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A subgroup of right bundle branch block (RBBB) patients may exhibit a significant left ventricular (LV) activation delay. We evaluated echocardiography in a non-ischemic heart failure patient whose QRS morphology changed from left bundle branch block (LBBB) to atypical RBBB. The septum to posterior wall motion delay (SPWMD) measured using the M-mode was 196 ms while the patient presented with LBBB but decreased to 32 ms after the morphology changed to RBBB. These changes were also associated with delayed appearance of the septal displacement peak. Speckle tracking longitudinal strain was evaluated using three standard apical views after the morphology changed to RBBB. The LV contraction initially appeared in the basal inferior wall and there was delayed anterior wall contraction. The LV contraction pattern in our patient changed when the QRS morphology changed to atypical RBBB. A specific LV contraction sequence observed in atypical RBBB may reflect a significant LV activation delay between the inferior and anterior wall.

Three main mechanisms contribute to global right ventricular (RV) function: longitudinal shortening, radial displacement of the RV free wall (bellows effect), and anteroposterior shortening (as a consequence of left ventricular contraction). Since the importance of these mechanisms may vary in different cardiac conditions, a technology being able to assess their relative influence on the global RV pump function could help to clarify the pathophysiology and the mechanical adaptation of the chamber. Previously, we have introduced our 3D echocardiography (3DE)-based solution—the Right VentrIcular Separate wall motIon quantificatiON (ReVISION) method—for the quantification of the relative contribution of the three aforementioned mechanisms to global RV ejection fraction (EF). Since then, our approach has been applied in several clinical scenarios, and its strengths have been demonstrated in the in-depth characterization of RV mechanical pattern and the prognostication of patients even in the face of maintained RV EF. Recently, various new features have been implemented in our software solution to enable the convenient, standardized, and more comprehensive analysis of RV function. Accordingly, in our current technical paper, we aim to provide a detailed description of the latest version of the ReVISION method with special regards to the volumetric partitioning of the RV and the calculation of longitudinal, circumferential, and area strains using 3DE datasets. We also report the results of the comparison between 3DE- and cardiac magnetic resonance imaging-derived RV parameters, where we found a robust agreement in our advanced 3D metrics between the two modalities. In conclusion, the ReVISION method may provide novel insights into global and also segmental RV function by defining parameters that are potentially more sensitive and predictive compared to conventional echocardiographic measurements in the context of different cardiac diseases.

Aim During surgery, a non‐invasive and easy‐to‐use method is required for evaluating left ventricular status. The systolic time interval, including pre‐ejection period (PEP), of left ventricle has been known to be correlated with cardiac contractility. In this study, we focused on the non‐invasive time interval from the Q wave of an electrocardiogram to the third component in the first heart sound (QS1‐3rd) and evaluated the correlation between PEP and peak differentiated left ventricular pressure (LV dp/dt). Methods Six adult anesthetized pigs were intubated. Mechanical ventilation was started. An electrocardiogram, carotid artery blood pressure, left ventricular pressure, and phonocardiogram on the fourth left intercostal space were monitored using a polygraph system. Cardiac output was measured by the thermodilution method. Data were simultaneously measured at baseline and after the infusion of noradrenaline, nitroprusside, esmolol sulfate, and dobutamine, respectively. Data were analyzed by Spearman’s rank correlation coefficient using four‐quadrant plot analysis. Results A total of 270 points were simultaneously measured. The QS1‐3rd showed a significant correlation with PEP (QS1‐3rd = 7.62 + 0.92 PEP; ρ = 0.91, P, The systolic time interval, including pre‐ejection period (PEP), of left ventricle has been known to be correlated with cardiac contractility. In this study, we focused on the non‐invasive time interval from the Q wave of the electrocardiogram to the third component in the first heart sound (QS1‐3rd) and evaluated the correlation between PEP and peak differentiated left ventricular pressure (LV dp/dt). This non‐invasive and easy‐to‐use hemodynamic parameter (QS1‐3rd) could be helpful for the management of perioperative patients, especially when echocardiography is not immediately available.

The U-shaped left ventricular (LV) contraction pattern, identified by MRI or echocardiography, is associated with improved CRT response. Gated SPECT MPI can measure both myocardial viability and mechanical dyssynchrony in a single scan. The aim of this study is to examine the relationship of the LV contraction pattern and the response of CRT in patients with left bundle branch block (LBBB). Fifty-eight patients who met CRT guidelines and who had pre-CRT MPI were enrolled. Myocardial segments with tracer uptake

International audience; Structural and functional dysfunction in both the macro- and microvasculature are a feature of essential hypertension. In a healthy cardiovascular system, the elastic properties of the large arteries ensure that pulsations in pressure and flow generated by cyclic left ventricular contraction are dampened, so that less pulsatile pressure and flow are delivered at the microvascular level. However, in response to aging, hypertension, and other disease states, arterial stiffening limits the buffering capacity of the elastic arteries, thus exposing the microvasculature to increased pulsatile stress. This is thought to be particularly pertinent to high flow/low resistance organs such as the brain and kidney, which may be sensitive to excess pressure and flow pulsatility, damaging capillary networks, and resulting in target organ damage. In this review, we describe the clinical relevance of the pulsatile interaction between the macro- and microvasculature and summarize current methods for measuring the transmission of pulsatility between the two sites.

