Mean Transmitral Pressure Gradient Research Articles

Echocardiographic Profiling Predicts Clinical Outcomes After Mitral Transcatheter Edge-to-Edge Repair.

Prior studies investigating the impact of residual mitral regurgitation (MR), tricuspid regurgitation (TR), and elevated predischarge transmitral mean pressure gradient (TMPG) on outcomes after mitral transcatheter edge-to-edge repair (TEER) have assessed each parameter in isolation. We sought to examine the prognostic value of combining predischarge MR, TR, and TMPG to study long-term outcomes after TEER. We reviewed the records of 291 patients who underwent successful mitral TEER at our institution between March 2014 and June 2022. Using well-established outcomes-related cutoffs for predischarge MR (≥moderate), TR (≥moderate), and TMPG (≥5 mm Hg), 3 echo profiles were developed based on the number of risk factors present (optimal: 0 risk factors, mixed: 1 risk factor, poor: ≥2 risk factors). Discrimination of the profiles for predicting the primary composite end point of all-cause mortality and heart failure hospitalization at 2 years was examined using Cox regression. Overall, mean age was 76.7±10.6 years, 43.3% were women, and 53% had primary MR. Two-year event-free survival was 61%. Predischarge TR≥moderate, MR≥moderate, and TMPG≥5 mm Hg were risk factors associated with the primary end point. Compared with the optimal profile, there was an incremental risk in 2-year event-rate with each worsening profile (optimal as reference; mixed profile: hazard ratio (HR), 2.87 [95% CI, 1.71-5.17], P<0.001; poor profile: HR, 3.76 [95% CI, 1.84-6.53], P<0.001). Echocardiographic profile was statistically associated with the 2-year mortality end point (optimal as reference; mixed profile: HR, 3.55 [95% CI, 1.81-5.96], P<0.001; poor profile: HR, 3.39 [95% CI, 2.56-7.33], P=0.02). The echocardiographic profile integrating predischarge TR, MR, and TMPG presents a novel prognostic stratification tool for patients undergoing mitral TEER.

Early Feasibility Study of a Hybrid Tissue-Engineered Mitral Valve in an Ovine Model.

Tissue engineering aims to overcome the current limitations of heart valves by providing a viable alternative using living tissue. Nevertheless, the valves constructed from either decellularized xenogeneic or purely biologic scaffolds are unable to withstand the hemodynamic loads, particularly in the left ventricle. To address this, we have been developing a hybrid tissue-engineered heart valve (H-TEHV) concept consisting of a nondegradable elastomeric scaffold enclosed in a valve-like living tissue constructed from autologous cells. We developed a 21 mm mitral valve scaffold for implantation in an ovine model. Smooth muscle cells/fibroblasts and endothelial cells were extracted, isolated, and expanded from the animal's jugular vein. Next, the scaffold underwent a sequential coating with the sorted cells mixed with collagen type I. The resulting H-TEHV was then implanted into the mitral position of the same sheep through open-heart surgery. Echocardiography scans following the procedure revealed an acceptable valve performance, with no signs of regurgitation. The valve orifice area, measured by planimetry, was 2.9 cm2, the ejection fraction reached 67%, and the mean transmitral pressure gradient was measured at 8.39 mmHg. The animal successfully recovered from anesthesia and was transferred to the vivarium. Upon autopsy, the examination confirmed the integrity of the H-TEHV, with no evidence of tissue dehiscence. The preliminary results from the animal implantation suggest the feasibility of the H-TEHV.

The Predictors and Outcomes of Functional Mitral Stenosis following Surgical Mitral Valve Repair: A Retrospective Analysis.

To optimize mitral valve repair outcomes, it is crucial to comprehend the predictors of functional mitral valve stenosis (FMS), to enhance preoperative assessments, and to adapt intraoperative treatment strategies. This study aimed to identify FMS risk factors, contributing valuable insights for refining surgical techniques. Among 228 selected patients, 215 underwent postoperative echocardiography follow-ups, and 36 met the FMS criteria based on a mean trans-mitral pressure gradient of >5 mmHg. Patients with FMS exhibited higher pulmonary systolic arterial pressure and increased late mortality during the follow-up. Univariable logistic regression analysis identified several risk factors for FMS, including end-stage renal disease, anterior leaflet lesion, concomitant aortic valve replacement, smaller ring size, ring type, and neochordae implantation. Conversely, resection alone and resection combined with neochordae implantation had protective effects against FMS. Multivariable logistic regression analysis revealed that smaller ring sizes and patch repair independently predicted FMS. When focusing on degenerative mitral regurgitation, the neochordae implantation without resection in leaflet repair, emerged as an independent predictor of FMS. Surgeons should weigh the substantial impact of surgical procedures on postoperative trans-mitral pressure gradients, emphasizing preoperative evaluation and techniques such as precise ring size assessment and effective leaflet management.

