Non-invasive assessment of left ventricular filling pressure in aortic stenosis.

BACKGROUND: The assessment of left ventricular (LV) filling pressure (FP) is important for the management of aortic stenosis (AS) patients. Although, it is often restricted for predict LV FP in AS because of mitral annular calcification and a certain left ventricular hypertrophy. Thus, we tested the predictive ability of the algorithm for elevated LV FP in AS patients and also applied a recently-proposed echocardiographic scoring system of LV FP, visually assessed time difference between the mitral valve and tricuspid valve opening (VMT) score. METHODS: We enrolled consecutive 116 patients with at least moderate AS in sinus rhythm who underwent right heart catheterization and echocardiography within 7 days. Mean pulmonary artery wedge pressure (PAWP) was measured as invasive parameter of LV FP. LV diastolic dysfunction (DD) was graded according to the ASE/EACVI guidelines. The VMT score was defined as follows: time sequence of opening of mitral and tricuspid valves was scored to 0-2 (0: tricuspid valve first, 1: simultaneous, 2: mitral valve first). When the inferior vena cava was dilated, one point was added and VMT score was finally calculated as 0-3. RESULTS: Of the 116 patients, 29 patients showed elevated PAWP. Ninety patients (93%) and 67 patients (63%) showed increased values for left atrium volume index (LAVI) and E/e', respectively when the cut-off values recommended by the guidelines were applied and thus the algorism predicted elevated PAWP with a low specificity and positive predictive value (PPV). VMT ≥ 2 predicted elevated PAWP with a sensitivity of 59%, specificity of 90%, PPV of 59%, and negative predictive value of 89%. An alternative algorithm that applied tricuspid regurgitation velocity and VMT scores was tested, and its predictive ability was markedly improved. CONCLUSION: VMT score was applicable for AS patients. Alternative use of VMT score improved diagnostic accuracy of guideline-recommended algorism.

Assessment of anthracycline-induced cardiotoxicity in childhood cancer survivors during long-term follow-up using strain analysis and intraventricular pressure gradient measurements.

BACKGROUND: Cardiac dysfunction due to cardiotoxicity from anthracycline chemotherapy is a leading cause of morbidity and mortality in childhood cancer survivors (CCS), and the cumulative incidence of cardiac events has continued to increase. This study identifies an adequate indicator of cardiac dysfunction during long-term follow-up. PROCEDURE: In total, 116 patients (median age: 15.5 [range: 4.7-40.2] years) with childhood cancer who were treated with anthracycline were divided into three age groups for analysis (C1: 4-12 years of age, C2: 13-18 years of age, C3: 19-40 years of age), and 116 control patients of similar ages were divided into three corresponding groups (N1, N2, and N3). Layer-specific strains were assessed for longitudinal strain (LS) and circumferential strain (CS). The total and segmental intraventricular pressure gradients (IVPG) were also calculated based on Doppler imaging of the mitral inflow using Euler's equation. RESULTS: Conventional echocardiographic parameters were not significantly different between the patients and controls. All layers of the LS and inner and middle layers of the basal and papillary CS in all ages and all IVPGs in C2 and C3 decreased compared to those of corresponding age groups. Interestingly, basal CS and basal IVPG in CCS showed moderate correlation and both tended to rapidly decrease with aging. Furthermore, basal IVPG and anthracycline dose showed significant correlations. CONCLUSIONS: Basal CS and total and basal IVPGs may be particularly useful indicators of cardiotoxicity in long-term follow-up.

Noninvasive assessment of left ventricular end-diastolic pressure using machine learning-derived phasic left atrial strain.