Background Takotsubo cardiomyopathy (TCM) is diagnosed in 1–2% of all patients presenting with acute coronary syndrome (ACS). Clinical differences in individuals presenting with either the typical (apical) or atypical (midventricular, basal and focal) localization of left ventricular contraction abnormalities are not well understood. Methods We retrospectively analyzed 102 consecutive patients diagnosed with TCM based on clinical presentation, coronary angiography, and laevocardiography. Patients with different contraction abnormality patterns were compared regarding sex, clinical presentation, trigger for TCM, LV-function and LV enddiastolic pressure (LVEDP) as well as coronary artery disease. Results Of all TCM 102 patients, 69 (68%) presented with the typical pattern of apical contraction abnormality. 33 patients (32%) had an atypical pattern: 22 (22%) with the midventricular type, 2 (2%) with the basal type and 9 (9%) with a focal type. There was no difference in sex distribution among the different types of TCM (female: typical 86% vs atypical 85% p=0.83). Presentation as a ST-elevation ACS was more common in patients with atypical compared to typical TCM (21% vs. 17%; p=0.85), but without statistical significance. Cardiogenic shock (typical 6% vs atypical 3%; p=0.91) as well as intra-hospital death (typical 3% vs atypical 3%; p=0.56) were rare in both types. A trigger was not more common in patients with typical TCM (58% vs atypical 55%; p=0.91). The trigger was more often physical in typical (73%) and atypical TCM (78%) than psychological, but the distribution did not differ between the two types (p=0.92). 83.6% of the patients showed an impaired LV-EF. Median LV-EF in patients with typical TCM (35% (IQR 25–40)) tended to be lower than in patients with atypical TCM (40% (IQR 25–40); p=0.63; LV-EF ≤30% typical TCM 45% vs. atypical TCM 39%; p=0.75). In 72% (73/102) of the patients the LVEDP was determined. In 75% (55/73) the LVEDP was elevated (>15mmHg). LVEDP tended to be more often elevated in patients with typical TCM (83% vs. atypical 52%; p=0.11). Extent of coronary artery disease did not differ in the different types of TCM. Coronary stenosis >50% was rare (typical TCM 20% vs atypical TCM 9%; p=0.26), whereas exclusion of coronary artery disease was common in both types (typical TCM 71%; atypical TCM 76%; p=0.79). Conclusion While an apical contraction anomaly is the most common type of presentation in TCM, atypical contraction patterns are found in 32% of the patients. Overall, psychological triggers are not found as frequently in TCM as previously described. Patients with typical and atypical TCM do not differ in clinical presentation, LV-EF, LVEDP and extent of coronary artery disease.

Background His-bundle pacing is an emerging routine technique that avoids pacing-dependent side effects. However, the success rate of His-bundle pacing is not 100%.Methods and Results:Left bundle pacing or peri-left bundle pacing (LBP/peri-LBP) are recently developed techniques that directly capture the left bundle or ventricular tissue near the left bundle. We evaluated the success rate of LBP/peri-LBP in patients whose treatment with His-bundle pacing failed. In addition, we evaluated left ventricular contraction and desynchrony after LBP/peri-LBP. Conclusions LBP/peri-LBP is an alternative ventricular pacing method in atrioventricular block in patients with failure of His-bundle pacing.

WOS: 000390292600007 PubMed: 27695013 Objective The majority of risk factors for CAD are also encountered in patients with erectile dysfunction (ED). We aimed to investigate a possible association between left ventricular contraction dynamics and ED using speckle tracking echocardiography. Methods and results A total of 125 patients with ED were compared with 40 age-and sex-matched control subjects. ED was evaluated using the International Index of Erectile Function questionnaire. STE and global longitudinal strain (GLS) were assessed from two-, three- and four chamber apical images while global circumferencial strain (GCS) was evaluated using the parasternal short-axis images in left ventricular basal, mid and apical levels. GLS and GCS were detected to be more impaired in the ED group compared to controls (-17.3 +/- 2.6 vs -20.8 +/- 3.5, P < 0.05; -19.3 +/- 4.5 vs -21.3 +/- 3.7, P< 0.05, respectively). Systolic longitudinal and circumferential strain rates were also higher in the ED group compared to the controls (-1.2 +/- 0.3 vs -1.7 +/- 0.2, P < 0.005;-1.3 +/- 0.3 vs-1.6 +/- 0.5, P < 0.05, respectively) while longitudinal early and late diastolic strain rates were lower (1.3 +/- 0.8 vs 2.4 +/- 0.8, P < 0.05; 0.9 +/- 0.3 vs 1.4 +/- 0.2, P< 0.05 respectively). Circumferential early and late diastolic strain rates were similar between the two groups. Conclusions ED is associated with an increase in GLS and GCS even in the absence of overt CAD. Moreover, LV systolic dysfunction increases with increasing severity of ED. Strain and strain rate imaging seem to be a valuable method in the definition of high-risk patients.

