Regional Right Ventricular Research Articles

P1771Right ventricular mechanical changes after septal myectomy for obstructive hypertrophic cardiomyopathy. Vector velocity imaging study

Abstract Objectives The impairment of right ventricular (RV) myocardial mechanics is evident in hypertrophic cardiomyopathy (HCM). It is independently influenced by LV mechanics and correlated to the severity of LV phenotype. We investigated the changes in RV global and regional deformation following surgical septal myectomy using vector velocity imaging (VVI). Methods 25 HCM patients, 68% males with mean age (34.5±12 years) were examined before and within two months after surgical myectomy using VVI. In addition to conventional echocardiographic parameters, peak systolic strain (εsys), strain rate (SR) and time to peak εsys (TTP) of regional RV free wall (RVFW) & septal walls were analyzed in longitudinal (long) directions from apical four chamber view and their (Δ)changes were calculated. Similar parameters were quantified in LV from apical 2 & 4 CH views. Intra-V-delay was defined as SD of TTP and inter-V dyssynchrony was estimated from TTP difference between the most delayed LV segment & RVFW. Results All study patients showed improvement of their functional class from NYHA class III to class I and reduction of LVOT gradient to below 20 mmHg except one patient who had 30 mmHg gradients at rest. There was significant reduction of septal thickness, left atrial diameter& volume, LVOT gradient, LVMI, severity of mitral regurgitation, tricuspid annular velocities (P<0.0001), RV diameter (P<0.02) and increase in LV internal dimensions (P<0.001) post myectomy. However, there was significant reduction of RV and LV systolic mechanics; RV global εsys % (from −16.1±4.4 to −12.9±2.9, P<0.0001) and LV global εsys %: from −11.6±2.8 to −9.4±2.2%, P<0.0001) respectively. The magnitude of reduction of RV strain (Δ RV εsys%, Δ SRsys) was directly correlated LV maximal wall thickness (r=0.46, P<0.01) and ΔRV dyssynchrony (TTP-SD), (r=0.4, P<0.05) and negatively correlated to age (r=−0.46, P<0.02), pre-op RV SRsys (r=−0.52, P<0.01) and pre-op LV EF% (r=−0.43, P<0.03). Meanwhile the reduction in RV diastolic mechanics: Δ RV SRe & SRa were directly correlated to PAP and LVOT gradient before surgery (r=0.62, P<0.002). Conclusion Despite improvement of patient functional status and reduction LVOT gradient, RV mechanics shows further deterioration after surgical myectomy. The magnitude of reduction is modestly related to cardiac phenotype and pre-op mechanical function.

Impact of Right Ventricular Geometry and Left Ventricular Hypertrophy on Right Ventricular Mechanics and Clinical Outcomes in Hypoplastic Left Heart Syndrome

Right ventricular (RV) function is a major determinant of survival in hypoplastic left heart syndrome (HLHS). However, the relation of RV geometry to myocardial mechanics and their relation to transplant-free survival are incompletely characterized. We retrospectively studied 48 HLHS patients from the Hospital for Sick Children, Toronto, (median age, 2.2; interquartile range, 3.62years) at different surgical stages. Patients were grouped by the presence (n=23) or absence (n=25) of RV "apical bulging" defined as a sigmoid-shaped septum with the RV leftward apical segment contiguous with the left ventricular (LV) lateral wall. Regional and global RV strain were measured using speckle-tracking echocardiography, and regional strains were analyzed for patterns and peak values. These were compared between HLHS anatomical subtypes and between patients with versus without apical bulging. We further investigated the association between RV geometry and dysfunction with the outcomes of heart failure, death, or transplant. RV global (-7.3%±2.8% vs -11.2%±4.4%; P=.001), basal septal (-3.8%±3.2% vs -11.4%±5.8%; P=.0001) and apicolateral (-5.1%±3.5% vs -8.0%±5.8%, P=.001) longitudinal strain were lower in patients with versus without apical bulging, respectively. Apical bulging was equally prevalent in all HLHS anatomical variants. Twenty of 22 (91%) patients with apical bulging displayed hypertrophy of the LV apical and lateral segments. Death or transplantation were approximately equal in both groups but related to reduced RV global strain in patients with (seven of seven) and not in those without apical bulging (two of eight; P=.022). These results suggest that the finding of apical bulging is related to the presence of a hypertrophied hypoplastic LV, with a negative impact on regional and global RV function. Therefore, analysis of RV and LV geometry and mechanics may aid in the assessment and prognostication of this high-risk population.

