Inaccuracy of mitral pressure half-time immediately after percutaneous mitral valvotomy. Dependence on transmitral gradient and left atrial and ventricular compliance

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.

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.

Multimodality imaging for patient selection, procedural guidance, and follow-up of transcatheter interventions for structural heart disease: a consensus document of the EACVI Task Force on Interventional Cardiovascular Imaging: part 1: access routes, transcatheter aortic valve implantation, and transcatheter mitral valve interventions

Transcatheter therapies for the treatment of structural heart diseases (SHD) have expanded dramatically over the last years, thanks to the developments and improvements of devices and imaging techniques, along with the increasing expertise of operators. Imaging, in particular echocardiography, is pivotal during patient selection, procedural monitoring, and follow-up. The imaging assessment of patients undergoing transcatheter interventions places demands on imagers that differ from those of the routine evaluation of patients with SHD, and there is a need for specific expertise for those working in the cath lab. In the context of the current rapid developments and growing use of SHD therapies, this document intends to update the previous consensus document and address new advancements in interventional imaging for access routes and treatment of patients with aortic stenosis and regurgitation, and mitral stenosis and regurgitation.

Impact of assuming a circular orifice on flow error through elliptical regurgitant orifices: computational fluid dynamics and in vitro analysis of proximal flow convergence

Grounded in hydrodynamic theory, proximal isovelocity surface area (PISA) is a simplistic and practical technique widely used to quantify valvular regurgitation flow. PISA provides a relatively reasonable, though slightly underestimated flow rate for circular orifices. However, for elliptical orifices frequently seen in functional mitral regurgitation, PISA underestimates the flow rate. Based on data obtained with computational fluid dynamics (CFD) and in vitro experiments using systematically varied orifice parameters, we hypothesized that flow rate underestimation for elliptical orifices by PISA is predictable and within a clinically acceptable range. We performed 45 CFD simulations with varying orifice areas 0.1, 0.3 and 0.5 cm², orifice aspect ratios 1:1, 2:1, 3:1, 5:1, and 10:1, and peak velocities (V_max) 400, 500 and 600 cm/s. The ratio of computed effective regurgitant orifice area to true effective area (EROA_C/EROA) against the ratio of aliasing velocity to peak velocity (V_A/V_max) was analyzed for orifice shape impact. Validation was conducted with in vitro imaging in round and 3:1 elliptical orifices. Plotting EROA_C/EROA against V_A/V_max revealed marginal flow underestimation with 2:1 and 3:1 elliptical axis ratios against a circular orifice (< 10% for 8% V_A/V_max), rising to ≤ 35% for 10:1 ratio. In vitro modeling confirmed CFD findings; there was a 8.3% elliptical EROA underestimation compared to the circular orifice estimate. PISA quantification for regurgitant flow through elliptical orifices produces predictable, but generally small, underestimation deemed clinically acceptable for most regurgitant orifices.

Recommendations for the Use of Echocardiography in the Evaluation of Rheumatic Heart Disease: A Report from the American Society of Echocardiography

Acute rheumatic fever and its chronic sequela, rheumatic heart disease (RHD), pose major health problems globally, and remain the most common cardiovascular disease in children and young people worldwide. Echocardiography is the most important diagnostic tool in recognizing this preventable and treatable disease and plays an invaluable role in detecting the presence of subclinical disease needing prompt therapy or follow-up assessment. This document provides recommendations for the comprehensive use of echocardiography in the diagnosis and therapeutic intervention of RHD. Echocardiographic diagnosis of RHD is made when typical findings of valvular and subvalvular abnormalities are seen, including commissural fusion, leaflet thickening, and restricted leaflet mobility, with varying degrees of calcification. The mitral valve is predominantly affected, most often leading to mitral stenosis. Mixed valve disease and associated cardiopulmonary pathology are common. The severity of valvular lesions and hemodynamic effects on the cardiac chambers and pulmonary artery pressures should be rigorously examined. It is essential to take advantage of all available modalities of echocardiography to obtain accurate anatomic and hemodynamic details of the affected valve lesion(s) for diagnostic and strategic pre-treatment planning. Intraprocedural echocardiographic guidance is critical during catheter-based or surgical treatment of RHD, as is echocardiographic surveillance for post-intervention complications or disease progression. The role of echocardiography is indispensable in the entire spectrum of RHD management.

