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Improvement of Ultrasonic Myocardial Properties after Aortic Valve Replacement for Pure Severe Aortic Stenosis: The Predictive Value of Ultrasonic Tissue Characterization for Left Ventricle Reverse Remodeling

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Improvement of Ultrasonic Myocardial Properties after Aortic Valve Replacement for Pure Severe Aortic Stenosis: The Predictive Value of Ultrasonic Tissue Characterization for Left Ventricle Reverse Remodeling
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  Improvement of Ultrasonic Myocardial Properties after Aortic Valve Replacement for Pure Severe AorticStenosis: The Predictive Value of Ultrasonic TissueCharacterizationforLeftVentricleReverseRemodeling Marcin Fijalkowski, MD, PhD, Andrzej Koprowski, MD, PhD, Rafal Galaska, MD, PhD,Marcin Gruchala, MD, PhD, Rafal Pawlaczyk, MD, PhD, Maciej Brzezinski, MD, PhD, Jan Rogowski, MD, PhD,and Andrzej Rynkiewicz, MD, PhD, FESC, FACC,  Gdansk, Poland  Background:  Aortic stenosis leads to left ventricular hypertrophy and accumulation of fibrillar collagens. Theanalysis of integrated backscatter (IBS) parameters provides information on ultrasonic myocardial properties. Methods:  The study population consisted of 58 patients with aortic stenosis. They were followed up for anaverage 18  6  5 months after aortic valve replacement (AVR). Traditional transthoracic echocardiographyand analysis of IBS reflectivity were performed before AVR and during the control visit after AVR. Results:  Asignificantreductioninleftventricularmassindex,asignificantincreaseinthemeancyclicvariationof IBS, and a decrease in absolute end-diastolic IBS intensity were observed after AVR. Conclusions:  These data suggest improvements in ultrasonic myocardial properties after AVR. PreoperativeanalysisofIBSparametersmightprovideadditionalinformationforpredictingleftventricularreverseremodelingin patients a mean of 1.5 years after AVR for aortic stenosis. (J Am Soc Echocardiogr 2010;23:1060-6.) Keywords:  Aortic stenosis, Ultrasonic tissue characterization, Left ventricular reverse remodeling Aortic stenosis (AS) is a common valvular heart disease associated with life-threatening complications and a high mortality rate insymptomatic patients in its natural history. 1,2 Pressure overload inpatients with AS leads to left ventricular (LV) hypertrophy associated with deposits of new sarcomeres and the accumulationof fibrillar collagens throughout the free wall and interventricularseptum of the heart. Myocardial fibrosis has been shown toincrease myocardial stiffness and to promote abnormalities of diastolic and systolic cardiac function and intramyocardialperfusion. 3 Although aortic valve replacement (AVR) dramatically improves the clinical courses of patients with AS by relieving thehigh-pressure aortic gradient, many factors affecting LV remodelingafter AVR are still unknown. 4 Ultrasonic myocardial tissue characterization by integratedbackscatter (IBS) has been successfully used for the differentiationof various myopathies from normal myocardium. 5,6 The analysis of IBS indices provides informat ion on myocardial fibrosis andultrasonic myocardial properties. 