EFFECT OF PULMONARY HYPERTENSION SECONDARY TO CONGENITAL HEART DISEASE ON RIGHT VENTRICULAR VOLUMES AND FUNCTION: A COMPARATIVE STUDY BETWEEN TWO DIMENSIONAL, THREE DIMENSIONAL ECHOCARDIOGRAMS AND INVASIVE RV QUANTIFICATION

Background: Quantitative echo cardiographic assessment of right ventricular (RV) function is becoming of increasing interest in cardiac diseases that affect the right ventricle, such as congenital heart disease and acute or chronic pulmonary hypertension (PH),but is still challenging due to RV complex anatomy and structure. Aim of the Work: To study the effect of PH on the RV volumes and function using 2DE, 3DE and RV quantification by angiography in patients with PH secondary to congenital heart disease and to compare between 3D RV quantification by echocardiogram and invasive byangiography in patients with PH secondary to congenital heart disease. Patients and Methods: This cross sectional study included all patients with congenital heart diseases complicated by pulmonary hypertension referred to cardiology department in Ain shams university hospital for elective hemodynamic assessment. Results: The diagnostic accuracy of 3D RV and angiography (Ang.) RV parameters for detecting hemodynamic signs of pulmonary hypertension (a composite of PVR > 7) was shown by receiv‐er operating characteristic curves. The parameters with the largest areas under thecurve (AUC) were: 3D tenting volume (1.000) had the highest area under the curve followed by mean PAP and PASP, followed by 3D ‐ TV annulus area, Ang. RV EF,3D RV EF And lastly FAC. The best cut-off values of: 3D TV tenting volume >4.8 (Se: 100%, Sp: 100%), PASP >80(Se: 100%, Sp: 97.5%), mean PAP >50 (SE:100, SP: 97.5%), 3D TV annulus area >9.3 (SE: 100%, SP: 92.5), Ang. RV EF < =36% (SE=100%, SP= 80%), 3D RV EF <=42% (SE=100%, SP+77.5%)and RV FAC<=36 % (Se:100%, Sp: 67.5%). Conclusion: In PH patients, the quantitative assessment of globaland regional RV function by 3D provided a useful hemodynamic and prognostic information. Several indices can be obtained by 3D echocardiography non-invasively, to predict the PVR in congenital heart disease with PH.

Regional Versus Global Measurements of Right Ventricular Strain Performed in the Operating Room With Transesophageal Echocardiography

To compare regional and global measures of right ventricular (RV) strain in patients undergoing intraoperative transesophageal echocardiography (TEE). Prospective, nonrandomized, observational study. Single tertiary-level, university hospital. The study comprised 48 patients undergoing intraoperative TEE. None. A global RV strain measurement (termed RV 5-wall strain [RV 5WS]) was calculated by averaging the longitudinal strain calculated from multiple TEE views. This global strain measurement was compared with the more standard regional strain measurements obtained in a single 4-chamber view (RV free-wall strain [RV FWS] and RV global longitudinal strain [RV GLS]) and with traditional measures of RV function. Regional and global strain measurements were feasible in the operating room. RV FWS and RV GLS strongly correlated with RV 5WS (r = 0.86 and 0.87, respectively) with no significant bias and limits of agreement of approximately -5% to 5%. RV FWS and RV GLS were even more closely correlated with each other (r = 0.99) with no significant bias and limits of agreement less than -2% to 2%. Both regional and global RV strain measurements showed a high sensitivity (RV FWS 94%; RV GLS 94%; RV 5WS 89%) and moderate specificity (RV FWS 70%; RV GLS 67%; RV 5WS 63%) for RV dysfunction based on a reference standard of 3-dimensional RV ejection fraction. Both regional and global RV strain measurements are feasible in the operating room with TEE. Regional and global measures of RV function correlate well and are sensitive indicators of RV dysfunction.

Assessment of right ventricular function and relation to mortality after acute pulmonary embolism: A speckle tracking echocardiography-based study.

Right ventricular (RV) dysfunction is a common condition that is related to increased adverse outcomes in patients with acute pulmonary embolism (APE). Our aim was to assess timing and magnitude of regional RV function using speckle tracking echocardiography (STE) and to evaluate their relationship to long-term mortality in patients after APE. In total, 147 patients were enrolled at the onset of an APE episode and followed for 12±1.1months. For all patients, the clinical, laboratory, and echocardiography examinations were performed at the diagnosis of APE and at the end of the 1-year follow-up. Of the 147 patients, 44 (29.9%) died during the 1-year follow-up after APE. The patients who died had lower RV free wall peak longitudinal systolic strains (PLSS) and left ventricular (LV) PLSS and higher RV peak systolic strain dispersion (PSSD) index which means the electromechanical dispersion when compared with the survivors. The difference in time to PLSS between the RV free wall and LV lateral wall (RVF-LVL) which means the electromechanical delay was longer in patients who died than in those who survived during follow-up, and this difference was an independent predictor of mortality at 1year of follow-up after APE, with 86.4% sensitivity and 81.7% specificity. At the end of 1-year follow-up, the RV free wall PLSS and the LV global PLSS increased, whereas the RV PSSD index and the difference in time to PLSS between the RVF and LVL decreased. Acute pulmonary embolism was associated with RV dysfunction and RV electromechanical delay and dispersion. These parameters improved at the end of 1-year follow-up. The electromechanical delay index might be a useful predictor of mortality in patients after APE.

