Intracardiac device associated interference with tricuspid valve apparatus on echocardiography: What can we learn from pathology?

Funding Acknowledgements

Type of funding sources: None.

Background

 New or worsening tricuspid regurgitation (TR) is associated with right-sided heart failure and worsened outcomes. Cardiac Implantable Electronic Devices (CIEDs), which are being implanted at growing rates worldwide, are increasingly being recognized as associated with TR occurrence related to interference with the tricuspid valve (TV) apparatus. Purpose: We sought to identify echocardiographic features in the right ventricle and TV that differentiate patients who have anatomically demonstrated interference with the TV on direct pathology inspection. 

Methods

 Explanted hearts from 44 consecutive patients undergoing orthotopic heart transplant (55 ±13 yrs, 68% men) with known implanted CIEDs were dissected to assess the presence (n = 18) or absence (n = 26) of CIED interference with the TV (Figure). Echocardiographic measurements performed prior to transplantation, including left and right ventricular (LV, RV) size and performance metrics as well as TR severity, were compared between both groups using non-parametric testing. 

Results

 Echocardiographic features of patients with and without anatomically demonstrated TV interference are shown in the Table. Although overall LV dimensions and volumes were not different between the two groups and LV ejection fraction was severely reduced in both groups, patients demonstrating CIED interference trended towards larger right atrial volumes (Table) and also larger RV and tricuspid annular sizes. Importantly, however, they were more than 4 times likely to have abnormal right ventricular function. Lastly, patients with tricuspid apparatus interference tended to have more significant TR, although these differences have not reached statistical significance (Table). 

Conclusion

 CIED interreference with tricuspid valve apparatus occurs frequently (41%) among patients with CIEDs, who undergo orthotopic heart transplantation. This may be associated with worsening TV function with subsequent changes in right atrial and ventricular geometry and function. In light of prior data showing poor outcomes with CIED associated TR, this study emphasizes the importance of non-invasive assessment of CIED interference with the tricuspid valve, in order to improve device placement and patient outcomes. Abstract Figure  Abstract Table

Restoration of normal sinus rhythm in atrial fibrillation: impact of reverse remodelling of right chambers on tricuspid regurgitation severity

Background

The severity of tricuspid regurgitation (TR) in patients with restored normal sinus rhythm (SR) after atrial fibrillation (AF) has been poorly assessed.

Purpose

Our study aimed to assess (1) right chamber remodelling and (2) TR severity in patients with AF who have had their rhythms restored to normal sinus.

Methods

We prospectively evaluated 94 consecutive patients hospitalized for AF who received either ablation, direct current cardioversion, or pharmacological therapy. Patients were divided into two groups according to their cardiac rhythm at 6 months follow up (6M): restoration to SR (SR group, n=54), persistence of AF (AF group, n=40). TR vena contracta (VC), TR grade severity was divided into 4 grades using an integrated approach (0: none or trace; 1: mild; 2: moderate; 3: severe TR). Two dimensional (2D) end diastolic (ED) tricuspid annulus (TA) diameter in the apical 4 chambers view, three-dimensional (3D) indexed volumes (3D Vi) of the right atrium (RA) and right ventricle (RV) in end systole (ES) and ED were acquired using transthoracic echocardiography at admission and at 6M.

Results

At 6M, in the SR group a significant improvement in TR VC (Figure A) and TR grade (Figure B) were noted, whereas there was no differences in the AF group (0.41 vs. 0.42cm, p=0.24 for TR VC; 1.70 vs. 1.76, p=0.16 for mean TR grade). In the SR group a significant reduction in 3D ES RV Vi, 2D ED TA diameter, 3D ES and ED Vi of the RA (Table) were observed. Regression of TR VC was correlated with regression of right cavities parameters (ρ=0.47, p<0.001 for 2D ED TA diameter; ρ=0.34, p<0.005 for 3D ES RA Vi; ρ=0.33, p<0.005 for 3D ED RV Vi; ρ=0.29, p<0.005 for 3D ES RV Vi).

Conclusion

Restoration of normal SR in patients with AF results in beneficial remodelling of right cavities at 6M of follow-up which were associated with a significant decrease in TR severity. Strategies for normal SR restoration in patients with AF and TR should be vigorously attempted.

TR Evolution

Funding Acknowledgement

Type of funding source: None

Impact of rhythm in non-valvular atrial fibrillation on four cardiac chamber deformation imaging

Background

Few studies have assessed the evolution of cardiac chambers deformation imaging in patients with atrial fibrillation (AF) according to cardiac rhythm outcome.

Purpose

To evaluate cardiac chamber deformation imaging in patients admitted for AF and the evolution at 6-month follow-up (M6).

