Peak Left Ventricular Twist Research Articles

Left ventricular myocardial work predicts clinical course in patients with heart failure with mildly reduced ejection fraction

Abstract Heart failure with mildly reduced ejection fraction (HFmrEF) often represents a movable patients subset that changes its HF category by increasing or reducing EF. Course prediction is challenging due to insufficient evidence to date. We studied multiple newly established parameters in order to find predictors of clinical course of HFmrEF. Methods 135 patients (61 women) 62±5 years with HFmrEF NYHA II-III on GDMT were enrolled. Longitudinal (GLS), circumferential (GCS) and radial strain (GRS), peak LV twist (LVTR) were measured by speckle tracking from apical and short axis views. Left ventricular (LV) global myocardial work (GW) index (GWI) was obtained from pressure-strain loops derived from LV GLS and supine systemic blood pressure measured right before the image acquisition. Then constructive GW (GCW) as the sum of positive work due to myocardial shortening during systole and negative work due to lengthening during isovolumic relaxation, wasted GW (GWW) as energy loss by myocardial lengthening in systole and shortening in isovolumic relaxation and GW efficiency (GWE) as the percentage ratio of constructive work to the sum of constructive work and wasted work were obtained by dedicated software. All parameters were analyzed offline by one experienced specialist. Patients were followed up for 1 year. Results 38 (28%) patients improved EF to the value ≥50%, 31 (23%) reduced EF to ≤40%. Patients with improved EF had significantly higher absolute values of GLS (17.3±2.2 vs 15.8±3.1%, p<0.03), GCS (18.9±2.6 vs 16.1±1.9%, p<0.02), GRS (42.5±7.2% vs 31.3±4.7%, p<0.02), LVT (6.2±2.5° vs 5.3±2.3°, p<0.03), GCW (2253±121 vs 1872±132 mmHg%, p<0.001) and lower GWW (108±7 vs 128±12 mmHg%) compared with patients with later reduced EF. Multivariate analysis showed that lower GCW was associated with EF reduction (HR 0.982, 95% CI 0.969–0.996, p = 0.012). GCW was the powerful predictor of CV events (AUC 0.94) with cut off value of 1495 mmHg% that had 98% sensitivity and 86% specificity. Conclusion LV GCW predicts EF changes in patients with HFmrEF.

A Characterization of the Cardiac Physiology and Aortic Pulse Wave Properties of Artistic Swimmers Across Competitive Levels.

The distinct physical and environmental stressors of artistic swimming (previously termed synchronized swimming) result in unique hemodynamic stimuli. Given that the hemodynamic stress associated with participation in an exercise modality drives adaptation of the heart and central vasculature, artistic swimming may produce a distinct cardiovascular phenotype. Presumably, athletes competing at the highest levels also have greater training exposure and, thus, exhibit more adaptation. The purpose of this study was to characterize cardiovascular form and function across the competitive spectrum of artistic swimmers. Cardiovascular structure and function were compared in a cross-sectional study of healthy controls, varsity, and elite artistic swimmers, using pulse wave analysis, pulse wave velocity, and echocardiographic images both at rest and during isometric handgrip exercise. Aortic stiffness was similar across all groups, as were characteristics of the decomposed aortic pressure waveform. At rest, both varsity and elite swimmers demonstrated similar systolic function compared to controls. However, peak left ventricular twist was greater in varsity and elites (controls: 8.0 ± 3.9, varsity: 12.8 ± 8.6, elites: 13.4 ± 3.9; both p < 0.02). Furthermore, elites demonstrated greater peak left ventricular radial strain (controls: 29.2 ± 9.9, varsity: 32.5 ± 10.3, elites: 53.9 ± 15.1; both p < 0.001) and longitudinal strain (controls: -16.9 ± 1.6, varsity: -16.5 ± 1.8, elites: -19.5 ± 3.2; both p < 0.04). In contrast to controls, both varsity and elite artistic swimmers demonstrated no change in peak late diastolic transmitral filling velocity (controls: Δ0.2 ± 0.04 m/s, varsity: Δ0.06 ± 0.04 m/s, elites: Δ0.05 ± 0.04 m/s) during isometric handgrip exercise (both p > 0.05), with elites demonstrating lower peak velocity than varsity swimmers, (p = 0.048) indicating preservation of diastolic function. Artistic swimmers demonstrate distinct cardiac physiology at rest and during isometric handgrip, with a greater extent of distinguishing features observed in those competing at the highest level of competition.