Echocardiographic predictors of intraoperative right ventricular dysfunction: a 2D and speckle tracking echocardiography study

BackgroundIntraoperative or post procedure right ventricular (RV) dysfunction confers a poor prognosis in the post-operative period. Conventional predictors for RV function are limited due the effect of cardiac surgery on traditional RV indices; novel echocardiographic techniques hold the promise to improve RV functional stratification.MethodsComprehensive echocardiographic data were collected prospectively during elective cardiac surgery. Tricuspid annular plane systolic excursion (TAPSE), peak RV systolic velocity (S′), and RV fractional area change (FAC) were quantified on transesophageal echo (TEE). RV global and regional (septal and free wall) longitudinal strain was quantified using speckle-tracking echo in RV-focused views. Two intraoperative time points were used for comparison: pre-sternotomy (baseline) and after chest closure.ResultsThe population was comprised of 53 patients undergoing cardiac surgery [15.1% coronary artery bypass graft (CABG) only, 28.3% valve only, 50.9% combination (e.g. valve/CABG, valve/aortic graft) surgeries], among whom 38% had impaired RV function at baseline defined as RV FAC < 35%. All conventional RV functional indices including TAPSE, S′ and FAC declined immediately following CPB (1.5 ± 0.3 vs.1.1 ± 0.3 cm, 8.0 ± 2.1 vs. 6.2 ± 2.5 cm/s, 36.8 ± 9.3 vs. 29.3 ± 10.6%; p < 0.001 for all). However, left ventricular (LV) and RV hemodynamic parameters remained unchanged (LV ejection fraction (EF): 56.8 ± 13.0 vs. 55.8 ± 12.9%; p = 0.40, pulmonary artery systolic pressure (PASP): 26.5 ± 7.4 vs 27.3 ± 6.7 mmHg; p = 0.13). Speckle tracking echocardiographic data demonstrated a significant decline in RV global longitudinal strain (GLS) [19.0 ± 6.5 vs. 13.5 ± 6.9%, p < 0.001]. Pre-procedure FAC, GLS and free wall strain predicted RV dysfunction at chest closure (34.7 ± 9.1 vs. 41.6 ± 8.1%, p = 0.01, 17.7 ± 6.5 vs. 21.8 ± 5.4%; p = 0.03, 20.3 ± 6.4 vs. 24.2 ± 5.8%; p = 0.04), whereas traditional linear RV indices such as TAPSE and RV S′ at baseline had no impact on intraoperative RV dysfunction (p = NS for both).ConclusionsGlobal and regional RV function, as measured by 2D indices and strain, acutely decline intraoperatively. Impaired RV strain is associated with intraoperative RV functional decline and provides incremental value to traditional RV indices in predicting those who will develop RV dysfunction.

Right and left ventricular interaction in pulmonary hypertension: Insight from velocity vector imaging.

To evaluate whether global peak systolic strain (PSS) and peak systolic strain rate (PSSR) derived from velocity vector imaging (VVI) allow early recognition of regional and global right ventricular (RV) dysfunction and the impact of this on left ventricular (LV) function in patients with pulmonary hypertension (PHT). RV function is an important determinant of prognosis in patients with heart failure, pulmonary hypertension, heart transplant, and congenital heart diseases. However, evaluation of the right ventricle is often limited by its complex geometry and inadequate visualization of RV free wall. Furthermore, the impact of RV dysfunction on the LV function is not well elucidated. Ninety-nine participants, 35 control patients with normal RV systolic pressure (RVSP) (<30mm Hg) and 64 patients with PHT (25 with mild-to-moderate increase in RVSP [≥36 and <60mm Hg] and 39 with severe increase in RVSP [≥60mm Hg]), underwent comprehensive echo-Doppler assessment and velocity vector imaging (VVI) for strain rate analysis. RV regional peak systolic and diastolic tangential velocity, strain, and strain rate were obtained from the basal, mid and apical segments of the RV free wall and interventricular septum (IVS) from apical 4-chamber view at end-expiration. Similar data were obtained from eighteen LV segments from apical 4-chamber, 2-chamber, and long-axis views. Peak systolic strain, strain rate, and tangential velocity at all segments in the RV free wall and IVS were decreased compared to controls in patients with PHT (P<0.001). Significant correlation (r>0.60; P<0.001) was noted between RVSP and systolic and diastolic strain and strain rate at basal segment in IVS and global RV function. Peak early diastolic strain rate at all segments was also decreased in PHT patients compared with control patients (P<0.01). Furthermore, RV systolic and diastolic strain and strain rate were lower in group 2 with mild-to-moderate hypertension while the conventional echo parameters were normal. Except for IVS segments, other LV segments had no statistical differences in systolic and diastolic velocity, strain, and strain rate compared to controls. However, they were lower than the published normal range. Strain and strain rate derived from VVI demonstrates early recognition of systolic and diastolic RV dysfunction in patients with PHT compared to controls. PHT is associated with global and regional RV systolic and diastolic dysfunction. Systolic and diastolic strain and strain rate from LV was lower compared to controls but were not statistically significant. This may indicate subclinical LV dysfunction in these patients, suggesting that conventional LV function parameters may not be sensitive to recognize subclinical LV dysfunction.

