Left Ventricular Myocardial Volume Research Articles

S-100β level is closely associated with myocardial work in patients with acute ischemic stroke

BackgroundThe more severe the acute stroke is, the more serious myocardial damage is. This study aimed to determine the relationship between myocardial work and S100β, a quantitative biomarker of active cerebral lesions, in patients with acute ischemic stroke (AIS). MethodsA total of 63 patients with AIS were examined by myocardial work echocardiography, 4D echocardiography with the measurement of left ventricular (LV) myocardial work, volume and function within 24-48 h of symptom onset, respectively. Their plasma S100β was measured from a peripheral blood sample within 2-6 h of symptom onset. ResultsPatients with elevated S-100β level had significantly increased ratios of peak early diastolic transmitral filling velocity to peak early diastolic lateral mitral annulus tissue velocity(E/e’) and global longitudinal strain (GLS), and significantly reduced global work index(GWI) and global constructive work (GCW) compared with those with normal S-100β level (p < 0.05). S-100β positively correlated with E/e’(r = 0.878, p < 0.0001) and GLS (r = 0.511, p = 0.002) but negatively correlated with GWI(r = −0.409, p = 0.034) and GCW(r = −0.353, p = 0.041). S-100β showed an excellent ability to differentiate if a reduced GWI [cut-off value, 120.79 pg/mL; area under receiver operating characteristic curve (AUC), 1.000; sensitivity, 100%; specificity, 100%], GCW (cut-off value, 120.79 pg/mL;AUC,1.000; sensitivity,100%; specificity, 100%) and an increased E/e’ (cut-off value, 91.1 pg/mL;AUC,0.913; sensitivity,80%; specificity, 100%) or not, but poor ability to differentiate if an increased GLS(cut-off value, 91.1 pg/mL; AUC,0.576; sensitivity,63.64%; specificity, 83.33%) or not. ConclusionS-100β level is closely associated with LV function. It is highly competent in determining an impaired myocardial work in patients with AIS.

Predictive value of left ventricular global function index in patients with aortic stenosis

A number of factors has an impact on the survival prognosis in aortic stenosis patients. One of these factors is a left ventricular (LV) systolic function. Left ventricular global function index (LVGFI) takes into account the components of LV remodeling: LV volume, LV stroke volume, and LV myocardial volume.Objective: to evaluate the prognostic value of LVGFI in patients with various aortic stenosis severity using echocardiography.Material and methods. The study based on the data of previous prospective observational study from 2010–2016, followed by retrospective calculation and analysis of the LVGFI obtained by echocardiography. A total of 377 patients were included to the study, the average age was 79 (75–84) years; 128 (34%) of them were male; 70 patients (19%) had mild aortic stenosis, 116 patients (31%) moderate aortic stenosis, and 191 patients (50%) severe aortic stenosis. LVGFI was calculated as the percentage ratio of LV stroke volume to LV global volume, where LV global volume was defined as the sum of the LV mean cavity volume [(LV end-diastolic volume + LV end-systolic volume)/2] and the myocardium volume. LV myocardial volume was calculated as the ratio of LV myocardial mass to LV density (defined as 1.05 g/mL). The average follow-up period at the moment of analysis was 602.7 ± 48.72 days. All cases of death during the period of follow up were captured.Results. The significant differences of LVGFI obtained between surviving and deceased patients (15.39% (11.35–20.95%) and 20.12% (15.16–25.98%), respectively, p &lt; 0.001). Values of LVGFI &lt; 18% significantly associated with the risk of death from all causes during two years of follow-up in both mild aortic stenosis and moderate and severe aortic stenosis.Conclusion. Thus, in patients with aortic stenosis in the group of fatal outcomes the values of the LVGFI were significantly lower than in the group of surviving patients. LVGFI values of less than 18% associated with the risk of death from all causes in any grade of aortic stenosis. LVGFI can be used for mortality risk stratification in patients with aortic stenosis.

Impact of myocardial bridge defined by computed tomographic coronary angiography on fractional flow reserve after elective percutaneous coronary intervention