AIMS: While transthoracic echocardiography (TTE) assessment of left ventricular end-diastolic pressure (LVEDP) is critically important, the current paradigm is subject to error and indeterminate classification. Recently, peak left atrial strain (LAS) was found to be associated with LVEDP. We aimed to test the hypothesis that integration of the entire LAS time curve into a single parameter could improve the accuracy of peak LAS in the noninvasive assessment of LVEDP with TTE. METHODS AND RESULTS: We retrospectively identified 294 patients who underwent left heart catheterization and TTE within 24 h. LAS curves were trained using machine learning (100 patients) to detect LVEDP ≥ 15 mmHg, yielding the novel parameter LAS index (LASi). The accuracy of LASi was subsequently validated (194 patients), side by side with peak LAS and ASE/EACVI guidelines, against invasive filling pressures. Within the validation cohort, invasive LVEDP was elevated in 116 (59.8%) patients. The overall accuracy of LASi, peak LAS, and American Society of Echocardiography/European Association for Cardiovascular Imaging (ASE/EACVI) algorithm was 79, 75, and 76%, respectively (excluding 37 patients with indeterminate diastolic function by ASE/EACVI guidelines). When the number of LASi indeterminates (defined by near-zero LASi values) was matched to the ASE/EACVI guidelines (n = 37), the accuracy of LASi improved to 87%. Importantly, among the 37 patients with ASE/EACVI-indeterminate diastolic function, LASi had an accuracy of 81%, compared with 76% for peak LAS. CONCLUSION: LASi allows the detection of elevated LVEDP using invasive measurements as a reference, at least as accurately as peak LAS and current diastolic function guideline algorithm, with the advantage of no indeterminate classifications in patients with measurable LAS.

Assessment of Early Diastolic Intraventricular Pressure Difference in Children by Blood Speckle-Tracking Echocardiography.

BACKGROUND: The lack of reliable echocardiographic techniques to assess diastolic function in children is a major clinical limitation. Our aim was to develop and validate the intraventricular pressure difference (IVPD) calculation using blood speckle-tracking (BST) and investigate the method's potential role in the assessment of diastolic function in children. METHODS: Blood speckle-tracking allows two-dimensional angle-independent blood flow velocity estimation. Blood speckle-tracking images of left ventricular (LV) inflow from the apical 4-chamber view in 138 controls, 10 patients with dilated cardiomyopathies (DCMs), and 21 patients with hypertrophic cardiomyopathies (HCMs) <18 years of age were analyzed to study LV IVPD during early diastole. Reproducibility of the IVPD analysis was assessed, IVPD estimates from BST and color M mode were compared, and the validity of the BST-based IVPD calculations was tested in a computer flow model. RESULTS: Mean IVPD was significantly higher in controls (-2.28 ± 0.62 mm Hg) compared with in DCM (-1.21 ± 0.39 mm Hg, P < .001) and HCM (-1.57 ± 0.47 mm Hg, P < .001) patients. Feasibility was 88.3% in controls, 80% in DCM patients, and 90.4% in HCM patients. The peak relative negative pressure occurred earlier at the apex than at the base and preceded the peak E-wave LV filling velocity, indicating that it represents diastolic suction. Intraclass correlation coefficients for intra- and interobserver variability were 0.908 and 0.702, respectively. There was a nonsignificant mean difference of 0.15 mm Hg between IVPD from BST and color M mode. Estimation from two-dimensional velocities revealed a difference in peak IVPD of 0.12 mm Hg (6.6%) when simulated in a three-dimensional fluid mechanics model. CONCLUSIONS: Intraventricular pressure difference calculation from BST is highly feasible and provides information on diastolic suction and early filling in children with heart disease. Intraventricular pressure difference was significantly reduced in children with DCM and HCM compared with controls, indicating reduced early diastolic suction in these patient groups.

Noninvasive Assessment of Left Ventricular Pressure-Volume Relations: Inter- and Intraobserver Variability and Assessment Across Heart Failure Subtypes.

