Right ventricular function in hypertrophic cardiomyopathy: A speckle tracking echocardiography study

Feasibility Value of Right Ventricular Longitudinal Shortening Fraction and the Prognostic Implications in Patients With Heart Transplantation

BACKGROUND

Right ventricular longitudinal shortening fraction (RVLSF) is a 2-dimensional speckle tracking echocardiography parameter based on tricuspid annular displacement analysis that could be used to assess right ventricular (RV) systolic function. The value of RVLSF in the assessment of RV systolic function in recipients of heart transplantation (HT) and whether RVLSF can replace strain parameters remains unknown.

METHODS AND RESULTS

A total of 153 adult patients who underwent HT were consecutively enrolled in this prospective longitudinal study. All subjects were examined by conventional transthoracic 2-dimensional echocardiography and 2-dimensional speckle tracking echocardiography to evaluate the RV end-diastolic basal diameter, RV end-diastolic area, fractional area change, peak systolic velocity of tricuspid annulus, tricuspid annular plane systolic excursion, RV free wall strain, and RVLSF. Cox proportional hazards regression was used to test if the parameters of interest had independent prognostic value for adverse outcome prediction in patients who underwent HT. A significant positive correlation was found between the measurements of RVLSF and RV free wall strain (r=0.927, P<0.001). Compared with the event-free group, the adverse outcome group displayed reduced RVLSF and RV free wall strain and higher age (P<0.001, <0.001, =0.016, respectively) in patients who underwent HT. RVLSF and RV free wall strain were independently associated with poor prognosis in multivariable analysis (both P<0.001).

CONCLUSIONS

RVLSF assessment provides an effective evaluation of RV longitudinal systolic function in the transplanted hearts and has prognostic value for adverse outcomes in patients undergoing HT.

Right ventricular function declines prior to left ventricular ejection fraction in hypertrophic cardiomyopathy

BACKGROUND

The right ventricle (RV) in hypertrophic cardiomyopathy (HCM) tends to be neglected, as previous efforts have predominantly focused on examining the prognostic value of left ventricular (LV) abnormalities. The objectives of this study were to assess RV function in HCM, changes over time, and association with clinical outcomes.

METHODS

Two hundred and ninety HCM patients with preserved LV ejection fraction (LVEF ≥ 55%) and 30 age- and sex-matched controls underwent cardiovascular magnetic resonance (CMR). All patients were followed up for clinical events for a median duration of 4.4 years. Sixty-three patients had a follow-up CMR undertaken at a median interval of 5.4 years. Main study measures and outcomes were RV function (RV ejection fraction (RVEF) and RV strain) at baseline, temporal changes in RV function over time and prognostic value of RV dysfunction for predicting cardiovascular outcomes in HCM.

RESULTS

When compared to controls, HCM patients exhibited lower RV and LV peak global longitudinal systolic strains on feature-tracking analysis of cine images, while RVEF and LVEF were within the normal range. On follow-up CMR, both RV and LV strain parameters decreased over time. RVEF decreased at follow-up (65 ± 7% to 62 ± 7%, P < 0.001) but the change in LVEF was not significant (68 ± 10% to 66 ± 8%, P = 0.30). On clinical follow up, reduced RVEF was an independent predictor of non-sustained ventricular tachycardia (NSVT) [HR 1.10 (95% CI 1.06-1.15), P < 0.001] and composite cardiovascular events (NSVT, stroke, heart failure hospitalisation and cardiovascular death) [HR 1.07 (95% CI 1.03-1.10), P < 0.001]. RV longitudinal strain was an independent predictor of NSVT [HR 1.05 (95% CI 1.01-1.09), P = 0.029]. Patients with RVEF < 55% showed an increased risk of NSVT and composite cardiovascular events. In contrast, LVEF and LV global longitudinal strain were not predictive of such events on multivariable analysis.

CONCLUSIONS

In HCM, RV function, including RV strain, and LV strain decrease over time despite preserved LVEF. Reduction in RV but not LV function is associated with adverse cardiovascular outcomes. Assessing RV function in early HCM disease might have a role in risk stratification to prevent future cardiovascular events.