Exaggerated myocardial torsion may contribute to dynamic left ventricular outflow tract obstruction in hypertrophic cardiomyopathy.

Dynamic left ventricular (LV) outflow tract obstruction (LVOTO) is associated with symptoms and increased risk of developing heart failure in hypertrophic cardiomyopathy (HCM). The association of LVOTO and LV twist mechanics has not been well studied in HCM. The aim of the study was to compare the pattern of LV twist in patients with HCM associated with asymmetrical septal hypertrophy with and without LVOTO. Echocardiography (including speckle tracking) was performed in 212 patients with HCM, divided according to the absence (n = 130) or presence (n = 82) of LVOTO (defined as peak pressure gradient ≥30 mmHg either at rest and/or with Valsalva manoeuvre). Patients with LVOTO were older, had smaller LV dimensions, a higher LV ejection fraction (LVEF), a longer anterior mitral valve leaflet length, and a higher early transmitral pulsed wave to septal tissue Doppler velocity ratio (E/E'). A univariate analysis showed that peak twist was significantly higher in patients with LVOTO compared with patients without LVOTO (19.7 ± 7.3 vs. 15.7 ± 6.0, P = 0.00015). Peak twist was similarly enhanced in patients with LVOTO, manifesting only during Valsalva (19.2 ± 5.6, P = 0.007) and patients with resting LVOTO (19.9 ± 8.0, P = 0.00004) compared with patients without LVOTO (15.7 ± 6.0). A stepwise forward logistic regression analysis showed that LVEF, LV end-systolic dimension indexed to body surface area, anterior mitral valve leaflet length, E/E', and peak twist were all independently associated with LVOTO. This study demonstrates that increased peak LV twist is independently associated with LVOTO in patients with HCM. Peak twist was similarly exaggerated in patients with only latent LVOTO, suggesting that it may play a contributory role to LVOTO in HCM.

Influence of chest conformation on myocardial strain parameters in healthy subjects with mitral valve prolapse.

Chest shape might affect myocardial strain parameters. However, the relationship between myocardial strain parameters and chest conformation has not been previously investigated in subjects with mitral valve prolapse (MVP). Between April 2019 and May 2020, 60 healthy subjects (50.1 ± 8.6year/old, 46.6% females) with MVP and mild-to-moderate mitral regurgitation, and 60 controls matched by age, sex, and cardiovascular risk factors were consecutively studied. Participants underwent modified Haller index (MHI) assessment (ratio of chest transverse diameter over the distance between sternum and spine), and transthoracic echocardiography implemented with 2D-speckle tracking analysis. MHI was significantly greater in MVP group than controls (2.6 ± 0.35 vs 2.1 ± 0.23, p < 0.0001). Left ventricular (LV) ejection fraction was similar in MVP and controls (63.5 ± 3.7% vs 64.3 ± 3.9%, p = 0.25). LV regional and global longitudinal (GLS), circumferential (GCS) and radial strain (GRS) parameters and LV peak twist were all significantly lower in MVP compared to controls (all p < 0.0001). MVP subjects with a tight chest (MHI > 2.5, n = 30), and those with MHI ≤ 2.5 (n = 30) were then separately analyzed. A significant impairment in myocardial strain parameters and LV peak twist was documented in MVP subjects with MHI > 2.5, but not in those with MHI ≤ 2.5. MHI showed a strong inverse correlation with LV-GLS (r = - 0.85), GCS (r = - 0.84), GRS (r = - 0.84) and LV peak twist (r = - 0.94). In MVP subjects, impairment of myocardial strain parameters is not due to intrinsic reduction of cardiac contractility function, but it appears to be related to the degree of chest deformity.

