Correlation between right ventricular T<Subscript>1</Subscript> mapping and right ventricular dysfunction in non-ischemic cardiomyopathy

Right ventricular (RV) fibrosis is increasingly recognized as the underlying pathological substrate in a variety of clinical conditions. We sought to employ cardiac magnetic resonance (CMR) techniques of strain imaging and longitudinal relaxation time (T₁) mapping to better examine the relationship between RV function and structure. Our aim was to initially evaluate the feasibility of these techniques to evaluate the right ventricle. We then sought to explore the relationship between RV function and underlying fibrosis, along with examining the evolution of RV remodeling according to the amount of baseline fibrosis. Echocardiography was performed in 102 subjects with non-ischemic cardiomyopathy. Right ventricular parameters were assessed including: fractional area change (FAC) and longitudinal strain. The same cohort underwent CMR. Post-contrast T₁ mapping was performed as a marker of fibrosis with a Look-Locker technique using inversion recovery imaging. Mid-ventricular post-contrast T₁ values of the RV free wall, RV septum and lateral LV were calculated using prototype analysis software. Biventricular volumetric data including ejection fraction was measured by CMR using a cine short axis stack. CMR strain analysis was also performed to assess 2D RV longitudinal and radial strain. Simultaneous biochemical and anthropometric data were recorded. Subjects were followed over a median time of 29 months (IQR 20–37 months) with echocardiography to evaluate temporal change in RV FAC according to baseline post-contrast T₁ values. Longitudinal data analysis was performed to adjust for patient loss during follow-up. Subjects (62% men, 51?±?15 years) had mild to moderately impaired global RV systolic function (RVEF?=?39?±?15%; RVEDV?=?187?±?69 ml; RVESV?=?119?±?68 ml) and moderate left ventricular dysfunction at baseline (LVEF 30?±?17%). Good correlation was observed between mean LV and RV post-contrast T₁ values (r?=?0.652, p?<?0.001), with similar post-contrast T₁ values maintained in both the RV free wall and septum (r?=?0.761, p?<?0.001). CMR RVEF demonstrated a proportional correlation with echocardiographic measures of RV longitudinal function and CMR RV strain (longitudinal r?=??0.449, p?=?0.001; radial r?=??0.549, p?<?0.001). RVEF was related to RV post-contrast T₁ values, particularly in those with RV dysfunction (free wall T₁ r?=?0.259 p?=?0.027; septal T₁ r?=?0.421 p?<?0.001). RV strain was also related to RV post-contrast T₁ values (r?=??0.417, p?=?0.002). Linear regression analysis demonstrated strain and post-contrast T1 values to be independently associated with RVEF. Subjects with severe RV dysfunction (CMR RVEF <25%) demonstrated lower RV CMR strain (longitudinal p?=?0.018; radial p?<?0.001), RV T₁ values (free wall p?=?0.013; septum <0.001) and RV longitudinal echocardiography parameters despite no difference in afterload. During follow-up, those with RV free wall post-contrast T₁ values?≥?350 ms demonstrated ongoing improvement in FAC (Δ6%), whilst values <350 ms were associated with deterioration in RV function (ΔFAC?=??5%) (p?=?0.026). CMR provides a comprehensive method by which to evaluate right ventricular function. Post-contrast T₁ mapping and CMR strain imaging are technically feasible and provide incremental information regarding global RV function and structure. The proportional relationship between RV function and post-contrast T₁ values supports that myocardial fibrosis is a causative factor of RV dysfunction in NICM, irrespective of RV afterload. This same structural milieu also appears integral to the propensity for both positive and negative RV remodeling long-term, suggestive that this is also determined by the degree of underlying RV fibrosis.     

Relationship between cardiovascular risk factors and myocardial strain values of both ventricles in asymptomatic Asian subjects: measurement using cardiovascular magnetic resonance tissue tracking