7,8 A number of experimental andclinical studies have shown that IBS characterization of myocardialtexture correlates with tissue collagen and water content and withthe degree of myocardial hypertrophy in patients withhypertension, but there is no strong evidence of the usefulness of IBS in patients with AS. 9,10 The aim of this study was to assess the diagnostic and prognostic value of different parameters of IBS measurement in relation to LV reverse remodeling and systolic and diastolic LV function changesfollowing AVR in patients with AS. METHODS Seventy-threeconsecutivesymptomaticpatientswithisolatedASandclinical and hemodynamic indications for AVR surgery according toAmerican College of Cardiology, American Heart Association, andEuropeanSocietyofCardiologyguidelineswereenrolledinthestudy.Exclusion criteria were mitral valve disease, more than mild aorticregurgitation, medical history of myocardial infarction, chronic atrialfibrillation, and malignant or accelerated arterial hypertension.Fifteen patients did not undergo the post-AVR follow-up examina-tion, because of new atrial fibrillation, pacemaker rhythm (rhythmother than sinus rhythm), and prosthesis dysfunction. They wereexcluded from further analysis. The final study population consistedof 58 patients (40 men, 18 women; mean age, 68 6 10 years). Themean follow-up period after AVR surgery was 18 6 5 months. AVR was performed in the Cardiosurgery Department of the Medical From the First Department of Cardiology (M.F., A.K., R.G., M.G., A.R.), and theCardiosurgery Department (R.P., M.B., J.R.), Medical University of Gdansk,Gdansk, Poland.This study was supported by grant 2 P05B 099 27 from the Polish Ministry of Science and Higher Education. Address reprint requests to Marcin Fijalkowski, MD, PhD, Medical University of Gdansk, First Department of Cardiology, ul Debinki 7, 80-211 Gdansk, Poland(E-mail:  mfijalkowski@gumed.edu.pl   ).0894-7317/$36.00Copyright 2010 by the American Society of Echocardiography.doi:10.1016/j.echo.2010.07.018 1060  University of Gdansk. Thirty-three biologic and 25 mechani-cal prostheses were implanted(mean label size, 23 6 2 mm).Traditional transthoracic echo-cardiography and measurement of IBS parameters were per-formed before AVR. The follow-up examination was performedduring the control visit with thesame echocardiographic settingsas in the initial study, on average1.5 years after AVR. The study protocol was approved by theethics committee of the MedicalUniversityofGdansk,andwritteninformed consent was obtainedfrom all patients. EchocardiographicEvaluation All patients underwent two-dimensional and Doppler echo-cardiography. Recordings andmeasurements were obtained ac-cording to the recommendationsof the American Society of Echocardiography. 11 Measure-ments of LV end-diastolic diame-ter, interventricular septal thick-ness, and posterior wall thickness were made at the beginningof the QRS complex. LV mass(LVM) was calculated usingDevereux’s formula andnormalized to body surfacearea as the LVM index (LVMI).LV hypertrophy was consideredto be present when LVMI was >116 g/m 2 in men and>104 g/m 2 in women. 12 Relative wallthickness(RWT)wasdefinedas the ratio (2    posterior wallthickness)/LVend-diastolicdiame-ter, and values # 0.43 were con-sidered normal. Patterns of LV remodeling in patients with AS wereclassifiedaccordingtoLVMIandRWTvaluesasnormalLVMandgeom-etry(LVMI<116g/m 2 inmen,LVMI<104g/m 2 inwomen,andRWT<0.43),concentricremodeling(LVMI<116g/m 2 inmen,LVMI<104g/m 2 inwomen,andRWT>0.43),concentrichypertrophy(LVMI>116g/m 2 in men, LVMI > 104 g/m 2 in women, and RWT > 0.43), and ec-centric hypertrophy (LVMI > 116 g/m 2 in men, LVMI > 104 g/m 2 in women, andRWT < 0.43). 12 Forthe purpose ofthis study, we definedreverseLVremodeling asthechange ofpreoperativetypeofLVremod-eling by at least one pattern toward normal LVM and geometry. Systolic LV Function  We assessed LV systolic function by evaluation of ejection fraction(EF), fractional shortening (FS), midwall FS (mwFS), and circumferen-tial end-systolic wall stress (cESS). EF was measured using the biplaneSimpson’s method, and mwFS was calculated using a previously  validated formula by de Simone  et al. 13 Circumferential end-systolic wall stress was estimated at the LV midwall level using a cylindricalmodel described by Gaasch  et al. 14 adjusted to the intraventricularLV pressure at the end of systole, which was calculated as a sum of the cuff systolic blood pressure and maximal Doppler-driventransvalvular gradient through stenotic native valve or valve prosthe-sis after surgery. 