Abstract Background Myocardial bridge (MB) is a common anomaly of epicardial coronary artery that courses through myocardium. MB can be identified by computed tomographic coronary angiography (CTCA) or invasive coronary angiography (ICA). However, its relevance to coronary physiological parameters remains unknown. Purpose This observational study aimed to explore how MBs affect physiological parameters in patients with chronic coronary syndrome before and after revascularization. Methods We investigated 172 consecutive patients who underwent preprocedural CTCA and elective fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) in left anterior descending artery (LAD). We compared patient characteristics, angiographic, and pre- and post-PCI physiological parameters in patients with versus without MB. Results We identified MB in 70 (40.7%) and 23 (13.3%) patients by CTCA and ICA, respectively. CTCA detected the presence of MB with a sensitivity of 100% and a specificity of 33% when ICA-defined MB was regarded as a reference standard. Longer MB (adjusted odds ratio 1.18 [95% confidence interval 1.05-1.33], P &amp;lt; 0.01) and smaller left ventricular myocardial mass volume in whole LAD territory (adjusted odds ratio 0.93 [95% confidence interval 0.89-0.98], P&amp;lt;0.01) were associated with ICA detectability of MB. Older age and higher frequency of diabetes mellitus were observed in patients with MB compared with those without MB. Pre-PCI FFR values were not associated with a presence of MB regardless of either CTCA- or ICA-defined MB. On the other hand, post-PCI FFR values were significantly lower in patients with versus without MB by CTCA (0.82 [0.80-0.86] vs. 0.86 [0.82-0.89], P&amp;lt;0.01), while no significant difference was observed in post-PCI FFR between patients with and without ICA-defined MB (0.82 [0.81-0.84 vs. 0.84 [0.80-0.88], P=0.08). Multivariable linear regression analysis revealed that a presence of CTCA-defined long MB (≥25mm) (adjusted β coefficient = -0.040, P&amp;lt;0.01) and greater myocardial mass volume in whole LAD territory (adjusted β coefficient = -0.0004, P&amp;lt;0.01) were independently associated with lower post-PCI FFR. Conclusion A presence of MB was an independent predictor of lower post-PCI FFR after successful and elective PCI for LAD.

Quantification of Myocardial Contraction Fraction with Three-Dimensional Automated, Machine-Learning-Based Left-Heart-Chamber Metrics: Diagnostic Utility in Hypertrophic Phenotypes and Normal Ejection Fraction.

Aims: The differentiation of left ventricular (LV) hypertrophic phenotypes is challenging in patients with normal ejection fraction (EF). The myocardial contraction fraction (MCF) is a simple dimensionless index useful for specifically identifying cardiac amyloidosis (CA) and hypertrophic cardiomyopathy (HCM) when calculated by cardiac magnetic resonance. The purpose of this study was to evaluate the value of MCF measured by three-dimensional automated, machine-learning-based LV chamber metrics (dynamic heart model [DHM]) for the discrimination of different forms of hypertrophic phenotypes. Methods and Results: We analyzed the DHM LV metrics of patients with CA (n = 10), hypertrophic cardiomyopathy (HCM, n = 36), isolated hypertension (IH, n = 87), and 54 healthy controls. MCF was calculated by dividing LV stroke volume by LV myocardial volume. Compared with controls (median 61.95%, interquartile range 55.43-67.79%), mean values for MCF were significantly reduced in HCM-48.55% (43.46-54.86% p < 0.001)-and CA-40.92% (36.68-46.84% p < 0.002)-but not in IH-59.35% (53.22-64.93% p < 0.7). MCF showed a weak correlation with EF in the overall cohort (R2 = 0.136) and the four study subgroups (healthy adults, R2 = 0.039 IH, R2 = 0.089; HCM, R2 = 0.225; CA, R2 = 0.102). ROC analyses showed that MCF could differentiate between healthy adults and HCM (sensitivity 75.9%, specificity 77.8%, AUC 0.814) and between healthy adults and CA (sensitivity 87.0%, specificity 100%, AUC 0.959). The best cut-off values were 55.3% and 52.8%. Conclusions: The easily derived quantification of MCF by DHM can refine our echocardiographic discrimination capacity in patients with hypertrophic phenotype and normal EF. It should be added to the diagnostic workup of these patients.

Longitudinal Changes in the Myocardial T1 Relaxation Time, Extracellular Volume Fraction, and Left Ventricular Function in Asymptomatic Men.

(1) Background: Longitudinal changes in myocardial T1 relaxation time are unknown. We aimed to assess the longitudinal changes in the left ventricular (LV) myocardial T1 relaxation time and LV function. (2) Methods: Fifty asymptomatic men (mean age, 52.0 years) who underwent 1.5 T cardiac magnetic resonance imaging twice at an interval of 54 ± 21 months were included in this study. The LV myocardial T1 times and extracellular volume fractions (ECVFs) were calculated using the MOLLI technique (before and 15 min after gadolinium contrast injection). The 10-year Atherosclerotic Cardiovascular Disease (ASCVD) risk score was calculated. (3) Results: No significant differences in the following parameters were noted between the initial and follow-up assessments: LV ejection fraction (65.0 ± 6.7% vs. 63.6 ± 6.3%, p = 0.12), LV mass/end-diastolic volume ratio (0.82 ± 0.12 vs. 0.80 ± 0.14, p = 0.16), native T1 relaxation time (982 ± 36 vs. 977 ± 37 ms, p = 0.46), and ECVF (24.97 ± 2.38% vs. 25.02 ± 2.41%, p = 0.89). The following parameters decreased significantly from the initial assessment to follow-up: stroke volume (87.2 ± 13.7 mL vs. 82.6 ± 15.3 mL, p = 0.01), cardiac output (5.79 ± 1.17 vs. 5.50 ± 1.04 L/min, p = 0.01), and LV mass index (110.16 ± 22.38 vs. 104.32 ± 18.26 g/m2, p = 0.01). The 10-year ASCVD risk score also remained unchanged between the two timepoints (4.71 ± 0.19% vs. 5.16 ± 0.24%, p = 0.14). (4) Conclusion: Myocardial T1 values and ECVFs were stable over time in the same middle-aged men.

