Multiplanar reconstruction of three-dimensional transthoracic echocardiography improves the presurgical assessment of mitral prolapse

Three-dimensional printing of mitral valve models using echocardiographic data improves the knowledge of cardiology fellow physicians in training

Background

High fidelity three-dimensional Mitral valve models (3D MVM) printed from echocardiography are currently being used in preparation for surgical repair.

Aim

We hypothesize that printed 3DMVM could have relevance to cardiologists in training by improving their understanding of normal anatomy and pathology.

Methods

Sixteen fellow physicians in pediatric and adult cardiology training were recruited. 3D echocardiography (3DE) video clips of six mitral valves (one normal and five pathological) were displayed and the fellows were asked to name the prolapsing segments in each. Following that, three still images of 3D MVMs in different projections: enface, profile and tilted corresponding to the same MVs seen in the clip were presented on a screen. Participating physicians were presented with a comprehensive questionnaire aimed at assessing whether the 3D MVM has improved their understanding of valvular anatomy. Finally, a printed 3D MVM of each of the valves was handed out, and the same questionnaire was re-administered to identify any further improvement in the participants' perception of the anatomy.

Results

The correct diagnosis using the echocardiography video clip of the Mitral valve was attained by 45% of the study participants. Both pediatric and adult trainees, regardless of the year of training demonstrated improved understanding of the anatomy of MV after observing the corresponding model image. Significant improvement in their understanding was noted after participants had seen and physically examined the printed model.

Conclusion

Printed 3D MVM has a beneficial impact on the cardiology trainees' understanding of MV anatomy and pathology compared to 3DE images.

Understanding Non-P2 Mitral Regurgitation Using Real-Time Three-Dimensional Transesophageal Echocardiography: Characterization and Factors Leading to Underestimation

BACKGROUND

P2 prolapse is a common cause of degenerative mitral regurgitation (MR); echocardiographic characteristics of non-P2 prolapse are less known. Because of the eccentric nature of degenerative MR jets, the evaluation of MR severity is challenging. The aim of this study was to test the hypotheses that (1) the percentage of severe MR determined by transthoracic echocardiography (TTE) would be lower compared with that determined by transesophageal echocardiography (TEE) in patients with non-P2 prolapse and also in a subgroup with "horizontal MR" (a horizontal jet seen on TTE that hugs the leaflets without reaching the atrial wall, particularly found in non-P2 prolapse) and (2) the directions of MR jets between TTE and real-time (RT) three-dimensional (3D) TEE would be discordant.

METHODS

One hundred eighteen patients with moderate to severe and severe degenerative MR defined by TEE were studied. The percentage of severe MR between TTE and TEE was compared in P2 and non-P2 prolapse groups and in horizontal and nonhorizontal MR groups. Additionally, differences in the directions of the MR jets between TTE and RT 3D TEE were assessed.

RESULTS

Eighty-six percent of patients had severe MR according to TEE. TTE underestimated severe MR in the non-P2 group (severe MR on TTE, 57%; severe MR on TEE, 85%; P < .001) but not in the P2 group (severe MR on TTE, 79%; severe MR on TEE, 91%; P = .157). Most "horizontal" MR jets were found in the non-P2 group (85%), and this subgroup showed even more underestimation of severe MR on TTE (TTE, 22%; TEE, 89%; P < .001). There was discordance in MR jet direction between two-dimensional TTE and RT 3D TEE in 41% of patients.

CONCLUSIONS

Non-P2 and "horizontal" MR are significantly underestimated on TTE compared with TEE. There is substantial discordance in the direction of the MR jet between RT 3D TEE and TTE. Therefore, TEE should be considered when these subgroups of MR are observed on TTE.

Level of agreement in three-dimensional planimetric measurement of mitral valve area between transthoracic and transesophageal echocardiography

BACKGROUND

Echocardiographic measurement of mitral valve area (MVA) is critical prior to percutaneous transmitral commissurotomy (PTMC). This study aimed to compare the agreement between transthoracic (TTE) and transesophageal echocardiography (TEE) in three-dimensional (3D) planimetric measurement of the MVA among patients with severe mitral stenosis.

METHODS

MVA was measured with planimetry in 105 patients before undergoing PTMC. 3D reconstruction was applied to both TTE and TEE examinations. The MVA values from four different methods of 3D reconstruction were compared to the average values of 3D methods in TEE as the gold standard measurement method for the MVA in this study. The agreement levels between the two examinations were evaluated and analyzed for various reconstruction methods.

