Influence of Alterations in Loading on Mitral Annular Velocity by Tissue Doppler Echocardiography and Its Associated Ability To Predict Filling Pressures

Protein kinase N promotes cardiac fibrosis in heart failure by fibroblast-to-myofibroblast conversion

Chronic fibrotic tissue disrupts various organ functions. Despite significant advances in therapies, mortality and morbidity due to heart failure remain high, resulting in poor quality of life. Beyond the cardiomyocyte-centric view of heart failure, it is now accepted that alterations in the interstitial extracellular matrix (ECM) also play a major role in the development of heart failure. Here, we show that protein kinase N (PKN) is expressed in cardiac fibroblasts. Furthermore, PKN mediates the conversion of fibroblasts into myofibroblasts, which plays a central role in secreting large amounts of ECM proteins via p38 phosphorylation signaling. Fibroblast-specific deletion of PKN led to a reduction of myocardial fibrotic changes and cardiac dysfunction in mice models of ischemia-reperfusion or heart failure with preserved ejection fraction. Our results indicate that PKN is a therapeutic target for cardiac fibrosis in heart failure.

Impact of cord clamping on haemodynamic transition in term newborn infants

OBJECTIVE

To assess the haemodynamic consequences of cord clamping (CC) in healthy term infants.

DESIGN

Cohort study.

SETTING

Tertiary maternity hospital.

PATIENTS

46 full-term vigorous infants born by caesarean section.

INTERVENTIONS

Echocardiography was performed before CC, immediately after CC and at 5 min after birth.

MAIN OUTCOME MEASURES

Pulsed wave Doppler-derived cardiac output and the pulmonary artery acceleration time indexed to the right ventricle ejection time were obtained. As markers of loading fluctuations, the myocardial performance indexes and the velocities of the tricuspid and mitral valve annuli were determined with tissue Doppler imaging. Heart rate was derived from Doppler imaging throughout the assessments.

RESULTS

Left ventricular output increased throughout the first minutes after birth (mean (SD) 222.4 (32.5) mL/kg/min before CC vs 239.7 (33.6) mL/kg/min at 5 min, p=0.01), while right ventricular output decreased (306.5 (48.2) mL/kg/min before vs 272.8 (55.5) mL/kg/min immediately after CC, p=0.001). The loading conditions of both ventricles were transiently impaired by CC, recovering at 5 min. Heart rate progressively decreased after birth, following a linear trend temporarily increased by CC. The variation in left ventricular output across the CC was directly correlated to the fluctuation of left ventricular preload over the same period (p=0.03).

CONCLUSIONS

This study illustrates the cardiovascular consequences of CC in term vigorous infants and offers insight into the haemodynamic transition from fetal to neonatal circulation in spontaneously breathing newborns. Strategies that aim to enhance left ventricular preload before CC may prevent complications of perinatal cardiovascular imbalance.

Mechanistic validation of the 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging Guidelines for the assessment of diastolic dysfunction in heart failure with reduced ejection fraction

Background

The American Society for Echocardiography/European Association of Cardiovascular Imaging (ASE/EACVI) 2016 guidelines for assessment of diastolic dysfunction (DD) are based primarily on the effects of diastolic dysfunction on left ventricular filling hemodynamics. However, these measures do not provide quantifiable mechanistic information about diastolic function. The Parameterized Diastolic Filling (PDF) formalism is a validated theoretical framework that describes DD in terms of the physical properties of left ventricular filling.

Aims

We hypothesized that PDF analysis can provide mechanistic insight into the mechanical properties governing higher grade DD.

Methods

Patients referred for echocardiography showing reduced left ventricular ejection fraction (< 45%) were prospectively classified into DD grade according to 2016 ASE/EACVI guidelines. Serial E-waves acquired during free breathing using pulsed wave Doppler of transmitral blood flow were analyzed using the PDF formalism.

Results

Higher DD grade (grade 2 or 3, n = 20 vs grade 1, n = 30) was associated with increased chamber stiffness (261 ± 71 vs 169 ± 61 g/s², p < 0.001), increased filling energy (2.0 ± 0.9 vs 1.0 ± 0.5 mJ, p < 0.001) and greater peak forces resisting filling (median [interquartile range], 18 [15–24] vs 11 [8–14] mN, p < 0.001). DD grade was unrelated to chamber viscoelasticity (21 ± 4 vs 20 ± 6 g/s, p = 0.32). Stiffness was inversely correlated with ejection fraction (r = − 0.39, p = 0.005).

Conclusions

Higher grade DD was associated with changes in the mechanical properties that determine the physics of poorer left ventricular filling. These findings provide mechanistic insight into, and independent validation of the appropriateness of the 2016 guidelines for assessment of DD.

Clinical Usefulness of an Echo-Doppler Model in Predicting Elevated Pulmonary Capillary Wedge Pressure in Patients With Heart Failure

Although several tissue-Doppler imaging (TDI) models for pulmonary capillary wedge pressure (PCWP) estimation have been reported, their reliability remains uncertain. Our previous theoretical and experimental analyses suggest that right atrial pressure (RAP) corrected by tissue-Doppler imaging tricuspid/mitral annular peak systolic velocities (S_T/S_M) (RAP × S_T/S_M) reliably predicts elevated PCWP. We sought to investigate its clinical usefulness for predicting elevated PCWP in heart failure (HF) patients. Ninety-eight patients admitted with HF who underwent right heart catheterization were prospectively studied. RAP and PCWP were measured by right heart catheterization. Simultaneously, S_T/S_M, early diastolic transmitral flow velocity to mitral annular velocity ratio (E/Ea), and diameter of inferior vena cava at inspiration (IVCDi), a noninvasive surrogate for RAP, were measured by echocardiography. RAP correlated with IVCDi (R² = 0.57). A significantly stronger correlation was observed between IVCDi corrected by S_T/S_M (IVCDi × S_T/S_M) and PCWP than between E/Ea and PCWP (R² = 0.47 vs 0.18). Receiver-operating characteristic analyses indicated that IVCDi × S_T/S_M >16 mm predicted PCWP >18 mm Hg with 90% sensitivity and 77% specificity, and the area under the curve was 0.86, which was significantly larger than that of E/Ea (area under the curve=0.72). In conclusions, IVCDi × S_T/S_M is a new useful noninvasive model to predict elevated PCWP in HF patients.

Review of Diagnostic and Therapeutic Approach to Canine Myxomatous Mitral Valve Disease

The most common heart disease that affects dogs is myxomatous mitral valve disease. In this article, we review the current diagnostic and therapeutic approaches to this disease, and we also present some of the latest technological advancements in this field.