Long-Term Impact of Small Mitral Valve Orifice Area after Transcatheter Edge-to-Edge Mitral Valve Repair on Clinical Outcome: A Three-Dimensional Echocardiography Study

Iatrogenic mitral stenosis is a complication associated with transcatheter edge-to-edge mitral valve repair. Some reports revealed the impact of mean transmitral pressure gradient after procedure on long-term clinical outcomes. However, the association between prognosis and mitral valve orifice area (MVA) after the procedure has been poorly studied. This study aimed to investigate the association between postprocedural small MVA, derived from three-dimensional (3D) transesophageal echocardiography (TEE), and long-term clinical outcomes in 2 cohorts: the degenerative mitral regurgitation (MR) cohort and the functional MR cohort. This retrospective study assessed 279 consecutive patients with 3D TEE data during transcatheter edge-to-edge mitral valve repair between January 2010 and December 2016. Mitral valve orifice area after device implantation was measured by 3D planimetry. The patients with degenerative and functional MR were stratified separately into 2 groups according to postprocedural MVA: normal MVA (MVA > 1.5cm2) group and small MVA (MVA ≤ 1.5cm2) group. Of the 279 patients, 142 (51%) had degenerative MR and 137 (49%) had functional MR. The number of degenerative MR patients with small MVA was 38, whereas 42 patients were in the functional MR cohort. Patients with small MVA had higher rate of all-cause mortality in the degenerative MR group (log-rank test: P=.01) but not in the functional MR group (log-rank test: P=.52). In multivariate analysis small MVA was independently associated with all-cause mortality but not postprocedural transmitral pressure gradient. Neither small MVA nor transmitral pressure gradient was associated with all-cause mortality in patients with functional MR. Small MVA measured by 3D TEE after transcatheter mitral edge-to-edge repair was associated with poor prognosis in patients with degenerative MR.

Abstract 16946: The Optimal Surgical Procedure of Mitral Valve Repair According to Risk Analysis of Postoperative Functional Mitral Stenosis

Background: Functional mitral stenosis (FMS) after mitral valve repair (MVr) is associated with pulmonary hypertension in the late period, increasing the risk of re-operation and deterioration of long-term outcomes. However, the risk factors for FMS after MVr, especially the impact of surgical procedures, have not been thoroughly investigated. Hypothesis: We hypothesize that procedures of valve repair, including prosthetic ring orifice area (ROA), may be associated with FMS in the late period. Methods: We retrospectively evaluated 205 patients who underwent MVr using full annuloplasty rings between 2011 and 2021 at our institution. FMS was defined as mean trans-mitral pressure gradient (TMPG) ≥8 mmHg measured by annual echocardiography. ROA was determined by calculating the internal area of each valve type and size. Perioperative factors such as repair techniques, ROA, and ROA divided by BSA (ROAi) were used to analyze risk factors for FMS. The mean follow-up period was 4.8±0.4 years. Results: MVr was performed using artificial chordae in 110 cases and intervention in valve leaflet in 83 cases (resection suture: 43, cleft closure: 26, plication: 12, and edge-to-edge repair: 8). We also utilized semi-rigid full ring in all cases (26 or less: 15, 28: 53, 30: 73, 32: 49, 34 or more: 15). We identified postoperative FMS in 23 cases (11.2%, 2.5±0.9 years after MVr) with TMPG of 9.0 ± 0.7 mmHg. In the FMS group, decreasing TR-PG in the late period was not achieved after MVr. TR-PG in the late period was also significantly higher in the FMS group (28.3 ± 5.8 vs. 20.3 ± 2.1 mmHg, p=0.01). The freedom from re-operation for MV and re-hospitalization for heart failure rate was not significantly different in the two groups (93.6% vs. 95.5%, p=0.32, 87.7% vs. 90.6%, p=0.36, respectively). However, the freedom from MACE rate was lower in the FMS group (81.4% vs. 86.3%, p=0.11). Univariate analysis demonstrated that intervention in valve leaflet (OR 2.53, p=0.04) and ROAi (OR 0.98, p=0.005) were significant risk factors for FMS. Conclusion: Although further follow-up is mandatory, these results suggested that the use of sufficiently large prosthetic ring and avoidance of intervention in valve leaflet are efficient for preventing FMS and improving clinical outcomes after MVr.

Multidetector Computed Tomography in Patients Who Underwent Transcatheter Mitral Edge-to-Edge Repair