The purpose of this study was to evaluate the association between myocardial deformation parameters and cardiovascular risk factors in asymptomatic Asian subjects and to provide reproducibility for deformation parameters of both ventricles using cardiovascular magnetic resonance (CMR) tissue tracking (TT). We enrolled 129 asymptomatic healthy adults who underwent CMR and assessed the cardiovascular risk factors in all individuals. All subjects had normal left ventricular systolic function. Commercial software was used to derive myocardial deformation parameters of both ventricles from short-axis cine images and long-axis cine images with two-, three-, and four-chamber views. Linear regression analysis was performed for evaluation of the association with all strain parameters for each age and systolic blood pressure. Intra class correlation was also calculated in CMR-TT to determine interobserver variability. In all 129 patients, the strain values for the left ventricle (LV) were 48.90?±?9.05 for radial strain (RS, %), ??22.30?±?2.33 for circumferential strain (CS, %), and ??19.76?±?2.22 for longitudinal strain (LS, %). The strain values for the right ventricle (RV) were 18.63?±?6.52 for RS, ??10.60?±?3.33 for CS, and ??25.06?±?3.01 for LS. In all 129 patients (male, n?=?105), all strain parameters of LV and RV was significantly different among males and females (all p values?<?0.05). The LV strain parameters were significantly associated with age by univariate linear regression analysis: RS, beta?=?0.219, p?=?0.002; CS, beta?=???0.668, p?=?0.014 (except for LS, beta?=???0.104, p?=?0.720). With regard to hypertension, diabetes mellitus and dyslipidemia, the values of all strain parameters in both ventricles were not significantly different between individuals with or without risk factors. Inter-observer agreement for three strain variables of LV and RV was 0.915 and 0.715 by iota index, and intra-observer agreement of LV and RV was 0.955 and 0.959 by iota index. The strain parameters by CMR-TT showed an association with age and significant difference in gender, on the other hands, not significantly different between with or without of the other conventional cardiovascular risk factors. The reproducibility of three LV strain parameters was higher than that of the respective RV strain parameters.     

The ventricular residence time distribution derived from 4D flow particle tracing: a novel marker of myocardial dysfunction

4D flow cardiac magnetic resonance (CMR) imaging allows visualisation of blood flow in the cardiac chambers and great vessels. Post processing of the flow data allows determination of the residence time distribution (RTD), a novel means of assessing ventricular function, potentially providing additional information beyond ejection fraction. We evaluated the RTD measurement of efficiency of left and right ventricular (LV and RV) blood flow. 16 volunteers and 16 patients with systolic dysfunction (LVEF?<?50%) underwent CMR studies including 4D flow. The RTDs were created computationally by seeding virtual ‘particles’ at the inlet plane in customised post-processing software, moving these particles with the measured blood velocity, recording and counting how many exited per unit of time. The efficiency of ventricular flow was determined from the RTDs based on the time constant (RTDc?=???1/B) of the exponential decay. The RTDc was compared to ejection fraction, T1 mapping and global longitudinal strain (GLS). There was a significant difference between groups in LV RTDc (healthy volunteers 1.2?±?0.13 vs systolic dysfunction 2.2?±?0.80, p?<?0.001, C-statistic?=?1.0) and RV RTDc (1.5?±?0.15 vs 2.0?±?0.57, p?=?0.013, C-statistic?=?0.799). The LV RTDc correlated significantly with LVEF (R?=???0.84, P?<?0.001) and the RV RTDc had significant correlation with RVEF (R?=???0.402, p?=?0.008). The correlation between LV RTDc and LVEF was similar to GLS and LVEF (0.926, p?<?0.001). The ventricular residence time correlates with ejection fraction and can distinguish normal from abnormal systolic function. Further assessment of this method of assessment of chamber function is warranted.     

Cardiac structure and function in elite Native Hawaiian and Pacific Islander Rugby Football League athletes: an exploratory study

The aim of this exploratory study was to define the Athletes Heart (AH) phenotype in Native Hawaiian & Pacific Islander (NH&PI) Rugby Football League (RFL) athletes. Specifically, (1) to describe conventional echocardiographic indices of left ventricle (LV) and right ventricle (RV) structure and function in NH&PI RFL players and matched RFL Caucasian controls (CC) and (2) to demonstrate LV and RV mechanics in these populations. Ethnicity is a contributory factor to the phenotypical expression of the AH. There are no data describing the cardiac phenotype in NH&PI athletes. Twenty-one male elite NH&PI RFL athletes were evaluated using conventional echocardiography and myocardial speckle tracking, allowing the assessment of global longitudinal strain (ε) and strain rate (SR); and basal, mid and global radial and circumferential ε and SR. Basal and apical rotation and twist were also assessed. Results were compared with age-matched Caucasian counterparts (CC; n?=?21). LV mass [42?±?9 versus 37?±?4 g/(m^2.7)], mean LV wall thickness (MWT: 9.5?±?0.7 and 8.7?±?0.4 mm), relative wall thickness (RWT: 0.35?±?0.04 and 0.31?±?0.03) and RV wall thickness (5?±?1 and 4?±?1 mm, all p?<?0.05) were greater in NH&PI compared with CC. LV and RV cavity dimensions and standard indices of LV and RV systolic and diastolic function were similar between groups. NH&PI demonstrated reduced peak LV mid circumferential ε and early diastolic SR, as well as reduced global radial ε. There was reduced basal rotation at 25–35% systole, reduced apical rotation at 25–40% and 60–100% systole and reduced twist at 85–95% systole in NH&PI athletes. There were no differences between the two groups in RV wall mechanics. When compared to Caucasian controls, NH&PI rugby players have a greater LV mass, MWT and RWT with concomitant reductions in circumferential and twist mechanics. This data acts to prompt further research in NH&PI athletes.     

