Regional Right Ventricular Dysfunction Research Articles

Real-Time Strain-Encoding Cardiovascular MRI for Assessment of Regional Heart Function in Tetralogy of Fallot Patients.

Tetralogy of Fallot (ToF) is the most common form of cyanotic congenital heart disease, where right ventricular (RV) function is an important determinant of subsequent intervention. In this study, we evaluate the feasibility of fast strain-encoding (fastSENC; a one-heartbeat sequence) magnetic resonance imaging (MRI) for assessing regional cardiac function in ToF. FastSENC was implemented to characterize regional circumferential (Ecc) and longitudinal (Ell) strains in the left ventricle (LV) and RV in post-repair ToF. Data analysis was conducted to compare strain measurements in the RV to those in the LV, as well as to those generated by the MRI Tissue-Tracking (MRI-TT) technique, and to assess the relationship between strain and ejection fraction (EF). Despite normal LVEF (55±8.5%), RVEF was borderline (46±6.4%), but significantly lower than LVEF. RV strains (RV-Ell=-20.2±2.9%, RV-Ecc=-15.7±6.4%) were less than LV strains (LV-Ell=-21.7±3.7%, LV-Ecc=-18.3±4.7%), and Ell was the dominant strain component. Strain differences between fastSENC and MRI-TT were less significant in RV than in LV. There existed moderate and weak correlations for RV-Ecc and RV-Ell, respectively, against RVEF. Compared to LV strain, RV strain showed regional heterogeneity with a trend for reduced strain from the inferior to anterior regions. Inter-ventricular strain delay was larger for Ell (64±47ms) compared to Ecc (36±40ms), reflecting a trend for contraction dyssynchrony. FastSENC allows for characterizing subclinical regional RV dysfunction in ToF. Due to its sensitivity for evaluating regional myocardial contractility patterns and real-time imaging capability without the need for breath-holding, fastSENC makes it more suitable for evaluating RV function in ToF.

Regional shape, global function and mechanics in right ventricular volume and pressure overload conditions: a three-dimensional echocardiography study

Our aim was to assess the regional right ventricular (RV) shape changes in pressure and volume overload conditions and their relations with RV function and mechanics. The end-diastolic and end-systolic RV endocardial surfaces were analyzed with three-dimensional echocardiography (3DE) in 33 patients with RV volume overload (rToF), 31 patients with RV pressure overload (PH), and 60 controls. The mean curvature of the RV inflow (RVIT) and outflow (RVOT) tracts, RV apex and body (both divided into free wall (FW) and septum) were measured. Zero curvature defined a flat surface, whereas positive or negative curvature indicated convexity or concavity, respectively. The longitudinal and radial RV wall motions were also obtained. rToF and PH patients had flatter FW (body and apex) and RVIT, more convex interventricular septum (body and apex) and RVOT than controls. rToF demonstrated a less bulging interventricular septum at end-systole than PH patients, resulting in a more convex shape of the RVFW (r = − 0.701, p < 0.0001), and worse RV longitudinal contraction (r = − 0.397, p = 0.02). PH patients showed flatter RVFW apex at end-systole compared to rToF (p < 0.01). In both groups, a flatter RVFW apex was associated with worse radial RV contraction (r = 0.362 in rToF, r = 0.482 in PH at end-diastole, and r = 0.555 in rToF, r = 0.379 in PH at end-systole, respectively). In PH group, the impairment of radial contraction was also related to flatter RVIT (r = 0.407) and more convex RVOT (r = − 0.525) at end-systole (p < 0.05). In conclusion, different loading conditions are associated to specific RV curvature changes, that are related to longitudinal and radial RV dysfunction.

P4365Role of 3D speckle-tracking echocardiography system, using comparison with cardiac magnetic resonance imaging and to assess the contribution of regional RV function to global function in COPD patients