15 Diastolic LV Function Doppler parameters of mitral inflowsuchas the mitral E and Awaves(early and late diastolic filling velocities), mitral E-wave decelerationtime, and the isovolumic relaxation time, were measured using pulseDoppler. Pulmonary venous flow measurements included peaksystolic velocity, peak diastolic velocity, and peak atrial reversal velocity. According to the Canadian consensus recommendationsfor the measurement and reporting of diastolic dysfunction by echocardiography, the following patterns of LV filling were classified:normal pattern of LV  filling, delayed relaxation, pseudonormal filling,and restrictive filling. 16 The average values of early mitral annular di-astolic velocity (e 0 ) were obtained from both the septal and lateralsites and averaged for further evaluation. Subsequently, the ratio of mitral peak velocity of early filling to early diastolic mitral annular velocity (E/e 0 ) was calculated. 17 Improvement of diastolic function was defined as the change of preoperative pattern of LV diastolicfunction by at least one pattern toward normal LV filling parameters.  AS Severity Assessment Peak and mean transaortic valve pressure gradients (PGs) and velocity-time integral (VTI) of transaortic velocity were measured us-ing continuous-wave Doppler from different windows. The highest  velocity was used for tracing the VTI. Effective aortic valve area(AVA)wascalculatedusingthe continuity equationand thenindexedto body surface area. The ratio of LVoutflow tract (LVOT) velocity totransaortic velocity wasalso calculated (VTI LVOT /VTI Ao ).Aortic valveprostheses were evaluated on the samebasis as native valves.Patient-prosthesis mismatch (PPM) was diagnosed when the effective orificearea (EOA) was <0.9 cm 2 /m 2 . Ultrasonic Tissue Characterization To assess IBS signal, two regions of interest were chosen in theparasternal long-axis view: the mid septum and the mid posterior wall. The mean value of IBS was acquired from the region of interest foreachimaged frame duringthe cardiac cycleand averaged forend-diastole and end-systole for all cardiac cycles throughout the cineloop. The absolute intensity of IBS at end-diastole (IBS ed ) and at end-systole (IBS es ) was obtained for both the septum and theposterior wall. The cyclic variation of IBS (CVIBS) was calculated asthe difference between end-diastolic and end-systolic values(CVIBS = IBS ed    IBS es ) for the septum and the posterior wall(Figure 1). Additionally, we calculated the index of CVIBS(CVIBS index ) at the septum and at the posterior wall, which werecalculated by use of the formula [(IBS ed    IBS es )/IBS ed ]    100. Adetailed IBS acquisition methodology was described previously. 9 Allexaminations were recorded on magneto-optical disks and analyzedoffline by experienced echocardiographers (M.F., A.K., and R.G.)using a Philips Sonos 5500 revision D.2 with a 3s transducer(Philips Medical Systems, Andover, MA) by means of a commercially available acoustic densitometry software package. According to  Abbreviations  AS = Aortic stenosis  AVA  = Aortic valve area  AVR = Aortic valvereplacement cESS = Circumferential end-systolic wall stress CVIBS = Cyclic variation of integrated backscatter CVIBS index  = Index of cyclicvariation of integratedbackscatter EF = Ejection