Left Ventricular Stroke Volume Research Articles

Comparison of echocardiographic and catheter methods in the diagnosis of severe aortic valve stenosis

Purpose. 1. Assess the consistency of echocardiographic measurements with catheterization data in severe aortic stenosis. Assess if inter-method consistency improves after adjusting scores for the pressure recovery factor. To identify factors affecting the consistency of echocardiography and catheterization data. Materials and methods. Prospectively, 70 patients (mean age 72 ± 6 years, 38 females) have been included. All patient underwentcardiac catheterization with single-meter echoscanning of the parameters necessary to assess the severity of aortic valve stenosis before transcatheter aortic valve implantation. Inclusion criteria were isolated aortic stenosis (EOA <1 cm2, Gmax ≥64 mm Hg, Gmean ≥40 mm Hg. Exclusion criteria were LV stroke volume index <35 ml/m 2 and a reduced EF <50%, concomitant nontrivial regurgitation of the aortic and mitral valves. Result. The linear regression method showed a weak correlation between the G max (Doppler) and P mean indices, r = 0.48, p = 0.001. Revealed high values of the average difference between the two methods in comparison with the Blent–Altman (SR 19 ± 17 mm Hg.) and low intraclasscorrelation values (ICC = 0.34). After adjusting the Gmax (Doppler) indices for the pressure recovery factor, the correlation between the methods r = 0.84, p ≤ 0.001, significantly improved. There was a decrease in the mean indices, the difference between the two HR methods was (3.15 ± 12 mm Hg.) with highly significant intraclasscorrelation values (ICC = 0.89). Similarly, a low correlation with high values of the average difference was observed when comparing EOA (Doppler) and EOA (catheterization) r = 0.55, p = 0.01, SR 0.21 ± 0.15 cm 2 , ICC = 0.53. With an improvement in the correlation between the methods after adjustment for the pressure recovery coefficient, r = 0.9, p ≤ 0.001, CP = 0.04 ± 0.08 cm 2 , ICC = 0.92. Comparison of Gmean (Doppler) indices with catheter Pmean has showed a high correlation between the methods, r = 0.7, p ≤ 0.001, there were relatively low indices of the average difference between the two methods of HR = 7.2 ± 22 mm Hg and a significant intraclass correlation (ICC = 0.72). The method of analysis of multiple regression revealed that the diameter of the sinotubular ridge was a significant factor affecting the correlation between echocardiography and catheterization data, OR 1.2 (CI 0.09; 2.9). Conclusions The maximum Doppler gradient (G max ) and the effective orifice area (EOA) have low consistency and weak correlation with catheterization data, in contrast to the average Doppler gradient (G mean ) which have a high consistency with catheterization data. After correcting for pressure recovery factor, there is a significant improvement in the consistency between G max and EOA with catheterization data. The diameter of the sinotobular junction is a significant factor influencing the consistency of echocardiography and catheterization data, which must be taken into account when assessing the severity of aortic stenosis.

Hypersensitivity of Zebrafish htr2b Mutant Embryos to Sertraline Indicates a Role for Serotonin Signaling in Cardiac Development.

Selective serotonin reuptake inhibitors (SSRIs) are antidepressants prescribed in 10% of pregnancies in the United States. Maternal use of SSRIs has been linked to an elevated rate of congenital heart defects, but the exact mechanism of pathogenesis is unknown. Previously, we have shown a decrease in cardiomyocyte proliferation, left ventricle size, and reduced cardiac expression of the serotonin receptor 5-HT 2B in offspring of mice exposed to the SSRI sertraline during pregnancy, relative to offspring of untreated mice. These results suggest that disruption of serotonin signaling leads to heart defects. Supporting this conclusion, we show here that zebrafish embryos exposed to sertraline develop with a smaller ventricle, reduced cardiomyocyte number, and lower cardiac expression of htr2b relative to untreated embryos. Moreover, zebrafish embryos homozygous for a nonsense mutation of htr2b ( htr2bsa16649 ) were sensitized to sertraline treatment relative to wild-type embryos. Specifically, the ventricle area was reduced in the homozygous htr2b mutants treated with sertraline compared with wild-type embryos treated with sertraline and homozygous htr2b mutants treated with vehicle control. Whereas long-term effects on left ventricle shortening fraction and stroke volume were observed by echocardiography in adult mice exposed to sertraline in utero, echocardiograms of adult zebrafish exposed to sertraline as embryos were normal. These results implicate the 5-HT 2B receptor functions in heart development and suggest zebrafish are a relevant animal model that can be used to investigate the connection between maternal SSRI use and elevated risk of congenital heart defects.

Association of MMP1 and MMP3 haplotypes with myocardial infarction and echocardiographic parameters of the left ventricle.