Abstract Background Chronic obstructive pulmonary disease may alter right and left ventricular function by changing intrathoracic pressure. Pulmonary hyperinflation may increase right atrial pressure, leading to reduced venous return and subsequent reductions in RV pre-load. In COPD patients, hyperinflation has been directly correlated with reduced atrial chamber size, global RV dysfunction, and reduced LV filling. Accurate assessment of global and regional right ventricular (RV) systolic function is challenging. Purpose 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. Methods In a retrospective, cross-sectional study setting, RV volumetric data were studied in 302 patients who were referred for both CMR and 3D echocardiography within 1 month. Three-dimensional STE-derived area strain, longitudinal strain, and circumferential strain were assessed as global, inlet, outflow, apical, and septal segments. Results 208 patients (69%) had adequate 3D echocardiographic data. RV measurements derived from 3D STE and CMR were closely related (RV end-diastolic volume, R2=0.88; RV end-systolic volume, R2=0.81; RV ejection fraction [RVEF], R2=0.69; P&lt;0.004 for all). RVEF and RV end-diastolic volume from 3D STE were slightly but significantly smaller than CMR values (mean differences, −2.8% and −7.8 mL 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=0.29, P=0.003). Among segmental 3D strain variables, inlet area strain (r=−0.48, P&lt;0.002) and outflow circumferential strain (r=−0.37, P&lt;0.003) were independent factors associated with CMR-derived RVEF. Conclusions Regional RV wall motion showed that heterogeneous segmental deformations affect global RV function differently; specifically, inlet area strain and outflow circumferential strain.RV volume and RVEF determined by STE were comparable with CMR measurements. Severity of COPD influences RV systolic dysfunction, which is reflected in speckle tracking 3D echocardiographic parameters.

P4356Assessment of global and regional right ventricular systolic function in restrictive pulmonary disease by novel speckle tracking 3D echocardiography comparison with cardiac magnetic resonance imaging

Abstract Background Chronic restrictive pulmonary disease may alter right and left ventricular function by changing intrathoracic pressure. Pulmonary hyperinflation may increase right atrial pressure, leading to reduced venous return and subsequent reductions in RV pre-load. In CRPD patients, hyperinflation has been directly correlated with reduced atrial chamber size, global RV dysfunction, and reduced LV filling. Accurate assessment of global and regional right ventricular (RV) systolic function is challenging. Purpose 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. Methods In a retrospective, cross-sectional study setting, RV volumetric data were studied in 200 patients who were referred for both CMR and 3D echocardiography within 1 month. Three-dimensional STE-derived area strain, longitudinal strain, and circumferential strain were assessed as global, inlet, outflow, apical, and septal segments. Results 136 patients (68%) had adequate 3D echocardiographic data. RV measurements derived from 3D STE and CMR were closely related (RV end-diastolic volume, R2=0.89; RV end-systolic volume, R2=0.82; RV ejection fraction [RVEF], R2=0.68; P&lt;0.003 for all). RVEF and RV end-diastolic volume from 3D STE were slightly but significantly smaller than CMR values (mean differences, −3% and −8 mL 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=0.30, P=0.005). Among segmental 3D strain variables, inlet area strain (r=−0.49, P&lt;0.004) and outflow circumferential strain (r=−0.39, P&lt;0.005) were independent factors associated with CMR-derived RVEF. Conclusions Severity of restrictive pulmonary disease influences RV systolic dysfunction, which is reflected in speckle tracking 3D echocardiographic parameters. Regional RV wall motion showed that heterogeneous segmental deformations affect global RV function differently; specifically, inlet area strain and outflow circumferential strain.RV volume and RVEF determined by STE were comparable with CMR measurements.

P615Role of 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

Abstract Background Chronic obstructive pulmonary disease may alter right and left ventricular function by changing intrathoracic pressure. Pulmonary hyperinflation may increase right atrial pressure, leading to reduced venous return and subsequent reductions in RV pre-load. In COPD patients, hyperinflation has been directly correlated with reduced atrial chamber size, global RV dysfunction, and reduced LV filling. Accurate assessment of global and regional right ventricular (RV) systolic function is challenging. Purpose 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. Methods In a retrospective, cross-sectional study setting, RV volumetric data were studied in 302 patients who were referred for both CMR and 3D echocardiography within 1 month. Three-dimensional STE-derived area strain, longitudinal strain, and circumferential strain were assessed as global, inlet, outflow, apical, and septal segments. Results 208 patients (69%) had adequate 3D echocardiographic data. RV measurements derived from 3D STE and CMR were closely related (RV end-diastolic volume, R2=0.88; RV end-systolic volume, R2=0.81; RV ejection fraction [RVEF], R2=0.69; P&lt;0.004 for all). RVEF and RV end-diastolic volume from 3D STE were slightly but significantly smaller than CMR values (mean differences, −2.8% and −7.8 mL 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=0.29, P=0.003). Among segmental 3D strain variables, inlet area strain (r=−0.48, P&lt;0.002) and outflow circumferential strain (r=−0.37, P&lt;0.003) were independent factors associated with CMR-derived RVEF. Conclusions Regional RV wall motion showed that heterogeneous segmental deformations affect global RV function differently; specifically, inlet area strain and outflow circumferential strain.RV volume and RVEF determined by STE were comparable with CMR measurements. Severity of COPD influences RV systolic dysfunction, which is reflected in speckle tracking 3D echocardiographic parameters.