RESULTS

The mean age was 49 ± 12 years for 28 men and 77 women who were enrolled. The image quality was graded as "excellent" in 57% of 3D images obtained by TTE, while it was graded as "excellent" in 81% of 3D images obtained by TEE. The ventricular zooming method in TTE with a bias of -0.006 ± 0.065 cm² (P < 0.0001) had the highest agreement with the 3D-MVA in TEE. While 2D-TTE and 3D-TEE measurements of the MVA (R = 0.91; P < 0.0001) were significantly correlated, 2D-TTE overestimated the MVA by 0.19 cm² .

CONCLUSION

Although the quality of 3D images was significantly better in TEE than those in TTE, a good agreement existed between the measured 3D-TTE and 3D-TEE studies. We also demonstrated that 2D-TTE overestimated the MVA compare to 3D-TEE.

A Modified Echocardiographic Classification of Mitral Valve Regurgitation Mechanism: The Role of Three-dimensional Echocardiography

In this report, we provide an overview of a new, updated echocardiographic classification of mitral regurgitation mechanisms to provide a more comprehensive and detailed assessment of mitral valve disorders. This is relevant to modern mitral valve repair techniques, with special attention to the added value of 3D-echocardiography.

The mechanisms, diagnosis and management of mitral regurgitation in mitral valve prolapse and hypertrophic cardiomyopathy

Valvular disease is a frequent cardiac pathology leading to heart failure and, ultimately, death. Mitral regurgitation, defined as the inability of the two mitral leaflets to coapt, is a common valvular disease and a self sustained pathology. A better understanding of the mitral valve histological layers provides a better understanding of the leaflet and chordae changes in mitral valve prolapse. Mitral valve prolapse may occur in myxomatous degenerative abnormalities, connective tissue disorders or in sporadic isolated cases. It is the most common mitral abnormality of non-ischemic cause leading to severe surgery-requiring mitral regurgitation. In addition to standard echocardiographic investigations, newly implemented three-dimensional techniques are being used and they permit a better visualisation, from the so-called ‘surgical view’, and an improved evaluation of the mitral valve. Hypertrophic cardiomyopathy is the most frequent inherited myocardial disease caused by mutations in various genes encoding proteins of the cardiac sarcomere, leading to a marked left ventricular hypertrophy unexplained by other comorbidities. The pathological echocardiographic hallmarks of hypertrophic cardiomyopathy are left ventricular hypertrophy, left ventricular outflow tract obstruction and systolic anterior motion of the mitral valve. The systolic anterior motion of the mitral valve contributes to the development of mitral regurgitation and further narrows the left ventricular outflow tract, leading to more severe symptomatology. Cardiac magnetic resonance imaging accurately measures the left ventricular mass, the degree of diastolic function and it may also be used to distinguish phenotypic variants. The clinical outcome of patients with these pathologies is mostly determined by the selected option of treatment. The purpose of surgical correction regarding mitral valve involvement is to restore valvular competence. Surgery has proven to be the only useful treatment in preventing heart failure, improving symptomatology and reducing mortality. Our approach wishes to enhance the understanding of the mitral valve’s involvement in hypertrophic cardiomyopathy and mitral valve prolapse from genetic, haemodynamic and clinical perspectives, as well as to present novelties in the grand field of treatment.

The role of experience in echocardiographic identification of location and extent of mitral valve prolapse with 2D and 3D echocardiography

Contradiction exists on the incremental value of two-dimensional (2D) and 3D transoesophageal echocardiography (TOE) over 2D transthoracic echocardiography (TTE) for the detection of mitral valve (MV) prolapse in readers with different echocardiographic experience. Twenty patients and five healthy persons were retrospectively identified who had undergone 2D-TTE, 2D-TOE and 3D-TOE. Fifteen (75 %) patients had surgical evidence of prolapse of the posterior MV leaflet and five patients (25 %) had a dilated MV annulus without prolapse. Three reader groups with different echocardiographic expertise (novice, trainees, cardiologists) scored thus in total 675 posterior scallops. Overall there was an improvement in agreement and Kappa values from novice to trainees to cardiologists. Diagnostic accuracies of 2D-TOE were higher than those of 2D-TTE mainly in novice readers. The incremental value of 3D-TOE over 2D-TOE was mainly seen in specificities. Time to diagnosis was dramatically reduced from 2D to 3D-TEE in all reader groups (all P < 0.001). 3D-TOE also improved the agreement (+12 to +16 %) and Kappa values (+0.14 to +0.21) in all reader groups for the exact description of P2 prolapse. Differences between readers with variable experience in determining the precise localization and extent of the prolapsing posterior MV scallops exist in particular in 2D-TTE analysis. 3D-TOE analysis was extremely fast compared to the 2D analysis methods and showed the best diagnostic accuracy (mainly driven by specificity) with identification of P1 and P3 prolapse still improving from novice to trainees to cardiologists and provided optimal description of P2 prolapse extent.