Aim. Sport reserve training processes is are based on the set of characteristics of management, assessment of morphofunctional genetic features, age-related psychophysiological and informational components of physical fitness and their correlations, and the revealing of sport performance criteria. Organization. Basic evaluation of fitness involves gravitational and ballistic motor actions (MA), combination with survey training, special physical exercises, strength endurance development, stretching, and relaxation. Modern sports form extreme conditions of activity and impose tough requirements to the athlete’s body, scientific and technological support, organization and implementation of training process and competitions. In this respect, the scientific research concerning almost all kinds of sport focuses on the complex control of athletes’ functional status and fitness. Results. The paper specifies energy-supply components influencing sport performance in cyclic endurance-training sports. The main metabolic values were within the reference limits. Cardiac cycle values were wihtin the range of 0.89 ± 0.02 and 0.98 ± 0.03 s; PO2 interval was within the range of 0.17 ± 0.02 s and 20.15 ± 0.01 s (0.125–0.165s). O2RS complex was within the range of 0.10 and 0.8 s (0.06 – 0.10 s). The critical systole duration was 0.37 ± 0.004 and 0.36 ± 0.003 s (0.355–0.400 s). Myocardial mass was 195.60 ± 5.30 and 199.72 ± 6.12, and left ventricular contraction was – 63.40 ± 4.27% and 60.29 ± 3.89%. Most indicators of respiratory and gas exchange functions in orienteering athletes were within the reference limits. Conclusion. Criteria determining the possibility to include the given indicators in the control program and technology are their informational value, reliability, and correspondence to the sport training process direction. The most informative parameters in the control process are the indicators relevant to the specific of loads applied at the given stage of training. The preparedness of main functional systems in the athlete’s body changes not only from stage to stage in the course of the long-term training, but aso during different cycles of training.

Background: Long-QT syndrome (LQTS) is primarily an electrical disorder characterized by a prolonged myocardial action potential. The delay in cardiac repolarization leads to electromechanical (EM) abnormalities, which adds a diagnostic value for LQTS. Prolonged left ventricular (LV) contraction was identified as a potential risk for arrhythmia. The aim of this meta-analysis was to assess the best predictor of all EM parameters for cardiac events (CEs) in LQTS patients. Methods: We systematically searched all electronic databases up to March 2020, to select studies that assessed the relationship between echocardiographic indices&mdash, contraction duration (CD), mechanical dispersion (MD), QRS onset to peak systolic strain (QAoC), and the EM window (EMW), and electrical indices&mdash, corrected QT interval (QTC), QTC dispersion, RR interval in relation to CEs in LQTS. This meta-analysis included a total of 1041 patients and 373 controls recruited from 12 studies. Results: The meta-analysis showed that LQTS patients had electrical and mechanical abnormalities as compared to controls&mdash, QTC, WMD 72.8, QTC dispersion, WMD 31.7, RR interval, WMD 91.5, CD, WMD 49.2, MD, WMD 15.9, QAoC, WMD 27.8, and EMW, WMD &minus, 62.4. These mechanical abnormalities were more profound in symptomatic compared to asymptomatic patients in whom disturbances were already manifest, compared to controls. A CD &ge, 430 ms had a summary sensitivity (SS) of 71%, specificity of 84%, and diagnostic odds ratio (DOR) &gt, 19.5 in predicting CEs. EMW and QTC had a lower accuracy. Conclusions: LQTS is associated with pronounced EM abnormalities, particularly prolonged LV myocardial CD, which is profound in symptomatic patients. These findings highlight the significant role of EM indices like CD in managing LQTS patients.

Desynchronization of left ventricular contraction with right ventricular apical pacing is a known etiology of cardiomyopathy post pacemaker placement. An 82-year-old male with recent pacemaker for suspected sick sinus syndrome, has multiple recent admissions for dyspnea and fatigue. Clinical

