A novel method to measure mitral valve area in patients with rheumatic mitral stenosis using three-dimensional transesophageal echocardiography: Feasibility and validation

Multi-modality imaging to assess rheumatic mitral stenosis severity

Multi-modality imaging is the recommended approach to assess the severity of valvular heart diseases. Rheumatic mitral stenosis (MS), however, has yet to benefit from this approach. The aim of this study is to assess the added value of cardiac MRI (CMR) and computed tomography (CT) calcium score in assessing severity of MS when compared to 3D echocardiography. Patients with MS in sinus rhythm were included. Both CMR and 3D echo assessments of the mitral valve were performed. Subsequently, three radiologists and three cardiologists independently measured mitral valve area (MVA). In addition, CT of the mitral valve was conducted. Mitral calcium score was calculated according the Agatston method. A total of 41 patients were included. CMR significantly overestimated MVA when compared to 3D echo MVA regardless of the investigator [F (1, 40) = 23.3, p < 0.001, η2 = 0.36]. The more severe the MS, the greater the overestimation by CMR compared to 3D echo. Regarding CT of the mitral valve, 25 (61%) patients had an undetectable calcium. There was no significant difference in CT calcium scores between severe and non-severe MS (74 ± 282 HU vs. 65 ± 210 HU, p = 0.9). MVA measurement by CMR is overestimated when compared to 3D echo. Additionally, mitral valve calcium score is not correlated to MS severity.

Reproducibility of transthoracic 3D echocardiography in the assessment of mitral valve area in patients with rheumatic mitral stenosis: real time versus ECG-gated 3D echocardiography

PURPOSE

To assess reproducibility of Real time 3D echocardiography (RT3D) and ECG-gated 3D echocardiography (EG3D) when measuring the mitral valve area (MVA) in rheumatic mitral stenosis (MS).

METHODS

MVA was assessed by three operators in 68 MS patients using RT3D and EG3D. Reproducibility of each technique was determined by calculating the standard error of measurements (SEM).

RESULTS

SEM was similar between RT3D and EG3D. MVA variability was of 0.4 cm² or 30% of any RT3D or EG3D measured MVA. The minimal change in MVA above which two measurements should be considered to differ significantly for the same operator was of 0.4 cm² for RT3D and 0.5 cm² for EG3D. For two different operators making successive measurements, the minimum significant change was of 0.5 cm² for RT3D and 0.6 cm² for EG3D. The minimum significant difference when switching from RT3D to EG3D or vice versa is of 0.6 cm². Low temporal resolution of 6 Hz has the least variability when using RT3D (0.19 cm² vs. 0.26 cm², p = 0.009) but significantly underestimated MVA (1.3 ± 0.4 cm² vs. 1.4 ± 0.4 cm², p < 10- 3) when compared to EG3D. MVA variability was significantly higher in mild MS when compared to severe MS whether it is RT3D (0.23 cm² vs. 0.18 cm², p = 0.02) or EG3D (0.27 cm² vs. 0.16 cm², p < 0.001).

CONCLUSION

RT3D and EG3D are equally reproducible in the assessment of MVA in patients with MS. Further measurements standardization is required to have a clinically acceptable estimations of the true 3D MVA and minimal detectable differences.

3D Echocardiography for Rheumatic Heart Disease Analysis: Ready for Prime Time

Rheumatic heart disease (RHD) remains to be a very important health issue worldwide, mainly in underdeveloped countries. It continues to be a leading cause of morbidity and mortality throughout developing countries. RHD is a delayed non-suppurative immunologically mediated inflammatory response to the throat infection caused by a hemolytic streptococcus from the A group (Streptococcus pyogenes). RHD keeps position 1 as the most common cardiovascular disease in young people aged <25 years considering all the continents. The disease can lead to valvular cardiac lesions as well as to carditis. Rheumatic fever valvular injuries lead most commonly to the fusion and thickening of the edges of the cusps and to the fusion, thickening, and shortening of the chordae and ultimately to calcification of the valves. Valvular commissures can also be deeply compromised, leading to severe stenosis. Atrial and ventricular remodeling is also common following rheumatic infection. Mixed valvular lesions are more common than isolated valvular disorders. Echocardiography is the most relevant imaging technique not only to provide diagnostic information but also to enable prognostic data. Further, it presents a very important role for the correction of complications after surgical repair of rheumatic heart valvulopathies. Three-dimensional (3D) echocardiography provides additional anatomical and morphofunctional information of utmost importance for patients presenting rheumatic valvopathies. Accordingly, three-dimensional echocardiography is ready for routine use in patients with RHD presenting with valvular abnormalities.