fraction EOA  = Effective orifice area FS = Fractional shortening IBS = Integrated backscatter IBS ed  = Integratedbackscatter at end-diastole IBS es  = Integratedbackscatter at end-systole LV  = Left ventricular LVM = Left ventricular mass LVMI = Left ventricular massindex LVOT = Left ventricularoutflow tract mwFS = Midwall fractionalshortening PG = Pressure gradient PPM = Patient-prosthesismismatch ROC = Receiver operatingcharacteristic RWT = Relative wallthickness  VTI = Velocity-time integral  Journal of the American Society of Echocardiography  Volume 23 Number 10 Fijalkowski et al 1061  a previous study, a mean value of CVIBS > 6 dB was considerednormal. 6 The mean IBS parameters (mean CVIBS, mean IBS ed , andmean CVIBS index ) were defined as average values obtained fromboth the septum and the posterior wall. Additionally, we evaluatedthe sensitivity and specificity of preoperative mean IBS ed , meanCVIBS, and mean CVIBS index  different thresholds for LV reverseremodeling occurrence after aortic valve surgery. Differences of preoperative and postoperative values were also calculated for allparameters ( D ). Reproducibility Data of IBS Evaluation Fifteen randomly selected IBS evaluations were made twice by twoechocardiographerstoassessinterobserverandintraobservervariability.Agreement between two measurements was considered as 6 0.1 dB.Intraobserver and interobserver variability were good ( k  = 0.74 and  k = 0.67, respectively). Statistical Analysis Forthestatisticalanalysis,StatisticaforWindowsversion9.0(StatSoft,Tulsa, OK) was used. Continuous data are expressed as mean 6 SD.Paired  t   tests were used to compare preoperative and postoperativeparameters. One-way analysis of variance followed by Bonferroni’spost hoc test was used to assess the statistical difference betweenmore than two groups of continuous parameters. To measure thestrength of the relation between CVIBS and other echocardiographicparameters, Pearson’s correlation coefficient was calculated. The rela-tion between clinical improvement after AVR and echocardiographicparameters was evaluated using multiple logistic regression analysis.Receiveroperatingcharacteristic(ROC)curveanalysiswasgeneratedby MedCalc version 11.2.1 (http://www.medcalc.com) to test thepredictive discrimination of IBS parameters. A  p   value < .05 wasconsidered significant. The  k  statistic was used to assess intraobserverand interobserver variability for IBS measurements. RESULTS Before AVR Preoperativeandpostoperativeclinicaldataofthepatientsenrolledinthe study are outlined in Table 1.Echocardiographic preoperative and postoperative data obtainedduring the initial and follow-up examinations are outlined in Table2. Forty-three patients (74%) had LV hypertrophy (mean LVM, 262 6  88 g; mean LVMI, 143  6  45 g/m 2 ). There was no correlationbetween LV hypertrophy and echocardiographic parameters of ASseveritysuchasAVA,maximalPG,orVTI LVOT /VTI Ao .Theprevalenceof different LVremodeling patterns was as follows: normal geometry in three patients (5%), concentric remodeling in 20 patients (35%),concentrichypertrophy in28patients (48%),and eccentrichypertro-phy in seven patients (12%). There were no significant differences of AS severity parameters among particular patterns of LVremodeling.The prevalence of different patterns of LV diastolic dysfunction wasasfollows:normaldiastolicfunctionin11patients(20%),delayedrelaxation in 36 patients (62%), pseudonormal filling in six patients(10%), and restrictive filling in five patients (8%). There was no signif-icant difference of AS severity parameters in particular patterns of diastolic dysfunction. Figure 1  Example of IBS curve of a patient with AS obtained from the parasternal long-axis view. Table 1  Preoperative and postoperative clinical data  Variable Before AVR After AVR  P Heart rate (beats/min) 73 6 12 71 6 10 NSSystolic blood pressure (mm Hg) 130 6 14 141 6 18 <.05Diastolic blood pressure (mm Hg) 76 6 11 80 6 12 <.05Mean blood pressure (mm Hg) 94 6 12 101 6 13 <.05Weight (kg) 75 6 11 78 6 11 <.001Body mass index (kg/m 2  ) 26.6 6 2.9 27.9 6 3.3 <.001 1062 Fijalkowski et al  Journal of the American Society of Echocardiography October 2010   IBS.  