Study of Respiratory Variations of Mitral Valve Diastolic Flow in Hemodialysis Patients

The respiratory variations in mitral valve (MV) Doppler flow in hemodialysis (HD) patients have not been investigated and the normal echocardiographic value is used as a reference for HD patients. The present study evaluated the respiratory variation in MV Doppler flow in HD patients to determine if it has a unique pattern. In this prospective cohort study, echocardiography was performed before and 6 h after dialysis. The transmitral spectral Doppler E wave was measured during inspiratory and expiratory phases. The percent changes in the E wave were calculated pre- and post-dialysis. The means of the percent variation in the MV inspiratory and expiratory E wave pre- and post-dialysis were 56 ± 7% and 44 ± 1.1%, respectively, with a significant reduction after dialysis (P = .000). There was a significant positive correlation between post-dialysis ∆E wave % change and post-dialysis % change in weight (r = .318; P = .000). The respiratory changes in the MV E wave in HD patients were higher than the normal reference values. This marked variation could be explained by fluid overloading in HD patients.

Right Ventricular Strain Analysis By Tissue Tracking Cardiac Magnetic Resonance Imaging In Pediatric Patients With End-Stage Renal Disease

PURPOSE

To investigate right ventricular (RV) volume and mass by cardiac magnetic resonance (CMR) and the added value of tissue tracking strain analysis as markers of RV dysfunction in pediatric patients with end-stage renal disease (ESRD) and preserved RV ejection fraction.

MATERIALS AND METHODS

Twenty-five children with ESRD and preserved RVEF (>50%) and 10 healthy control children were enrolled. Tissue tracking CMR was used to assess Global Longitudinal, circumferential (GCS), and radial short and long axes (GRS SAX and GRS LAX) RV strains in the patients group compared with controls. Correlations between strain parameters and other CMR parameters and clinical biomarkers were assessed. Binary logistic regression was used to test the independence of cofounders and detect their significance.

RESULTS

RV end-diastolic volume and mass (RVMi) were significantly higher in patients (97.2±19.3 mL/m 2 and 26.6±7gr/m 2 ) than control (71±7.8 mL/m 2 and 11.9±2 gr/m 2 , P values 0.000). All RV global strain parameters were significantly impaired in patients compared with control (all P values <0.05). RV Global Longitudinal was significantly correlated to LVEF (r=-0.416, P =0.039), LVEDVi (r=0.481, P =0.015), LVMi (r=0.562, P =0.004), and systolic blood pressure index (r=0.586, P =0.002). RV GRS (LAX) was significantly correlated to LV GCS (r=-0.462, P =0.020) and LV GRS (SAX) (r=0.454, P =0.023). GRS (SAX) and GCS demonstrated the highest diagnostic accuracy (area under curve: 0.82 and 0.81) to detect strain impairment. Univariate binary logistic regression with patients versus control as dependent variables identified LVMi, RV end-diastolic volume, RVMi, weight, body surface area, RV GCS, RV GRS (LAX), RV GRS (SAX), LV GCS, and LV GRS (SAX) as significantly correlated to patients with ESRD. When adjusted to other cofounders in the multivariable model, only RVMi remained as an independent significant cofounder (Odds ratio:0.395, P =0.046).

CONCLUSION

RV global strain, volume, and mass by CMR are markers of RV dysfunction in ESRD pediatric patients with preserved RVEF.

Standardizing Blood Pressure Measurements in Pediatric Hemodialysis: a Collaborative Journey

PURPOSE OF REVIEW

This manuscript details the development and execution of a quality improvement (QI) initiative aimed at standardizing blood pressure (BP) measurement practices in pediatric hemodialysis (HD) units across a national dialysis collaborative.

RECENT FINDINGS

Although there are recommendations for the detection and treatment of hypertension in the pediatric population, currently there is no data or recommendations specific to the methodology of measuring blood pressure in a pediatric hemodialysis setting. In 2016, the Standardizing Care to Improve Outcomes in Pediatric End Stage Kidney Disease (SCOPE) Collaborative assembled a dedicated working group to thoroughly examine BP measurement practices across participating pediatric HD centers and, drawing from current research, to establish a standardized best practice for BP measurement in pediatric HD patients both in-center and at home. Employing QI methodology, the working group devised a standardized "BP Bundle" and implemented it throughout the SCOPE Collaborative. This work led to successful practice improvement by establishing a consistent approach to BP measurement in pediatric HD patients cared for in SCOPE centers. With a standard best practice now in place and over 85% compliance with the BP Bundle across the SCOPE Collaborative, researchers and healthcare professionals can more accurately study and ultimately enhance the cardiovascular health of pediatric HD patients.

A new technique for the detection of dry weight in hemodialysis patients: Estimated pulmonary capillary wedge pressure. A tissue Doppler imaging study

BACKGROUND AND OBJECTIVE

Fluid overload is an important factor of morbidity and mortality in hemodialysis patients. Today correct determination of dry weight (DW) remains an important issue of hemodialysis practice. Within this context, it is subjected to new method searching. The objective of this study was to calculate estimated pulmonary capillary wedge pressure (ePCWP) with Tissue Doppler Imaging (TDI) in hemodialysis patients and to evaluate its correlation with the other volume markers and to evaluate whether it can be a new method for detection of DW.

MATERIALS AND METHODS

Echocardiographic, hemodynamic, and biochemical volume markers of 41 hemodialysis patients were evaluated in the pre- and post-dialysis periods. Patients were divided into two groups based on ePCWP values (Group 1 ePCWP<20mmHg, Group 2 ePCWP>20mmHg).

RESULTS

In the pre-dialysis period; parameters related to volume load including ePCWP, systolic blood pressure, mean arterial pressure, pulse pressure, left atrial diameter, left atrial volume, E/é, ratio and E/V_p ratio were statistically significantly higher in Group2 compared to Group1. On the other hand, strong correlations were found between pre-dialysis ePCWP and systolic blood pressure, mean arterial pressure, pulse pressure, NT-ProBNP, left atrial diameter, E/é ratio and E/V_p ratio.

CONCLUSIONS

Strong correlations found between ePCWP which was calculated with TDI and the other volume markers both in pre-dialysis and post-dialysis periods. These findings can provide a significant contribution to routine evaluating of DW in hemodialysis patients. From this aspect, the prediction of ePCWP with TDI can be a new practical and reproducible method for the determination of DW.

Evaluation of Asymmetric Dimethylarginine Serum Level and Left Ventricular Function by 2D Speckle Tracking Echocardiography in Children on Regular Hemodialysis

Cardiovascular disease is the leading cause of morbidity and mortality in children with chronic kidney disease. Asymmetric dimethylarginine (ADMA) is thought to be related to chronic kidney disease patients' adverse cardiovascular effects. Our study is to assess ADMA concentrations in children on hemodialysis (HD) as a marker of cardiovascular risk and detect the relation to the left ventricular (LV) function by traditional and speckled tracking echo. Forty children with end-stage renal disease on regular HD were enrolled in the study and selected from the nephrology HD unit of Al-Zahraa Hospital, Al-Azhar University. Another group of 40 healthy children matches age and sex with the patient's group as a control. ADMA serum level, traditional echo, and tissue Doppler imaging spackled tracking were performed to assess: LV functions for both groups in the same line with the routine laboratory investigations. Moreover, bioimpedance was assessed after the HD session. Children on regular HD have a significantly higher (ADMA) serum level compared to their controls; the median is (72.5 ng/mL) and (25 ng/mL), respectively (P = 0.001) and a significant increase in high-sensitivity C-reactive protein and the median is (3.6 ng/mL) and (2.5 ng/mL), respectively (P = 0.001). Moreover, conventional echo detects 27 (67.5%) patients out of 40 had an impaired LV function; meanwhile, 33 (82.5%) had a global LV strain (LV GLS) detected by 2D (Speckle echo), a negative correlation between LV ejection fraction with serum (urea, cholesterol, and triglyceride) and a positive correlation between ADMA and LV systolic diameter. LV GLS (Speckle echo) is negatively correlated with LV end-diastolic diameter, LV end-systolic diameter and positively correlated with LV inter ventricular septum in diastole and reduced average systolic velocity (ml). The sensitivity and specificity of (ADMA), high-sensitivity C-reactive protein (hs-CRP), traditional, and Speckle echo for early left ventricular (LV) dysfunction were 92.50, 92, and 67.50, 97 and 67.50, 90.00, and 80.00, 92, respectively. An ADMA emerges as a sensitive and specific marker for early LV dysfunction in children on hemodialysis (HD); drugs targeting ADMA isessential in the future direction after clinical approval, to avoid early LV changes, furthermore (Speckle echo) is superior to the traditional echo for early detection of LV changes in chronic kidney disease (CKD) children.