Myocardial Contraction Fraction as a Simple Marker of Disease Severity in Hypertrophic Cardiomyopathy

Purpose: Myocardial contraction fraction (MCF) of cardiac magnetic resonance (CMR) was used to evaluate myocardial function in patients with hypertrophic cardiomyopathy (HCM), which may represent a proxy marker of disease severity in HCM. Materials and Methods: A total of 60 HCM patients and 20 healthy controls were examined with CMR. MCF was calculated by dividing left ventricular stroke volume by left ventricular myocardial volume. The difference in MCF between late gadolinium enhancement (LGE)-positive and LGE-negative patients were compared. The differences in MCF were compared among patients with stages Ⅱ, Ⅲ, and Ⅳ of HCM. Logistic regression analysis was used to detect independent discriminants of more severe HCM. Receiver operating characteristic analysis differentiated HCM with different clinical stages. Results: Compared with controls (110.67±20.40%, P&lt;0.001), values for MCF were significantly reduced in HCM (61.40±15.60%). The MCF reduction in LGE detected by CMR was more significant than in HCM patients without LGE (53.15±10.67% vs. 76.72±11.04%, P&lt;0.001). Patients with stage IV of HCM had the lowest MCF (45.36±10.97%, P&lt;0.05 vs. stage II and III). Lower MCF remains an independent discriminator for more severe HCM (Stage Ⅱ vs. Stage Ⅲ, odds ratio: 0.85; Stage Ⅲ vs. Stage Ⅳ, odds ratio: 0.88, all P&lt;0.05). The optimal cutoff value for detecting more severe HCM is MCF under 66.40% (Stage Ⅱ vs. Stage Ⅲ, P&lt;0.05) and 44.75% (Stage Ⅲ vs. Stage Ⅳ, P&lt;0.05). Conclusion: MCF may be a useful and simple tool to evaluate myocardial function in patients with HCM and provide an indicator of disease severity in individuals with HCM.

Heart failure with preserved ejection fraction in post myocardial infarction patients: a myocardial magnetic resonance (MR) tissue tracking study.

This study aimed to explore the value of cardiac magnetic resonance tissue tracking (CMR-TT) technology in evaluating heart failure with preserved ejection fraction (HFpEF) in patients with chronic myocardial infarction (CMI). Between June 2016 and March 2022, we included a consecutive series of 92 patients with CMI and 40 healthy controls in this retrospective study. The CMI patients enrolled were divided into different subgroups [HFpEF-CMI group (n=54) and non- heart failure (HF)-CMI group (n=38)] according to the Heart Failure Association (HFA)-PEFF (step 1: P, pre-test assessment; step 2: E, echocardiography and natriuretic peptide score; step 3: F1, functional testing; step 4: F2, final aetiology) diagnostic algorithm. CMR scan was performed at the First Hospital of China Medical University. Quantitative measurements of myocardial damage, such as myocardial strain parameters of both ventricles derived by CMR-TT and infarct size and transmurality by late gadolinium enhancement (LGE), were assessed. One-way analysis of variance, independent samples t-test, and rank sum test were used to compare myocardial impairment among groups. Pearson or Spearman correlation coefficient was used to measure correlations between left ventricular (LV) strains and clinical and functional parameters. Logistic regression analysis and receiver operating characteristic (ROC) curve were performed to identify the best parameter for diagnosing HFpEF-CMI. HFpEF-CMI patients demonstrated significantly impaired LV strains and strain rates in all of the three directions (radial, circumferential and longitudinal) compared to non-HF-CMI patients and healthy controls (P<0.001 for all), whereas only global longitudinal strain (GLS) was significantly impaired in HFpEF-CMI patients vs. controls for right ventricular strain parameters (P<0.001). LV strains showed moderate correlation with N-terminal pro-brain natriuretic peptide (radial, circumferential and longitudinal strain, R=-0.401, R=0.408, R=0.407, respectively, P<0.001 for all). LV strains in the three directions (radial, circumferential and longitudinal) [area under ROC curve (AUC) =0.707, 95% confidence interval (CI): 0.603-0.797; AUC =0.708, 95% CI: 0.604-0.798; AUC =0.731, 95% CI: 0.628-0.818; respectively, P<0.01 for all] were discriminators for HFpEF-CMI and non-HF-CMI. LV strains and myocardial infarction volume were independent factors in multi-logistic regression analysis after adjusting for body mass index, age, and sex (P<0.05 for all). CMR-TT provides clinicians with useful additional imaging parameters to facilitate the assessment of CMI patients with HFpEF. LV strain parameters can detect early cardiac insufficiency in patients with HFpEF-CMI and have potential value for discriminating between HFpEF and non-HF patients post-CMI.