Abstract 10293: Regional Right Ventricular Dysfunction in Acute Pulmonary Embolism Associated With Increased Clot Burden and Greater RV Dysfunction

Introduction: Regional right ventricular (RV) dysfunction (RRVD) is an echocardiographic feature in acute pulmonary embolism (PE), primarily reported in patients with moderate-to-severe RV dysfunction. We assessed the hypothesis that RRVD is associated with increased burden of PE and greater RV dysfunction. Methods: We identified all consecutive patients admitted at Stanford’s emergency department between 1999 and 2014 who underwent both computed tomographic angiography, echocardiography, and biomarker testing (troponin and NT-proBNP) within 2 days of each other for suspected acute PE, in order to investigate the relationship between RRVD, PE clot burden, RV size/function, and biomarkers. Patients with PE were divided according to clot burden as follows: central or multilobar PE versus peripheral PE. RRVD was defined as normal excursion of the apex contrasting with hypokinesis of the mid-free wall segment. RV function was assessed by fractional area change and free-wall longitudinal strain. Echocardiograms were also assessed for reproducibility. Results: Eighty-two patients were included (mean age 66 ±17 years, 43% male, 51 with acute PE). RRVD was present in 41% of PEs and absent in all patients without PE. Eighty-six percent (86%) of patients with RRVD had central or multi-lobar PE. Patients with RRVD had higher prevalence of moderate-to-severe RV dilation (81% vs. 30%, p&lt;0.01) and dysfunction (86% vs. 23%, p&lt;0.01). Troponin level was positive in 38% of patients with RRVD versus 13% in PE without RRVD (p=0.08), while the NT-proBNP level was positive in 67% versus 73% (p=0.88), respectively. RRVD showed excellent concordance between readers (87%). Conclusion: The “McConnell sign” of RRVD is a reproducible finding associated with an increased clot burden and greater degree of RV dysfunction in patients with acute PE.

Right Ventricular Strain and Dyssynchrony Assessment in Arrhythmogenic Right Ventricular Cardiomyopathy: Cardiac Magnetic Resonance Feature-Tracking Study.

Analysis of right ventricular (RV) regional dysfunction by cardiac magnetic resonance (CMR) imaging in arrhythmogenic RV cardiomyopathy (ARVC) may be inadequate because of the complex contraction pattern of the RV. Aim of this study was to determine the use of RV strain and dyssynchrony assessment in ARVC using feature-tracking CMR analysis. Thirty-two consecutive patients with ARVC referred to CMR imaging were included. Thirty-two patients with idiopathic RV outflow tract arrhythmias and 32 control subjects, matched for age and sex to the ARVC group, were included for comparison purpose. CMR imaging was performed to assess biventricular function; feature-tracking analysis was applied to the cine CMR images to assess regional and global longitudinal, circumferential, and radial RV strains and RV dyssynchrony (defined as the SD of the time-to-peak strain of the RV segments). RV global longitudinal strain (-17±5% versus -26±6% versus -29±6%; P<0.001), global circumferential strain (-9±4% versus -12±4% versus -13±5%; P=0.001), and global radial strain (18 [12-26]% versus 22 [15-32]% versus 27 [20-39]%; P=0.015) were significantly lower and SD of the time-to-peak RV strain in all 3 directions were significantly higher among patients with ARVC compared with patients with RV outflow tract arrhythmias and controls. RV global longitudinal strain >-23.2%, SD of the time-to-peak RV longitudinal strain >113.1 ms, and SD of the time-to-peak RV circumferential strain >177.1 ms allowed correct identification of 88%, 75%, and 63% of ARVC patients with no or only minor CMR criteria for ARVC diagnosis. Strain analysis by feature-tracking CMR helps to objectively quantify global and regional RV dysfunction and RV dyssynchrony in patients with ARVC and provides incremental value over conventional cine CMR imaging.