Transthoracic two-dimensional and three-dimensional echocardiography for the measurement of mitral valve area planimetry in English Bull Terriers with and without heart disease

INTRODUCTION

Mitral valve area (MVA) planimetry is used to diagnose and classify mitral stenosis (MS) in humans using two-dimensional and three-dimensional echocardiography (MVA_2D and MVA_3D). This study aimed to evaluate agreement, feasibility, and observer variability between MVA_2D and MVA_3D in English Bull Terriers (BT). Our hypotheses were (1) that the MVA of BT is generally smaller than that of breeds with similar body weight and (2) that these techniques could be used to diagnose MS in BTs.

ANIMALS

Twenty healthy BTs, 15 healthy Boxers, and 49 BTs with heart disease.

MATERIALS AND METHODS

A prospective diagnostic agreement study was conducted. All dogs underwent a thorough clinical examination, conventional transthoracic echocardiography, and three-dimensional echocardiography.

RESULTS

Bland-Altman plots (limits of agreement: 0.12-1.5) showed consistent bias and poor agreement between MVA_2D and MVA_3D. For the 69 BTs, MVA_3D (2.1 ± 0.50 cm²) measurements were significantly lower than MVA_2D measurements (2.9 ± 0.60 cm²), and healthy BTs had significantly lower MVA parameters than healthy Boxers (p < 0.001). Intraobserver and interobserver variability were excellent for both MVA_2D and MVA_3D (intraclass correlation coefficient >0.9). Six BTs were diagnosed with MS, with MVA_3D less than 1.8 cm² and a mean transmitral gradient (MTG) of more than 5 mmHg.

CONCLUSIONS

Both MVA_2D and MVA_3D are feasible, have low observer variability and can be used to diagnose MS in BTs. For assessing the narrowest orifice area, the preferred method is MVA_3D. The smaller MVA in BTs compared to Boxers may indicate some degree of MS.

Agreement between three-dimensional planimetry and mitral navigation method in the assessment of mitral valve area in rheumatic severe mitral stenosis

INTRODUCTION

Rheumatic heart disease predisposes to structural changes in the mitral valve including commissural fusion and calcification with subsequent narrowing of the mitral valve orifice resulting in rheumatic mitral stenosis (RMS). To define the best therapeutic strategy, an accurate measurement of mitral valve area (MVA) for RMS is of paramount importance. The propose of the present study was to assess the agreement between the mitral navigation method (MVN) and three-dimensional (3D) planimetry in the assessment of MVA in patients with RMS.

METHODS

Patients who were diagnosed with a different degree of mitral stenosis with the standard transthoracic echocardiography methods such as the pressure half time and planimetry underwent 3D transesophageal echocardiography (TEE) examination. 3D TEE zoom mitral valve planimetry was measured in the diastolic frame during the mitral valve's largest opening. By using MVN software of the Philips Q-Lab, MVA was measured at its maximum diastolic opening. Both 3D planimetry (3DPL) and MVN were measured at the mid diastole during the mitral valve's largest opening.

RESULTS

In this retrospective analysis, we examined consecutive 37 RMS patients (mean age 51.1 ± 11.6 years, 31 patients were female). MVA measured by the MVN method was found to be highly correlated with the 3D MVA measured by 3DPL (r = 0.937, p<.001).

CONCLUSIONS

Based on our results, we showed that the MVN method may be additionally used in detecting the severity of RMS.

Three-dimensional transesophageal echocardiography measurement of mitral valve area in patients with rheumatic mitral stenosis: multiplanar reconstruction or 3D direct planimetry?