BackgroundMyocardial infarction (MI) leads to ischemia and afterward to left ventricular (LV) remodeling. Matrix metalloproteinase−1 (MMP1) and −3 (MMP3) belong to the family of endopeptidases and together they can dissolve most of the components of the extracellular matrix. MMP1 and MMP3 variants have been investigated solely in association with ischemic heart disease and LV dysfunction, but not in haplotype. The aims of this study were to investigate the association of haplotypes inferred from MMP1 rs1799750 (−1607 1G/2G; NC_000011.9:g.102670497del) and MMP3 rs35068180 (−1612 5A/6A; NC_000011.9:g.102715952dup) with MI and their effect on the change in echocardiographic parameters of LV structure and function in patients within 6 months after MI.MethodsThe study included 325 patients with the first MI and 283 healthy controls. Gene variants were detected by PCR‐RFLP method. Parameters of LV structure and function were assessed by conventional 2D echocardiography, 3–5 days and 6 months after the first MI, on a subgroup of 160 patients. Haplotype analysis was performed with Thesias software.ResultsHaplotypes 2G‐5A and 1G‐6A were significantly and independently associated with MI compared with the reference haplotype 2G‐6A (adjusted, p = 0.009 and p = 0.026, respectively). After Bonferroni correction for multiple testing, MMP1 and MMP3 haplotypes lost their association with the change in LV long diameter and stroke volume within 6 months after MI.Conclusion MMP1 and MMP3 haplotypes are strongly associated with MI. Further studies are needed to validate this result and to examine their association with echocardiographic parameters of LV structure and function after MI.

Echocardiographic Investigation of Low-Flow State in a Hispanic/Latino Population

ObjectiveTo assess the prevalence of low-flow state (LFS) with left ventricular (LV) stroke volume index of less than 35 mL/m2 and the demographics, clinical and echocardiographic characteristics associated with LV remodeling and function in a Hispanic/Latino population. Participants and MethodsThe study included 1346 asymptomatic participants from the Hispanic Community Health Study/Study of Latinos with normal LV ejection fraction (≥55%) and no valvular heart disease. LV volume, mass and left atrial volume, LV ejection fraction, global longitudinal strain, and myocardial contraction fraction were measured by echocardiography. The participants were divided into LFS or normal flow state (NFS: stroke volume index ≥35 mL/m2). Demographics, clinical and echocardiographic characteristics, and measures of LV remodeling and function were compared between the LFS and NFS groups. ResultsThe prevalence of LFS was 41%. In comparison with NFS, the LFS had lower LV mass index (77.2±0.96 g/m2 vs 84.6±0.86 g/m2; P<.001), left atrial volume index (20.6±0.35 mL/m2 vs 23.5±0.37 mL/m2; P<.001), global longitudinal strain (−16.8±0.16% vs −17.7±0.17%; P<.001), and myocardial contraction fraction (43.3±0.63% vs 55.7±0.64%; P<.001). There was no significant difference in the relative wall thickness (LFS: 0.40±0.004 vs NFS: 0.40±0.005; P=.57). The LFS group had significantly higher hemoglobin A1c (6.18±0.07% vs 5.97±0.04%; P=.01) than the NFS group. ConclusionA high prevalence of LFS associated with echocardiographic characteristics reflecting unfavorable LV remodeling and function was observed in a Hispanic/Latino population. Further studies of the prognostic significance of LFS in a large multiethnic population are warranted.

Heart failure with reduced, mildly reduced, or preserved left ventricular ejection fraction: Has reasoning been lost?

Left ventricular (LV) ejection fraction (LVEF), defined as LV stroke volume divided by end-diastolic volume, has been systematically used for the diagnosis, classification, and management of heart failure (HF) over the last three decades. HF is classified as HF with reduced LVEF, HF with midrange or mildly reduced LVEF, and HF with preserved LVEF using arbitrary, continuously changing LVEF cutoffs. A prerequisite for using this LVEF-based terminology is knowledge of the LVEF normal range, which is lacking and may lead to erroneous conclusions in HF, especially at the higher end of the LVEF spectrum.

Supranormal Left Ventricular Ejection Fraction, Stroke Volume, and Cardiovascular Risk: Findings From Population-Based Cohort Studies

BackgroundSupranormal ejection fraction by echocardiography in clinically referred patient populations has been associated with an increased risk of cardiovascular disease (CVD). The prognostic implication of supranormal left ventricular ejection fraction (LVEF)—assessed by cardiac magnetic resonance (CMR)—in healthy, community-dwelling individuals is unknown. ObjectivesThe purpose of this study is to investigate the prognostic implication of supranormal LVEF as assessed by CMR and its inter-relationship with stroke volume among community-dwelling adults without CVD. MethodsParticipants from the MESA (Multi-Ethnic Study of Atherosclerosis) and DHS (Dallas Heart Study) cohorts free of CVD who underwent CMR with LVEF above the normal CMR cutoff (≥57%) were included. The association between cohort-specific LVEF categories and risk of clinically adjudicated major adverse cardiovascular events (MACE) was assessed using adjusted Cox models. Subgroup analysis was also performed to evaluate the association of LVEF and risk of MACE among individuals stratified by left ventricular stroke volume index. ResultsThe study included 4,703 participants from MESA and 2,287 from DHS with 727 and 151 MACE events, respectively. In adjusted Cox models, the risk of MACE was highest among individuals in LVEF Q4 (vs Q1) in both cohorts after accounting for potential confounders (MESA: HR = 1.27 [95% CI: 1.01-1.60], P = 0.04; DHS: HR = 1.72 [95% CI: 1.05-2.79], P = 0.03). A significant interaction was found between the continuous measures of LVEF and left ventricular stroke volume index (P interaction = 0.02) such that higher LVEF was significantly associated with an increased risk of MACE among individuals with low but not high stroke volume. ConclusionsAmong community-dwelling adults without CVD, LVEF in the supranormal range is associated with a higher risk of adverse cardiovascular outcomes, particularly in those with lower stroke volume.