Myocardial strain abnormalities in fetuses with pulmonary atresia and intact ventricular septum.

Global and regional myocardial deformation have not been well described in fetuses with pulmonary atresia and intact ventricular septum (PA/IVS). Speckle-tracking echocardiography (STE), an angle-independent technique for assessing global and regional strain, may be a more sensitive way of determining ventricular systolic dysfunction compared with traditional 2D echocardiography. The aim of this study was to assess myocardial deformation in fetuses with PA/IVS compared with control fetuses and to determine if, in fetuses with PA/IVS, strain differs between those with and those without right ventricle-dependent coronary circulation (RVDCC). This was a retrospective analysis of fetuses with PA/IVS examined at two medical centers between June 2005 and October 2017. Left ventricular (LV) and right ventricular (RV) regional and global longitudinal strain (GLS) and strain rate were obtained using STE, and comparisons were made between fetuses with PA/IVS and gestational age (GA)-matched controls. Postnatal outcome was assessed, including the presence of RVDCC. Fifty-seven fetuses with PA/IVS and 57 controls were analyzed at a mean GA of 26.5 ± 5 weeks. LV-GLS was significantly decreased in fetuses with PA/IVS compared with controls (-17.4 ± 1.7% vs -23.7 ± 2.0%, P < 0.001). LV strain rate was also significantly decreased (-1.01 ± 0.21/s vs -1.42 ± 0.20/s, P < 0.001). Fetuses with PA/IVS had decreased strain in all segments. Similarly, RV strain was significantly decreased in fetuses with PA/IVS (-11.6 ± 3.8% vs -24.6 ± 2.5%, P < 0.0001). Thirty-six patients had postnatal cardiac catheterization performed to define coronary anatomy; 10 fetuses had RVDCC. Fetuses with RVDCC had decreased LV strain compared with those without (-15.8 ± 1.2% vs -17.9 ± 1.7%, P = 0.009). RV strain was also decreased in fetuses with RVDCC vs those without (-7.0 ± 2.9% vs -12.1 ± 3.2%, P = 0.0004). Fetuses with PA/IVS have decreased global and regional LV and RV strain compared with controls. The finding of decreased LV strain may be due to altered ventricular mechanics in the context of a hypertensive right ventricle and/or abnormal coronary perfusion. Moreover, fetuses that were found to have RVDCC postnatally had decreased LV and RV strain compared with those that did not. These results encourage further investigation to assess whether fetal ventricular strain could be a prenatal predictor of RVDCC. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Impact of tricuspid annular size reduction on right ventricular function, geometry and strain.

Restrictive tricuspid annuloplasty is a clinically accepted approach to treat functional tricuspid regurgitation. We set out to investigate the effect of varying degrees of tricuspid annular reduction on the right ventricular (RV) function, geometry and strain. Eight, healthy sheep (45 ± 4 kg) had 6 sonomicrometry crystals implanted around the tricuspid annulus and 20 onto the epicardium of the right ventricle defining 3 free wall regions: basal, mid and lower. A polypropylene annuloplasty suture was placed around the tricuspid annulus and externalized to an epicardial tourniquet. Simultaneous echocardiographic, haemodynamic and sonomicrometry data were acquired at baseline and during 5 consecutive annular reduction steps (TAR 1-5) with successive (5-7 mm) suture cinching. RV free wall circumferential, longitudinal and areal cardiac and interventional strains, RV radius of curvature (ROC), cross-sectional area and tricuspid annular dimensions were calculated from 3-dimensional crystal coordinates. TAR 1-5 resulted in 19 ± 15%, 35 ± 15%, 51 ± 15%, 60 ± 15% and 68 ± 13% tricuspid annular area reduction, respectively. TAR 1 and 2 had minimal influence on the RV function, RV-ROC and strains. TAR 4 and 5 decreased RV-ROC in basal and mid-regions, but reduced the RV cross-sectional area change (from 19 ± 4% at baseline to 14 ± 3% and 13 ± 2%, respectively, P < 0.001) and circumferential and areal strains. TAR 3 significantly decreased free wall RV-ROC from 44.0 ± 1.5 to 42.6 ± 2.4 mm P < 0.001 at the RV base but maintained the regional ventricular function and strains. In healthy ovine hearts, a tricuspid annular area reduction of ∼50% provides optimal conditions for reducing RV-ROC while maintaining regional RV function and strain patterns.