Regional right ventricular dysfunction in acute pulmonary embolism: relationship with clot burden and biomarker profile.

Regional right ventricular (RV) dysfunction (RRVD) is an echocardiographic feature in acute pulmonary embolism (PE), primarily reported in patients with moderate-to-severe RV dysfunction. This study investigated the clinical importance of RRVD by assessing its relationship with clot burden and biomarkers. We identified consecutive patients admitted to the emergency department between 1999 and 2014 who underwent computed tomographic angiography, echocardiography, and biomarker testing (troponin and NT-proBNP) for suspected acute PE. RRVD was defined as normal excursion of the apex contrasting with hypokinesis of the mid-free wall segment. RV assessment included measurements of ventricular dimensions, fractional area change, free-wall longitudinal strain and tricuspid annular plane systolic excursion. Clot burden was assessed using the modified Miller score. Of 82 patients identified, 51 had acute PE (mean age 66 ± 17 years, 43% male). No patient had RV myocardial infarction. RRVD was present in 41% of PEs and absent in all patients without PE. Among patients with PE, 86% of patients with RRVD had central or multi-lobar PE. Patients with RRVD had higher prevalence of moderate-to-severe RV dilation (81 vs. 30%, p < 0.01) and dysfunction (86 vs. 23%, p < 0.01). There was a strong trend for higher troponin level in PE patients with RRVD (38 vs. 13% in PE patients without RRVD, p = 0.08), while there was no significant difference for NT-proBNP (67 vs. 73%, p = 0.88). RRVD showed good concordance between readers (87%). RRVD is associated with an increased clot burden in acute PE and is more prevalent among patients with moderate-to-severe RV enlargement and dysfunction.

Right ventricular function quantification in Takotsubo cardiomyopathy using two-dimensional strain echocardiography.

AimsThis study sought to characterize global and regional right ventricular (RV) myocardial function in patients with Takotsubo cardiomyopathy (TC) using 2D strain imaging.MethodsWe compared various parameters of RV and left ventricular (LV) systolic function between 2 groups of consecutive patients with TC at initial presentation and upon follow-up. Group 1 had RV involvement and group 2 did not have RV involvement.ResultsAt initial presentation, RV peak systolic longitudinal strain (RVPSS) and RV fractional area change (RVFAC) were significantly lower in group 1 (−13.2±8.6% vs. −21.8±5.4%, p = 0.001; 30.7±9.3% vs. 43.5±6.3%, p = 0.001) and improved significantly upon follow-up. Tricuspid annular plane systolic excursion (TAPSE) did not differ significantly at initial presentation between both groups (14.8±4.1 mm vs. 17.9±3.5 mm, p = 0.050). Differences in regional systolic RV strain were only observed in the mid and apical segments. LV ejection fraction (LVEF) and LV global strain were significantly lower in group 1 (36±8% vs. 46±10%, p = 0.006 and −5.5±4.8% vs. −10.2±6.2%, p = 0.040) at initial presentation. None of the parameters were significantly different between the 2 groups upon follow-up. A RVPSS cut-off value of >−19.1% had a sensitivity of 85% and a specificity of 71% to discriminate between the 2 groups.ConclusionIn TC, RVFAC, RVPSS, LVEF and LV global strain differed significantly between patients with and without RV dysfunction, whereas TAPSE did not. 2 D strain imaging was feasible for the assessment of RV dysfunction in TC and could discriminate between patients with and without RV involvement in a clinically meaningful way.

Comprehensive Assessment of Right Ventricular Function in Patients with Pulmonary Hypertension with Global Longitudinal Peak Systolic Strain Derived from Multiple Right Ventricular Views