Exercise Systolic Reserve and Exercise Pulmonary Hypertension Improve Diagnosis of Heart Failure With Preserved Ejection Fraction

Aims

Diastolic stress testing (DST) is recommended to confirm heart failure with preserved ejection fraction (HFpEF) in patients with exertional dyspnea, but current algorithms do not detect all patients. We aimed to identify additional echocardiographic markers of elevated pulmonary arterial wedge pressure during exercise (exPAWP) in patients referred for DST.

Methods and Results

We identified candidate parameters in 22 patients referred for exercise right heart catheterization with simultaneous echocardiography. Elevated exPAWP (≥25 mmHg) was present in 14 patients, and was best identified by peak septal systolic annular velocity <9.5 cm/s [exS', area under the receiver operating characteristic curve (AUC) 0.97, 95% confidence interval 0.92–1.0] and mean pulmonary artery pressure/cardiac output slope ≥3.2 mmHg/L [mPAP/CO, AUC 0.88 (0.72–1.0)]. We propose a decision tree to identify patients with elevated exPAWP. Applying this decision tree to 326 patients in an independent non-invasive DST cohort showed that patients labeled as “high probability of HFpEF” (n = 85) had reduced peak oxygen uptake [13.0 (10.7–15.1) mL/kg/min, p < 0.001 vs. intermediate/low probability], high H2FPEF score [53 (40–72) %, p < 0.001 vs. intermediate/low probability], and typical clinical characteristics. The diagnostic yield of DST increased from 11% using exercise E/e', to 62% using the decision tree.

Conclusion

In DST for suspected HFpEF, exS' was the most accurate echocardiographic parameter to identify elevated PAWP. We propose a decision tree including exS' and mPAP/CO for interpretation of DST. Application of this decision tree revealed typical HFpEF characteristics in patients labeled as high probability of HFpEF, and substantially reduced the number of inconclusive results.

Consensus Defined Diastolic Dysfunction and Cardiac Postoperative Morbidity Score: A Prospective Observational Study

Diastolic dysfunction is associated with major adverse outcomes following cardiac surgery. We hypothesized that multisystem endpoints of morbidity would be higher in patients with diastolic dysfunction. A total of 142 patients undergoing cardiac surgical procedures with cardiopulmonary bypass were included in the study. Intraoperative assessments of diastolic function according to the 2016 American Society of Echocardiography and European Association of Cardiovascular Imaging guidelines using transesophageal echocardiography were performed. Cardiac Postoperative Morbidity Score (CPOMS) on days 3, 5, 8, and 15; length of stay in ICU and hospital; duration of intubation; incidence of new atrial fibrillation; 30-day major adverse cardiac and cerebrovascular events were recorded. Diastolic function was determinable in 96.7% of the dataset pre and poststernotomy assessment (n = 240). Diastolic dysfunction was present in 70.9% (n = 88) of measurements before sternotomy and 75% (n = 93) after sternal closure. Diastolic dysfunction at either stage was associated with greater CPOMS on D5 (p = 0.009) and D8 (p = 0.009), with CPOMS scores 1.24 (p = 0.01) higher than in patients with normal function. Diastolic dysfunction was also associated with longer durations of intubation (p = 0.001), ICU length of stay (p = 0.019), and new postoperative atrial fibrillation (p = 0.016, OR (95% CI) = 4.50 (1.22–25.17)). We were able to apply the updated ASE/EACVI guidelines and grade diastolic dysfunction in the majority of patients. Any grade of diastolic dysfunction was associated with greater all-cause morbidity, compared with patients with normal diastolic function.

A new technique for the detection of dry weight in hemodialysis patients: Estimated pulmonary capillary wedge pressure. A tissue Doppler imaging study

BACKGROUND AND OBJECTIVE

Fluid overload is an important factor of morbidity and mortality in hemodialysis patients. Today correct determination of dry weight (DW) remains an important issue of hemodialysis practice. Within this context, it is subjected to new method searching. The objective of this study was to calculate estimated pulmonary capillary wedge pressure (ePCWP) with Tissue Doppler Imaging (TDI) in hemodialysis patients and to evaluate its correlation with the other volume markers and to evaluate whether it can be a new method for detection of DW.

MATERIALS AND METHODS

Echocardiographic, hemodynamic, and biochemical volume markers of 41 hemodialysis patients were evaluated in the pre- and post-dialysis periods. Patients were divided into two groups based on ePCWP values (Group 1 ePCWP<20mmHg, Group 2 ePCWP>20mmHg).

RESULTS

In the pre-dialysis period; parameters related to volume load including ePCWP, systolic blood pressure, mean arterial pressure, pulse pressure, left atrial diameter, left atrial volume, E/é, ratio and E/Vp ratio were statistically significantly higher in Group2 compared to Group1. On the other hand, strong correlations were found between pre-dialysis ePCWP and systolic blood pressure, mean arterial pressure, pulse pressure, NT-ProBNP, left atrial diameter, E/é ratio and E/Vp ratio.

CONCLUSIONS

Strong correlations found between ePCWP which was calculated with TDI and the other volume markers both in pre-dialysis and post-dialysis periods. These findings can provide a significant contribution to routine evaluating of DW in hemodialysis patients. From this aspect, the prediction of ePCWP with TDI can be a new practical and reproducible method for the determination of DW.

Left Ventricular Mass Assessment by 1- and 2-Dimensional Echocardiographic Methods in Hemodialysis Patients: Changes in Left Ventricular Volume Using Echocardiography Before and After a Hemodialysis Session

RATIONALE & OBJECTIVE

Left ventricular (LV) mass (LVM) is a predictor of cardiovascular morbidity and mortality and commonly calculated using 1-dimensional (1D) echocardiographic methods. These methods are vulnerable to small measurement errors and LVM may wrongly change according to changes in LV volume (LVV). Less commonly used 2-dimensional (2D) methods can accommodate to the changes in LVV and may be a better alternative among patients receiving hemodialysis (HD) with large fluid fluctuations.

STUDY DESIGN

Observational study.

SETTING & PARTICIPANTS

Patients with end-stage kidney disease receiving HD.

EXPOSURE

One HD session.

ANALYTICAL APPROACH

Transthoracic echocardiography was performed right before and after HD. LVM was calculated using 1D (Devereux, Penn, and Teichholz) and 2D methods (truncated ellipsoid and area-length).

OUTCOMES

Significant differences in LVM after HD.

RESULTS

We compared dimensions, LVV and LVM, in 53 patients (mean age, 63 ± 15 years; 66% men). For each 1-L increase in ultrafiltration volume (UFV), LV internal diameter decreased 1.1 mm (95% CI, 0.5-1.7 mm; P = 0.001). Patients were divided into 2 groups by the median UFV of 1.6 L. Patients with UFV > 1.6 L had significant smaller LVV and LV internal diameter after HD. LVM calculated using 1D methods decreased according to changes in LVV. Conversely, LVM calculated using 2D methods was not significantly different after HD. No significant change in differences between diastolic - systolic myocardial thickness or LVM as assessed using 1D and 2D methods was observed before and after HD, indicating that LVM remained constant despite HD.

LIMITATIONS

We did not use contrast enhancement, 3-dimensional methods, or cardiac magnetic resonance.

CONCLUSIONS

LVM calculated using 2D methods, truncated ellipsoid and area-length, is less affected by fluctuations in fluid and LVV, in contrast to 1D methods. Complementary LVM calculation using 2D methods is encouraged, especially in patients with large fluid fluctuations in which increased LVM using a 1D method has been detected.

Changes of cardiac functions after hemodialysis session in pediatric patients with end-stage renal disease: conventional echocardiography and two-dimensional speckle tracking study

BACKGROUND

Although acute effects of hemodialysis (HD) on cardiac functions in end-stage renal disease (ESRD) have been studied frequently in adults, limited data are available in pediatric age. Therefore, this work elucidates the acute impact of HD on cardiac functions using conventional echocardiography and two-dimensional (2D) speckle tracking in ESRD pediatric patients.

METHODS

Between June 2018 and April 2019, 40 ESRD pediatric subjects on chronic HD were prospectively recruited. All patients were subjected to history taking and baseline laboratory tests. Anthropometric measures, heart rate, blood pressure, and bioimpedance were assessed before and after HD session. Moreover, conventional echocardiography including M.mode and Doppler parameters for valves, as well as left ventricle (LV) 2D speckle tracking were performed pre- and post-dialysis session.

