Transmitral Gradient Research Articles

Effects of boundary conditions on the transmitral pressure gradient for numerical simulation of flow in a left heart model

The transmitral pressure gradient is a crucial clinical indicator for diagnosing mitral regurgitation and stenosis. Numerical simulation of specific patients can obtain the complete pressure distribution in the left heart system, which is an important approach to evaluate cardiac function. However, the results are sensitive to the boundary conditions used in the numerical simulations. In the present work, we constructed a left heart model and assessed the effects of four typical boundary conditions on the transmitral pressure gradient, which is computed based on the Bernoulli equation and the line probe, respectively. The results show that the transmitral pressure gradient obtained by the line probe is sensitive to the boundary conditions. The sensitivity is closely related to the pressure in the atrium but has negligible effect on the pressure in the ventricle. This study sheds light on evaluating the pressure gradient of patient-specific treatments based on the numerical simulation of a left heart model.

Elevated Trans-mitral Pressure Gradient Predicts Surgery in Young People with Moderate-Severe Rheumatic Mitral Regurgitation.

Mitral regurgitation (MR) is the most common lesion in children with rheumatic heart disease (RHD). Progression of RHD results in the need for surgical intervention, the timing of which is dictated by left ventricular dilatation and the onset of heart failure symptoms. We sought to determine whether elevation in trans-mitral pressure gradient (TMPG) in those with moderate or severe rheumatic MR without significant mitral stenosis (MS) could predict the need for future surgical intervention. Echocardiographic studies were reviewed for 116 children and young people with moderate or severe rheumatic MR. Those with significant mitral stenosis or concurrent aortic valve disease were excluded. Trans-mitral pressure gradient was measured at baseline and details of mitral valve surgical intervention were retrieved from a registry database. Time to future surgery (up to six years) was compared between those with TMPG < 5mmHg and TMPG ≥ 5mmHg. Survival curves demonstrated an increased risk of surgery for those with TMPG ≥ 5mmHg with Cox proportional regression analysis providing a hazard ratio of 5.8. The proportion free from mitral valve surgery at one year for the TMPG < 5mmHg group was 0.94 (95% CI 0.86-0.97), compared to 0.62 (95% CI 0.42-0.77) in the ≥ 5mmHg group. Trans-mitral pressure gradient is a strong predictor of future mitral valve surgery in children and young people with significant rheumatic MR without MS. This non-invasive measure could be used to signal the need for more aggressive monitoring in order to optimize the timing of intervention.

Transmitral Pressure Gradients in Patients With Degenerative Mitral Regurgitation After Robotic Mitral Valve Repair With Leaflet Preservation Techniques.

The hemodynamic effects of mitral valve repair (MVr) with respect to transmitral pressure gradients (TMPGs) have not been described well in patients undergoing leaflet preservation techniques. In a population of patients undergoing robotic MVr with leaflet preservation, we investigate the expected change of the postrepair intraoperative TMPG in the postoperative follow-up period. We retrospectively studied 144 adult patients who underwent robotic MVr. Demographic, clinical, procedural, and echocardiographic data were collected and analyzed. We found a slight increase in the mean TMPG from the intraoperative postrepair to the immediate postoperative period (intraoperative 3.3 ± 1.4mmHg vs. first postoperative transthoracic echocardiography [TTE] follow-up 3.6 ± 1.9mmHg, p = 0.016) with a gradual decline in the long-term follow-up (mean TMPG at last follow-up TTE 2.4+2.1mmHg). When dichotomizing the patient population using a cutoff of 3mmHg for the intraoperative mean TMPG, patients with an intraoperative mean TMPG > 3mmHg had higher mean TMPG gradients at first TTE (4.5 ± 2.4 vs. 3.1 ± 1.3mmHg, p<0.001) as well as at last TTE (3.0± 2.2 vs. 2.1 ± 2.0mmHg, p = 0.01) when compared with patients with an intraoperative mean TMPG ≤ 3mmHg. There was no difference in clinical outcomes. Although the hemodynamic effect of MVr seems to be small, patients with an intraoperative TMPG > 3mmHg have a higher mean TMPG at follow-up. The hemodynamic effect does not seem to have an impact on clinical outcome.