Is There a Correlation Between Left Ventricular Outflow Tract Velocity Time Integral and Stroke Volume Index in Patients Undergoing Cardiac Surgery?

IntroductionLeft ventricular outflow tract velocity time integral (LVOT VTI) is a promising surrogate for stroke volume (SV). However, there is controversy in the literature regarding its correlation with thermodilution or newer cardiac output measurement techniques. This study was conducted to determine the correlation between LVOT VTI determined by transesophageal echocardiography (TEE) with stroke volume index (SVI) calculated by thermodilution.MethodsConsecutive patients older than 17 years undergoing elective cardiac surgery with pulmonary artery catheter (PAC) and TEE monitoring between September 2021 and February 2022 were included in this prospective, descriptive, single-center study. LVOT VTI was measured using TEE after induction of anesthesia but before skin incision and at least four hours after initial LVOT VTI measurement. SVI was simultaneously measured using the continuous thermodilution technique with a PAC. The correlation between LVOT VTI and SVI was determined with Pearson’s correlation index.ResultsTwelve patients were included and 21 paired measurements were compared. Mean SVI was 31.62 ± 10.71 mL/m2 and mean LVOT VTI was 14.74 ± 4.79 cm. The Pearson's correlation index for the two measurements was r = 0.257, p = 0.262.ConclusionThis prospective study demonstrated a weak correlation between LVOT VTI and SVI in patients undergoing cardiac surgery.

Left ventricular venting during extracorporeal membrane oxygenation; the effects on cardiac performance in a porcine model of critical post-cardiotomy failure.

Left ventricular distension is a major concern with postcardiotomy veno-arterial extracorporeal membrane oxygenation (VA-ECMO) supporting a critical heart failure after cardiac surgery. This porcine study evaluates the effects of left ventricular venting on cardiac function during ECMO-supported circulation and after weaning from ECMO. Twenty anaesthetised open-chest pigs were put on cardiopulmonary bypass with aortic cross-clamping and suboptimal cardioplegic arrest for 40min. After declamping and defibrillation, the animals were supported by VA-ECMO for 180min either with or without additional left ventricular venting. Continuous haemodynamic evaluations were performed at baseline and at cardiac arrest, during VA-ECMO and for 120min after weaning from circulatory support. Left ventricular perfusion and function were evaluated with microspheres, pressure-volume loops and epicardial echocardiography at baseline and after 1 and 2h with unsupported circulation. In vented animals both mean aortic and left ventricular peak systolic pressure increased at the end of the ECMO-supported period compared to those not vented and remained increased also after weaning. Both at 60 min and 120min after weaning from circulatory support, left ventricular stroke work and pressure-volume area were increased in vented compared to not vented animals. At 120min left ventricular stroke volume was increased in vented compared to not vented animals, myocardial perfusion did not differ. The left ventricular mechanical efficiency, defined as the ratio between pressure volume area and myocardial perfusion, was increased (53.2 ± 5 vs 36.2 ± 2.1J/mL/g, p = 0.011) in vented- compared to not vented hearts. This experimental study demonstrate that left ventricular venting during post-cardiotomy veno-arterial ECMO for 3h attenuates deterioration of left ventricular function and haemodynamics early after weaning from circulatory support.

Transthoracic Echocardiography to Assess Post-Resuscitation Left Ventricular Dysfunction After Acute Myocardial Infarction and Cardiac Arrest in Pigs

