Impact of Net Atrioventricular Compliance on Mitral Valve Area Assessment-A Perspective Considering Three-Dimensional Mitral Valve Area by Transesophageal Echocardiography.

BACKGROUND: Net atrioventricular compliance (Cn) can affect the accuracy of mitral valve area (MVA) assessment. We assessed how different methods of MVA assessment are affected by Cn, and if patients with abnormal Cn may be identified by clinical and/or echocardiographic parameters. METHODS: We studied 244 patients with rheumatic MS. The concordance between mitral valve area (MVA) by 2D planimetry, pressure half-time (PHT), continuity equation (CE), Yeo's index, and 3-dimensional mitral valve area assessed by transesophageal echocardiography (TEE 3DMVA) in patients with normal and abnormal Cn (Cn ≤ 4 mL/mmHg) were evaluated in the 110 patients with both transesophageal echocardiogram (TEE) and transthoracic echocardiogram (TTE). Variables that were associated with abnormal Cn were validated in the remaining 134 patients with only TTE. RESULTS: Except for MVA by CE, concordance with TEE 3DMVA was poorer for all other methods of MVA assessment in patients with abnormal Cn. But, the difference in concordance was only statistically significant for MVA by PHT. Patients with MVA ≤ 1.5 cm2 by 2D planimetry and PHT ≤ 130 ms were likely to have an abnormal Cn. (specificity 98.5%). This finding was validated in the remaining 134 patients (specificity 93%). CONCLUSIONS: MVA assessment by PHT is significantly affected by Cn. Abnormal Cn should be suspected when 2D planimetry MVA is ≤1.5 cm2 together with an inappropriately short PHT that is ≤130 ms. In this scenario, MVA by PHT is inaccurate.

Validation of Yeo's index in assessing severity of rheumatic mitral stenosis in mixed valve lesions.

Introduction: Yeo's Index, product of the mitral leaflet separation index and dimensionless index, is a novel measure of the severity of rheumatic mitral stenosis (MS). We assess Yeo's index in patients with rheumatic MS with or without mixed valve disease. Methods: In a retrospective cohort study, Yeo's index was measured in 237 cases of rheumatic MS - 124 in a transthoracic echocardiography validation cohort using mitral valve area (MVA) by pressure half-time and planimetry as comparator and 113 in a transesophageal echocardiography (TEE) validation cohort using TEE three-dimensional MVA as comparator. Patients were considered to have mixed valve disease if they had MS and concomitant mitral regurgitation or aortic valve disease. Results: There were 113 patients with isolated MS and 124 patients with mixed valve disease. Overall, Yeo's index ≤ 0.26 cm showed 93.0 % sensitivity and 87.5 % specificity for identifying severe MS (MVA ≤ 1.5 cm2). In isolated MS, Yeo's index ≤ 0.26 cm showed sensitivity of 94.6 % and specificity of 90.0 % for identifying severe MS, while in mixed valve disease sensitivity was 90.6 % and specificity 86.7 %. Overall, Yeo's index ≤ 0.15 cm showed 83.6 % sensitivity and 94.3 % specificity for very severe MS (MVA ≤ 1.0 cm2). In isolated MS, the threshold of ≤0.15 cm showed sensitivity of 84.4 % and specificity of 92.6 % for very severe MS, while in mixed valve disease sensitivity was 81.3 % and specificity 95.3 %. The presence of atrial fibrillation did not influence the performance of Yeo's index. Conclusion: Yeo's Index accurately differentiates severity of rheumatic MS with or without mixed valve disease.

Combining 2D Planimetry and Yeo's Index Can Help Accurately Identify Patients with Severe Rheumatic Mitral Stenosis-A Perspective from a 3D Assessment Using Transoesophageal Echocardiography.

BACKGROUND: Yeo's index is a novel measure of the severity of rheumatic mitral valve stenosis (MS). It is derived from the product of the mitral leaflet separation index and dimensionless index. This study aims to validate Yeo's index using a transesophageal echocardiogram (TEE) three-dimensional (3D) mitral valve area (MVA) as a comparator and to compare the concordance of existing echocardiographic measures of the MVA with TEE 3DMVA. METHODS AND RESULTS: We studied 111 patients with rheumatic MS who underwent both transthoracic echocardiography (TTE) and a TEE assessment of MS severity. Yeo's index, the MVA determined by 2D planimetry, pressure half-time (PHT) and continuity equation (CE) measured on TTE were compared with the TEE 3DMVA. With a linear correlation, Yeo's index showed the best correlation with TEE 3DMVA (r2 = 0.775), followed by 2D planimetry (r2 = 0.687), CE (r2 = 0.598) and PHT (r2 = 0.363). Using TEE 3DMVA as comparator, Yeo's index (ρc = 0.739) demonstrated the best concordance, followed by 2D planimetry (ρc = 0.632), CE (ρc = 0.464) and PHT (ρc = 0.366). When both Yeo's index and 2D planimetry suggested significant MS, the positive predictive value was high (an AUC of 0.966 and a PPV of 100.00% for severe MS, and an AUC of 0.864 and a PPV of 85.71% for very severe MS). When both measures suggested the absence of significant MS, the negative predictive value was also high (an AUC of 0.940 and an NPV of 88.90% for severe MS, and an AUC of 0.831 and an NPV of 88.71% for very severe MS). CONCLUSIONS: Yeo's index performed well in identifying severe MS when compared with TEE 3DMVA and may be a useful adjunct to existing methods of measuring MS severity. Combining it with 2D planimetry could further enhance its accuracy.

