Evaluation of the myocardial performance index and tissue doppler imaging by comparison to near-simultaneous catheter measurements in pediatric cardiac transplant patients

Imaging of Cardiac Transplantation: An Overview

Heart transplantation (HTx) remains the optimal treatment for selected patients with end-stage advanced heart failure. However, survival is limited early by acute rejection and long term by cardiac allograft vasculopathy (CAV). Even though the diagnosis of rejection is based on histology, cardiac imaging provides a pivotal role for early detection and severity assessment of these hazards. The present review focuses on the use and reliability of different invasive and non-invasive imaging modalities to detect and monitor CAV and rejection after HTx. Coronary angiography remains the corner stone in routine CAV surveillance. However, angiograms are invasive and underestimates the CAV severity especially in the early phase. Intravascular ultrasound and optical coherence tomography are invasive methods for intracoronary imaging that detects early CAV lesions not evident by angiograms. Non-invasive imaging can be divided into myocardial perfusion imaging, anatomical/structural imaging and myocardial functional imaging. The different non-invasive imaging modalities all provide clinical and prognostic information and may have a gatekeeper role for invasive monitoring. Acute rejection and CAV are still significant clinical problems after HTx. No imaging modality provides complete information on graft function, coronary anatomy and myocardial perfusion. However, a combination of invasive and non-invasive modalities at different stages following HTx should be considered for optimal personalized surveillance and risk stratification.

Echocardiographic RV-E/e' for predicting right atrial pressure: a review

Right atrial pressure (RAP) is a key cardiac parameter of diagnostic and prognostic significance, yet current two-dimensional echocardiographic methods are inadequate for the accurate estimation of this haemodynamic marker. Right-heart trans-tricuspid Doppler and tissue Doppler echocardiographic techniques can be combined to calculate the right ventricular (RV) E/e′ ratio – a reflection of RV filling pressure which is a surrogate of RAP. A systematic search was undertaken which found seventeen articles that compared invasively measured RAP with RV-E/e′ estimated RAP. Results commonly concerned pulmonary hypertension or advanced heart failure/transplantation populations. Reported receiver operating characteristic analyses showed reasonable diagnostic ability of RV-E/e′ for estimating RAP in patients with coronary artery disease and RV systolic dysfunction. The diagnostic ability of RV-E/e′ was generally poor in studies of paediatrics, heart failure and mitral stenosis, whilst results were equivocal in other diseases. Bland–Altman analyses showed good accuracy but poor precision of RV-E/e′ for estimating RAP, but were limited by only being reported in seven out of seventeen articles. This suggests that RV-E/e′ may be useful at a population level but not at an individual level for clinical decision making. Very little evidence was found about how atrial fibrillation may affect the estimation of RAP from RV-E/e′, nor about the independent prognostic ability of RV-E/e′ . Recommended areas for future research concerning RV-E/e′ include; non-sinus rhythm, valvular heart disease, short and long term prognostic ability, and validation over a wide range of RAP.

Echocardiographic RV-E/e′ for predicting right atrial pressure: a review

Right atrial pressure (RAP) is a key cardiac parameter of diagnostic and prognostic significance, yet current two-dimensional echocardiographic methods are inadequate for the accurate estimation of this haemodynamic marker. Right-heart trans-tricuspid Doppler and tissue Doppler echocardiographic techniques can be combined to calculate the right ventricular (RV) E/e′ ratio–a reflection of RV filling pressure which is a surrogate of RAP. A systematic search was undertaken which found seventeen articles that compared invasively measured RAP with RV-E/e′ estimated RAP. Results commonly concerned pulmonary hypertension or advanced heart failure/transplantation populations. Reported receiver operating characteristic analyses showed reasonable diagnostic ability of RV-E/e′ for estimating RAP in patients with coronary artery disease and RV systolic dysfunction. The diagnostic ability of RV-E/e′ was generally poor in studies of paediatrics, heart failure and mitral stenosis, whilst results were equivocal in other diseases. Bland–Altman analyses showed good accuracy but poor precision of RV-E/e′ for estimating RAP, but were limited by only being reported in seven out of seventeen articles. This suggests that RV-E/e′ may be useful at a population level but not at an individual level for clinical decision making. Very little evidence was found about how atrial fibrillation may affect the estimation of RAP from RV-E/e′, nor about the independent prognostic ability of RV-E/e′. Recommended areas for future research concerning RV-E/e′ include; non-sinus rhythm, valvular heart disease, short and long term prognostic ability, and validation over a wide range of RAP.