One of the main causes of out-of-hospital cardiac arrest is acute myocardial infarction (AMI). After successful resuscitation from cardiac arrest, approximately 70% of patients die before hospital discharge due to post-resuscitation myocardial and cerebral dysfunction. In experimental models, myocardial dysfunction after cardiac arrest, characterized by an impairment in both left ventricular (LV) systolic and diastolic function, has been described as reversible but very little data are available in cardiac arrest models associated with AMI in pigs. Transthoracic echocardiography is the first-line diagnostic test for the assessment of myocardial dysfunction, structural changes and/or AMI extension. In this pig model of ischemic cardiac arrest, echocardiography was done at baseline and 2-4 and 96 hours after resuscitation. In the acute phase, the examinations are done in anesthetized, mechanically ventilated pigs (weight 39.8 ± 0.6 kg) and ECG is recorded continuously. Mono- and bi-dimensional, Doppler and tissue Doppler recordings are acquired. Aortic and left atrium diameter, end-systolic and end-diastolic left ventricular wall thicknesses, end-diastolic and end-systolic diameters and shortening fraction (SF) are measured. Apical 2-, 3-, 4-, and 5-chamber views are acquired, LV volumes and ejection fraction are calculated. Segmental wall motion analysis is done to detect the localization and estimate the extent of myocardial infarction. Pulsed Wave Doppler echocardiography is used to record trans-mitral flow velocities from a 4-apical chamber view and trans-aortic flow from a 5-chamber view to calculate LV cardiac output (CO) and stroke volume (SV). Tissue Doppler Imaging (TDI) of LV lateral and septal mitral anulus is recorded (TDI septal and lateral s', e', a' velocities). All the recordings and measurements are done according to the recommendations of the American and European Societies of Echocardiography Guidelines.

Combining echo-derived haemodynamic phenotypes and myocardial strain for risk stratification of chronic heart failure with reduced ejection fraction.

Echocardiography has shown to categorize heart failure (HF) patients according to haemodynamic profiles. Whether left ventricular (LV) global longitudinal strain (LV-GLS) could integrate echo-derived haemodynamic profiles to risk stratify chronic HF patients is still unknown. Chronic HF outpatients with LV ejection fraction (LV-EF) <50% (n = 351) and LV-GLS assessment were evaluated and divided according to four haemodynamic phenotypes based on LV stroke volume index (SVI), LV filling pressure (LVFP), and right ventricular (RV) function: normal output-normal LVFP (NO-NP), normal output-high LVFP (NO-HP), low output-no RV dysfunction (LO-NRVD), and low output-RV dysfunction (LO-RVD). RV function was defined using the tricuspid annular plane systolic excursion and RV free-wall longitudinal strain. The median follow-up duration was 3.3 years. The combination of all-cause mortality and HF hospitalization was the primary endpoint. Secondary endpoints were all-cause mortality and cardiovascular mortality. The prevalence of NO-NP, NO-HP, LO-NRVD, and LO-RVD were 38%, 22%, 30%, and 10%, respectively. The haemodynamic model independently predicted primary and secondary outcomes, with incremental prognostic information over LV-EF (all P-values <0.001 for C-statistics). When univariate Cox regression analysis was performed to assess the prognostic stratification capability of LV-GLS in different haemodynamic subgroups, we observed a reduction in LV-GLS hazard ratios from the NO-NP to the LO-RVD for every endpoint. There was a continuum in LV-GLS impairment across the spectrum of haemodynamic phenotypes and its prognostic value resulted variable depending on the types of chronic HF patients. The highest prognostic information added by LV-GLS was in patients with normal SVI.

3.0T cardiac magnetic resonance quantification of native T1 and myocardial extracellular volume for the diagnosis of late gadolinium enhancement-negative cardiac amyloidosis.

BackgroundLate gadolinium enhancement (LGE) by cardiac magnetic resonance (CMR) is useful for the detection of cardiac amyloidosis (CA), but characteristic LGE patterns do not always occur or they appear late in the disease. Native T1 and extracellular volume (ECV) by T1 mapping may improve disease detection and quantify myocardial amyloid load.MethodsThirty patients with definite CA, 10 patients with possible CA, 20 patients with hypertrophic cardiomyopathy (HCM) and 40 healthy volunteers were performed 3.0-T CMR including cine, pre- and postcontrast T1 mapping and LGE. Receiver-operating characteristic (ROC) curves were constructed to assess the diagnostic ability of native T1 and ECV for CA. Correlation analysis between native T1 or ECV and cardiac biomarkers, structure, and function indexes were assessed using Pearson or Spearman correlation, as appropriate.ResultsNative T1 values were 1,429±93, 1,290±49, 1,304±42, and 1,225±21 ms, in definite CA, possible CA, HCM, and healthy controls, respectively. ECV values were 44%±9%, 34%±5%, 33%±4%, and 24%±3%, in definite CA, possible CA, HCM, and healthy controls, respectively. Native T1 [area under curve (AUC) =0.89, 95% confidence interval (CI): 0.75–1.00, P<0.001] and ECV (AUC =0.99, 95% CI: 0.98–1.00, P<0.001) showed good ability to differentiate LGE-negative patients with possible CA from healthy controls, especially ECV. Positive correlations were found between native T1 or ECV and New York Heart Association (NYHA) functional class (r=0.673 and r=0.594, respectively; P<0.001), NT-proBNP (r=0.668 and r=0.603, respectively; P<0.001), troponin T (r=0.724 and r=0.591, respectively; P<0.001), left ventricular (LV) mass index (r=0.668 and r=0.579, respectively; P<0.001), and global LV wall thickness (r=0.765 and r=0.629, respectively; P<0.001). Negative correlations were found between native T1 or ECV and left ventricular ejection fraction (LVEF) (r=−0.761 and r=−0.668, respectively; P<0.001) and left ventricular stroke volume (LVSV) (r=−0.777 and r=−0.729, respectively; P<0.001).ConclusionsNative T1 and ECV, which are able to reflect cardiac biochemistry, structure, and function, have high diagnostic accuracy for detecting CA, especially in LGE-negative patients, and thus could be used for early diagnosis of CA.