Right ventricular (RV) function is a strong predictor of mortality in pulmonary hypertension (PH), but two-dimensional (2D) echocardiography-derived assessments of RV function that could aid in risk assessment and management of patients with PH are of limited utility. RV longitudinal peak systolic strain (RVLS) derived from 2D speckle-tracking echocardiography is a relatively novel method for quantifying RV function but typically is derived from a single apical four-chamber view of the right ventricle and may have inherent limitations. The objective of this study was to determine the utility of regional and global RVLS calculated from multiple views of the right ventricle to comprehensively assess RV function in a cohort of patients with PH. Regional and global RVLS were obtained from multiple views of the right ventricle (centered on the right ventricle-focused apical position) in 40 patients with PH, defined as a mean pulmonary artery pressure ≥25 mm Hg, most of whom also had pulmonary capillary wedge pressures ≤ 15 mm Hg and were thus defined as having pulmonary arterial hypertension. This was compared with other 2D echocardiography-derived parameters of RV function and functional parameters. Global RVLS calculated from multiple views had a superior correlation with 6-min walk distance compared with other parameters of RV function, including tricuspid annular plane systolic excursion, RV myocardial performance index, and fractional area change. Although global RVLS calculated from multiple views displayed a similar correlation with 6-min walk distance as global RVLS calculated from a single four-chamber view, analysis of regional strains provided by multiple views identified distinct patterns of RV dysfunction, consisting of global, free wall, or septal dysfunction, that were associated with specific clinical characteristics. Global RVLS derived from multiple right ventricle-focused views yields a comprehensive quantitative assessment of regional and global RV function that correlates moderately with functional parameters and may be useful in the assessment of PH. Distinct patterns of regional RV dysfunction are associated with different clinical characteristics.

Effects of endoscopic lung volume reduction on right ventricular myocardial function in patients with advanced emphysema

Endoscopic lung volume reduction (ELVR) using endobronchial valve implantation provides a minimally invasive, effective technique for patients with severe progressive and irreversible lung emphysema. However, its impact on right ventricular (RV) function is unknown. We therefore assessed the extent of global and regional RV dysfunction in patients undergoing ELVR by use of speckle tracking echocardiography based on RV deformation analysis and correlated the results with the clinical outcomes using exercise capacity testing and Nt-proBNP-levels.

Functional analysis of the anatomical right ventricular components: should assessment of right ventricular function after repair of tetralogy of Fallot be refined?

Follow-up after tetralogy of Fallot (ToF) repair is directed to detect timely right ventricular (RV) dysfunction by following pulmonary regurgitation and global RV size, with little attention for the effective contribution of regional RV dysfunction. This study investigates the contribution of regional RV dysfunction on exercise capacity after ToF repair. Forty-two patients were investigated with cardiac magnetic resonance imaging for regional RV dysfunction in relation to global RV function by functional quantification of the sinus and outflow part of the RV. The impact of regional and global RV dysfunction on clinical status was studied by exercise testing. Global RV function was lower than sinus function (ejection fraction (EF) 52±12% vs 58±10%, P<0.001), attributable to the adverse influence of right ventricular outflow tract (RVOT) dysfunction (EF 34±17%). Percent predicted peak VO2 correlated better with the RV sinus ejection fraction compared with the global RV ejection fraction (r=0.51, P=0.001 vs r=0.44, P=0.004). Multivariate analysis revealed the EF of RV sinus (β=0.34, 95% CI 0.07-0.61, P=0.013) and the extent of RVOT akinesia (β=-0.28, 95% CI -0.50; -0.06, P=0.015) as significant determinants of exercise capacity. Impaired exercise performance occurred in 43% of the patients, and was independently determined by the type of repair (transventricular vs transatrial: OR 6.0, 95% CI 1.31-17.3, P=0.02) by associating greater sinus and RVOT dysfunction. Functional analysis of the RV components shows that exercise capacity after repair of ToF is better predicted by systolic function of the RV sinus as the extent of RVOT dysfunction commonly leads to underestimation of global RV function. This method of differential quantification of regional RV function might be more appropriate than assessment of global RV function during the long-term follow-up of repaired ToF patients.

Global and Regional Right Ventricular Dysfunction in Pulmonary Hypertension

Pulmonary hypertension (PH) is known to affect the right ventricular (RV) function. To assess the extent of global and regional RV dysfunction in PH patients. We performed a cross-sectional study on 20 controls (age 62 ± 15 years, 7 males) and 35 patients (age 67 ± 12 years, 13 males) with PH of mixed etiologies and assessed RV inflow and outflow tracts (OTs) function, using speckle tracking echocardiography (STE) based myocardial deformation and its time relations. RV inlet and OT dimensions (2D), inlet myocardial velocities (TDI), myocardial strain and strain rate (SR), TAPSE (M-mode), ejection and filling times (pulsed-wave [PW] Doppler), and pulmonary artery acceleration (PAc) were measured. RV inlet and OT were dilated (P < 0.001 for both) and TAPSE (P < 0.001), inlet velocities (P < 0.001), basal and mid-cavity strain, SR and longitudinal displacement reduced (P < 0.001 for all). The time to peak systolic SR at basal, mid-cavity (P < 0.001 for both), and RVOT (P = 0.007) was short as was that to peak displacement (P < 0.001 for all). The time to peak pulmonary ejection correlated with time to peak SR at RVOT (r = 0.7, P < 0.001) in controls, but with that of the mid-cavity in patients (r = 0.71, P < 0.001). PAc was faster (P = 0.001) and RV filling time shorter in patients (P = 0.03) with respect to controls. PH has drastic effects on RV structure and intrinsic myocardial function, significantly disturbing its ejection time relations and overall pump performance. Increased RV afterload results in RV configuration changes with the inflow tract determining peak ejection rather than OT.