The health effects of individual criteria air pollutants have been well investigated. However, little is known about the health effects of air pollutant mixtures that more realistically represent environmental exposures. The present study was designed to evaluate the cardiac effects of inhaled simulated smog atmospheres (SA) generated from the photochemistry of either gasoline and isoprene (SA-G) or isoprene (SA-Is) in mice. Four-month-old female mice were exposed for 4 h to filtered air (FA), SA-G, or SA-Is. Immediately and 20 h after exposure, cardiac responses were assessed with a Langendorff preparation using a protocol consisting of 20 min of global ischemia followed by 2 h of reperfusion. Cardiac function was measured by index of left-ventricular developed pressure (LVDP) and cardiac contractility (dP/dt) before ischemia. Pre-ischemic LVDP was lower in mice immediately after SA-Is exposure (52.2 ± 5.7 cm H2O compared to 83.9 ± 7.4 cm H2O after FA exposure; p = 0.008) and 20 h after SA-G exposure (54.0 ± 12.7 cm H2O compared to 79.3 ± 7.4 cm H2O after FA exposure; p = 0.047). Pre-ischemic left ventricular contraction dP/dtmax was lower in mice immediately after SA-Is exposure (2025 ± 169 cm H2O/sec compared to 3044 ± 219 cm H2O/sec after FA exposure; p

A computational method is presented in this paper for determining the severity of myocardial infarction of the left ventricle (LV) using its image data. In-silico generated displacement fields for a healthy and damaged LV are used to mimic imaging modalities by adding appropriate levels of noise. To reconstruct the contraction force from the displacement field, a composite material model of the LV is optimized using genetic algorithms and a neural network to return the contraction force and distribution of forces for infarct tissue. The healthy LV contraction force was accurately returned within 1% for all displacement field tests indicating that all imaging methods could be used to measure healthy patient LV displacement fields for the purpose of contraction force reconstruction. With the damaged LV, contraction forces of the healthy region, as well as infarct border and infarct regions were considered. The optimization model found the contraction force distribution within 2% for the healthy region, while for the border zone and infarct regions the average contraction force reconstruction errors were 8.4 kPa and 5.1 kPa, respectively. These errors are reasonably small while no significant SNR dependence was observed. The inverse problem algorithm provided good estimates regardless of the SNR, however, further training of the neural network system is required to improve the robustness of the inversion framework with low contraction forces, since the accuracy of the optimization limited the SNR response.

MacIver and Townsend's hypothesis predicts, based on a mathematical model of left ventricular contraction, that preserved absolute radial wall thickening (radWT) due to left ventricular hypertrophy is responsible for the normal ejection fraction in patients with heart failure with preserved ejection fraction (HFPEF).We tested the validity of this hypothesis by detailed echocardiography including evaluation of ventricular myocardial strain (S) using speckle tracking imaging in at least 60-year-old 18 controls and 94 hypertensive patients with normal ejection fraction.Echocardiography revealed no left ventricular diastolic dysfunction in 38 out of 94 (40%) patients with hypertension (HTDD-negative group), and 56 out of 94 (60%) patients had diastolic dysfunction (HTDD-positive groups). The absolute values of global longitudinal left ventricular peak systolic S were significantly reduced in both patient groups (P 0.05 for HTDD-negative, P 0.01 for HTDD-positive groups) vs. the controls. There were no significant between-groups differences in circumferential and radial peak left ventricular systolic Ss, radWT and ejection fraction. Left ventricular mass (LVM) (P 0.001), LVM/BMI (P 0.01) increased in the HTDD-positive group and ejection fraction/LVM/BMI decreased in both patient groups (P 0.01 for HTDD-negative, P 0.001 for HTDD-positive groups) vs. the controls. LVM increased, ejection fraction/LVM/BMI decreased in the HTDD-positive group vs. the HTDD-negative group (P 0.05 and P 0.01, respectively).We demonstrated decreased longitudinal left ventricular systolic function and showed that preserved ejection fraction was due to preserved absolute radWT and not due to increased radial or circumferential systolic function in patients with hypertension and normal ejection fraction, a potential HFPEF precursor condition. Instead of ejection fraction, rather ejection fraction/LVM/BMI might be used to detect subtle left ventricular systolic dysfunction in hypertension and HFPEF.

OBJECTIVES The aim of this study was to compare the volumetric response and the long- term survival after cardiac resynchronization therapy (CRT) in patients with intrinsic left bundle branch block (LBBB) versus chronic right ventricular pacing (RVP) with respect to the presence of mechanical dyssynchrony (MD). BACKGROUND Chronic RVP induces an iatrogenic LBBB and asynchronous left ventricular contraction that is potentially reversible by upgrading to CRT. METHODS A total of 914 patients eligible for CRT (117 with conventional pacemakers and 797 with intrinsic LBBB) were included in the study. MD was visually assessed before CRT and was defined as the presence of either apical rocking and/or septal flash on baseline echocardiograms. Patients with a left ventricular end-systolic volume decrease of >= 15% during the follow-up were considered responders. Patients were followed for all-cause mortality during the median follow-up of 48 months (interquartile range: 29 to 66 months). RESULTS MDwas observed in 51% of patientswithRVP versus 77% in patients with intrinsic LBBB( p< 0.001). Patients with RVP and MD had a similar likelihood of volumetric response as did patients with intrinsic LBBB and MD (adjusted odds ratio: 0.71; 95% confidence interval: 0.33 to 1.53; p - 0.385). There was no significant difference in long-term survival between patients with RVP and intrinsic LBBB (adjusted hazard ratio: 1.101; 95% confidence interval: 0.658 to 1.842; p = 0.714). Patients with visual MD and either intrinsic LBBB or RVP had a more favorable survival than those without MD (p < 0.001). CONCLUSIONS The likelihood of volumetric response and a favorable long-term survival of patients with RVP was similar to those of patients with intrinsic LBBB and were mainly determined by the presence of MD and not by the nature of LBBB. (C) 2017 by the American College of Cardiology Foundation.