Multidetector computed tomography (MDCT) can provide valuable information for mitral assessment, but its role in transcatheter mitral edge-to-edge repair (TEER) planning has been poorly elucidated. We aimed to compare MDCT with 3-dimensional transesophageal echocardiography (3D-TEE) for TEER preprocedural evaluation. We analyzed the preprocedural MDCT and 3D-TEE of 108 consecutive patients with mitral regurgitation (MR) who underwent MitraClip implantation. The levels of agreement for the etiology and mechanism of MR, mitral calcification, mitral annulus, and mitral valve orifice area (MVOA) measurements were compared between MDCT and 3D-TEE data. Receiver-operating-characteristic curves were generated for mitral annulus area and MVOA using a low mean transmitral pressure gradient at discharge (<5mm Hg) as the state variable, and the primary outcome of all-cause mortality or rehospitalization for heart failure at 1 year was compared between MDCT's and 3D-TEE's MVOA <4-cm2 cutoff. Good levels of agreement between MDCT and 3D-TEE were observed for determining the etiology (κ=0.81) and mechanism (κ=0.62) of MR but not for grading mitral calcification (κ=0.31 to 0.35). The correlations between MDCT and 3D-TEE measurements were strong for mitral annulus area (r=0.90) and good for MVOA (r=0.73). Furthermore, no significant differences in the area under the receiver-operating-characteristic curve to predict low transmitral pressure gradient at discharge or the primary outcome at 1 year were detected between MDCT- and 3D-TEE-derived parameters (all p >0.05). In conclusion, in patients who underwent TEER with MitraClip, a high degree of agreement for comprehensive evaluation of MR and prediction of clinical outcomes between MDCT and 3D-TEE was observed.

Correlates and prognostic implications of LVEF reduction after transcatheter edge-to-edge repair for primary mitral regurgitation.

To explore the characteristics and outcomes of patients undergoing transcatheter edge-to-edge repair (TEER) for primary mitral regurgitation (MR) according to the presence of left ventricular ejection fraction (LVEF) reduction post-procedure. We retrospectively analysed 317 individuals [median age 83 (interquartile range, 75-88) years, 197 (62.1%) males] treated with an isolated, first-time TEER that was concluded by a successful clip deployment. Stratified by LVEF change at 1-month compared with baseline, the cohort was evaluated for residual MR and heart failure (HF) indices up to 1-year, as well as all-cause mortality and HF hospitalizations at 2-years. Overall, 212 (66.9%) patients displayed LVEF reduction, which was mainly driven by lowered total stroke volume and diffuse hypocontractility. While post-procedural MR, transmitral mean pressure gradient, and functional status were comparable in the two study groups, patients with LVEF reduction exhibited a greater decline in filling pressures intra-procedurally; left ventricular mass index, pulmonary arterial systolic pressure, and serum natriuretic peptide level at 1-month; and walking limitation at 1-year. Also, by 2 years, they were less likely to die (13.3% vs. 5.7%, P = 0.019), be readmitted for HF (17.1% vs. 9.0%, P = 0.033), and experience either of the two (23.8% vs. 12.7%, P = 0.012). Lastly, LVEF reduction was the only 1-month echocardiographic parameter to independently confer an attenuated risk for the composite of deaths or HF hospitalizations (HR 0.28, 95% CI 0.10-0.78, P = 0.016). LVEF reduction at 1-month post-TEER for primary MR is associated with better clinical outcomes, possibly reflecting a more pronounced unloading effect of the procedure.

What Is the Optimal Mitral Valve Repair for Isolated Posterior Leaflet Prolapse to Achieve Long-Term Durability?

Background This study assessed risk factors for mitral regurgitation (MR) recurrence or functional mitral stenosis during long-term follow-up in patients undergoing mitral valve repair for isolated posterior mitral leaflet prolapse. Methods and Results We assessed a consecutive series of 511 patients who underwent primary mitral valve repair for isolated posterior leaflet prolapse between 2001 and 2021. Annuloplasty using a partial band was selected in 86.3%. The leaflet resection technique was used in 83.0%, whereas the chordal replacement without resection was used in 14.5%. Risk factors were analyzed for MR recurrence ≥grade 2 or functional mitral stenosis with mean transmitral pressure gradient ≥5 mm Hg using a multivariable Fine-Gray regression model. The 1-, 5-, and 10-year cumulative incidence of MR ≥grade 2 was 7.8%, 22.7%, and 30.1%, respectively, whereas that of mean transmitral pressure gradient ≥5 mm Hg was 8.1%, 20.6%, and 29.3%, respectively. Risk factors for MR ≥grade 2 included chordal replacement without resection (hazard ratio [HR], 2.50, P<0.001) and larger prosthesis size (HR, 1.13, P=0.023), whereas factors for functional mitral stenosis were use of a full ring (partial band versus full ring, HR, 0.53, P=0.013), smaller prosthesis size (HR, 0.74, P<0.001), and larger body surface area (HR, 3.03, P=0.045). Both MR ≥grade 2 and mean transmitral pressure gradient ≥5 mm Hg at 1 year post surgery were significantly associated with the long-term incidence of reoperation. Conclusions Leaflet resection with a large partial band may be an optimal strategy for isolated posterior mitral valve prolapse.

Prognostic value of mitral valve haemodynamic parameters obtained by intraprocedural echocardiography in transcatheter edge-to-edge repair.