Advances in Rheumatic Mitral Stenosis: Echocardiographic, Pathophysiologic, and Hemodynamic Considerations

Echocardiography is the primary imaging modality used in patients with mitral stenosis. Doppler-derived measurements of mitral pressure half-time are commonly used to calculate mitral valve area, but a number of hemodynamic confounders associated with advanced age limit its utility. Planimetry remains the gold standard for determining mitral valve area and may be performed using two- or three-dimensional imaging. Although the Wilkins score has been used for >30 years to predict balloon mitral valvuloplasty outcomes, newer scoring systems have been proposed to improve predictive accuracy. Some patients undergoing technically successful balloon mitral valvuloplasty may not have satisfactory clinical outcomes. These individuals may be identified by the presence of reduced net atrioventricular compliance, which can be measured echocardiographically. Exercise testing may be useful in patients with mitral stenosis whose symptomatic status is incongruous their mitral valve area. Last, reduced left atrial systolic strain, an indicator of poor left atrial compliance, has been shown to reliably predict adverse outcomes in patients with mitral stenosis. The author discusses the hemodynamics and path ophysiology of mitral stenosis and reviews current and emerging roles of echocardiography in its evaluation.

The most influential papers in mitral valve surgery; a bibliometric analysis

This study is an analysis of the 100 most cited articles in mitral valve surgery. A bibliometric analysis is a tool to evaluate research performance in a given field. It uses the number of times a publication is cited by others as a proxy marker of its impact. The most cited paper Carpentier et al. discusses mitral valve repair in terms of restoring the geometry of the entire valve rather than simply narrowing the annulus (Carpentier, J Thorac Cardiovasc Surg 86:23–37, 1983). The first successful mitral valve repair was performed by Elliot Cutler at Brigham and Women’s Hospital in 1923 (Cohn et al., Ann Cardiothorac Surg 4:315, 2015). More recently percutaneous and minimally invasive techniques that were originally designed as an option for high risk patients are being trialled in other patient groups (Hajar, Heart Views 19:160–3, 2018). Comparison of percutaneous method with open repair represents an expanding area of research (Hajar, Heart Views 19:160–3, 2018). This study will analyse the top 100 cited papers relevant to mitral valve surgery, identifying the most influential papers that guide current management, the institutions that produce them and the authors involved.

A Novel 3-Dimensional Approach for the Echocardiographic Evaluation of Mitral Valve Area After Repair for Degenerative Disease

BACKGROUND

Currently available 2-dimensional (2D) echocardiographic methods for accurately assessing the mitral valve orifice area (MVA) after mitral valve repair (MVr) are limited due to its complex 3-dimensional (3D) geometry. We compared repaired MVAs obtained with commonly used 2D and 3D echocardiographic methods to a 3D orifice area (3DOA), which is a novel echocardiographic measurement and independent of geometric assumptions.

METHODS

Intraoperative 2D and 3D transesophageal echocardiography (TEE) images from 20 adult cardiac surgery patients who underwent MVr for mitral regurgitation obtained immediately after repair were retrospectively reviewed. MVAs obtained by pressure half-time (PHT), 2D planimetry (2DP), and 3D planimetry (3DP) were compared to those derived by 3DOA.

RESULTS

MVAs (mean value ± standard deviation [SD]) after MVr were obtained by PHT (3 ± 0.6 cm), 2DP (3.58 ± 0.75 cm), 3D planimetry (3DP; 2.78 ± 0.74 cm), and 3DOA (2.32 ± 0.76 cm). MVAs obtained by the 3DOA method were significantly smaller compared to those obtained by PHT (mean difference, 0.68 cm; P = .0003), 2DP (mean difference, 1.26 cm; P < .0001), and 3DP (mean difference, 0.46 cm; P = .003). In addition, MVA defined as an area ≤1.5 cm was identified by 3DOA in 2 patients and by 3DP in 1 patient.

CONCLUSIONS

Post-MVr MVAs obtained using the novel 3DOA method were significantly smaller than those obtained by conventional echocardiographic methods and may be consistent with a higher incidence of MVA reduction when compared to 2D techniques. Further studies are still needed to establish the clinical significance of 3D echocardiographic techniques used to measure MVA after MVr.

Comparison of 2D vena contracta area with 3D planimetric mitral valve area in rheumatoid mitral valve disease

Rheumatoid valve disease is a general health problem of developing countries, and it mainly affects after the age of 40. Assessment of the correct mitral valve area (MVA) is important for the treatment of rheumatoid valve disease. However, there are contradictions between the three-dimensional (3D) and two-dimensional (2D) methods. A measurement with 3D echocardiography is a more accurate method to measure the MVA. However, in centers without 3D echocardiography, there are some difficulties in the accurate measurement of the MVA. The aim of this study was to assess the value of 2D transesophageal echocardiography (TEE) mitral valve vena contracta area (VCA) in predicting the severity of rheumatoid mitral stenosis (RMS) by comparing 3D planimetry. A total of 24 patients (10 females and 14 males) who were diagnosed with mild/moderate/severe RMS with using pressure half time, mean transmitral gradient, and planimetry methods were included in this study. 3D images were acquired using the 3D zoom and full volume. 2D TEE VCA was measured at an angle of 140° and 60°, which was perpendicular to the former, with color Doppler and the VCA was measured with an ellipsoid area using mathematical formula. There was statistically significant relationship between the measurements of 2D VCA and 3D zoom mode MVA planimetry and MVA full measurements (MVA full volume) (p < 0.01). Calculation of the valvular area after measuring the mitral valve VCA with 2D TEE is a reliable method that is usable in centers without 3D echocardiography.