Assessment of biatrial function in clinically well pediatric bicaval heart transplantation patients by three-dimensional echocardiography

Atrial size and function are closely correlated with atrial contributions to cardiovascular performance. Therefore, in this study, we aimed to assess atrial size and function in pediatric heart transplantation (HTx) patients using three-dimensional echocardiography (3DE). We enrolled 33 clinically well pediatric HTx patients and 33 healthy controls with a similar distribution of sex and age to the HTx patients. All patients underwent two-dimensional echocardiography (2DE) and 3DE. 2DE- and 3DE-derived biatrial maximal volume (Vmax), minimal volume (Vmin), ejection volume (EV), ejection fraction (EF), volume before atrial contraciton (VpreA), passive EV, passive EF, active EV and active EF were obtained in all patients. The 3D left atrail (LA) Vmax, Vmin and VpreA increased significantly in HTx patients after being indexed by BSA, while 3D LAEV and passive EV decreased significantly (P < 0.05). Moreover, the 3D LAEF, LA passive EF, and LA active EF all decreased significantly in HTx patients (P < 0.05). The 3D right atrial (RA) Vmax, Vmin, and VpreA increased significantly in HTx patients (P < 0.05), while the 3D RAEF and RA passive EF decreased significantly in HTx patients (P < 0.05). 3DE-derived LAVmax, LAVpreA, LA passive EV, LAEF, and LA passive EF were all lower than the corresponding 2D parameters. 3DE-derived RAVpreA, RA passive EV and RAEF were all lower than the corresponding 2D parameters. Atrial sizes and function assessed by 3DE- and 2DE-derived parameters, yield significantly discordant results in pediatric HTx patients. 3DE confirms significantly enlarged atrial sizes and decreased atrial functions in pediatric HTx patients.

Is Doppler echocardiography useful for estimating left ventricular filling pressures in pediatric heart transplant recipients?

LV E/E' ratio obtained using Doppler echocardiography is considered a surrogate for LV filling pressure in adults but has performed poorly in children. We hypothesized that LV E/E' ratio Z-score, adjusted for age, will relate more strongly to LV filling pressures than LV E/E' ratio in pediatric HT recipients. We analyzed 751 echocardiograms performed within 24 hours of a heart catheterization in 122 pediatric HT recipients (median age at HT 13 years, median 6 studies per patient). The primary end-point was PCWP, assessed both as a continuous and a binary variable. Associations with LV E/E' ratios and z-scores were assessed using generalized estimating equations models. PCWP, LV E/E' ratios (using E' from LV free wall, septum, and their average), and LV E/E' ratio Z-scores, all declined over time after HT. LV E/E' ratios and their Z-scores were significantly associated with PCWP assessed as a continuous variable (P < 0.001 for all); however, the relationship was weak (R² range, 0.083 to 0.121). LV E/E' ratios and their Z-scores were also significantly associated with PCWP as a binary variable (P < 0.001 for all) but with only modest ability to discriminate PCWP ≥15 mm Hg (c-statistic range, 0.660 to 0.695). The association between LV E/E' ratio and PCWP in pediatric HT recipients is modest. Using a LV E/E' ratio Z-score did not result in significantly improved association with PCWP. Current Doppler echocardiographic methods are unreliable for estimating LV filling pressures in pediatric HT recipients.