Background Prevalence of myocardial bridging of the left anterior descending coronary artery (LAD) in patients with takotsubo syndrome (TTS) has been demonstrated. However, the impact of myocardial bridging on in-hospital outcome has not been fully evaluated. Methods A total of 144 consecutive patients with TTS were enrolled. Coronary angiography and left ventriculography were performed in all patients and absence of obstructive coronary disease explaining the left ventricular contraction abnormality was confirmed. Myocardial bridging was diagnosed when a dynamic compression in systole, so-called “milking effect”, was observed in the LAD. We evaluated differences in the clinical characteristics and in-hospital outcome between patients with and without myocardial bridging. Furthermore, multiple logistic regression analysis was performed to predict in-hospital death. Results Myocardial bridging was observed in 33 patients (23%). In-hospital death was more frequent in patients with myocardial bridging (21% vs. 6%, p = 0.02), which was due mainly to a higher non-cardiac death in those patients (15% vs. 5%, p = 0.049). Multiple logistic regression analysis demonstrated myocardial bridging (odds ratio = 12.0, 95% CI = 2.52–78.5, p Conclusion Myocardial bridging is an independent predictor of in-hospital death in patients with TTS.

Objectives The purpose of this study was to determine the mathematical relationship between left ventricular ejection fraction and global myocardial strain. A reduction in myocardial strain would be expected to cause a fall in ejection fraction. However, there is abundant evidence that abnormalities of myocardial strain can occur with a normal ejection fraction. Explanations such as a compensatory increase in radial or circumferential strain are not supported by clinical studies. We set out to determine the biomechanical relationship between ejection fraction, wall thickness and global myocardial strain. Methods The study used an established abstract model of left ventricular contraction to examine the effect of global myocardial strain and wall thickness on ejection fraction. Equations for the relationship between ejection fraction, wall thickness and myocardial strain were obtained using curve fitting methods. Results The mathematical relationship between ejection fraction, ventricular wall thickness and myocardial strain was derived as follows: φ = e(0.14Ln(ε) + 0.06)ω + (0.9Ln(ε) + 1.2), where φ is ejection fraction (%), ω is wall thickness (cm) and ε is myocardial strain (−%). Conclusion The findings of this study explain the coexistence of reduced global myocardial strain and normal ejection fraction seen in clinical observational studies. Our understanding of the pathophysiological processes in heart failure and associated conditions is substantially enhanced. These results provide a much better insight into the biophysical inter-relationship between myocardial strain and ejection fraction. This improved understanding provides an essential foundation for the design and interpretation of future clinical mechanistic and prognostic studies., Highlights • Ejection fraction has a limited value in predicting mortality and functional capacity. • Myocardial mechanics including the relationship between myocardial strain and ejection fraction are currently poorly understood. • We showed that there is biophysical relationship between end-diastolic wall thickness, myocardial strain and ejection fraction. • Such a relationship explains the poor correlation of ejection fraction with prognosis and functional capacity. • The study provides the foundation for determining the relationship between ventricular hypertrophy, ejection fraction and prognosis. • words

Background The changes of left ventricular function after undergoing a Ross-Konno operation for pediatric patients with multiple-level left ventricular outflow tract obstruction are still unclear. Methods From 1996 to 2006, 14 patients younger than 20 years underwent a Ross-Konno operation. The mean age at the time of the operation was 6.6 ± 5.7 years. A postoperative catheter examination was performed at early (1.0 ± 0.4 years after the operation, n = 13), mid (3.3 ± 1.6 years, n = 9), and late (8.5 ± 2.5 years, n = 6) periods. The mean follow-up period was 10.1 ± 6.0 years (range, 0.1 to 17.2 years). Results There was 1 early death and no late deaths. The pressure gradient across the left ventricular outflow tract was well relieved from 62.4 ± 22.9 mm Hg at the preoperative period to 4.5 ± 7.2 mm Hg at the early postoperative period, 4.1 ± 3.5 mm Hg at the mid postoperative period, and 3.8 ± 3.7 mm Hg at the late postoperative period. The left ventricular ejection fraction significantly decreased from 0.73 ± 0.12 at the preoperative period to 0.60 ± 0.10 at the early postoperative period ( p = 0.00035), then improved to 0.64 ± 0.14 at the late postoperative period. The left ventricular end-diastolic volume normalized to 103 ± 37% of the normal volume at the late postoperative period. However, the left ventricular end-diastolic pressure did not decrease from 15.2 ± 6.1 mm Hg at the preoperative period, 12.5 ± 3.3 mm Hg at the early postoperative period, 13.1 ± 5.1 mm Hg at the mid postoperative period, or 12.7 ± 5.6 mm Hg at the late postoperative period. Conclusions The left ventricular contraction and volume normalized long after the Ross-Konno operation. However, the reduced ventricular compliance did not recover, although left ventricular outflow tract obstruction was well relieved.