Differences In Left Ventricular Twist In Elite Short And Long Distance Swimmers

Exercise-induced cardiac remodeling is influenced by sport-specific exercise characteristics, such as the isometric and isotonic components of the activity. Differences in cardiac dimensions and left ventricular (LV) systolic and diastolic function have been observed between short- (SS) and long-distance (LS) swimmers. Intensity and duration specific adaptations in LV mechanics may help to explain these differences in global function. PURPOSE: To examine whether there are event-specific differences in LV twisting mechanics between elite SS and LS athletes. METHODS: Data were collected during the 2019 FINA World Championships. SS were identified as competing in pool events ranging from 50-400m; LS were identified as open water swimmers competing in events 5-25 km. Fourteen SS (7 males; 23±4 years; 100% identified as white) and 14 sex, age and ethnicity matched LS were selected for comparison. Echocardiography was performed in the left lateral decubitus position following 10 minutes of rest. Parasternal short axis images at the level of the mitral valve and apex were analyzed using speckle-tracking software and post-processed in custom software to normalize the temporal sequence of heart rate. RESULTS: Data are presented as mean ± SD for LS vs. SS. Athletes had a similar body surface area (1.92 ± 0.15 vs. 1.94 ± 0.18 m2, P=0.76), resting heart rate (52 ± 10 vs. 54 ± 8 bpm, P=0.54), years of event-specific training (11 ± 6 vs. 14 ± 5 years, P=0.21), and weekly training duration (25 ± 5 vs. 22 ± 5 hours/week, P=0.15). Peak LV twist (13.8 ± 3.5 vs. 12.7 ± 5.0 deg, P=0.49) and peak LV twist normalized to LV length (1.7 ± 0.5 vs. 1.6 ± 0.6 deg/cm, P=0.67) were similar between groups. Time to peak LV twist (94 ± 4 vs. 98 ± 4 % systole, P=0.006) and time to peak LV untwisting rate (9 ± 4 vs. 12 ± 3 % diastole, P=0.03), were faster in LS, while time to peak twisting rate was also trending to be faster in LS (56 ± 9 vs. 62 ± 10 % systole, P=0.06). CONCLUSION: In swimming, event distance appears to influence the temporal sequence of LV mechanics at rest with faster twisting and untwisting rates occurring in swimmers who train and compete in longer-distances. The relationship between these observations and global systolic and diastolic function warrants investigation.

Superior cardiac mechanics without structural adaptations in pre-adolescent soccer players.

This study aimed to evaluate left ventricular structure, function and mechanics, in highly-trained, pre-adolescent soccer players compared with age- and sex-matched controls. The study design was a prospective, cross-sectional comparison of left ventricular structure, function and mechanics. Twenty-two male soccer players from two professional youth soccer academies (age: 12.0 ± 0.3 years) and 22 recreationally active controls (age: 11.7 ± 0.3 years) were recruited. Two-dimensional conventional and speckle tracking echocardiography were used to quantify left ventricular structure, function and peak/temporal values for left ventricular strain and twist, respectively. End-diastolic volume index was larger in soccer players (51 ± 8 mm/(m2)1.5vs. 45 ± 6 mm/(m2)1.5; p = 0.007) and concentricity was lower in soccer players (4.3 ± 0.7 g/(mL)0.667vs. 4.9 ± 1.0 g/(mL)0.667; p = 0.017), without differences in mean wall thickness between groups (6.0 ± 0.4 mm vs. 6.1 ± 0.5 mm; p = 0.754). Peak circumferential strain at the base (-22.2% ± 2.5% vs. -20.5% ± 2.5%; p = 0.029) and papillary muscle levels (-20.1% ± 1.5% vs. -18.3% ± 2.5%; p = 0.007) were greater in soccer players. Peak left ventricular twist was larger in soccer players (16.92° ± 7.55° vs. 12.34° ± 4.99°; p = 0.035) and longitudinal early diastolic strain rate was greater in soccer players (2.22 ± 0.40 s-1vs. 2.02 ± 0.46 s-1; p = 0.025). Highly-trained soccer players demonstrated augmented cardiac mechanics with greater circumferential strains, twist and faster diastolic lengthening in the absence of differences in wall thickness between soccer players and controls.

Left ventricular myocardial deformation abnormalities in seizure-free children with epilepsy