Immediate and short-term outcomes of percutaneous balloon mitral commissurotomy for severe mitral stenosis at a Resource Limited Setting, Addis Ababa, Ethiopia

BackgroundRheumatic heart disease is a common cause of mitral stenosis (MS) in developing nations. Percutaneous mitral balloon commissurotomy (PMBC) is the treatment of choice for patients with MS with favorable anatomy. ObjectiveThis study aimed to assess immediate and short-term outcomes of percutaneous balloon mitral commissurotomy for symptomatic patients with rheumatic severe mitral stenosis. MethodsThe clinical records of patients who underwent Percutaneous Mitral Balloon Commissurotomy (PBMC) at Saint Paul Hospital Millennium Medical College, Cardiac Center were reviewed. A retrospective observational study was conducted from February 01, 2018, to August 30, 2021. All eligible patients who underwent Percutaneous Mitral Balloon Commissurotomy during the study period at the cardiac center were included in this study. Ninety-one patients were enrolled in the study after excluding repeat procedures, those with incomplete data, and lost medical records. Data were collected through chart reviews using a structured questionnaire by trained physicians, with daily supervision by the investigators. Data analysis was performed using SPSS version 25. Associations were checked using a paired t-test and Fisher's Exact Test, with statistical significance set at a p-value of <0.05. ResultPercutaneous mitral balloon commissurotomy was successful in 91.2 % of patients. Following the procedure, there was a significant increase in the mean mitral valve area from 0.799 cm2 to 1.674 cm2 and a reduction in the trans-mitral mean pressure gradient from 20 mmHg to 7.71 mmHg (P < 0.001). Atrial fibrillation and a high Wilkins score were identified as correlates of non-successful PMBC. A Wilkin's score of ≤8 and a post-procedure mitral valve area > 1.5 cm2 were associated with New York Heart Association functional class improvement three months after the procedure. ConclusionIn this study, percutaneous mitral balloon Commissurotomy (PMBC) demonstrated an excellent success rate. The majority of patients exhibited significant improvement in the New York Heart Association (NYHA) functional class.

Transcatheter aortic valve implantation for combined aortic and mitral stenoses: Insights from the OCEAN-TAVI Registry.

Mitral stenosis (MS) occasionally coexists with aortic stenosis (AS). Limited data are available regarding the functional class and clinical outcomes of patients who undergo transcatheter aortic valve implantation (TAVI) for combined AS and MS. This study compared the clinical outcomes in patients with and without MS who underwent TAVI for severe AS and assessed the impact of mitral annulus calcification (MAC) severity, transmitral gradient (TMG) and mitral valve area (MVA) on outcomes in patients with combined AS and MS. We investigated patients in the OCEAN-TAVI registry who underwent TAVI. MS was defined as an MVA≤1.5cm2 or TMG≥5mmHg. The composite of all-cause death and admission for heart failure was compared between patients with and without MS. The impact of MAC, TMG and MVA on outcomes was assessed in patients with combined AS and MS. We identified 106 patients with MS (MAC 84%; TMG 6.4±2.6mmHg; MVA 1.10±0.31cm2) and 6570 without MS as controls. The MS group was older (85±5 vs. 84±5years, P=0.033), more of women (85 vs. 67%, P<0.01), and had a higher risk of surgery (the Society of Thoracic Surgeons Mortality Score 8.7±5.1 vs. 7.6±5.9, P=0.047) than the controls. In the MS group, the New York Heart Association Functional Class was 3 or 4 in 56% of the patients at baseline and 6% at 1year after TAVI. Thirty-day mortality (2.8% vs. 1.3%, P=0.18) and early composite outcomes (17% vs. 15%, P=0.56) were comparable between patients with and without MS. During a median follow-up of 2.1years, the presence of MS was associated with a higher incidence of adverse events compared with controls (adjusted hazard ratio [HR] 1.84; 95% confidence interval [CI] 1.34-2.51, P<0.01), even on propensity score matched analysis (adjusted HR 1.91; 95% CI 1.14-3.22, P<0.01). Moderate or severe MAC contributed to increased risk of adverse events in patients with MS (adjusted HR 2.89; 95% CI 1.20-6.99, P=0.018), but TMG and MVA did not. In patients undergoing TAVI for severe AS, those with moderate or severe MS experienced worse outcomes after TAVI compared with those without MS. Patients with combined AS and MS sustained symptom improvement at 1-year post-TAVI. MAC severity was a useful predictor of adverse events compared with MS haemodynamics such as TMG and MVA in patients with combined AS and MS.

