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Introduction: 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. Methods: Twenty anaesthetised open-chest pigs were put on cardiopulmonary bypass with aortic cross-clamping and suboptimal cardioplegic arrest for 40 min. After declamping and defibrillation, the animals were supported by VA-ECMO for 180 min either with or without additional left ventricular venting. Continuous haemodynamic evaluations were performed at baseline and at cardiac arrest, during VA-ECMO and for 120 min 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 2 h with unsupported circulation. Results: 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 120 min after weaning from circulatory support, left ventricular stroke work and pressure-volume area were increased in vented compared to not vented animals. At 120 min 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 ± 2.1 J/mL/g, p = 0.011) in vented- compared to not vented hearts. Conclusion: This experimental study demonstrate that left ventricular venting during post-cardiotomy veno-arterial ECMO for 3 h attenuates deterioration of left ventricular function and haemodynamics early after weaning from circulatory support. [ABSTRACT FROM AUTHOR]

Chronic exercise induces adaptive changes of left ventricular (LV) ejection and filling capacities which may be detected by novel speckle‐tracking echocardiography (STE) and tissue Doppler imaging (TDI)‐based techniques. A total of 103 consecutive male elite Norwegian soccer players and 46 age‐matched healthy controls underwent echocardiography at rest. STE was used to assess LV torsional mechanics and LV systolic longitudinal strain (LS). Diastolic function was evaluated by trans‐mitral blood flow, mitral annular velocities by TDI, and LV inflow propagation velocity by color M‐mode. Despite similar global LS, players displayed lower basal wall and higher apical wall LS values vs controls, resulting in an incremental base‐to‐apex gradient of LS. Color M‐mode and TDI‐derived data were similar in both groups. Peak systolic twist rate (TWR) was significantly lower in players (86.4±2.8 vs controls 101.9±5.2 deg/s, P<.01). Diastolic untwisting rate (UTWR) was higher in players (−124.5±4.2 vs −106.9±6.7 deg/s) and peaked earlier during the cardiac cycle (112.7±0.8 vs 117.4±2.4% of systole duration, both P<.05). Untwisting/twisting ratio (−1.48±0.05 vs −1.11±0.08; P<.001) and untwisting performance (=UTR/TW; −9.25±0.34 vs −7.38±0.40 s−1, P<.01) were increased in players. Augmented diastolic wall strain (DWS), a novel measure of LV compliance in players, was associated with improved myocardial mechanical efficiency. The described myocardial biomechanics may underlie augmented exertional cardiac function in athletes and may have a potential role to characterize athlete′s heart by itself or to distinguish it from hypertensive or hypertrophic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Background and Aims: Increased myocardial oxygen (O 2 ) demand carries higher cardiovascular risk in hypertension. We hypothesized that myocardial O 2 demand is increased in severe obesity and linked to early left ventricular (LV) dysfunction., Methods and Results: Baseline data from 106 severely obese subjects referred for gastric bypass surgery (42 ± 11 years, 74% women, body mass index [BMI] 41.9 ± 4.8 kg/m 2 , 32% with hypertension) in the prospective FatWest (Bariatric Surgery on the West Coast of Norway) study was used. LV systolic function was assessed by biplane ejection fraction (EF), midwall shortening (MWS) and endocardial global longitudinal strain (GLS), and LV diastolic function by mitral annular early diastolic velocity (e'). Myocardial O 2 demand was estimated from the LV mass-wall stress-heart rate product (high if > 1.62 × 10 6 /2.29 × 10 6  g kdyne/cm 2 bpm in women/men). High myocardial O 2 demand was found in 33% and associated with higher BMI and high prevalence of low GLS (65%) and low MWS (63%) despite normal EF. In ROC analyses, higher myocardial O 2 demand discriminated between patients with low vs. normal MWS and GLS (area under curve 0.71 and 0.63, p < 0.05). In successive multiple regression analyses, higher myocardial O 2 demand was associated with lower LV MWS, GLS and average e', respectively, independent of age, gender, BMI, pulse pressure, diabetes mellitus, and EF (all p < 0.05)., Conclusion: In obese patients without known heart disease and with normal EF referred for bariatric surgery, high myocardial O 2 demand is associated with lower myocardial function whether assessed by GLS or MWS independent of confounders. CLINICALTRIALS., Gov Identifier: NCT01533142., Competing Interests: Declaration of competing interest The authors have no relationship with industry to disclose., (Copyright © 2020 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.)

Background: Automatic quantification of left ventricular (LV) function could enhance workflow for cardiologists and assist inexperienced clinicians who perform focused cardiac ultrasound. We have developed an algorithm for automatic measurements of the mitral annular plane systolic excursion (MAPSE) and peak velocities in systole (S') and early (e') and late (a') diastole. We aimed to establish normal reference values for the automatic measurements and to compare them with manual measurements., Methods and Results: Healthy participants (n = 1157, 52.5% women) from the HUNT3 cross-sectional population study in Norway were included. The mean age ± standard deviation (SD) was 49 ± 14 (range: 19-89) years. The algorithm measured MAPSE, S', e', and a' from apical 4-chamber color tissue Doppler imaging (cTDI) recordings. The manual measurements were obtained by two echocardiographers, who measured MAPSE by M-mode and the velocities by cTDI. For men and women, age-specific reference values were created for groups (mean ± 1.96SD) and by linear regression (mean, 95% prediction interval). Age was negatively correlated with MAPSE, S', and e' and positively correlated with a'. There were small differences between genders. Normal reference ranges were created. The coefficients of variation between automatic and manual measurements ranged from 5.5% (S') to 11.7% (MAPSE)., Conclusion: Normal reference values for automatic measurements of LV function indices are provided. The automatic measurements were in line with the manual measurements. Implementing automatic measurements and comparison with normal ranges in ultrasound scanners can allow for quick and precise interpretation of LV function., (© 2019 The Authors. Echocardiography published by Wiley Periodicals, Inc.)