RESULTS

The included patients mean age was 12.9 ± 2.9 years, and males were 24 (60%). Significant reductions in body weight and blood pressure were noted after sessions. Post-dialysis LV and left atrial diameters, as well as left atrium to aortic diameter ratio, were lower. Nevertheless, conventional echocardiography-derived LV ejection fraction (EF), and fractional shortening were not significantly changed. Doppler-derived E/A ratio of mitral and tricuspid valves were lower post-dialysis. Global longitudinal strain (GLS) for LV was significantly reduced after dialysis (- 20.31 ± 3.58%, - 17.17 ± 3.40% vs, P < 0.0001), and global circumferential strain (GCS) was lower post-dialysis in comparison to pre-dialysis (- 21.37 ± 6.46% vs - 17.74 ± 6.16%, P < 0.0001). The speckle tracking-derived EF was significantly lower post-dialysis (57.58 ± 6.94 vs 53.64 ± 10.72, P = 0.018). All myocardial segments longitudinal and circumferential strains decreased significantly after dialysis.

CONCLUSIONS

Post-hemodialysis significant decline in left ventricular EF as well as global and segmental strains can be detected in ESRD pediatric patients using 2D speckle tracking, despite the nonsignificant changes in systolic functions derived from conventional echocardiography. This is considered additional evidence of HD deleterious effect on myocardial functions, particularly in the pediatric age.

Right Ventricular Analysis Using Real-time Three-dimensional Echocardiography for Preload Dependency

BACKGROUND

The importance of the right ventricle (RV) has been increasingly recognized, and accurate RV measurement has become necessary. However, assessment of the RV with two-dimensional (2D) echocardiography has several limitations. As the development of novel methods for RV measurement continues, we can expect more accordant values related to RV geometry.

METHODS

Fifty-eight subjects who were examined by transthoracic echocardiography (TTE) immediately before and after hemodialysis (HD) were enrolled. Real-time, full-volume, three-dimensional (3D) echocardiographic images were acquired and analyzed using dedicated software. Conventional RV parameters for RV size and function were measured for comparison with pre-HD and post-HD values by both 2D-TTE and 3D-TTE.

RESULTS

3D RV volumes and ejection fractions were significantly decreased after HD. The values of the 3D image-derived RV dimensions, tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and longitudinal strain were also affected by acute preload changes (TAPSE pre-HD: 22.4 ± 4.0 mm, post-HD: 19.0 ± 4.2 mm, p < 0.001; FAC pre-HD: 49.6% ± 5.9%, post-HD: 46.4% ± 5.5%, p < 0.001; septal longitudinal strain pre-HD: -20.1% ± 3.7%, post-HD: -16.8% ± 3.8%, p < 0.001). With the exception of FAC, most 2D RV parameters were well correlated with the 3D values.

CONCLUSIONS

Various parameters representing RV anatomy and function were acquired easily and more accurately from 3D echocardiographic images than from 2D images but were affected by acute preload changes. 3D TTE could be a new modality for assessing RV function and size, but each value from 3D TTE should be interpreted with caution while considering the loading condition of the patients.

Pharmacodynamic Analysis of the Influence of Propofol on Left Ventricular Long-Axis Systolic Performance in Cardiac Surgical Patients

BACKGROUND

Propofol induced a decline in the left ventricular (LV) systolic performance in non-cardiac surgery. We tested the hypothesis that propofol decreased the LV contractile function by dose dependent manner in cardiac surgery patients.

METHODS

Anesthesia was maintained with target-controlled infusions of propofol and remifentanil in cardiac surgery patients. With a fixed effect-site concentration (Ce) of remifentanil (20 ng/mL) after sternotomy, the Ce of propofol was adjusted to maintain a Bispectral index of 40-60 (Ce1). Mitral annular Doppler tissue image tracings and other echocardiographic variables, including end-diastolic and end-systolic volumes, stroke volume, and mitral inflow pulse wave Doppler profile at Ce1, were recorded using transesophageal echocardiography. Echocardiographic recordings were repeated after the Ce-values of propofol were doubled and tripled at 10-minute intervals (defined as Ce2 and Ce3, respectively). Serial changes in echocardiographic variables for each Ce of propofol were assessed using generalized linear mixed effect modeling. The pharmacodynamic relationship between the Ce of propofol and peak systolic mitral annular velocity (Sm) was analyzed by logistic regression using non-linear mixed effect modeling (NONMEM).

RESULTS

Means of Ce1, Ce2, and Ce3 were 0.8, 1.6, and 2.4 μg/mL, respectively, and their means of Sm (95% confidence interval) were 9.7 (9.3-10.2), 8.7 (8.2-9.1), and 7.5 cm/sec (7.0-8.0), respectively (P < 0.01). Ce values of propofol and Sm showed a significant inter-correlation and predictability (intercept, 10.8; slope-1.0 in generalized mixed linear modeling; P < 0.01). Ce values producing 10% and 20% decline of Sm with 50%-probability were 1.4 and 2.1 μ/mL, respectively.

CONCLUSION

Propofol reduces LV systolic long-axis performance in a dose-dependent manner.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01826149.

Insights into the mechanism of paradoxical low-flow, low-pressure gradient severe aortic stenosis: association with reduced O2 consumption by the whole body

The mechanism of reduced stroke volume index (SVi) in paradoxical low-flow, low-pressure gradient (PLFLPG) aortic stenosis (AS) remains unclarified. Guyton et al. ( 21 ) demonstrated that SVi is determined by whole body O₂ consumption (V̇o₂) in many subjects, including patients with heart disease. We hypothesized that reduced SVi in PLFLPG AS is associated with reduced V̇o₂ by the whole body. This study investigated the relationship between V̇o₂, SVi, and AS severity in patients with AS to examine the association between reduced V̇o₂ and PLFLPG AS. In 59 patients (24 men and 35 women, mean age: 78 ± 7 yr old) with severe AS, SVi, AS severity, and type were evaluated by echocardiography, and V̇o₂ was measured by the fraction of O₂ in expired gases. SVi and V̇o₂ were significantly decreased in 20 patients with PLFLPG AS compared with 39 patients with non-PLFLPG AS (30 ± 4 vs. 41 ± 7 ml/m² and 2.4 ± 0.5 vs. 3.0 ± 0.5 ml·min^-1·kg^-1, respectively, P < 0.01). The SVi-to-V̇o₂ ratio was not different between the two groups (13.1 ± 2.6 vs. 13.6 ± 2.1, not significant). SVi was independently correlated with V̇o₂ ( r = 0.74, P < 0.01) but not with the aortic valve area index. Categorized PLFLPG AS was also significantly associated with reduced V̇o₂ ( P < 0.001). PLFLPG AS is associated with reduced V̇o₂ by the whole body, which may offer insights into the mechanism of PLFLPG AS. NEW & NOTEWORTHY Paradoxical low-flow, low-pressure gradient severe aortic stenosis (PLFLPG AS) is an important and problematic subtype, and its central pathophysiology with reduced stroke volume is yet to be clarified. We hypothesized and subsequently clarified that reduced stroke volume in PLFLPG AS is associated with reduced O₂ consumption by the whole body. This study suggests important insights into the mechanism of PLFLPG AS and may further promote studies to investigate further mechanisms and novel treatment.

The Ebb and Flow of Echocardiographic Cardiac Function Parameters in Relationship to Hemodialysis Treatment in Patients with ESRD

Cardiovascular disease is the leading cause of mortality in patients receiving hemodialysis. Cardiovascular events in these patients demonstrate a day-of-week pattern; i.e., they occur more commonly during the last day of the long interdialytic interval and the first session of the week. The hemodialysis process causes acute decreases in cardiac chamber size and pulmonary circulation loading and acute diastolic dysfunction, possibly through myocardial stunning and other non-myocardial-related mechanisms; systolic function, in contrast, is largely unchanged. During interdialytic intervals volume overload, acid-base, and electrolyte shifts, as well as arterial and myocardial wall changes, result in dilatation of right cardiac chambers and pulmonary circulation overload. Recent studies suggest that these alterations are more extended during the long interdialytic interval or the first dialysis session of the week and are associated with excess volume overload or removal, respectively, thus adding a mechanism for the day-of-week pattern of mortality in patients receiving hemodialysis. This review summarizes the existing data from echocardiographic studies of cardiac morphology and function during the hemodialysis session, as well as during the interdialytic intervals.

Haemodialysis acutely deteriorates left and right diastolic function and myocardial performance: an effect related to high ultrafiltration volumes?

