV strain, measurements of circumferential and radial strain, as well as LV rotation and twist mechanics, were feasible in the intraoperative course of this study. Reduction of longitudinal function after on-pump CABG was compensated intraoperatively by improvement of GCS and rotation in the authors' group of patients. Perioperative assessment of GCS, GRS, as well as rotation and twist, might provide deeper insight into perioperative changes of cardiac mechanics.

LV and LA mechanics in pediatric HCM: A CMR study of phenotype-genotype correlation

The relationship between the genotype variation and phenotype expression in paediatric hypertrophic cardiomyopathy (HCM) has not been fully elucidated. In HCM, fibrosis and hypertrophy contribute to left ventricular (LV) mechanics with a decreased global longitudinal and radial strains (GLS, GRS). The epicardial thickening leads to preserved global circumferential strain (GCS) and LV twist. Feature tracking – cardiac magnetic resonance (FT-CMR) has enhanced the non-invasive assessment of myocardial deformation in HCM. The aim of our study was to assess differences of LV and LA mechanics features on CMR between patients harbouring multiple pathogenic or likely pathogenic variants (MGv, n = 16) or single genetic variations (SGv, n = 35). Our retrospective CMR study included 51 patients (1.7–18.8 years ago). CMR data were: LV and LA's morphological values, late gadolinium enhancement (LGE) of LA and LV walls, LV feature tracking (FT) derived strain and LV twist (LVT). LV twist was calculated as the difference between basal and apical rotation. The LA feature FT derived strain and function's parameters were computed. In MGv group, the indexed LV mass 108.8–53.0 vs. 74.3 ± 22.2 in SGv (P = 0.03). LGE was present in 51% patients of the whole cohort, with LGE in 64% of MGv group. LV FT derived strain values were not statistically significant different between groups (MGv vs. SGv: GLS −15.8 ± 5.3 vs. −18.7 ± 4.8, GCS −27.8 ± 8 vs. −31.1 ± 8.6, GRS 44.7 ± 24.6 vs. 62.3 ± 32). LVT was reduced in MGv group (0.04 ± 7.6) vs. (7.4 ± 7.4) in SGv (P = 0.003). LA contractile function did not differ between the groups. Patients with multiple genetic variants have a greater LV mass and altered LV mechanics with reduced LV twist. This study gives insights in phenotype-genotype correlation in paediatric HCM and warrants larger longitudinal studies to assess its clinical significance (Fig. 1).

PE-454609-1 MYOCARDIAL WORK IN VENTRICULAR PREEXCITATION

Ventricular preexcitation alters the electromechanical activation sequence and may induce left ventricular (LV) contractile discoordination and pathologic remodelling in selected cases. To evaluate LV myocardial work before and after accessory pathway (AP) ablation in patients with WPW preexcitation and to compare them to normal controls. Mechanical activation mapping and myocardial work calculation was performed in 11 pediatric patients with the WPW syndrome/pattern and left sided or paraseptal APs undergoing catheter ablation (successful in 10/11) and 8 healthy age-matched controls using speckle tracking echocardiography and the GE ECHOPAC version 204.57.0.745 software with the integrated AFI module. An 18-segmental echocardiographic LV model was used. Global LV myocardial work efficiency (GWE) was calculated as the ratio of global constructive work to the sum of global constructive and global wasted work (GWW). The time from delta wave onset to R wave peak in lead V6 (delta to R) was used to quantify the degree of preexcitation. Before ablation GWW was higher (164 vs 102 mmHg%, P=0.015) and GWE lower (median 91 vs 94%, P=0.010) in patients vs controls. After successful ablation GWW decreased from 164 to 93 mmHg% (P=0.006) and GWE increased from 91.1 to 94.0 % (P=0.006). GWE tended to correlate negatively with the delta to R interval (R=0.59, P=0.056). Before ablation, segmental WE increased with distance from ventricular AP insertion from median 69.5 % at AP location to 98.0 % in distant segments (P<0.001). After ablation, WE was equally distributed among LV segments (Figure). Mechanical activation mapping localized APs with a median (IQR) segmental distance of 0 (0-1) segments from the EP mapped location. Ventricular preexcitation induces significant LV myocardial work inefficiency in segments adjacent to AP which correlates with the degree of preexcitation and is normalized after ablation. The amount of wasted work in asymptomatic preexcitation may be considered when assessing the potential for pathologic LV remodelling or discussing the indication for prophylactic ablation. Mechanical activation mapping may be used to localize manifest APs.

CI-452767-4 NON-INVASIVE 3D ELECTRICAL ACTIVATION MAPPING TO PREDICT CRT RESPONSE: SITE OF LATEST LV ACTIVATION RELATIVE TO PACING SITE

Left ventricular (LV) pacing remote to the latest LV electrically activated site (LEAS) may diminish efficacy of cardiac resynchronization therapy (CRT). However, this has not been evaluated rigorously using global LV mapping. Test whether the distance “dp” between LV pacing site (LVPS) and LEAS influences the rate of CRT response. Consecutive CRT patients in 5 centers underwent noninvasive 3D electrical activation mapping and torso CT 6-24 months post-implant. LVPS, LEAS and dp were assessed. LV end-systolic volume (LVESV) reduction of ≥15% at clinical follow-up defined response. Logistic regression probabilistically modeled Non-Response; variables included demographics, heart failure classification, left bundle branch block (LBBB), ischemic heart disease, atrial fibrillation (AF), baseline QRS duration, baseline ejection fraction (EF), baseline LVESV, comorbidities, use of CRT optimization algorithm, ACE inhibitor/ARB, beta-blocker, diuretics, and dp. Of 111 patients (age 64 ± 11 years, baseline LVEF 28 ± 6%, baseline QRS duration 172 ± 21 ms, baseline LVESV 183 ± 87 mL, implant duration 12 ± 5 months (mean ± SD); 93%/7% had class I/IIa CRT indication, 31%/69% had NYHA Class II/III, 74% were males, 98% had LBBB, 38% had ischemic heart disease and 18% had a history of AF), 67% responded at 10 ±3 months post-implant (55% and 75% for ischemic and non-ischemic patients, respectively). LEAS were outside the mid and basal lateral segments in 35% of the patients. dp was 42 ± 23 mm (range 2-137): 31 ± 14 mm in Responders vs 63 ± 24 mm in Non-Responders. The distance dp, and the use of CRT optimization algorithms, remained the only independent predictors of non-response (area under the curve (AUC) 0.906). dp = 47 mm delineated Responders from Non-Responders (AUC 0.931). The distance between LV pacing site and site of latest electrical activation is a strong independent predictor for CRT response. Non-invasive electrical evaluation to characterize intrinsic activation and guide LV lead deployment may improve CRT efficacy.