Impact of Mitral Stenosis on Survival in Patients Undergoing Isolated Transcatheter Aortic Valve Implantation

This study was performed to investigate the prevalence and impact on survival of baseline mitral stenosis (MS) in patients who underwent transcatheter aortic valve implantation (TAVI) due to the presence of severe symptomatic aortic stenosis. This retrospective study included 928 consecutive patients with severe, symptomatic aortic stenosis who underwent TAVI in 2 institutions, from January 2012 to August 2016. Mean follow-up was 40.8 ± 13.9 months. Based on the mean mitral gradient (MMG) at baseline, 3 groups were identified: MMG <5 mm Hg (n = 737, 81.7%); MMG ≥5 and <10 mm Hg (n = 147, 16.3%); MMG ≥10 mm Hg (n = 17, 1.9%). These latter were more frequently women, with a smaller body surface area, a higher prevalence of atrial fibrillation, chronic obstructive pulmonary disease, and previous history of coronary-artery bypass graft/percutaneous coronary intervention. At baseline, patients with MMG ≥10 mm Hg compared with ≥5 and <10 mm Hg and <5 mm Hg patients had a lower mitral valve area (2.4 ± 0.94 vs 2.1 ± 0.86 vs 1.5 ± 0.44 cm²), a lower prevalence of MR ≥2+ (5.9% vs 28.6% and 15.6%, p <0.0001), a higher prevalence of severe mitral annular calcium (70.6% vs 45.6% and 13.0%, p <0.0001) and a higher systolic pulmonary arterial pressure (50.6 ± 12.1 vs 47.2 ± 14.5 and 41.6 ± 14.4, p <0.0001). Despite the low prevalence of MMG ≥10 mm Hg, these patients had higher 5-year mortality compared with the other groups (adjusted hazard ratio 2.91, 95% confidence interval 1.17 to 7.20, p = 0.02). In conclusion, severe calcific MS is uncommon in patients who underwent TAVI. Its presence is associated with higher long-term mortality whereas moderate MS is not.

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.

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.

Impact of left atrial compliance improvement on functional status after percutaneous mitral valvuloplasty

BACKGROUND

Conventional hemodynamic parameters may not accurately predict symptomatic improvement after percutaneous mitral valvuloplasty (PMV). Changes in left heart chamber compliance following adequate relief o0066 mitral stenosis (MS) may be useful in determining functional capacity after PMV. This study aims to determine the acute effects of PMV on compliance of the left heart and whether its changes relate to the patient's functional capacity.

METHODS

One-hundred thirty-seven patients with severe MS undergoing PMV were enrolled. Left atrial (C_a ) and left ventricular (C_v ) compliance were invasively estimated and net atrioventricular compliance (C_av ) was calculated before and immediately after the procedure. B-type natriuretic peptide (BNP) levels were obtained before and 24 hr after the procedure. The primary endpoint was functional status at 6-month follow-up, and the secondary endpoint was a composite of death, mitral valve (MV) replacement, repeat PMV, new onset of atrial fibrillation, or stroke in patients in whom PMV was successful.

RESULTS

The mean age was 43 ± 12 years, and 119 patients were female (87%). After PMV, C_a and C_av improved significantly from 5.3 [IQR 3.2-8.2] mL/mmHg to 8.7 [5.3-19.2] mL/mmHg (P < 0.001) and 2.2 [1.6-3.4] to 2.8 [2.1-4.1] mL/mmHg (P < 0.001), respectively, whereas C_v did not change (4.6 [3.2-6.8] to 4.4 [3.1-5.6]; P = 0.637). Plasma BNP levels significantly decreased after PMV, with no correlation between its variation and changes in left chamber compliance. At 6-month follow-up, NYHA functional class remained unchanged in 32 patients (23%). By multivariable analyses, changes in C_a immediately after PMV (adjusted OR 1.42; 95% CI 95% 1.02 to 1.97; P = 0.037) and younger age (adjusted OR 0.95; CI 95% 0.92-0.98; P = 0.004), predicted improvement in functional capacity at 6-month follow-up, independent of postprocedural data. The secondary endpoint were predicted by post-PMV mean gradient (adjusted HR 1.363; 95% CI 95% 1.027-1.809; P = 0.032), and lack of functional improvement at 6-month follow-up (adjusted HR 4.959; 95% 1.708-14.403; P = 0.003).