Regional and Global Biventricular Function in Pulmonary Arterial Hypertension: A Cardiac MR Imaging Study

To determine whether chronic pulmonary arterial pressure (PAP) elevation affects regional biventricular function and whether regional myocardial function may be reduced in pulmonary arterial hypertension (PAH) patients with preserved global right ventricular (RV) function. After informed consent, 35 PAH patients were evaluated with right heart catheterization and cardiac magnetic resonance (MR) imaging and compared with 13 healthy control subjects. Biventricular segmental, section, and mean ventricular peak systolic longitudinal strain (E(LL)), as well as left ventricular (LV) circumferential and RV tangential strains were compared between PAH patients and control subjects and correlated with global function and catheterization of the right heart indexes. Spearman ρ correlation with Bonferroni correction was used. Multiple linear regression analysis was performed to determine predictors for regional myocardial function. In the RV of PAH patients, longitudinal contractility was reduced at the basal, mid, and apical levels, and tangential contractility was reduced at the midventricular level. Mean RV E(LL) positively correlated with mean PAP (r = 0.62, P < .0014) and pulmonary vascular resistance index (PVRI) (r = 0.77, P < .0014). Mean PAP was a predictor of mean RV E(LL) (β = .19, P = .005) in a multiple linear regression analysis. In the LV, reduced LV longitudinal and circumferential contractility were noted at the base. LV anteroseptal E(LL) positively correlated with increased mean PAP (r = 0.5, P = .03) and septal eccentricity index (r = 0.5, P = .01). In a subgroup of PAH patients with normal global RV function, significantly reduced RV longitudinal contractility was noted at basal and mid anterior septal insertions, as well as the mid anterior RV wall (P < .05 for all). In PAH patients, reduced biventricular regional function is associated with increased RV afterload (mean PAP and PVRI). Cardiac MR imaging helps identify regional RV dysfunction in PAH patients with normal global RV function. http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12111599/-/DC1.

Regional Right Ventricular Strain Pattern in Patients with Acute Pulmonary Embolism

Right ventricular (RV) dysfunction is a frequent consequence of pulmonary embolism (PE) and a marker of increased risk. However, current qualitative methods assessing RV function are imprecise. We sought to determine whether RV strain analysis would have clinical utility in patients with PE compared with normal controls. We compared 75 acute PE subjects (mean age 54 ± 16) with 30 normal controls (mean age 50 ± 15). Regional RV longitudinal strain was assessed using offline speckle tracking software to obtain strain and strain rate data from the basal, mid, and apical free wall and septum. Global RV free wall and septal strain was significantly reduced in PE subjects (-14.17 (±5.96) vs -24.92 (±4.16), P < 0.0001; -14.99 (±5.55) vs -18.54 (±7.34), P = 0.0082). Regional RV strain was markedly reduced in PE subjects in all regions of the free wall and in the mid and basal septum (P < 0.05). Strain rates of PE subjects were significantly reduced in all segments of the RV free wall (P < 0.05). In 36 PE subjects with regional RV dysfunction ("McConnell sign"), strain in the apical free wall was significantly reduced in comparison to those without (-10.08 vs -13.51; P = 0.0420), in parallel with higher RV:LV ratios (1.30, ±1.01 vs 0.78, ±0.16; P = 0.0035) and lower RV fractional area change (32.06, ±14.42 vs 42.52, ±11.61; P = 0.0021). Regional RV longitudinal strain is altered in the free wall and mid and basal septum in subjects with acute PE. Strain rates are only reduced in the RV free wall.