Stress cardiomyopathy, also known as takotsubo cardiomyopathy, is a rapidly reversible form of acute heart failure classically triggered by stressful events. It is associated with a distinctive left ventricular contraction pattern described as apical akinesis/ballooning with hyperdynamic contraction of the basal segments in the absence of obstructive coronary artery disease. The traditional paradigm has expanded to include other causes, in particular chemotherapeutic drugs. The literature increasingly suggests an association between cancer, chemotherapeutic drugs, and stress cardiomyopathy. Chemotherapy-induced takotsubo cardiomyopathy is a relatively new phenomenon, but one that merits detailed attention to the elucidation of possible mechanistic links.

Subject-specific, or personalised, modelling is one of the main targets in current cardiac modelling research. The aim of this study is to assess the improvement in predictive power gained by introducing subject-specific fibre models within an electromechanical model of left ventricular contraction in rat. A quantitative comparison of a series of global rule-based fibre models with an image-based locally optimised fibre model was performed. Our results show small difference in the predicted values of ejection fraction, wall thickening and base-to-apex shortening between the fibre models considered. In comparison, much larger differences appear between predicted values and those measured in experimental images. Further study of the constitutive behaviour and architecture of cardiac tissue is required before electromechanical models can fully benefit from the introduction of subject-specific fibres. Additionally, our study shows that, in the current model, an orthotropic description of the tissue is preferable to a transversely isotropic one, for the metrics considered. © 2013 Springer-Verlag.

The role of speckle-tracking echocardiography in the assessment of chronic aortic regurgitation (AR) is not established. Load dependency may encumber the interpretation of strain measurements in the chronically overloaded left ventricle. The aim of this study was to investigate the mechanisms of left ventricular (LV) contraction patterns in asymptomatic patients with moderate to severe AR and preserved ejection fractions.In this prospective, cross-sectional study, 31 patients with moderate to severe AR, 15 elite endurance athletes, and 17 healthy control subjects were examined using three-dimensional speckle-tracking echocardiography. Global circumferential strain (GCS), global longitudinal strain (GLS), end-systolic circumferential wall stress (ESSc), end-systolic meridional wall stress (ESSm), and the wall stress ratio (ESSc/ESSm) were measured.LV end-diastolic volumes were similar in athletes and patients with AR and significantly larger than in healthy control subjects. Values of GLS in control subjects, athletes, and patients with AR were -18.8 ± 1.9%, -17.3 ± 2.0%, and -16.4± 2.0%, respectively (control subjects vs athletes and patients, P .05), whereas values of GCS were -16.9 ± 2.0%, -15.5 ± 1.9%, and -17.9 ± 2.6%, respectively (athletes vs control subjects and patients, P .01). The ESSc/ESSm ratio was lower in patients with AR (P .01). When adjusted for ESSm, GLS remained impaired in patients compared with control subjects and athletes (P = .015). On the other hand, GCS was better in patients with AR when adjusted for ESSc (P = .003).In compensated AR, relatively high GCS compensates for reduced GLS in a manner consistent with the preserved ejection fractions observed in these patients.

Transient stress-induced cardiomyopathies have been increasingly recognized and while rare, they tend to affect elderly women more than other demographic groups. One type, often called tako-tsubo cardiomyopathy (TTC), is typically triggered by significant emotional or physical stress and is associated with chest pain, electrocardiogram (ECG) changes and abnormal cardiac enzymes. Significant left ventricular regional wall motion abnormalities usually include an akinetic “ballooning” apex with normal or hyperdynamic function of the base. A second type, often called neurogenic stunned myocardium, typically associated with subarachnoid hemorrhage, also usually presents with ECG changes and positive enzymes, but the typical wall motion abnormalities seen include normal basal and apical left ventricular contraction with akinesis of the mid-cavity in a circumferential fashion. The pathophysiology, clinical care and typical courses, are reviewed.