Hemoglobin A1c in type 2 diabetes mellitus patients with preserved ejection fraction is an independent predictor of left ventricular myocardial deformation and tissue abnormalities

Background Early detection of subclinical myocardial dysfunction in patients with type 2 diabetes mellitus (T2DM) is essential for preventing heart failure. This study aims to search for predictors of left ventricular (LV) myocardial deformation and tissue abnormalities in T2DM patients with preserved ejection fraction by using CMR T1 mapping and feature tracking.Methods 70 patients and 44 sex- and age-matched controls (Cs) were recruited and underwent CMR examination to obtain LV myocardial extracellular volume fraction (ECV) and global longitudinal strain (GLS). The patients were subdivided into three groups, including 19 normotensive T2DM patients (G1), 19 hypertensive T2DM patients (G2) and 32 hypertensive patients (HT). The baseline biochemical indices were collected before CMR examination.Results LV ECV in T2DM patients was significantly higher than that in Cs (30.75 ± 3.65% vs. 26.33 ± 2.81%; p < 0.05). LV GLS in T2DM patients reduced compared with that in Cs (−16.51 ± 2.53% vs. −19.66 ± 3.21%, p < 0.001). In the subgroup analysis, ECV in G2 increased compared with that in G1 (31.92 ± 3.05% vs. 29.59 ± 3.90%, p = 0.032) and that in HT, too (31.92 ± 3.05% vs. 29.22 ± 6.58%, p = 0.042). GLS in G2 significantly reduced compared with that in G1 (−15.75 ± 2.29% vs. −17.27 ± 2.57%, p < 0.05) and in HT, too (−15.75 ± 2.29% vs. −17.54 ± 3.097%, p < 0.05). In T2DM group, including both G1 and G2, hemoglobin A1c (HbA1c) can independently forecast the increase in ECV (β = 0.274, p = 0.001) and decrease in GLS (β = 0.383, p = 0.018).ConclusionsT2DM patients with preserved ejection fraction show increased ECV but deteriorated GLS, which may be exacerbated by hypertension of these patients. Hemoglobin A1c is an index that can independently predict T2DM patients’ LV myocardial deformation and tissue abnormalities.

Prognostic role of the left ventricular global function index in predicting major adverse cardiovascular events in acute coronary syndrome patients.

Aim: This study aimed to evaluate the prognostic role of the left ventricular (LV) global function index (LVGFI) in predicting major adverse cardiovascular events in patients with acute coronary syndrome after long-term follow-up. Methods: This retrospective study included 718 patients with ST-elevated myocardial infarction (STEMI) and 781 patients with non-ST-elevated myocardial infarction (NSTEMI). The LVGFI was calculated on echocardiography with the following formula: (LV stroke volume/[LV cavity volume + LV myocardial volume]) ×100. Results: Mean LVGFI was higher in the NSTEMI group than in the STEMI group. Decreased LVGFI levels were independent predictors of major adverse cardiovascular events in both the STEMI and the NSTEMI group. Conclusion: Echocardiographic LVGFI may be a useful prognostic screening tool for acute coronary syndrome cohorts.

Magnetic resonance diagnostic criteria of non-compaction cardiomyopathy: new diagnostic criteria still needed?

Summary Non-compaction cardiomyopathy (NCC) is a rare pathology, but the exact rates of its prevalence are not known due to the lack of a diagnostic gold standard. The purpose of this article is to analyse the available cardiovascular magnetic resonance (CMR) diagnostic criteria of non-compaction described in the literature and to compare their sensitivity and specificity in the diagnosis of NCC. A search of available literature related to the CMR diagnostic criteria of myocardial non-compaction was conducted in the medical database PubMed in February of 2022. The period of publication of scientific articles covered the years from 1996 to 2022. A total of 7 full-text scientific articles were included in the final literature review. The main diagnostic criteria were used: the maximum non-compact (NCM) to compact myocardial layers (CM) ratio (NCM:CM), the percentage of trabeculated left ventricular (LV) myocardial mass, the percentage of trabeculated LV myocardial volume, the non-compact myocardial mass index of the total LV, and the determination of the total LV and the maximal fractal dimension (FD) of the apex with the use of fractal analysis. The lack of accurate diagnostic criteria results in an overdiagnosis of NCC. The highest sensitivity and specificity are associated with the maximum FD &gt; 1.30 of the apex established by applying the fractal analysis method. Fractal analysis requires dedicated software, and this method is difficult to apply in routine clinical practice. Thus, the diagnostic criteria for the NCC using magnetic resonance imaging with higher diagnostic value remain to be sought.

