Echocardiographic Automated Border Detection Research Articles

Transesophageal echocardiographic automated border detection to predict fluid responsiveness in mechanically ventilated patients

Transesophageal echocardiographic automated border detection to predict fluid responsiveness in mechanically ventilated patients

Prediction of fluid responsiveness using respiratory variations in left ventricular stroke area by transoesophageal echocardiographic automated border detection in mechanically ventilated patients

BackgroundLeft ventricular stroke area by transoesophageal echocardiographic automated border detection has been shown to be strongly correlated to left ventricular stroke volume. Respiratory variations in left ventricular stroke volume or its surrogates are good predictors of fluid responsiveness in mechanically ventilated patients. We hypothesised that respiratory variations in left ventricular stroke area (ΔSA) can predict fluid responsiveness.MethodsEighteen mechanically ventilated patients undergoing coronary artery bypass grafting were studied immediately after induction of anaesthesia. Stroke area was measured on a beat-to-beat basis using transoesophageal echocardiographic automated border detection. Haemodynamic and echocardiographic data were measured at baseline and after volume expansion induced by a passive leg raising manoeuvre. Responders to passive leg raising manoeuvre were defined as patients presenting a more than 15% increase in cardiac output.ResultsCardiac output increased significantly in response to volume expansion induced by passive leg raising (from 2.16 ± 0.79 litres per minute to 2.78 ± 1.08 litres per minute; p < 0.01). ΔSA decreased significantly in response to volume expansion (from 17% ± 7% to 8% ± 6%; p < 0.01). ΔSA was higher in responders than in non-responders (20% ± 5% versus 10% ± 5%; p < 0.01). A cutoff ΔSA value of 16% allowed fluid responsiveness prediction with a sensitivity of 92% and a specificity of 83%. ΔSA at baseline was related to the percentage increase in cardiac output in response to volume expansion (r = 0.53, p < 0.01).ConclusionΔSA by transoesophageal echocardiographic automated border detection is sensitive to changes in preload, can predict fluid responsiveness, and can quantify the effects of volume expansion on cardiac output. It has potential clinical applications.

Non-invasive assessment of myocardial recovery on chronic left ventricular assist device: results associated with successful device removal

Background Myocardial recovery may occur in patients with heart failure who are receiving left ventricular assist-device support, but identification of candidates for device removal remains challenging. We hypothesized that on-line quantitative echocardiography during trials of decreased device support alone or in combination with exercise cardiopulmonary testing can assess cardiac recovery to predict successful device removal. Methods We studied 18 patients with severe heart failure, aged 45 ± 19 years, who received 234 ± 169 days of assist-device support as a bridge to transplantation. We used echocardiographic automated border detection from mid-ventricular short-axis images and non-invasive arterial pressure to measure beat-to-beat responses in 2 to 5 minute trials of decreased device flow. We also assessed maximal oxygen consumption in 14 patients who could exercise. Results Six patients experienced myocardial recovery and underwent successful device removal; 12 remained device dependent. With transient, low assist-device flow, patients with device removal had increased echocardiographic stroke area of 27% ± 36% vs −24% ± 12% ( p < 0.05) and fractional area change of 51% ± 13% vs 23% ± 11% ( p < 0.05) in the patients who were device dependent. Estimates of pre-load–adjusted maximal power, a relatively load-independent index, were 6.7 ± 2.1 mW/cm 4 in patients with successful device removal vs 1.2 ± 1.2 mW/cm 4 in patients who were device dependent ( p < 0.005). Maximal oxygen consumption was 17.2 ± 1.4 ml/kg/min in patients with myocardial recovery vs 13.1 ± 1.9 ml/kg/min in patients who were device dependent ( p < 0.005) and correlated with pre-load–adjusted maximal power ( r = 0.89, p < 0.001). Maximal oxygen consumption >16 ml/kg/min, increased stroke area, >40% increase in fractional area change, or pre-load–adjusted maximal power >4.0 mW/cm 4 with low device flow were associated with successful device removal ( p < 0.05). Conclusions On-line quantitative echocardiography alone or combined with exercise cardiopulmonary testing can assess myocardial recovery of patients receiving left ventricular assist-device support and has the potential to identify patients who are clinical candidates for device removal.