A brief period of intensive cardiac rehabilitation improves global longitudinal strain and diastolic function after a first uncomplicated myocardial infarction

Objectives In patients with abnormal left ventricular ejection fraction (LVEF) after acute myocardial infarction (AMI), cardiac rehabilitation with physical training prevents cardiac remodelling. To define the role of rehabilitation in the recovery of ventricular function in less severe cases, we studied its effects on more refined indexes of left ventricular function in uncomplicated, low-risk patients. Methods and results Fifty-five patients underwent percutaneous coronary revascularization after uncomplicated first AMI. Thirty-four started cardiac rehabilitation with counselling and physical training; 21 patients did not train, followed a counselling program and were taken as controls. Echocardiography was performed at baseline, after rehabilitation or counselling program and at six months follow-up. We measured: global strain (GS%) with speckle tracking analysis, E/e' by tissue Doppler imaging (TDI), left ventricular elastance (K_LV) from the deceleration time (DT), LVEF, systolic and diastolic volumes, wall motion score index (WMSI). At baseline, groups had similar GS%, K_LV, LVEF, DT, E/e', systolic and diastolic volumes, WMSI. Rehabilitation increased peak VO₂ by 18% (P < 0.05) and improved GS%, K_LV, LVEF, E/e' and WMSI (P < 0.02) that were unchanged in controls. The improvement persisted at six months. Conclusions After a first uncomplicated AMI, abnormalities of left systolic and diastolic ventricular function may be present persisting over time despite a normal LVEF, which are fully reverted by cardiac rehabilitation.

Evaluation of Myocardial Injury using Standard Diagnostic Tools and Tissue Doppler Imaging in Blunt Trauma Chest

INTRODUCTION

Myocardial contusion is an entity in chest trauma which is difficult to diagnose. Current practice relies more on cardiac-specific biochemical markers and standard echocardiography, but no gold standard test exists. The application of Tissue Doppler imaging is yet unexplored.

AIM

The present study was designed to evaluate cardiac injury in patients with blunt trauma chest using conventional trans-thoracic echocardiography parameters and Tissue Doppler imaging.

MATERIALS AND METHODS

After ethical approval was taken from the Hospital and University and a written informed consent from all patients/attendants, this prospective study was conducted on a total of 30 patients in range of 15-60 years of age with blunt trauma chest. Patients with positive Trop-T and raised CPK (> 308 IU/L), raised CK-MB (> 24 IU/L) levels were suspected to have myocardial injury and were enrolled in the study. All patients fulfilling the inclusion criteria then underwent 2D-Echo and Tissue Doppler Imaging. Results of the observations were analysed using chi-square test.

RESULTS

Out of the total of 30 patients, 63.3% showed ECG changes suggestive of cardiac injury. A 76.7% patients suffered systolic dysfunction and 36.6% patients suffered diastolic dysfunction irrespective of ECG changes. On comparison of early filling velocity wave i.e., E wave (measured by transthoracic echocardiography) and tricuspid annular velocity Em wave (measured by tissue Doppler echocardiography) at tricuspid valve, we found statistically significant difference among two techniques. (p = 0.04).

CONCLUSION

Echocardiography is very sensitive parameter for evaluation of myocardial contusion. Tissue Doppler imaging provides additional and reliable information.

New Parameter Derived from Three-Dimensional Speckle-Tracking Echocardiography for the Estimation of Left Ventricular Filling Pressure in Nondilated Hearts

BACKGROUND

E/e' is clinically useful for the noninvasive assessment of left ventricular (LV) filling pressure. However, its use in some conditions is controversial, and angle dependence of the Doppler measurement and preload dependence of mitral e' in nondilated hearts represent major problems. The ratio of early filling rate derived from the time derivative of LV volume to early diastolic strain rate (FRe/SRe), similar to E/e', by three-dimensional (3D) speckle-tracking echocardiography has the potential to address such limitations. This study investigated whether FRe/SRe could estimate acute changes in LV filling pressure using the models of volume overload and myocardial ischemia in the nondilated heart.

METHODS

In 25 dogs, hemodynamic conditions were varied by acute volume overload and coronary occlusion. FRe and SRe were obtained from the same beat and automatically analyzed by the 3D speckle-tracking method, and global SRe was measured from longitudinal (L-SRe), circumferential (C-SRe), and area strain rate (A-SRe). E/e' was measured by two-dimensional echocardiography. LV pressure was derived from a micromanometer catheter and recorded simultaneously with the acquisition of the 3D images.

RESULTS

Mitral e' and L-SRe varied by changes in preload, whereas C-SRe and A-SRe did not. C-SRe and A-SRe were more strongly correlated with the time constant of LV relaxation than mitral e' and L-SRe. FRe/C-SRe and FRe/A-SRe had relatively high correlations with LV preatrial contraction (pre-A) pressure and end-diastolic pressure, but E/e' and FRe/L-SRe did not. Receiver operating characteristics curve analysis showed that FRe/C-SRe and FRe/A-SRe had larger areas under the curve for the estimation of increased LV filling pressure.

CONCLUSIONS

The novel parameter FRe/SRe has potential as a surrogate marker of LV filling pressure. Especially in nondilated hearts, FRe/C-SRe and FRe/A-SRe may be useful to more accurately predict LV filling pressure than E/e', although their applicability in dilated hearts requires further investigation.

The evolution of diastolic function during liver transplantation

INTRODUCTION

The peroperative management of liver transplantation is still associated with many cardiocirculatory complications in which diastolic dysfunction may play a contributive role. Transoesophageal echocardiography is a monitoring device commonly used in liver transplantation allowing diastolic function assessment.

METHODS

We prospectively analysed the peroperative transoesophageal echocardiography recordings of 40 patients undergoing liver transplantation in order to describe changes in diastolic function at different steps of the surgery. The diastolic function marker we used was the lateral mitral annulus motion (E' wave velocity) obtained by tissue-Doppler imaging. In addition, we also studied the left ventricular filling pressure indices and systolic function.

RESULTS

As a whole, there was no global change in E' wave velocity throughout the surgery. However, 11 patients (27.5%) presented a decrease in E' wave velocity up to 15% that identified an occurrence of diastolic function alteration. In this group, other peroperative data were not different from other patients (amount of bleeding, fluid administration or vasopressive support). Conversely, this group experienced lower preoperative E' wave velocity values (9cm·s^-1 versus 12cm·s^-1, P=0.05) and an increased incidence of postoperative cardiorespiratory complications (OR=6 [1-56], P=0.02). Considering all patients, 18 patients had an E' wave velocity under 10cm·s^-1 at unclamping, characterizing a diastolic dysfunction according to the usual criteria. This dysfunction was not associated with cardiorespiratory complications.

CONCLUSION

This work investigated peroperative systematic echocardiographic evaluation of diastolic function during liver transplantation. Diastolic dysfunction occurs frequently during liver transplantation and could lead to postoperative cardiorespiratory complications.

Echocardiographic evaluation of left ventricular diastolic function in cats: Hemodynamic determinants and pattern recognition

Left ventricular (LV) diastolic dysfunction is highly prevalent in cats and is a functional hallmark of feline cardiomyopathy. The majority of cats with hypertrophic, restrictive, and dilated cardiomyopathy have echocardiographic evidence of abnormal LV filling, even during the occult (preclinical) phase. Moderate and severe diastolic dysfunction is an indicator of advanced myocardial disease, is associated with clinical signs including exercise intolerance and congestive heart failure, affects outcome, and influences therapeutic decisions. Therefore, identification and quantification of LV diastolic dysfunction are clinically important. Surrogate measures of diastolic function determined by transthoracic two-dimensional, M-mode, and Doppler echocardiographic (DE) methods have been used widely for such purpose. Major functional characteristics of LV diastole, including global function, relaxation and untwist, chamber compliance, filling volume, and the resultant filling pressures can be semi-quantified by echocardiographic methods, and variables retrieved from transmitral flow, pulmonary vein flow, and tissue Doppler recordings are most frequently used. Although there is still a critical lack of well-designed studies in the field, knowledge has steadily accumulated over the past 20 years, reference ranges of diastolic echocardiographic variables have been determined, epidemiological studies have been conducted, and new treatments of diastolic dysfunction in cats have been evaluated. This report will give the reader a summary of the current status in the field of feline diastology with focus on the noninvasive diagnostic methods and interpretation of echocardiographic surrogate measures of LV diastolic function. Lastly, a grading system using a composite of left atrial size and various DE variables potentially useful in the functional classification of LV diastole in cats is introduced.