PurposeAlthough there is a higher risk of structural cardiac disease in people with epilepsy, there is no detailed advanced analysis of cardiac functions in patients with epilepsy. This study aimed to determine early echocardiographic findings of Left Ventricular (LV) dysfunction using cardiac strain technique in seizure-free children with epilepsy. MethodThe study investigated 60 children with epilepsy who had no seizures in the preceding 6 months, without any known cardiovascular disease and treated with one antiepileptic drug and 60 healthy subjects who underwent clinical evaluation including electrocardiography (ECG), standard echocardiography, tissue Doppler imaging (TDI) and two-dimensional Speckle Tracking Echocardiography (2DSTE). ResultsDespite the normal M-mode values, global longitudinal strain of the epilepsy of the control group was as follows: −16.86 ± 3.71, -18.95 ± 3.75, respectively (p = 0.001); global strain rates were determined as follows: -0.99 ± 0.23, -1.14 ± 0.31, respectively (p = 0003). The patients also had increased A-wave velocity, and decreased E/A ratio (p < 0.01). TDI results showed diastolic dysfunction as mirrored by significantly increased isovolemic relaxation time (IVRT), Early mitral inflow (E)/ Early diastolic velocity (E’), and Tei index (p < 0.01). There was no significant difference in LV torsion, Peak LV twist, and ECG parameters between the patients and the controls. ConclusionsIn seizure-free patients, cardiac systolic and diastolic functions were impaired when compared to healthy children. There was no difference in the patient group to explain the decline in cardiac functions and there may be unknown different factors besides the known risk factors.

Blood pressure is normal, but is the heart?

There is no detailed strain analysis of cardiac functions in treated hypertensive pediatric patients. The aim of this study was to evaluate the cardio-protective effects of different drug classes in treated pediatric hypertensive patients. Sixty non-obese-treated hypertensive patients with preserved left ventricular (LV) systolic function and 45 age-, sex-, and body mass index-matched healthy subjects underwent clinical evaluation, including 24-h ambulatory blood pressure monitoring, standard echocardiographic examination, tissue Doppler imaging, and two-dimensional Speckle Tracking Echocardiography. The patients were divided into two subgroups based on the effects of the drugs on the Renin Angiotensin Aldosterone System. The subgroup hypertension (HT) 1 received angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, and HT 2 subgroup received calcium channel blocker, β-blocker, or diuretics. There was no difference between the two groups and subgroups with respect to clinical, demographic, ABPM, ventricular volumes, ejection fraction, and tissue Doppler imaging (TDI) parameters. For patients and controls, respectively, global longitudinal strain was - 18.70 ± 3.41 versus - 21.01 ± 3.82 (P < 0.001), and global radial strain was 40.6 ± 9.8 versus 54.8 ± 12.8 (P = 0.004). Peak LV twist and peak LV torsion were not significantly different. The patient subgroup analyses with each other revealed no difference in systolic and diastolic myocardial deformation properties. Strain parameters were reduced in all treated hypertensive children compared to normotensive children, and the various cardiac mechanic parameters were similarly abnormal no matter what type of antihypertensive agent was used.

OS 23-06 CAN LEFT VENTRICULAR TORSIONAL MECHANICS USING SPECKLE TRACKING ECHOCARDIOGRAPHY IN PREGNANCY TO PREDICT THE NEW ONSET HEART FAILURE?

Objective: Normal pregnancy is associated with reversible changes in both systolic and diastolic mechanics, consistent with an increase in preload and decrease in afterload and systemic vascular resistance. The aim is to evaluate left ventricular (LV) twist and untwist mechanics in a population of pregnant women during differing stages of a healthy pregnancy. Design and Method: We included 22 pregnant patients, 10 with multiple pregnancy (mean age 36.5 ± 3 years) and 20 healthy non pregnant women (mean age 33 ± 4years). Apical and basal short axis for 2D images were acquired (frame rate 65 ± 7 frames/s) and images will be obtained during the first, second, and third trimester, as well as up to two months postpartum. Results: Peak LV twist and untwisting rate increased significantly in the 3rd trimester of normal pregnancy (13.48 ± 2.90°, 13.12 ± 3.30°, 16.83 ± 3.61°, P < 0.001; and −111.52 ± 23.54°/sec, −107.40 ± 26.58°/sec, −144.30 ± 45.14°/sec, P < 0.001; in the 1st, 2nd, and 3rd trimester, respectively). The pregnants with twins have the higher value for LVT and LVUR compare p < 0.01), but in the last trimester, the time to peak LVUR is prolonged. An independent association was found between the change in LV twist and LV end-systolic volume between the 1st and 3rd trimester. Peak untwisting rate at the 3rd trimester correlated significantly with peak twist and LV end-diastolic volume. Multiple regression analysis indicates that only systolic blood pressure (r = 0.394, P = 0.005) was an independent predictor for increased LV torsion. Conclusions: LV twist and peak untwisting rate increase in the 3rd trimester and correlate with end-systolic and end-diastolic volume, respectively. Blood pressure and condition of multiple pregnancy are independently associated with increased torsion during pregnancy and may predict the new onset heart failure and perinatal cardiomyopathy.