The early appearance of ventricular fibrillation (VF) following acute myocardial infarction (MI) is associated with adrenergic effects and electrical interactions although some early "mechanical" changes may also occur. The aim of the present experimental study was to examine whether early changes in the functional geometry of left ventricular (LV) contraction may be associated with ventricular arrhythmias occurring during the first 120min of MI.In 11 swine left anterior descending (LAD) coronary artery ligation was performed. Aortic flow, LV end-diastolic pressure (LVEDP), LV long and short axis lengths were measured and their fractional shortening (FS) was calculated before and during the initial 120min period of MI.LV long axis FS and aortic flow decreased (p0.001) whereas LVEDP increased (p0.01) in all 11 animals within 30min following LAD ligation. LV long and short axis lengths and LV short axis FS did not change significantly. VF occurred in 5 of the 11 animals within this 30min period. LV short axis FS decreased (p0.05) in all 5 animals prior to VF and increased (p0.05) in all 6 animals without VF. In 3 of the 6 animals that had no VF during the initial 30min VF occurred later. Similarly, LV short axis FS decreased prior to VF in all those 3 animals. LV short axis FS did not decrease in any of the remaining 3 swine without VF during the same period of time.Early changes in the functional geometry of LV contraction, in the form of a reduction of LV short axis FS, are associated with a greater incidence of VF in experimental acute MI.

• Simplified method: According to Ritter' method [5], the AVD was considered as optimal if the terminationof theAwaveof transmitralfilling coincided with the onset of isovolumic left ventricular contraction. Optimal AV delay was calculated as “(AVlong − (QAshort − QAlong)”, hence optimal AV delay = “(AVlong + QAlong) − QAshort”. In fact, the sum of AVlong and QAlong, named AA, was regarded as the interval from the beginning of atrial electrical activity to the end of atrial con

Left bundle branch block (LBBB) has been classically depicted as an electrical delay of conduction manifested by a mechanical dysynchrony of left ventricular contraction with a decrease in systolic function. Until recently, direct correction of LBBB has not been able to be demonstrated. With

A 78-year-old woman with dilated cardiomyopathy was admitted for advanced dyspnoea and recurrent cardiac decompensation despite optimal medical therapy. Implantation of a cardiac resynchronization therapy (CRT) device was indicated according to current guidelines. The day before CRT implantation, three-dimensional echocardiography was performed together with coronary sinus (CS) rotation angiography, which identified two sites of latest mechanical left ventricular (LV) contraction with adjacently available target veins. This case presents the first description of CRT target vein selection using a combination of functional information on LV contraction with anatomical information on the CS venous tree. In this specific patient, the approach eventually necessitated placement of two LV leads.

Summary Objectives The purpose of this study was to explore the possibility of using our novel echocardiographic index of inefficient left ventricular (LV) contraction in patient selection for cardiac resynchronization therapy (CRT). Methods Forty consecutive patients with LV ejection fraction ≤35% were divided into 2 groups, 9 CRT candidates and 31 non-CRT candidates based on conventional criteria. A global LV time–area curve and regional LV time–area curves in 6 radial sectors were obtained using two-dimensional echocardiography in the short-axis view with speckle tracking. Fractional inefficient contraction (FIC, %) was calculated as follows: (1 − global LV area change/sum of regional LV area changes) × 100. LV dyssynergy and dyssynchrony were quantified as the standard deviations of minimal values of circumferential speckle-tracking strain and their timings in the 6 sectors, respectively. Results There was no significant difference in LV dyssynchrony between CRT candidates and non-CRT candidates (79 ± 61 ms vs. 58 ± 26 ms, respectively). In contrast, FIC was significantly larger in CRT candidates than in non-CRT candidates (15.7 ± 11.0% vs. 5.4 ± 3.5%, respectively, p = 0.0018), with less overlap between groups. FIC showed a positive correlation with dyssynchrony (r = 0.64) and a negative correlation with dyssynergy (r = −0.42). Conclusions Our novel echocardiographic index of inefficient LV contraction, which increases with more dyssynchrony or less dyssynergy, may prove more useful in patient selection for CRT than other indices that focus on LV temporal dyssynchrony alone.

Two-dimensional strain imaging allows rapid and accurate analysis of regional left ventricular (LV) systolic and diastolic mechanics in the longitudinal, radial, and circumferential directions. The aim of this study was to assess precisely the differences in early impairment of LV myocardial contraction and relaxation among the 3 directions in 70 patients with cardiovascular risk factors and preserved LV pump function.The patients were classified into 2 groups according to the ratio of early diastolic to atrial systolic velocity (E/A) of transmitral flow: E/Aor = 1 (n = 35, 57 +/- 6.8 years) or E/A1 (n = 35, 60 +/- 4.9 years). The longitudinal strain and strain rate curves were determined in apical 2- and 4-chamber views, and radial and circumferential strain and strain rate curves and LV torsion curve were determined in the parasternal short-axis views.The mean peak systolic longitudinal strain and strain rate were lower, whereas the mean peak systolic circumferential strain and strain rate were greater in the E/A1 group. There were no significant differences in the mean peak systolic radial strain and strain rate between the 2 groups. The mean peak early diastolic longitudinal strain rate was markedly lower in the E/A1 group. The mean peak LV strain rates during atrial systole in all 3 directions were greater in the E/A1 group. The mean peak LV systolic longitudinal strain and longitudinal strain rate during atrial systole were independent predictors related to E/A in all patients. There were no significant differences in torsion and torsional and untwisting rates between the 2 groups.LV myocardial contraction and relaxation were first impaired in the longitudinal direction among the 3 directions in subclinical patients with cardiovascular risk factors. However, LV pump function and LV filling were compensated by circumferential shortening at ventricular systole and 3 directional lengthenings at atrial systole, respectively.