To assess whether intraprocedural transesophageal echocardiographic (TEE)-derived haemodynamic parameters predict outcomes in patients undergoing transcatheter edge-to-edge repair (TEER) for mitral regurgitation (MR). This is a single-centre, retrospective analysis encompassing 458 (IQR, 104-1035) days of follow-up after 926 consecutive patients [481 (52%) with functional MR] referred to an isolated mitral TEER between 2013 and 2020. Cases without actual clip deployment, or in whom prior mitral procedures had taken place, were excluded. The primary outcome was the combined rate of all-cause mortality or heart failure (HF) hospitalizations. Secondary endpoints included single components of the primary outcome, as well as MR severity at one month and one year following the procedure. A multivariable analysis identified two intraprocedural echocardiographic observations made after clip deployment as independent predictors of the primary outcome: an above mild MR (HR for whole study period 1.49, 95% CI 1.05-2.13, P = 0.026) and a 100% or more increase from baseline in the transmitral mean pressure gradient (TMPG) (HR for whole study period 1.32, 95% CI 1.01-1.72, P = 0.039). Also, MR grade of above mild and the absence of a normal pulmonary venous flow pattern (PVFP) bilaterally were associated with an increased risk for HF hospitalizations and greater-than-mild 1-month MR. No prognostic role was demonstrated for the change in MR severity, the absolute TMPG, or the mere improvement in PVFP. Immediate post-TEER MR severity and the relative change in TMPG are predictive of clinical and echocardiographic outcomes following the procedure.

Abstract 12459: Hemodynamic Progression of Mitral Annular Calcification: Prevalence, Characteristics, and Clinical Implications

Background: A recent study demonstrated that transmitral mean diastolic pressure gradient (MDPG) in patients with mitral annular calcification (MAC) is associated with increased mortality, however, the longitudinal hemodynamic progression over time in patients with MAC and its characteristics are unclear. In this study, the clinical and echocardiographic characteristics of MAC correlated with hemodynamic progression and its clinical implications were investigated. Methods: In total, 161 patients (mean age 74.7±10.5 yeas, 63 men) with MAC were identified by index transthoracic echocardiography (TTE) between January 2012 and June 2016 and performed follow-up TTE after 3 years. Stable MAC (n=146, 90.7%) was defined as a difference of transmitral mean pressure gradient (MDPG) less than 2 mmHg between initial and follow-up TTE, and progressive MAC (n=15. 9.5%) was defined as MDPG increased above 2mmHg. Results: There was no significant difference of baseline characteristics between the group with stable MAC and progressive MAC. In the group of progressive MAC compared to that of stable MAC, a proportion of moderate-to-severe MAC (66.7 vs. 28.1%, p =0.002), significant MS (26.7 vs. 8.2%, p =0.046), maximal thickness of MAC (0.7±0.5 vs. 0.5±0.3, p =0.023), and MDPG (2.8±1.7 vs. 2.2±1.5, p =0.048) were significantly higher at the index TTE ( Figure ). In the group with progressive MAC, increase in left atrial (LA) volume index and pulmonary artery systolic pressure were significant. In-5-year mortality and newly developed atrial fibrillation tended to be more common in progressive MAC group, but there was no statistical significance. Conclusions: Hemodynamic progression occurs in about 10% of patients over 3 years. Patients with progressive MAC have larger baseline MAC thickness and calcification extent, even if MDPG is less than 3 mmHg. Patients with progressive MAC are more likely to develop LA enlargement and pulmonary hypertension, which are prone to poor outcome.

Midterm Outcomes After Surgical Management for Mitral Valve Regurgitation in Infancy.

Mitral valve repair is preferred for pediatric mitral valve disease. However, it is technically difficult because of complex lesions, poor surgical exposure, and tissue fragility, especially in infants. We investigated the midterm outcomes of mitral valve surgery for mitral regurgitation in infancy. We retrospectively reviewed 18 patients (aged <12 months old) undergoing mitral valve surgery for mitral regurgitation at our institution between October 2005 and March 2019. The patients had 10 acquired and 8 congenital valve lesions as follows: torn chordae (n = 6), leaflet prolapse (n = 4), posterior leaflet hypoplasia (n = 3), anterior leaflet cleft (n = 2), infective endocarditis (n = 1), papillary muscle rupture (n = 1), and hammock valve (n = 1). All patients initially underwent mitral valve repair. There was no operative mortality, and 1 case of late death. The median follow-up period was 7 years and 9 months. Reoperation was performed in 3 patients, re-repair (twice) in 1 patient with a hammock valve, and mitral valve replacement in 2 patients. Fifteen patients had at most mild mitral regurgitation at the last follow-up. A transmitral mean pressure gradient of over 5 mm Hg was observed in 3 cases, including the patient with a hammock valve. Postoperative mitral annular diameter increased within the normal range in all patients. Survival and reoperation-free rates at 5 and 10 years were 94.4% and 83.0%, respectively. Mitral valve repair for mitral regurgitation in infancy is safe and feasible with satisfactory midterm outcomes, even under serious preoperative conditions.