Experimentally Increasing the Compliance of Titin Through RNA Binding Motif-20 (RBM20) Inhibition Improves Diastolic Function In a Mouse Model of Heart Failure With Preserved Ejection Fraction

BACKGROUND

Left ventricular (LV) stiffening contributes to heart failure with preserved ejection fraction (HFpEF), a syndrome with no effective treatment options. Increasing the compliance of titin in the heart has become possible recently through inhibition of the splicing factor RNA binding motif-20. Here, we investigated the effects of increasing the compliance of titin in mice with diastolic dysfunction.

METHODS

Mice in which the RNA recognition motif (RRM) of one of the RNA binding motif-20 alleles was floxed and that expressed the MerCreMer transgene under control of the αMHC promoter (referred to as cRbm20^ΔRRM mice) were used. Mice underwent transverse aortic constriction (TAC) surgery and deoxycorticosterone acetate (DOCA) pellet implantation. RRM deletion in adult mice was triggered by injecting raloxifene (cRbm20^ΔRRM-raloxifene), with dimethyl sulfoxide (DMSO)-injected mice (cRbm20^ΔRRM-DMSO) as the control. Diastolic function was investigated with echocardiography and pressure-volume analysis; passive stiffness was studied in LV muscle strips and isolated cardiac myocytes before and after elimination of titin-based stiffness. Treadmill exercise performance was also studied. Titin isoform expression was evaluated with agarose gels.

RESULTS

cRbm20^ΔRRM-raloxifene mice expressed large titins in the hearts, called supercompliant titin (N2BAsc), which, within 3 weeks after raloxifene injection, made up ≈45% of total titin. TAC/DOCA cRbm20^ΔRRM-DMSO mice developed LV hypertrophy and a marked increase in LV chamber stiffness as shown by both pressure-volume analysis and echocardiography. LV chamber stiffness was normalized in TAC/DOCA cRbm20^ΔRRM-raloxifene mice that expressed N2BAsc. Passive stiffness measurements on muscle strips isolated from the LV free wall revealed that extracellular matrix stiffness was equally increased in both groups of TAC/DOCA mice (cRbm20^ΔRRM-DMSO and cRbm20^ΔRRM-raloxifene). However, titin-based muscle stiffness was reduced in the mice that expressed N2BAsc (TAC/DOCAcRbm20^ΔRRM-raloxifene). Exercise testing demonstrated significant improvement in exercise tolerance in TAC/DOCA mice that expressed N2BAsc.

CONCLUSIONS

Inhibition of the RNA binding motif-20-based titin splicing system upregulates compliant titins, which improves diastolic function and exercise tolerance in the TAC/DOCA model. Titin holds promise as a therapeutic target for heart failure with preserved ejection fraction.

Tissue Doppler imaging in fetuses with aortic stenosis and evolving hypoplastic left heart syndrome before and after fetal aortic valvuloplasty

OBJECTIVES

Fetal aortic valvuloplasty can improve filling and reduce afterload of the left ventricle in critical aortic stenosis. Success of an intrauterine intervention is currently measured by technical success, clinical survival and eventual postnatal biventricular physiology. In the present study we investigated the use of tissue Doppler imaging (TDI) to evaluate changes in ventricular function assessed before and after prenatal aortic valvuloplasty.

METHODS

Between October 2008 and December 2012, cardiac function was assessed by TDI before and after intervention in 23 fetuses that underwent technically successful valvuloplasty for critical aortic stenosis and in which postnatal outcome was known. The measurements were transformed into gestational age-independent Z-scores where appropriate.

RESULTS

Mean ± SD gestational age at intervention was 27.5 ± 3.1 weeks. Of the 23 fetuses, 14 had biventricular outcome. Before intervention all left ventricular (LV) TDI-derived parameters and mitral annular plane systolic excursion (MAPSE) were severely abnormal. It was possible to demonstrate considerably improved cardiac function after technically successful valvuloplasty. Among fetuses with postnatal biventricular outcome, TDI-derived LV myocardial peak velocity during early diastole (E') and myocardial peak velocity during systole in the ejection phase (S') significantly increased, E'/myocardial peak velocity during late diastole with atrial contraction (A') increased towards normal values, and LV transmitral-to-mitral-annular diastolic velocity ratio (E/E') and myocardial performance index (MPI') decreased but remained abnormally elevated. In addition, right ventricular A', S' and MPI' significantly improved after intervention.

CONCLUSION

Technically successful fetal aortic valvuloplasty led to significantly improved myocardial performance. It was possible to use TDI to detect distinct changes in ventricular function and TDI-derived parameters correlated with a biventricular outcome after birth. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

What global diastolic function is, what it is not, and how to measure it

Despite Leonardo da Vinci's observation (circa 1511) that “the atria or filling chambers contract together while the pumping chambers or ventricles are relaxing and vice versa,” the dynamics of four-chamber heart function, and of diastolic function (DF) in particular, are not generally appreciated. We view DF from a global perspective, while characterizing it in terms of causality and clinical relevance. Our models derive from the insight that global DF is ultimately a result of forces generated by elastic recoil, modulated by cross-bridge relaxation, and load. The interaction between recoil and relaxation results in physical wall motion that generates pressure gradients that drive fluid flow, while epicardial wall motion is constrained by the pericardial sac. Traditional DF indexes (τ, E/E′, etc.) are not derived from causal mechanisms and are interpreted as approximating either stiffness or relaxation, but not both, thereby limiting the accuracy of DF quantification. Our derived kinematic models of isovolumic relaxation and suction-initiated filling are extensively validated, quantify the balance between stiffness and relaxation, and provide novel mechanistic physiological insight. For example, causality-based modeling provides load-independent indexes of DF and reveals that both stiffness and relaxation modify traditional DF indexes. The method has revealed that the in vivo left ventricular equilibrium volume occurs at diastasis, predicted novel relationships between filling and wall motion, and quantified causal relationships between ventricular and atrial function. In summary, by using governing physiological principles as a guide, we define what global DF is, what it is not, and how to measure it.