3D direct planimetry is increasingly used in clinical practice as a rapid way to measure the mitral valve area (MVA) in patients with rheumatic mitral stenosis (MS) who underwent three-dimensional transesophageal echocardiography (3D-TEE). However, data on its accuracy and reliability are scarce. This study aimed to compare the MVA measurements obtained by 3D direct planimetry to the conventional technique multiplanar reconstruction (MPR) in MS patients using 3D-TEE. We retrospectively included 49 patients with rheumatic MS undergoing clinically-indicated 3D-TEE in the study. We determined the 3D direct planimetry measurements of MVA from the left atria aspect (MVA_LA) and the left ventricle aspect (MVA_LV), and compared those with the MPR method (MVA_MPR). We also assessed the major and minor diameters of the mitral valve orifice using MPR and 3D direct planimetry. We found an excellent agreement between the MVA measurements obtained by the MPR method and 3D direct planimetry (MVA_LA and MVA_LV) [intraclass correlation coefficients (ICC) = 0.951 and 0.950, respectively]. However, the MVA_MPR measurements were significantly larger than the MVA_LA and MVA_LV (p < 0.001; mean difference: 0.12 ± 0.15 cm² and 0.11 ± 0.16 cm², respectively).The inter-observer and intra-observer variability ICC were 0.875 and 0.856 for MVA_MPR, 0.982 and 0.984 for MVA_LA, and 0.988 and 0.986 for MVA_LV, respectively. The major diameter measured by MPR (1.90 ± 0.42 cm) was significantly larger than that obtained by 3D direct planimetry (1.72 ± 0.35 cm for the LA aspect, p < 0.001; 1.73 ± 0.36 cm for the LV aspect, p < 0.001). The minor diameter measured by MPR (0.96 ± 0.25 cm) did not differ from that derived by 3D direct planimetry (0.94 ± 0.25 cm for the LA aspect, p = 0.07; 0.95 ± 0.27 cm for the LV aspect, p = 0.32). 3D direct planimetry provides highly reproducible measurements of MVA and yields data in excellent agreement with those obtained by the MPR method. The discrepancy between the two techniques may be due to differences in major diameter measurements of the mitral valve orifice.

Meta-Analysis of the Incidence, Prevalence, and Correlates of Atrial Fibrillation in Rheumatic Heart Disease

Objective:

To estimate the incidence, prevalence, and correlates of atrial fibrillation (AF) in a global population with rheumatic heart disease (RHD).

Methods:

Bibliographic databases were searched to identify all published studies providing data on AF in patients with RHD. Random-effects meta-analysis method was used to pool estimates.

Results:

Eighty-three studies were included, reporting data from 75,637 participants with RHD in 42 countries. The global prevalence of AF in RHD was 32.8% (range: 4.3%–79.9%). It was higher in severe valvular disease (30.8% vs 20.7%, p = 0.009), in severe mitral valve disease compared to severe aortic disease (30.4% vs 6.3%, p = 0.038). The global cumulative incidence of AF in patients with RHD was 4.8%, 11.4%, 13.2%, and 30.8% at 1, 2, 5, and 10 years of follow-up, respectively. From comparison between patients with and without AF, AF was associated with increased age (mean difference [MD]: 9.5 years; 95% CI: 7.8–1.3), advanced heart failure (odds ratio [OR]: 4.4; 95% CI 2.1–9.3), tricuspid valve involvement (OR: 4.0; 95% CI: 3.0–5.3), history of thromboembolism (OR: 6.2; 95% CI: 3.4–11.4), highly sensitive C-reactive protein (MD: 5.5 mg/dL; 95% CI: 1.2–9.8), systolic pulmonary arterial pressure (MD: 3.6 mmHg; 95% CI: 0.8–6.3), right atrium pressure (MD: 1.5 mmHg; 95% CI: 1.0–2.0), and left atrium diameter (MD: 8.1 mm; 95% CI: 5.5–10.7).

Conclusions:

About one-third of patients with RHD have AF, with an incidence which almost triples every five years after diagnosis. Factors associated with AF include age, advanced heart failure, thromboembolism, and few cardiac hemodynamics parameters.

Targeting protein methylation: from chemical tools to precision medicines

The methylation of proteins is integral to the execution of many important biological functions, including cell signalling and transcriptional regulation. Protein methyltransferases (PMTs) are a large class of enzymes that carry out the addition of methyl marks to a broad range of substrates. PMTs are critical for normal cellular physiology and their dysregulation is frequently observed in human disease. As such, PMTs have emerged as promising therapeutic targets with several inhibitors now in clinical trials for oncology indications. The discovery of chemical inhibitors and antagonists of protein methylation signalling has also profoundly impacted our general understanding of PMT biology and pharmacology. In this review, we present general principles for drugging protein methyltransferases or their downstream effectors containing methyl-binding modules, as well as best-in-class examples of the compounds discovered and their impact both at the bench and in the clinic.

Rheumatic Mitral Valve Stenosis: Diagnosis and Treatment Options

PURPOSE OF REVIEW

This review provides an update on rheumatic mitral stenosis. Acute rheumatic fever (RF), the sequela of group A β-hemolytic streptococcal infection, is the major etiology for mitral stenosis (MS).

