Right heart size and function significantly correlate in patients with pulmonary arterial hypertension - a cross-sectional study.

BACKGROUND: The objective of this study was to assess, whether right atrial (RA) and ventricular (RV) size is related to RV pump function at rest and during exercise in patients with pulmonary arterial hypertension (PAH). METHODS: We included 54 patients with invasively diagnosed PAH that had been stable on targeted medication. All patients underwent clinical assessments including right heart catheterization and echocardiography at rest and during exercise. RV output reserve was defined as increase of cardiac index (CI) from rest to peak exercise (∆CIexercise). Patients were classified according to the median of RA and RV-area. RV pump function and further clinical parameters were compared between groups by student's t-test. Uni- and multivariate Pearson correlation analyses were performed. RESULTS: Patients with larger RA and/or RV-areas (above a median of 16 and 20cm2, respectively) showed significantly lower ∆CIexercise, higher mean pulmonary arterial pressure, pulmonary vascular resistance at rest and NT-proBNP levels. Furthermore, patients with higher RV-areas presented with a significantly lower RV stroke volume and pulmonary arterial compliance at peak exercise than patients with smaller RV-size. RV area was identified as the only independent predictor of RV output reserve. CONCLUSION: RV and RA areas represent valuable and easily accessible indicators of RV pump function at rest and during exercise. Cardiac output reserve should be considered as an important clinical parameter. Prospective studies are needed for further evaluation.

Cardiac MRI right ventricle / left ventricle (RV/LV) volume ratio improves detection of RV enlargement.

PURPOSE: To determine the normal range of the ratio of right ventricular (RV) end-diastolic volume to left ventricular (LV) end-diastolic volume by magnetic resonance imaging (MRI) and examine whether combining this volume ratio with RVEDV indexed to body surface area (RVEDVi) increased the detection of RV dilation in patients with pulmonary arterial hypertension (PAH). MATERIALS AND METHODS: MRI-derived ventricular function and volumes were measured in a control group (n = 152) and in patients with PAH (n = 46). Images were acquired with a 1.5T Siemens or a 1.5T Philips scanner using a steady-state free procession sequence. Proposed criteria for the detection of RV enlargement, including RVEDVi alone, RV/LV volume ratio alone, and combining both criteria, were evaluated in both groups. RESULTS: The range (mean ± 2 standard deviations) for the volume ratio in the normal population was found to be 0.906-1.266; there was no difference between genders (P = 0.70). Combining this ratio with RVEDVi detected RV enlargement in 21.7% (P < 0.001) PAH patients (volume ratio ≥1.27) who were not identified by the RVEDVi alone (>104 mL/m(2) for females and >113 mL/m(2) for males). CONCLUSION: Combining RV/LV volume ratio with indexed RVEDV increased detection of RV enlargement in a PAH population. This result may have potential impact in RV size assessment. J. Magn. Reson. Imaging 2016;43:1379-1385.

The effect of significant weight loss after bariatric surgery on echocardiographic indices: an observational study focusing on left ventricular deformation by 2D speckle echocardiography and right ventricular size.

BACKGROUND: Obesity is a known risk factor for atherosclerosis and cardiac disease. HYPOTHESIS: This study evaluated the effect of significant weight loss following bariatric surgery on myocardial deformation indices and right ventricular size (RV). This was a prospective cohort study. Morbid obese patients scheduled for bariatric surgery from July 2017 to February 2018 at Firoozgar Hospital were included in our study and referred for transthoracic echocardiography at Rajaie Cardiovascular Medical and Research Center. RESULTS: Thirty-four patients entered the study. The absolute value of global longitudinal strain (GLS) at baseline, 3, and 6 months after surgery was 17.42 ± 2.94%, 18.24 ± 3.09%, and 19.52 ± 2.78%, respectively, with a statistically significant difference from baseline to after six months (P value < 0.001). The absolute value of global circumferential strain (GCS) at baseline, 3, and 6 months after surgery was 20.14 ± 4.22%, 23.32 ± 4.66%, and 24.53 ± 4.52%, respectively, with statistically significant changes (P value < 0.001) from baseline to three months and from baseline to six months and no significant difference from three months to six months. A significant decrease was reported in mechanical dispersion of circumferential strain (38.05 ± 23.81-23.37 ± 20.86 ms, P value = 0.006) 6 months after surgery. Right ventricular size three- and six-month post-surgery showed a significant decrease relative to baseline echocardiography. CONCLUSIONS: Bariatric surgery could enhance cardiac function, as proven by 2D speckle echocardiography. Changes in RV size may be related to weight loss and should be considered when assessing patients who have undergone bariatric surgery.