Right ventricular relative wall thickness as a predictor of outcomes and of right ventricular reverse remodeling for patients with pulmonary hypertension

Mid-term right ventricular (RV) reverse remodeling after treatment in patients with pulmonary hypertension (PH) is associated with long-term outcome as well as baseline RV remodeling. However, baseline factors influencing mid-term RV reverse remodeling after treatment and its prognostic capability remain unclear. We studied 54 PH patients. Mid-term RV remodeling was assessed in terms of the RV area, which was traced planimetrically at the end-systole (RVESA). RV reverse remodeling was defined as a relative decrease in the RVESA of at least 15% at 10.2?±?9.4 months after treatment. Long-term follow-up was 5 years. Adverse events occurred in ten patients (19%) and mid-term RV reverse remodeling after treatment was observed in 37 (69%). Patients with mid-term RV reverse remodeling had more favorable long-term outcomes than those without (log-rank: p?=?0.01). Multivariate logistic regression analysis showed that RV relative wall thickness (RV-RWT), as calculated as RV free-wall thickness/RV basal linear dimension at end-diastole, was an independent predictor of mid-term RV reverse remodeling (OR 1.334; 95% CI, 1.039–1.713; p?=?0.03). Moreover, patients with RV-RWT ≥0.21 showed better long-term outcomes than did those without (log-rank p?=?0.03), while those with RV-RWT ≥0.21 and mid-term RV reverse remodeling had the best long-term outcomes. Patients with RV-RWT <0.21 and without mid-term RV reverse remodeling, on the other hand, had worse long-term outcomes than other sub-groups. In conclusions, RV-RWT could predict mid-term RV reverse remodeling after treatment in PH patients, and was associated with long-term outcomes. Our finding may have clinical implications for better management of PH patients.     

Value of three-dimensional strain parameters for predicting left ventricular remodeling after ST-elevation myocardial infarction

This study was to evaluate the value of multi-directional strain parameters derived from three-dimensional (3D) speckle tracking echocardiography (STE) for predicting left ventricular (LV) remodeling after ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI) compared with that of two-dimensional (2D) global longitudinal strain (GLS). A total of 110 patients (mean age, 54?±?9 years) after STEMI treated with primary PCI were enrolled in our study. At baseline (within 24 h after PCI), standard 2D echocardiography, 2D STE and 3D STE were performed to acquire the conventional echocardiographic parameters and strain parameters. At 3-month follow-up, standard 2D echocardiography was repeated to all the patients to determine LV remodeling, which was defined as a 20% increase in LV end-diastolic volume. At 3-month follow-up, LV remodeling occurred in 26 patients (24%). Compared with patients without LV remodeling, patients with remodeling had significantly reduced 2D GLS (?12.5?±?3.2% vs ?15.0?±?3.1%, p?<?0.001), 3D GLS (?9.9?±?2.2% vs ?13.1?±?2.7%, p?<?0.001), 3D global area strain (GAS) (?20.3?±?3.9% vs ?23.3?±?4.8%, p?=?0.005) and 3D global radial strain (GRS) (29.0?±?7.4% vs 34.3?±?8.5%, p?=?0.007) at baseline, but there is no significant difference in 3D global circumferential strain (GCS) (?12.7?±?2.9% vs ?13.0?±?3.2%, p?=?0.822). Separated multivariate analysis shows that 2D GLS, 3D GLS, 3D GAS and 3D GRS all can be independent predictors of LV remodeling. However, receiver-operating characteristic curve analysis showed that the area under the curve of 3D GLS (0.82) for predicting LV remodeling was significantly higher than that of 2D GLS (0.72, p?=?0.034), 3D GAS (0.68, p?<?0.001) and 3D GRS (0.68, p?<?0.001). In patients after STEMI, 2D GLS, 3D GLS, 3D GAS and 3D GRS but not 3D GCS measured after primary PCI are independent predictors of LV remodeling and 3D GLS is the most powerful predictor among them.     

Left ventricular reverse remodeling in dilated cardiomyopathy- maintained subclinical myocardial systolic and diastolic dysfunction