Prognostic significance of mean transmitral pressure gradient in degenerative non-rheumatic mitral valve: insights from a vast echocardiographic database

Abstract Background The incidence and prevalence of senile, non-rheumatic mitral valve disease are increasing and there is a renewed interest in new transcatheter structural cardiac interventions intended to treat that valvular disorder. While the severity of rheumatic mitral valve disease can be accurately assessed by echocardiography using various parameters, including mean transmitral pressure gradient, these methods have been questioned for quantifying senile mitral valve disorder and their prognostic significance is still unknown. Aims The current study aims to document the natural history of patients with elevated senile mean transmitral pressure gradient (MG) and assess its prognostic significance. Methods A vast institutional echocardiography database was retrospectively analyzed from 2009 to 2020 for all patients aged over 60 years with a detailed echocardiography report with valid measurement of transmitral gradients. Patients with rheumatic valvular disease or who underwent surgical or transcatheter valvular replacement/repair were excluded. All-cause mortality was set to be the primary outcome, and survival models utilizing univariable and adjusted multivariable analysis for various clinical and echocardiographic variables were applied. Results A total of 5524 patients consisted of the final cohort. They were stratified by the MG into three groups: MG &amp;lt;3 (2914 patients, 53%), 3≤MG&amp;lt;6 (2079 patients, 37.6%) and MG ≥6 mmHg (531 patients,9.6%). The mean age of the total cohort was 77.2±7.9 years; 60.5% were female, 33.3% with diabetes mellitus, 15.1% with chronic kidney disease, and 14.1% with ischemic heart disease. An Adjusted Cox proportional hazard regression model demonstrated that MG is independently associated with all-cause mortality (adjusted HR 1.04 per 1 mmHg increase, 95% CI 1.02–1.05, p&amp;lt;0.001). Moreover, an elevated MG was associated with a rise in all-cause mortality (HR of 1.15 and 1.4 for patients with 3≤MG&amp;lt;6 and MG ≥6 mmHg, respectively (Fig. 1). Conclusion The elevated mean transmitral gradient in senile non-rheumatic valves is an independent predictor for all-cause mortality. Interventions and prospective trials intended to mitigate that risk should be needed. Funding Acknowledgement Type of funding sources: None.

Determinants of exercise-induced pulmonary hypertension in rheumatic mitral stenosis: a study with exercise stress and speckle tracking echocardiography

Abstract Backgrounds Exercise stress echocardiography is helpful in assessing hemodynamic consequence of mitral stenosis (MS) and in guiding treatment. Exercised-induced pulmonary hypertension (PH) is result of severity of MS, but myocardial function of left ventricle and clinical factors can also have effect. Purpose We aimed to evaluate the associated factors with the pulmonary artery systolic pressure (PASP) in exercise stress echocardiography through 2D, Doppler, and speckle tracking imaging in patients with rheumatic MS. Methods A total of 164 patients with rheumatic MS underwent a graded, symptom-limited, supine bicycle exercise with echocardiography. After exclusion of patients who had very severe MS (valve area &amp;lt;1.0 cm2), a history of surgery or recent percutaneous mitral valvotomy, combined significant aortic valve dysfunction, left ventricular (LV) ejection fraction &amp;lt;50%, we analyzed 113 patients (77.6% female; mean age, 56±9 years). Echocardiographic parameters at rest, each stage (25 watt increment every 3 minutes), and peak exercise were obtained. Exercised induced PH was defined as present if PASP &amp;gt;60 mmHg at peak exercise. LV global longitudinal strain (LV-GLS) and left atrial (LA) strain were analyzed by software. The subjects were divided into 4 groups according to mean transmitral pressure gradient (MG) (15 mmHg) and PASP (60 mmHg) at peak exercise (Group 1, MG &amp;lt;15 mmHg and PASP &amp;lt;60 mmHg, n=29; Group 2, MG &amp;lt;15 mmHg and PASP ≥60 mmHg, n=9; Group 3, MG ≥15 mmHg and PASP &amp;lt;60 mmHg, n=23; Group 4, MG ≥15 mmHg and PASP ≥6 0mmHg, n=52). Results The mean mitral valve area was 1.30±0.23 cm2. PASP increased from 30.0±8.0 mmHg at rest to 61.0±14.8 mmHg at peak exercise, along with increase MG. 61 (53.9%) subjects had PASP&amp;gt;60 mmHg at peak exercise. Compared to group 1, group 2 had higher incidence of diabetes mellitus (DM) and significantly elevated PASP at baseline and impaired LV-GLS. However, there was no statical difference in LA strain between the two groups. In subjects with MG above 15 mmHg (Group 3 and 4), a similar trend was observed in occurrence of exercise-induced PH. On logistic multivariate regression, exercised induced PH was independently associated with female (HR: 5.35, 95% CI: 1.51–24.95; p=0.032), DM (HR: 10.05, 95% CI, 1.35–74.45; p=0.024), MG at peak exercise (HR: 1.17, 95% CI, 1.02–1.34; p=0.002), PASP at rest (HR: 1.17, 95% CI, 1.05–1.30; p=0.002), and LV-GLS (HR: 1.45, 95% CI, 1.09–1.91; p=0.009), but not with LA strain. The predictive value for exercised induced PH was highest when adding LV-GLS to the clinical factor (age, sex, DM) and echocardiographic parameters (Figure 1). Conclusions Exercised induced PH is affected by not only hemodynamic consequence of MS, but also myocardial function of left ventricle and clinical factors. Therefore, when determining the optimal timing of intervention based on exercise-induced PH in rheumatic MS patients, LV-GLS should be evaluated comprehensively along with MS characteristics. Funding Acknowledgement Type of funding sources: Private hospital(s). Main funding source(s): Yonsei University College of Medicine