The Prognostic Importance of Right Ventricular Longitudinal Strain in Patients with Cardiomyopathies, Connective Tissue Diseases, Coronary Artery Disease, and Congenital Heart Diseases

Right ventricular (RV) systolic function represents an important independent predictor of adverse outcomes in many cardiovascular (CV) diseases. However, conventional parameters of RV systolic function (tricuspid annular plane excursion (TAPSE), RV myocardial performance index (MPI), and fractional area change (FAC)) are not always able to detect subtle changes in RV function. New evidence indicates a significantly higher predictive value of RV longitudinal strain (LS) over conventional parameters. RVLS showed higher sensitivity and specificity in the detection of RV dysfunction in the absence of RV dilatation, apparent wall motion abnormalities, and reduced global RV systolic function. Additionally, RVLS represents a significant and independent predictor of adverse outcomes in patients with dilated cardiomyopathy (CMP), hypertrophic CMP, arrhythmogenic RV CMP, and amyloidosis, but also in patients with connective tissue diseases and patients with coronary artery disease. Due to its availability, echocardiography remains the main imaging tool for RVLS assessment, but cardiac magnetic resonance (CMR) also represents an important additional imaging tool in RVLG assessment. The findings from the large studies support the routine evaluation of RVLS in the majority of CV patients, but this has still not been adopted in daily clinical practice. This clinical review aims to summarize the significance and predictive value of RVLS in patients with different types of cardiomyopathies, tissue connective diseases, and coronary artery disease.

Right ventricular involvement in hypertrophic cardiomyopathy: evidence and implications from current literature

Objectives. In current guidelines, hypertrophic cardiomyopathy (HCM) is defined by hypertrophy of the left ventricle (LV). Less attention has been given to the right ventricle (RV) in patients with HCM. We wanted to provide an overview of current literature on RV involvement in HCM. Design. We performed a systematic search in PubMed and added additional articles by manual screening of references. The quality of the articles was assessed according to the GRADE system. Results. We identified 35 original articles on RV involvement in HCM. Based on these publications, RV hypertrophy occurs in 28-44% of HCM patients, depending on the cut-off value for hypertrophy and the method for assessment. Histological studies show the same structural changes in RV as are typically described in the LV cardiomyocyte hypertrophy and disarray, as well as fibrosis. These changes are similar, but less pronounced in the RV than in the LV. We discuss how HCM can impact the RV, either through a primary involvement similar to the LV or secondary to hemodynamic effects resulting from LV dysfunction. RV dysfunction in HCM is associated with higher mortality, partly due to an increased risk of ventricular tachycardia and sudden cardiac death. Conclusions. The evidence for RV involvement in HCM is limited. Multimodal imaging assessment of the RV should be included in the work-up of patients with HCM, and the added value of including RV function in the risk stratification algorithm should be further explored.

Right-ventricular mechanics assessed by cardiovascular magnetic resonance feature tracking in children with hypertrophic cardiomyopathy

Background

Although hypertrophic cardiomyopathy (HCM) is considered a disease of the left ventricle (LV), right ventricular (RV) abnormalities have also been reported on. Cardiovascular magnetic resonance feature tracking (CMR-FT) accurately and reproducibly quantifies RV myocardial deformation.

Aim

To investigate RV deformation disorders in childhood HCM using CMR-FT.

Material and methods

Consecutive subjects aged <18 years with echocardiographic evidence of HCM were enrolled. Cardiovascular magnetic resonance (CMR) was performed including RV volumetric and functional assessment, and late gadolinium enhancement (LGE) imaging.

Results

We included 54 children (37 males, 68.5%) with HCM, of which 28 patients (51.8%; mean extent of 2.18 ± 2.34% of LV mass) had late gadolinium enhancement. LV outflow tract obstruction (LVOTO) was detected in 19 subjects (35.2%). In patients with LVOTO, RV global longitudinal strain (RVGLS) (-16.1±5.0 vs. -20.7±5.3, p<0.01), RVGLS rate (-1.05±0.30 vs. -1.26±0.40, p = 0.03), RV radial strain (RVR) (15.8±7.7 vs. 22.1±7.0, p<0.01) and RVR rate (0.95±0.35 vs. 1.6±0.44, p<0.01) were lower than in patients without LVOTO. The RVR rate (p<0.01) was lower in patients with LGE in comparison to patients without LGE.