In idiopathic dilated cardiomyopathy (DCM), myocardial deformational parameters and their relationships remain incompletely characterized. We measured those parameters in patients with DCM, during left ventricular reverse remodeling (LVRR). Prospective study of 50 DCM patients (in sinus rhythm), with left ventricular ejection fraction (EF) <40%. LVRR was defined as an increase of ten units of EF and decrease of diastolic left ventricular diameter (LVDD) in the absence of resynchronization therapy. Performed morphological analysis, myocardial performance quantification (LV and RV Tei indexes) and LV averaged peak systolic longitudinal strain (SSR long) and circumferential strain (SSR circ). At baseline, mean EF was 25.4?±?9.8%, LVDD was 62.4?±?7.4 mm, LVDD/BSA of 34.2?±?4.5 mm/m² and 34% had MR grade >II/IV. LVRR occurred in 34% of patients within 17.6?±?15.6 months and was associated with a reduced rate of death or heart failure hospitalization (5.9% vs. 33.3; p?=?0.03). Patients with LVRR had a final EF of 48.9?±?7.9% (Δ LV EF of 22.4%) and there was a significant decrease (p?<?0.05) in: LVDD/BSA, LV systolic diameter/BSA, LV diastolic volume, LV systolic volume, LV mass; an increase (p?<?0.05) in sphericity index. However, measures of diastolic function (LA volume/BSA, e′velocity and’ E/e′ratio), final LV and RV Tei indexes were not significantly different from baseline. Additionally, final SSR circ and SSR long values were not different from basal. Patients who recovered EF >50% (n?=?10), SSR circ and SSR long were inferior to normal. Improvement in EF occurred in one-third of DCM pts and was associated with a decrease of major cardiac events. There was an improvement of diastolic and systolic volumes and in sphericity index, confirming truly LV reverse reshaping. However, myocardial performance indexes, SSR long and SSR circ in reverse-remodeled DCM were still abnormal, suggesting a maintained myocardial systolic and diastolic dysfunction.     

Right ventricular function and mechanics in chemotherapy- and radiotherapy-naïve cancer patients

The present research evaluated right ventricular (RV) structure, function and mechanics in the cancer patients before initiation of chemo- or radiotherapy, and the association between cancer and decreased RV longitudinal strain. This retrospective investigation included 101 chemo- and radiotherapy-naïve patients with solid cancer and 38 age- and gender-matched controls with similar cardiovascular risk profile. Echocardiographic examination and strain evaluation was performed in all participants. RV structure and RV systolic and diastolic function estimated with conventional echocardiographic parameters were similar between the cancer patients and controls. However, RV global longitudinal strain (??22.7?±?2.6% vs. ??21.1?±?2.4%, p?<?0.001) was significantly decreased in the cancer patients than in controls. The same was revealed for RV free wall endocardial (??33.6?±?4.3% vs. ??31.4?±?4.0%, p?=?0.006) and mid-myocardial (??25.2?±?3.6% vs. ??23.7?±?3.8%, p?=?0.035) longitudinal RV strains, whereas difference was not found in RV free wall epicardial longitudinal strain. The presence of cancer was independently of age, gender, body mass index, left ventricular hypertrophy, diabetes, hypertension and pulmonary pressure associated with reduced RV global longitudinal strain (OR 3.79; 95% CI 2.18–10.92, p?<?0.001), as well as with decreased free wall RV longitudinal strain (OR 5.73; 95% CI 3.17–9.85, p?<?0.001). RV strain is deteriorated in the chemo- and radiotherapy-naïve cancer patients. Endocardial and mid-myocardial layers are more affected than epicardial strain in the cancer patients. The presence of cancer is independently of other clinical parameters associated with reduced RV longitudinal strain.     

Regional contribution to ventricular stroke volume is affected on the left side,but not on the right in patients with pulmonary hypertension

To develop more sensitive measures of impaired cardiac function in patients with pulmonary hypertension (PH), since detection of impaired right ventricular (RV) function is important in these patients. With the hypothesis that a change in septal function in patients with PH is associated with altered longitudinal and lateral function of both ventricles, as a compensatory mechanism, we quantified the contributions of these parameters to stroke volume (SV) in both ventricles using cardiac magnetic resonance (CMR). Seventeen patients (10 females) evaluated for PH underwent right heart catheterization (RHC) and CMR. CMR from 33 healthy adults (13 females) were used as controls. Left ventricular (LV) atrioventricular plane displacement (AVPD) and corresponding longitudinal contribution to LVSV was lower in patients (10.8?±?3.2 mm and 51?±?12?%) compared to controls (16.6?±?1.9 mm and 59?±?9?%, p?<?0.0001 and p?<?0.01, respectively). This decrease did not differ in patient with ejection fraction (EF) >50?% and <50?% (p?=?0.5) and was compensated for by increased LV lateral contribution to LVSV in patients (49?±?13?% vs. 37?±?7?%, p?=?0.001). Septal motion contributed less to LVSV in patients (5?±?8?%) compared to controls (8?±?4?%, p?=?0.05). RV AVPD was lower in patients (12.0?±?3.6 mm vs. 21.8?±?2.2 mm, p?<?0.0001) but longitudinal and lateral contribution to RVSV did not differ between patients (78?±?17?% and 29?±?16?%) and controls (79?±?9?% and 31?±?6?% p?=?0.7 for both) explained by increased RV cross sectional area in patients. LV function is affected in patients with PH despite preserved global LV function. The decreased longitudinal contribution and increased lateral contribution to LVSV was not seen in the RV, contrary to previous findings in patients with volume loaded RVs.     