CONCLUSIONS

C_a and C_av increase significantly after PMV with no change in C_v . The improvement of C_a is an important predictor of functional status at 6-month follow up, independently of other hemodynamic data. Postprocedural mean gradient and lack of short-term symptomatic improvement were predictors of adverse outcome.

Percutaneous Balloon Mitral Valvuloplasty: Echocardiographic Eligibility and Procedural Guidance

Rheumatic mitral stenosis remains a common disease in the developing world. Percutaneous mitral balloon valvuloplasty is an important therapy for rheumatic mitral stenosis. Echocardiography plays a critical role in the diagnosis of rheumatic mitral stenosis and the assessment of suitability for and guidance of percutaneous mitral valvuloplasty.

Left atrial compliance: an overlooked predictor of clinical outcome in patients with mitral stenosis or atrial fibrillation undergoing invasive management

In the assessment of cardiovascular disease, the clinical significance of left atrial (LA) pressure-volume relations has largely been overlooked in contrast to left ventricular (LV) compliance. However, LA compliance has recently gained more attention. Net atrioventricular compliance (Cn), a joint measure of LA and LV compliance, can be calculated non-invasively by a previously validated method using parameters from standard echocardiography. Compliance measurement may be of relevance in selected clinical settings. First, subjects with low Cn are more likely to have their mitral valve area overestimated by the traditional mitral pressure half-time method. Consequently, low Cn in mitral stenosis, usually resulting from reduced LA compliance, can be mistaken for mild mitral stenosis. Second, low Cn independently predicted pulmonary hypertension and disease progression in medically treated mitral stenosis, and late cardiovascular complications after successful percutaneous mitral valvuloplasty. Decreased LA compliance also accounts for stiff LA syndrome, a rare complication of radiofrequency catheter ablation for atrial fibrillation, manifesting as otherwise unexplained heart failure with elevated LA pressure and pulmonary hypertension. Finally, depressed pre-ablation LA stiffness index, i.e. the ratio of the change in LA pressure to the corresponding change in LA volume during passive LA filling, was an independent predictor of arrhythmia recurrence. Thus, LA stiffening translates into adverse clinical outcomes in patients with mitral stenosis or atrial fibrillation undergoing interventional procedures. Whether reduced LA compliance after LA appendage occlusion can result in the LA stiff syndrome, has not been reported so far.

Net atrioventricular compliance is an independent predictor of cardiovascular death in mitral stenosis

OBJECTIVES

Rheumatic mitral stenosis (MS) is a progressive disease, and risk of death may persist despite relief of the obstruction. Net atrioventricular compliance (C_n) modulates the overall haemodynamic burden of the MS and may be useful in predicting cardiovascular death after percutaneous mitral valvuloplasty (PMV).

METHODS

A total of 427 patients (mean age 50±16 years, 84% female) with severe MS undergoing PMV were enrolled. Doppler-derived C_n was estimated at baseline using a previously validated equation. The primary endpoint was late cardiovascular death, and the secondary endpoint was a composite of all-cause mortality, mitral valve (MV) replacement or repeat PMV over a median follow-up of 31 months (IQR: 7.8-49.2 months).

RESULTS

At baseline, 209 patients (49%) were in New York Heart Association (NYHA) functional class III or IV. During follow-up, 49 patients died (41 cardiovascular deaths), 50 underwent MV replacement and 12 required repeat PMV, with an overall incidence of cardiac mortality and adverse events of 4.1 deaths and 11.1 events per 100 patient-years, respectively. Low baseline C_n was a strong predictor of both cardiac death (adjusted HR 0.70, 95% CI 0.49 to 0.86) and composite endpoint (adjusted HR 0.81, 95% CI 0.67 to 0.91) after adjusting for clinical factors, baseline pulmonary artery pressure, tricuspid regurgitation severity, right ventricular function and immediate procedural haemodynamic data. The inclusion of C_n in a model with conventional parameters resulted in improvement in 5-year cardiovascular mortality risk prediction.

CONCLUSIONS

Baseline C_n is a strong predictor of cardiovascular death in patients with MS undergoing PMV, independent of other prognostic markers of decreased survival in MS, including baseline patient characteristics and postprocedural data. C_n assessment therefore has potential value in evaluation of cardiovascular mortality risk in the setting of MS.

The impact of cardiac rhythm on the mitral valve area and gradient in patients with mitral stenosis

OBJECTIVE

The aim of this study was to evaluate the effect of cardiac rhythm on the echocardiographic mitral valve area (MVA) and transmitral gradient calculation in relation to net atrioventricular compliance (Cn).