Assessment of cardiovascular dynamics by pressure-area relations in pediatric patients with congenital heart disease

Objectives: It is particularly useful to separately quantify the ventricular contractility and loading conditions for a better understanding of the cardiovascular dynamics in congenital heart disease, where abnormalities in chamber and loading properties may coexist. Furthermore, ventricular contractility and loading conditions may alter independently or simultaneously with disease progression and therapeutic intervention. The objectives of the present study were (1) to test whether ventricular pressure-area analysis can provide such quantitation among patients with various forms of congenital heart disease, (2) to reveal basal cardiovascular interaction in congenital heart disease by means of pressure-area analysis, and (3) to test the feasibility of this method in a simplified and less invasive form to further enhance its clinical value. Methods: We constructed pressure-area loops during caval occlusion by using transthoracic echocardiographic automated border detection combined with ventricular pressure recordings in 59 pediatric patients with congenital heart disease and in 7 normal control subjects. Results: Area measurements obtained by automated border detection were highly reproducible, and area changes reflected volume changes. The pressure-area data provided load-independent measures of contractility, which were consistently increased by use of dobutamine ( P < .05). End-systolic and arterial elastance individually quantified simultaneous changes in ventricular contractility and loading with milrinone infusion and predicted net cardiac performance. The pressure-area analysis better characterized the ventricular contractile states under a variety of loading conditions in congenital heart disease, whereas predominant load dependence of conventional indices confounded them. Furthermore, pressure-area relations were reasonably estimated from a single beat and from aortic pressure data during abdominal compression. Conclusions: Pressure-area analysis should provide a useful modality with which to assess cardiovascular dynamics in pediatric patients with congenital heart disease in more detail and should thus help improve the management of patients with this disease.

Electroconvulsive therapy impairs systolic performance of the left ventricle.

In this observational study, we examined left ventricular systolic performance during electroconvulsive therapy (ECT), using an echocardiographic automated border detection system. Nine ASA I or II patients scheduled for ECT were studied. Bilateral ECT was performed after the administration of propofol 1 mg x kg(-1), succinylcholine 1 mg x kg(-1), and assisted mask ventilation with 100% oxygen. Cardiac function was monitored by transthoracic echocardiography, prior to anesthesia induction and throughout the ECT procedure until ten minutes after the seizure. Increased end-systolic area and decreased fractional area change were observed at one minute after the seizure compared to the awake condition. No regional wall motion abnormalities were observed in all patients both at baseline condition and during the ECT CONCLUSION: Systolic performance of the left ventricle estimated by echocardiography decreased transiently in the immediate period after the electric shock.

Recovery of LV contractility in man is enhanced by preischemic administration of enflurane

Background. Volatile anesthetics enhance postischemic functional recovery in animal models; this effect has not been investigated in man.Methods. Twenty-two patients undergoing coronary surgery were randomized to enflurane administration (0.5% to 2%) for 5 minutes to reduce systolic blood pressure by 20% to 25% immediately before cardioplegic arrest. Left ventricular contractility was assessed by pressure-area relations using echocardiographic automated border detection during inflow occlusion before and after cardiopulmonary bypass. Linear regression analysis in 16 patients with paired data sets assessed changes in contractility.Results. The relation was highly linear (r = 0.95 ± 0.02). A change of slope versus the change in x intercept was detected in controls (mean difference, 16.1 mm Hg/cm2, 95% confidence limits, 5.9 to 26.3; 2.2 cm2, 95% confidence limits, −1.1 to 5.5; p = 0.007), which was different from those of treated patients (mean difference, 0.7 mm Hg/cm2, 95% confidence limits, −2.2 to 3.7; −0.06 cm2, 95% confidence limits, −1.6 to 1.5; p > 0.2). Analysis of covariance in the overall group confirmed a significant effect of treatment (p = 0.002).Conclusions. Enflurane enhances postischemic functional recovery, possibly through pharmacologic preconditioning of myocardium.

Load-Independent Indices of Left Ventricular Function Using Automated Border Detection.

Echocardiographic automated border detection is the ability to assess left ventricular (LV) cross-sectional cavity areas and volumes on line. This capability has enabled the use of LV pressure-volume relationships as a means to determine LV function in a manner relatively independent of loading conditions. This discussion reviews previous validation studies in animal models and humans using LV cross-sectional area as a surrogate for LV volume and the clinical applications of LV pressure-area relations. Applications of arterial pressure as a substitute for LV ejection pressure to assess pressure-area relations are also reviewed, along with the use of pressure-area relations to assess right ventricular performance. Last, preload-adjusted maximal power as an alternative load-insensitive means to determine LV performance is discussed.