Analysis of Regional Right Ventricular Function by Tissue Doppler Imaging in Patients with Aortic Stenosis.

Background:Right ventricular (RV) dysfunction is frequently observed in patients with aortic stenosis (AS). Nevertheless, assessment of regional RV deformation is yet not performed. The aim of the study was to analyze the impact of moderate and severe AS on global and regional RV function by a multisegmental approach using tissue Doppler imaging (TDI).Methods:In 50 patients (Group I – AS [n = 25] and Group II – normal controls [n = 25]), additional echocardiographic views of the RV were prospectively performed. The TDI sample volume was placed in the basal myocardial region of the anterior (RV-anterior), inferior (RV-inferior), and free RV wall (RV-free wall) to assess the following parameters: S'RV, E'RV, and A'RV waves; IVCTRV; IVRTRV; and myocardial performance index (MPIRV).Results:In AS patients, left ventricular (LV) mass index, left atrial (LA) volume index, and LV end-diastolic pressure were significantly increased. Moreover, AS patients had higher systolic pulmonary artery pressure (sPAP) and lower values for PV AccT (P < 0.0001), but TAPSE was not different between the two groups (P = 0.062). In AS patients, IVRTRV-anterior, IVRTRV-inferior, and IVRTRV-free wall and MPIRV were statistically increased (P < 0.0001). A significant correlation between IVRTRV (evaluated at all three regions) and the parameters including sPAP, PV AccT, and ELV/e'LV ratio was observed in AS. A strong correlation was observed between IVRTRV-free wall/inferior and AS severity by evaluation of velocities, gradient, and aortic valve area (P < 0.0001).Conclusions:The present study reports a correlation between the severity of AS and the increase of IVRTRV and MPIRV. Thus, a distinct analysis of RV performance is important for echocardiographic evaluation of patients with AS.

Timing and magnitude of regional right ventricular function and their relationship with early hospital mortality in patients with acute pulmonary embolism.

Objective:Right ventricular (RV) dysfunction in acute pulmonary embolism (APE) has been associated with increased mortality and morbidity. The aim of the present study was to assess the timing and magnitude of regional RV functions using speckle-tracking echocardiography (STE) and their relationship to early hospital mortality in patients with APE.Methods:One hundred forty-two patients were prospectively studied at the onset of an acute episode and after a median follow-up period of 30 days. Their clinical and laboratory characteristics were recorded. For all patients, conventional two-dimensional echocardiography and STE were performed within 24 h after the diagnosis of APE.Results:Twenty-eight (19.7%) patients died during the hospitalization follow-up. Patients who died during hospitalization were older and had higher high sensitivity cardiac troponin T levels, and a higher percentage of patients had simplified Pulmonary Embolism Severity Indexes. In STE analyses, they had lower RV free wall peak longitudinal systolic strain (PLSS) and higher RV peak systolic strain dispersion indexes. The time to PLSS difference between RV free wall and LV lateral was longer in patients who died during hospitalization than in those who survived, and this was an independent predictor of early hospital mortality with 85.7% sensitivity and 75.0% specificity in patients with APE.Conclusion:APE was associated with RV electromechanical delay and dispersion. Electromechanical delay index might be useful to predict early hospital mortality in patients with APE.

Right Ventricular Mechanical Changes after Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy: Vector Velocity Imaging Study

Objectives: The impairment of right ventricular (RV) myocardial mechanics is evident in hypertrophic cardiomyopathy (HCM). It is independently influenced by LV mechanics and correlated to the severity of LV phenotype. We investigated the changes in RV global and regional deformation following surgical septal myectomy using vector velocity imaging (VVI). Methods: 25 HCM patients, 68% males with mean age (34.5 ± 12 years) were examined before and within two months after surgical myectomy using VVI. In addition to conventional echocardiographic parameters, peak systolic strain (esys), strain rate (SR) and time to peak esys (TTP) of regional RV free wall (RVFW) & septal walls were analyzed in longitudinal (long) directions from apical four-chamber view and their (Δ) changes were calculated. Similar parameters were quantified in LV from apical 2 & 4 CH views. Intra-V-delay was defined as SD of TTP and inter-V dyssynchrony was estimated from TTP difference between the most delayed LV segment & RVFW. Results: All study patients showed improvement of their functional class from NYHA class III to class I and reduction of LVOT gradient to below 20 mmHg except one patient who had 30 mmHg gradients at rest. There was significant reduction of septal thickness, left atrial diameter & volume, LVOT gradient, LVMI, severity of mitral regurgitation, tricuspid annular velocities (P < 0.0001), RV diameter (P < 0.02) and increase in LV internal dimensions(P < 0.001) post myectomy. However, there was significant reduction of RV and LV systolic mechanics; RV global esys % (from -16.1% ± 4.4% to -12.9% ± 2.9%, P < 0.0001) and LV global esys %: from -11.6% ± 2.8% to -9.4% ± 2.2%, P < 0.0001) respectively. The magnitude of reduction of RV strain (ΔRV esys %, ΔSRsys) was directly correlated LV maximal wall thickness (r = 0.46, P < 0.01) and ΔRV dyssynchrony (TTP-SD) (r = 0.4, P < 0.05) and negatively correlated to age (r = -0.46, P < 0.02), pre-op RV SRsys (r = -0.52, P < 0.01) and pre-op LV EF % (r = -0.43, P < 0.03). Meanwhile, the reduction in RV diastolic mechanics: ΔRV SRe & SRa were directly correlated to PAP and LVOT gradient before surgery (r = 0.62, P < 0.002). Conclusion: Despite the improvement of patient functional status and reduction LVOT gradient, RV mechanics shows further deterioration after surgical myectomy. The magnitude of reduction is modestly related to cardiac phenotype and pre-op mechanical function.