METHODS

Patients (n=22) with mild or moderate pure rheumatic mitral stenosis (MS) (MVA <2 cm2 and MVA >1 cm2) and atrial fibrillation (AF) were evaluated. All patients underwent transthoracic electrical DC cardioversion under amiodarone treatment. Nineteen of the 22 patients were successfully converted to sinus rhythm (SR). The patients were evaluated with transthoracic echocardiography before and two to three days after DC cardioversion. In order to deal with variable R-R intervals, the measurements were averaged on five to eight consecutive beats in AF. Cn was calculated with a previously validated equation [Cn (mL/mm Hg)=1.270 x MVA/E-wave downslope]. The Cn difference between AF and SR was calculated as follows: [(AF Cn-SR Cn)/AF Cn] x 100. The percentage gradient (mean or maximal) difference between AF and SR was calculated as follows: [AF gradient (mean or maximal) - SR gradient (mean or maximal)]/[AF gradient (mean or maximal)] x 100.

RESULTS

The MVA was lower (MVA planimetric; 1.62±0.29 vs. 1.54±0.27; p=.003, MVA PHT; 1.66±0.30 vs. 1.59±0.26; p=0.01) but transmitral gradient (mean gradient; 6.49±2.51 vs. 8.89±3.52; p=0.001, maximal gradient: 16.94±5.11 vs. 18.57±4.54; p=0.01) and Cn values (5.37±0.77 vs. 6.26±0.64; p<0.001) were higher in the AF than SR. There was a significant correlation between Cn difference and transmitral gradient difference (mean and maximal) (Cn difference-mean gradient difference; r=0.46; p=0.05; Cn difference-maximal gradient difference; r=0.72; p=0.001).

CONCLUSION

Cardiac rhythm has a significant impact on echocardiographic evaluation of MVA, transmitral gradient, and Cn in patients with MS.

Three-dimensional proximal flow convergence automatic calculation for determining mitral valve area in rheumatic mitral stenosis

PURPOSE

Management of patients with mitral stenosis (MS) depends heavily on the accurate quantification of mitral valve area (MVA) using echocardiography. All currently used two-dimensional (2D) methods have limitations. Estimation of MVA using the proximal isovelocity surface area (PISA) method with real time three-dimensional (3D) echocardiography may circumvent those limitations. We aimed to evaluate the accuracy of 3D direct measurement of PISA in the estimation of MVA.

METHODS

Twenty-seven consecutive patients (median age of 63 years; 77.8% females) with rheumatic MS were prospectively studied. Transthoracic and transesophageal echocardiography with 2D and 3D acquisitions were performed on the same day. The reference method for MVA quantification was valve planimetry after 3D-volume multiplanar reconstruction. A semi-automated software was used to calculate the 3D flow convergence volume.

RESULTS

Compared to MVA estimation using 3D planimetry, 3D PISA showed the best correlation (rho=0.78, P<.0001), followed by pressure half-time (PHT: rho=0.66, P<.001), continuity equation (CE: rho=0.61, P=.003), and 2D PISA (rho=0.26, P=.203). Bland-Altman analysis revealed a good agreement for MVA estimation with 3D PISA (mean difference -0.03 cm² ; limits of agreement (LOA) -0.40-0.35), in contrast to wider LOA for 2D methods: CE (mean difference 0.02 cm² , LOA -0.56-0.60); PHT (mean difference 0.31 cm² , LOA -0.32-0.95); 2D PISA (mean difference -0.03 cm² , LOA -0.92-0.86).

CONCLUSIONS

MVA estimation using 3D PISA was feasible and more accurate than 2D methods. Its introduction in daily clinical practice seems possible and may overcome technical limitations of 2D methods.

Mitral valve resistance determines hemodynamic consequences of severe rheumatic mitral stenosis and immediate outcomes of percutaneous valvuloplasty

INTRODUCTION

The mitral valve area (MVA) poorly reflects the hemodynamic status of (MS). In this study, we compared the MVA with mitral valve resistance (MVR) with regard to the determination of hemodynamic consequences of MS and the immediate outcomes of percutaneous balloon mitral valvuloplasty (PBMV).

METHODS

In a prospective study, 36 patients with severe rheumatic MS with left ventricular ejection fraction (LVEF) >50% were evaluated. They underwent transthoracic echocardiography (TTE) and catheterization. The MVA was measured by two-dimensional planimetry and pressure half-time (PHT), and the MVR was calculated using the equation: 1333 × transmitral pressure gradient mean transmitral diastolic flow rate.