Effect of free-breathing on left ventricular rotational mechanics in healthy subjects and patients with duchenne muscular dystrophy.

Cardiovascular magnetic resonance imaging exams can be performed during free-breathing. This may be especially important for boys with Duchenne muscular dystrophy (DMD) given their frequently limited breath-hold abilities. The impact of the respiratory compensation method on quantitative measurements of left ventricular (LV) rotational mechanics is incompletely understood. The purpose of this study was to evaluate differences in LV rotational mechanics acquired during breath-holding (BH), free-breathing with averaging (AVG), and free-breathing with respiratory bellows gating (BEL). LV short-axis tagged images from healthy subjects (N = 16) and DMD patients (N = 5) were acquired with BH, AVG, and BEL. LV twist and circumferential-longitudinal shear (CL-shear) angle were measured using the Fourier Analysis of STimulated echoes (FAST) method. Peak LV twist estimates using BEL were significantly lower compared with BH in both healthy subjects (10.2 ± 3.6 ° versus 12.9 ± 2.3 °, P = 0.003) and patients with DMD (8.6 ± 3.6 ° versus 10.5 ± 3.6 °, P = 0.004). AVG results were in between BEL and BH. No significant differences in CL-shear were detected between BEL and BH. Breath-holding directly affects estimates of peak LV twist, but not CL-shear. Using a free-breathing strategy for the evaluation of cardiac function is important for intrasubject longitudinal studies, intersubject comparisons, and multicenter trials for patients with DMD. Magn Reson Med 77:864-869, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

Mechanical effects of left ventricular midwall fibrosis in non-ischemic cardiomyopathy.

BackgroundLeft ventricular (LV) mid-wall fibrosis (MWF), which occurs in about a quarter of patients with non-ischemic cardiomyopathy (NICM), is associated with high risk of pump failure. The mid LV wall is the site of circumferential myocardial fibers. We sought to determine the effect of MWF on LV myocardial mechanics.MethodsPatients with NICM (n = 116; age: 62.8 ± 13.2 years; 67 % male) underwent late gadolinium enhancement cardiovascular magnetic resonance (CMR) and were categorized according to the presence (+) or absence (−) of MWF. Feature tracking (FT) CMR was used to assess myocardial deformation.ResultsDespite a similar LVEF (24.3 vs 27.5 %, p = 0.20), patients with MWF (32 [24 %]) had lower global circumferential strain (Ɛcc: −6.6 % vs −9.4 %, P = 0.004), but similar longitudinal (Ɛll: −7.6 % vs. −9.4 %, p = 0.053) and radial (Ɛrr: 14.6 % vs. 17.8 % p = 0.18) strain. Compared with − MWF, + MWF was associated with reduced LV systolic, circumferential strain rate (−0.38 ± 0.1 vs −0.56 ± 0.3 s−1, p = 0.005) and peak LV twist (4.65 vs. 6.31°, p = 0.004), as well as rigid LV body rotation (64 % vs 28 %, P <0.001). In addition, +MWF was associated with reduced LV diastolic strain rates (DSRcc: 0.34 vs. 0.46 s−1; DSRll: 0.38 vs. 0.50s−1; DSRrr: −0.55 vs. −0.75 s−1; all p <0.05).ConclusionsMWF is associated with reduced LV global circumferential strain, strain rate and torsion. In addition, MWF is associated with rigid LV body rotation and reduced diastolic strain rates. These systolic and diastolic disturbances may be related to the increased risk of pump failure observed in patients with NICM and MWF.

Left ventricular shape and mass impact torsional dynamics in asymptomatic patients with chronic aortic regurgitation and normal left ventricular ejection fraction.