Incremental prognostic value of changes in 3D right ventricular function in pulmonary hypertension

Outcomes in pulmonary hypertension (PH) are related to right ventricular (RV) function and remodeling. We hypothesized that changes in RV function, especially area strain (AS), could provide incremental prognostic data. To assess global and regional 3D RV function changes between baseline and 6-months visit and evaluate their prognostic value in PH. In total, 65 PH patients were prospectively included in this longitudinal study. All patients underwent 2D and 3D transthoracic echocardiography at baseline and 6-month follow-up. 3D RV echocardiographic sequences were analyzed by semi-automatic software and output meshes were post-processed to extract regional deformation. At baseline, there was no significant difference in RV AS between patient subgroups. Patients who were considered clinically stable or improving presented at 6-months a significant increase in RV EF ( P = 0.04) and decrease in RV global AS ( P = 0.001) ( Fig. 1 ). The most significant regional changes occurred within the septum. Over a median follow-up of 24.8 months [22.1–25.7], 16 patients died from PH or were transplanted. On multivariate COX analysis, 6-month changes in WHO class (HR 17.4[5.2–58.5]), BNP (HR 1.003[1.001–1.004]) and RV global AS (HR 1.12[1.03–1.21]) were independent predictors of survival. Changes in WHO function class, BNP and 3D RV AS could help stratifying the PH patients’ risk. Our study demonstrates the additional prognostic value of following changes in RV deformation using 3D echocardiography.

DIAGNOSTIC YIELD OF CARDIOVASCULAR MAGNETIC RESONANCE (CMR) SCREENING FOR ARRHYTHMOGENIC RIGHT VENTRICULAR CARDIOMYOPATHY (ARVC) STRATIFIED BY BASELINE ECHOCARDIOGRAPHY FINDINGS OF THE RIGHT VENTRICLE

Arrythmogenic right ventricular cardiomyopathy (ARVC) is a rare inherited cardiomyopathy but an important cause of sudden death. Cardiovascular Magnetic Resonance (CMR) imaging is considered the gold-standard for exclusion of its structural phenotype, however, limited availability poses challenge in many communities. We aimed to study the relative diagnostic yield of CMR in patients with versus without abnormal right ventricular (RV) findings by routine 2D echocardiography. 447 patients referred for the screening of ARVC between February 2015 and December 2017 were identified from the Cardiovascular Imaging Registry of Calgary (CIROC). A standardized CMR imaging and analysis protocol was used to assess chamber volumes, function and architectural changes in accordance with the 2010 modified Task Force Criteria (mTFC). All patients having echocardiographic imaging within 12 months prior to CMR were identified and a blinded review of reports was performed. A final clinical diagnosis was derived based on the assimilation of all clinical information, and was classified as meeting or not meeting mTFC for ARVC. Of 447 enrolled patients, 387 (76.6%) had echocardiogram performed and were studied. A final diagnosis of definite ARVC was established in nine (2.3%) patients. Echocardiography reported no RV abnormalities in 283 (73.1%) patients (Group A), while 104 patients (26.9%) had at least one abnormal finding (Group B), defined as; reduced RV function, regional RV wall motion abnormality, global or focal dilatation, aneurysm or “hyper-reflective” trabeculations. In Group A, the yield of any mTFC by CMR was 4 (1.4%) with three patients having a minor and one having a major criterion. Two Group A patients (0.7%) ultimately received a diagnosis of ARVC, neither showing any imaging-based abnormalities. In Group B, the yield of any mTFC by CMR was 13 (12.5%) with nine subjects having a major and 4 having a minor criterion. Seven Group B patients (6.7%) were eventually diagnosed with ARVC, 5 (4.8%) meeting a CMR-based mTFC and 2 (1.9%) with normal CMR. Overall, the sensitivity and specificity of CMR for ARVC was 0% and 98.6% in Group A, and 71.4% and 91.7% in Group B. Among patients without RV abnormality by echocardiography referred to CMR for suspected ARVC, the yield of a CMR-based mTFC was low (1.4%) and did not lead to a diagnosis of ARVC in any subject. In contrast, patients with an RV abnormality had a CMR-based yield of 12.5%, leading to a diagnosis of ARVC in 4.8% of patients.