Changes of Cardiac Function During Ultradistance Trail Running

Previous studies have noted reversible cardiac dysfunction during marathon races, but few data are available concerning ultradistance trail running. The aim of this study was to assess echocardiographic parameters during ultradistance trail running. We performed an observational study in 66 participants to the 80-km Ecotrail of Paris Ile de France. All subjects had echocardiographic examinations before the race and on arrival, and 28 of them underwent serial echocardiographic examinations during the race (21 and 53 km). A single experienced physician performed all echocardiographic examinations, and the same protocol was always used (conventional 2-dimensional and Doppler left ventricular parameters and longitudinal strain). All echocardiographic parameters of left ventricular (LV) systolic function were significantly decreased on arrival (p ≤0.002). A significant reduction of LV systolic function was observed in 48% of study subjects on arrival. No significant modification was observed at 21 or at 53 km, and only global longitudinal strain was significantly decreased (p = 0.0008). At arrival, mitral E/A ratio and average mitral tissue Doppler imaging e' wave were significantly decreased (p = 0.0001 and p = 0.0004, respectively), but these changes were observed from 21 km. In conclusion, ultradistance trail running can lead to abnormalities of LV systolic and diastolic functions in amateur runners. Diastolic dysfunction arises earlier than systolic dysfunction. Left ventricular systolic dysfunction occurred in 48% of the study subjects and was detected early by assessment of longitudinal strain.

Tissue Doppler indices of diastolic function in critically ill patients and association with mortality - a systematic review

PURPOSE

Systolic impairment is well reported in critically ill patients but diastolic function has been relatively understudied. The objective of this review was to assess tissue Doppler indices of diastolic function in critically ill patients along with any association with mortality.

METHODS

A systematic review of articles in English using Medline, EMBASE, CINAHL and the Cochrane database of systematic reviews. Search terms included diastolic function, diastolic dysfunction, diastolic abnormal*, diastolic heart failure, diastolic filling, ventricular relaxation, pulmonary artery occlusion pressure, left ventricular filling pressure, cardiac dysfunction, intensive care, critical care, critically ill, critical illness, sepsis and septic shock. Only studies of critically ill adult patients (excluding post-cardiac surgical patients) whose diastolic function was assessed using tissue Doppler imaging were included. Study quality was assessed using a modified version of the Newcastle-Ottawa Scale (NOS).

RESULTS

Nineteen studies were included, with a total of 1365 patients. All trials were observational. There was a large heterogeneity in patient populations and the methodology of tissue Doppler assessment of diastology resulting in a descriptive analysis. Patient groups included severe sepsis or septic shock (5 studies), septic shock (5 studies), systemic inflammatory response syndrome and shock (1 study), septic shock and acute lung injury (1 study), cancer and septic shock (2 studies), general ICU patients (1 study), combined medical and surgical ICU (2 studies) and sub-arachnoid haemorrhage patients (2 studies). Seventeen studies scored 5/6 on the NOS with the remaining two scoring 4/6. Fourteen studies reported on numbers of patients diagnosed with diastolic dysfunction (500/999, mean 50%, range 20-92%). Three studies found that diastolic dysfunction was an independent predictor of mortality.

CONCLUSIONS

Current data shows a large range in the incidence of diastolic dysfunction in this patient population and a variable link with mortality. Future research should focus on the definition of normal values for diastolic function in critically ill patients along with the effects of ICU therapies and consensus criteria for its assessment in this patient population.

Cardiac and renal function in a large cohort of amateur marathon runners

Background

Participation of amateur runners in endurance races continues to increase. Previous studies of marathon runners have raised concerns about exercise-induced myocardial and renal dysfunction and damage. In our pooled analysis, we aimed to characterize changes of cardiac and renal function after marathon running in a large cohort of mostly elderly amateur marathon runners.

Methods

A total of 167 participants of the BERLIN-MARATHON (female n = 89, male n = 78; age = 50.3 ± 11.4 years) were included and cardiac and renal function was analyzed prior to, immediately after and 2 weeks following the race by echocardiography and blood tests (including cardiac troponin T, NT-proBNP and cystatin C).

Results

Among the runners, 58% exhibited a significant increase in cardiac biomarkers after completion of the marathon. Overall, the changes in echocardiographic parameters for systolic or diastolic left and right ventricular function did not indicate relevant myocardial dysfunction. Notably, 30% of all participants showed >25% decrease in cystatin C-estimated glomerular filtration rate (GFR) from baseline directly after the marathon; in 8%, we observed a decline of more than 50%. All cardiac and renal parameters returned to baseline ranges within 2 weeks after the marathon.

Conclusions

The increase in cardiac biomarkers after completing a marathon was not accompanied by relevant cardiac dysfunction as assessed by echocardiography. After the race, a high proportion of runners experienced a decrease in cystatin C-estimated GFR, which is suggestive of transient, exercise-related alteration of renal function. However, we did not observe persistent detrimental effects on renal function.

Electronic supplementary material

The online version of this article (doi:10.1186/s12947-015-0007-6) contains supplementary material, which is available to authorized users.

Beneficial effects of elevating cardiac preload on left-ventricular diastolic function and volume during heat stress: implications toward tolerance during a hemorrhagic insult

Volume loading normalizes tolerance to a simulated hemorrhagic challenge in heat-stressed individuals, relative to when these individuals are thermoneutral. The mechanism(s) by which this occurs is unknown. This project tested two unique hypotheses; that is, the elevation of central blood volume via volume loading while heat stressed would 1) increase indices of left ventricular diastolic function, and 2) preserve left ventricular end-diastolic volume (LVEDV) during a subsequent simulated hemorrhagic challenge induced by lower-body negative pressure (LBNP). Indices of left ventricular diastolic function were evaluated in nine subjects during the following conditions: thermoneutral, heat stress, and heat stress after acute volume loading sufficient to return ventricular filling pressures toward thermoneutral levels. LVEDV was also measured in these subjects during the aforementioned conditions prior to and during a simulated hemorrhagic challenge. Heat stress did not change indices of diastolic function. Subsequent volume infusion elevated indices of diastolic function, specifically early diastolic mitral annular tissue velocity (E') and early diastolic propagation velocity (E) relative to both thermoneutral and heat stress conditions (P < 0.05 for both). Heat stress reduced LVEDV (P < 0.05), while volume infusion returned LVEDV to thermoneutral levels. The reduction in LVEDV to LBNP was similar between thermoneutral and heat stress conditions, whereas the reduction after volume infusion was attenuated relative to both conditions (P < 0.05). Absolute LVEDV during LBNP after volume loading was appreciably greater relative to the same level of LBNP during heat stress alone. Thus, rapid volume infusion during heat stress increased indices of left ventricular diastolic function and attenuated the reduction in LVEDV during LBNP, both of which may serve as mechanisms by which volume loading improves tolerance to a combined hyperthermic and hemorrhagic challenge.