Chronic aortic regurgitation (AR) is associated with a unique pattern of left ventricular (LV) volume and pressure overload, leading to LV remodelling. LV torsional motion, a key component of LV performance, can be altered in this setting. We aimed to assess the impact of LV remodelling on LV torsional dynamics parameters using speckle-tracking echocardiography (STE) in asymptomatic AR patients. We prospectively enrolled 60 patients with chronic AR and LVEF > 50% and 55 healthy controls. LV rotation, twisting and untwisting were assessed using STE. Patients with AR had higher LV diameters, volumes and mass, a more spherical LV shape than controls, but similar LVEF. In AR patients we found reduced peak LV apical rotation and decreased (2.1 ± 0.8 vs 2.9 ± 0.9°/cm, p < 0.001) and delayed (time to peak LV twist: 0.94 ± 0.12 vs 0.99 ± 0.09, p = 0.004) peak LV torsion. Also, peak LV untwisting velocity was decreased (-123.5 ± 41.5 vs -152.3 ± 55.0°/s, p = 0.002) due to lower peak LV apical diastolic rotation rate. LV shape influenced LV torsional dynamics, a more spherical LV displaying reduced peak LV apical rotation and diastolic rotation rate and decreased LV twist. A more hypertrophied LV had a lower peak LV torsion, peak LV apical diastolic rotation rate and peak LV untwisting velocity. LV apical rotation and torsion are decreased and LV twist is delayed in patients with chronic AR and normal LVEF, detecting early subclinical LV dysfunction before LVEF declines. Also, LV untwisting is reduced in these patients. LV remodelling impairs LV torsional dynamics parameters in this setting.

Four-Dimensional Speckle Tracking Echocardiography in Patients with Hypertrophic Cardiomyopathy.

Abnormal left ventricular (LV) deformational mechanics have been demonstrated in patients with hypertrophic cardiomyopathy (HCM) using two-dimensional (2D) speckle tracking echocardiography, but there is not enough information about the four-dimensional speckle tracking echocardiography (4DSTE) in these patients. The objective of the study was to identify and quantify the left ventricular contractility in patients with HCM using 4DSTE. Thirty patients [age, 54.6 ± 12.1 years; 12 (40%) women] with diagnosis of nonobstructive HCM and 20 healthy controls [age, 47.42 ± 11.43 years; 8 (40%) women] underwent 4DSTE measurement of longitudinal, radial, circumferential, and area strains. Patients with HCM showed lower longitudinal (-13.5% vs. -20.3%, P < 0.001) and radial (33.4% vs. 43.6%, P < 0.001) strain, but higher circumferential (-22.7% vs. -15.9%, P < 0.001) and area (-30.7% vs. -22.1%, P < 0.001) strain than control subjects. Peak LV twist showed significantly higher values in patients with HCM (13.7 ± 5.3 vs. 11.3 ± 4.8, P < 0.005). Patients with HCM have reduced longitudinal and radial strain but increased circumferential and area strain on 4DSTE. These results are found appropriate with previous 2DSTE studies. Thus, 4DSTE is useful to determine LV deformational mechanics.

Association of Mitral Annular Calcification with Left Ventricular Mechanics: A Speckle Tracking Study.

Mitral annular calcification (MAC) is a common echocardiographic finding in clinical practice and is associated with cardiovascular risk factors and atherosclerosis. However, data regarding left ventricular (LV) functions are lacking. We aimed to evaluate the relationship between MAC and LV mechanical functions with the utility of two-dimensional speckle tracking echocardiography (2DSTE). The study involved 91 patients with MAC and 48 control subjects. Mitral annular thickness of 1-2 mm was reported as mild, 2-5 mm as moderate, and >5 mm as severe MAC. All patients underwent 2D echocardiography. MAC was observed in 91 (65.5%) patients. Of LV diastolic parameters, E/Em ratio, LAVI, LV mass index, and t-LV UR were increased. Of LV systolic parameters, GLS and Sm were decreased, whereas Ar, Ar-rate systole, peak LV twist, peak LV twist rate, LV-tor, and MPI were increased, which were all correlated with presence and severity of MAC. Multivariate linear regression analysis showed that LV mass index (β = 0.225, P = 0.012), t-LV UR (β = 0.370, P < 0.001), LV mass index (β = 0.183, P = 0.025), MPI (β = 0.288, P < 0.001), and GLS (β = -0.385, P < 0.001) were significantly associated with MAC severity. The presence and severity of MAC is associated with impaired LV systolic and diastolic functions. Therefore, preventive strategies might be taken in patients with MAC to avoid LV systolic and diastolic dysfunction.