Abstract 12077: Impact of Overweight and Obesity on Left Ventricular Structure and Function in a Community Dwelling Cohort Free of Cardiovascular Disease

Introduction: Obesity is associated with excess cardiovascular morbidity and mortality as well as structural and functional differences in left ventricular (LV) mass (LVM), end-diastolic volume (LVEDV), and stroke volume despite indexation. Hypothesis: We hypothesize that overweight and obesity impact LV structure and function in a healthy community dwelling cohort. Methods: Framingham Offspring study participants (N=678, 62%F; 65±9y) free of any history of hypertension, myocardial infarction, heart failure, or CMR wall-motion abnormality and underwent bSSFP CMR at 1.5T. They were stratified by sex and body mass index (BMI) category (normal weight =18.5 to 24.9; overweight =25.0 to 29.9; obese ≥30 kg/m 2 ). LVM was measured from contiguous short-axis images, then indexed to height (HT, m), body surface area (BSA, m 2 ), and weight (WT, kg). We calculated myocardial contraction fraction (MCF), a marker of LV myocardial shortening, as LV stroke volume divided by LV myocardial volume. The ratio of LVM/LVEDV was used as a measure of LV concentricity to evaluate LV structure. Results: The Table shows MCF, LV concentricity, and indexed LVM (LVMi) stratified by BMI. WT-indexation resulted in a declining LVMi with increasing BMI in both men and women. However, indexation to HT showed an increasing LVMi with higher BMI. BSA-indexation remained consistent across BMI categories in both men and women. MCF decreased and concentricity increased with increasing BMI in both sexes. Conclusion: The association of LVMi with BMI varies by indexation method. In a healthy, community-dwelling cohort, BSA yields “consistent” LVM indexation across BMI categories. However, MCF decreased, and concentricity increased with increasing categories of BMI. These adverse alterations of MCF and concentricity may provide insight into obesity-related LV remodeling, whereas consideration of LVM alone may not. These data lay the groundwork for further outcomes analyses in this population.

Abstract 13367: APOE ε4 Carriage Associates With Improved Myocardial Performance in Older Age

Introduction: Although APOE ε 4 allele carriage confers a risk of coronary disease, its persistence in human populations might be explained by certain survival advantages (antagonistic pleiotropy) . Hypothesis: Combining data from two British cohorts– the 1946 National Survey of Health and Development (NSHD) and Southall and Brent Revised (SABRE)–we explored whether APOE ε 4 carriage associates with beneficial or unfavorable left ventricular (LV) structural and functional echocardiography parameters in older age. Methods: Based on the presence of APOE ε 4, genotypes were divided into: APOE ε 4 (ε2ε4, ε3ε4, ε 4 ε 4) and non- APOE ε 4 carriers. Echocardiographic data included: LV ejection fraction, E/e’, systolic and diastolic posterior wall and interventricular septal thickness (LVPWT s/d , IVS s/d ), LV mass and the ratio of the LV stroke volume to the LV myocardial volume called myocardial contraction fraction (MCF). Generalized linear models explored associations between APOE ε 4 genotypes as exposures and echocardiographic biomarkers as outcomes. As APOE genotype is a genetic instrumental variable (unconfounded), Model 1 was unadjusted. Model 2 was adjusted for factors associated with the outcome (sex and socio-economic position) to yield more precise estimates; subsequent models were individually adjusted for mediators (body mass index, cardiovascular disease [CVD], high cholesterol and hypertension) to explore mechanistic pathways. Random-effects meta-analyses were performed across the cohorts. Results: 2596 participants were included. Compared to non- APOE ε 4 carriers, APOE ε 4 carriers had similar cardiac phenotypes in terms of EF, E/e’, LVPWT s/d , IVS s/d and LV mass but had a 4% higher MCF (95% confidence interval [CI]: 1–7%, p =0.016) which persisted in Model 2 (95% CI 1–7%, p =0.008) but was attenuated to 3% after adjustment for CVD, diabetes and hypertension (all 95% CI 0–6% all p &lt;0.070). Conclusions: APOE ε 4 carriage associates with improved myocardial performance in older age resulting in greater LV stroke volume generation per 1 mL of myocardium. This potentially favorable cardiac phenotype adds to the growing number of reported survival advantages attributed to APOE ε4 carriage that might collectively explain its persistence in humans.

Female sex and systolic blood pressure are independently associated with coronary microvascular dysfunction in asymptomatic adults with type 2 diabetes