The effect of different treatment strategies on left ventricular myocardial deformation parameters in patients with chronic renal failure

The aim of this study was to compare left ventricular (LV) functions by speckle tracking echocardiography (STE) in chronic kidney disease (CKD) patients in various stages and under different renal replacement treatments in order to evaluate possible differences between them. This prospective study included 150 patients with CKD. Renal transplantation patients with glomerular filtration rate greater than 60 ml/min/1.73 m², patients receiving hemodialysis three times a week, and patients in the predialysis stage with glomerular filtration rate less than 30 ml/dk/1.73 m² were assigned into Group 1 (n?=?50), Group 2 (n?=?50), and Group 3 (n?=?50), respectively. LV longitudinal, circumferential, and radial myocardial deformation parameters (strain, strain rate [SR], rotation, twist) were evaluated by STE. Peak systolic longitudinal strain was higher in the transplantation group than the hemodialysis group (??19.93?±?3.50 vs???17.47?±?3.28%, p?<?0.017). Peak systolic circumferential strain was lower in the hemodialysis group (??20.97?±?4.90%) than Groups 1 and 3 (??25.87?±?4.20 and ??24.74?±?4.55%, respectively, p?<?0.001). Peak systolic radial SR was higher in the transplantation group than the hemodialysis group (1.84?±?0.52 vs 1.55?±?0.52 s^?1, respectively, p?<?0.017). Other longitudinal and circumferential deformation parameters together with peak early diastolic radial SR and twist were also significantly different between the groups. Strain, SR, and twist values were mostly lower in the hemodialysis patients, but generally higher in the transplantation patients. LV functions evaluated by STE are better in the renal transplantation patients than the hemodialysis patients and than those in the predialysis stage. This may indicate beneficial effects of renal transplantation on cardiac functions.     

Echocardiographic assessment of regional right ventricular systolic function using two-dimensional strain echocardiography and evaluation of the predictive ability of longitudinal 2D-strain imaging for pulmonary arterial hypertension in systemic sclerosis patients

Systemic sclerosis (SSc) is a generalized connective tissue disorder, and SSc patients are at risk of developing pulmonary arterial hypertension (PAH). The aims of this study are to evaluate the right ventricular regional systolic function using two-dimensional speckle-tracking echocardiography (2D STE) and to determine the predictive ability of peak longitudinal systolic strain (PLSS) at the RV lateral wall for PAH in SSc patients. 80 SSc patients (mean age 51?±?12 years) were included in the study. Echocardiography and 2D STE were performed at baseline and after 12 months. RHC was performed only in SSc patients with clinical indications. PLSS at the apical segment of the RV free wall was significantly impaired in PAH patients compared with non-PH patients (–14.6?±?5.9 vs. ??22.2?±?7.5%, p?=?0.034). PLSS at the basal, mid, and apical segments of the RV free wall was lower in both groups at follow-up compared to baseline, but the drop in strain values was statistically significant only in the non-PH group (p?<?0.05). Right atrial area (OR 1.758; p?=?0.023), peak tricuspid regurgitation velocity (OR 24.23; p?=?0.011) and PLSS at the apical segment of the RV lateral wall (OR 2.47; p?=?0.005) were independent predictors of PAH. A cut-off value of ??14.48% PLSS at the apical segment of the RV lateral wall resulted in 100% specificity for predicting PAH in SSc patients. RV pressure overload affects RV systolic function as manifested by impaired RV longitudinal deformation. Evaluating RV regional systolic function with 2D STE could be useful as an additional echocardiographic parameter for screening PAH in SSc patients.     

Left and right ventricular longitudinal strain-volume/area relationships in elite athletes

We propose a novel ultrasound approach with the primary aim of establishing the temporal relationship of structure and function in athletes of varying sporting demographics. 92 male athletes were studied [Group IA, (low static–low dynamic) (n?=?20); Group IC, (low static–high dynamic) (n?=?25); Group IIIA, (high static–low dynamic) (n?=?21); Group IIIC, (high static–high dynamic) (n?=?26)]. Conventional echocardiography of both the left ventricles (LV) and right ventricles (RV) was undertaken. An assessment of simultaneous longitudinal strain and LV volume/RV area was provided. Data was presented as derived strain for % end diastolic volume/area. Athletes in group IC and IIIC had larger LV end diastolic volumes compared to athletes in groups IA and IIIA (50?±?6 and 54?±?8 ml/(m²)^1.5 versus 42?±?7 and 43?±?2 ml/(m²)^1.5 respectively). Group IIIC also had significantly larger mean wall thickness (MWT) compared to all groups. Athletes from group IIIC required greater longitudinal strain for any given % volume which correlated to MWT (r?=?0.4, p?<?0.0001). Findings were similar in the RV with the exception that group IIIC athletes required lower strain for any given % area. There are physiological differences between athletes with the largest LV and RV in athletes from group IIIC. These athletes also have greater resting longitudinal contribution to volume change in the LV which, in part, is related to an increased wall thickness. A lower longitudinal contribution to area change in the RV is also apparent in these athletes.     