Effects of non-dipper blood pressure pattern on left ventricular rotational mechanics in hypertensive patients with type 2 diabetes mellitus: a speckle tracking study

We aimed to evaluate the effects of non-dipper BP pattern on left ventricular (LV) rotational mechanics in hypertensive patients with type 2 diabetes mellitus (T2DM) with the utility of two-dimensional speckle tracking echocardiography (2D-STE). Eighty-six hypertensive patients with T2DM were enrolled. All patients underwent 2D-echocardiography and 24-h-ambulatory blood pressure monitoring. Fifty-nine (59.3%) patients had non-dipper BP pattern and all subjects had normal LV function. Patients with non-dipper BP pattern had decreased systolic tissue velocity (p: 0.006), increased peak systolic apical rotation and rotation rate (p: 0.008 and p: 0.014, respectively), and peak LV twist and twist rate (p: 0.005 and p: 0.012, respectively). Analysis of LV diastolic parameters showed that, early diastolic tissue velocity (Em) was decreased and E/Em ratio and LV mass (LVM) index were increased in non-dipper group while the time to LV untwisting rate was delayed. In multivariate analysis, peak LV twist (β = 0.459, p: < 0.001) and twist rate (β = 0.388, p: 0.001) were independently associated with the difference between mean arterial pressure (MAP)-asleep and MAP-awake. In correlation analysis adjusted for age, sex and LVM index, the time to LV untwisting rate was positively correlated with the difference between MAP-asleep and MAP-awake (r: 0.290 vs. p: 0.008) and E/Em ratio (r: 0.280 vs. p: 0.010). LV rotational mechanics are impaired in T2DM non-dipper hypertensive patients, indicating LV systolic and diastolic dysfunction. 2D-STE may permit better understanding of the underlying pathophysiology and development of preventive strategies.

Factors Influencing the Twisting and Untwisting Properties of the Left Ventricle during Normal Pregnancy

During pregnancy, important hemodynamic changes occur, consistent with an increase in preload and decrease in afterload and systemic vascular resistance. The aim of the present study was to investigate the changes in left ventricular (LV) strain and rotational properties during the 3 trimesters of normal pregnancy and to examine the factors that drive these changes. Twenty-seven pregnant women (29.7 ± 6.9 years) and 11 age-matched nonpregnant controls (29.9 ± 5.4 years) were evaluated. Conventional echocardiography and two-dimensional speckle tracking imaging were performed at 8-12 (1st trimester), 21-28 (2nd trimester), and 33-36 (3rd trimester) weeks of pregnancy. LV rotation, twist, untwisting rate, and circumferential strain were measured using the parasternal short-axis views at basal and apical levels. Global longitudinal strain was calculated from the LV apical views. Peak LV twist and peak untwisting rate increased significantly in the 3rd trimester of normal pregnancy (13.48 ± 2.90°, 13.12 ± 3.30°, 16.83 ± 3.61°, P < 0.001; and -111.52 ± 23.54°/sec, -107.40 ± 26.58°/sec, -144.30 ± 45.14°/sec, P < 0.001; in the 1st, 2nd, and 3rd trimester, respectively). Global longitudinal and circumferential strain of the apex decreased significantly from the 2nd trimester. An independent association was found between the change in LV twist and the change in LV end-systolic volume between the 1st and 3rd trimester. Peak untwisting rate at the 3rd trimester correlated significantly with peak twist and LV end-diastolic volume. During normal pregnancy, LV twist and peak untwisting rate increase in the 3rd trimester and correlate with end-systolic and end-diastolic volume, respectively. Circumferential strain of the apex and global longitudinal strain decrease from the 2nd trimester.

Left ventricular twist angle: echocardiographic assessment of amplitude and timing in normal and disease conditions

Purpose: The current concept of myocardial function incorporates complex rotational mechanics. Speckle Tracking Echocardiography (STE) allows for left ventricular (LV) twist deformation assessment, but quantitative data are often variable and little is known of torsional timing. The aim was to evaluate the LV twist angle and sequence of rotation in severe systolic dysfunction, less pronounced disease and in normal conditions. Methods: 101 subjects were studied (mean age 48.1±15 years, 46% women). Of these, 33 patients (PTS) demonstrated severe LV systolic dysfunction with EF ranging from 14 to 34%, mean 26.7% (Group 3); 33 PTS showed LV EF ranging from 37 to 69%, mean 55.5% (Group 2); and 35 subjects were healthy volunteers with EF between 62 and 67%, mean 65.2% (Group 1). Concurrent net LV twist angle was calculated using two-dimensional STE short axis images as the absolute apex-to-base difference in LV rotation at time of aortic valve closure (AVC). Time to peak apical and basal rotation was also measured as well as AVC independent peak LV twist angle, indicating the maximal torsional deformation without isochronal occurrence. Results: LV twist angle at AVC was significantly lowest in Group 3, showing a mean value of 5.6±5.0° (p<0.001), but no difference was found between Group 1 and 2, with measurements of 13.3±4.7° and 16.1±6.3°, respectively. In general, peak rotation was different from the values measured at AVC and did not occur simultaneously at basal and apical level. Therefore, LV twist angle at AVC was lower than peak twist angle in 96% of subjects. However, both measurements showed good correlation, with coefficients of 0.87, 0.9 and 0.87 in Group 3, 2 and 1, respectively. The absolute difference between time to peak apical and basal rotation was significantly larger in Group 3 as compared to Group 1, showing mean values of 96.8±81.2 ms and 44.3±41.0 ms, respectively (p=0.01). Conclusions: LV twist angle at aortic valve closure shows significant decrease in patients with severe LV systolic dysfunction, but due to a potential compensatory mechanism is comparable between patients with less pronounced disease and healthy subjects. Measurements of LV twist angle at aortic valve closure and at maximal amplitude show good correlation, though there is a temporal gradient of LV peak rotation between basal and apical level. This absolute timing difference is larger in patients with severe LV systolic dysfunction as compared to healthy subjects.