Effects of Partial Left Ventriculectomy on Cardiac Performance

To the Editor: We read with great interest the recent article by Gorcsan et al.1 They report heterogeneous immediate effects of partial left ventriculectomy (PLV) on the slope (Ees) of end-systolic pressure-area relations obtained with echocardiographic automated border detection in 8 patients. The average change in Ees was from 6.5±3.4 mm Hg/cm2 (before PLV) to 4.3±2.5 mm Hg/cm2 (immediately after PLV) ( P =NS). The authors, however, overlooked an error made by the iterative linear regression technique that they used to calculate Ees. In the right bottom panel of the Figure, where the decreased Ees (1.1 mm Hg/cm2) was demonstrated after PLV, the end-systolic pressure-area …

Critical appraisal of left ventricular function assessment by the automated border detection method on echocardiography.: Is it good enough?

Many studies have attempted to validate the echocardiographic automated border detection (ABD) method for assessing left ventricular ejection fraction (LVEF) by comparing it with various echocardiographic and non-echocardiographic standards. The main basis of assessing its accuracy has been the coefficient of correlation. The fallacy of using coefficient of correlation for assessing agreement between two methods of measurement has been well emphasized in the literature. In the present study we used the Bland and Altman test for testing the accuracy of the ABD method. We compared the ABD method for LVEF assessment with the manual edge detection technique on echocardiography and with radionuclide ventriculography in 34 patients. The majority of patients (76%) had regional wall motion abnormality. The ABD method could be adequately performed in 25 (74%) patients. LVEF was significantly underestimated by the ABD method with very wide limits of agreement when compared with radionuclide ventriculography and the manual edge detection technique (−9.2±21.7 and −2.7±18.4 respectively, mean error±2 standard deviations). Stated simply, the ABD method could overestimate LVEF by 12.5 and 15.7 or underestimate by 30.9 and 21.1 when compared with radionuclide ventriculography and manual edge detection technique, respectively. This large error is by no means acceptable for clinical purposes. It is concluded that at the present stage, the ABD method cannot replace radionuclide ventriculography and manual edge detection technique for assessing LVEF.

Assessment of Left Ventricular Contractile State by Preload-Adjusted Maximal Power Using Echocardiographic Automated Border Detection

Objectives. We sought to assess the ability of preload-adjusted maximal power measured by echocardiographic automated border detection (ABD) to quantify left ventricular (LV) contractility by determining the effects of alterations in preload, afterload and contractile state.Background. Preload-adjusted maximal power can reflect LV contractile state relatively independent of changes in loading conditions.Methods. Eight anesthetized dogs had placement of aortic electromagnetic flow probes, LV and arterial pressure catheters and inferior vena caval (IVC) occluders; four had placement of thoracic aortic balloon occluders. Echocardiographic ABD measures of cross-sectional area were used as a surrogate for LV volume, and flow was estimated as the first derivative of area with respect to time. Power was calculated as the product of flow and pressure.Results. Preload independence during vena caval occlusions was achieved by preload adjustment (÷[end-diastolic area]3/2). Afterload independence was demonstrated by preload-adjusted maximal power being unaffected by acute increases in LV systolic pressure induced by aortic occlusion. ABD preload-adjusted maximal power reflected changes in contractile state: increasing with dobutamine infusion from 36 ± 14 to 70 ± 15 mW/cm4(p < 0.05 vs. control) and decreasing with propranolol infusion from 35 ± 13 to 17 ± 7 mW/cm4(p < 0.05 vs. control). These changes were significantly correlated with calculations of preload-adjusted maximal power using aortic flow (r = 0.90, SEE 10.5 mW/cm4) and load-independent measures of end-systolic elastance from pressure–area loops (r = 0.90, SEE 10.6 mW/cm4). Calculations of normalized preload-adjusted maximal power using arterial pressure were also closely correlated with similar calculations using LV pressure (r = 0.99, SEE 3%).Conclusions. Preload-adjusted maximal power using echocardiographic ABD can predict LV contractile state relatively independent of loading conditions and has potential for clinical application.