RESULTS

The patients' mean age was 47.8±10.5 years. MVR ≥140.6 dynes·s/cm⁵ detected systolic pulmonary arterial pressure (sPAP) >55 mm Hg with a sensitivity of 100% and a specificity of 74%. The sensitivity and specificity of MVA<0.75 cm² to discriminate elevated sPAP were 81% and 89%, respectively. PHT ≥323.5 mseconds had a sensitivity of 78% and a specificity of 96% to detect an elevated sPAP. To predict a successful PBMV, preprocedural MVR ≥106.1 dynes·s/cm⁵ had a sensitivity of 100% and a specificity of 67% (area under the curve [AUC]=0.763; 95% confidence interval [CI]=0.520-1.006; P=.034); preprocedural MVA <0.95 cm² had a sensitivity of 78% and a specificity of 73% (AUC=0.730; 95% CI=0.503-0.956; P=.065); and preprocedural PHT ≥210.5 mseconds had a sensitivity of 73% and a specificity of 78% (AUC=0.707; 95% CI=0.474-0.941; P=.095).

CONCLUSIONS

MVR seems to be more accurate than MVA in determining the hemodynamic consequences of severe MS as determined by sPAP. In addition, preprocedural MVR detected successful PBMVs.

Immediate and mid-term result of restrictive mitral annuloplasty using a small semi-rigid ring

OBJECTIVE

Though annuloplasty using a properly sized ring has been advocated in degenerative mitral regurgitation, restrictive annuloplasty using a down-sized ring is widely used in ischemic mitral regurgitation. We investigated the outcome of restrictive annuloplasty using a small (24- or 26-mm) ring in mitral regurgitation irrespective of the etiology.

METHODS

Nineteen patients underwent a restrictive annuloplasty using a 24-mm (n = 8) or 26-mm (n = 11) semi-rigid ring. The etiology included degenerative in 13 patients, ischemic in 3, endocarditis in 2, and congenital in 1. Body surface area of the patients implanted with the 24-mm ring was 1.40 ± 0.16 and 1.60 ± 0.18 m(2) for the 26-mm ring. Fifteen patients had 3+ or 4+ mitral regurgitation preoperatively.

RESULTS

Two patients were converted to valve replacement for residual mitral regurgitation during the operation. One operative mortality associated with infection was observed. Echocardiogram at 29.4 ± 14.2 months postoperatively demonstrated mitral valve area of 2.0 ± 0.6 cm(2) for 24-mm ring and 2.2 ± 0.5 cm(2) for 26-mm ring with indexed mitral valve area of 1.4 ± 0.4 cm(2)/m(2) for both groups, and no mitral regurgitation more than 2+. Transmitral mean pressure gradient on rest was 4.7 ± 2.1 mmHg at last follow up. New York Heart Association class improved from 2.2 ± 0.7 to 1.2 ± 0.2 after the operation. No late death or reoperation was observed during the follow-up of 31.0 ± 15.0 months.

CONCLUSIONS

Restrictive mitral annuloplasty using a small ring provided acceptable early and midterm results in patients with body surface area around 1.5 cm(2) without Barlow pathology. Restrictive annuloplasty may be another technical aspect to avoid valve replacement.

Current diagnostic and treatment strategies for Lutembacher syndrome: the pivotal role of echocardiography

Lutembacher syndrome (LS) is a rare cardiac abnormality characterized by any combination of a congenital or iatrogenic atrial septal defect (ASD) and a congenital or acquired mitral stenosis (MS). Clinical features and hemodynamic effects of LS depend on the balance of effects of the MS and the ASD. Prognosis is influenced by several factors [pulmonary vascular resistance, right ventricle (RV) compliance, size of ASD and MS severity] but the occurrence of secondary pulmonary hypertension and congestive heart failure is commonly associated with poor outcome. Echocardiography remains the gold standard for diagnosis and evaluation of LS. Timely diagnosis is critical for modifying the natural course, by allowing patients to benefit from currently available percutaneous trans-catheter therapies with favorable effects on the outcomes. This article is a review of published literature on the current diagnostic and therapeutic modalities for LS, focusing on the pivotal role of echocardiography as the key diagnostic tool. Clinical suspicion of LS should prompt extensive investigation with non-invasive and where possible, invasive technics. Multicenter registers have a potential to assist the evaluation of long term outcomes of percutaneous trans-catheter therapies in patients with LS.

Impact of net atrioventricular compliance on clinical outcome in mitral stenosis

BACKGROUND

Net atrioventricular compliance (Cn) has been reported to be an important determinant of pulmonary hypertension in mitral stenosis (MS). We hypothesized that it may be useful in assessing prognosis because Cn reflects hemodynamic consequences of MS. To date, limited data with an assumed Cn cutoff have indicated the need for larger prospective studies. This prospective study was designed to determine the impact of Cn on clinical outcome and its contribution to pulmonary pressure in MS. In addition, we aimed to identify a cutoff value of Cn for outcome prediction in this setting.