Background

The effect of acute preload reduction during haemodialysis on left ventricle (LV) and right ventricle (RV) function is not well understood. This study aimed to evaluate acute changes in novel echocardiographic and tissue Doppler-derived indices of LV and RV function during the first and a standard weekly dialysis session and to examine the possible effect of acute intradialytic volume changes in LV and RV diastolic function and pulmonary circulation loading.

Methods

Forty-one adult patients receiving standard thrice-weekly haemodialysis participated in this study. Two-dimensional echocardiographic and tissue Doppler imaging (TDI) studies were performed with a standard cardiac ultrasound device (Vivid 7 or Vivid e, GE, Horton, Norway) shortly before and after the first weekly and a standard dialysis session. Multiple linear regression analysis was applied to assess the effect of volume changes on peak early mitral (E) and tricuspid (E RV) velocities changes.

Results

Significant reductions from pre- to post-haemodialysis were noted in body weight and systolic blood pressure. Post-haemodialysis left and right atrial, LV and RV sizing echocardiographic parameters were lower. LV systolic function, represented by LV ejection fraction, cardiac output and mean peak systolic LV and RV velocities at the annulus level, was unchanged. Diastolic function indices such as E (first session: 0.96 ± 0.28 versus 0.75 ± 0.27 m/s, P < 0.001; standard session: 0.89 ± 0.24 versus 0.78 ± 0.29, P < 0.001) and E RV (first session: 0.89 ± 0.26 versus 0.67 ± 0.25 m/s, P < 0.001; standard session: 0.86 ± 0.24 versus 0.77 ± 0.31, P < 0.001), E/A LV ratio, TDI peak early mitral (E') velocity and E'/A' RV ratio were reduced after haemodialysis. Pulmonary circulation loading, represented by RV systolic pressure, was significantly improved. In multiple regression model analysis, intradialytic weight loss was independently associated with changes in E [β = 0.042 (95% CI 0.018-0.066)] and E RV [β = 0.084 (95% CI 0.057-0.110)].

Conclusions

This study shows that haemodialysis deteriorates cardiac diastolic function indices and improves pulmonary circulation loading, while systolic function remains unchanged. High intradialytic volume removal may affect cardiac diastolic function.

Left ventricular dysfunction by conventional and tissue Doppler echocardiography in pediatric hemodialysis patients: relation with plasma brain natriuretic peptide levels

INTRODUCTION

Tissue Doppler imaging (TDI) is a relatively new echocardiography method in children with chronic kidney disease (CKD). The aims of this study were to evaluate left ventricular (LV) diastolic function in pediatric CKD patients using conventional pulsed-wave Doppler echocardiography (cPWD) and TDI methods and correlate them with BNP levels.

MATERIAL AND METHODS

Thirty children on regular hemodialysis (HD) were included. Left ventricular systolic and diastolic indices and BNP levels were measured immediately before and after HD.

RESULTS

After HD, LV and left atrium diameters were significantly decreased (p < 0.001 and p < 0.001, respectively). Transmitral E velocity and E/A ratio decreased (p < 0.001 and p < 0.001, respectively). Also, there were significant decreases in the early diastolic velocity E' of LV wall, septal wall, and anterior wall (p = 0.001, p = 0.004 and p < 0.001, respectively). Mean E/E' ratio and ratios of septal and lateral walls were decreased significantly (p = 0.004, p = 0.002 and p = 0.017, respectively). BNP levels decreased significantly during HD when comparing concentrations before and after HD (p < 0.001). BNP strongly correlated with LV diastolic function indices (before HD: mean E/E' (r = 0.401, p = 0.028), lateral E/E" (r = 0.291, p = 0.025), septal E'(r = -0.398, p = 0.029), lateral wall E' (r = -0.452, p = 0.012) and mean E' (r = -0.469, p = 0.009), after HD: mean E/E' (r = 0.38, p = 0.038) and lateral E/E" (r = 0.474, p = 0.008) and lateral wall E' (r = -0.270, p = 0.037)).

CONCLUSIONS

The cPWD and TDI-derived LV indices are influenced by HD. The diagnostic utility of BNP in the presence of deteriorating renal function may be compromised to some extent.

Isoflurane's Effect on Intraoperative Systolic Left Ventricular Performance in Cardiac Valve Surgery Patients

BACKGROUND

Isoflurane, a common anesthetic for cardiac surgery, reduced myocardial contractility in many experimental studies, few studies have determined isoflurane's direct impact on the left ventricular (LV) contractile function during cardiac surgery. We determined whether isoflurane dose-dependently reduces the peak systolic velocity of the lateral mitral annulus in tissue Doppler imaging (S') in patients undergoing cardiac surgery.

METHODS

During isoflurane-supplemented remifentanil-based anesthesia for patients undergoing cardiac surgery with preoperative LV ejection fraction greater than 50% (n = 20), we analyzed the changes of S' at each isoflurane dose increment (1.0, 1.5, and 2.0 minimum alveolar concentration [MAC]: T1, T2, and T3, respectively) with a fixed remifentanil dosage (1.0 μg/min/kg) by using transesophageal echocardiography.

RESULTS

Mean S' values (95% confidence interval [CI]) at T1, T2, and T3 were 10.5 (8.8-12.2), 9.5 (8.3-10.8), and 8.4 (7.3-9.5) cm/s, respectively (P < 0.001 in multivariate analysis of variance test). Their mean differences at T1 vs. T2, T2 vs. T3, and T1 vs. T3 were -1.0 (-1.6, -0.3), -1.1 (-1.7, -0.6), and -2.1 (-3.1, -1.1) cm/s, respectively. Phenylephrine infusion rates were significantly increased (0.26, 0.22, and 0.47 μg/kg/min at T1, T2, and T3, respectively, P < 0.001).

CONCLUSION

Isoflurane increments (1.0-2.0 MAC) dose-dependently reduced LV systolic long-axis performance during cardiac surgeries with a preserved preoperative systolic function.

Two-dimensional-strain echocardiography in intensive care unit patients: A prospective, observational study

PURPOSE

Two-dimensional-strain echocardiography (2D-strain) is a promising technique for the early detection of myocardial dysfunction. Our study was aimed to assess its feasibility in the intensive care unit (ICU). Our secondary goal was to determine if 2D-strain could predict the patient's outcome.

METHODS

Conventional echocardiography and 2D-strain were performed on 64 consecutive patients admitted to our ICU. Using 2D-strain, the longitudinal deformation of the left ventricle was assessed. Feasibility of 2D-strain, diagnosis performance, and 28-day mortality prediction were determined.

RESULTS

2D-strain measurements could be performed in 77% of our patients. All 2D-strain variables related to ventricular performance were significantly impaired in the patients who died compared with those who survived. Strain global medium was the only independent echocardiographic variable predictor of 28-day mortality rate (odds ratio 0.60; 95% confidence interval 0.43-0.80, p = 0.002).

CONCLUSIONS

2D-strain measurement is feasible in ICU patients, enabling identifying early left ventricle dysfunction. Strain global medium is an independent predictor of 28-day mortality. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:368-374, 2016.

MicroRNAs as Biomarkers for Acute Atrial Remodeling in Marathon Runners (The miRathon Study--A Sub-Study of the Munich Marathon Study)

Introduction

Physical activity is beneficial for individual health, but endurance sport is associated with the development of arrhythmias like atrial fibrillation. The underlying mechanisms leading to this increased risk are still not fully understood. MicroRNAs are important mediators of proarrhythmogenic remodeling and have potential value as biomarkers in cardiovascular diseases. Therefore, the objective of our study was to determine the value of circulating microRNAs as potential biomarkers for atrial remodeling in marathon runners (miRathon study).

Methods

30 marathon runners were recruited into our study and were divided into two age-matched groups depending on the training status: elite (ER, ≥55 km/week, n = 15) and non-elite runners (NER, ≤40 km/week, n = 15). All runners participated in a 10 week training program before the marathon. MiRNA plasma levels were measured at 4 time points: at baseline (V1), after a 10 week training period (V2), immediately after the marathon (V3) and 24h later (V4). Additionally, we obtained clinical data including serum chemistry and echocardiography at each time point.

Results

MiRNA plasma levels were similar in both groups over time with more pronounced changes in ER. After the marathon miR-30a plasma levels increased significantly in both groups. MiR-1 and miR-133a plasma levels also increased but showed significant changes in ER only. 24h after the marathon plasma levels returned to baseline. MiR-26a decreased significantly after the marathon in elite runners only and miR-29b showed a non-significant decrease over time in both groups. In ER miRNA plasma levels showed a significant correlation with LA diameter, in NER miRNA plasma levels did not correlate with echocardiographic parameters.