Left atrial strain by cardiac MRI feature tracking in mitral stenosis before and after balloon valvuloplasty.

The aim was to investigate LA strain by feature tracking cardiac MRI in mitral stenosis (MS) patients before and after percutaneous balloon mitral valvuloplasty (PBMV). Patients underwent cardiac MRI before and after successful PBMV (n = 18). Mitral valve area, transmitral velocity and gradients, LA volumes and ejection fraction (LAEF) were measured. LA strain feature tracking analysis was used to calculate LA reservoir, conduit, and booster strain. LA strain, LA volumes, LAEF and mitral valve severity indices were compared before and after PBMV. Correlations between LA strain and other cardiac MRI parameters were assessed. After PBMV, mitral valve area increased from 1.18 ± 0.25 cm2 to 2.26 ± 0.27 cm2, p < 0.001. Transmitral peak velocity decreased from 1.7 ± 0.37m/s to 1.3 ± 0.27m/s, p < 0.001. Transmitral peak gradient decreased from 12.4 ± 4.8 mmHg to 6.8 ± 2.9 mmHg, p < 0.001, and mean gradient decreased from 6.9 ± 3.8 mmHg to 2.9 ± 1.4 mmHg, p < 0.001. Maximal LA volume decreased from 73.1 ± 14.2 ml/m2 to 62.7 ± 16.3 ml/m2, p = 0.018; corrected p value = 0.054. LAEF increased from 36.3 ± 8.7% to 44.4 ± 9.5%, p = 0.010. Reservoir strain increased from 11.7 ± 3.1% to 14.9 ± 3.6% after PBMV, p = 0.009, and conduit strain from 3.8 ± 2% to 6 ± 2.3%, p = 0.005. Booster strain insignificantly increased after PBMV. Cardiac MRI feature tracking provides information on the 3 LA functional phases. Significant improvement was observed in reservoir and conduit functions after successful PBMV.

Mitral valve repair with leaflet resection versus preservation for degenerative posterior leaflet prolapse

ObjectivesThe optimal technique for repairing posterior mitral valve leaflet prolapse remains undetermined. We aimed to compare leaflet resection and neochordae implantation in patients undergoing mitral valve repair for posterior leaflet prolapse, focusing on transmitral pressure gradient and recurrence of mitral regurgitation. MethodsWe enrolled patients undergoing mitral valve repair using either leaflet resection or neochordae implantation for single-segment prolapse of posterior mitral valve leaflet between 2000 and 2021 at our institution. Longitudinal outcomes were evaluated after adjustments with inverse-probability-of-treatment weighting. Repeat echocardiographic measurements (n = 3473, 5.4/patient) of transmitral pressure gradient and significant (moderate or severe) mitral regurgitation recurrence were estimated using nonlinear mixed-effect models. Subgroup analyses were conducted based on the size and type of prosthesis. ResultsAmong 639 patients, leaflet resection was used in 479 (75.0%) and neochordae implantation was used in 160 (25.0%). In the inverse-probability-of-treatment weighting adjusted cohort, the risk of death (P = .623) and mitral valve reoperation (P = .340) did not significantly differ between the 2 groups during a median follow-up of 97.3 months. Echocardiographic data showed comparable mean (at 5 years, 3.8 vs 4.0 mm Hg; P = .442) and peak (9.6 vs 10.4 mm Hg; P = .131) pressure gradients between groups, which persisted in most subgroup analyses. However, neochordae implantation was associated with a higher probability of significant mitral regurgitation recurrence compared with leaflet resection (at 5 years, 16.1% vs 7.0%; P < .001). ConclusionsLeaflet resection yielded similar clinical outcomes and transmitral pressure gradients compared with neochordae implantation after mitral valve repair, with a lower mitral regurgitation recurrence rate. These findings underscore the need to reassess the efficacy of neochordae implantation relative to leaflet resection.