A novel technique to predict pulmonary capillary wedge pressure utilizing central venous pressure and tissue Doppler tricuspid/mitral annular velocities

Assessing left ventricular (LV) filling pressure (pulmonary capillary wedge pressure, PCWP) is an important aspect in the care of patients with heart failure (HF). Physicians rely on right ventricular (RV) filling pressures such as central venous pressure (CVP) to predict PCWP, assuming concordance between CVP and PCWP. However, the use of this method is limited because discordance between CVP and PCWP is observed. We hypothesized that PCWP can be reliably predicted by CVP corrected by the relationship between RV and LV function, provided by the ratio of tissue Doppler peak systolic velocity of tricuspid annulus (S(T)) to that of mitral annulus (S(M)) (corrected CVP:CVP·S(T)/S(M)). In 16 anesthetized closed-chest dogs, S T and S M were measured by transthoracic tissue Doppler echocardiography. PCWP was varied over a wide range (1.8-40.0 mmHg) under normal condition and various types of acute and chronic HF. A significantly stronger linear correlation was observed between CVP·S(T)/S(M) and PCWP (R2 = 0.78) than between CVP and PCWP (R2 = 0.22) (P < 0.01). Receiver-operating characteristic (ROC) analysis indicated that CVP·S(T)/S(M) >10.5 mmHg predicted PCWP >18 mmHg with 85% sensitivity and 88% specificity. Area under ROC curve for CVP·S T/S M to predict PCWP >18 mmHg was 0.93, which was significantly larger than that for CVP (0.66) (P < 0.01). Peripheral venous pressure (PVP) corrected by S T/S M (PVP·S(T)/S(M) also predicted PCWP reasonably well, suggesting that PVP·S(T)/S (M) may be a minimally invasive alternative to CVP·S(T)/S(M) In conclusion, our technique is potentially useful for the reliable prediction of PCWP in HF patients.

Point of care cardiac ultrasound applications in the emergency department and intensive care unit--a review

The use of point of care echocardiography by non-cardiologist in acute care settings such as the emergency department (ED) or the intensive care unit (ICU) is very common. Unlike diagnostic echocardiography, the scope of such point of care exams is often restricted to address the clinical questions raised by the patient's differential diagnosis or chief complaint in order to inform immediate management decisions. In this article, an overview of the most common applications of this focused echocardiography in the ED and ICU is provided. This includes but is not limited to the evaluation of patients experiencing hypotension, cardiac arrest, cardiac trauma, chest pain and patients after cardiac surgery.

Respiratory changes in the E/A wave pattern can be an early sign of diastolic dysfunction: an echocardiographic long-term follow-up study

BACKGROUND

The left ventricular filling pattern may show changes during respiration, which are generally used in the diagnosis of diastolic dysfunction. The clinical importance of the respiratory E/A wave pattern change has been investigated in a limited number of studies. The aim of the present study was to assess the diastolic function of hypertensive patients with respiratory changes in mitral flow over a long-term follow-up period.

MATERIAL/METHODS

Our study included 107 newly diagnosed and untreated hypertensive patients (49 males; mean age, 46±10 years) with respiratory changes during transthoracic echocardiography (TTE). In addition, the patient group was classified into 2 groups according to the change in E/A pattern by the Valsalva maneuver. After a mean follow-up period of 44±7 month, 90% of the hypertensive patients and the entire control group were re-examined.

RESULTS

Relaxation abnormalities developed in 84% of the patients (58/80) in the Valsalva-positive group after the follow-up period. The frequency of relaxation abnormalities was 60% in the Valsalva-negative group and 3.1% in the control group (p<0.001). Based on multivariate regression analysis, the echocardiographic predictors of the development of relaxation impairment were mitral E velocity, A velocity, deceleration time, isovolumetric contraction time, E/E' ratio, and the presence of respiratory change. The most important parameter for the development of an abnormal relaxation pattern was the presence of respiratory change after adjustment according to the changes with the Valsalva maneuver.

CONCLUSIONS

Respiratory change in mitral flow can be evaluated as an early sign of diastolic dysfunction in patients with hypertension.

Echocardiographic Measures of Diastolic Function Are Preload Dependent during Triggered Positive Pressure Ventilation: A Controlled Crossover Study in Healthy Subjects

Background. The use of echocardiography in intensive care settings impacts decision making. A prerequisite for the use of echocardiography is relative resistance to changes in volume status and levels of positive pressure ventilation (PPV). Studies on indices of diastolic function report conflicting results with regard to dependence on volume status. Evidence is scarce on PPV. Methods. Ten healthy subjects were exposed to 6 levels of positive end-expiratory pressure (PEEP) and pressure support (PS) following a baseline reading. All ventilator settings were performed at three positions: horizontal, reverse-Trendelenburg, and Trendelenburg. Echocardiography was performed throughout. Results. During spontaneous breathing, early diastolic transmitral velocity (E) changed with positioning (P < 0.001), whereas early diastolic velocity of the mitral annulus (e') was independent (P = 0.263). With PPV, E and e' proved preload dependent (P   values < 0.001). Increases in PEEP, PS, or a combination influenced E and e' in reverse-Trendelenburg- and horizontal positions, but not in the Trendelenburg position. Discussion. The change towards preload dependency of e' with PPV suggests that PPV increases myocardial preload sensitivity. The susceptibility of E and e' to preload changes during PPV discourages their use in settings of volume shifts or during changes in ventilator settings. Conclusion. Positioning and PPV affect E and e'.

Influence of acute preload changes on mitral annulus velocity measured by tissue Doppler echocardiography in critically ill patients

AIM

The assessment of diastolic function remains difficult in critical care patients because of unstable preload conditions. Described as fairly insensitive to preload changes, tissue Doppler velocity measurement at the lateral mitral annulus (e' (lat) ) may help evaluate diastolic function. Our aim was to prospectively evaluate e' (lat) changes in relation to fluid expansion in critically ill patients.

METHODS

This prospective observational study was conducted in critically ill, mechanically ventilated, patients in sinus rhythm without previously known cardiac disease. Echocardiography was performed before and 1 hour after a fluid challenge (infusion of Gelofusine 500 ml in 30 minutes). Conventional pulsed wave Doppler indices of left ventricular diastolic function and tissue Doppler velocity lateral (e' (lat) ) and septal (e' (sept) ) mitral annulus velocity were measured, whereas hemodynamic data were simultaneously collected.

RESULTS

Twenty patients (age, 55 ± 15 years; Simplified Acute Physiology Score II, 45 ± 10) were enrolled. Systolic function was preserved in all patients. Cardiac index increased (p < 0.05), as did early diastolic mitral velocity (E wave) (p = 0.001), and e' (lat) and e' (sept) (p = 0.02) after fluid challenge.

CONCLUSIONS

This study confirms the preload dependence and limited clinical usefulness of most Doppler variables, such as e' (lat) , to evaluate diastolic function in intensive care unit patients. Indices, such as E/e', may be of interest in these cases.

Echocardiographic assessment of canine degenerative mitral valve disease

Degenerative mitral valve disease (MVD), the most common acquired heart disease in small-sized dogs, is characterized by valvular degeneration resulting in systolic mitral valve regurgitation (MR). Worsening of MR leads to several combined complications including cardiac remodeling, increased left ventricular filling pressure, pulmonary arterial hypertension, and myocardial dysfunction. Conventional two-dimensional, M-mode, and Doppler examination plays a critical role in the initial and longitudinal assessment of dogs affected by MVD, providing information on mitral valve anatomy, MR severity, left ventricular (LV) size and function, as well as cardiac and vascular pressures. Several standard echocardiographic variables have been shown to be related to clinical outcome. Some of these markers (e.g., left atrium to aorta ratio, regurgitation fraction, pulmonary arterial pressure) may also help in identifying asymptomatic MVD dogs at higher risk of early decompensation, which remains a major issue in practice. However, both afterload and preload are altered during the disease course. This represents a limitation of conventional techniques to accurately assess myocardial function, as most corresponding variables are load-dependent. Recent ultrasound techniques including tissue Doppler imaging, strain and strain rate imaging, and speckle tracking echocardiography, provide new parameters to assess regional and global myocardial performance (e.g., myocardial velocities and gradients, deformation and rate of deformation, and mechanical synchrony). As illustration, the authors present new data obtained from a population of 91 dogs (74 MVD dogs, 17 age-matched controls) using strain imaging, and showing a significant longitudinal systolic alteration at the latest MVD heart failure stage.