Conclusion

MiRNAs were differentially expressed in the plasma of marathon runners with more pronounced changes in ER. Plasma levels in ER correlate with left atrial diameter suggesting that circulating miRNAs could potentially serve as biomarkers of atrial remodeling in athletes.

Paradoxical increase in E/e' ratio after treatment of heart failure in two patients with preserved ejection fraction

We report an increase in E/e' ratio after treatment of heart failure (HF) in two patients. In case 1, the E/e' ratio increased from 15 to 18 after treatment of HF. In case 2, the E/e' ratio also increased from 24 to 35. Although a high E/e' ratio suggests high pulmonary artery wedge pressure and worsening HF, the ratio may increase after improvement of HF.In the present cases of diastolic dysfunction, the high E wave did not change, but the e' wave decreased relatively. This report may suggest difficulty in evaluating hemodynamic status based on the E/e' ratio in patients with diastolic dysfunction.

Echocardiographic assessment of right ventricular functions in nondiabetic normotensive hemodialysis patients

PURPOSE

Heart is affected structurally and functionally in end-stage renal disease (ESRD). However, the data available about adverse effects of ESRD on right ventricle (RV) is scarce. We aimed to evaluate echocardiographic parameters of RV in nondiabetic, normotensive patients with ESRD undergoing hemodialysis (HD).

METHODS

A total of 45 (24 women; mean age 52.4 ± 12.4 years) consecutive nondiabetic, normotensive patients with ESRD undergoing HD and 39 healthy age and sex-matched control subjects (22 women; mean age 50.3 ± 6.6 years) were enrolled in the study. M-mode and two dimensional images, color, pulsed and continuous wave Doppler, and tissue Doppler measurements were acquired from all subjects. Echocardiographic evaluation was performed in the days between HD dates of the patients.

RESULTS

RV fractional area change, tricuspid annular plane systolic excursion, tricuspid E velocity, E/A ratio, tricuspid annular E´ velocity, and E´/A´ ratio were lower in patients than controls (p < 0.001, p = 0.003, p = 0.007, p = 0.005, p < 0.001, and p = 0.034, respectively). However, RV diastolic area, RV myocardial performance index, E/E´ ratio, and mean and systolic pulmonary artery pressure were higher in patients than controls (p < 0.001, p = 0.007, p = 0.005, p < 0.001, p = 0.006, respectively).

CONCLUSIONS

RV systolic and diastolic functions of nondiabetic, normotensive HD patients are deteriorated as compared to healthy controls.

Comparing right ventricular function and pulmonary artery pressure before and shortly after hemodialysis in patients with end-stage renal disease

BACKGROUND

Early screening and diagnosis of right ventricular (RV) dysfunction and pulmonary artery hypertension is vital in patients with end-stage renal disease (ESRD) because of its relation to patients' survival. The present study is aimed to address and compare RV function parameters and pulmonary artery pressure (PAP) before and shortly after hemodialysis in patients with ESRD.

MATERIALS AND METHODS

This quasi-experimental study performed at Alzahra Hospital in Isfahan in 2014, 40 consecutive patients with ESRD that referred to hemodialysis ward were assessed by M-mode echocardiography and tissue Doppler imaging before and 30 min after completing hemodialysis to assess RV function parameters and PAP.

RESULTS

Following hemodialysis, mean body weight, both systolic, and diastolic blood pressures (BPs) and also mean systolic PAP significantly decreased, while tricuspid annulus plane systolic excursion (TAPSE), RV fractional area change (RVFAC) significantly increased 30 min after hemodialysis compared with before this procedure. However, systolic myocardial remained unchanged. Changes in body weight after dialysis was adversely associated with patients' age and duration of dialysis. Moreover, change in PAP was positively associated with the level of serum creatinine.

CONCLUSION

Early reduction in body weight and BP, as well as improvement in RV function, and PAP is predictable shortly after starting hemodialysis in patients with ESRD. We found that RVFAC and TAPSE values were dependent on preload, but RV S' velocity was load independent. Change in body weight is predicted more in older patients and those who undergoing prolonged hemodialysis. Change in PAP is strongly affected by the severity of renal failure, but RV function may not be influenced by age or duration of dialysis.

Relative Importance of Aortic Stiffness and Volume as Predictors of Treatment-Induced Improvement in Left Ventricular Mass Index in Dialysis

This study aimed to explore the relative contribution of aortic stiffness and volume in treatment-induced change of left ventricular mass in dialysis. Hypertension in Hemodialysis Patients Treated with Atenolol or Lisinopril trial compared the effect of lisinopril versus atenolol in reducing left ventricular mass index; 179 patients with echo measurements of aortic pulse wave velocity and left ventricular mass at baseline were included. In unadjusted analysis, overall reductions of 26.24 g/m² (95% CI: -49.20, -3.29) and 35.67 g/m² (95% CI: -63.70, -7.64) in left ventricular mass index were noted from baseline to 6 and 12 months respectively. Volume control emerged as an important determinant of regression of left ventricular mass index due to the following reasons: (i) additional control for change in ambulatory systolic blood pressure mitigated the reduction in left ventricular mass index in the statistical model above [6-month visit: -18.6 g/m² (95% CI: -43.7, 6.5); 12-month visit: -22.1 g/m² (95% CI: -52.2, 8.0)] (ii) regression of left ventricular hypertrophy was primarily due to reduction in left ventricular chamber and not wall thickness and (iii) adjustment for inferior vena cava diameter (as a proxy for volume) removed the effect of time on left ventricular mass index reduction [6-month visit: -6.6 g/m² (95% CI: (-41.6, 28.4); 12-month visit: 0.6 g/m² (95% CI: -39.5, 40.7)]. In contrast, aortic pulse wave velocity was neither a determinant of baseline left ventricular mass index nor predictor of its reduction. Among dialysis patients, ambulatory systolic pressure, a proxy for volume expansion, but not aortic stiffness is more important predictor of reduction in left ventricular mass index. Improving blood pressure control via adequate volume management appears as an effective strategy to improve left ventricular hypertrophy in dialysis.

Tissue Doppler and strain imaging of left ventricle in Beagle dogs with iatrogenic hypercortisolism

Changes in radial and longitudinal left ventricular (LV) function were investigated in beagles with iatrogenic hypercortisolism. A total of 11 normal dogs were used, and 2 mg/kg prednisone was administered per oral q12 h for 28 days to 7 out of 11 dogs to induce iatrogenic hypercortisolism. Body weight, blood pressure, conventional echocardiography and tissue Doppler imaging (TDI) of normal and iatrogenic hypercortisolism groups were conducted. The myocardial wall velocity of the LV was measured using color TDI and myocardial deformation was determined by the strain and strain rate. Conventional echocardiography revealed that the diastolic LV free wall and interventricular septum in the hypercortisolism group were thickened relative to those in the normal group. The peak early diastolic myocardial velocity and early to late diastolic myocardial velocity ratio of TDI in the hypercortisolism group were significantly lower than those in the normal group. The strain values in the hypercortisolism group were significantly lower than those in the normal group, particularly for longitudinal wall motion. The lower values of myocardium from TDI and strain imaging could be used to investigate subclinical LV systolic and diastolic dysfunction in dogs with the iatrogenic hypercortisolism.

The Prognostic Utility of Echo-Estimated Left Ventricular End-Diastolic Pressure-Volume Relationship in Stable Coronary Artery Disease: The Heart and Soul Study

BACKGROUND

While changes in the left ventricular end-diastolic pressure-volume relationship (LV-EDPVR) can be estimated using echocardiography, their prognostic utility in stable coronary artery disease (CAD) is unknown.

METHODS

Using echo-estimated LV end-diastolic volume index and diastolic function category, the relative position of the LV-EDPVR was defined in 901 participants with stable CAD as: (1) left-shifted, (2) right-shifted, or (3) intermediate. We then evaluated the association of LV-EDPVR position relative to the intermediate category with time to hospitalization for heart failure (HF) or cardiovascular (CV) death using Cox proportional hazards models.

RESULTS

During 7.0 ± 3.1 years of follow-up, there were 207 admissions for HF or CV deaths. Both leftward and rightward shifts of LV-EDPVR were associated with a significantly higher risk of HF or CV death (HR 1.73, 95% CI 1.15-2.62 and HR 6.75, 95% CI 4.02-11.31, respectively). In multivariable-adjusted models, these associations were attenuated but remained significant (HR 1.66, 95% CI 1.08-2.55 for left-shifted and HR 4.19, 95% CI 2.32-7.55 for right-shifted). The association of LV-EDPVR with HF or CV death was no longer significant after inclusion of N-terminal pro-brain natriuretic peptide level as a covariate.