Conclusions

Children with HCM, especially with LVOTO, have significantly reduced indices of RV mechanics despite normal RV systolic function. It seems that the degree of LVOT obstruction is responsible for compromising the RV dynamics, rather than either mass or the amount of LV fibrosis.

Myocardial Mechanics Parameters That Predict Left Ventricular Outflow Tract Obstruction in Patients With Hypertrophic Cardiomyopathy: A Cardiovascular Magnetic Resonance Feature Tracking Analysis

OBJECTIVE

To identify left ventricular (LV) myocardial mechanics predictors of LV outflow tract obstruction (LVOTO) in patients with hypertrophic cardiomyopathy (HCM).

METHODS

Thirty-nine adults with HCM and 21 controls underwent cardiovascular magnetic resonance. The feature tracking (FT) analysis results of HCM patients with and without LVOTO and controls were compared.

RESULTS

Global radial strain measured on the short-axis slice (GRS-SAX) (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.02-1.15; P < 0.01), global longitudinal strain measured on the long-axis slice (GLS-LAX) (OR, 1.81; 95% CI, 1.21-2.73; P < 0.01) and GRS measured on the long-axis slice (GRS-LAX) (OR, 1.07; 95% CI, 1.01-1.13; P = 0.02) were independent predictors of LVOTO. The combination of GRS-SAX plus GLS-LAX and GRS-LAX showed great discriminatory power for identifying LVOTO with an area under the receiver operating characteristic curve value of 0.91 (95% CI: 0.81-1.00).

CONCLUSIONS

In adult HCM patients, GRS-SAX, GLS-LAX, and GRS-LAX were independent predictors of LVOTO. The combination of GRS-SAX plus GLS-LAX and GRS-LAX showed great discriminatory power for identifying LVOTO.

Left Ventricular Outflow Tract Obstruction in Hypertrophic Cardiomyopathy: The Utility of Myocardial Strain Based on Cardiac MR Tissue Tracking

BACKGROUND

Myocardial strain for assessment of hypertrophic cardiomyopathy (HCM) is of importance and may play a role in identifying obstruction in HCM patients.

PURPOSE

To evaluate the utility of myocardial strain for detecting left ventricular (LV) outflow tract (LVOT) obstruction in HCM patients based on magnetic resonance tissue tracking.

STUDY TYPE

Retrospective.

POPULATION

In all, 44 adult HCM patients with LVOT obstruction and 108 adult HCM patients without LVOT obstruction.

FIELD STRENGTH/SEQUENCE

1.5 T; Steady-state free-precession cine sequence; phase-sensitive inversion-prepared segmented gradient echo sequence for late gadolinium enhancement (LGE) imaging.

ASSESSMENT

Strain parameters including the local and global levels of LV myocardium and the subtraction (Sub) of myocardial strain variables between interventricular septal segments (IVSS) and noninterventricular septal segments (NIVSS) were measured for differentiating HCM with obstruction from nonobstruction. Average and maximum LV wall thickness (Average and Maximum LVWT) were also analyzed.

STATISTICAL TESTS

Univariate and multivariate logistic regression analysis, area under the receiver operating characteristic (ROC) curve (AUC), intraclass correlation coefficient.

RESULTS

In multivariate analysis, Average LVWT, Maximum LVWT, and the subtraction of radial peak strain (Sub Radial PS) between NIVSS and IVSS were independently associated with LVOT obstruction. The AUCs were 0.731, 0.840, and 0.890 for Average LVWT, Maximum LVWT, and Sub Radial PS, respectively. Sub Radial PS (cutoff value: 8.1%) demonstrated the highest sensitivity of 75.0% and a high specificity of 87.9% for identifying LVOT; Maximum LVWT (cutoff value: 22.9 mm) showed good sensitivity (72.7%) and specificity (83.3%). Combining Maximum LVWT >22.9 mm and Sub Radial PS > 8.1% achieved a better diagnostic performance (specificity 95.4%, sensitivity 70.5%).