A novel method to derive pressure-volume (PV) loops noninvasively from cardiac magnetic resonance images has recently been developed. The aim of this study was to evaluate inter- and intraobserver variability of hemodynamic parameters obtained from noninvasive PV loops in healthy controls, subclinical diastolic dysfunction (SDD), and patients with heart failure with preserved ejection fraction, mildly reduced ejection fraction, and reduced ejection fraction. We included 75 subjects, of whom 15 were healthy controls, 15 subjects with SDD (defined as fulfilling 1 to 2 echocardiographic criteria for diastolic dysfunction), and 15 patients with preserved ejection fraction, 15 with mildly reduced ejection fraction, and 15 with reduced ejection fraction. PV loops were computed using time-resolved left ventricular volumes from cardiac magnetic resonance images and a brachial blood pressure. Inter- and intraobserver variability and intergroup differences of PV loop-derived hemodynamic parameters were assessed. Bias was low and limits of agreement were narrow for all hemodynamic parameters in the inter- and intraobserver comparisons. Interobserver difference for stroke work was 2 ± 9%, potential energy was 4 ± 11%, and maximal ventricular elastance was -4 ± 7%. Intraobserver for stroke work was -1 ± 7%, potential energy was 3 ± 4%, and maximal ventricular elastance was 1 ± 5%. In conclusion, this study presents a fully noninvasive left ventricular PV loop analysis across healthy controls, subjects with SDD, and patients with heart failure with preserved or impaired systolic function. In conclusion, the method for PV loop computation from clinical-standard manual left ventricular segmentation was rapid and robust, bridging the gap between clinical and research settings.

Left Ventricular Pressure Volume Assessment Using Carotid Artery Access in the Rat.

Left ventricular (LV) catheterization with either a pressure catheter or pressure-volume catheter provides a means to measure cardiac function, an important endpoint in many studies including cardiac gene therapy. While the catheter can be inserted directly into the heart using a surgical approach, utilizing the carotid artery for access has the advantage of being a closed-chest procedure. This negates the need for intubation, prevents myocardial trauma, and preserves normal intrathoracic pressure, providing more accurate assessments of cardiac physiology parameters. We describe a protocol for obtaining carotid artery access and insertion of a pressure-volume catheter into the LV of rodents.

Non-invasive assessment of left ventricular relaxation property using color M-mode-derived intraventricular pressure gradients in cats.

INTRODUCTION: Diastolic dysfunction is an early clinical feature of feline hypertrophic cardiomyopathy (HCM). The left ventricular filling in early diastole is facilitated by the diastolic intraventricular pressure gradient (IVPG). The study objectives were to evaluate color Doppler M-mode-derived IVPG calculation in cats as a non-invasive assessment of the left ventricular relaxation property to determine the normal ranges of peak IVPG in cats and investigate the influence of left ventricular function and heart rate (HR). ANIMALS: One hundred and six client-owned apparently healthy cats. METHODS: Prospective cross-sectional study. Quantitative analysis of color Doppler M-mode images was used to estimate total and segmental IVPGs non-invasively. RESULTS: The total IVPG was 0.76 mmHg (95% reference interval (RI): 0.28-1.29 mmHg), the basal IVPG 0.34 mmHg (95% RI: 0.07-0.63 mmHg), and the mid-apical IVPG 0.42 mmHg (95% RI: 0.15-0.71 mmHg). Total and segmental IVPG increased with HR (P < 0.003), while segmental percent IVPG was HR independent. A short isovolumic relaxation time (IVRT) and a high mitral annular velocity in early diastole were associated with an increase in total IVPG (P = 0.008 and P = 0.009, respectively) adjusted for HR. An increase in IVPG was associated with an increase in mitral inflow velocity (P < 0.001). CONCLUSIONS: Feline IVPGs increase with HR and a short IVRT, which was believed to be a normal physiologic adrenergic response associated with an increased sympathetic tone. Future studies of segmental IVPG changes in feline HCM are needed to evaluate the clinical applicability of color Doppler M-mode estimated IVPGs in feline cardiology.

Impact of coronary artery disease on contractile function and ventricular-arterial coupling during exercise: Simultaneous assessment of left-ventricular pressure-volume and coronary pressure and flow during cardiac catheterization.