Right ventricular global dysfunction score: a new concept of right ventricular function assessment in patients with heart failure with reduced ejection fraction (HFrEF).

Background: Right ventricular (RV) function is currently being evaluated solely according to the properties of RV myocardium. We have tested a concept that in patients with heart failure with reduced ejection fraction (HFrEF), RV assessment should integrate the information about both RV function as well as size. Methods: A total of 836 stable patients with HFrEF (LVEF 23.6 ± 5.8%, 82.8% males, 68% NYHA III/IV) underwent echocardiographic evaluation and were prospectively followed for a median of 3.07 (IQRs 1.11; 4.89) years for the occurrence of death, urgent heart transplantation or implantation of mechanical circulatory support. Results: RV size (measured as RV-basal diameter, RVD1) was significantly associated with an adverse outcome independent of RV dysfunction grade (p = 0.0002). The prognostic power of RVD1 was further improved by indexing to body surface area (RVD1i, p < 0.05 compared to non-indexed value). A novel parameter named RV global dysfunction score (RVGDs) was calculated as a product of RVD1i and the degree of RV dysfunction (1-4 for preserved RV function, mild, moderate and severe dysfunction, respectively). RVGDs showed a superior prognostic role compared to RV dysfunction grade alone (ΔAUC >0.03, p < 0.0001). In every subgroup of RVGDs (<20, 20-40, 40-60, >60), patients with milder degree of RV dysfunction but more dilated RV had similar outcome as those with more severe degree of RV dysfunction but smaller RV size (all p > 0.50), independent of tricuspid regurgitation severity and degree of pulmonary hypertension. Conclusion: RV dilatation is a manifestation of RV dysfunction. The evaluation of RV performance should integrate the information about both RV size and function.

Two-Dimensional Echocardiographic Right Ventricular Size and Systolic Function Measurements Stratified by Sex, Age, and Ethnicity: Results of the World Alliance of Societies of Echocardiography Study.

BACKGROUND: Echocardiographic assessment of right ventricular (RV) systolic function is an important component of clinical decision making. Although professional societies have worked to define normal ranges of RV size and function, their guidelines have not included the impacts of age, sex, and ethnicity on these parameters, as they have for the left ventricle. The World Alliance of Societies of Echocardiography study was designed to investigate the effects of age, sex, and ethnicity on all cardiac chambers. The aim of this study was to explore whether these differences exist for RV systolic parameters. METHODS: Adequate two-dimensional RV-focused views for the measurement of systolic parameters, including fractional area change and global and free wall longitudinal strain, were available in 1,913 subjects (mean age, 47 ± 17 years; 51% men). Basal and mid-RV dimensions, length, tricuspid annular peak systolic excursion, tissue Doppler S' velocity, and myocardial performance index were also measured. Subjects were grouped by age (<40, 41-65, and >65 years), with results also stratified by sex and ethnicity (Asian, black, or white) and analyzed using vendor-independent software. Differences among groups were evaluated using analysis of variance. RESULTS: Women had smaller absolute and indexed RV areas and absolute RV dimensions and higher magnitudes of fractional area change, free wall strain, and global longitudinal strain compared to men. With respect to age, most of the statistically significant differences were noted between the <40- and >65-year age groups, with RV areas and lengths smaller in older age groups and RV functional parameters (S', fractional area change, tricuspid annular plane systolic excursion, global longitudinal strain, free wall strain, and myocardial performance index) showing minimal decreases or no changes with age. Although there were no meaningful differences in functional parameters among ethnic groups, RV size was smallest in Asians. CONCLUSIONS: These findings suggest that although two-dimensional RV parameters are age and sex dependent, association with race is less apparent, excepting that the Asian population appears to have smaller chamber sizes compared with whites and blacks.