Transthoracic two-dimensional xPlane and three-dimensional echocardiographic analysis of the site of mitral valve prolapse

This study sought to assess the value of two-dimensional (2D) transthoracic echocardiography (TTE), 2D xPlane imaging and three-dimensional (3D) TTE for the definition of the site and the extent of mitral valve (MV) prolapse. Fifty patients underwent transthoracic 2D, 2D xPlane and 3D echocardiography. With 2D xPlane a segmental analysis of the MV was performed, by making a lateral sweep across the MV coaptation line as seen in the parasternal short-axis view. Inter-observer agreement for specific scallop prolapse was for 2D xPlane excellent (97 %, kappa = 0.94) and for 3D TTE moderate (85 %, kappa = 0.67). The respective sensitivities of standard 2D TTE, 2D xPlane, and 3D TTE for the identification of the precise posterior scallop prolapse were for P1 92, 85, and 92 %, for P2 96, 96, and 82 %, and for P3 86, 81, and 71 %. In total, 5 (8 %) prolapsing MV scallops were missed by 2D TTE, 7 (12 %) by 2D xPlane, and 12 (20 %) by 3D TTE. The sensitivity of 3D TTE was significantly lower than standard 2D imaging (80 % versus 93 %, P < 0.05). The extent of P2 prolapse was under or overestimated in 5 patients with 2D xPlane and in 9 patients with 3D TTE. 2D xPlane imaging is an accurate, easy to use (compared to 3D TTE) and easy to interpret (compared to 2D and 3D TTE) imaging modality to study the site and the extent of MV prolapse.

Identification of prolapsing mitral valve scallops by a three-dimensional multiplanar reconstruction method

BACKGROUND

The objectives of this study were twofold: to assess the diagnostic utility of three-dimensional (3D) multiplanar reconstruction (MPR) in identifying prolapsing mitral valve (MV) scallops, and (2) to compare two-dimensional (2D) transthoracic echocardiography (TTE) and 3DMPR to (2D) transesophageal echocardiography (TEE) approaches among patients with mitral valve prolapse (MVP).

METHODS

Fifty-five patients with MVP who underwent MV repair or replacement were retrospectively analyzed using 3 types of echocardiographic studies (2DTEE, 2DTTE, 3DMPR). The operative (OR) findings were considered the gold standard.

RESULTS

When 3DMPR was combined with 2DTTE, the agreement with the OR findings was moderately strong for the A2 scallop (P < 0.001) and strong for the A3 scallop (P = 0.001), entire anterior leaflet (P < 0.001), P2 scallop (P < 0.001) and the entire posterior leaflet (P < 0.001). In comparison to the OR findings, 2DTEE demonstrated moderately strong agreement for the A2 scallop (P = 0.010) and the entire anterior leaflet (P < 0.001), and strong agreement for the P2 scallop (P < 0.001) and entire posterior leaflet (P < 0.001).

CONCLUSIONS

Three-dimensional MPR should be added to the armamentarium of complementary echo techniques in the evaluation of MVP. There is increased benefit in combining 3DMPR with 2DTTE findings as part of the preoperative evaluation of patients with MVP.

Mitral valve prolapse: role of 3D echocardiography in diagnosis

PURPOSE OF REVIEW

To review the utility and the latest developments in three-dimensional (3D) echocardiography of mitral valve prolapse.

RECENT FINDINGS

Although 3D echocardiography was invented in 1974, it did not gain wide clinical acceptance until the introduction of real-time 3D echocardiography in the first decade of the 21st century. Driven by improvements in probe technology and increases in computing power, 3D echocardiography now provides unprecedented images of mitral valve prolapse and its associated mitral regurgitation with no or minimal requirements for image post processing.