Coronary artery disease (CAD) can adversely affect left ventricular (LV) performance during exercise by impairment of contractile function in the presence of increasing afterload. By performing invasive measures of LV pressure-volume and coronary pressure and flow during exercise, we sought to accurately measure this with comparison to the control group. Sixteen patients, with CCS class >II angina and CAD underwent invasive simultaneous measurement of left ventricular pressure-volume and coronary pressure and flow velocity during cardiac catheterization. Measurements performed at rest were compared with peak exercise using bicycle ergometry. The LV contractile function was measured invasively using the end-systolic pressure-volume relationship, a load independent marker of contractile function (Ees). Vascular afterload forces were derived from the ratio of LV end-systolic pressure to stroke volume to generate arterial elastance (Ea). These were combined to assess cardiovascular performance (ventricular-arterial [VA] coupling ratio [Ea/Ees]). Eleven patients demonstrated flow-limiting (FL) CAD (hyperemic Pd/Pa <0.80; ST-segment depression on exercise); five patients without flow-limiting (NFL) CAD served as the control group. Exercise in the presence of FL CAD was associated impairment of Ees, increased Ea, and deterioration of VA coupling. In the control cohort, exercise was associated with increased Ees and improved VA coupling. The backward compression wave energy directly correlated with the magnitude contraction as measured by dP/dTmax (r = 0.88, p = 0.004). This study demonstrates that in the presence of flow-limiting CAD, exercise to maximal effort can lead to impairment of LV contractile function and a deterioration in VA coupling compared to a control cohort.

[The preliminary value of vector flow mapping on assessment of left intraventricular pressure difference in patients with paroxysmal atrial fibrillation].

This study aims to explore the intraventricular pressure difference (IVPD) within left ventricle in patients with paroxysmal atrial fibrillation (PAF) by using the relative pressure imaging (RPI) of vector flow mapping (VFM). Twenty patients with paroxysmal atrial fibrillation (PAF) and thirty control subjects were enrolled in the study. Systolic and diastolic IVPD derived from VFM within left ventricle and conventional echocardiographic parameters were analyzed. It was found that the B-A IVPD of left ventricle in PAF patients showed the same pattern as controls-single peak and single valley during systole and double peaks and double valleys during diastole. Basal IVPD was the main component of base to apex IVPD (B-A IVPD). The isovolumetric systolic IVPD was associated with early systolic IVPD, early systolic IVPD was associated with late systolic IVPD, and late systolic IVPD was associated with isovolumic diastolic IVPD (all P < 0.05). The B-A IVPD and basal IVPD during isovolumetric systole, early systole, late systole and isovolumetric diastole in PAF patients significantly decreased (all P < 0.05). The study shows that the B-A IVPD pattern of the PAF group is the same as controls, but systolic B-A IVPD and basal IVPD are significantly reduced in PAF patients. VFM-derived RPI can evaluate left ventricular IVPD in PAF patients, providing a visually quantitative method for evaluating left ventricular hemodynamic mechanics in the patients with PAF.

Novel Estimation of Left Ventricular Filling Pressure Using 3-D Speckle-Tracking Echocardiography: Assessment in a Decompensated Systolic Heart Failure Model.

E/e' allows for the non-invasive estimation of left ventricular (LV) filling pressure; however, Doppler malalignment can make the estimation unreliable, especially in dilated systolic failing hearts. The ratio of peak early diastolic filling rate to peak early diastolic global strain rate (FRe/SRe), which is a parameter derived from 3-D speckle-tracking echocardiography to estimate filling pressure, may be better applied in dilated systolic failing hearts because it can be obtained without the Doppler method. We investigated whether FRe/SRe could provide a better estimation of filling pressure than E/e' in 23 dogs with decompensated systolic heart failure induced by microembolization. FRe/SRe had better correlation coefficients with LV end-diastolic pressure (0.75-0.90) than did E/e' (0.40). The diagnostic accuracy of FRe/SRe in distinguishing elevated filling pressure was significantly higher than that of E/e'. This study indicates that FRe/SRe may provide a better estimation of LV filling pressure than E/e' in dilated systolic failing hearts.