Radiotherapy-induced global and regional differences in early-stage left-sided versus right-sided breast cancer patients: speckle tracking echocardiography study

Radiotherapy (RT) to the thoracic region increases late cardiovascular morbidity and mortality. The impact of breast cancer laterality on cardiac function is largely unknown. The aim of this prospective study was to compare RT-induced changes in left-sided and right-sided breast cancer patients using speckle tracking echocardiography (STE). Sixty eligible patients with left-sided breast cancer and 20 with right-sided breast cancer without chemotherapy were evaluated prospectively before and early after RT. A comprehensive echocardiographic examination included three dimensional measurements and STE of the left ventricle (LV). The global longitudinal strain (GLS) was reduced from ?18.3?±?3.1 to ?17.2?±?3.3% (p?=?0.003) after RT in patients with left-sided breast cancer. Similarly, regional analysis showed a reduction in the apical strain from ?18.7?±?5.3 to ?16.7?±?4.9% (p?=?0.002) and an increase in basal values from ?21.6?±?5.0 to ?23.3?±?4.9% (p?=?0.024). Patients with right-sided breast cancer showed deterioration in basal anterior strain segments from ?26.3?±?7.6 to ?18.8?±?8.9% (p?<?0.001) and in pulsed tissue Doppler by 0.825 [0.365, 1.710] cm/s (p?<?0.001). In multivariable analysis, the use of aromatase inhibitor (β?=??2.002, p?=?0.001) and decreased LV diastolic volume (β?=??0.070, p?=?0.025) were independently associated with the decrease in GLS. RT caused no changes in conventional LV systolic measurements. RT induced regional changes corresponded to the RT fields. Patients with left-sided breast cancer experienced apical impact and global decline, whereas patients with right-sided breast cancer showed basal changes. The regional differences in cardiac impact warrant different methods in screening and in the follow-up of patients with left-sided versus right-sided breast cancer.     

Left ventricular torsion and circumferential strain responses to exercise in patients with ischemic coronary artery disease

LV torsion during exercise in patients with coronary artery disease (CAD) is not well known. Circumferential strain (CS) and left ventricular (LV) torsion (Tor) have not been evaluated during ischemia in these patients. We aimed to assess the effect of ischemia during exercise echocardiography (ExE) on CS and Tor. We studied a group of 73 patients with true positive ExE results (Ischemic group: ischemia plus an abnormal coronary angiogram) and a matched control group of 66 patients with negative ExE and either normal coronary angiography or low post-test probability of CAD. Basal rotation (Rot) and apical rotation and basal and apical CS were studied by speckle tracking at rest and exercise. Apical CS and apical and basal Rot values were similar between groups at rest, except basal CS which was already worse in the ischemic group. At exercise, all rotational and CS parameters were impaired in the ischemic in comparison with the control group (basal CS: ?18?±?5 vs. ?25?±?7?%, p?<?0.001; apical CS: ?31?±?11 vs. ??43?±?9?%, p?<?0.001; time to basal CS: 52?±?6 vs. 48?±?7?%, p?=?0.001; time to apical CS: 55?±?7 vs. 49?±?6?%, p?<?0.001; basal rotation: ?0.7?±?6.5° vs. ?6.2?±?8.5°, p?<?0.001; LV twist 13.0?±?10.4° vs.19.7?±?11.5°, p?<?0.001; LV-Tor 1.9?±?1.6°/cm vs. 2.8?±?1.7?/cm, p?=?0.001) with the exception of apical rotation which was similar (12.3?±?7.4° vs. 13.4?±?7.7°, p?=?NS). Basal and apical CS and basal rotation impair during exercise-induced ischemia. LV-Tor decreases with ischemia due to worsening of basal rotation, whereas apical rotation does not impair, suggesting the existence of an apical compensatory mechanism.     

Reproducibility of peak filling and peak emptying rate determined by cardiovascular magnetic resonance imaging for assessment of biventricular systolic and diastolic dysfunction in patients with pulmonary arterial hypertension