Patient–Prosthesis Mismatch Associated With Somatic Growth After Mechanical Mitral Valve Replacement in Small Children: Metrics for Reoperation and Outcomes

Reoperation after pediatric mitral valve replacement (MVR) is inevitable due to patient-prosthesis mismatch (PPM) associated with somatic growth. We analyzed potential metrics for PPM and outcomes of redo MVR for valve upsizing. Between 1999 and 2018, 15 children without obstructive left heart lesions other than mitral stenosis underwent initial MVR with a 16-mm ATS-Advanced Performance valve. We analyzed hemodynamic data from 28 postoperative catheterizations and concomitant echocardiograms. The median age and body weight at initial MVR were 4.9 months (25th, 75th percentile: 3.6, 6.6) and 5.9 kg (5.0, 7.3). Redo MVR was planned when patients had congestive heart failure and postcapillary pulmonary hypertension (PH) due to PPM: systolic pulmonary arterial pressure (SPAP) >35 mm Hg and pulmonary capillary wedge pressure (PCWP) >15 mm Hg on catheterization. Indexed effective orifice area (iEOA) and mean transmitral pressure gradient (TMPG) were strongly correlated with SPAP (r = -0.72, P < 0.001 and r = 0.75, P < 0.001) and PCWP (r = -082, P < 0.001 and r = 0.84, P < 0.001). Cut-off values for detecting postcapillary PH due to PPM were 1.0 cm2/m2 for iEOA and 18 mm Hg for mean TMPG. Nine patients underwent redo MVR for postcapillary PH due to PPM at a median postoperative interval of 10 years (9.2, 11.9). All the patients survived, and PH was improved one year after surgery. iEOA and mean TMPG can be metrics for PPM in children after MVR. Careful follow-up is required to confirm the improvement of preoperatively existing PH after redo MVR for valve upsizing.

Clinical and echocardiographic differences in three different etiologies of severe mitral stenosis.

In our institute, the causes of mitral stenosis (MS) are generally categorized into three main etiologies-rheumatic MS (RMS), degenerative MS with annular and leaflet calcification, and post-clip MS as a consequence of transcatheter mitral valve repair with clips for treating mitral regurgitation. However, clinical differences among the three etiologies are uncertain. We retrospectively assessed 293 consecutive patients (53 with RMS, 118 with degenerative MS, and 122 with post-clip MS) who had a three-dimensional (3D) transesophageal echocardiography (TEE) derived mitral valve orifice area (MVA) of ≤1.5cm2 , and a mean transmitral pressure gradient of ≥5 mmHg on transthoracic echocardiography. Although there was no difference in 3D-TEE-derived MVA among the three groups, patients with post-clip MS had a significantly lower mean transmitral pressure gradient compared to those with either of the other two types of MS (10.8 ([7.9-15.2] mmHg vs. 9.6 [7.3-12.5] mmHg vs. 6.9 [6.0-9.2] mmHg; p<.001). Patients with RMS had a higher prevalence of dyspnea. The independent determinants of dyspnea were pressure half time in RMS, 3D-TEE-derived MVA and estimated right atrial pressure in degenerative MS, and left ventricle ejection fraction in post-clip MS. Patients with post-clip MS had the lowest mean transmitral pressure gradient, and patients with RMS had the highest prevalence of dyspnea, despite having a similar 3D-TEE-derived MVA. The determinants of dyspnea were different among the three etiologies of MS.

Three-dimensional echocardiography for predicting mitral stenosis after MitraClip for functional mitral regurgitation.

Postprocedural mitral stenosis (MS), or increased transmitral mean pressure gradient (TMPG), is one of the limitations of transcatheter edge-to-edge mitral valve repair using MitraClip (Abbott Vascular Inc., Santa Clara, USA); however, the usefulness of three-dimensional transesophageal echocardiography (3D-TEE) for predicting postprocedural MS in functional mitral regurgitation (MR) has not been fully elucidated. Eighty-two consecutive functional MR patients who underwent transcatheter mitral valve repair using MitraClip were retrospectively studied. Postprocedural MS was defined as TMPG ≥ 5mmHg by echocardiography. Ten patients had postprocedural MS, and 3D-TEE showed that patients with postprocedural MS had smaller preprocedural mitral valve orifice area (MVOA), anteroposterior and mediolateral diameter, leaflet area, and annulus area. Receiver operating characteristic analysis showed that leaflet area (area under the curve (AUC) 0.829), annulus area (AUC 0.813), anteroposterior diameter (AUC 0.797) and mediolateral diameter (AUC 0.803) evaluated using 3D-TEE were predictors of postprocedural MS, and their predictive abilities were higher than those of preprocedural MVOA (AUC 0.756) and preprocedural TMPG (AUC 0.716). Adding leaflet area to TMPG and MVOA resulted in higher C-statistics for predicting postprocedural MS (from0.716to0.845 and from0.756to0.853, respectively). In functional MR patients treated with MitraClip, leaflet area and annulus area evaluated using 3D-TEE had high predictive values for postprocedural MS, and their predictive abilities were higher than those of preprocedural TMPG or MVOA.