CONCLUSIONS

In stable CAD, echo-estimated leftward and rightward shifts in the LV-EDPVR are associated with HF and CV death. The loss of these associations after adjustment for N-terminal pro-brain natriuretic peptide level suggests that echo-estimated LV-EDPVR captures changes in LV filling pressure at any given LV end-diastolic volume.

Can we diagnose isolated, exercise-induced heart failure with normal ejection fraction?

BACKGROUND

A significant proportion of patients with exertional dyspnea require exercise to diagnose heart failure with normal ejection fraction (HFNEF).

METHODS AND RESULTS

In this review article, we evaluate current data on the prevalence, clinical significance and specifically the establishment of a diagnosis of isolated, exercise-induced HFNEF. Despite the unquestioned clinical importance and high prevalence of exercise-induced HFNEF, there are limited and conflicting data on making a diagnosis of exercise-induced HFNEF. This mostly relies on the evidence of exercise-induced elevation in left ventricular filling pressure (LVFP). At present, there is no agreement on the ability of exercise echocardiographic parameteres to predict exercise-induced LVFP elevation. In addition, even invasively measured exercise LVFP faces the problem of defining normal exercise LVFP values. More data and probably new diagnostic approaches are necessary to reliably diagnose exercise HFNEF.

CONCLUSIONS

There are conflicting results and significant problems associated with the diagnosis of exercise HFNEF. This review hopefully will encourage further research in this difficult but clinically important area of heart failure.

Acute Haemodialysis-induced Changes in Tissue Doppler Echocardiography Parameters

BACKGROUND

Tissue Doppler imaging (TDI) is a method that determines the tissue motion and velocity within the myocardium.

AIMS

To characterize acute haemodialysis (HD)-induced changes in TDI-derived indices for patients that have end-stage renal disease (ESRD).

STUDY DESIGN

Cross sectional study.

METHODS

Conventional echocardiography and TDI methods were applied to study ESRD patients (n=58) before and after HD. Pulmonary venous flow, mitral inflow, and TDI signals of the lateral and septal mitral annulus were examined for the determination of altered left-ventricular diastolic filling parameters. Flow velocities from early- (E) and late-atrial (A) peak transmitral; peak pulmonary vein systolic (S) and diastolic (D); and myocardial peak systolic (Sm) and peak early (Em) and late (Am) diastolic mitral annular velocities were also assessed for changes.

RESULTS

Transmitral E and A velocities and the E/A ratio decreased significantly after HD (p<0.001). Pulmonary vein S (p<0.001) and D (p<0.001) velocities decreased, and S/D ratios increased significantly (p=0.027). HD led to a reduction in septal Em (p<0.001), lateral Em (p=0.006), and Am (p<0.001) velocities. Contrary to the decreases in Em and Am, the Em/Am ratio remained unchanged.

CONCLUSION

A single HD session was associated with an acute deterioration in the diastolic parameters. Since the Em/Am ratio remained unchanged, we conclude that this index is a relatively load-independent measure of diastolic function in HD patients.

Non invasive evaluation of cardiac hemodynamics in end stage renal disease (ESRD)

OBJECTIVE

Volume overload is typical of haemodialysis patients; correct volume status evaluation is crucial in achieving blood pressure homeostasis, hypertension management and good treatment planning. This study evaluates the effect of acute volume depletion on ultrasonographic parameters and suggests two of them as able to predict patients volume overload.

PATIENTS AND INTERVENTION

27 patients with end stage renal disease treated with haemodialysis underwent a complete echocardiographic exam before, after 90 min and at the end of the dialysis.

MAIN OUTCOME AND RESULTS

Blood pressure levels significantly drop during the first 90 min of dialysis (139 ± 20 vs 126 ± 18; p < 0.0001), reaching a steady state with significantly lower values compared to baseline (130 ± 28; p = 0.02). LV and left atrial volume significantly decreased (baseline vs end dialysis 98 ± 32 vs 82 ± 31 p = 0.003 and 28 ± 10 vs. 21 ± 9 cc/m(2) p < 0.001). A significant reduction of systolic function (EF 61.6 % ± 9 vs 58.7 % ± 9 p = 0.04), of diastolic flow velocities (E/A 1.13 ± 0.37 vs. 0.87 ± 0.38 p < 0.001) and mitral annulus TDI tissue velocity (i.e. E' lat 10.6 ± 3 vs. 9.4 ± 3 cm/s; p 0.0001) were observed. Stroke work (SW) and LV end-diastolic diameter (LVEDd) indexed to height 2.7(LVEDdi) were able to predict volume overload: cut off values of respectively 13.5 mm/m(2.7) for LVEDdi and 173 cJ for SW were able to predict with a specificity of 100 % the presence of a volemic overload of at least 4 %.

CONCLUSIONS

Blood pressure, cardiac morphology and function are significantly modified by acute volume depletion and such variations are strictly interrelated. SW and LVEDd/height(2.7) may identify ESRD patients carrying an higher volume load.

Ventricular performance after surgery for a congenital heart defect as assessed using advanced echocardiography: from doppler flow to 3D echocardiography and speckle-tracking strain imaging

A varying degree of impairment of ventricular performance is observed over the long-term after surgery for a congenital heart defect (CHD). Impaired ventricular performance has been shown to be of prognostic value for increased risk of cardiovascular events in adult CHD patients. This emphasizes the importance of delineating the timing and cause of this postoperative impairment. Impairment of ventricular performance could develop over time as a consequence of residua, sequelae and complications of the CHD or surgical procedure. Yet, impaired ventricular performance has also been observed immediately after surgery and can persist and/or worsen over time. This postoperative impairment of ventricular performance is the focus of this review. This article provides an overview of echocardiographic techniques currently used to assess ventricular performance. Furthermore, we review current literature describing ventricular performance, as assessed using echocardiography, after correction of a CHD. In general, a decrease in ventricular performance is observed directly after surgery for CHD’s. Subsequent follow-up of ventricular performance is characterized by a varying degree of postoperative recovery. A consistent observation is the persistent impairment of right-ventricular performance after repair in several different subgroups of CHD patients ranging from ventricular septal defect repair to surgery for Tetralogy of Fallot.

Effects of frequent hemodialysis on ventricular volumes and left ventricular remodeling

BACKGROUND AND OBJECTIVES

Higher left ventricular volume is associated with death in patients with ESRD. This work investigated the effects of frequent hemodialysis on ventricular volumes and left ventricular remodeling.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Frequent Hemodialysis Network daily trial randomized 245 patients to 12 months of six times per week versus three times per week in-center hemodialysis; the Frequent Hemodialysis Network nocturnal trial randomized 87 patients to 12 months of six times per week nocturnal hemodialysis versus three times per week predominantly home-based hemodialysis. Left and right ventricular end systolic and diastolic volumes, left ventricular mass, and ejection fraction at baseline and end of the study were ascertained by cardiac magnetic resonance imaging. The ratio of left ventricular mass/left ventricular end diastolic volume was used as a surrogate marker of left ventricular remodeling. In each trial, the effect of frequent dialysis on left or right ventricular end diastolic volume was tested between predefined subgroups.

RESULTS

In the daily trial, frequent hemodialysis resulted in significant reductions in left ventricular end diastolic volume (-11.0% [95% confidence interval, -16.1% to -5.5%]), left ventricular end systolic volume (-14.8% [-22.7% to -6.2%]), right ventricular end diastolic volume (-11.6% [-19.0% to -3.6%]), and a trend for right ventricular end systolic volume (-11.3% [-21.4% to 0.1%]) compared with conventional therapy. The magnitude of reduction in left and right ventricular end diastolic volumes with frequent hemodialysis was accentuated among patients with residual urine output<100 ml/d (P value [interaction]=0.02). In the nocturnal trial, there were no significant changes in left or right ventricular volumes. The frequent dialysis interventions had no substantial effect on the ratio of left ventricular mass/left ventricular end diastolic volume in either trial.

CONCLUSIONS

Frequent in-center hemodialysis reduces left and right ventricular end systolic and diastolic ventricular volumes as well as left ventricular mass, but it does not affect left ventricular remodeling.