Abstract Introduction Coronary microvascular dysfunction is frequently reported in people with type 2 diabetes (T2D), is associated with reduced exercise capacity, and is a prognostic marker. Identifying modifiable risk factors associated with microvascular dysfunction may facilitate early intervention to improve outcomes in these patients. Purpose To identify independent determinants of myocardial perfusion reserve (MPR) in asymptomatic adults with T2D and no prevalent cardiovascular disease. Methods Prospective cross-sectional study. People with and without T2D and no signs, symptoms or evidence of cardiovascular disease underwent comprehensive phenotyping with echocardiography, coronary artery calcium scoring, and multiparametric cardiac MRI including adenosine stress and rest perfusion with automated pixel-wise myocardial blood flow (MBF) mapping. Participants with regional perfusion defects indicating obstructive coronary disease or silent myocardial infarct on late-gadolinium enhancement were excluded from analysis. Univariable and multivariable linear regression was performed to identify independent determinants of MPR. Results Two-hundred people with T2D (diabetes duration 11±8 years) were compared with 39 sex- and ethnicity-matched non-diabetic controls (Table 1). People with T2D had higher body mass index (BMI) and ambulatory 24-hour systolic blood pressure (SBP). There was evidence of concentric left ventricular (LV) remodelling (higher LV mass/volume), extracellular matrix expansion (higher ECV fraction), and both systolic and diastolic dysfunction (lower global longitudinal systolic strain and E/A ratio, respectively) in those with T2D. Resting MBF was similar between groups, but stress MBF tended to be lower in T2D compared to controls with significantly reduced MPR in T2Ds (2.87±0.86 vs 3.18±0.82, p=0.043). In univariable analysis, MPR correlated with sex, 24-hour SBP, and E/e' ratio. In a multivariable model adjusting for clinical (age, sex, smoking status, BMI, ambulatory SBP, diabetes duration, HbA1c, low-density lipoprotein, albuminuria) and imaging variables (E/e' ratio, LV mass/volume, global longitudinal strain, myocardial ECV, coronary calcium score) known to affect coronary perfusion, female sex (β=−0.227, p=0.013) and 24-hour SBP (β=−0.275, p=0.001) were the only variables independently associated with MPR. Conclusion Female sex is associated with coronary microvascular dysfunction in asymptomatic people with T2D but not LV mass or myocardial extracellular volume. Systolic BP is the only modifiable independent determinant of MPR and may be an early target for intervention to prevent heart failure development in these patients. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): National Institute for Health Research (NIHR) United Kingdom through a Research Professorship award (RP-2017-08-ST2-007).British Heart Foundation through a Clinical Research Training Fellowship award (FS/16/47/32190).

Left and right ventricular function alterations in obstructive sleep apnea patients assessed by 2D speckle tracking echocardiography

Abstract Introduction Obstructive sleep apnea (OSA) is related to increased left ventricular (LV) transmural pressure, blood pressure instability and increased pulmonary artery pressure (PAP) leading to left and right ventricular (RV) dysfunction and heart failure. 2D speckle tracking echocardiography (STE) is useful method for subclinical biventricular dysfunction diagnosis, thus might help to earlier treatment for OSA patients. Purpose The aim of the study was to evaluate changes of biventricular function and mechanics in patients with OSA. Methods We obtained 2D STE from 47 obese patients. 13 patients either did not have OSA, or it was mild (apnea/hypopnea index (AHI) 5–14/hour). OSA group (N=34) consisted of subjects with moderate or severe OSA (AHI ≥15/hour). New indexing for LV myocardial mass and LA volume by height was applied according new guidelines for obese patients. Statistical analyses were performed using the SPSS 27.0 software. The value of p&amp;lt;0.05 was considered as statistically significant. Results BMI did not differ between groups (p=0.108). Control group patients were younger, had higher female ratio, meanwhile arterial hypertension was more prevalent in OSA group (26 (76.5%) vs. 5 (38.5%), p=0.014). New indexing by height for left ventricular myocardial mass revealed higher LV MMi in OSA patients (p=0.007), and higher prevalence of LV diastolic dysfunction (p=0.023) was found in this group of patients. Moreover, LA reservoir function was significantly lower in OSA group compared to controls p&amp;lt;0.001. LV ejection fraction and conventional RV function parameters (s', fractional area change (FAC)) did not differ between groups, however LV and RV global longitudinal strain was reduced in OSA patients (p=0.035 and p=0.026, respectively). OSA patients had significantly higher RA diameter, and mean PAP (p=0.043 and p=0.037, respectively) (Table 1). Conclusions Moderate or severe obstructive sleep apnea is related to reduced biventricular longitudinal strain, more prevalent LV diastolic dysfunction and lower LA reservoir function. New indexing for LV myocardial mass by height helps to identify myocardial structural changes in obese patients with OSA. Funding Acknowledgement Type of funding sources: None.

Left ventricular remodeling following septal myectomy in hypertrophic obstructive cardiomyopathy

ObjectivesThe purpose of this study is to determine whether or not left ventricular remodeling can be induced after septal myectomy in patients with obstructive hypertrophic cardiomyopathy, and if so, how it occurs, using gated cardiac computed tomography. MethodsFifty patients with hypertrophic obstructive cardiomyopathy who underwent septal myectomy along the septal band between March 2016 and July 2020 were retrospectively reviewed. Recent consecutive 19 patients underwent postoperative cardiac computed tomography. In these patients, volumes of the septal band and thickness of 17 left ventricular myocardial segments were measured to determine the changes after surgery. ResultsThe resection volume predicted by preoperative computed tomography and the actual resection volume were 6.7 ± 3.3 mL and 6.4 ± 2.7 mL. In-hospital mortality was 0%. Moderate or greater mitral valve regurgitation and systolic anterior motion decreased from 56% to 6% and 86% to 6%, respectively. Median preoperative ventricular septal thickness and left ventricular outflow tract pressure gradient at rest decreased from 20.0 mm (interquartile range, 17.0-24.0 mm) and 74.0 mm Hg (interquartile range, 42.5-92.5 mm Hg) to 14.0 mm (interquartile range, 11.5-16.0 mm) and 15.5 mm Hg (interquartile range, 12.1-21.5 mm Hg), respectively. Postoperative computed tomography confirmed a reduction in septal band volume of 5.7 ± 2.8 mL. Total left ventricular myocardial volume was reduced by 12.9 ± 8.8 mL, which exceeded the volume reduction of the resected septal band. All segments except the basal inferior and basal inferolateral regions showed a significant decrease in wall thickness by a median of 6.4%. ConclusionsProperly performed septal myectomy may induce remodeling of the entire left ventricle, not just the resected area.