Right Ventricular Performance and Left Ventricular Assist Device Filling

Background. Right ventricular (RV) function is believed to be an important determinant of left ventricular assist device (LVAD) filling. This study was designed to demonstrate this relation in patients.Methods. To demonstrate the interaction between RV ejection and LVAD filling, 10 patients (mean age, 49 ± 13 years) supported with an LVAD were studied. Right ventricular pressure–area loops from cross-sectional area using transesophageal echocardiographic automated border detection and high-fidelity RV pressure were recorded simultaneously with LVAD volume during intraoperative inferior vena cava occlusion. Beat-by-beat RV ejection phase indices were calculated: stroke area, peak ejection rate, and stroke work. The LVAD filling rate was calculated as the first derivative of the volume, and the peak filling rate and the mean filling rate during RV systole were determined for each cardiac cycle.Results. Right ventricular stroke area, peak ejection rate, and stroke work were closely correlated with LVAD peak filling rate (r = 0.87 ± 0.09, r = 0.83 ± 0.09, and r = 0.85 ± 0.10, respectively). Also, baseline LVAD mean filling rate correlated with RV stroke work (r = 0.77) and LVAD peak filling rate with RV peak ejection rate for the group (r = 0.75).Conclusions. These correlations demonstrate predictable associations of RV ejection with LVAD filling.(Ann Thorac Surg 1997;63:1044–9)

Comparison of echocardiographic acoustic quantification system and radionuclide ventriculography for estimating left ventricular ejection fraction: Validation in patients without regional wall motion abnormalities

Echocardiographic automated border detection of blood-endocardium interface is made on the basis of the principle of acoustic quantification. The automated border system is capable of providing on-line left ventricular (LV) cavity area and function. Recently, ABD algorithms have been devised to estimate LV volume on line from a long-axis image, calculated by established area-length method or Simpson's formula. To test the clinical validity of this newly developed echocardiographic method, LV volumes and ejection fraction measured by real-time acoustic quantification were compared with radionuclide ejection fraction in 24 subjects on the same day. Patients were included in the study if ≥75% of their endocardium was visualized with conventional two-dimensional echocardiography. Sixteen (66%) of 24 patients had a technically adequate conventional echocardiogram with a broad range of ventricular dimensions and systolic function. None of the study patients had regional wall motion abnormalities. Echocardiographic measurements were obtained from the LV apical four-chamber, long-axis view. Ejection fraction, determined by the acoustic quantification and by radionuclide ventriculography, showed a strong linear relation ( r = 0.92, standard error of the estimate = 4.4, p < 0.05). However, acoustic quantification overestimated the radionuclide ejection fraction with rather wide limits of agreement (3.8% ± 16.4%; bias ± 2 SD). Thus echocardiographic automated border detection technique is a reasonably accurate method for on-line assessment of LV function. (Am Heart J 1997;133:359-63.)

Left ventricular performance assessed by echocardiographic automated border detection and arterial pressure.

Automated echocardiographic measures of left ventricular (LV) cavity area are closely correlated with changes in volume and can be coupled with LV pressure (PLV) to construct pressure-area loops in real time. The objective was to rapidly estimate LV contractility from end-systolic relationships of cavity area (as a surrogate for LV volume) and central arterial pressure (Pa) (as a surrogate for PLV) in a canine model using automated algorithms. In eight anesthetized mongrel dogs, we simultaneously measured PLV, LV area, and Pa (fluid-filled catheter). End-systolic pressure-area relationships in terms of pressure-area elastance (E'es)] from pressure-area loops during inferior vena caval occlusions were determined during basal conditions (control), dobutamine infusion (5-10 micrograms.mg-1.min-1), and after bolus propranolol (2 mg/kg) with both PLV and Pa by semiautomated and automated iterative regression methods. E'es increased during dobutamine infusion and decreased after propranolol infusion in all animals and with all iterative methods. Estimates of Ees from Pa were closely correlated with E'es from PLV by both the semiautomated and automated methods (r = 0.93; P < 0.01). The relationship between E'es obtained from Pn for the two methods was also closely correlated. Although the automated methods displayed larger differences from the semiautomated iterative technique by Bland-Altman analysis, the change in E'es with all techniques during dobutamine infusion and after propranolol infusion was of similar magnitude and direction among the three techniques. Greater variability with the dobutamine runs was partially due to abnormally conducted ventricular beats that minimized the number of consecutive beats that could be used for these analyses. We conclude that on-line Pa recordings from fluid-filled catheters can be used with echocardiographic automated border detection to rapidly calculate E'es as a means to estimate LV contractility.