METHODS AND RESULTS

A total of 128 patients with rheumatic MS without other significant valve disease were prospectively enrolled. Comprehensive echocardiography was performed and Doppler-derived Cn estimated using a previously validated equation. The end point was either mitral valve intervention or death. Cn was an important predictor of pulmonary pressure, regardless of classic measures of MS severity. During a median follow-up of 22 months, the end point was reached in 45 patients (35%). Baseline Cn predicted outcome, adding prognostic information beyond that provided by mitral valve area and functional status. Cn ≤4 mL/mm Hg best predicted unfavorable outcome in derivation and validation sets. A subgroup analysis including only initially asymptomatic patients with moderate to severe MS without initial indication for intervention (40.6% of total) demonstrated that baseline Cn predicted subsequent adverse outcome even after adjustment for classic measures of hemodynamic MS severity (hazard ratio, 0.33; 95% confidence interval, 0.14-0.79; P=0.013).

CONCLUSIONS

Cn contributes to pulmonary hypertension beyond stenosis severity itself. In a wide spectrum of MS severity, Cn is a powerful predictor of adverse outcome, adding prognostic value to clinical data and mitral valve area. Importantly, baseline Cn predicts a progressive course with subsequent need for intervention in initially asymptomatic patients. Cn assessment therefore has potential value for clinical risk stratification and monitoring in MS patients.

Intraoperative evaluation of transmitral pressure gradients after edge-to-edge mitral valve repair

Objective

Edge-to-edge repair of the mitral valve (MV) has been described as a viable option used for the surgical management of mitral regurgitation (MR). Based on the significant changes in MV geometry associated with this technique, we hypothesized that edge-to-edge MV repairs are associated with higher intraoperative transmitral pressure gradients (TMPG) compared to conventional methods.

Methods

Patient records and intraoperative transesophageal echocardiography (TEE) examinations of 552 consecutive patients undergoing MV repair at a single institution over a three year period were assessed. After separation from cardiopulmonary bypass (CPB), peak and mean TMPG were recorded for each patient and subsequently analyzed.

Results

84 patients (15%) underwent edge-to-edge MV repair. Peak and mean TMPG were significantly higher compared to gradients in patients undergoing conventional repairs: 10.7±0.5 mmHg vs 7.1±0.2 mmHg; P<0.0001 and 4.3±0.2 mmHg vs 2.8±0.1 mmHg; P<0.0001. Only patients with mean TMPG ≥7 mmHg (n = 9) required prompt reoperation for iatrogenic mitral stenosis (MS). No differences in peak and mean TMPG were observed among edge-to-edge repairs performed in isolation, compared to those performed in combination with annuloplasty: 11.0±0.7 mmHg vs 10.3±0.6 mmHg and 4.4±0.3 mmHg vs 4.3±0.3 mmHg. There were no differences in TMPG between various types of annuloplasty techniques used in combination with the edge-to-edge repairs.

Conclusions

Edge-to-edge MV repairs are associated with higher intraoperative peak and mean TMPG after separation from CPB compared to conventional repair techniques. Unless gradients are severely elevated, these findings are not necessarily suggestive of iatrogenic MS. Thus, in the immediate postoperative period mildly elevated TMPG can be expected and tolerated after edge-to-edge mitral repairs.

Determination of mitral valve area with echocardiography, using intra-operative 3-dimensional versus intra- & post-operative pressure half-time technique in mitral valve repair surgery

Background

We hypothesized that mitral valve areas (MVAs) with echocardiography, using 3D planimetry technique (measured at one point at maximal opening of mitral valve) versus pressure half-time technique (PHT, measured during entire diastolic phase) in mitral valve repair surgery (MVR) would be different.

Methods

Patients who had undergone MVR were retrospectively reviewed, and two different observers measured the MVAs using PHT and 3D planimetry technique. The MVAs derived from recorded medical data, using PHT and 3D planimetry technique were abbreviated to MVA-PHT1 and MVA-3D1, and data from the PHT and 3D planimetry techniques by observer A and observer B were determined as MVA-PHT2 and MVA-3D2, and MVA-PHT3 and MVA-3D3, respectively. The MVA derived by post-operative transthoracic echocardiography using the PHT technique was determined as MVA-TTE.