Methods

In forty-one consecutive patients hospitalised for AF two-dimensional transthoracic echocardiography was performed at admission (M0) and after six months (M6) of follow up. In addition to the usual parameters of chamber size and function, chamber deformation imaging was obtained including global left atrium (LA) and right atrium (RA) reservoir strain, global left ventricular (LV) and right ventricular (RV) free wall longitudinal strain. Patients were divided into three groups according to their cardiac rhythm at M0 and M6: AF at M0 and sinus rhythm (SR) at M6 (AF-SR) (n=23), AF at M0 and AF at M6 (AF-AF) (n=11), SR at M0 (spontaneous conversion before the first echocardiography exam) and SR in M6 (SR-SR) (n=7)

Results

In comparison with SR patients (n=7), at M0, AF patients (n=34)) had lower global LA reservoir strain (+5.2 (+0.4 to 12.8) versus +33.2 (+27.0 to +51.5)%; p<0.001), lower global RA reservoir strain (+8.6 (−5.4 to 11.6) versus +24.3 (+12.3 to +44.9)%; p<0.001), lower global LV longitudinal strain (respectively −12.8 (−15.2 to −10.4) versus −19.1 (−21.8 to −18.3)%; p<0.001) and lower global RV longitudinal strain (respectively −14.2 (−17.3 to −10.7) versus −23.8 (−31.1 to −16.2)%; p=0.001). When compared with the AF-SR group at M0 the AF-AF group had no significant differences with regard to global LA and RA reservoir strain, global LV and RV longitudinal strain (Table). Between M0 and M6 there was a significant improvement in global longitudinal strain of the four chambers in the AF-SR group whereas no improvements were noted in the AF-AF and SR-SR group (Figure).

Conclusion

Initial atrial and ventricular deformations were not associated with rhythm outcome at six-month follow up in AF. The improvement in strain in all four chambers strain suggests global reverse remodelling all cardiac cavities with the restoration of sinus rhythm.

Evolution of strain between M0 and M6

Funding Acknowledgement

Type of funding source: None

P1766 Comparison of left ventricular stroke volume in healthy adults among regions around the world: results from the World Alliance of Societies of Echocardiography (WASE) Normal Values Study

Funding Acknowledgements

WASE Normal Values Study is sponsored by American Society Echocardiography Foundation.

OnBehalf

the WASE Investigators

Background

The American Society of Echocardiography (ASE) and the European Association of Cardiovascular Imaging (EACVI) chamber quantification guidelines provide normal reference values for a variety of size and function parameters. While used worldwide, these were predominantly obtained from American and European Caucasian populations and may not represent individuals from other regions around the world. Accordingly, ASE in collaboration with its International Alliance Partners conducted the World Alliance of Societies of Echocardiography (WASE) Normal Values Study to establish and compare normal echocardiographic values across races, ethnicities and countries worldwide. While most previous studies focused on left ventricular (LV) size and ejection fraction, LV stroke volume (SV) in healthy normal subjects has not been well defined. In this report, we aim to examine similarities and differences in normal LV SV indexed by body surface area (SVI) among regions around the world.

Methods

WASE Normal Values Study is a multinational, observational, cross-sectional study. Individuals free from known cardiac, lung and renal disease were prospectively enrolled with even distribution among age groups and gender. Echocardiographic images were acquired following a standardized protocol. LV SV was assessed by Doppler-derived (LVOT diameter and VTI) and two-dimensional (2D) biplane Simpson’s methods. LV SVI was calculated to account for differences in body size. These measurements were analyzed (TOMTEC) in a single core laboratory following ASE/EACVI Guidelines.

Results

As of May 2019, LV SV has been analyzed in 1164 cases from 13 countries, representing 8 distinct regions worldwide. In this population, age, body surface area and 2D LV ejection fraction were 47 ± 17 years old (range 18-87 years old), 1.76 ± 0.22 m² (range 0.95-2.44 m²) and 63.2 ± 2.9 % (range 52.7-73.7 %), respectively. LV SV and SVI by Doppler were larger than those obtained by 2D method in all regions. LV SV and SVI in both methods had significant differences among regions (p< 0.0001, Kruskal-Wallis test). LV SV and SVI in South Asia (India) were smallest in both methods and were also significantly smaller than other Asian regions (Figure). North America and Europe had largest LV SV and SVI by Doppler method, while Oceania had largest values by 2D.

Conclusions

The WASE Normal Values Study shows geographical variability in LV SVI across continents and countries. This information should be considered when determining normative values for SV and SVI.

Abstract P1766 Figure.

104 Left ventricular stroke volume differences among echocardiographic methods in healthy adults from the World Alliance of Societies of Echocardiography (WASE) Normal Values Study

Funding Acknowledgements

WASE Normal Values Study is sponsored by American Society Echocardiography Foundation.

OnBehalf

the WASE Investigators

Background

Left ventricular (LV) stroke volume (SV) can be determined by multiple ultrasound methods, including Doppler, two- (2D) and three-dimensional (3D) echocardiography. However, how methods compare to each other is not well understood. In this report from the WASE study, we aim to examine and compare normal reference ranges for SV and SV index (SVI) obtained from healthy adults by Doppler, 2D Simpson’s and 3D methods.