Comparison Between Four-Chamber and Right Ventricular-Focused Views for the Quantitative Evaluation of Right Ventricular Size and Function.

BACKGROUND: Right ventricular (RV) function plays a pivotal prognostic role in multiple cardiac diseases. Echocardiography guidelines recommend that RV quantification be performed in the RV-focused view, which is theoretically more reproducible than the four-chamber (4Ch) view. However, differences between views in RV size and function measurements have never been systematically studied. Accordingly, the aim of this study was to compare (1) RV size and function parameters obtained from the RV-focused and 4Ch views and (2) test-retest variability between these two views. METHODS: Fifty patients (26 men; mean age, 63 ± 18 years) undergoing clinically indicated transthoracic echocardiography were prospectively enrolled. Each patient underwent three repeated acquisitions of the 4Ch and RV-focused views by two sonographers. The first operator performed two acquisitions at the beginning and the end of the clinical transthoracic echocardiographic study, and the second operator performed the third acquisition afterward. RV size and function measurements were obtained from the two views and compared using paired t-test analysis and Bland-Altman analysis. Intra- and interoperator test-retest and intra- and interreader variability for both views were assessed using intraclass correlations and coefficients of variation. RESULTS: All RV size parameters were significantly larger when measured in the RV-focused view compared with the 4Ch view. Also, all RV function parameters, including RV free wall and global longitudinal strain, were larger in magnitude when measured in the RV-focused view. Measurements variability was consistently better for the RV-focused view. CONCLUSIONS: RV size and function measurements obtained from the RV-focused and 4Ch views are not interchangeable. RV size and function parameters measured from the RV-focused view are more reproducible than from 4Ch acquisitions. Therefore, only the RV-focused view should be used for quantitative assessment of the right ventricle.

Right ventricular basal inflow and outflow tract diameters overestimate right ventricular size in subjects with sigmoid-shaped interventricular septum: a study using three-dimensional echocardiography.

Sigmoid-shaped ventricular septum (SS), a frequently encountered minor abnormality in echocardiographic examinations of the elderly, may have some influence on RV shape. We aimed to determine the influence of SS on the accuracy of the 6 RV linear diameter measurements in the light of three-dimensional echocardiographic (3DE) RV volume. The aorto-septal angle (ASA) was measured in the parasternal long-axis view using two-dimensional echocardiography (2DE) as an index of SS in 70 patients without major cardiac abnormalities who were subdivided into 35 with SS (ASA ≤ 120°) and 35 without SS (NSS). We measured RV end-diastolic volume (RVEDV) using 3DE; in addition, using 2DE, we measured basal RV diameter, mid-cavity diameter, longitudinal diameter and end-diastolic area in the apical four-chamber view; proximal RV outflow tract (RVOT) diameter in the parasternal long-axis view; and proximal and distal RVOT diameters in the parasternal short-axis view. RVEDV did not differ between the SS and NSS groups. The SS group had greater basal RV diameter and proximal and distal RVOT diameters than the NSS group. RV mid-cavity diameter, longitudinal diameter, and end-diastolic area did not differ between the groups. Among the 2DE parameters of RV size, RV end-diastolic area was most strongly correlated with RVEDV (r = 0.67), followed by RV mid-cavity diameter (r = 0.58). When SS is present, the echocardiographic basal RV diameter and RVOT diameters overestimate RV size, and the measurement of RV end-diastolic area and mid-cavity diameter more correctly reflect 3D RV volume.