Comparison of echocardiographic measurements to invasive measurements of diastolic function in infants with single ventricle physiology: a report from the Pediatric Heart Network Infant Single Ventricle Trial

BACKGROUND

While echocardiographic parameters are used to quantify ventricular function in infants with single ventricle physiology, there are few data comparing these to invasive measurements. This study correlates echocardiographic measures of diastolic function with ventricular end-diastolic pressure in infants with single ventricle physiology prior to superior cavopulmonary anastomosis.

METHODS

Data from 173 patients enrolled in the Pediatric Heart Network Infant Single Ventricle enalapril trial were analysed. Those with mixed ventricular types (n = 17) and one outlier (end-diastolic pressure = 32 mmHg) were excluded from the analysis, leaving a total sample size of 155 patients. Echocardiographic measurements were correlated to end-diastolic pressure using Spearman's test.

RESULTS

Median age at echocardiogram was 4.6 (range 2.5-7.4) months. Median ventricular end-diastolic pressure was 7 (range 3-19) mmHg. Median time difference between the echocardiogram and catheterisation was 0 days (range -35 to 59 days). Examining the entire cohort of 155 patients, no echocardiographic diastolic function variable correlated with ventricular end-diastolic pressure. When the analysis was limited to the 86 patients who had similar sedation for both studies, the systolic:diastolic duration ratio had a significant but weak negative correlation with end-diastolic pressure (r = -0.3, p = 0.004). The remaining echocardiographic variables did not correlate with ventricular end-diastolic pressure.

CONCLUSION

In this cohort of infants with single ventricle physiology prior to superior cavopulmonary anastomosis, most conventional echocardiographic measures of diastolic function did not correlate with ventricular end-diastolic pressure at cardiac catheterisation. These limitations should be factored into the interpretation of quantitative echo data in this patient population.

The Relationship Between Heart Rate and Left Ventricular Isovolumic Relaxation During Normoxia and Hypoxia-Asphyxia in Newborn Piglets

Background: Many asphyxiated neonates have cardiac complications including arrhythmia and contractile dysfunction. Little is known about the relationship between heart rate (HR) and diastolic function in asphyxiated neonates. We aimed to study the relationship between HR and left ventricular (LV) isovolumic relaxation (IVR) in neonates with asphyxia using a swine model.

Methods: Term newborn piglets were anesthetized and acutely instrumented with the placement of Millar^® catheter in the left ventricle. Hemodynamic parameters including HR, cardiac output, stroke volume, dP/dt_max and dP/dt_min, and IVR time constant (Tau) were continuously measured and recorded. Sixteen piglets were exposed to 50-minute normocapnic hypoxia followed by asphyxia (mean of 3.2 min) by clamping of the endotracheal tube. Sham-operated piglets (n = 11) had no hypoxia nor asphyxia. The relationship between HR and other hemodynamic parameters were analyzed using Pearson Product Moment correlation test.

Results: Asphyxiated piglets had cardiogenic shock and metabolic acidosis (vs. sham-operated piglets). There were significant correlations between HR and diastolic function as shown by Tau at baseline (sham-operated: r = -0.68, p = 0.02; asphyxia: r = -0.55, p = 0.03) and during normoxia (53 min) of sham-operated piglets (r = -0.69, p = 0.02). HR and Tau was not correlated during hypoxia-asphyxia (HA) (r = -0.01, p = 0.97). Cardiac output was tightly correlated with stroke volume (p < 0.001) but not HR throughout the experimental period in both groups. There was no significant correlation between HR and other hemodynamic parameters during the experimental period in both groups.

Conclusion: We observed an uncoupling between HR and IVR Tau of the neonatal heart during HA, which deserves further studies of the relationship between HR and LV diastolic function.

Prognostic value of exercise myocardial deformation and haemodynamics in long-term heart-transplanted patients

Aims

The study evaluated exercise left ventricular global longitudinal strain (LVGLS) and invasive haemodynamics for major adverse cardiac events (MACE) prediction in heart‐transplanted (HTx) patients.