Methods

WASE Normal Values Study is a multinational, observational, cross-sectional study. Individuals free from known cardiac, lung and renal disease were prospectively enrolled with even distribution among age groups and gender. Doppler, 2D and 3D datasets were acquired at the enrolling centers, following a standardized protocol. LV SV was measured by three methods: Doppler (LV outflow tract diameter and velocity time integral), 2D biplane Simpson’s rule and 3D volume method. SV was indexed by body surface area (SVI). All measurements were analyzed (TOMTEC) in two core laboratories (for 2D and 3D) following ASE Guidelines. Methods were compared by Friedman test and Bland-Altman analysis.

Results

As of May 2019, 646 cases have been analyzed in both 2D and 3D datasets. In this population, age was 45 ± 16 years old (range 18-85) and body surface area was 1.76 ± 0.22 m² (range 0.95-2.44). LV EF by 2D Simpson’s rule and 3D method were 63.2 ± 2.9 and 62.3 ± 5.0 %, respectively (p < 0.0001, Wilcoxon test). SVI by Doppler, 2D and 3D were 39.6 ± 7.6, 33.8 ± 6.5 and 41.0 ± 9.4 ml/m², respectively. There were significant differences between the three methods (p < 0.0001, Friedman test). 2D underestimated SVI compared to Doppler by 14.6% (mean of differences 5.8 ml/m², p < 0.0001) and 3D by 17.6% (7.2 ml/m², p < 0.001). The difference between Doppler and 3D was smaller (3.4% lower by Doppler) but still statistically significant (1.4 ml/m², p = 0.0008). The results are shown in the figure.

Conclusions

Comparing 3 modalities in a large population of healthy individuals, SV and SVI are underestimated by 2D Simpson’s method. Given the large differences, combining 2D and Doppler or 3D measurements for hemodynamic calculations (such as regurgitant volumes and fraction) should be done with caution.

Abstract 104 Figure.

P3685Can 3D echocardiography give a contribute to the diagnosis of Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)?

Background

The diagnosis of ARVC is based on the structural assessment of the heart with 2D echocardiography (2DE) and cardiovascular MRI (CMR) to detect the presence of global and segmental right ventricular (RV) abnormalities. Little is known about the diagnostic value of 3D echocardiography (3DE) in ARVC. The aim of this study was to assess whether a combination of 2DE and 3DE could replace 2DE and CMR combination with similar diagnostic accuracy in patients with suspected ARVC.

Methods

Thirty-nine subjects (59% males, 47±15 years, 41% with desmosomal mutations) with suspected or confirmed diagnosis of ARVC underwent evaluation of the RV with the use of CMR, 2DE, 3DE.

3DE and CMR were independently used to obtain RV volumes, ejection fraction and presence of segmental RV abnormalities. These studies were blindly classified as meeting none, minor, or major criteria for ARVC in accordance with the 2010 TFC. Kappa statistics were used to assess the concordance between 2DE-CMR and 2DE-3DE diagnostic approaches.

Results

Using the 2DE-CMR approach, patients were classified as follows: 5 not affected, 8 with possible, 9 with borderline and 17 with definite ARVC diagnosis. The evaluation of TFC criteria with the 2DE-3DE approach yielded a high degree of concordance with the standard of care (2DE-CMR approach, K=0.93 with 95% CI: 0.84–1.0). There was complete agreement between the 2DE-CMR and 2DE-3DE approaches for individuals with definite ARVC diagnosis (n=17) and in individuals not affected by ARVC (n=5). Two patients with possible and borderline ARVC diagnosis using the 2DE-CMR approach were confirmed as definite ARVC with 2DE-3DE approach.

Contribution of 3D echo to ARVC

Conclusions

The use of 2D and 3D echocardiography allows bedside evaluation of patients with suspected ARVC, which is diagnostically comparable to that obtained using the traditional combination of 2DE-CMR. This information is particularly relevant for patients who cannot undergo CMR such as patients with ICD.

Novel flow cytometric analysis of the progress and route of internalization of a monoclonal anti-carcinoembryonic antigen (CEA) antibody

A flow cytometric method of studying the internalization of a monoclonal antibody (Mab) directed against carcinoembryonic antigen (CEA) has been compared with Western blotting, using three human colonic cancer cell lines which express varying amounts of the target antigen. Cell samples incubated for increasing time intervals with fluoresceinated or unlabelled Mab were analyzed using flow cytometry or polyacrylamide gel electrophoresis and Western blotting. SDS/PAGE analysis of cytosolic and membrane components of solubilized cells from the cell lines provided evidence of non-degraded internalized anti-CEA Mab throughout seven half hour intervals, starting at 5 min. Internalized anti-CEA was detected in the case of high CEA expressing cell lines (LS174T, SKCO1). Very similar results were obtained with an anti-fluorescein flow cytometric assay. Given that these two methods consistently provided comparable results, use of flow cytometry for the detection of internalized antibody is suggested as a rapid alternative to most currently used methods for assessing antibody internalization. The question of the endocytic route followed by CEA-anti-CEA complexes was addressed by using hypertonic medium to block clathrin mediated endocytosis.