Aims The prerequisite and the rationale for the benefit of cardiac resynchronization therapy (CRT) is that it is able to resynchronize left ventricular (LV) walls that have a delayed activation. Methods and results In 69 consecutive patients who underwent biventricular (BIV) pacemaker implantation, we assessed the magnitude of intraventricular resynchronization achieved by means of simultaneous (BIV 0) and sequential BIV pacing (with an individually optimized VV interval value among þ80 ms and 280 ms) using pulsed-wave tissue Doppler imaging techniques and in particular the measurement of the intra-LV electromechanical delay. The intra-LV delay was defined as the difference between the longest and the shortest activation time in the six basal segments of the LV. An abnormal intra-LV delay was defined as a value .41 ms. The intra-LV delay was 63+ 28 ms baseline, decreased to 44+ 26 ms with BIV 0 and to 26+ 15 ms with optimized BIV (P ¼ 0.001). BIV 0 determined the shortest delay in 28 (41%) patients (23+ 12 ms). In 41 (59%) patients, a better resynchronization was achieved with optimized VV intervals (LV first in 32 and RV first in 5) or single-chamber pacing (LV in 3 and RV in 1). With BIV 0, the intra-LV delay remained abnormal in 41% and was longer than baseline in 30% of patients compared with 9 and 12% with optimized BIV, respectively (P ¼ 0.001). Conclusion A sub-optimal resynchronization is achieved with simultaneous BIV pacing in most patients. A tailored programming of the relative contribution of RV and LV pacing forms the prerequisite for improving CRT results.

An uncoordinated left ventricular contraction sequence contributes significantly to the impaired hemodynamic function in patients with chronic heart failure. Cardiac resynchronization therapy with biventricular pacing may improve heart failure symptoms and exercise tolerance and reduce cardiac mortality in patients with severe chronic heart failure, depressed systolic left ventricular function (EF 120 ms. However, about one third of patients with implanted pacemakers do not respond favorably to resynchronisation therapy. This may be related to the limited diagnostic value of QRS duration for the identification of mechanical dyssynchrony. Echocardiography allows identification of mechanical dyssynchrony with a high diagnostic sensitivity and may improve the selection of patients suitable for biventricular pacing. This article discusses proposed echocrdiographic approaches for quantification of dyssynchrony.

The onset of ventricular depolarization defines the start of the pre-ejection period (PEP), which is commonly used as an index of myocardial contractility. Although the fiducial point for this onset has traditionally been the onset of the Q wave of the electrocardiogram (qPEP), the Q wave is not visible in some patients. Therefore, other measurement points have also been used in the literature, including the peak of the R wave (rPEP). However, there has been little systematic examination of measurement issues associated with the selection of the fiducial point for ventricular activation.

Cardiac involvement in systemic light chain amyloidosis carries poor prognosis. Amyloid deposition in the myocardium can alter regional left ventricular contraction and cause dyssynchrony. Cardiac resynchronization therapy (CRT) is an effective treatment strategy for patients with advanced heart failure and echocardiographic dyssynchrony. We report a clinical and echocardiographic response of a patient with amyloid cardiomyopathy, treated with a combination of chemotherapy and CRT.

Cardiac disease in diabetes presents as impaired left ventricular contraction and relaxation; however, the mechanisms underlying contractile protein dysfunction during the progression of disease are unknown. Accordingly, we assessed Ca2+-dependent tension development and tension-dependent ATP consumption (tension cost) in a rat model early (6 wk) and late (12 wk) after the onset of diabetes (50 mg/kg iv streptozotocin) using mechanical force- and enzyme-coupled UV absorbance measurements. Myofilament Ca2+ sensitivity and maximal tension were unchanged between groups at either time point. Cross-bridge cycling rate was significantly decreased in diabetes, as indexed by tension cost (early control 5.4 ± 0.4 and early diabetes 4.2 ± 0.3; and late control 6.0 ± 0.2 and late diabetes 4.2 ± 0.2; P < 0.05). Because rodent models of cardiac disease are confounded by altered myosin isoform distribution, myosin content was determined by SDS-PAGE and densitometry. The cardiac content of α-myosin in diabetes was decreased to 41% ± 4.1 at 6 wk and 32.5% ± 2.9 at 12 wk of diabetes (early control 77.8% ± 3.3 and late control 73.6% ± 2.5). Separate control experiments demonstrated a linear decrease in tension cost with decreased α-myosin content. Given this, the depression of tension cost in this rodent model of diabetes could be fully explained by the altered myosin isoform distribution.