DATA CONCLUSION

Combining Maximum LVWT >22.9 mm and Sub Radial PS >8.1% holds promise for objectively evaluating LVOT obstruction in HCM patients with very high specificity and acceptable sensitivity.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY STAGE: 2.

Right atrial function assessed by volume-derived values and speckle tracking echocardiography in patients with hypertrophic cardiomyopathy

Background

To detect the right atrial (RA) functions in hypertrophic cardiomyopathy (HCM) patients by using volume-derived values and two-dimensional strain.

Methods

Thirty-two HCM patients and 34 age and gender matched normal controls were enrolled for this study. RA volume-derived values were measured by using 2D ultrasonic images. RA strain (S-reservoir, S-conduit, S-booster pump) and strain rate (SR-reservoir, SR-conduit, SR-booster pump), representing the reservoir, conduit and booster pump functions, respectively, were measured by EchoPAC.

Results

Total RA emptying fraction (RAEF) and RA expansion index in HCM patients were significantly lower than normal controls (p < 0.05). The values of S-reservoir, S-conduit, Sr-reservoir and Sr-conduit in HCM patients were significantly lower than normal controls (p < 0.001). Although there were no significant differences in S-booster pump and Sr-booster pump between HCM patients and normal controls, the absolute values in HCM patients were lower than normal controls.

Conclusions

In this study, we concluded that RA dysfunctions, including the reservoir and conduit functions were impaired in HCM patients.

Advanced myocardial characterization in hypertrophic cardiomyopathy: feasibility of CMR-based feature tracking strain analysis in a case-control study

OBJECTIVES

This study aimed to evaluate the feasibility and reproducibility of using cardiovascular magnetic resonance feature tracking (CMR-FT) for analysis of bi-ventricular strain and strain rate (SR) in hypertrophic cardiomyopathy (HCM) patients as well as to explore the correlation between right ventricular (RV) and left ventricular (LV) deformation.

METHODS

A total of 60 HCM patients and 48 controls were studied. Global and segmental peak values of bi-ventricular longitudinal, circumferential, radial strain, and systolic SR were analyzed. Pearson analysis was performed to investigate the correlation of RV and LV deformation. Intra-observer and inter-observer reproducibility were also assessed.

RESULTS

LV mass in the HCM group was significantly higher than that in the control group. LV end-systolic and end-diastolic volume and RV end-systolic and end-diastolic volume in the HCM group were all significantly lower than the correlated parameters in the control group (p < 0.001, respectively), whereas no statistical difference was found in ejection fraction (p > 0.05). Global longitudinal strain (GLS), global longitudinal strain rate (GLSR), global circumferential strain (GCS), global circumferential strain rate (GCSR), global radial strain (GRS), and global radial strain rate (GRSR) of the LV and RV were all significantly lower than the control group, and segmental strain and SR were also true (p < 0.001, respectively). Bi-ventricular strain and SR measurements were highly reproducible at both intra- and inter-observer levels. Additionally, Pearson analysis showed RV GCS, GLS, and GRS positively correlated with LV GCS, GLS, and GRS (r = 0.713, p < 0.001; r = 0.728, p < 0.001; r = 0.730, p < 0.001, respectively).

CONCLUSIONS

CMR-FT is a promising approach to analyze impairment of global and segmental myocardium deformation in HCM patients non-invasively and quantitatively.

KEY POINTS

• CMR-FT allows for advanced myocardial characterization with high reproducibility. • As compared with controls, HCM patients have significant differences in CMR-FT strain analysis while ejection fraction was similar. • CMR-FT may serve as an early biomarker of HCM in subjects at risk.

Speckle tracking for predicting outcomes of balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension

BACKGROUND

Right ventricular (RV) function is a prognostic marker of chronic thromboembolic pulmonary hypertension (CTEPH). We used two-dimensional (2D) speckle-tracking echocardiography (STE) to evaluate the therapeutic effects of balloon pulmonary angioplasty (BPA) in CTEPH patients.