Echocardiographic assessment of left ventricular filling pressure in patients with acute ST elevation myocardial infarction: an invasive validation study.

Backgrounds Assessment of left ventricular filling pressure (LVFP) is of clinical importance in patients with ST elevation myocardial infarction (STEMI). Although several echocardiographic parameters are recommended for the assessment of LVFP, validation of these parameters in patients with STEMI is missing. We aimed to investigate the clinical utility of these parameters in acute settings. Methods: We prospectively included consecutive patients with STEMI. LV end-diastolic pressure (LVEDP) was measured following primary PCI and echocardiographic examination was performed within 24 hours. Mean left atrial pressure (mLAP) was calculated both invasively using Yamamoto's formula and non-invasively using Naugeh's formula. Mean LAP was considered increased when exceeded 18 mmHg. Results: Patients were grouped according to LVEDP, group 1(41 patients) and group 2(114 patients).There was no significant difference between groups in terms of comorbidities. NT pro-BNP levels (p < 0.001) and peak level of Hs-TnT (p-value: 0.002) were significantly higher in group 2. Average E/e' ratio was significantly higher in group 2 (10.19 ± 3.15 vs. 12.04 ± 4.83, p: 0.046). Isovolumetric relaxation time was longer in group 2 (p < 0.001) and left atrial volume index (LAVI) was also significantly higher in group 2 (p < 0.001). Regression analyses revealed that septal, lateral and average E/e' ratio, tricuspid regurgitation velocity, LAVI and left ventricular volume are correlated with mLAP. Among group 2 patients only 14 Patients fulfilled the increased LVFP criteria suggested by current guidelines. Conclusions Echocardiographic parameters indicating increased LVFP require validation and may need to be modified in patients with STEMI. Moreover, current algorithms underestimate the actual number of patients with increased LVFP.

An exploratory assessment of stretch-induced transmural myocardial fiber kinematics in right ventricular pressure overload.

Right ventricular (RV) remodeling and longitudinal fiber reorientation in the setting of pulmonary hypertension (PH) affects ventricular structure and function, eventually leading to RV failure. Characterizing the kinematics of myocardial fibers helps better understanding the underlying mechanisms of fiber realignment in PH. In the current work, high-frequency ultrasound imaging and structurally-informed finite element (FE) models were employed for an exploratory evaluation of the stretch-induced kinematics of RV fibers. Image-based experimental evaluation of fiber kinematics in porcine myocardium revealed the capability of affine assumptions to effectively approximate myofiber realignment in the RV free wall. The developed imaging framework provides a noninvasive modality to quantify transmural RV myofiber kinematics in large animal models. FE modeling results demonstrated that chronic pressure overload, but not solely an acute rise in pressures, results in kinematic shift of RV fibers towards the longitudinal direction. Additionally, FE simulations suggest a potential protective role for concentric hypertrophy (increased wall thickness) against fiber reorientation, while eccentric hypertrophy (RV dilation) resulted in longitudinal fiber realignment. Our study improves the current understanding of the role of different remodeling events involved in transmural myofiber reorientation in PH. Future experimentations are warranted to test the model-generated hypotheses.

Combined Assessment of Functional and Metabolic Performance of Human Donor Hearts: Possible Application in Donation After Circulatory Death.