Right ventricular (RV) and left ventricular (LV) diastolic stiffness may be independent contributors to disease progression in pulmonary arterial hypertension (PAH). The aims of this study are to assess reproducibility of peak emptying rate (PER) and early diastolic peak filling rate (PFR) for both the RV and the LV in PAH and study their relationship to stroke volume (SV). Triple weekly repetition of 20 (totalling 60) cardiovascular magnetic resonance (CMR) scans, were done on 10 patients with PAH and 10 healthy controls. RV and LV volumes were measured over the full cardiac cycle. PER and PFR were calculated as the first derivative of the time–volume relationship in both the RV and the LV and indexed to body surface area. Reproducibility and the relation to SV were studied in a mixed model. PFR was lower in PAH in both the RV (PAH?=?170 mL/m²/s, controls?=?236 mL/m²/s [p?<?0.01]) and in the LV (PAH?=?209 mL/m²/s, controls?=?311 mL/m²/s [p?<?0.01]). PERs were not significantly different between patients and controls. Reproducibility of PER and PFR was high. A trial targeting normalization of PFR requires a total sample size of <?20. PER and PFR in both ventricles were strongly associated with stroke volume (all four: p?<?0.01). Biventricular diastolic dysfunctions are strongly associated with stroke volume, and CMR can quantify them with high reproducibility, enabling small sample sizes for trials of therapies targeting diastolic dysfunction to increase survival.     

Improving the role of echocardiography in studying the right ventricle of repaired tetralogy of Fallot patients: comparison with cardiac magnetic resonance

Right ventricular (RV) evaluation represents one of the major clinical tasks in the follow-up of repaired tetralogy of Fallot patients (rToF) with pulmonary valve regurgitation, as both severe RV dilatation and dysfunction are key factors in defining the need of pulmonary valve replacement. The aim of our study was to report the diagnostic accuracy of echocardiography in the identification of rToF patients with severely dilated and/or depressed RV as compared to cardiac magnetic resonance (CMR). Among our patients with rToF, a subgroup of 95 (17.6?±?6.8 years; 60% male), who underwent right ventricular qualitative and quantitative evaluation with CMR following echocardiographic suspicion of severe dilation/dysfunction, were included in the analysis. When comparing echocardiographic RV functional parameters to CMR findings, we found no association between CMR-ejection fraction (EF) and either tricuspid annulus plane systolic excursion (TAPSe) nor tissue Doppler systolic tricuspid excursion velocity (all p?=?ns). In contrast RVFAC was strongly associated with CMR-EF (r?=?0.44; p?<?0.01) as well as to longitudinal components of RV mechanics including tissue Doppler s′ (r?=?0.40; p?<?0.01) and TAPSE (r?=?0.36; p?<?0.01). When comparing echocardiographic and CMR structural parameters of the RV, we found that CMR RV volume was strongly related to echocardiographic measurements of RV end diastolic area (from the 4 chamber apical view) and with proximal parasternal short axis right ventricle outflow-dimension. Accordingly a regression model was derived from multiple regression analysis, which allows a more accurate estimate of CMR RV volume from echocardiography (r²?=?0.59, p?<?0.001). Our study demonstrates a significant, although imperfect, correlation between echocardiographic and CMR RV functional and geometrical parameters. Combining echocardiographic measures of RV inflow and RV outflow, we deliver a simple formula to estimate CMR-RV volume, improving the echocardiographic accuracy in RV volume quantification.     

Association between left ventricular mechanics and diffuse myocardial fibrosis in patients with repaired Tetralogy of Fallot: a cross-sectional study

Background

Patients with repaired tetralogy of Fallot (TOF) have progressive, adverse biventricular remodeling, leading to abnormal contractile mechanics. Defining the mechanisms underlying this dysfunction, such as diffuse myocardial fibrosis, may provide insights into poor long-term outcomes. We hypothesized that left ventricular (LV) diffuse fibrosis is related to impaired LV mechanics.

Methods

Patients with TOF were evaluated with cardiac magnetic resonance in which modified Look-Locker (MOLLI) T1-mapping and spiral cine Displacement encoding (DENSE) sequences were acquired at three LV short-axis positions. Linear mixed modeling was used to define the association between regional LV mechanics from DENSE based on regional T1-derived diffuse fibrosis measures, such as extracellular volume fraction (ECV).

Results

Forty patients (26?±?11 years) were included. LV ECV was generally within normal range (0.24?±?0.05). For LV mechanics, peak circumferential strains (?15?±?3%) and dyssynchrony indices (16?±?8 ms) were moderately impaired, while peak radial strains (29?±?8%) were generally normal. After adjusting for patient age, sex, and regional LV differences, ECV was associated with log-adjusted LV dyssynchrony index (β?=?0.67) and peak LV radial strain (β?=??0.36), but not LV circumferential strain. Moreover, post-contrast T1 was associated with log-adjusted LV diastolic circumferential strain rate (β?=?0.37).

Conclusions

We observed several moderate associations between measures of fibrosis and impaired mechanics, particularly the LV dyssynchrony index and peak radial strain. Diffuse fibrosis may therefore be a causal factor in some ventricular dysfunction in TOF.