Three-dimensional analysis of regional right ventricular shape and function in repaired tetralogy of Fallot using cardiovascular magnetic resonance

BackgroundPatients with surgically repaired tetralogy of Fallot (rTOF) often have residual pulmonic valve regurgitation, leading to abnormal remodeling and dysfunction of the right ventricle often requiring pulmonic valve replacement. We tested the hypothesis that 3D analysis of right ventricular (RV) shape and function may reveal differences in regional adaptive remodeling that occurs in patients with rTOF, depending on whether a transannular patch (TAP) was utilized. MethodsForty patients with rTOF who underwent cardiac magnetic resonance imaging (1.5 T), including 20 with and 20 without TAP, and 10 normal controls were studied. Images were analyzed to measure RV endocardial curvature and global and regional volume and function. ResultsRV ejection fraction (EF) was 42 ± 11% in TAP and 38 ± 9% in no-TAP (p = 0.19), both lower than 54 ± 3% in controls (p < 0.01). Left ventricular (LV) EF was 54 ± 9% in TAP, 54 ± 8% in no-TAP (p = 0.87) and 61 ± 16% in controls (both p < 0.01). Indexed LV end-diastolic volumes were higher in no-TAP than in TAP subgroup (p = 0.02). With TAP, mid RV septum showed lower curvature during diastole (less convex), than the mid and apical free walls and free wall adjacent to the RV outflow tract (RVOT; more convex). There were no differences in curvature during systole between rTOF subgroups but mid and RVOT free walls showed higher curvature versus controls. ConclusionsThis is the first study to comprehensively describe the influence of TAP on changes in regional RV shape in patients with rTOF. Understanding these differences may help guide therapeutic options for residual pulmonary valve regurgitation in rTOF patients.

Association of regional epicardial right ventricular electrogram voltage amplitude and late gadolinium enhancement distribution on cardiac magnetic resonance in patients with arrhythmogenic right ventricular cardiomyopathy: Implications for ventricular tachycardia ablation

Criteria for identification of anatomic ventricular tachycardia substrates in arrhythmogenic right ventricular cardiomyopathy (ARVC) on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) are unclear. The purpose of this study was to define (1) the association of regional right ventricular (RV) epicardial voltage amplitude with the distribution of LGE; and (2) appropriate image signal intensity (SI) thresholds for ventricular tachycardia substrate identification in ARVC. Preprocedural LGE-CMR and epicardial electrogram mapping were performed in 10 ARVC patients. The locations of epicardial electrogram map points, obtained during sinus rhythm with intrinsic conduction or RV pacing, were retrospectively registered to the corresponding LGE image regions. Standardized SI z-scores (standard deviation distance from the mean) were calculated for each 10-mm region surrounding map points. In patient-clustered, generalized estimating equations models that included 3205 epicardial electroanatomic points and corresponding SI measures, bipolar (-1.43 mV/z-score; P <.001) and unipolar voltage amplitude (-1.22 mV/z-score; P <.001) were associated with regional SI z-scores. In contrast to the QRS-late potential (LP) interval (P = .362), the LP activation index, defined as electrogram duration divided by QRS-LP, was associated with regional SI z-scores (P <.001). SI z-score thresholds >0.05 (95% confidence interval -0.05 to 0.15) and <-0.16 (95% confidence interval -0.26 to 0.06) corresponded to bipolar voltage measures <0.5 and >1.0 mV, respectively. Increased RV gadolinium uptake is associated with lower epicardial bipolar and unipolar electrogram voltage amplitude. Standardized LGE-CMR SI z-scores may augment preprocedural planning for identification of low-voltage zones and abnormal myocardium in ARVC.

RIGHT VENTRICULAR MECHANICAL DISPERSION BY STRAIN ECHOCARDIOGRAPHY IMPACTS PROGNOSIS IN SIGNIFICANT TRICUSPID REGURGITATION

Chronic volume & pressure overload in tricuspid regurgitation (TR) leads to right ventricular (RV) myocardial fibrosis, RV dysfunction & worse outcome. RV mechanical dispersion (MD) by speckle-tracking echocardiography may detect regional RV functional abnormalities. We sought to assess the

Improved right ventricular index of myocardial performance in the assessment of right ventricular function after coronary artery bypass grafting.