Diastolic dysfunction of the left ventricle is associated with pulmonary edema after renal transplantation

BACKGROUND

Post-operative pulmonary complications are associated with high mortality and graft loss in renal transplantation recipients. Left ventricular diastolic dysfunction is not uncommon in patients with chronic renal failure, including those with preserved left ventricular systolic function. The purpose of this study was to determine the relationship between left ventricular diastolic dysfunction and incidence of post-operative pulmonary edema in renal transplantation recipients with preserved left ventricular systolic function.

METHODS

Pre-operative left ventricular function and incidence of pulmonary edema were retrospectively studied in 209 patients who underwent living-donor renal transplantation between January 2010 and October 2012. Left ventricular systolic and diastolic functions were evaluated by ejection fraction and E/E' ratio, retrospectively, using transthoracic echocardiography. Pulmonary edema was defined by evidence of pulmonary congestion on the chest X-ray together with PaO2 /FiO2 ratio < 300 mmHg.

RESULTS

Eleven out of 190 (5.8%) renal transplantation patients with preserved left ventricular systolic function developed post-operative pulmonary edema. Patients with pulmonary edema had a significantly higher geometric mean (95% confidence interval) of E/E' ratio than those without pulmonary edema [17.8 (14.1-22.5) vs. 11.1 (10.6-11.7), P = 0.001].

CONCLUSION

Pre-operative left ventricular diastolic dysfunction correlated with the development of post-operative pulmonary edema in renal transplantation recipients. Meticulous intraoperative volume therapy is important to avoid post-operative pulmonary edema in such patients.

What Is the Meaning of Increased Myocardial Injury Enzymes during Hemodialysis? A Tissue Doppler Imaging Study

BACKGROUND

Cardiovascular death is decreasing in the general population; however, it appears in still higher rates and even increases gradually in hemodialysis (HD) patients. This situation has led to a debate about cardiovascular adverse effects of HD which lead to significant changes in cardiac and hemodynamic events. It is known that troponins are often elevated in HD patients, and high levels of troponin are associated with increased mortality. Therefore, it is difficult to interpret the value of elevations in chronic kidney disease patients.

METHODS

Echocardiographic and biochemical parameters of 41 patients treated with HD were evaluated before and after a HD session.

RESULTS

HD led to an increased heart rate, and tissue Doppler imaging parameters such as early diastolic mitral peak velocity (E)/early diastolic myocardial peak velocity (é) and septal é decreased significantly after HD. HD caused an increase in troponin I, myoglobin and cardiac creatine kinase (CK MB) levels (p = 0.019, p < 0.001 and p = 0.018, respectively). A decrease in the left ventricular peak systolic myocardial (LV S') velocity (p = 0.011) was detected in patients with increased levels of cardiac damage markers (group 2) compared to those without increased levels of cardiac damage markers (group 1) in HD.

CONCLUSION

A decrease in LV S' velocity was found to be an independent predictor of an increase of myocardial injury enzymes in HD (odds ratio = 1.099; p = 0.039). We concluded that HD may lead to significant acute stress upon the myocardium.

Impact of propofol anesthesia induction on cardiac function in low-risk patients as measured by intraoperative Doppler tissue imaging

BACKGROUND

Despite a few experimental studies showing a dose-dependent myocardial depressive effect of propofol anesthesia induction, few clinical data are available to determine its precise impact on myocardial function, probably because of its brevity and a lack of appropriate evaluation tools. The purpose of this study was to examine the impact of propofol-based anesthesia induction on left ventricular (LV) function using Doppler tissue and speckle-tracking imaging.

METHODS

In 19 low-risk patients with normal LV systolic and diastolic function undergoing noncardiac surgery (all women; mean age, 42 years), propofol bolus (2.0 mg/kg) was administered intravenously for anesthesia induction. LV ejection fraction, global peak systolic longitudinal strain, and tissue Doppler-derived indices of mitral annular velocity during systole (S'), early diastole (e'), and atrial contraction (a') were determined by intraoperative transthoracic echocardiography before and 1, 3, and 5 min after propofol bolus (T0, T1, T2, and T3, respectively).

RESULTS

The following at T1, T2, and T3 were significantly less in magnitude than at T0: septal S' (5.61, 5.61, and 5.51 vs 7.60 cm/sec, P < .001), lateral S' (5.75, 5.89, and 5.94 vs 8.12 cm/sec, P < .001), septal e' (10.10, 10.26, and 10.07 vs 11.4 cm/sec, P < .01), septal a' (6.70, 6.21, and 6.13 vs 8.58 cm/sec, P < .01), lateral a' (7.29, 6.81, and 6.85 vs 9.01 cm/sec, P < .01), and longitudinal strain (-19.36%, -19.71%, and -19.61% vs -22.28%, P < .001). LV ejection fraction was not significantly changed (P = .361).

CONCLUSIONS

Propofol anesthesia induction diminished LV and atrial contraction in low-risk patients with prior normal LV function. Further studies are needed to understand the clinical implications, particularly for higher risk populations.

Effects of subacute dietary salt intake and acute volume expansion on diastolic function in young normotensive individuals

AIMS

Chronic excess salt intake may have blood pressure-independent adverse effects on the heart such as myocardial hypertrophy and fibrosis. Effects of subacute sodium loading with excess dietary salt on diastolic function in normotensive individuals have been conflicting and the mechanisms are poorly understood.

METHODS AND RESULTS

Thirteen healthy normotensive subjects (age 24 ± 4 years) entered a 2-week crossover study with 1 week of a low-salt diet <10 mEq/day and 1 week of a high-salt diet >200 mEq/day. At the end of each study week, left ventricular dimensions, systolic, and diastolic function were assessed with echocardiography before and after 2 L of normal saline infusion. One week of high-salt and low-salt diets did not lead to differences in echocardiographic parameters of systolic or diastolic function, even after rapid volume expansion with saline infusion. The peak early diastolic strain rate (SR) increased after volume loading both after completion of low-salt (1.62 ± 0.23/s vs. 1.82 ± 0.14/s, P < 0.05) and high-salt diets (1.67 ± 0.16/s vs. 1.86 ± 0.22/s, P < 0.05). There was a positive correlation between the peak early diastolic SR and the cardiac index (r = 0.52, P = 0.017).

CONCLUSION

In healthy normotensive individuals, subacute excess dietary sodium intake does not affect diastolic function. The peak early diastolic SR, similar to other mitral Doppler and tissue Doppler parameters of diastolic function, appears to be strongly dependent on pre-load.

Tissue Doppler imaging detects impaired biventricular performance shortly after congenital heart defect surgery

Cardiac surgery with cardiopulmonary bypass is associated with the development of a systemic inflammatory response, which can lead to myocardial damage. However, knowledge concerning the time course of ventricular performance deterioration and restoration after correction of a congenital heart defect (CHD) in pediatric patients is sparse. Therefore, the authors perioperatively quantified left ventricular (LV) and right ventricular (RV) performance using echocardiography. Their study included 141 patients (ages 0-18 years) undergoing CHD correction and 40 control subjects. The study assessed LV systolic performance (fractional shortening) and diastolic performance (mitral Doppler flow) in combination with RV systolic performance [tricuspid annular plane systolic excursion (TAPSE)] and diastolic performance (tricuspid Doppler flow). Additionally, systolic (S') and diastolic (E', A', E/E') tissue Doppler imaging (TDI) measurements were obtained at the LV lateral wall, the interventricular septum, and the RV free wall. Echocardiographic studies were performed preoperatively, 1 day postoperatively, and at hospital discharge after 9 ± 5 days. Although all LV echocardiographic measurements showed a deterioration 1 day after surgery, only LV TDI measurements were impaired in patients at discharge versus control subjects (S': 5.7 ± 2.0 vs 7.1 ± 2.7 cm/s; E': 9.8 ± 3.9 vs 13.7 ± 5.1 cm/s; E/E': 12.2 ± 6.4 vs 8.8 ± 4.3; p < 0.05). In the RV, TAPSE and RV TDI velocities also were impaired in patients at discharge versus control subjects (TAPSE: 9 ± 3 vs 17 ± 5 mm; S': 5.2 ± 1.7 vs 11.4 ± 3.4 cm/s; E': 7.3 ± 2.5 vs 16.3 ± 5.2 cm/s; E/E': 12.5 ± 6.8 vs 4.8 ± 1.9; p < 0.05). Furthermore, longer aortic cross-clamp times were associated with more impaired postoperative LV and RV performance (p < 0.05). In conclusion, both systolic and diastolic biventricular performances were impaired shortly after CHD correction. This impairment was detected only by TDI parameters and TAPSE. Furthermore, a longer-lasting negative influence of cardiopulmonary bypass on myocardial performance was suggested.