SUMMARY

3D echocardiography has become the echocardiographic modality of choice for establishing the diagnosis, describing the precise anatomy, and visualization of mitral regurgitant jets in mitral valve prolapse. 3D echocardiography is becoming indispensable in guiding surgical and percutaneous methods of mitral valve repair and replacement.

Real-time three-dimensional transesophageal echocardiography for assessment of mitral valve functional anatomy in patients with prolapse-related regurgitation

The aim of the study was to evaluate the additional diagnostic value of real-time 3-dimensional transesophageal echocardiography (RT3D-TEE) for surgically recognized mitral valve (MV) prolapse anatomy compared to 2-dimensional transthoracic echocardiography (2D-TTE), 2D-transesophageal echocardiography (2D-TEE), and real-time 3D-transthoracic echocardiography (RT3D-TTE). We preoperatively analyzed 222 consecutive patients undergoing repair for prolapse-related mitral regurgitation using RT3D-TEE, 2D-TEE, RT3D-TTE, and 2D-TTE. Multiplanar reconstruction was added to volume-rendered RT3D-TEE for quantitative prolapse recognition. The echocardiographic data were compared to the surgical findings. Per-patient analysis of RT3D-TEE identified prolapse in 204 patients more accurately (92%) than 2D-TEE (78%), RT3D-TTE (80%), and 2D-TTE (54%). Even among those 60 patients with complex prolapse (>1 segment localization or commissural lesions), RT3D-TEE correctly identified 58 (96.5%) compared to 42 (70%), 31 (52%), and 21 (35%) detected by 2D-TEE, RT3D-TTE, and 2D-TTE (p < 0.0001). Multiplanar reconstruction enabled RT3D-TEE to differentiate dominant (≥5-mm displacement) and secondary (2 to <5-mm displacement) prolapsed segments in agreement with surgically recognized dominant lesions (100%), but with a low predictive value (34%) for secondary lesions. In addition, owing to the identification of clefts and subclefts (indentations of MV tissue that extended ≥50% or <50% of the total leaflet height, respectively), RT3D-TEE accurately characterized the MV anatomy, including that which deviated from the standard nomenclature. In conclusion, RT3D-TEE provided more accurate mapping of MV prolapse than 2D imaging and RT3D-TTE, adding quantitative recognition of dominant and secondary lesions and MV anatomy details.

Preoperative scallop-by-scallop assessment of mitral prolapse using 2D-transthoracic echocardiography

Background

This study was conducted to assess the accuracy of harmonic imaging 2D-transthoracic echocardiography (2D-TTE) segmental analysis compared to surgical findings, in degenerative mitral regurgitation (MR).

Methods

Seventy-seven consecutive patients with severe degenerative MR were prospectively enrolled. Preoperative 2D-TTE with precise localization of prolapsing or flailing scallops/segments was performed. All patients underwent mitral valve surgical repair. Surgical reports (SR), including valve description, were used as references for comparisons. A postoperative control 2D-TTE was performed.

Results

Out of 462 scallops/segments studied, surgical inspection identified 102 prolapses or flails (22%), 92 of which had previously been detected by 2D-TTE (90.2% sensitivity, 100% specificity). Agreement between preoperative 2D-TTE segmental analysis and SR was 97.8% (k = 0.93; p < 0.0001). Sixty-nine out of 77 2D-TTE reports were completely concordant with SR (89.6% diagnostic accuracy). None of the 8 non-concordant 2D-TTE reports were in complete disagreement with SR. P2 scallop was always involved in posterior leaflet prolapse or flail and was described correctly by 2D-TTE in 68 out of 69 patients (98,7% agreement, k = 0,93; 98.5% sensitivity). The anterior leaflet was involved in 14 patients (18%); A2 segment was involved in all of those cases and was correctly detected by 2D-TTE in 13 (98,7% agreement, k = 0,95; 92,8% sensitivity). Antero-lateral and postero-medial para-commissural prolapse or flail had a lower prevalence (14% and 10% respectively), with 2D-TTE sensitivity respectively of 64% and 50%.

Conclusions

2D-TTE, performed by an experienced echo-lab, has very good diagnostic accuracy in localizing the scallops/segments involved in degenerative MR, particularly for the middle ones (P2-A2), which represent almost the totality of prolapses. More invasive, time consuming and expensive exams should be reserved to selected cases.