Invasive hemodynamic characteristics in patients with mitral annular calcification related mitral stenosis and chest radiation.

Quantification of invasive hemodynamics and mitral annular calcification-related mitral stenosis remains underexplored in patients exposed to chest radiation. We sought to explore invasive hemodynamic parameters via transseptal catheterization in patients with and without chest radiation who had a diagnosis of mitral annular calcification-related mitral stenosis. After excluding patients with more than moderate mitral regurgitation, we found that there was no difference in mitral valve area on hemodynamic testing in patients with and without radiation with an elevated baseline transmitral gradient on transthoracic echocardiography in the setting of mitral annular calcification-related mitral stenosis. There was a higher transmitral gradient and left atrial pressure in patients with prior radiation consistent with left atrial noncompliance, suggesting that treatment mitral valve stenosis may not relieve symptoms in this cohort of patients.

Efficacy and safety of trans-catheter repair devices for mitral regurgitation: A systematic review and meta-analysis

BackgroundSeveral repair strategies emerged as possible treatment for severe mitral regurgitation (MR). A systematic review and meta-analysis was performed to compare the different percutaneous mitral valve repair approaches. MethodsPubMed and Scopus electronic databases were scanned for eligible studies until December 11th, 2023. Clinical efficacy endpoints were all-cause mortality, major adverse cardiovascular events, and post-procedural NYHA functional class <3; the echocardiographic efficacy endpoint was a post-intervention residual MR less than moderate. Safety endpoints and procedural outcome measures were also assessed. ResultsEleven studies were included: 8 [N = 1662 patients, mean follow-up (FUP) 294 days] compared MitraClip® vs Pascal® device, 2 (N = 195 patients) MitraClip® vs Carillon® and 1 study (N = 186 patients) evaluated MitraClip® against Cardioband®. The Pascal®-treated group had lower MR degree compared to the MitraClip®-treated group, without difference in post-intervention mean trans-mitral gradient and in clinical and safety endpoints. A longer procedure time was observed in the Pascal® group, albeit with a lower average number of implanted devices per procedure. The two studies comparing MitraClip® and Carillon® were inconsistent in terms of both efficacy and safety outcomes, while the study evaluating MitraClip® vs Cardioband® showed that the latter might confer a significant clinical benefit, with a similar reduction in MR. ConclusionsPascal® is as safe and clinically effective as MitraClip® in treating patients with MR, with an apparent greater reduction in the magnitude of residual valve insufficiency over the long term. Data on Cardioband® and Carillon® are not robust enough to draw conclusions from the use of such devices.

Superiority of 3D planimetry over pressure half-time method for the assessment of mitral valve area after percutaneous edge-to-edge mitral repair

Introduction and objectivesThere is limited evidence to identify the most accurate method for measuring the mitral valve area (MVA) after percutaneous edge-to-edge mitral repair. Our objective was to evaluate the optimal method in this context and its correlation with the mean transmitral gradient. MethodsA registry of patients undergoing percutaneous mitral repair was conducted, analyzing different methods of measuring MVA and their correlation with the mean gradient. ResultsWe analyzed data from 167 patients. The mean age was 76±10.3 years, 54% were men, and 46% were women. Etiology was degenerative in 45%, functional in 39%, and mixed in 16%. Postclip MVA measurements were 1.89±0.60 cm2 using pressure half-time (PHT), 2.87±0.83 cm2 using 3D planimetry, and the mean gradient was 3±1.19mmHg. MVA using 3D planimetry showed a stronger correlation with the mean gradient (r=0.46, P<.001) than MVA obtained by PHT (r=0.19, P=.048). Interobserver agreement was also higher with 3D planimetry than with PHT (intraclass correlation coefficient of 0.90 vs 0.81 and variation coefficient of 9.6 vs 19.7%, respectively). ConclusionsOur study demonstrates that the PHT method significantly underestimates MVA after clip implantation compared with direct measurement using transesophageal 3D planimetry. The latter method also correlates better with postimplantation gradients and has less interobserver variability. These results suggest that 3D planimetry is a more appropriate method for assessing postclip mitral stenosis.