Noninvasive Estimation of the Rate of Relaxation by the Analysis of Intraventricular Pressure Gradients

Background—

During late ejection, myocardial relaxation causes systolic flow to decelerate and stop, and this phenomenon is coupled with the generation of a pressure gradient inside the left ventricle (LV). We hypothesized that the peak reverse ejection intraventricular pressure difference (REIVPD) between the LV apex and the outflow tract could be a useful method to improve the assessment of LV relaxation using Doppler echocardiography.

Methods and Results—

Three sets of animal experiments and 1 clinical study were designed. In 6 pigs, a close relationship between REIVPD and the intensity of the relaxation wave ( R rm =0.89) was demonstrated using wave intensity analysis of high-fidelity pressure-volume-velocity data. In 19 animals, REIVPD sensitively detected modifications of the lusotropic state and closely correlated with the time constant of LV relaxation (τ) within animals ( R rm =−0.93). Load-dependence analysis in 5 pigs showed that REIVPD remained stable up to values of 35% to 40% acute preload reduction. Clinical validation was tested in 50 patients (23 with normal systolic function) undergoing simultaneous Doppler echocardiography and high-fidelity LV pressure measurements on the same beat. REIVPD and tissue Doppler mitral annulus velocity (e′) were independently related to τ, but the REIVPD · e′ product correlated better with τ than either variable separately (bootstrap-corrected correlation coefficients: R =−0.84 versus −0.71, and −0.70, respectively, P <0.05). Area under the receiver operating characteristic curve to predict impaired relaxation (τ>50 ms) for e′ · REIVPD was 0.96 (95% confidence interval, 0.85 to 0.99).

Conclusions—

The Doppler-derived REIVPD provides a sensitive, reliable, reproducible, and relatively load-independent index of the rate of LV relaxation. Combined with tissue Doppler measurements of longitudinal function, this method improves noninvasive assessment of LV relaxation in the clinical setting.

Myocardial function and aerobic fitness in adolescent females

A recent report indicated that variations in myocardial functional (systolic and diastolic) responses to exercise do not contribute to inter-individual differences in aerobic fitness (peak VO(2)) among young males. This study was designed to investigate the same question among adolescent females. Thirteen highly fit adolescent football (soccer) players (peak VO(2) 43.5 ± 3.4 ml kg(-1) min(-1)) and nine untrained girls (peak VO(2) 36.0 ± 5.1 ml kg(-1) min(-1)) matched for age underwent a progressive cycle exercise test to exhaustion. Cardiac variables were measured by standard echocardiographic techniques. Maximal stroke index was greater in the high-fit group (50 ± 5 vs. 41 ± 4 ml m(-2)), but no significant group differences were observed in maximal heart rate or arterial venous oxygen difference. Increases in markers of both systolic (ejection rate, tissue Doppler S') and diastolic (tissue Doppler E', mitral E velocity) myocardial functions at rest and during the acute bout of exercise were similar in the two groups. This study suggests that among healthy adolescent females, like young males, myocardial systolic and diastolic functional capacities do not contribute to inter-individual variability in physiologic aerobic fitness.

Tissue Doppler of early mitral filling correlates with simulated volume loss in healthy subjects

OBJECTIVES

The accurate noninvasive assessment of preload in emergency department (ED) patients remains elusive. Point-of-care ultrasound (US) imaging, particularly evaluation of the inferior vena cava (IVC), has been shown to be qualitatively helpful. Doppler and tissue Doppler are now routinely available on ED US equipment, but few studies have looked at the correlation of dynamic changes in these parameters in a controlled model of hypovolemia. Our objective was to examine the correlation of Doppler parameters to simulated volume loss in healthy subjects using a lower-body negative pressure (LBNP) model and to compare these measurements to commonly used IVC measurements of preload.

METHODS

Twelve paid volunteers with no known cardiovascular disease between the ages of 23 and 31 years old (mean ± SD = 25.5 ± 2.5 years old) were recruited. Hypovolemia was simulated using graduated LBNP levels with measurements taken at 0, -30, and -60 mm Hg and lower pressures as tolerated. Vital signs were monitored in all patients. US measurements recorded at each negative pressure level included IVC maximum (IVC(max)) and minimum (IVC(min)) dimensions; early (E) and late (A) transmitral filling velocities using pulsed-wave spectral Doppler; and early (E') and late (A') tissue Doppler velocities at the septal ((sep)) and lateral ((lat)) mitral annulus, using pulsed-wave tissue Doppler.

RESULTS

Lower-body negative pressure correlated significantly and positively within subjects for all US parameters except for the A filling wave. E'(lat) and E'(sep) showed the strongest correlation with R² values of 0.749 (95% confidence interval [CI] = 0.577 to 0.854) and 0.738 (95% CI = 0.579 to 0.875) respectively, followed by A'(sep) 0.674 (95% CI = 0.416 to 0.845), IVC(max) 0.638 (95% CI = 0.425 to 0.806), A'(lat) 0.547 (95% CI = 0.280 to 0.802), IVC(min) 0.512 (95% CI = 0.192 to 0.777), and E 0.478 (95% CI = 0.187 to 0.762). Ratios correlated only moderately with LBNP level, including E/ E'(lat) R² of 0.430 (95% CI = 0.131 to 0.706), E/ E'(sep) 0.416 (95% CI = 0.183 to 0.686), and IVC collapsibility index (IVC(CI)) 0.201 (95% CI = 0.003 to 0.681). Vital signs, including heart rate and blood pressure, did not vary significantly with LBNP levels.

CONCLUSIONS

In this pilot study of healthy subjects, tissue Doppler assessment of early diastolic filling correlated most strongly with simulated hypovolemia.

Detection of congestive heart failure in dogs by Doppler echocardiography

BACKGROUND

Echocardiographic prediction of congestive heart failure (CHF) in dogs has not been prospectively evaluated.

HYPOTHESIS

CHF can be predicted by Doppler echocardiographic (DE) variables of left ventricular (LV) filling in dogs with degenerative mitral valve disease (MVD) and dilated cardiomyopathy (DCM).

ANIMALS

Sixty-three client-owned dogs.

METHODS

Prospective clinical cohort study. Physical examination, thoracic radiography, analysis of natriuretic peptides, and transthoracic echocardiography were performed. Diagnosis of CHF was based upon clinical and radiographic findings. Presence or absence of CHF was predicted using receiver-operating characteristic (ROC) curve, multivariate logistic and stepwise regression, and best subsets analyses.