Clinical feasibility of echocardiographic automated border detection in monitoring left ventricular response to acute changes of preload in normal subjects.

Echocardiographic automated border detection (ABD) provides an instantaneous measurement of left ventricular (LV) volume and its rate of change. We tested the clinical feasibility of ABD in monitoring on-line LV response to acute changes in preload. We examined 20 healthy males in the supine position, with legs elevated, back in the supine position, 5 min after the inflation of blood pressure cuffs at the root of the four limbs, 5 min after the deflation of cuffs. End-diastolic and end-systolic LV volumes significantly increased with elevated legs and decreased during cuff inflation; ejection fraction remained unchanged. Peak filling and peak emptying rates did not change with elevated legs and increased significantly during cuff inflation. The values of LV parameters were stable in the three resting conditions, demonstrating a good reproducibility of the ABD technique. Our results demonstrate that ABD may be useful in clinical practice for monitoring on-line small acute changes in LV volume and function.

Assessment of preload-adjusted maximal power using echocardiographic automated border detection to assess alterations in left ventricular contractility: William A. Mandarino MS, Christine M. Mahler MS, Michael R. Pinsky MD, John Gorcsan III MD. University of Pittsburgh, Pittsburgh, PA

Assessment of preload-adjusted maximal power using echocardiographic automated border detection to assess alterations in left ventricular contractility: William A. Mandarino MS, Christine M. Mahler MS, Michael R. Pinsky MD, John Gorcsan III MD. University of Pittsburgh, Pittsburgh, PA

Assessment of diastolic left ventricular filling by echocardiographic automated border detection and comparison with radionuclide ventriculography

To determine whether indexes obtained from a newly developed echocardiographic automated border detection (ABD) technology provide a reliable estimate of left ventricular (LV) diastolic filling, ABD variables of LV filling were compared with volumetric measurements determined by radionuclide angiography. Forty-two patients with a variety of heart diseases (age range, 11 to 76 years) underwent ABD echocardiographic studies on the same day as the radionuclide examination. Technically adequate ABD data could be obtained in 31 patients (74%). Nineteen healthy subjects served as normal controls. Area-time and volume-time waveforms for echocardiographic measurements were obtained from LV short-axis views at the level of the papillary muscles and four-chamber apical views. Both the diastolic indexes derived from the waveform of area change (short-axis view) and volume change (four-chamber apical view) correlated with radionuclide variables. Values measured from the ABD area-time waveform showed the following correlations: peak filling rate ( r = 0.86; standard error of the estimate [SEE] = 0.62), time to peak filling rate ( r = 0.85; SEE = 23.11), rapid filling phase fractional change ( r = 0.79; SEE = 5.51), and atrial filling phase fractional change ( r = 0.71; SEE = 5.82). Correlations of indexes derived from the ABD volume-time waveform were as follows: peak filling rate ( r = 0.87; SEE = 0.50), time to peak filling rate ( r = 0.90; SEE = 22.03), rapid filling fractional change ( r = 0.83; SEE = 5.33), and atrial filling fractional change ( r = 0.77; SEE = 4.68). ABD LV filling parameters in patients with heart disease and normal control subjects were significantly different. Thus ABD data from short-axis and apical views have a strong linear relation with radionuclide ventriculographic measurements and may be used as a method to assess LV diastolic filling.

Left ventricular pressure-volume relations with transesophageal echocardiographic automated border detection: Comparison with conductance-catheter technique