Methods and results

The study comprised 74 stable consecutive HTx patients who were followed at the Department of Cardiology, Aarhus University Hospital, Denmark, from August 2013 to January 2017. All patients were transplanted a minimum of 12 months before study entry and were included at the time of their routine annual coronary angiography. A symptom‐limited haemodynamic exercise test with simultaneous echocardiographic study was performed. The primary endpoint was MACE during follow‐up defined as heart failure hospitalization, treated rejection episodes, coronary event, or cardiac death.

The median time since transplant was 5 years [1:12] and the median follow‐up was 1095 days [391;1506]. Thirty patients (41%) experienced MACE during follow‐up. Patients who suffered MACE had an impaired resting and peak exercise systolic function in form of a lower LV ejection fraction (Rest: 56 ± 12% vs. 65 ± 7%, P < 0.001; Peak 64 ± 13% vs. 72 ± 6%, P < 0.01) and LVGLS (Rest: 13 ± 4% vs. 16 ± 2%, P < 0.01; Peak: 15 ± 6% vs. 20 ± 4%, P = 0.0001) than patients without MACE episodes. In contrast, resting diastolic filling patterns were comparable between patients suffering from MACE and patients without MACE.

At rest, pulmonary capillary wedge pressure (mPCWP) and cardiac index did not predict MACE, whereas increased right atrial pressure (mRAP) was associated with increased MACE risk. Patients with peak exercise mPCWP >23 mmHg [hazard ratio (HR) 2.5, 95% confidence interval (CI): 1.2–5.4], cardiac index <5.9 L/min/m² (HR 2.7, 95% CI: 1.0–6.3), or mRAP >13 mmHg (HR 2.7, 95% CI: 1.1–6.3) had increased MACE risk.

Patients with exercise‐induced LVGLS increase <3.5% and peak exercise cardiac index <5.9 L/min/m² [HR 6.1 (95% CI: 2.2–17.1)] or mPCWP >23 mmHg [HR 6.1 (95% CI: 2.1–17.5)] or mRAP >13 mmHg [HR 7.5 (95% CI: 2.3–23.9)] had the highest MACE risk.

Conclusions

Resting haemodynamic parameters were poor MACE predictors in long‐term HTx patients. In contrast, peak exercise mPCWP, mRAP, and CI were significant MACE predictors. LVGLS both at rest and during exercise were significant MACE predictors, and the combined model with peak exercise LVGLS and peak exercise mPCWP, mRAP, and CI clearly identified high‐risk HTx patients in relation cardiovascular endpoints independently of time since HTx.

Longer Ischemic Time is Associated with Increased Ventricular Stiffness as Measured by Pressure-Volume Loop Analysis in Pediatric Heart Transplant Recipients

BACKGROUND

The purpose of this study was to investigate the associations between clinical factors and cardiac function as measured by pressure-volume loops (PVLs) in a pediatric heart transplant cohort.

METHODS

Patients (age < 20 years) who underwent heart transplantation presenting for a clinically indicated catheterization were enrolled. PVLs were recorded using microconductance catheters (CD Leycom^®, Zoetermeer, Netherlands). Demographic data, serum B-type natriuretic peptide (BNP), time from transplant, ischemic time, presence of transplant coronary artery disease, donor-specific antibodies, and history of rejection were recorded at the time of catheterization. PVL data included contractility indices: end-systolic elastance and preload recruitable stroke work; ventricular-arterial coupling index; ventricular stiffness constant, Beta; and isovolumic relaxation time constant, tau. Associations between PVL measures and clinical data were investigated using non-parametric statistical tests.

RESULTS

A total of 18 patients were enrolled. Median age was 8.7 years (IQR 5-14 years). There were ten males and eight females. Six patients had a history of rejection and ten had positive donor-specific antibodies. There was no transplant coronary artery disease. Median BNP was 100 pg/mL (IQR 46-140). Time from transplant to PVL obtained during catheterization procedure was 4.1 years (IQR 1.7-7.8 year). No single clinical characteristic was statistically significant when correlated with PVL data. However, longer ischemic time was associated with worse Beta (r = 0.49, p = 0.05).