Validation of Artificial Intelligence Cardiac MRI Measurements: Relationship to Heart Catheterization and Mortality Prediction.

Background Cardiac MRI measurements have diagnostic and prognostic value in the evaluation of cardiopulmonary disease. Artificial intelligence approaches to automate cardiac MRI segmentation are emerging but require clinical testing. Purpose To develop and evaluate a deep learning tool for quantitative evaluation of cardiac MRI functional studies and assess its use for prognosis in patients suspected of having pulmonary hypertension. Materials and Methods A retrospective multicenter and multivendor data set was used to develop a deep learning-based cardiac MRI contouring model using a cohort of patients suspected of having cardiopulmonary disease from multiple pathologic causes. Correlation with same-day right heart catheterization (RHC) and scan-rescan repeatability was assessed in prospectively recruited participants. Prognostic impact was assessed using Cox proportional hazard regression analysis of 3487 patients from the ASPIRE (Assessing the Severity of Pulmonary Hypertension In a Pulmonary Hypertension Referral Centre) registry, including a subset of 920 patients with pulmonary arterial hypertension. The generalizability of the automatic assessment was evaluated in 40 multivendor studies from 32 centers. Results The training data set included 539 patients (mean age, 54 years ± 20 [SD]; 315 women). Automatic cardiac MRI measurements were better correlated with RHC parameters than were manual measurements, including left ventricular stroke volume (r = 0.72 vs 0.68; P = .03). Interstudy repeatability of cardiac MRI measurements was high for all automatic measurements (intraclass correlation coefficient range, 0.79-0.99) and similarly repeatable to manual measurements (all paired t test P > .05). Automated right ventricle and left ventricle cardiac MRI measurements were associated with mortality in patients suspected of having pulmonary hypertension. Conclusion An automatic cardiac MRI measurement approach was developed and tested in a large cohort of patients, including a broad spectrum of right ventricular and left ventricular conditions, with internal and external testing. Fully automatic cardiac MRI assessment correlated strongly with invasive hemodynamics, had prognostic value, were highly repeatable, and showed excellent generalizability. Clinical trial registration no. NCT03841344 Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Ambale-Venkatesh and Lima in this issue. An earlier incorrect version appeared online. This article was corrected on June 27, 2022.

Complete anatomic surgical myocardial revascularisation during postinfarction ventricular septal defect and ventricular aneurysm repair is associated with improved short- and long-term outcomes.

Coronary artery bypass grafting (CABG) is recommended during acute postinfarction ventricular septal defect (PIVSD) repair, but clinical benefits of surgical revascularization in patients with subacute PIVSD have not been established. We aimed to evaluate the association of primary complete anatomic surgical myocardial revascularization (CASMR) during PIVSD and ventricular aneurysm (VA) repair on patients' short- and long-term outcomes. This was a retrospective observational study. The inclusion criterion was PIVSD. Patients with previous CABG and those with PIVSD due to vasospasm and normal coronary arteries on angiography were excluded. From March 2002 to April 2021, 53 patients met the eligibility criteria. The median patient age was 65 years, and 28 (53%) were male. Compared to the non-CABG group, CABG patients had higher values of the median postoperative left ventricular (LV) end-diastolic volume, 100 ml, and 128.5 ml, respectively (p = .012), and the mean LV stroke volume, 49 ml, and 61 ml, respectively (p = .048). The mortality rates in the CABG and non-CABG groups were 3.6/100 person-years (95% confidence interval [CI]: 1.5-8.6/100 person-years) and 16.3/100 person-years (95% CI: 8.5-31.3/100 person-years), respectively. Cox regression adjusted for between groups imbalances demonstrated a 4-fold greater mortality risk (hazard ratio = 4.3; 95% CI: 1.1-16.7; p = .036) among the non-CABG patients than in the CABG patients. Kaplan-Meier survival analysis yielded a poorer overall survival of the non-CABG patients (p = .011). Primary CASMR during PIVSD and VA repair is associated with improved postoperative cardiac function, lower hospital mortality, and better long-term survival. We recommend CASMR during PIVSD and VA repair.

Machine learning models for accurate pretreatment prediction of chemotherapy associated LV dysfunction in patients with breast cancer and lymphoma receiving chemotherapy (WF-98213 PREVENT and CCCWFU9912 DETECT IV).