Pressure-volume relations are important means used to assess left ventricular (LV) contractility; however, on-line volume acquisition has been limited to the invasive conductance catheter. The objective was to compare simultaneous measures of LV volume by transesophageal echocardiographic automated border detection (ABD) and conductance catheter and their respective pressure-volume relations during steady state and alterations in preload and contractility. Seven dogs had placement of high-fidelity pressure and conductance catheters, a vena caval balloon occluder, and a transesophageal probe. An automated Simpson's rule volume algorithm was used from the transverse four-chamber view. Inotropic modulation was induced with dobutamine in four dogs and propranolol in three. Relative changes in ABD volume were linearly related to conductance volume at steady state with group mean r = 0.93 ± 0.03, standard error of estimate (SEE) = 10 ± 2%. Changes in end-diastolic volume, end-systolic volume, and stroke work with caval occlusion were also significantly correlated: r = 0.93 ± 0.04, SEE = 3.6 ml; r = 0.89 ± 0.04, SEE = 3.8 ± 1.9 ml; and r = 0.86 ± 0.05, SEE = 40 ± 21 mJ, respectively. The overall bias was for absolute ABD volume to be less. Endsystolic and maximal elastance values by ABD were significantly higher than by the conductance method; baseline group average 4.97 ± 0.92 mm Hg/ml versus 2.70 ± 1.15 mm Hg/ml and 6.63 ± 1.66 mm Hg/ml versus 3.20 ± 1.37 mm Hg/ml (p < 0.05), respectively. However, the direction and relative magnitude of changes in elastance with inotropic modulation were similar.

RIGHT VENTRICULAR PERFORMANCE AND LEFT VENTRICULAR ASSIST DEVICE FILLING

Mandarino, W A; Winowich, S; Gorcsan, J III; Gasior, T A; Pham, S; Griffith, B P; Kormos, R L Author Information

Automated echocardiographic measures of right ventricular area as an index of volume and end-systolic pressure-area relations to assess right ventricular function.

On-line determination of right ventricular (RV) volume to assess its function is clinically difficult. Echocardiographic automated border detection measures of left ventricular (LV) cavity area have been shown to reflect changes in volume, and pressure-area relations have been used to estimate LV contractility. The potential for RV cavity area to estimate changes in volume and to assess RV function, however, has not been evaluated. Accordingly, the objective of this study was to determine the relation between echocardiographic automated border-detected RV cross-sectional area and true volume and to assess the potential for end-systolic pressure-area relations to estimate RV function in an isovolumically contracting isolated canine heart preparation. Eight excised dog hearts with both right and left intraventricular balloons were perfused in an ex vivo apparatus in which both ventricular volumes were controlled independently. RV area data from the level of the left midventricular short-axis plane and pressure data were recorded on a computer through a customized hardware and software interface with the ultrasound system. RV volumes were varied from 9.4 +/- 3.9 to 43.8 +/- 6.9 mL at each of three different LV volume ranges (low range, 12.5 +/- 3.8 mL; medium range, 23.9 +/- 5.6 mL; and high range, 37.5 +/- 5.4 mL). The variation of RV area during isovolumic contraction, which we called deformational area change, was considerable (1.49 +/- 0.68 cm2 mean +/- SD) but did not change significantly with changing RV and LV volumes. Linear regression analysis correlated the maximum, minimum, and mean automated border-detected RV area during isovolumic contraction with absolute volume. A predominantly linear relation was observed, with the group mean r = .98 (y = 0.16x + 0.97; SEE = 0.21 cm2). The effect of LV volume on RV area-volume relation was a significant parallel downward shift (P < .05) by increases in LV volume. End-systolic pressure-area and pressure-volume relations using simultaneously RV pressure were both highly linear and covaried with changing LV volume. Echocardiographic automated border-detected RV area reflects changes in RV volume under a constant LV volume, and the derived end-systolic pressure-area relation has potential for on-line assessment of RV function.

Estimation of left ventricular function in patients with a left ventricular assist device.

Patients with profound left ventricular (LV) dysfunction supported by a left ventricular assist device (LVAD) may have recovery of LV function, but current methods for assessing this are difficult or not readily available. A new method to estimate LV performance was tested in 6 patients on LVAD (age, 47 +/- 12 years). Simultaneous measures of LV cross-sectional area (substitute for volume) using transesophageal echocardiographic automated border detection and femoral arterial pressure (substitute for LV ejection pressure) were recorded during brief periods on and off LVAD. During the LVAD off period, femoral arterial pressure and LV area signals were combined on-line to generate arterial pressure-LV area loops. The slope of the linear regression line connecting the end systolic points generated during LV filling after LVAD off was used as an estimate of end systolic elastance denoted by Ees. The average Ees was 3.8 +/- 3.1 mmHg/cm2. These values are significantly lower than those of 13 control patients (22.3 +/- 15.4 mmHg/cm2). This method of estimating Ees may be clinically useful in assessing LV recovery in patients on LVAD after extended support.