Measurement of mitral valve area by direct three dimensional planimetry compared to multiplanar reconstruction in patients with rheumatic mitral stenosis.

Mitral valve area (MVA) measurement by three-dimensional transesophageal echocardiography (3D-TEE) has a crucial role in the evaluation of mitral stenosis (MS) severity. Three-dimensional direct (3D-direct) planimetry has been proposed as a new technique to measure mitral valve area. This study aimed to compare the 3D-direct mitral valve planimetry to conventional three-dimensional multiplanar reconstruction (3D-MPR) in severe MS using 3D-TEE. In this cross-sectional, prospective study; 149 patients with severe MS who were referred for transesophageal echocardiography in Shahid Madani Hospital (Tabriz Iran), just before percutaneous transmitral commissurotomy (PTMC), recruited consecutively. All patients underwent 2D transthoracic echocardiography (2D-TTE) and 3D-TEE in a single session before PTMC. During 2D-TTE planimetry, pressure half time (PHT), and proximal isovelocity surface area (PISA) were applied to measure the MVA. Transmitral mean pressure gradient (MPG) was measured. During 3D-TEE, MVA planimetry was carried out with both 3D-direct and 3D-MPR methods. 3D-direct was applied from both atrial and ventricular views. The consistency of MVA measurements with 3D-direct, 3D-MPR, and 2D-TTE methods was statistically investigated. Our sample consisted of 109 (73.2%) women and 40 (26.8%) men. The mean age was 51.75 ± 9.81years. The agreement between 3D-direct and 3D-MPR planimetry was significant and moderate (0.99 ± 0.29cm2 vs. 1.12 ± 0.26cm2, intraclass correlation = 0.716, p value = 0.001).The accuracy of the 3D-direct method reduced significantly compared to the MPR method at MVA > 1.5cm2. The maximum difference between two methods was observed in cases with MVAs larger than 1.5cm2. MVA measured with the 3D-MPR method was significantly correlated with a 2D-TTE method, with a moderate agreement (intraclass correlation = 0.644, p value = 0.001). Also, 2D-TTE and 3D-direct TEE techniques yielded significantly consistent measurements of the MVA (1.06 ± 0.026cm2 vs. 0.99 ± 0.29cm2, intraclass correlation = 0.787, p value = 0.001); however, with a slight overestimation of the MVA by the former with a net difference of 0.06 ± 0.013cm2. Mitral valve pressure gradient (MPG) had no significant correlation with planimetry results. A significant inverse correlation was seen between the MVA and pulmonary arterial systolic pressure. 3D-direct planimetry has an acceptable agreement with 3D-MPR planimetry at MVA less than 1.5cm2, but their correlation decreases significantly at MVA above 1.5cm2. 3D-direct planimetry underestimates MVA compared to 3D-MPR, especially at MVA above 1.5cm2. It seems that the saddle shape of mitral valve, interferes with 3D-direct measurement of commissures at moderate MS. The 2D-TTE planimetry has generally acceptable accuracy, but its correlation to the 3D-TEE methods is significantly reduced in cases with moderate to severe MS (i.e. MVA > 1.0cm2).

Abstract 11497: Echocardiographic Features of Severe Mitral Stenosis in Three Different Etiologies

Background: In our Heart Center, the cause of mitral stenosis (MS) is usually classified into 3 different categories/etiologies, namely, rheumatic disease, degenerative disease with annular or leaflet calcification, and MS as a consequence of a transcatheter mitral repair with clips for mitral regurgitation. However, differences in the morphology and echocardiographic evaluation among the three etiologies have not been fully elucidated. The aim of this study is therefore to investigate differences in echocardiographic features of these three etiologies of MS. Method: We retrospectively studied 157 patients who underwent three-dimensional transesophageal echocardiography (3D TEE) at Cedars-Sinai Medical Center between January 2012 and December 2020, and had severe mitral stenosis defined as 3D TEE derived mitral valve orifice area (MVA) of ≤ 1.0 cm 2 .These patients also had a mean transmitral pressure gradient of ≥ 5 mmHg on transthoracic echocardiography which was performed within 6 months before and after TEE. Other clinical and echocardiographic characteristics were obtained from medical records. Result: Of 157 patients, 37 patients had rheumatic MS, 60 patients had degenerative calcific MS and 60 patients had post-clip MS. There was no significant difference among the three groups in 3D TEE derived MVA (Table). Despite comparable 3D derived MVA, patients with post-clip MS had significantly lower mean transmitral pressure gradient than those with other 2 types of MS. Patients with rheumatic MS had larger indexed left atrial volume than patients with other 2 types of MS. Patients with degenerative calcific MS and those with post-clip MS had larger MVA both by pressure half time and by continuity equation than patients with rheumatic MS. Conclusion: There were distinct differences in echocardiographic features among the three MS etiologies. The optimal evaluation method and multi-parameter determined grading of MS severity may differ depending on the etiology.