Assessment of Age‐Related Changes in Left Ventricular Twist by 3‐Dimensional Speckle‐Tracking Echocardiography

The purpose of this study was to determine the normal value of left ventricular (LV) twist in 3-dimensional (3D) geometry and to study the effects of aging on 3D LV twist by sophisticated newly developed 3D speckle-tracking echocardiographic techniques. Recent developments in miniaturized ultrasound arrays have provided us with high-quality 3D echocardiographic data. Speckle tracking based on 3D images is robust to out-of-plane motion error, whereas 2-dimensional speckle tracking is inherently unable to analyze 3D cardiac motion and may lead to measurement inaccuracies. Three-dimensional LV volumetric images were acquired from 124 healthy volunteers (aged 21-82 years) and were analyzed by a recent speckle-tracking method. Left ventricular twist was analyzed as apical rotation relative to the base in the 3D coordinates. The measured parameters in this study were peak apical rotation, peak basal rotation, peak LV twist, normalized peak LV twist, and peak untwist velocity. As seen from the apex, the normal LV maintains a wringing systolic displacement with an initial counterclockwise rotation followed by a clockwise rotation in the LV basal plane and a counterclockwise rotation in the LV apical plane. In general, the apical and basal twist increases during the aging process, leading to an increased LV twist value. The mean peak twist ± SD in young participants (21-35 years) was 11.73° ± 2.67°, whereas the value for older participants (>65 years) was 18.57° ± 3.08° (P < .001). Three-dimensional speckle-tracking echocardiography can be an effective noninvasive method for assessing 3D LV twist. Age-related differences in the 3D LV twist may be the result of the age-related changes in the endocardial myofibers.

Effects of age on left ventricular twist-displacement loop assessed by velocity vector imaging

To assess effect of age on the characteristic of left ventricular (LV) twist-displacement loop in health volunteers by velocity vector imaging (VVI) and to provide a new method for LV function evaluation in clinic. After obtaining basal and apical LV short-axis images in 98 healthy volunteers (18-75 years old) by 2-dimensional echocardiography, we use VVI software to analysis LV twist motion and radial displacement at each plane off-line. The peak LV twist (Ptw), the peak untwist velocity (PutwV), the proportion of untwist in isovolumetric relaxation period (Iutw%) and LV radial displacement (Dis) were measured and calculated. Then we constructed LV twist-displacement loop and compared the characteristic of them among different groups. Ptw increased gradually with the increase in age. The biggest PutwV was in the group of 30-60 years old. Iutw% increased gradually before 60 years old, then decreased after that. Dis was not obviously different among the three groups. The characteristic of LV twist-displacement loop was like the configuration of 8. There was a linear relation between twist and displacement during systole, and the slope increased gradually with the increase in age. During early diastole, the relatively small radial expanding displacement displayed with untwisting, resulting in a much steeper twist-displacement relationship curve occurred in each group, which was getting smooth gradually when the radial expanding displacement increased during mid to late diastole. VVI can be used to effectively and noninvasively assess LV twist-displacement loop with change in age and provide important information for LV function. The effect of age must take into account when evaluate the LV function by the twist-displacement loop.

Feasibility and reproducibility of peak left ventricular twist in children with and without heart disease

Feasibility and reproducibility of peak left ventricular twist in children with and without heart disease