1553 Background: Cancer survivors receiving potentially cardiotoxic chemotherapy are at increased risk for developing left ventricular (LV) dysfunction. We implemented machine learning (ML) models to predict future LV dysfunction in patients with breast cancer or lymphoma scheduled to receive potentially cardiotoxic chemotherapy. Methods: We utilized prospectively collected data from NIH studies R01HL118740 (supported by the Wake Forest NCORP Research Base (UG1CA189824)) and R01CA167821. Data included measurements of LV function and demographic factors before, during, and 24 months after initiating potentially cardiotoxic chemotherapy. The two datasets were used both separately and collectively in the development of multiple ML models including penalized linear regression, support vector machine, and random forest (RF). A data preprocessing step properly handled missing information, data imbalance, and encoding. Hyperparameter tuning was performed using cross validation of training data. The final models were assessed with a 20% hold-out test dataset. Cardiotoxicity was defined as a pre- to 24-month post cancer treatment decline in LV ejection fraction (LVEF) of &gt; 10% or to an absolute value of &lt; 50%. Results: 276 patients were included in ML models (7% men, 93% women; age 52±13 years). The RF model based on the combined dataset had the best performance with a prediction accuracy, sensitivity, and specificity of 0.94, 0.81, and 0.98, respectively. The most important variables assessed pre-treatment as measured by the Gini impurity factor were in descending order, LVEF, global LV circumferential strain, LV end-systolic volume, body mass index, LV stroke volume, LV end-diastolic volume, and LV mass. Conclusions: Prior to cancer treatment, supervised ML methods such as RF models predicted declines in LVEF of &gt; 10% and/or to absolute values below 50% would occur 24 months after initiating chemotherapy for breast cancer or lymphoma. With further improvement and validation using larger datasets, these models may play an important role in cardio-oncology care during and following cancer treatment.

CARD19: In vitro and In vivo Testing of the Pulsatile CorWave Membrane LVAD

Background: Lack of physiologic pulsatility with the use of continuous flow (CF) LVADs has been associated with serious adverse events including stroke, bleeding, and aortic insufficiency. CorWave is developing a unique LVAD employing an undulating membrane to generate a physiologic pulse while improving hemocompatibility. The present studies focused on in vitro and in vivo testing of the pump control algorithms for hemodynamic performance and hemocompatibility. Methods: The pump actuator, membrane, and blood flow path were designed using respectively electromagnetic simulations (MAGNET), Fluid-Structure Interaction (COMSOL), and Computational Fluid Dynamics. Algorithms were developed for actuator control, synchronization with the native left ventricle (LV), suction detection, and adaptive physiologic control. They were tested in a mock circulation loop (MCL) with INTERMACS 1-2, 3-4, and 5-6 heart failure (HF) profiles using LV pressure-volume loops to examine performance. The algorithms were then tested in chronic implants in healthy sheep for up to 3 months, and in acute implants in sheep with induced HF (ejection fraction < 40%). Results: During MCL tests, in synchronous pulsation (SynchPuls) mode, the membrane pump generated a more physiologic PV loop, with lower mean left atrial pressures (LAP), increased native LV stroke volume, and 1:1 opening of the aortic valve. CF pumps generated a characteristic, non-physiologic narrow PV loop with elevated mean LAP and aortic valve opening once per 3-5 beats. These results demonstrated the SynchPuls algorithm could respond to changes in pre-load to better unload the LV, restore more physiologic hemodynamics, and ensure aortic valve opening, so we proceeded to animal trials, which present more dynamic and challenging conditions. During acute implants in sheep with HF, using SynchPuls, the membrane pump increased cardiac output from ~2 to ~4 LPM. The physiologic control algorithm adjusted pump output to prevent LV suction and retrograde flow during hemodynamic manipulations, including epinephrine administration, and head up or down tilt. The algorithms switched to continuous mode, as intended, when arrhythmias or tachycardia were detected. In chronic implants, the SynchPuls algorithm successfully synchronized with the LV for > 97% of heartbeats and adapted to circadian cycles. Biomarkers of end-organ function returned to baseline within 2 weeks of implant, hemolysis was < 20 mg/dL, and VWF activity was preserved during the chronic implants. Conclusion: These studies showed that the membrane pump can provide physiologic pulsatility and restore cardiac output in HF models. The algorithms’ robustness was confirmed in chronic implants. Overall, these successful tests demonstrated that the CorWave membrane pump can deliver the hemocompatibility, pulsatility, and adaptability required to advance the LVAD field.

Pericardial adiposity is independently linked to adverse cardiovascular phenotypes: a CMR study of 42 598 UK Biobank participants.