BACKGROUND: Donation after circulatory death (DCD) represents an increasing source of organs. However, evaluating the suitability of DCD hearts for transplantation represents a challenge. Contractile function is the ultimate determinant of recovery. We developed a novel technique in an ex vivo rig for the measurement of contractility using intraventricular balloons. We compared this technique with the measurement of lactate metabolism, the current gold standard. METHODS: Human DCD (n = 6) and donation after brain death (n = 6) hearts were preserved by perfusion with a cold oxygenated crystalloid solution for 4 h, transferred to a blood perfusion rig at 37 °C where balloons were inserted into the left (LV) and right (RV) ventricles to measure developed pressure (DP = systolic minus diastolic). Perfusate lactate levels were measured for metabolic assessment. Concordance between LVDP and lactate was assessed during 4 h using cutoffs for LVDP of 70 mm Hg and for lactate of 10 mmol/L. RESULTS: Measurements of contractile function (LVDP) and metabolism (lactate levels) were deemed concordant in 7 hearts with either a high LVDP (mean 100 mm Hg) with low lactate (mean 6.7 mmol/L)) or a low LVDP (15 mm Hg) with high lactate (mean 17.3 mmol/). In the remaining 5 hearts, measurements were deemed discordant: 4 hearts had high LVDP (mean 124 mm Hg), despite high lactate levels 17.3 mmol/L) and 1 had low LVDP (54 mm Hg) but low lactate (6.9 mmol/L). CONCLUSIONS: The intraventricular balloon technique provides useful information regarding contractile recovery of donor hearts that if combined with lactate metabolism has potential application for the evaluation of DCD and marginal donation after brain death hearts before transplant.

Usefulness of the Right Parasternal Echocardiographic View to Improve the Hemodynamic Assessment After Valve Replacement for Aortic Stenosis.

Right-parasternal-view (RPV) often provides the best hemodynamic assessment of the aortic-valve-stenosis by echocardiography. However, no detailed study on patients with aortic prosthesis is available. Thus, RPV usefulness is left as an anecdotical notion in this context. We aimed to define feasibility and clinical-impact of RPV before and soon-after percutaneous implantation (TAVI) or surgical (SAVR) aortic-valve-replacement (AVR) for AS. Patients with severe-AS electively referred for AVR between September-2019 and February-2020 were prospectively evaluated. Echocardiographic examinations inclusive of apical and RPV to measure aortic-peak-velocity , gradients and area (AVA) were performed the day before AVR and at hospital discharge and compared by matched-pair-analysis. Forty-seven patients (mean age 79 ± 8 years, 63% female, ejection-fraction 61 ± 6%) referred for SAVR (24 [51%]) or TAVI (23 [49%]) were enrolled. RPV was feasible in 45 patients (96%) before-AVR but in only 32 after-AVR (68%), particularly after SAVR (50%) than TAVI (87% p = 0.005). RPV remained the best acoustic window after TAVI in 75% of cases. Hemodynamic assessment of TAVI, but not SAVR, invariably benefit from RPV versus apical evaluation (aortic-peak-velocity: 2.57 ± 0.39 vs 2.23 ± 0.47 m/sec, p = 0.002; mean gradient: 15 ± 5 vs 12 ± 5 mm Hg, p = 0.01). Five (11%) patients presented severe patient-prosthesis-mismatch, 4 of which were detectable only by RPV. This pilot-experience demonstrates that RPV feasibility is slightly reduced after AVR. RPV can improve the hemodynamic assessment of the prosthetic valve versus apical view, including the detection of patient-prosthesis-mismatch. Furthermore, when RPV is the best acoustic windows in patients with severe AS, it generally remains so after-TAVI.

Noninvasive assessment of intraventricular pressure difference in left ventricular dyssynchrony using vector flow mapping.

Diastolic intraventricular pressure difference (IVPD) reflects left ventricular (LV) diastolic function. The relative pressure imaging (RPI) enables the noninvasive quantification of IVPD based on vector flow mapping (VFM) and visualization of regional pressure distribution. LV dyssynchrony causes deterioration of cardiac performance. However, it remains unclear how IVPD is modulated by LV dyssynchrony. LV dyssynchrony was created in ten open-chest dogs by right ventricular (RV) pacing. The other ten dogs undergoing right atrial (RA) pacing set at the similar heart rate with RV pacing were used as controls. Echocardiographic images were acquired at baseline and during pacing simultaneously with LV pressure measurement by a micromanometer. Pressure difference (ΔP) was computed between the apex and the base of the LV inflow tract during a cardiac cycle by RPI and ΔP during isovolumic relaxation time (ΔPIRT), a parameter of diastolic suction, and that during early filling phase (ΔPE) were measured. During RV pacing, stroke volume (SV) and ΔPIRT decreased significantly, while ΔPE did not change compared to the baseline. During RA pacing, SV, ΔPIRT and ΔPE did not change significantly. ΔPIRT tended to correlate with -dP/dtmin and end-systolic volume, and significantly correlated with ejection fraction. IVPD during isovolumic relaxation time was decreased by LV dyssynchrony, while IVPD during early filling phase was not. A reduction of diastolic suction is observed in LV dyssynchrony and is significantly related to a decrease in SV.