Decreased right ventricular (RV) longitudinal function following coronary artery bypass grafting (CABG), as assessed by tricuspid annular systolic excursion (TAPSE) and RV peak systolic velocity (RVS') is a known condition. We aimed to explore the feasibility of the right ventricular index of myocardial performance (RIMP) in the assessment of RV function after CABG at rest and during peak dobutamine stress echocardiography (DSE). Forty-two patients indicated for CABG were included in this study. Coronary angiography, DSE and exercise bicycle test were performed within 6 weeks before and 3 months after CABG. The RIMP, RVS' and TAPSE at the lateral tricuspid annulus were also assessed. The results were presented as mean ± standard deviation. The RIMP improved after CABG both at rest (0.45 ± 0.11 before vs 0.38 ± 0.08 after CABG, P = 0.013) and during DSE (0.75 ± 0.23 vs 0.49 ± 0.14, P < 0.001). TAPSE declined significantly when comparing the values from before CABG to after CABG both at rest (23.9 ± 4.46 vs 14.6 ± 3.67, P < 0.001) and during DSE (20.9 ± 4.16 vs 11.9 ± 3.60, P < 0.001). RVS' also decreased after CABG both at rest (11.9 ± 2.40 vs 8.5 ± 1.93, P < 0.001) and during DSE (15.6 ± 4.30 vs 10.5 ± 3.21, P < 0.001). On the other hand, exercise capacity improved after CABG compared with baseline (128.4 ± 40.12 W vs 142.1 ± 46.73 W, P = 0.014). RIMP improved after CABG both at rest and during DSE. The reduction in TAPSE and RVS' after CABG indicate reduced regional mechanical RV function along the long axis rather than reduced global RV function.

Right Ventricular Functional Improvement after Pulmonary Rehabilitation Program in Patients with COPD Determined by Speckle Tracking Echocardiography.

BackgroundAlthough right ventricular (RV) dysfunction in pulmonary diseases has been associated with increased morbidity, tools for RV dysfunction identification are not well defined.ObjectiveThe aim of this study was to evaluate the magnitude of RV dysfunction by means of speckle tracking echocardiography (STE) in patients with chronic obstructive pulmonary disease (COPD) and to investigate whether STE could be used as an index of RV improvement after a pulmonary rehabilitation (PR) program.MethodsForty-six patients with COPD undergoing PR program and 32 age-sex matched healthy subjects were enrolled. RV function was evaluated at admission and after PR program by conventional two-dimensional echocardiography (2DE) and STE. In addition, exercise tolerance of subjects was evaluated using the six-minute walk test (6MWT).ResultsCOPD patients had worse RV function according to STE and 2DE as well. STE was more sensitive than conventional 2DE in determining RV improvement after PR program - RV global longitudinal strain (LS): 20.4 ± 2.4% vs. 21.9 ± 2.9% p < 0.001 and RV free wall LS: 18.1 ± 3.4% vs. 22.9 ± 3.7%, p < 0.001). RV free wall LS was directly related to distance walked at baseline 6MWT (r = 0.58, p < 0.001) and to the change in the 6MWT distance (6MWTD Δ) (r = 0.41, p = 0.04).ConclusionsWe conclude that STE might be as effective as 2DE for evaluation of global and regional RV functions. STE may become an important tool for assessment and follow-up of COPD patients undergoing PR program to determine the relationship between RV function and exercise tolerance.

Global and Regional Right Ventricular Function Assessed by Novel Three-Dimensional Speckle-Tracking Echocardiography

Accurate assessment of global and regional right ventricular (RV) systolic function is challenging. The aims of this study were to confirm the reliability and feasibility of a three-dimensional (3D) speckle-tracking echocardiography (STE) system, using comparison with cardiac magnetic resonance imaging (CMR), and to assess the contribution of regional RV function to global function. In a retrospective, cross-sectional study setting, RV volumetric data were studied in 106 patients who were referred for both CMR and 3D echocardiography within 1month. Three-dimensional STE-derived area strain, longitudinal strain, and circumferential strain were assessed as global, inlet, outflow, apical, and septal segments. Seventy-five patients (70%) had adequate 3D echocardiographic data. RV measurements derived from 3D STE and CMR were closely related (RV end-diastolic volume, R2=0.84; RV end-systolic volume, R2=0.83; RV ejection fraction [RVEF], R2=0.70; P<.001 for all). RVEF and RV end-diastolic volume from 3D STE were slightly but significantly smaller than CMR values (mean differences, -2% and -10mL for RVEF and RV end-diastolic volume, respectively). Among conventional echocardiographic parameters for RV function (tricuspid annular plane systolic excursion, fractional area change, S' of the tricuspid annulus, RV free wall two-dimensional longitudinal strain), only fractional area change was significantly related to RVEF (r=0.34, P=.003). Among segmental 3D strain variables, inlet area strain (r=-0.56, P<.001) and outflow circumferential strain (r=-0.42, P<.001) were independent factors associated with CMR-derived RVEF. RV volume and RVEF determined by 3D STE were comparable with CMR measurements. Regional RV wall motion showed that heterogeneous segmental deformations affect global RV function differently; specifically, inlet area strain and outflow circumferential strain were significant factors associated with RVEF in patients with underlying heart diseases.