MITRACLIP TREATMENT FOR CARDIOGENIC SHOCK DUE TO ACUTE MITRAL REGURGITATION IN A PATIENT WITH POSTINFARCTION PAPILLARY MUSCLE RUPTURE

Abstract A 85–year–old woman presented to ED with worsening dyspnea for 24 hours; no other related symptom. Her medical history included hypertension, dyslipidemia, type 2 DM and surgical coronary revascularization 13 years before for multiple critical coronary artery disease (LIMA to LAD and sequential SVG to PDA and OM branch). The ECG promptly revealed a subacute infero–lateral STEMI. Transthoracic echocardiography (TTE) showed inferior and postero–lateral wall akinesia with severely reduced left ventricle ejection fraction (LVEF), mildly reduced right ventricle systolic function and severe mitral regurgitation (MR) due to posterior papillary muscle (PM) rupture (Fig.1). Clinical scenario was complicated by pulmonary edema and cardiogenic shock treated with diuretics and sodium nitroprusside infusion, non–invasive ventilation and IABP insertion. Urgent coronary angiography revealed a thrombotic occlusion of the venous graft for OM branch. Surgical correction was excluded due to hemodynamic instability. Graft occlusion was treated with manual thromboaspiration, balloon dilatations and abciximab infusion. After an initial stabilization, transesophageal echocardiography (TEE) was performed confirming severe MR resulting from rupture of one head of a bifid posterior PM (red arrows, Fig.1) and prolapse of the anterior leaflet combined with restrictive systolic movement of the posterior leaflet due to wall motion abnormalities. 3 days later a transcatheter mitral valve edge–to–edge repair (MTEER) was performed using a MitraClip device (1 XTR clip and 1 NTR clip, Fig.2). TEE with 3D and TrueVue vision confirmed the correct placement of clips (Fig.3), a mild–to–moderate residual MR, absence of significant transmitral gradient and a mildly reduced LVEF. No clinical events were reported during recovery; patient was discharged after 2 weeks. Conclusion MTEER is an established therapy for reducing degenerative and functional MR. Little data is available on its use in the setting of PM rupture. This rare complication of AMI carries a mortality rate of 80% during the first week without surgical correction but more than half of patients are excluded because of prohibitive operative risk. TEER may be an alternative for these patients. In this case report we described the utility of MTEER in the setting of cardiogenic shock secondary to acute ischemic MR with papillary muscle partial rupture. This procedure can be useful with acceptable safety and procedural success.

Percutaneous balloon mitral valvuloplasty with shockwave lithotripsy for the treatment of calcific mitral valve stenosis.

Calcific mitral stenosis (calcific MS) presents a challenge for surgical treatment and is a contraindication for most contemporary transcatheter mitral valve replacement devices (TMVR), rendering patients with very limited therapeutic options. This study aims to assess the clinical and hemodynamic follow-up after mitral valve lithotripsy (MVL). All consecutive patients who underwent MVL to treat symptomatic calcific MS at St Michael's Hospital, Toronto, Canada, were included. Patients were deemed unsuitable for mitral surgery or TMVR after heart team assessment. Patients with rheumatic MS or ≥moderate mitral regurgitation (MR) were excluded. The primary endpoint was a reduction in the invasive mitral gradient by ≥50% without significant (≥moderate) MR. Fifteen patients underwent MVL between 2021 and 2023 with a mean age of 74 ± 9 years; 53% were female, with a mean STS score of 10% ± 0.1%. Following MVL, there was a reduction in the invasively measured mean trans-mitral gradient compared to baseline (14 mmHg vs. 6 mmHg; p < 0.05). The primary endpoint was achieved in 8 patients (53%) with no major procedural complications. At follow-up (median 90 days, IQR 58-115 days), 14 (93%) patients reported improved symptoms from New York Heart Association (NYHA) Class III-IV to NYHA Class I-II (p < 0.01) with stable echo-derived mean gradient (7.7 mmHg ± 2 mmHg vs. 8.4 mmHg ± 2.9 mmHg (p = 0.7). In selected patients with symptomatic inoperable calcific MS, MVL was safe and associated with significant short-term clinical and hemodynamic improvement. MVL may represent a new compassionate therapy for this challenging cohort. Further studies are needed to determine the long-term outcomes and help define the role of IVL technology in treating calcific valvular conditions.