Prevalence of mitral annular calcification and its association with mitral valvular disease.

Mitral annular calcification (MAC) is increasingly observed in elderly population. The purpose of this study was to investigate incidence of MAC and its association with mitral valvular disease (MVD). A total of 13,483 consecutive patients who underwent echocardiography were enrolled. MAC was defined as an echo-dense, shelf-like structure with an irregular, lumpy appearance involving the mitral valve annulus, with acoustic shadowing. Prevalence of MAC and its association with significant mitral stenosis (MS) or mitral regurgitation (MR) were studied. Significant (≥moderate) MS was defined as mean transmitral valvular pressure gradient>5mm Hg and significant MR was defined as ≥moderate MR based on quantitative or semi-quantitative Doppler methods. MAC was present in 1881 of 13,483 patients (14%). Patients with MAC (MAC group) was older and more female gender than those without MAC (non-MAC group). Significant MS was present in 2.2% of MAC and in .6% of the non-MAC group (p<0.0001). Significant MR was present in 11.9% of MAC and in 5.0% of the non-MAC group (p<0.0001). Co-existence of MAC and aortic valve replacement (AVR) was associated with increased prevalence of MVD (MS:11.4%, MR:17.2%, respectively). MAC was present in 14% of the patients and was associated with significant MVD. Co-existence of MAC and AVR may increase the risk of MVD.

Transcatheter mitral valve repair (TMVR) using MitraClip in patients younger than 65 years: a multicenter analysis of 2-years outcomes

Abstract Background TMVR using MitraClip became a well-established interventional therapy for severe MR. However, TMVR has been almost only applied to old aged patients rejected from surgical therapy. Objective To present 2-years outcomes of 36 patients younger than 65 years with no surgical options treated by TMVR. Methods A retrospective clinical and TEE study was conducted to evaluate 36 patients younger than 65 years treated by TMVR in 3 heart centers. Results Mean age of the 36 study patients was 56.3±6.6 years, male gender was 72.2%. High operative risk was estimated by STS score (mean = 8.73±2.97) and EuroSCORE (mean = 24.71±12.79). All patients were refused for surgery by heart team decision, therefore admitted to TMVR. Baseline severity of MR was assessed by 3D-TEE based biplane vena contracta width (mean = 8.35±1.87 mm). Baseline transmitral mean pressure gradient was 1.81±0.78 mmHg. 21 patients showed mitral annular dilatation as the main cause of MR, 8 patients had leaflet prolapse, 4 patients exhibited papillary muscle displacement leading to leaflet tethering and 3 patients showed mitral leaflet thickening and/or retraction due to fibrosis. Procedural success was achieved in all patients with 1/2/3 clips implanted in 52.8%/44.4%/2.8% of cases with a mean of 1.5 clip per case. Two grades or more reduction in severity of MR (MR grade ≤ II/IV) was accomplished in 88.9% of patients. Mean postprocedural MPG was 3.78±1.96 mmHg. Average follow-up (FU) period was 25,8 months and the median was 20 months (25th–75th percentile: 12–36 months). During 2-years FU, statistically significant difference (p value &amp;lt;0.002) was detected for NT-proBNP levels compared to baseline (mean = 9870±10819, median = 7748, 25th–75th percentile: 2702–14237 pg/ml) and at follow up visits (mean = 7645±11292, median = 3263, 25th-75th percentile: 883–8078 pg/ml). Furthermore, persistent symptomatic improvement during FU, defined as NYHA functional class improvement by 2 or more Grades, was achieved in 69% of patient in parallel with efficient reduction of MR in 34 patients so that a second intervention by reclipping was required in 2 patients to correct recurrent significant MR. Only two patients experienced procedure-related complications by large puncture site hematoma. No procedure-related mortality during the first 30 days was detected. However, mortality was recorded in 2 patients during the first month and was attributed to severe advanced heart failure in one case and septicemia after exclusion of infective endocarditis in another case. Over 2 years FU, other 5 patients passed away, 3 cases owing to advanced heart failure, one case due to multi-organ failure and one because of tumor disease. Conclusion TMVR in patients younger than 65 years refused from surgical repair provides satisfactory clinical and echocardiography outcomes at 2 years. Future studies should evaluate the outcomes of MitraClip in this population in a larger cohort. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Hassan M.H. Mohammed received a scholarship grant from the Egyptian ministry of higher education and Minia University, Egypt.