CONCLUSIONS

Our study found that longer ischemic times are associated with increased left ventricular stiffness. No other single clinical variable is associated with cardiac dysfunction as determined by PVL analysis.

Normal Reference Ranges for Transthoracic Echocardiography Following Heart Transplantation

BACKGROUND

Heart function following heart transplantation (HTx) is influenced by numerous factors. It is typically evaluated using transthoracic echocardiography, but reference values are currently unavailable for this context. The primary aim of the present study was to derive echocardiographic reference values for chamber size and function, including cardiac mechanics, in clinically stable HTx patients.

METHODS

The study enrolled 124 healthy HTx patients examined prospectively. Patients underwent comprehensive two-dimensional echocardiographic examinations according to contemporary guidelines. Results were compared with recognized reference values for healthy subjects.

RESULTS

Compared with guidelines, larger atrial dimensions were seen in HTx patients. Left ventricular (LV) diastolic volume was smaller, and LV wall thickness was increased. With respect to LV function, both ejection fraction (62 ± 7%, P < .01) and global longitudinal strain (-16.5 ± 3.3%, P < .0001) were lower. All measures of right ventricular (RV) size were greater than reference values (P < .0001), and all measures of RV function were reduced (tricuspid annular plane systolic excursion 15 ± 4 mm [P < .0001], RV systolic tissue Doppler velocity 10 ± 6 cm/sec [P < .0001], fractional area change 40 ± 8% [P < .0001], and RV free wall strain -16.9 ± 4.2% [P < .0001]). Ejection fraction and LV global longitudinal strain were significantly lower in patients with previous rejection.

CONCLUSION

The findings of this study indicate that the distribution of routinely used echocardiographic measures differs between stable HTx patients and healthy subjects. In particular, markedly larger RV and atrial volumes and mild reductions in both LV and RV longitudinal strain were evident. The observed differences could be clinically relevant in the assessment of HTx patients, and specific reference values should be applied in this context.

Utility of Echocardiography in the Assessment of Left Ventricular Diastolic Function and Restrictive Physiology in Children and Young Adults with Restrictive Cardiomyopathy: A Comparative Echocardiography-Catheterization Study

The aim of the study is to determine the utility of echocardiography in the assessment of diastolic function in children and young adults with restrictive cardiomyopathy (RCM). RCM is a rare disease with high mortality requiring frequent surveillance. Accurate, noninvasive echocardiographic measures of diastolic function may reduce the need for invasive catheterization. Single-center, prospective, observational study of pediatric and young adult RCM patients undergoing assessment of diastolic parameters by simultaneous transthoracic echocardiogram (TTE) and invasive catheterization. Twenty-one studies in 15 subjects [median (IQR) = 13.8 years (7.0-19.2), 60% female] were acquired with median left ventricular end-diastolic pressure (LVEDP) 21 (IQR 18-25) mmHg. TTE parameters of diastolic function, including pulmonary vein A wave duration (r _s  = 0.79) and indexed left atrial volume (r _s  = 0.49), demonstrated significant positive correlation, while mitral valve A (r _s  = -0.44), lateral e' (r _s  = -0.61) and lateral a' (r _s  = -0.61) velocities showed significant negative correlation with LVEDP. Lateral a' velocity (≤0.042 m/s) and pulmonary vein A wave duration (≥156 m/s) both had sensitivity and specificity ≥80% for LVEDP ≥ 20 mmHg. In pediatric and young adult patients with RCM, lateral a' velocity and pulmonary vein A wave duration predicted elevated LVEDP with high sensitivity and specificity; however, due to technical limitations the latter was reliably measured in 12/21 patients. These noninvasive parameters may have utility in identifying patients that require further assessment with invasive testing. These findings require validation in a multicenter prospective cohort prior to widespread clinical implementation.