Right ventricular strain rate predicts clinical outcomes in patients with acute pulmonary embolism

Echocardiographic quantification of global and regional right ventricular (RV) function is critical in patients with acute pulmonary embolism (PE), but remains a challenge particularly in acute RV dilatation. Apical two-dimensional images of patients with acute PE were analyzed using both conventional and speckle tracking imaging compared with controls; patients with PE were divided into those who received thrombolysis and those who did not. The basal, mid and apical segments of the RV free wall and septum were analyzed. Correlations between speckle tracking measurements and in-hospital mortality were made. 53 patients with PE were compared with 15 controls. Of the PE patients, 98.1% were treated with systemic anticoagulation, 15.1% with thrombolysis; 38% required ICU admission and 5.6% died. Strain rate of the mid interventricular septum and strain of the basal and mid interventricular septal segments were significantly lower in patients with PE than control. However, strain rate of the basal RV free wall was higher than controls. In thrombolysed patients, basal RV free wall strain rate was lower than in non-thrombolysed patients. RV strain rate significantly correlated with in-hospital mortality. Speckle tracking may be a sensitive tool for assessing RV dysfunction and predicting mortality in patients with PE in this pilot study.

Regional right ventricular deformation in patients with open and closed atrial septal defect

This study aimed at (i) evaluating regional right ventricular (RV) deformation in patients with an atrial septal defect (ASD)-type secundum using strain and strain rate imaging and (ii) investigating the relation of regional deformation with functional capacity using cardiopulmonary exercise testing (CPET) in order to identify subclinical changes in RV function. Forty-five patients with ASD-type secundum (18 open, 27 closed) and 20 age-matched controls were included. All underwent standard echocardiography and colour-Doppler myocardial velocity imaging. Longitudinal deformation was measured in the RV free wall divided in two segments. ASD patients underwent symptom-limited CPET. When compared with controls, apical strain was higher (-38.2 ± 9.9 vs. -29.9 ± 6.6%; P= 0.004) and lower (-25.2 ± 6.1 vs. -29.9 ± 6.6%; P= 0.006) in patients with an open and a closed ASD, respectively. Apical strain was higher (-38.2 ± 9.9 vs. -27.9 ± 6.6%; P= 0.001) and lower (-25.2 ± 6.1 vs. -28.7 ± 7.4%; P= 0.022) than basal strain in patients with an open and a closed ASD, respectively. In patients with an open ASD, apical strain correlated with shunt-ratio (R = -0.78; P< 0.0001), RV end-diastolic area (R = -0.68; P= 0.002), and RV stroke volume (R = -0.67; P= 0.002). Peak oxygen consumption (peak vO₂) was below average in patients with an open (79 ± 19% predicted; P< 0.0001) and a closed ASD (89 ± 18% predicted; P= 0.002). After ASD repair, apical strain correlated with peak vO₂ (R = -0.49; P= 0.01) and with ventilatory efficiency (R = 0.62; P= 0.001). Volume overload of the right ventricle in patients with ASD-type secundum causes a regional deformation pattern with higher apical strain, related to parameters of volume load severity. After ASD repair, lower apical strain values correlated with functional capacity. Measurement of apical strain seems sensitive for detecting mild RV dysfunction.

Reconciling the Protean Manifestations of Arrhythmogenic Cardiomyopathy

Medical conception of a disease begins with in vivo observation and develops with recognition of cognate findings on gross anatomy, histology, and cellular pathology. It was histopathology that established myocyte disarray as the cardinal feature of hypertrophic cardiomyopathy, present even in cases where left ventricular (LV) hypertrophy is subtle or absent. To this day, clinical-pathological association retains its historical value as the primary means of gaining insight into underlying disease processes. Enhancing its appeal is its accessibility to physicians, most of whom are familiar with histopathology from medical school and attuned to visual diagnosis. Article see p 632 With the advent of molecular genetics, however, the limitations of clinical-pathological association have become apparent and nowhere more so than in the inherited arrhythmia syndromes. In the long-QT and Brugada syndromes and catecholaminergic polymorphic ventricular tachycardia, a structurally normal heart belies the propensity to ventricular arrhythmia and sudden cardiac death (SCD). How this might be possible began to unravel with the isolation of mutations in genes encoding ion channels, transporters, and binding proteins. Genetic studies also have provided fresh insights into diseases with an obvious pathological substrate, such as hypertrophic cardiomyopathy, in which sarcomeric mutations predominate. Families with a high incidence of SCD and myocyte disarray but minimal LV hypertrophy were found to have mutations in troponin T,1 lending further support to the inclusion of this phenotype within the spectrum of hypertrophic cardiomyopathy. Redefining diseases according to their genetic etiology, while attractive, is less straightforward than immediately obvious. Defects in sarcomeric components, for example, have been implicated in both hypertrophic cardiomyopathy and dilated cardiomyopathy. In some heritable disorders, such as dilated cardiomyopathy, marked locus heterogeneity precludes delineation of a single genetic determinant. The ultimate solution to disease classification involves going 1 step further and identifying a unifying molecular mechanism, which may …