Electrophysiologic Conservation of Epicardial Conduction Dynamics After Myocardial Infarction and Natural Heart Regeneration in Newborn Piglets.

Newborn mammals, including piglets, exhibit natural heart regeneration after myocardial infarction (MI) on postnatal day 1 (P1), but this ability is lost by postnatal day 7 (P7). The electrophysiologic properties of this naturally regenerated myocardium have not been examined. We hypothesized that epicardial conduction is preserved after P1 MI in piglets. Yorkshire-Landrace piglets underwent left anterior descending coronary artery ligation at age P1 (n = 6) or P7 (n = 7), After 7 weeks, cardiac magnetic resonance imaging was performed with late gadolinium enhancement for analysis of fibrosis. Epicardial conduction mapping was performed using custom 3D-printed high-resolution mapping arrays. Age- and weight-matched healthy pigs served as controls (n = 6). At the study endpoint, left ventricular (LV) ejection fraction was similar for controls and P1 pigs (46.4 ± 3.0% vs. 40.3 ± 4.9%, p = 0.132), but significantly depressed for P7 pigs (30.2 ± 6.6%, p < 0.001 vs. control). The percentage of LV myocardial volume consisting of fibrotic scar was 1.0 ± 0.4% in controls, 9.9 ± 4.4% in P1 pigs (p = 0.002 vs. control), and 17.3 ± 4.6% in P7 pigs (p < 0.001 vs. control, p = 0.007 vs. P1). Isochrone activation maps and apex activation time were similar between controls and P1 pigs (9.4 ± 1.6 vs. 7.8 ± 0.9 ms, p = 0.649), but significantly prolonged in P7 pigs (21.3 ± 5.1 ms, p < 0.001 vs. control, p < 0.001 vs. P1). Conduction velocity was similar between controls and P1 pigs (1.0 ± 0.2 vs. 1.1 ± 0.4 mm/ms, p = 0.852), but slower in P7 pigs (0.7 ± 0.2 mm/ms, p = 0.129 vs. control, p = 0.052 vs. P1). Overall, our data suggest that epicardial conduction dynamics are conserved in the setting of natural heart regeneration in piglets after P1 MI.

Myocardial contraction fraction by echocardiography and mortality in cardiac intensive care unit patients

BackgroundThe myocardial contraction fraction (MCF) is proposed as an improved measure of left ventricular (LV) systolic function that overcomes important limitations of the left ventricular ejection fraction (LVEF). We sought to determine whether a low MCF was associated with higher mortality in cardiac intensive care unit (CICU) patients. MethodsWe retrospectively analyzed unique Mayo Clinic CICU patients from 2007 to 2018 with MCF calculated as the ratio of the stroke volume to the left ventricular myocardial volume from a transthoracic echocardiogram within 1 day of CICU admission. Multivariable logistic regression analyzed the association between MCF and hospital mortality, after adjustment for LVEF and clinical variables. ResultsWe included 4794 patients with a mean age of 68.0 ± 14.8 years (37.1% females). The mean MCF was 0.41 ± 0.16, and was lower in the 6.6% of patients who died in the hospital (0.32 ± 0.14 versus 0.42 ± 0.16, p < 0.001). On multivariable analysis, higher MCF remained associated with lower hospital mortality (adjusted OR 0.78 per 0.1 higher, 95% CI 0.69–0.89, p < 0.001), whereas LVEF was not significantly associated with hospital mortality (unadjusted OR 0.91 per 10% higher, OR 95% CI 0.82–1.02, p = 0.09). Patients with MCF <0.2 had the highest in-hospital mortality, and those with MCF ≥0.5 had the lowest in-hospital mortality, irrespective of admission diagnosis or LVEF. ConclusionsMCF demonstrated a strong, inverse relationship with hospital mortality in CICU patients, even after adjusting for LVEF and clinical variables. MCF can be used to identify prognostically-relevant myocardial dysfunction at the bedside, even among patients with preserved LVEF.