The preoperative mean CVIBS was 5.8 6 1.7 dB, mean IBS ed  was 36.2  6  5.0 dB, and mean CVIBS index  was 17.1  6  5.0%.Significantly lower values of mean CVIBS before surgery wereobserved in the subgroup of patients with eccentric LV hypertrophy in comparison with patients with LV concentric remodeling or hyper-trophy. Additionally, significantly higher mean IBS ed  was observed inpatients with eccentric LV hypertrophy in comparison with patients withnormalLVManddimensions(Table3).Therewerenosignificant differencesofmeanIBSvaluesinpatientswithdifferentdiastolicfillingpatterns.However,inthesubgroupofpatientswithmeanCVIBS # 6dBbeforeAVRincomparisonwithsubjectswithmeanCVIBS>6dB,the initial maximal velocity of e 0  was significantly lower (6.9 6 2.5 vs8.3 6 2.0 cm/s,  P   < .05), and the E/e 0 ratio was significantly higher(13.0  6 7.2 vs 9.6 6 2.9,  P   < .05). Both CVIBS and CVIBS index  at theseptumandposteriorwallshowedpositivesignificantcorrelations withEF,FS,ande 0 andnegativesignificantcorrelationswithcESSandLVMI. There were no significant correlations between all evaluatedIBS indices and AVA or mean or maximal PG (Table 4).  After AVR  We observed significant reductions of LV diameter and thicknesses of both the septum and the posterior wall and significant reductions inLVM and LVMI. RWT did not change significantly after AVR. AfterAVR, we observed LVreverse remodeling due to AVR in 38 patients(65%; Figure 2A). Systolic echocardiographic parameters such as EF,FS, mwFS, and cESS significantly increased after AVR (Table 2).LV diastolic functional changes are shown in Figure 2B.Improvement of LV diastolic function was found in 20 patients(35%). The mean value of early diastolic mitral annular velocity (e 0 )significantly increased after AVR, and the E/e 0 ratio significantly decreased (Table 2).  IBS.  ThemeanCVIBSsignificantlyincreasedafterAVR(5.7 6 1.7vs7.2 6 1.4dB, P  <.0001),andthenumberofpatientswithmeanCVIBS> 6 dB increased from 23 (40%) before AVR to 47 (81%) after AVR.The mean IBS ed  significantly decreased after AVR (36.2  6  4.9 vs27.2 6 3.5 dB,  P   < .0001), and the mean CVIBS index  significantly in-creased after AVR (17.1  6  5.0% vs 37.7  6  10.5%,  P   < .0001)(Figure 3). We found a significant correlation between D cESS and the D  values of all mean IBS parameters, exceptionally high in the caseof   D  mean CVIBS index  ( r   =  0.86). Furthermore,  D e 0  was negatively significantly correlated with  D  mean IBS ed . We did not find any significant correlations between the D  values of all mean IBS parame-ters and D AVA or D mean PG (Table 5). Preoperative IBS as Predictive Values for LV ReverseRemodeling UsingROCcurveanalysis,weestablishedthediscriminatorypowerof differentcutpointsofmeanCVIBS,meanIBS ed ,andmeanCVIBS index for LVreverse remodeling after aortic valve surgery. For mean CVIBS,the area under the ROC curve was 0.81 (95% confidence interval,0.69–0.90; P  <.0001),andbyusingvaluesofCVIBS $ 5.1dBasacut-off point, patients were expected to have LVreverse remodeling withsensitivity of 84.6% and specificity of 63.1% (positive predictive value, 82%; negative predictive value, 67%). For mean IBS ed , thearea under the ROC curve was 0.86 (95% confidence interval,0.74–0.94;  P   < .0001), and by using values of mean IBS ed $ 34 dBasacutoffpoint,patientswereexpectedtohaveLVreverseremodeling with sensitivity of 84.6% and specificity of 78.9% (positive predictive value, 89%; negative predictive value, 72%). For mean CVIBS index ,the area under the ROC curve was 0.86 (95% confidence interval,0.76–0.94;  P   < .0001), and by using values of mean CVIBS index  $ 15.7% as a cutoff point, patients were expected to have LVreverse re-modeling with sensitivity of 79.5% and specificity of 84.2% (positivepredictive value, 91%; negative predictive value, 67%). The areasunder the ROC curves for mean CVIBS, mean IBS ed , and meanCVIBS index  did not significantly differ (Figure 4). EOA of Aortic Valve Prosthesis Onaverage,thevalveEOAincreasedby0.53 6 0.24cm 2 /m 2 ,andthemean postoperative EOAwas 1.6 6 0.6 cm 2 . In our study group, 35patients(60%)hadPPM.Weobservedsignificantlysmallermagnitudes Table 2  Preoperative and postoperative echocardiographicdata  Variable Before AVR After AVR  P IVSd (mm) 14 6 3 13 6 2 <.001LVDd (mm) 47 6 9 44 6 6 <.001PWd (mm) 13 6 2 12 6 2 <.001LVDs (mm) 31 6 10 27 6 6 <.001RWT 0.59 6 0.17 0.55 6 014 NSLVEF (%) 72 6 13 77 6 9 <.05FS (%) 36 6 9 40 6 8 <.05mwFS (%) 12.2 6 3.1 14.1 6 3.1 <.001cESS (kdyne/cm 2  ) 207 6 52 165 6 32 .001E (cm/s) 77 6 23 85 6 24 <.05 A (cm/s) 86 6 34 89 6 27 NSE/A 1.2 6 1.0 1.1 6 0.6 NSDT (ms) 250 6 95 254 6 78 NSS (cm/s) 53 6 16 62 6 15 <.001D (cm/s) 41 6 16 45 6 12 NSS/D 1.5 6 0.6 1.5 6 0.5 NS Ar (cm/s) 29 6 6 28 6 6 NSe 0 (cm/s) 7.4 6 2.4 9.6 6 2.0 <.05E/e 0 11.6 6 6.1 9.3 6 3.5 <.001Maximal PG (mm Hg) 87 6 13 34 6 22 <.001Mean PG (mm Hg) 56 6 22 19 6 14 <.001 AVA (cm 2  ) 0.7 6 0.3 1.6 6 0.6 <.001 AVA index (cm 2  /m 2  ) 0.4 6 0.1 0.8 6 0.3 <.001VTI LVOT  /VTI  Ao  0.24 6 0.1 0.48 6 0.1 <.001LVM (g) 262 6 88 198 6 58 <.001LVMI (g/m 2  ) 143 6 45 106 6 29 <.001 DT  , Deceleration time;  IVSd  , interventricular septal thickness;  LVDd  ,LVend-diastolicdiameter; LVDs ,LVend-systolicdiameter; LVEF  ,LVejection fraction;  PWd  , posterior wall thickness. Table 3  Mean CVIBS, mean IBS ed , and mean CVIBS index  indifferent patterns of LV remodeling before AVR  Variable NG CR CH EH Mean IBS ed  (dB) 32.4 6 3.3 36.2 6 4.8 36.8 6 5.2 41.2 6 4.7*Mean CVIBS (dB) 6.4 6 1.6 6.3 6 1.7 5.7 6 1.7 3.9 6 1.8 † MeanCVIBS index  (%)17.2 6 2.9 18.7 6 5.4 16.9 6 4.7 12.9 6 4.9 CH ,Concentrichypertrophy; CR ,concentricremodeling; EH ,eccen-tric hypertrophy;  NG , normal LVM and geometry.* P  < .05 for EH vs NG.† P  < .05 for EH vs CR and for EH vs CH.  Journal of the American Society of Echocardiography  Volume 23 Number 10 Fijalkowski et al 1063  of regressionof LMVand LMVI inthesubgroup of patientswith PPM(42 6 58vs98 6 78g, P  <.05,and25 6 32vs56 6 40g/m 2 , P  <.05,respectively). We did not find any significant influence of PPM on any postoperative IBS values or D IBS parameters. DISCUSSION The main findings of our study are as follows: (1) preoperative meanCVIBS was the lowest and mean IBS ed  was the highest in patients with eccentric LV hypertrophy before AVR; (2) both mean CVIBSand mean CVIBS index  showed positive significant correlations withEF, FS, and e 0 and negative significant correlations with cESS andLVMI; (3) mean CVIBS and mean CVIBS index  significantly increasedand mean IBS ed  significantlydecreasedafter AVR;and (4) therewererelatively high positive and negative predictive values of different cut points of IBS parameters for LVreverse remodeling after AVR.The ultrasonic myocardial characterization by backscatter signalhas been studied in patients with hypertension, cardiomyopathies,and coronary artery disease. 