Results

Intraclass correlation coefficients were 0.90 for the intra-operative PHT technique and 0.78 for the intra-operative 3D planimetry technique. MVA-3D1 (2.91 ± 0.65 cm²), MVA-3D2 (3.00 ± 0.63 cm2) and MVA-3D3 (2.97 ± 0.88 cm²) were significantly larger than MVA-TTE (2.40 ± 0.59 cm²), but intra-operative MVAs-PHT were not. The biases and precisions were larger, and the correlation coefficients were lower in 3D planimetry technique compared with PHT technique.

Conclusions

MVA measured by 3D planimetry technique with TEE at the intra-operative post-MVR period was seemed to be larger than that measured by the PHT technique with TTE at the post-operative period. However, it did not mean that the 3D planimetry technique was inaccurate but needs cautions at determination of MVA using different techniques.

The role of echocardiography during mitral valve percutaneous interventions

Transesophageal echocardiography is routinely used to guide percutaneous interventions involving the mitral valve. Mitral balloon valvuloplasty for rheumatic mitral valve stenosis (MS) was the first percutaneous intervention to gain wide acceptance. New techniques have been developed to treat degenerative and functional mitral regurgitation (MR) as well as paravalvular mitral leak (PVML). This review describes the use of echocardiography for transcatheter treatment of MS, MR, and PVML.

Evaluation of transmitral pressure gradients in the intraoperative echocardiographic diagnosis of mitral stenosis after mitral valve repair

Objective

Acute mitral stenosis (MS) following mitral valve (MV) repair is a rare but severe complication. We hypothesize that intraoperative echocardiography can be utilized to diagnose iatrogenic MS immediately after MV repair.

Methods

The medical records of 552 consecutive patients undergoing MV repair at a single institution were reviewed. Post-cardiopulmonary bypass peak and mean transmitral pressure gradients (TMPG), and pressure half time (PHT) were obtained from intraoperative transesophageal echocardiographic (TEE) examinations in each patient.

Results

Nine patients (9/552 = 1.6%) received a reoperation for primary MS, prior to hospital discharge. Interestingly, all of these patients already showed intraoperative post-CPB mean and peak TMPGs that were significantly higher compared to values for those who did not: 10.7±4.8 mmHg vs 2.9±1.6 mmHg; p<0.0001 and 22.9±7.9 mmHg vs 7.6±3.7 mmHg; p<0.0001, respectively. However, PHT varied considerably (87±37 ms; range: 20–439 ms) within the entire population, and only weakly predicted the requirement for reoperation (113±56 vs. 87±37 ms, p = 0.034). Receiver operating characteristic curves showed strong discriminating ability for mean gradients (AUC = 0.993) and peak gradients (area under the curve, AUC = 0.996), but poor performance for PHT (AUC = 0.640). A value of ≥7 mmHg for mean, and ≥17 mmHg for peak TMPG, best separated patients who required reoperation for MS from those who did not.

Conclusions

Intraoperative TEE diagnosis of a peak TMPG ≥17 mmHg or mean TMPG ≥7 mmHg immediately following CPB are suggestive of clinically relevant MS after MV repair.

Can a novel echocardiographic score better predict outcome after percutaneous balloon mitral valvuloplasty?

OBJECTIVE

The assessment of patients with mitral stenosis before percutaneous balloon mitral valvuloplasty (PBMV) is crucial to predict outcome after the procedure. We tried to explore the prognostic power of a novel echocardiographic score to predict immediate postprocedural outcome in comparison to the standard score.

METHODS

We enrolled 50 consecutive patients with moderate to severe mitral stenosis admitted to undergo PBMV. For all patients, we assessed both the standard Massachusetts General Hospital (MGH) score and a novel score based on calcification (especially commissural) and subvalvular involvement. Patients underwent PBMV with the double balloon technique. Thereafter, patients were classified into two groups: group 1 (poor outcome) defined as no procedural success and/or increase of MR by more than 1 grade and group 2 (optimal outcome) defined as procedural success with increase of MR by 1 grade or less.

RESULTS

The total MGH score did not differ significantly between the two groups. However, among the individual parameters of the score, both calcification and subvalvular affection were significantly higher in group 1 versus group 2 (2.8 +/- 0.4 versus 1.7 +/- 0.8, and 2.4 +/- 0.5 versus 1.6 +/- 0.4, respectively, P < 0.01 for both). The total novel score and its two individual parameters (calcification and subvalvular involvement) were all significantly higher in group 1 versus group 2 (6 +/- 1.5 versus 2.9 +/- 1.9, 4.9 +/- 1.2 versus 2.4 +/- 1.5, 1.5 +/- 1.6 versus 0.5 +/- 0.9, respectively, P < 0.01 for all). Multivariate analysis demonstrated the novel score to be the only independent predictor of poor outcome.

CONCLUSION

The novel score is more reliable and correlates with outcome better than the standard score.