RESULTS

Presence of CHF secondary to MVD or DCM could best be predicted by E:isovolumic relaxation time (IVRT) (area under the ROC curve [AUC]=0.97, P<.001), respiration rate (AUC=0.94, P<.001), Diastolic Functional Class (AUC=0.93, P<.001), and a combination of Diastolic Functional Class, IVRT, and respiration rate (R2=0.80, P<.001) or Diastolic Functional Class (AUC=1.00, P<.001), respiration rate (AUC=1.00, P<.001), and E:IVRT (AUC=0.99, P<.001), and a combination of Diastolic Functional Class and E:IVRT (R2=0.94, P<.001), respectively, whereas other variables including N-terminal pro-brain natriuretic peptide, E:Ea, and E:Vp were less useful.

CONCLUSION AND CLINICAL IMPORTANCE

Various DE variables can be used to predict CHF in dogs with MVD and DCM. Determination of the clinical benefit of such variables in initiating, modulating, and assessing success of treatments for CHF needs further study.

Prognostic value of tissue Doppler-Derived E/e' on early morbid events after cardiac surgery

BACKGROUND

The tissue Doppler-derived surrogate for left ventricular diastolic pressure, E/e', has been used to prognosticate outcome in a variety of cardiovascular conditions. In this study, we determined the relationship of intraoperative E/e' to the use of inotropic support, duration of mechanical ventilation (MV), length of intensive care unit stay (ICU-LOS), and total hospital stay (H-LOS) in patients requiring cardiac surgery. The records of 245 consecutive patients were retrospectively reviewed to obtain 205 patients who had intraoperative transesophageal echocardiography examinations prior to coronary artery bypass grafting and/or valvular surgery. Cox proportional hazards and logistic regression models were used to analyze the relation between intraoperative E/e' or LVEF and early postoperative morbidity (H-LOS, ICU-LOS, and MV) and the probability that a patient would require inotropic support. With adjustments for other predictors (female gender, hypertension, diabetes, history of myocardial infarction, emergency surgery, renal failure, procedure type, and length of aortic cross-clamp time), an elevated E/e' ratio (>or=8) was significantly associated with an increased ICU-LOS (49 versus 41 median h, P = 0.037) and need for inotropic support (P = 0.002) while baseline LVEF was associated with inotropic support alone (P < 0.0001). These data suggest that the tissue Doppler-derived index of left ventricular diastolic filling pressure may be a useful indicator for predicting early morbid events after cardiac surgery, and may even provide additional information from that of baseline LVEF. Further, patients with elevated preoperative E/e' may need more careful peri- and postoperative management than those patients with E/e' <8.

Prediction of hospital outcome in septic shock: a prospective comparison of tissue Doppler and cardiac biomarkers

Introduction

Diastolic dysfunction as demonstrated by tissue Doppler imaging (TDI), particularly E/e' (peak early diastolic transmitral/peak early diastolic mitral annular velocity) is common in critical illness. In septic shock, the prognostic value of TDI is undefined. This study sought to evaluate and compare the prognostic significance of TDI and cardiac biomarkers (B-type natriuretic peptide (BNP); N-terminal proBNP (NTproBNP); troponin T (TnT)) in septic shock. The contribution of fluid management and diastolic dysfunction to elevation of BNP was also evaluated.

Methods

Twenty-one consecutive adult patients from a multidisciplinary intensive care unit underwent transthoracic echocardiography and blood collection within 72 hours of developing septic shock.

Results

Mean ± SD APACHE III score was 80.1 ± 23.8. Hospital mortality was 29%. E/e' was significantly higher in hospital non-survivors (15.32 ± 2.74, survivors 9.05 ± 2.75; P = 0.0002). Area under ROC curves were E/e' 0.94, TnT 0.86, BNP 0.78 and NTproBNP 0.67. An E/e' threshold of 14.5 offered 100% sensitivity and 83% specificity. Adjustment for APACHE III, cardiac disease, fluid balance and grade of diastolic function, demonstrated E/e' as an independent predictor of hospital mortality (P = 0.019). Multiple linear regression incorporating APACHE III, gender, cardiac disease, fluid balance, noradrenaline dose, C reactive protein, ejection fraction and diastolic dysfunction yielded APACHE III (P = 0.033), fluid balance (P = 0.001) and diastolic dysfunction (P = 0.009) as independent predictors of BNP concentration.

Conclusions

E/e' is an independent predictor of hospital survival in septic shock. It offers better discrimination between survivors and non-survivors than cardiac biomarkers. Fluid balance and diastolic dysfunction were independent predictors of BNP concentration in septic shock.

Usefulness of early diastolic mitral annular velocity to predict plasma levels of brain natriuretic peptide and transient heart failure development after device closure of atrial septal defect

Device closure of atrial septal defect (ASD) is sometimes followed by elevation of plasma brain natriuretic peptide (BNP), a marker of heart failure, and progression to heart failure. This study tested the hypothesis that the underlying diastolic dysfunction, assessed on tissue Doppler images (TDI) before device closure, can predict BNP level after ASD closure. The study subjects were 39 consecutive patients (age 27.5 +/- 16.3 years, range 5 to 63) who underwent device closure for ASD. Echocardiographic evaluation using TDI and 2-dimensional and pulse wave Doppler were performed, together with plasma BNP measurement 1 day before and 2 days after ASD closure. Before ASD closure, an age-dependent decrease was noted in left ventricular relaxation, assessed by early diastolic mitral annular velocity. ASD closure resulted in a decrease in early diastolic mitral annular velocity (from 14.7 to 12.3 cm/s, p <0.05) despite an increase in the left ventricular dimension (84% to 92% vs normal, p <0.05). These changes were associated with a parallel increase in BNP (17.9 to 48.4 pg/ml, p <0.05). Stepwise multivariate linear regression identified early diastolic mitral annular velocity before ASD closure and age as independent predictors of BNP levels after ASD closure (p <0.05). Consistent with this result, 2 patients with the lowest early diastolic mitral annular velocity developed exertional dyspnea after the procedure. In conclusion, our results indicate that TDI measurements could be useful to detect underlying diastolic dysfunction that can potentially cause heart failure after ASD closure and emphasize the importance of ASD closure at a young age before impairment of left ventricular relaxation.

Use of ultrasound in the ICU

Echography has developed as an indispensable tool in diagnosis and subsequent therapy in the critically ill. Although pulmonary and abdominal ultrasounds play a major role in their management, this article will discuss the advantages and indications of echocardiography in the intensive care unit (ICU). The assessment of morphological abnormalities, left or right ventricular malfunction, pulmonary arterial hypertension and valvular dysfunctions is a routine indication of echocardiography. Actually, besides contractility, several preload and even afterload indicators can also be assessed. In short, this bedside tool rapidly provides insight in the haemodynamics without invasive pressure estimations.

EXCEED: Exforge®-intensive control of hypertension to evaluate efficacy in diastolic dysfunction: study rationale, design, and participant characteristics

Background: Both diastolic dysfunction and increased vascular stiffness represent important measures of target-organ damage in hypertension. Whether intensive blood pressure (BP) control can further improve these measures remains unknown.