     

Geometrical and functional cardiac changes after cardiac surgery: a phisiopatological explanation based on speckle tracking

Cardiac surgery induces geometrical and functional changes, which are not clearly explained. Objective: to investigate the physiopathology of the heart after cardiac surgery using advanced techniques of echocardiography. Thirty patients undergoing cardiac surgery had echocardiographic study prior and after surgery. Left and right ventricular (RV) longitudinal displacement and strain were studied with speckle-tracking. Using longitudinal displacement, we defined a static longitudinal reference-point (sLRP) to which the other segments moved during systole. Transversal displacement and global function were determined by conventional-echo. Left and RV segments showed systolic longitudinal displacement towards the apex, which was the sLRP before surgery; and towards the medium segment of lateral RV-wall one week after surgery. The displacement of basal RV segment towards this sLRP was smaller, causing decreased TAPSE. Apical segments showed an inverse displacement towards the new sLRP, and septum displacement was decreased or inverted towards the lateral RV-wall, causing paradoxus septal motion. RV-wall longitudinal strain was reduced (??23.1?±?8.6 vs. ??14.6?±?5.3;p?<?0.001), RV transversal fractional shortening was increased (36.5?±?10.5 vs. 41.7?±?13; p?=?0.011), and the RV fractional area change was unchanged (46.7?±?9.5 vs. 47.8?±?11.7; p?=?0.625). The medium segment of RV lateral wall, in contact with sternotomy, remains static after surgery and acts as a new sLRP towards which the rest of segments move, explaining the reduction of TAPSE and paradoxus septal motion. The longitudinal strain of the lateral RV-wall gets impaired, but an increase of transversal motion maintains global RV function.     

Balloon pulmonary angioplasty improves interventricular dyssynchrony in patients with inoperable chronic thromboembolic pulmonary hypertension: a cardiac MR imaging study

To use cardiac magnetic resonance imaging (MRI) to investigate the effect of balloon pulmonary angioplasty (BPA) on interventricular dyssynchrony and its associations with ventricular interaction, which impairs LV function in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). This prospective observational study was approved by our institutional review board. Cardiac MRI and right heart catheterization were conducted before BPA sessions and at the follow up after BPA in 20 patients with CTEPH. We measured right ventricular (RV) and left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) using MRI. For the LV and RV free walls, the time to peak (T_peak) of circumferential strain was calculated as a parameter for interventricular dyssynchrony. Following BPA, the RV-EDV and -ESV were significantly decreased, and the RVEF was significantly increased. Conversely, BPA led to significantly increased LV EDV and SV without changing LVESV. The left-to-right free wall delay (L–R delay) in T_peak strain decreased from 105?±?44 ms to 47?±?67 ms (p?<?0.001). Increased LV EDV (r?=?0.65, p?<?0.01), SV (r?=?0.74, p?<?0.001) and 6-minute walk distance (6MWD) (r?=?0.54, p?<?0.05) were correlated to the reduction in L–R delay. In patients with inoperable CPEPH, BPA improved interventricular dyssynchrony, which was strongly associated with increased SV and 6MWD. The assessment of interventricular dyssynchrony using cardiac MRI has an important role in evaluating ventricular interaction, which reduces LVSV and exercise tolerance.     

The consistency of myocardial strain derived from heart deformation analysis

The purpose of this study was to assess the consistency of semi-automated myocardial strain analysis by prototype software across field strengths, temporal resolutions, and examinations. 35 volunteers (48?±?13 years; 20% women) and 25 patients (54?±?12 years; 44% women) without significant cardiac dysfunction underwent cine cardiac magnetic resonance imaging (CMR) at 1.5 T with a temporal resolution of 39.2 msec. 34 subjects also underwent imaging at 3.0 T; 16 had repeat examinations within 14 days; and 9 underwent CMR with temporal resolutions of 12.5 and 39.2 msec on the same day. Prototype heart deformation analysis (HDA) software was used to retrospectively quantify strain from segmented balanced steady state free precession (bSSFP) cinegraphic images. Myocardial contours were automatically generated on short axis images and drawn at end-diastole by two independent reviewers on long-axis images. Contours were automatically propagated throughout the cardiac cycle. Global and regional peak systolic strain were compared across observers, field strengths, temporal resolutions, and examinations. Inter-observer agreement was excellent (ICC?>?0.87, p?<?0.01). Inter-examination variability was low, ranging from 1.7 (1.0–2.4)% to 2.5 (1.9–3.1)%, except for radial strain: 9.2 (7.6–10.5)%. Most global and regional strain values were not significantly different across field strengths and temporal resolutions (p?>?0.05). Normal global peak systolic strain values with HDA were ?25.0 (?24.0 to ?26.1)% (LV circumferential), 60.5 (55.3 to 65.6)% (LV radial), ?22.3 (?20.5 to ??24.0)% (LV longitudinal), and ?26.0 (?23.8 to ?28.2)% (RV longitudinal). HDA prototype software enabled efficient and consistent quantification of myocardial strain from conventional bSSFP cine CMR data, demonstrating clinical feasibility.