Effect of left ventricular assist device implantation on right ventricular function: Assessment based on right ventricular pressure-volume curves.

Right ventricular (RV) failure is significantly associated with morbidity and mortality after left ventricular assist device (LVAD) implantation. However, it remains unclear whether LVAD implantation could worsen RV function. Therefore, we aimed to investigate the effect of LVAD implantation on RV function by comparing RV energetics derived from the RV pressure-volume curve between before and after LVAD implantation. This exploratory observational study was performed between September 2016 and January 2018 at a national center in Japan. Twenty-two patients who underwent LVAD implantation were included in the analysis. We measured RV energetics parameters: RV stroke work index (RVSWI), which was calculated by integrating the area within the RV pressure-volume curve; RV minute work index (RVMWI), which was calculated as RVSWI × heart rate; and right ventriculo-arterial coupling, which was estimated as RV stroke volume/RV end-systolic volume. We compared RV energetics between before and after LVAD implantation. Although RVSWI was similar [424.4 mm Hg · mL/m2 (269.5-510.3) vs. 379.9 mm Hg · mL/m2 (313.1-608.8), P = 0.485], RVMWI was significantly higher after LVAD implantation [29 834.1 mm Hg · mL/m2 /min (18 272.2-36 357.1) vs. 38 544.8 mm Hg · mL/m2 /min (29 016.0-57 282.8), P = 0.001], corresponding to a significantly higher cardiac index [2.0 L/min/m2 (1.4-2.2) vs. 3.7 L/min/m2 (3.3-4.1), P < 0.001] to match LVAD flow. Right ventriculo-arterial coupling was significantly higher after LVAD implantation [0.360 (0.224-0.506) vs. 0.480 (0.343-0.669), P = 0.025], suggesting that the efficiency of RV performance improved. In conclusion, higher RVMWI with higher cardiac index to match LVAD flow and improved efficiency of RV performance indicate that LVAD implantation might not worsen RV function.

Value of Echocardiographic Right Ventricular and Pulmonary Pressure Assessment in Predicting Transcatheter Tricuspid Repair Outcome.

OBJECTIVES: The aim of this study was to assess the value of echocardiographic right ventricular (RV) and systolic pulmonary artery pressure (sPAP) assessment in predicting transcatheter tricuspid edge-to-edge valve repair (TTVR) outcome. BACKGROUND: RV dysfunction and pulmonary hypertension are associated with poor prognosis and are systematically sought during tricuspid regurgitation evaluation. The value of echocardiographic assessment in predicting TTVR outcome is unknown. METHODS: Data were taken from the TriValve (Transcatheter Tricuspid Valve Therapies) registry, which includes patients undergoing TTVR at 14 European and North American centers. The primary outcome was 1-year survival free from hospitalization for heart failure, and secondary outcomes were 1-year survival and absence of hospital admission for heart failure at 1 year. RESULTS: Overall, 249 patients underwent TTVR between June 2015 and 2018 (mean tricuspid annular plane systolic excursion [TAPSE] 15.8 ± 15.3 mm, mean sPAP 43.6 ± 16.0 mm Hg). Tricuspid regurgitation grade ≥3+ was found in 96.8% of patients at baseline and 29.4% at final follow-up; 95.6% were in New York Heart Association functional class III or IV initially, compared with 34.3% at follow-up (p < 0.05). Final New York Heart Association functional class did not differ among TAPSE and sPAP quartiles, even when both low TAPSE and high sPAP were present. Rates of 1-year survival and survival free from hospitalization for heart failure were 83.9% and 78.7%, respectively, without significant differences according to baseline echocardiographic RV characteristics (TAPSE, fractional area change, and end-diastolic area) and sPAP (p > 0.05 for all). CONCLUSIONS: TTVR provides clinical improvement, with 1-year survival free from hospital readmission >75% in patients with severe tricuspid regurgitation. Conventional echocardiographic parameters used to assess RV function and sPAP did not predict clinical outcome after TTVR.