AimsWe evaluated independent associations of cardiovascular magnetic resonance (CMR)-measured pericardial adipose tissue (PAT) with cardiovascular structure and function and considered underlying mechanism in 42 598 UK Biobank participants.Methods and resultsWe extracted PAT and selected CMR metrics using automated pipelines. We estimated associations of PAT with each CMR metric using linear regression adjusting for age, sex, ethnicity, deprivation, smoking, exercise, processed food intake, body mass index, diabetes, hypertension, height cholesterol, waist-to-hip ratio, impedance fat measures, and magnetic resonance imaging abdominal visceral adiposity measures. Higher PAT was independently associated with unhealthy left ventricular (LV) structure (greater wall thickness, higher LV mass, more concentric pattern of LV hypertrophy), poorer LV function (lower LV global function index, lower LV stroke volume), lower left atrial ejection fraction, and lower aortic distensibility. We used multiple mediation analysis to examine the potential mediating effect of cardiometabolic diseases and blood biomarkers (lipid profile, glycaemic control, inflammation) in the PAT-CMR relationships. Higher PAT was associated with cardiometabolic disease (hypertension, diabetes, high cholesterol), adverse serum lipids, poorer glycaemic control, and greater systemic inflammation. We identified potential mediation pathways via hypertension, adverse lipids, and inflammation markers, which overall only partially explained the PAT-CMR relationships.ConclusionWe demonstrate association of PAT with unhealthy cardiovascular structure and function, independent of baseline comorbidities, vascular risk factors, inflammatory markers, and multiple non-invasive and imaging measures of obesity. Our findings support an independent role of PAT in adversely impacting cardiovascular health and highlight CMR-measured PAT as a potential novel imaging biomarker of cardiovascular risk.

Effect of food intake on echocardiographic measurements in healthy elderly

This study evaluates whether food intake affects systolic and diastolic echocardiographic measurements in healthy seniors. Thirty healthy subjects 65-70 years of age were investigated with echocardiography, at fasting and then 30, 90, and 180 min after a meal. After 30 min the biggest changes were seen in left ventricular wall stress and myocardial performance index with a decrease of 45% and 33%, respectively, compared to fasting values. Significant (p<.05) increases also were seen in left ventricular stroke volume, left ventricular cardiac output, left ventricular cardiac index, left ventricular outflow velocity-time integral, peak of early diastolic (E) and late diastolic (A) mitral flow velocities, the E/A ratio, pulsed tissue Doppler peak systolic (s') and early (e') and late (a') diastolic velocities, pulmonary vein peak velocities in systole (S) and diastole (D), mitral annular plane systolic excursion (MAPSE), tricuspid annular plane systolic excursion (TAPSE), and global longitudinal strain (GLS) (increases ranging 6%-19%). After 90 min there remained a decrease in wall stress and myocardial performance index of 31% and 17%, respectively, and smaller, but still significant, changes could be seen in left ventricular stroke volume, left ventricular outflow velocity-time integral, MAPSE (lateral), TAPSE, GLS, and a few pulsed tissue Doppler peak systolic velocities and late diastolic velocities. An increase also could be seen in deceleration time of E-wave (DT). After 180 min, all variables except DT were back at baseline or below. No significant changes were seen in S/D ratio, lateral early diastolic velocity (e' lateral) and E/e'ratio. This study shows that food intake affects commonly used echocardiographic parameters, both systolic and diastolic, in healthy seniors. With a few exceptions, the changes seen in the older population were less pronounced than previous studies in younger subjects.

P424 SMALL HEART AND SINGLE CORONARY ARTERY IN A YOUNG PATIENT WITH CHRONIC FATIGUE SYNDROME: A CASE REPORT

Abstract Introduction Chronic fatigue syndrome/Myalgic encephalomyelitis (CFS/ME) is a clinically defined condition reported mostly in adults, characterized by severe and disabling fatigue limiting normal daily activities for at least 6 months accompanied by multiple unexplained symptoms including self–reported impairments in concentration and short–term memory, sleep disturbances, and musculoskeletal pain. Although rarely considered to have cardiac dysfunction, CFS/ME patients frequently have reduced stroke volume with a significant inverse relation between cardiac output and post–exertional malaise severity. We describe a case of a young man affected by CFS/ME and small heart with incidental findings of anomalous origin of the left main coronary artery (LMCA). Case Presentation A 19–year–old Caucasian male presented to our clinic complaining weakness, lack of concentration and excessive daytime sleepiness. Medical history included CFS/ME, D hypovitaminosis, inflammatory bowel disease associated with pancreatic insufficiency. Physical examination including cardiovascular auscultation was unremarkable, with normal blood pressure and heart rate. Electrocardiogram showed sinus rhythm at 75 bpm without any repolarization abnormalities. Echocardiogram revealed reduced diameters of left ventricle (LV) (end–diastolic diameter 36 mm), normal aortic root dimensions and, in a five–chamber apical view, a binary structure that seemed to cross the aorta perpendicularly to its long axis. Cardiac magnetic resonance (CMR) found significantly reduced LV stroke volume (34 ml/m2; normal values 44–68 ml/m2) and end–diastolic volume (57 ml/m2; normal values 68–103 ml/m2) together with reduced end–diastolic wall mass (51 g/m2; normal values 59–93 g/m2). Also, right ventricle (RV) volumes were reduced: stroke volume (32 ml/m2; normal values 40–72 ml/m2), end–diastolic volume (62 ml/m2; normal values 68–114 ml/m2). In addition, the exam confirmed the anomalous origin of LMCA stemming from the proximal segment of right coronary artery and following a retro–aortic course. Conclusions Not sufficient consideration was given to cardiovascular involvement in patients with CFS/ME, although many of signs and symptoms are suggestive of cardiovascular dysfunction. This case highlights that CFS/ME together with small heart is a condition possible also in young people. More studies and reports could be necessary to better define the association with cardiac congenital anomalies and CFS/ME.