METHODS

A total of 46 CTEPH patients who underwent 2D STE before and after BPA were enrolled in this retrospective study. The following RV functional parameters were measured: tricuspid annular plane systolic excursion (TAPSE), right ventricular fractional area change (RVFAC), RV index of myocardial performance (RIMP), and free wall longitudinal strain (RVFWLS). Satisfactory BPA was defined as mean pulmonary arterial pressure (mPAP) <25 mm Hg or improvement in mPAP > 10 mm Hg after BPA. Patients were divided into two groups according to mPAP values: group I had satisfactory BPA outcomes; group Ⅱ had unsatisfactory BPA outcomes. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was used to determine the optimal cutoff values and the ability of RVFWLS to predict successful BPA outcomes.

RESULTS

After BPA, SPAP measured by echocardiography (SPAP_echo ) and RIMP decreased, but TAPSE, RVFAC, and RVFWLS increased. Before BPA, group Ⅰ had significantly better RV function than group Ⅱ. Multifactor logistic regression analysis identified RVFWLS as an independent factor associated with satisfactory BPA outcomes. The optimal cutoff value for RVFWLS in predicting satisfactory BPA outcomes was -12.2%.

CONCLUSIONS

Balloon pulmonary angioplasty improves RV function in CTEPH patients. RVFWLS is a valuable noninvasive tool with which to assess the treatment effects of BPA. CTEPH patients with lower RVFWLS may have limited benefit from BPA.

Higher ultrafiltration rate is associated with right ventricular mechanical dispersion

Objective:

Ultrafiltration rate is one of the major determinants of adverse outcomes in patients undergoing hemodialysis (HD) therapy. Previous studies have focused on the impact of HD on right ventricular (RV) peak strain values. However, the influence of HD on the temporal characteristics of deformation has not been reported yet. The aim of the present study was to evaluate the impact of high ultrafiltration rate (HUR) on RV mechanical dyssynchrony.

Methods:

Echocardiographic images focused on the RV and left ventricle (LV) were obtained from 60 patients (49.2±17.3 years, 22 female) before and after HD. Patients were divided into two groups according to ultrafiltration rate. Changes in echocardiographic parameters with HD were examined. Two-dimensional speckle-tracking strain analysis was used to assess deformation. Mechanical dispersion was measured as the standard deviation of time to peak longitudinal strain of six segments for RV and 18 segments for LV.

Results:

The average ultrafiltrated volume and ultrafiltration rate were 3000.1±1007.9 mL and 11.4±2.9 mL/kg/h, respectively. Global longitudinal strain (GLS) of the RV and LV decreased after HD in both groups. A significant difference was observed in RV mechanical dispersion with HD for patients in the high ultrafiltration group. A mild statistically insignificant increase in LV mechanical dispersion was also observed after HD.

Conclusion:

HUR has a substantial impact on LV and RV GLS and RV dyssynchrony. Ultrafiltration rates and volumes should be kept as low as possible to achieve hemodynamic stability and tolerability.

Left-ventricular mechanics in children with hypertrophic cardiomyopathy. CMR study

OBJECTIVES

To assess the magnitude of myocardial displacement abnormalities and their alterations with the fibrosis, left-ventricular (LV) outflow tract obstruction (LVOTO) and hypertrophy in juveniles with hypertrophic cardiomyopathy (HCM).

STUDY DESIGN

Fifty-five children [age 12,5±4.6years, 38 (69,1%) males, 19 (34,5%) with LVOTO] with HCM and 20 controls underwent cardiovascular magnetic resonance. The LV feature tracking (FT) derived strain and strain rates were quantified. Results of FT analysis were compared between HCM subjects and controls and between children with and without LVOTO.

RESULTS

Children with HCM exhibited decreased strain in both hypertrophied and nonhypertrophied segments versus controls. LV global longitudinal strain (LVGLS) rate (-0.69±0.04 vs -0.91±0.05, p=0,04), LV circumferential strain (LVCR) rate (-0.98±0.09 vs -1.27±0.06, p=0,02), LV radial strain (LVR) (18,5±1.9 vs 27,4±1.4, p<0,01) and LVR rate (0,98±0.1 vs 1,53±0.08, p<0,01) were substantially compromised in subjects with LVOTO vs without. In multivariable regression all LV myocardial dynamics markers, except for LVCR, exhibited a significant association with the degree of LVOTO. LVCR rate (β=0,31, p=0,02) and LVR (β=-0.24, p=0,04) were related to LV mass and only LVCR rate (β=0,15, p=0,03) was associated with the amount of LV fibrosis.