Echocardiographic evaluation of the right ventricular dimension and systolic function in dogs with pulmonary hypertension.

BACKGROUND: Right ventricular (RV) enlargement and dysfunction are associated with prognosis in humans with pulmonary hypertension (PH). HYPOTHESIS/OBJECTIVES: To assess RV size and systolic function in dogs with PH and to determine if they are associated with disease severity and right-sided congestive heart failure (R-CHF). ANIMALS: 89 dogs with PH and 74 healthy dogs. METHODS: Prospective observational study. PH was classified according to the tricuspid regurgitation pressure gradient. RV end-diastolic area (RVEDA) index was calculated as RVEDA divided by body surface area. RV systolic function was assessed with the tricuspid annular plane systolic excursion (TAPSE) and the RV fractional area change (FAC) normalized for body weight (TAPSEn and FACn, respectively). RESULTS: RVEDA index was higher in dogs with moderate PH (10.8 cm2 /m2 ; range, 6.2-14.4 cm2 /m2 ) and severe PH (12.4 cm2 /m2 ; range, 7.7-21.4 cm2 /m2 ) than in those with mild PH (8.4 cm2 /m2 ; range, 4.8-11.6 cm2 /m2 ) and control dogs (8.5 cm2 /m2 ; range, 2.8-11.6 cm2 /m2 ; P < .001). RVEDA index was significantly higher in dogs with R-CHF (13.7 cm2 /m2 ; range, 11.0-21.4 cm2 /m2 ) than in dogs without R-CHF (9.4 cm2 /m2 ; range, 4.8-17.1 cm2 /m2 ; P < .001). The severity of tricuspid regurgitation (TR) was the only independent predictor of the RVEDA index (P < .001). TAPSEn and FACn were not significantly different among varying degrees of PH severity and between dogs with and without R-CHF. CONCLUSIONS AND CLINICAL IMPORTANCE: The RVEDA index can be used to evaluate RV size in dogs. It can provide additional information in dogs with PH and predict R-CHF. Severity of TR is the main determinant of RV enlargement in dogs with PH.

Response of right ventricular size to treatment with cardiac resynchronization therapy and the risk of ventricular tachyarrhythmias in MADIT-CRT.

BACKGROUND: Cardiac resynchronization therapy (CRT) is increasingly recognized for its ability to reduce ventricular tachyarrhythmias, possibly associated with left ventricular reverse remodeling, but the role of the right ventricle (RV) in this process has not been examined. OBJECTIVE: The purpose of this study was to investigate the relationship between ventricular tachyarrhythmias and change in RV dimensions in patients receiving CRT with a defibrillator (CRT-D). METHODS: Multivariate Cox proportional hazards regression modeling was used to assess the risk for fast (≥180 bpm) ventricular tachycardia/ventricular fibrillation (VT/VF) or death by baseline and follow-up RV size (defined as right ventricular end-diastolic area [RVEDA]) among 1495 patients enrolled in the Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy (MADIT-CRT). RESULTS: Multivariate analysis showed that treatment with CRT-D was independently associated with a 27% (P = .003) reduction in the risk of VT/VF or death among patients with larger RVs (>first quartile RVEDA ≥13 mm(2)/m(2)) compared with implantable cardioverter-defibrillator (ICD)-only therapy, whereas in patients with smaller RVs there was no significant difference in the risk of VT/VF between the 2 treatment arms (hazard ratio = 1.00, P = .99). At 1-year follow-up, CRT-D patients displayed significantly greater reductions in RVEDA compared to ICD-only patients (P <.001), associated with a corresponding reduction in the risk of subsequent VT/VF or death (>first quartile reduction in RVEDA with CRT-D vs ICD-only: hazard ratio = 0.55, P <.001) independent of changes in left ventricular dimensions. CONCLUSION: Our findings suggest that the RV may have an important role in determining the antiarrhythmic effect of CRT independent of the effect of the device on the left ventricle.