Effect of kidney transplantation on right ventricular function, assessment by 2- dimensional speckle tracking echocardiography.

BACKGROUND: Advanced chronic kidney disease often results in adverse cardiovascular outcomes and is the leading cause of mortality in patients with end stage renal diseases (ESRD). There is much information about the effect of chronic kidney diseases (CKD) on the left ventricle (LV) chamber, but the right ventricle (RV) as a neglected chamber had not been evaluated precisely, in spite of its importance. OBJECTIVES: The aim of this study was to evaluate the impact of successful kidney transplants on the RV systolic and diastolic function using the advanced method of 2D speckle tracking echocardiography and comparison with the conventional methods. METHOD: The study included 48 patients with CKD who were eligible for kidney transplantation and underwent successful kidney transplantations. Right ventricular indices were evaluated, while RV function was focused by conventional methods and 2D speckle tracking echocardiography before the successful kidney transplant and 1 week, 1 month, and 3 months after the successful kidney transplant. RESULTS: The results of the study showed that RV global longitudinal strain and RV free wall longitudinal strain improved over the time (P = 0.024, P < 0.001 respectively). It also represented that kidney transplantation did not have significant effect on the RV mid cavity diameter, tissue velocity, Myocardial performance index, RV longitudinal diameter, and Tricuspid annular plane systolic excursion indices, but for other indices this effect was significant. On the differences between the mean slope of regression line of the GLS variable in hypertensive subjects (1.0 ± 0.2) and non-hypertensive subjects (0.36 ± 0.32), an independent t-test showed that between the two groups in terms of the improvement of RVGLS, there was a significant statistical difference (P = 0.0067). CONCLUSION: Most of the ESRD patients had subtle RV dysfunction which could be better detected by recent echocardiography methods than conventional methods. Moreover, kidney transplantation led to considerable improvements in RV function in this population.

Model-based estimation of left ventricular pressure and myocardial work in aortic stenosis.

This paper proposes a model-based estimation of left ventricular (LV) pressure for the evaluation of constructive and wasted myocardial work of patients with aortic stenosis (AS). A model of the cardiovascular system is proposed, including descriptions of i) cardiac electrical activity, ii) elastance-based cardiac cavities, iii) systemic and pulmonary circulations and iv) heart valves. After a sensitivity analysis of model parameters, an identification strategy was implemented using a Monte-Carlo cross-validation approach. Parameter identification procedure consists in two steps for the estimation of LV pressures: step 1) from invasive, intraventricular measurements and step 2) from non-invasive data. The proposed approach was validated on data obtained from 12 patients with AS. The total relative errors between estimated and measured pressures were on average 11.9% and 12.27% and mean R2 were equal to 0.96 and 0.91, respectively for steps 1 and 2 of parameter identification strategy. Using LV pressures obtained from non-invasive measurements (step 2) and patient-specific simulations, Global Constructive (GCW), Wasted (GWW) myocardial Work and Global Work Efficiency (GWE) parameters were calculated. Correlations between measures and model-based estimations were 0.88, 0.80, 0.91 respectively for GCW, GWW and GWE. The main contributions concern the proposal of the parameter identification procedure, applied on an integrated cardiovascular model, able to reproduce LV pressure specifically to each AS patient, by non-invasive procedures, as well as a new method for the non-invasive estimation of constructive, wasted myocardial work and work efficiency in AS.