Cardiac mechanics are impaired during fatiguing exercise and cold pressor test in healthy older adults

We sought to determine how the aging left ventricle (LV) responds to sympathetic nervous system (SNS) activation. Three separate echocardiographic experiments were conducted in 11 healthy young (26 ± 1 yr) and 11 healthy older (64 ± 1 yr) adults. Tissue Doppler imaging was used to measure systolic myocardial velocity (S(m)), early diastolic myocardial velocity (E(m)), and late diastolic myocardial velocity (A(m)) during isometric fatiguing handgrip (IFHG), a 2-min cold pressor test (CPT), and 5 min of normobaric hypoxia. Heart rate (HR) and mean arterial pressure (MAP) were also monitored on a beat-by-beat basis; rate pressure product (RPP) was used as an index of myocardial oxygen demand. At peak IFHG, the groups had similar increases in RPP, but the ΔS(m) was significantly greater (i.e., larger impairment) in the older subjects (-0.82 ± 0.13 cm/s) compared with the young subjects (0.37 ± 0.30 cm/s). At peak IFHG, the ΔE(m) was similar between older (-1.59 ± 0.68 cm/s) and young subjects (-1.06 ± 0.76 cm/s). In response to the CPT, both S(m) and E(m) were reduced in the older adults but did not change relative to baseline in the young subjects. Normobaric hypoxia elevated HR and RPP in both groups but did not alter Tissue Doppler parameters. These data indicate that S(m) and E(m) are reduced in healthy older adults during IFHG and CPT. We speculate that suboptimal LV adaptations to SNS stress may partly explain why acute heavy exertion can trigger myocardial ischemia.

Preload dependence of gated cardiac SPECT-derived ventricular volumes in hemodialysis patients

BACKGROUND

In hemodialysis (HD) patients, the intravascular volume expansion of the pre-HD state leads to a high preload. We aim to examine its effect on myocardial perfusion gated SPECT (MPGS)-derived left ventricular (LV) volumes.

METHODS

The study comprised 50 end-stage renal disease (ESRD) patients on HD with normal 2-day stress/rest MPGS performed for kidney transplantation risk assessment. Patients (pts) comprised 23 men/27 women, with mean age of 59.4 ± 7.1 years. The time elapsed from the last HD session in hours was calculated on both days, and patients were classified according to whether it was higher (group A: 19 pts), lower (group B: 27 pts), or equal (group C: 4 pts) on the stress vs the rest day. End-diastolic, end-systolic volumes (EDV, ESV), and left ventricular ejection fraction (LVEF) were determined using QGS™ software. Transient ischemic dilation (TID) ratios were derived from the nongated images using QPS™ software.

RESULTS

Volumes were significantly higher at stress in group A, at rest in group B, and similar in group C. TID ratios were significantly higher in group A vs groups B and C.

CONCLUSIONS

MPGS-derived ventricular volumes are preload dependent. The high preload of the pre-HD state may mimic ischemic TID if occurring on the stress day and create confusion if coinciding with the rest day.

Assessment of left ventricular hemodynamics and function of patients with uremia by vortex formation using vector flow mapping

A novel echocardiographic method, vector flow mapping (VFM), acquires velocity vector from color Doppler velocity data. The purpose of this study was to evaluate whether VFM could provide useful information on intracardiac flow and helpful to evaluate left ventricular (LV) function. Thirty-eight patients with uremia undergoing hemodialysis and 30 healthy volunteers were enrolled. The maximum vector velocity, maximum diameter and duration of the intracardiac vortex were measured using VFM software during systole and diastole. The maximum vector velocity of the vortex and the peak velocities at the basal septum and lateral mitral annulus measured by tissue Doppler imaging (TDI) were correlated. The maximum diameter and duration of vortex formation were significantly higher in uremic patients compared with the control group during the ejection phase (40.6 ± 7.9 cm/sec vs. 28.1 ± 3.9 cm/sec; 297.1 ± 22.1 msec vs. 145.4 ± 19.3 msec, all P < 0.001). The maximal diameters of the vortex were higher in uremic patients compared with the control group during diastole (25.6 ± 3.4 mm vs. 16.4 ± 2.1 mm; 34.3 ± 3.1 mm vs. 26.8 ± 3.9 mm; 37.5 ± 2.4 mm vs. 20.9 ± 2.1 mm; all P < 0.001). The maximum vector velocities were lower in mid-diastole and late diastole (23.6 ± 2.3 cm/sec vs. 45.2 ± 3.7 cm/sec; 31.9 ± 2.9 cm/sec vs. 54.7 ± 3.2 cm/sec, all P < 0.001). There was a correlation between the maximum vector velocity of the vortex in mid-diastole and E'/A' at the septum and lateral mitral annulus (r = 0.70, r = 0.76, P < 0.001). Vortex can be utilized to provide intracardiac dynamic information using VFM and it may be a good supplement for evaluating LV function.

Left ventricular strain and peak systolic velocity: responses to controlled changes in load and contractility, explored in a porcine model

BACKGROUND

Tissue velocity echocardiography is increasingly used to evaluate global and regional cardiac function. Previous studies have suggested that the quantitative measurements obtained during ejection are reliable indices of contractility, though their load-sensitivity has been studied in different settings, but still remains a matter of controversy. We sought to characterize the effects of acute load change (both preload and afterload) and change in inotropic state on peak systolic velocity and strain as a measure of LV contractility.

METHODS

Thirteen anesthetized juvenile pigs were studied, using direct measurement of left ventricular pressure and volume and transthoracic echocardiography. Transient inflation of a vena cava balloon catheter produced controlled load alterations. At least eight consecutive beats in the sequence were analyzed with tissue velocity echocardiography during the load alteration and analyzed for change in peak systolic velocities and strain during same contractile status with a controlled load alteration. Two pharmacological inotropic interventions were also included to generate several myocardial contractile conditions in each animal.

RESULTS

Peak systolic velocities reflected the drug-induced changes in contractility in both radial and longitudinal axis. During the acute load change, the peak systolic velocities remain stable when derived from signal in the longitudinal axis and from the radial axis. The peak systolic velocity parameter demonstrated no strong relation to either load or inotropic intervention, that is, it remained unchanged when load was systematically and progressively varied (peak systolic velocity, longitudinal axis, control group beat 1-5.72 ± 1.36 with beat 8-6.49 ± 1.28 cm/sec, 95% confidence interval), with the single exception of the negative inotropic intervention group where peak systolic velocity decreased a small amount during load reduction (beat 1-3.98 ± 0.92 with beat 8-2.72 ± 0.89 cm/sec). Systolic strain, however, showed a clear degree of load-dependence.

CONCLUSIONS

Peak systolic velocity appears to be load-independent as tested by beat-to-beat load reduction, while peak systolic strain appears to be load-dependent in this model. Peak systolic velocity, in a controlled experimental model where successive beats during load alteration are assessed, has a strong relation to contractility. Peak systolic velocity, but not peak strain rate, is largely independent of load, in this model. More study is needed to confirm this finding in the clinical setting.

Effect of preload on left atrial function: evaluated by tissue Doppler and strain imaging

AIMS

Both strain and strain rate (SR) measure the regional myocardial deformation and can assess phasic left atrial (LA) function. However, there is still a lack of evidence for their volume independency. In this study, strain and SR determined by tissue Doppler imaging were used to evaluate the effect of preload reduction in end-stage renal disease patients who were undergoing regular haemodialysis (HD).

METHODS AND RESULTS

Forty-one subjects who underwent transthoracic echocardiography just before and after HD were enrolled. LA strain was measured during late systole, and LA peak tissue velocity and SR were measured during systole and during early and late diastolic periods. The values of tissue velocity, strain, and SR were obtained in the basal septal, lateral, inferior, and anterior walls of the LA. The mean strain value was 23.89 ± 7.29% at baseline and decreased to 21.88 ± 5.85% after HD (P = 0.019). SR during systole (before HD 1.55 ± 0.40; after HD 1.38 ± 0.35, P = 0.001) and early diastole (before HD -1.41 ± 0.54; after HD -1.16 ± 0.45, P = 0.001) also changed. However, the acute preload change caused by HD did not affect the peak tissue velocity (before HD -6.34 ± 1.58 cm/s; after HD -6.46 ± 1.54 cm/s, P = 0.436) and the SR (before HD -1.36 ± 0.45/s; after HD -1.34 ± 0.29/s, P = 0.621) measured during late diastole.

CONCLUSION

Both tissue velocity and SR during late diastole, representing the contractile function of the LA, are relatively preload-independent parameters and are available for the evaluation of the LA function.