Comprehensive assessment of myocardial remodeling in ischemic heart disease by synchrotron propagation based X-ray phase contrast imaging

Cardiovascular research is in an ongoing quest for a superior imaging method to integrate gross-anatomical information with microanatomy, combined with quantifiable parameters of cardiac structure. In recent years, synchrotron radiation-based X-ray Phase Contrast Imaging (X-PCI) has been extensively used to characterize soft tissue in detail. The objective was to use X-PCI to comprehensively quantify ischemic remodeling of different myocardial structures, from cell to organ level, in a rat model of myocardial infarction. Myocardial infarction-induced remodeling was recreated in a well-established rodent model. Ex vivo rodent hearts were imaged by propagation based X-PCI using two configurations resulting in 5.8 µm and 0.65 µm effective pixel size images. The acquired datasets were used for a comprehensive assessment of macrostructural changes including the whole heart and vascular tree morphology, and quantification of left ventricular myocardial thickness, mass, volume, and organization. On the meso-scale, tissue characteristics were explored and compared with histopathological methods, while microstructural changes were quantified by segmentation of cardiomyocytes and calculation of cross-sectional areas. Propagation based X-PCI provides detailed visualization and quantification of morphological changes on whole organ, tissue, vascular as well as individual cellular level of the ex vivo heart, with a single, non-destructive 3D imaging modality.

Combined protocol for remote ischemic conditioning as the method of cardioprotection in patients with acute ST-segment elevation myocardial infarction

Background. There is currently no commonly accepted strategy for limiting the reperfusion injury that occurs after revascularization in patients with myocardial infarction. This study aimed to investigate the efficacy of a promising cardioprotective method.Material and Methods. Patients with acute anterior ST-segment elevation myocardial infarction (STEMI) (n = 87) were included in an open-label prospective randomized controlled trial. Control group comprised patients with STEMI who underwent only primary percutaneous coronary intervention (PPCI) (n = 44). Patients of intervention group (n = 43) underwent PPCI and remote ischemic perconditioning combined with postconditioning (RIC). The efficacy of RIC was assessed based on cardiac magnetic resonance (CMR) imaging data.Results. The medians of left ventricular (LV) infarct size were significantly higher in patients of control group: 44.8 (33.6; 55.5) versus 52.7 (35.5; 73.9) mL (p = 0.039) at day 10 after STEMI and 34.0 (25.8; 39.8) mL versus 46.0 (32.8; 55.0) mL six months after STEMI in control and intervention groups, respectively (p = 0.004). The groups of patients did not differ in the sizes of area at risk relative to the total LV myocardial volume: 40 (35; 45) and 43 (34; 49)% in control and intervention groups, respectively (р = 0.232). The groups significantly differed in the ratios of infarct size to area at risk: 70.3 (65.1; 86.6)% in control group versus 63.5 (52.7; 72.0)% in intervention group (р = 0.014) as well as in the myocardial salvage indexes: 29.7 (13.5; 34.9)% in control group versus 36.5 (28.0; 47.3)% in intervention group (р = 0.014). The study showed the tendency to greater LV myocardial salvage in intervention group versus control group at six-months follow-up (р = 0.073). The groups significantly differed in the medians of microvascular obstruction volume: 1.9 (1.4; 2.9) mL in intervention group versus 2.5 (1.8; 8.1) mL in control group (p = 0.049) as well as in the proportions of microvascular obstruction in the LV myocardium: 0.94 (0.79; 1.37)% in intervention group versus 1.50 (0.89; 3.66)% in control group (р = 0.046).Conclusion. The RIC method combined with PPCI contributed to the limitation of infarct and microvascular obstruction sizes and was associated with an increase in the myocardial salvage index in STEMI patients.

Myocardial Function in Premenopausal Women Treated With Ovarian Function Suppression and an Aromatase Inhibitor

BackgroundPremenopausal women with high-risk hormone receptor (HR)-positive breast cancer often receive ovarian function suppression (OFS) with aromatase inhibitor therapy; however, abrupt menopause induction, together with further decrements in estrogen exposure through aromatase inhibition, may affect cardiovascular microcirculatory function. We examined adenosine-induced changes in left ventricular (LV) myocardial T1, a potential subclinical marker of LV microcirculatory function in premenopausal women undergoing treatment for breast cancer.MethodsTwenty-one premenopausal women (14 with HR-positive breast cancer receiving OFS with an aromatase inhibitor and 7 comparator women with triple-negative breast cancer [TNBC] who had completed primary systemic therapy) underwent serial resting and adenosine cardiovascular magnetic resonance imaging measurements of LV myocardial T1 and LV volumes, mass, and ejection fraction. All statistical tests were 2-sided.ResultsAfter a median of 4.0 months (range = 3.1-5.7 months), the stress to resting ratio of LV myocardial T1 declined in women with HR-positive breast cancer (−1.3%, 95% confidence interval [CI] = −3.4% to 0.7%) relative to those with TNBC (3.2%, 95% CI = −1.2% to 7.6%, P = .02). After accounting for age, LV stroke volume, LV ejection fraction, diastolic blood pressure, and breast cancer subtype women with HR-positive breast cancer experienced a blunted T1 response after adenosine relative to women with TNBC (difference = −4.7%, 95% CI = −7.3% to −2.1%, Pdifference = .002).ConclusionsOver the brief interval examined, women with HR-positive breast cancer receiving OFS with an aromatase inhibitor experienced reductions in adenosine-associated changes in LV myocardial T1 relative to women who received nonhormonal therapy for TNBC. These findings suggest a possible adverse impact on LV myocardial microcirculatory function in premenopausal women with breast cancer receiving hormone deprivation therapy.