CONCLUSIONS

The reduction of all indices of LV myocardial mechanics in juvenile HCM patients was global but particularly pronounced in hypertrophied segments of the LV. The majority of the LV strains and strain rates were substantially compromised in subjects with LVOTO compared to patients without the obstruction. Myocardial mechanics indices seemed to be related to the degree of LVOTO rather than either to mass or the amount of fibrosis.

Echocardiographic Assessment of Right Ventricular Size and Function in Cats With Hypertrophic Cardiomyopathy

Background

Studies evaluating right ventricular (RV) structural and functional abnormalities in feline hypertrophic cardiomyopathy (HCM) are limited.

Hypothesis

Right ventricular structural and functional abnormalities are present in cats with HCM and are associated with clinical severity.

Animals

Eighty‐one client‐owned cats.

Methods

Retrospective 2‐dimensional (2D) echocardiographic study. Right atrial diameter (RAD), RV free wall thickness (RVFWd), RV internal dimension (RVIDd), RV fractional area change (FAC), and tricuspid annular plane systolic excursion (TAPSE) were measured in control cats (n = 26), cats with subclinical HCM (subclinical HCM; n = 31), and cats with HCM and congestive heart failure (HCM + CHF; n = 24).

Results

Right heart size (RAD, RVFWd, and RVIDd) and RV function (FAC and TAPSE) significantly (all P < .05) increased and decreased, respectively, in the HCM + CHF group compared with controls. In the subclinical HCM group, only RVFWd was significantly (P < .05) higher than in controls. Compared with reference intervals derived from controls, 29% of cats with HCM had increased RVFWd. Increased left ventricular free wall thickness, increased RVIDd and decreased TAPSE independently correlated with increased left atrial size. Cats with HCM and pleural effusion were significantly more likely to have increased RVFWd and had increased RAD and decreased TAPSE compared with cats without pleural effusion.

Conclusions and Clinical Importance

Right ventricular remodeling and dysfunction occur in some cats with HCM and may be associated with clinical severity. Our results support involvement of RV in the pathophysiology of HCM in some cats and support echocardiographic assessment of the RV in cats with HCM.

Nonalcoholic Steatohepatitis Score is an Independent Predictor of Right Ventricular Dysfunction in Patients with Nonalcoholic Fatty Liver Disease

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) is associated with increased risk of cardiovascular disease and impaired left ventricular (LV) function, yet the impact of NAFLD on right ventricular (RV) function remains unclear. We investigate the RV functional properties in patients with NAFLD.

METHODS

Ninety consecutive patients with the diagnosis of biopsy-proven NAFLD and 45 age- and sex-matched controls were included. All patients underwent an echocardiographic examination. RV function was evaluated by two-dimensional (2D) speckle-tracking echocardiography (STE).

RESULTS

Mean fibrosis stage and nonalcoholic steatohepatitis (NASH) scores were 1.3 ± 1.1 and 5.2 ± 1.6, respectively. NAFLD patients displayed decreased RV function compared to controls. NAFLD patients with liver fibrosis (67 patients) had significantly lower RV function assessed by GLS (global longitudinal strain) compared to patients without liver fibrosis (18.9 ± 3.4% vs. 21.6 ± 2.3%, P < 0.001). NASH score ≥5 was associated with lower RV-GLS (18.9 ± 3.1% vs. 21.0 ± 3.4%, P = 0.006). NASH score inversely correlated with RV-GLS (r = -0.370, P < 0.001) such as patients with impaired RV-GLS (<19%) showed significantly higher NASH score compared to normal RV-GLS group (5.8 ± 1.4 vs. 4.8 ± 1.7, P = 0.009). Logistic regression analysis revealed that NASH score was an independent predictor of impaired RV function in patients with NAFLD.

CONCLUSIONS

Patients with NAFLD have impaired RV function. NASH score inversely correlates with RV-GLS and independently predicts impaired RV function in patients with NAFLD.