RECENT FINDINGS

While the incidence of acute RF in the Western world had substantially declined over the past five decades, this trend is reversing due to immigration from non-industrialized countries where rheumatic heart disease (RHD) is higher. Pre-procedural evaluation for treatment of MS using a multimodality approach with 2D and 3D transthoracic and transesophageal echo, stress echo, cardiac CT scanning, and cardiac MRI as well as hemodynamic assessment by cardiac catheterization is discussed. The current methods of percutaneous mitral balloon commissurotomy (PMBC) and surgery are also discussed. New data on long-term follow-up after PMBC is also presented. For severe rheumatic MS, medical therapy is ineffective and definitive therapy entails PMBC in patients with suitable morphological mitral valve (MV) characteristics, or surgery. As procedural outcomes depend heavily on appropriate case selection, definitive imaging and interpretation are crucial. It is also important to understand the indications as well as morphological MV characteristics to identify the appropriate treatment with PMBC or surgery.

Quantification of rheumatic mitral stenosis severity with three-dimensional vena contracta area

INTRODUCTION

Rheumatic mitral stenosis (MS) is an important health issue in developing countries. Assessment of the correct mitral valve area (MVA) is essential for the timing of intervention. Most of the parameters for the assessment of rheumatic MS are derived from Two-dimensional (2D) echocardiography. Three-dimensional (3D) echocardiography is commonly used in our daily practice at the present time. The aim of this study was to assess the value of 3D echocardiography mitral valve vena contracta area (VCA) in predicting the severity of Rheumatic MS by comparing 3D planimetry.

METHODS

The patients, who had been diagnosed as mild, moderate, and severe rheumatic MS with conventional methods (pressure half time, planimetry) by 2D transesophageal echocardiography (TEE)/ transthoracic echocardiography (TTE), underwent 3D TEE evaluation. Also, the patients who had an atrial fibrillation and more than moderate aortic regurgitation were included in the study. 3D TEE full volume mitral valve VCA was measured in end-diastole during its largest dimensions. 3D TEE full volume and 3D zoom MVA planimetry were measured at the end-diastole during the mitral valve`s largest opening.

RESULTS

We studied 40 patients (the mean age: 51.1 ± 11.6 years, 31 females) with rheumatic MS. 3D TEE VCA was found to be highly correlated with the 3D TEE MVA (r = 0.82, P < 0.001).

CONCLUSION

Our study findings provide evidence that 3D TEE mitral valve VCA can be additionally used in detecting the severity of rheumatic MS.

Impact of 3D echocardiography on grading of mitral stenosis and prediction of clinical events

Background

The mitral valve orifice area (MVOA) is difficult to assess accurately by 2D echocardiography because of geometric assumptions; therefore, 3D planimetry may offer advantages. We studied the differences in MVOA measurements between the most frequently used methods, to determine if 3D planimetry would result in the re-grading of severity in any cases, and whether it was a more accurate predictor of clinical outcomes.

Methods

This was a head-to-head comparison of the three most commonly used techniques to grade mitral stenosis (MS) by orifice area and to assess their impact on clinical outcomes. 2D measurements (pressure half-time (PHT), planimetry) and 3D planimetry were performed retrospectively on patients with at least mild MS. The clinical primary endpoint was defined as a composite of MV balloon valvotomy, mitral valve repair or replacement (MVR) and/or acute heart failure (HF) admissions.

Results

Forty-one consecutive patients were included; the majority were female (35; 85.4%), average age 55 (17) years. Mean and peak MV gradients were 9.4 (4) mmHg and 19 (6) mmHg, respectively. 2D and 3D measures of MVOA differed significantly; mean 2D planimetry MVOA was 1.28 (0.40) cm², mean 3D planimetry MVOA 1.15 (0.29) cm² (P = 0.003). Mean PHT MVOA was 1.43 (0.44) cm² (P = 0.046 and P < 0.001 in comparison to 2D and 3D planimetry methods, respectively). 3D planimetry reclassified 7 (17%) patients from mild-to-moderate MS, and 1 (2.4%) from moderate to severe. Overall, differences between the two methods were significant (X², P < 0.001). Only cases graded as severe by 3D predicted the primary outcome measure compared with mild or moderate cases (odds ratio 5.7).

Conclusion

3D planimetry in MS returns significantly smaller measurements, which in some cases results in the reclassification of severity. Routine use of 3D may significantly influence the management of MS, with a degree of prediction of clinical outcomes.