Yeo's index: A novel index that combines anatomic and haemodynamic assessment of the severity of mitral stenosis.

BACKGROUND: A mitral leaflet separation index (MLSI), measuring the anatomical separation of the mitral valve (MV) leaflet tips in diastole, was previously described as an accurate method of assessing mitral stenosis (MS). We propose a novel modification of the MLSI by including a hemodynamic assessment which we term Yeo's index that may improve its diagnostic performance. METHODS AND RESULTS: We retrospectively studied 174 patients with varying severity of MS without significant mitral regurgitation, aortic valve disease or ventricular septal defect. MLSI was measured in 2 orthogonal views on transthoracic echocardiography as previously described. MV dimensionless index (DI) was calculated by dividing the left ventricular outflow tract pulsed-wave Doppler time velocity integral (TVI) by the MV continuous-wave Doppler TVI. We defined Yeo's index as the product of MLSI and DI. With linear correlation, Yeo's index demonstrated good correlation against MVA by planimetry (r = 0.728), pressure half-time (r = 0.677), and continuity equation (r = 0.829), with improved performance over the MLSI. Using ROC analysis, Yeo's index demonstrated good ability to correctly classify MS as severe (MVA ≤1.5cm2) (AUC 0.874, 95% CI 0.816-0.920). Yeo's index ≤0.260 cm correctly classified severe MS with sensitivity of 82% and specificity of 80%. Presence of AF did not affect the performance of Yeo's index. Yeo's index ≤0.147 cm also identified very severe MS (MVA ≤ 1.0 cm2) with specificity of 94% and sensitivity of 78%. CONCLUSION: Yeo's index performed well in identifying severe MS and may be a useful adjunct to existing measures of MS severity.

Prognostic value of left atrial volume index in degenerative mitral stenosis.

PURPOSE: Degenerative mitral stenosis (DMS) is associated with a poor prognosis. Although mean transmitral gradient (TMG) has shown a good correlation with outcome, little is known about the association between other echocardiographic parameters and prognosis in patients with DMS. The current study aimed to evaluate the prognostic value of left atrial volume index (LAVI) in patients with DMS. METHODS: A total of 155 patients with DMS (72[63-80] years, 67% female) were included. The population was divided according to LAVI: normal-sized LAVI (LAVI ≤ 34 ml/m2); and enlarged LAVI (> 34 ml/m2). RESULTS: Patients with enlarged LAVI had a higher left ventricular mass index (120[96-146] vs. 91[70-112] g/m2 p < 0.001), as well as a higher prevalence of significant mitral regurgitation and severe aortic stenosis (23% vs. 10% p = 0.046 and 38% vs. 15% p=0.001, respectively) compared to patients with normal-sized LAVI. During a median follow-up of 25 months, 56 (36%) patients died. Patients with enlarged LAVI had worse prognosis compared to patients with normal-sized LAVI (p = 0.026). In multivariable Cox regression model, an enlarged LAVI was independently associated with all-cause mortality (HR 2.009, 95% CI 1.040 to 3.880, P = 0.038). CONCLUSION: An enlarged LAVI (> 34 ml/m2) is significantly associated with excess mortality in patients with DMS. After adjusting for potential confounders, an enlarged LAVI was the only parameter that remained independently associated with prognosis.

Clinical and echocardiographic characteristics associated with the development of infective endocarditis in patients with significant mitral stenosis.

BACKGROUND: Infective endocarditis (IE) confers significant mortality and morbidity in patients with underlying mitral stenosis (MS), with both diseased native valves and after valvular procedures. PURPOSE: We examined the clinical and echocardiographic parameters in association with the development of IE on patients with significant MS. METHODS: A total of 478 consecutive patients with index echocardiographic diagnosis of significant mitral stenosis (mitral valve area <1.5 cm2 ) were included. Patients were grouped into those with or without IE on at least 5 years of follow-up. Baseline clinical, echocardiographic profile and clinical outcomes were compared. RESULTS: IE was observed in 4.4% (n = 21) of the cohort. These patients were younger (45.3 ± 14.6 vs. 53.2 ± 15.5 years, p = 0.022) at the time of MS diagnosis. NT-proBNP was higher in patients who developed IE (13529 ± 12230 vs. 4381 ± 5875 pg/ml, p < 0.001), with larger left atrial diameter (54.4 ± 10.1 vs. 49.9 ± 9.5 mm, p = 0.040) and elevated pulmonary artery systolic pressure (PASP, 62.3 ± 17.2 vs. 47.2 ± 16.5 mmHg, p = 0.026). There was no significant difference in terms of MS severity, other concomitant valvulopathies, or etiology (rheumatic or degenerative) of MS. Patients who smoked had higher incidence of IE (33.3% vs. 14.2%, log-rank 7.27, p = 0.007). After adjusting for age, valve procedure and PASP, patients who smoked remained at elevated risk of IE (adjusted hazards ratio 2.99, 95% confidence interval 1.18-7.56, p = 0.021). CONCLUSION: IE occurs in a proportion of patients with MS. Smoking, younger age of diagnosis of MS as well as dilated left atria with elevated PASP may be associated with an elevated risk of this complication.