Speckle-Tracking Echocardiographic Measures of Right Ventricular Diastolic Function Correlate with Reference Standard Measures Before and After Preload Alteration in Children

The accuracy of echocardiographic measures of right ventricular (RV) diastolic function has been sparsely studied. Our objective was to evaluate the correlation between echocardiographic and reference standard measures of RV diastolic function derived from micromanometer pressure analysis before and after preload alteration in children. Echocardiograms and micromanometer pressure analyses were prospectively performed before and after fluid bolus in children undergoing right heart catheterization. The isovolumic relaxation time constant (τ) and end-diastolic pressure (EDP) were measured. Conventional and speckle-tracking echocardiographic (STE) parameters of RV systolic and diastolic function were assessed. Normal saline bolus was given to increase RV EDP by 20 %. Twenty-eight studies were performed in 22 patients with congenital heart disease or postheart transplantation. Mean age was 8.7 ± 6.1 years. RV longitudinal early diastolic strain rate (EDSR) correlated with τ before (r = 0.57, p = 0.001) and after fluid bolus (r = 0.48, p = 0.008). No conventional echocardiographic measures correlated with τ both before and after fluid bolus. Multiple regression analysis revealed RV EDSR and LV circumferential EDSR as independent predictors of RV τ. There were no independent predictors of EDP. RV EDSR appears to correlate with the reference standard measure of early active ventricular relaxation in children at baseline and after changes in preload. Conventional echocardiographic measures of diastolic function were not predictive of diastolic function after preload alteration. Future studies should assess the prognostic significance of STE measures of diastolic function in this population.

Correlations Between Echocardiographic Systolic and Diastolic Function with Cardiac Catheterization in Biventricular Congenital Heart Patients

Newer echocardiographic techniques may allow for more accurate assessment of left ventricular (LV) function. Adult studies have correlated these echocardiographic measurements with invasive data, but minimal data exist in the pediatric congenital heart population. Purpose of this study was to evaluate which echocardiographic measurements correlated best with LV systolic and diastolic catheterization parameters. Patients with two-ventricle physiology who underwent simultaneous echocardiogram and cardiac catheterization were included. Images were obtained in the four-chamber view. LV systolic echocardiographic data included ejection fraction, displacement, tissue Doppler imaging (TDI) s' wave, global longitudinal strain, and strain rate (SR) s' wave. Diastolic echocardiographic data included mitral E and A waves, TDI e' and a' waves, and SRe' and SRa' waves. E/TDI e', TDI e'/TDI a', E/SRe', and SRe'/SRa' ratios were also calculated. Catheterization dP/dt was used as a marker for systolic function, and LV end-diastolic pressure (EDP) was used as a marker for diastolic function. Correlations of the echocardiographic and catheterization values were performed using Pearson correlation. Twenty-nine patients were included (14 females, 15 males). Median age at catheterization was 3.4 years (0.04-17.4 years). dP/dt was 1258 ± 353 mmHg/s, and LVEDP was 10.8 ± 2.4 mmHg. There were no significant correlations between catheterization dP/dt and systolic echocardiographic parameters. LVEDP correlated significantly with SRe' (r = -0.4, p = 0.03), SRa' (r = -0.4, p = 0.03), and E/SRe' (r = 0.5, p = 0.004). In pediatric congenital heart patients, catheterization dP/dt did not correlate with echocardiographic measurements of LV systolic function. Further studies are needed to determine which echocardiographic parameter best describes LV systolic function in this population. Strain rate analysis significantly correlated with LVEDP. Strain rate analysis should be considered as an alternative method to estimate LVEDP in this patient population.