Superioridad de la planimetría 3D sobre el tiempo de hemipresión para evaluar el área valvular mitral tras la reparación mitral percutánea de borde a borde

Introduction and objectivesThere is limited evidence to identify the most accurate method for measuring the mitral valve area (MVA) after percutaneous edge-to-edge mitral repair. Our objective was to evaluate the optimal method in this context and its correlation with the mean transmitral gradient. MethodsA registry of patients undergoing percutaneous mitral repair was conducted, analyzing different methods of measuring MVA and their correlation with the mean gradient. ResultsWe analyzed data from 167 patients. The mean age was 76±10.3 years, 54% were men, and 46% were women. Etiology was degenerative in 45%, functional in 39%, and mixed in 16%. Postclip MVA measurements were 1.89±0.60 cm2 using pressure half-time (PHT), 2.87±0.83 cm2 using 3D planimetry, and the mean gradient was 3±1.19mmHg. MVA using 3D planimetry showed a stronger correlation with the mean gradient (r=0.46, P<.001) than MVA obtained by PHT (r=0.19, P=.048). Interobserver agreement was also higher with 3D planimetry than with PHT (intraclass correlation coefficient of 0.90 vs 0.81 and variation coefficient of 9.6 vs 19.7%, respectively). ConclusionsOur study demonstrates that the PHT method significantly underestimates MVA after clip implantation compared with direct measurement using transesophageal 3D planimetry. The latter method also correlates better with postimplantation gradients and has less interobserver variability. These results suggest that 3D planimetry is a more appropriate method for assessing postclip mitral stenosis.

Balloon mitral valvuloplasty in low gradient severe rheumatic mitral stenosis: Immediate and short-term outcomes

BackgroundEfficacy of balloon mitral valvuloplasty (BMV) in low gradient severe rheumatic mitral stenosis (MS) is not very well defined. This study was undertaken to evaluate the outcomes of BMV in low gradient severe rheumatic MS. MethodsSevere MS was defined as mitral valve area < 1.5 cm2. Low gradient was defined as mean diastolic trans-mitral gradient (MG) < 10 mmHg and low flow as stroke volume index < 35 ml/m2 on echocardiography. Sixty patients were divided into normal-flow/low-gradient (NFLG) (40) and low-flow/low-gradient (LFLG) (20) groups. Post-BMV parameters were recorded after 72 h and at the end of one year. ResultsMean age was 36.2 ± 6.6 years in NFLG group and 40.6 ± 2.6 years in LFLG group (p < 0.01) and females were 75 % (n = 30) in NFLG group as compared to 60 % (n = 12) in LFLG group. Patients in the LFLG group had higher Wilkins score (p < 0.02) and prevalence of atrial fibrillation (n = 8, 40 %) as compared to NFLG group (n = 7, 17.5 %; p < 0.01). A greater decrease in MG was observed in NFLG group (p < 0.01), whereas increase in MVA was comparable in both the groups (p > 0.05). Ninety percent (n = 36) patients improved in NFLG group in comparison to 70 % (n = 14) in LFLG group (p < 0.01). At the end of one-year, symptomatic improvement persisted in all patients who became asymptomatic post-BMV. ConclusionSymptomatic improvement following BMV was better seen in NFLG group because of greater decrease in MG in comparison to LFLG group. Results of BMV were suboptimal in LFLG group because of higher sub-valvular obstruction, increased age and higher prevalence of AF.

20-year follow-up of rheumatic mitral stenosis patients after percutaneous mitral commissurotomy: invasive transmitral gradient differential as a predictor of events.