How native T1 and T2 mapping is influenced by sex and training load? Cardiac magnetic resonance imaging in young elite athletes and less active individuals

Abstract Funding Acknowledgements Type of funding sources: Other. Main funding source(s): This study was financed by the Ministry of Innovation and Technology NRDI Office within the framework of the Artificial Intelligence National Laboratory Program. LS is supported by the EACVI Research Grant 2021. Introduction Cardiac adaptation due to regular and intense exercise is a well-known phenomenon. Cardiac magnetic resonance (CMR) imaging is a well suited, highly reproducible technique that has a vital role in differentiating physiological adaptation and pathological alterations. Native T1 and T2 mapping enable the quantitative assessment of tissue characteristics without the administration of contrast material. These techniques are increasingly used in studies aiming to consider subtle differences. However, the sex-and training-dependence of native T1 and T2 mapping values remains incompletely understood. Purpose We aimed to describe the differences in native T1 and T2 mapping among healthy athletes and less active individuals. Methods We enrolled healthy elite athletes (n=88, 56 male, 25±5 years) and healthy volunteers (n=82, 46 male, 25±3 years) to undergo CMR examinations at our Centre. Healthy elite athletes performed high sports activity levels (&amp;gt;10 hours/week) and competed nationally or internationally. Sex- and age-matched healthy volunteers engaged in ≤6 hours/week of sports activity. Standardized CMR protocol included short- and long-axis cine images covering the entire left (LV) and right (RV) ventricle and native T1 and T2 mapping in basal, midventricular and apical slices. Results Athletes had consistently higher LV and RV volumes and mass indexes compared to healthy volunteers (p&amp;lt;.001 for all). Native T1 mapping was lower in athletes than in the control group (T1: 954±24 ms vs 970±23 ms; p &amp;lt;.001). T1 mapping showed a moderately strong negative correlation to markers of cardiac adaptation, including LV mass, end-diastolic volume and stroke volume indexes (p&amp;lt;.001 for all). Moreover, we found a negative correlation between native T1 and training hours (Rho: -0.302; p&amp;lt;.001). On the other hand, native T2 mapping showed no difference between athletes and less active controls. Furthermore, T2 correlated with LV shape features but not with training hours. We found that mapping values differed between sexes, both in the athletic and control groups. Females showed slightly higher values compared to their male counterparts (T2: 46±2 vs 43±2; p&amp;lt;.001). Finally, native T1 mapping was associated with training hours and sex in our multiple linear regression model, adjusted for age, resting heart rate, body mass index, body surface area and LVM (p&amp;lt;.001). While T2 mapping was associated only with sex considering the same covariates. Conclusion Our study demonstrates the importance of sex-matched controls in CMR studies evaluating mapping parameters. Moreover, the consideration of exercise load seems paramount in the case of T1 mapping.

Grading mitral regurgitation using 4D flow CMR: Comparison to transthoracic echocardiography.

To determine the 4D Flow Cardiac Magnetic Resonance (CMR) thresholds that achieve the best agreement with transthoracic echocardiography (TTE) for grading mitral regurgitation (MR). We conducted a single-center prospective study of patients evaluated for chronic primary MR in 2016-2020. MR was evaluated blindly by TTE and 4D Flow CMR, respectively by two cardiologists and two radiologists with decades of experience. MR was graded with both methods as mild, moderate, or severe. 4D Flow CMR measurements included MR regurgitant volume per beat (RV) and mitral anterograde flow per beat (MF). RF was obtained as the ratio RV/MF. Additionally, MF was compared to left ventricular stroke volume (LVSV) by cine-CMR. We included 33 patients in the initial cohort and 33 in the validation cohort. Inter-observer agreement was excellent for 4D Flow CMR ICC = .94 (95% CI, .86-.97, p<0.0001). Using recommended TTE thresholds (30 ml, 60 ml, 30%, 50%), agreement was moderate for RV and RF. The best agreement between 4D Flow CMR and TTE was obtained with CMR thresholds of 20 and 40 ml for RV (κ = .93; 95% CI, .8-1) and 20% and 37% for RF (κ = .90; 95% CI, .7-.9). In the validation cohort, agreement between TTE and 4D Flow CMR was good with the optimal thresholds (κ = .78; 95% CI, .61-.94). We propose CMR thresholds that provide a good agreement between TTE and CMR for grading MR. Further studies are needed to fully validate 4D-Flow CMR accuracy for primary MR quantification.