Diagnosis and management of coronary allograft vasculopathy in children and adolescents

Coronary allograft vasculopathy remains one of the leading causes of death beyond the first year post transplant. As a result of denervation following transplantation, patients lack ischaemic symptoms and presentation is often late when the graft is already compromised. Current diagnostic tools are rather invasive, or in case of angiography, significantly lack sensitivity. Therefore a non-invasive tool that could allow early diagnosis would be invaluable.This paper review the disease form its different diagnosis techniques,including new and less invasive diagnostic tools to its pharmacological management and possible treatments.

Evaluation of longitudinal myocardial deformation by 2-dimensional speckle-tracking echocardiography in heart transplant recipients: relation to coronary allograft vasculopathy

BACKGROUND

Coronary allograft vasculopathy (CAV) in heart transplant (HTx) recipients is characterized by diffuse affection of epicardial and intramyocardial coronary vessels. Despite significant CAV and anticipated affected myocardial function, left ventricular ejection fraction (LVEF) is often within the normal range, indicating the need of more sophisticated non-invasive methods to detect impaired myocardial function caused by CAV. Global longitudinal strain (GLS) represents a new echocardiographic measurement of systolic myocardial deformation. The aim of the study was to evaluate the relation between GLS measured by 2-dimensional speckle-tracking echocardiography and CAV in HTx patients.

METHODS

The study included 178 HTx patients and 20 healthy, age-matched individuals. All patients had an extensive echocardiographic evaluation and coronary angiography assessing CAV. CAV was classified according to International Society of Heart and Lung Transplantation classification (CAV0-3).

RESULTS

CAV was seen in 38.8% of patients. Compared with controls (-20.6% ± 1.4%), GLS was significantly reduced according to the degree of CAV (CAV0, -16.7% ± 2.4%; CAV1, -15.2% ± 2.9%; CAV2-3, -14.0% ± 3.8%; controls, -20.6% ±1.4%; pTREND < 0.0001). In addition, we found decreasing peak systolic mitral annular velocities (pTREND = 0.0040), tissue-tracking values (pTREND = 0.0002), and LVEF according to CAV class (CAV0, 65.3% ± 5.4%; CAV2-3, 56.9% ± 11.7%; pTREND < 0.0001). The HTx population showed significant restrictive physiology compared with the control population, but no significant correlation was seen between CAV class and traditional diastolic parameters such as E/A ratio (pTREND = 0.38) or E-deceleration time (pTREND = 0.14).

CONCLUSIONS

In contrast to LVEF and conventional pulsed mitral Doppler flow parameters used in the CAV classification, GLS relates to the presence and degree of CAV. The present results suggest GLS as a new method to be included in the monitoring of graft function in relation to CAV.

Doppler tissue imaging in children following cardiac transplantation: a comparison to catheter derived hemodynamics

  Previous studies have demonstrated a correlation between E:E(a) and ventricular filling pressure in adults after heart transplantation. We sought to determine if E:E(a) correlates with filling pressure after heart transplantation in children. A prospective analysis of children who have undergone heart transplantation was performed. Inflow and myocardial velocities were recorded and compared to catheter-derived filling pressures and rejection status. We performed 61 studies in 49 subjects. No correlation was found between septal E:E(a) and PCWP (r=0.14, p=0.28); or between lateral tricuspid E:E(a) and mean RAp (r=0.04, p=0.79). However, the mean PCWP was higher among subjects with elevated septal E:E(a) (>12) compared to normal E:E(a) (12.3±2.8mmHg vs. 10.1±2.9mmHg, p=0.02). Similarly, mean RAp was higher among subjects with an elevated lateral tricuspid E:E(a) (>10) compared to normal lateral tricuspid E:E(a) (7.7±2.1mmHg vs. 6.0±2.4mmHg, p=0.04). Elevated septal E:E(a) was also associated with high-grade cellular rejection (OR=17.3 [95% CI 1.4-221], p=0.028). In children following heart transplant, E:E(a) does not correlate well with the range of filling pressures seen after pediatric heart transplantation. However, a septal E:E(a)>12 is associated with elevated PCWP and high grade cellular rejection and a lateral tricuspid E:E(a)>10 is associated with elevated mean RAp.