10,18 Ultrasonic tissue characterizationby CVIBS was evaluated in congenital AS in children. 19 Accordingto our knowledge, only one study has examined changes in myocar-dial ultrasonic characterization after AVR surgery in adult patients with LV pressure overload: Di Bello  et al. 20 evaluated the impact of surgery on ultrasonic tissue reflectivity in LV pressure overload but  withnorelationtoLVremodelingandinasmallernumberofsubjects.A close correlation has been described between cardiac functionand myocardial morphology with myocardial fibrosis and LV end-diastolic pressure increase in patients with AS. 20,21 Myocytehypertrophy and reactive fibrosis are the first maladaptive changesto LV pressure overload in patients with AS. 20,22 Reduction of capillary density, myocardial cellular loss, and replacement fibrosiscomplete this mechanism. These changes in myocardial texturemight be reflected by changes in IBS measurements. The increaseof the myocardial collagen network could determine an increase inscattering. Additionally, pressure overload in AS might causechanges in the muscle fibers’ orientation, influencing myocardialacoustic properties. 23 A normal myocardium shows a cardiaccycle–dependent variation of IBS, which reflects its intrinsic contrac-tile performance. The end-diastolic peak value of IBS in humans isdirectly related to the myocardial collagen content. 20 This observa-tion was sustained in our study by the fact that mean CVIBS wasthe lowest and mean IBS ed  was the highest in patients with eccentrichypertrophy, the most advanced phase of myocardial remodelingdue to pressure overload. The preoperative higher cESS, lower EF,and lower velocity of the e 0  wave correlated with the diminishedmyocardial ultrasonic properties before AVR. End-systolic stress, amajor determinant of overall LV performance, can be considered asthe measurement of the afterload that limits ventricular fiber shorten-ing at end-ejection. 14 It reflects the combined effects of peripheralloading conditions and LV chamber pressure, dimensions, and wallthickness. In our study, we observed a significant reduction of cESSthat was significantly correlated with changes of IBS parameters,particularly significant with CVIBS index  changes due to aortic valve surgery. These observations support the hypothesis that CVIBSorCVIBS index  couldbe considered amanifestation ofintrinsicmyocardial contractility that is relatively sensitive to afterloadconditions. Table 4  Correlation matrix (  R  values) of mean IBS and selected echocardiographic parameters  Variable EF FS mwFS cESS RWT LVMI AVA Mean PG e 0 Septal CVIBS 0.32* 0,26* 0.22   0.36* 0.04   0.34* 0.03 0.02 0.50* Posterior wall CVIBS 0.35* 0.28* 0.17   0.40* 0.12   0.27* 0.10 0.06 0.42* Mean CVIBS 0.36 * 0.29* 0.20   0.39* 0.04   0.34* 0.08 0.05 0.48* Septal IBS ed  0.22 0.20 0.21   0.14   0.05   0.01 0.06 0.00 0.19Posterior wall IBS ed  0.29* 0.26 0.22   0.24 0.00   0.09 0.05 0.05 0.29*Mean IBS ed  0.27* 0.24 0.22   0.21   0.01   0.12   0.01 0.02 0.25Septal CVIBS index  0.27* 0.20 0.17   0.26* 0.03   0.35*   0.07 0.02 0.49*Posterior wall CVIBS index  0.36* 0.29* 0.16   0.44* 0.17   0.37*   0.11 0.10 0.48*Mean CVIBS index  0.29* 0.23 0.17   0.32* 0.07   0.36*   0.08 0.08 0.50** P  < .05. Figure 2  Individual plot of LV remodeling patterns (A) and LV diastolic dysfunction (B) before and after AVR.  CH , Concentric hyper-trophy;  CR , concentric remodeling;  DR , delayed relaxation;  EH , eccentric hypertrophy;  NG , normal LVM and geometry;  NL , normaldiastolic function;  PF  , pseudonormal filling;  RF  , restrictive filling. 1064 Fijalkowski et al  Journal of the American Society of Echocardiography October 2010
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