Noninvasive Diagnosis of Electroanatomic Abnormalities in Arrhythmogenic Right Ventricular Cardiomyopathy

The diagnostic reliability and pathophysiologic relevance of different noninvasive diagnostic criteria for arrhythmogenic right ventricular cardiomyopathy (ARVC) are undefined. We tested the association between noninvasive diagnostic criteria for ARVC and the presence of low-voltage areas (LVAs) detected at electroanatomic voltage mapping (EAM). Noninvasive diagnostic criteria, including ECG, signal-averaged ECG (SAECG), and cardiac magnetic resonance (CMR) criteria, were compared with the presence and location of LVAs detected at right ventricular (RV) EAM in 17 patients (9 men) aged 50 ± 16 years with biopsy specimen-proven ARVC. LVAs were found in 15 (88%) patients. Patients with surface ECG abnormalities showed a higher degree of RV involvement than those without ECG abnormalities (number of LVAs, 1.8 ± 0.5 versus 0.9 ± 0.6, respectively; P < 0.01). A significant association was found between SAECG abnormalities and LVAs in the RV outflow tract (P = 0.03) but not between SAECG parameters and LVAs in other RV regions. Among CMR findings, RV delayed enhancement was more significantly associated with the distribution of LVAs (free wall, P < 0.01; outflow tract, P < 0.01; posteroinferior wall, P = 0.02). Regional RV dysfunction also showed a good correlation with LVAs, with the most significant association being found with the free wall (P = 0.01), whereas RV fat infiltration at CMR was not correlated with LVAs. In patients with ARVC, SAECG abnormalities correlate with the presence of LVAs selectively in the RV outflow tract, whereas surface ECG abnormalities are associated with a more diffuse RV involvement. Myocardial delayed enhancement is the CMR finding more strongly associated with LVAs, thus supporting the appropriateness of its inclusion among diagnostic criteria for ARVC.

Timing and Magnitude of Regional Right Ventricular Function: A Speckle Tracking-Derived Strain Study of Normal Subjects and Patients with Right Ventricular Dysfunction

The aim of this study was to evaluate the timing and magnitude of global and regional right ventricular (RV) function by means of speckle tracking-derived strain in normal subjects and patients with RV dysfunction. Peak longitudinal systolic strain (PLSS) and time to PLSS in 6 RV segments (the basal, mid, and apical segments of the RV free wall and septum) were obtained in 100 healthy volunteers and 76 patients with RV dysfunction by tracking speckles inside the myocardium using grayscale images. Global PLSS and time to PLSS were based on the average of the 6 regional values. There was a significant and close correlation between RV contractility as measured by PLSS and tricuspid annular plane systolic excursion (r = -0.83, P < .001). In normal subjects, PLSS was significantly greater in the free wall than in the septum (-28.7 + or - 4.1% vs -19.8 + or - 3.4%, P < .001), whereas time to PLSS was similar in the different regions of the right ventricle. In patients with RV dysfunction, global and regional PLSS was significantly less than in normal subjects (-13.7 + or - 3.6% vs -24.2 + or - 2.9%, P < .001), and a global PLSS cutoff value of -19% was helpful in distinguishing the two groups. Furthermore, time to PLSS in all of the RV septal segments and dispersion in RV contraction timing were significantly longer. Global PLSS in the patients with RV dysfunction was also significantly less in the presence of moderate to severe pulmonary hypertension (-12.7 + or - 3.6% vs -14.4 + or - 3.4%, P = .038). Speckle tracking not only makes it possible to quantify global RV function but also illustrates the physiology of RV contraction and the pattern of activation at regional level. Speckle tracking-derived strain could become an important new means of assessing and following up patients with impaired RV function and increased pulmonary pressure.