Methods: EXCEED is a prospective, randomized open-label blinded endpoint trial (PROBE) design, aiming to test the hypothesis that more aggressive BP lowering would result in greater improvement in diastolic function among patients with stage II hypertension, evidence of diastolic dysfunction and preserved systolic function (EF ≥ 50%). Patients were randomized to one of two treatment strategies, targeting systolic blood pressure (SBP) <140 mmHg or <130 mmHg using a combination of amlodipine/valsartan with additional antihypertensive medications as needed to achieve the prescribed targets. Diastolic function was assessed using Doppler tissue imaging of early diastolic velocity of lateral mitral annulus (E'), while vascular stiffness was assessed using radial augmentation index (RAI) derived from radial artery tonometry. The study primary endpoint will be the change in lateral E' velocity between baseline and 24 weeks.

Results: Two hundred and twenty eight patients (50% female) with mean age of (59.6±9.7) years and mean BP of (162±14/92±13 mmHg) were randomized equally to either treatment strategies. Left ventricular hypertrophy was present among <4% of the enrolled patients. Inspite diastolic function was impaired, baseline lateral E' velocity (7.6±1.2 cm/s) was not related to baseline SBP while baseline RAI was weakly related ( r = 0.2, p <0.01) to SBP even after adjustment to age, gender and heart rate.

Conclusion: EXCEED will determine whether intensive BP lowering will further improve diastolic dysfunction and vascular stiffness among patients with uncontrolled hypertension.

The role of echocardiography in the assessment of cardiac function in weightlessness-Our experience during parabolic flights

Parabolic flight (PF) elicits changes in hydrostatic pressure gradients, resulting in increase (at 0Gz) or decrease (at 1.8Gz) in cardiac preload. The magnitude of these changes on left ventricular (LV) and atrial (LA) volumes, as well as on myocardial velocities, strain and strain rates, is largely unknown. Using real-time 3D (RT3DE) and Doppler tissue echocardiographic imaging (DTI) during PF in normal subjects in standing position, we showed that both LV and LA volumes were decreased at 1.8Gz and increased at 0Gz by about 20% and 40%, respectively. Previous 2D or M-mode studies underestimated such changes. Also, preload dependence was confirmed for systolic and diastolic velocities, and peak systolic strain, while strain rates were preload independent, probably reflecting intrinsic myocardial properties. Low body negative pressure at -50mmHg applied during 0Gz was effective in restoring 1Gz levels. RT3DE and DTI during PF are feasible, allowing the evaluation of the cardiac function under different loading conditions.

Noninvasive evaluation of left ventricular noncompaction: what's new in 2009?

Significant interest in clinical practice as well as the medical literature exists regarding the presentation and outcome of children and adults with left-ventricular noncompaction (LVNC). The mainstay in the diagnosis of LVNC has been the anatomic definition of the ventricular myocardium by two-dimensional echocardiographic imaging. Although helpful, this approach lacks diagnostic precision and fails to evaluate the functional impact of this abnormal myocardial architecture on global and regional myocardial performance. This review will focus on the use of novel echocardiographic modalities of tissue Doppler, strain, and strain rate imaging to identify and characterize abnormalities of regional myocardial function in patients with LVNC.

Cardiac systolic and diastolic function during whole body heat stress

During a whole body heat stress, stroke volume is either maintained or slightly elevated despite reduced ventricular filling pressures and central blood volume, suggestive of improved cardiac diastolic and/or systolic function. Heat stress improves cardiac systolic and diastolic function in patients with congestive heart failure, although it remains unknown whether similar responses occur in healthy individuals, which is the hypothesis to be tested. Nine male volunteers underwent a whole body heat stress. Echocardiographic indexes of diastolic and systolic function were performed following a supine resting period, and again following an increase in internal temperature of approximately 1.0 degrees C via passive heat stress. Despite previous reports of heat stress-induced decreases in ventricular filling pressures and central blood volume, no changes in indexes of diastolic function were identified during heating [i.e., unchanged early diastolic mitral annular tissue velocity (E'), mitral inflow during the early diastolic phase (E), the E/E' ratio, and isovolumetric relaxation time]. Heat stress increased late diastolic septal (P = 0.03) and lateral (P = 0.01) mitral annular tissue velocities (A'), mitral inflow velocity during atrial contraction (P < 0.001), and the relative contribution of atrial contraction to left ventricular filling during diastole (P = 0.01), all indicative of improved atrial systolic function. Furthermore, indexes of ventricular systolic function were increased by heat stress [i.e., increased septal (P = 0.001) and lateral (P = 0.01) mitral annular systolic velocities and isovolumic acceleration at the septal (P = 0.03) and lateral (P < 0.001) mitral annulus]. These data are suggestive of improved atrial and ventricular systolic function by the heat stress. Together these data support previous findings, which used the less precise measure of ejection fraction, that heat stress improves indexes of systolic function, while diastolic function is maintained.

Impact of left ventricular volume/mass ratio on diastolic function

AIMS

To assess the impact of left ventricular (LV) volume/mass ratio on diastolic function parameters in subjects with dilated cardiomyopathy (DCM) or hypertrophic cardiomyopathy (HCM) and healthy controls.

METHODS AND RESULTS

We performed echocardiography in 44 healthy controls, 35 HCM subjects, 29 DCM subjects with narrow QRS complex (DCM-n), and 27 DCM subjects with wide QRS complex (DCM-w). Mitral annulus velocity (E(a)) and transmitral E-wave velocity were used to estimate time constant of isovolumic pressure decay (tau). LV flow propagation velocity (V(p)) and early intraventricular pressure gradient (IVPG) were derived from colour M-mode of LV inflow. We calculated LV twist and peak untwisting rate (UntwR) by speckle tracking. Mean LV volume/mass ratio was 0.34 +/- 0.09 mL/g in healthy controls, 0.15 +/- 0.06 mL/g in HCM, 0.6 +/- 0.2 mL/g in DCM-n, and 0.8 +/- 0.3 mL/g in DCM-w patients (P < 0.001 for all groups). Resting LV ejection fractions were 63 +/- 7, 64 +/- 8, 31 +/- 8, and 26 +/- 8%, respectively (P < 0.01 vs. controls for DCM groups). In a multivariate analysis, LV volume/mass ratio remained a strong independent predictor of V(p) (P < 0.001), IVPG (P = 0.009), and UntwR (P < 0.001) but not for E(a) (P = 0.25).

CONCLUSION

LV volume/mass ratio had influences on diastolic function parameters independent of intrinsic diastolic function and filling pressures. It should be considered when assessing patients suspected of LV diastolic dysfunction.

Transmitral flow velocity-contour variation after premature ventricular contractions: a novel test of the load-independent index of diastolic filling

The new echocardiography-based, load-independent index of diastolic filling (LIIDF) M was assessed using load-/shape-varying E-waves after premature ventricular contractions (PVCs). Twenty-six PVCs in 15 subjects from a preexisting simultaneous echocardiography-catheterization database were selected. Perturbed load-state beats, defined as the first two post-PVC E-waves, and steady-state E-waves, were subjected to conventional and model-based analysis. M, a dimensionless index, defined by the slope of the peak driving-force vs. peak (filling-opposing) resistive-force regression, was determined from steady-state E-waves alone, and from load-perturbed E-waves combined with a matched number of subsequent beats. Despite high degrees of E-wave shape variation, M derived from load-varying, perturbed beats and M derived from steady-state beats alone were indistinguishable. Because the peak driving-force vs. peak resistive-force relation determining M remains highly linear in the extended E-wave shape and load variation regime observed, we conclude that M is a robust LIIDF.