Percutaneous mitral valve commissurotomy (PMC) is a viable alternative to mitral valve (MV) surgery in the treatment of patients with rheumatic mitral stenosis (RMS). In this single-center retrospective study of consecutive patients with RMS submitted to PMC from 1991 to 2008, we analyzed clinical, echocardiographic, and hemodynamic data and events during follow-up (FUP) until December 2021. Major adverse cardiovascular events (MACE) were a combined endpoint of all-cause death, cardiovascular hospitalization, and MV re-intervention. A total of 124 patients were enrolled: 108 (87.1%) were female, with a mean age at PMC of 46 [standard deviation (SD) 11] years. PMC was successful in 91.1%, with a mean reduction in invasive transmitral pressure gradient (TMPG) of 8 (SD 7) mmHg at PMC time. During the mean FUP of 20 (SD 6) years, 51 (41.1%) patients had MV re-intervention (86.3% surgery and 13.7% redo-PMC), 37 (29.8%) were hospitalized, and 30 (24.2%) died. Approximately 75% of patients remained MACE-free after 10 years, and this percentage decreased to around 40% after 20 years; at this time mark, about 8 in 10 patients were alive. A reduction of <5 mmHg in TMPG at PMC time was associated with a 2.7-fold greater rate of MACE compared to a reduction of ≥5 mmHg, independent of MV regurgitation after PMC and moderate disease of other valves (adjusted hazard ratio 2,7; 95% confidence interval 1.395-5.298, p=0.003). In this cohort with favorable long-term results after PMC, a reduction of <5 mmHg in TMPG at PMC time was associated with MACE during FUP. More studies are needed to validate this independent predictor.

Contemporary experience of mitral transcatheter edge-to-edge repair technology in patients with mitral annular calcification.

Mitral annular calcification (MAC) has been an exclusion for many of the earlier pivotal trials that were instrumental in gaining device approval and indications for mitral transcatheter edge-to-edge repair (M-TEER). To evaluate the impact of MAC on the procedural durability and success of newer generation MitraClip® systems (G3 and G4 systems). Data were collected from Northwell TEER registry. Patients that underwent M-TEER with third or fourth generation MitraClip device were included. Patients were divided into -MAC (none-mild) and +MAC (moderate-severe) groups. Procedural success was defined as ≤ grade 2 + mitral regurgitation (MR) postprocedure, and durability was defined as ≤ grade 2 + MR retention at 1 month and 1 year. Univariate analysis compared outcomes between groups. Of 260 M-TEER patients, 160 were -MAC and 100 were +MAC. Procedural success was comparable; however, there were three patients who required conversion to cardiac surgery during the index hospitalization in the +MAC group versus none in the -MAC group (though this was not statistically significant). At 1-month follow-up, there were no significant differences in MR severity. At 1-year follow-up, +MAC had higher moderate-severe MR (22.1% vs. 7.5%; p = 0.002) and higher mean transmitral gradients (5.3 vs. 4.0 mmHg; p = 0.001) with no differences in mortality, New York Heart Association functional class or ejection fraction. In selective patients with high burden of MAC, contemporary M-TEER is safe, and procedural success is similar to patients with none-mild MAC. However, a loss of procedural durability was seen in +MAC group at 1-year follow-up. Further studies with longer follow-ups are required to assess newer mTEER devices and their potential clinical implications in patients with a high burden of MAC.

Evaluation of Mean Mitral Gradient in Exercise Doppler Echocardiography in Mitral Stenosis

Background: In mitral stenosis (MS), the international recommendations are favor the mitral dilation if mean transmitral gradient reaches 15 mmHg or greater at the peak exercise Doppler echocardiography (grade C). Objective: Study of the transmitral gradient during exercise Echocardiography in patient with mitral valve area (MVA) of ≤ 2 cm². Results: 300 patients were included. The mean age was 42.7 ± 1.3 years, the sex ratio of 0.23. According to the MVA, three groups were defined. G1 (severe MS): MVA ≤ 1cm² (n =72), G2 (moderate MS): 1cm² &lt; MVA &lt; 1.5cm² (n = 128) and G3 (mild MS): MVA ≥ 1.5 cm² (n = 100). The mean MVA was 0.8 ± 0.1 cm² (G1), 1.3 ± 0.1 cm² (G2) and 1.7 ± 0.1 cm² (G3) (p &lt; 10-6). At rest, from the 1st to the 3rd group, mean heart rate/min was respectively 71.5 ± 2.7, 76.3 ± 1.7 and 73.6 ± 2.1, and means transmitral gradient were respectively to 11.6 ± 0.8 mmHg, 8.8 ± 0.5mmHg and 5.1 ± 0.3mmHg (p &lt; 10-6). At peak exercise, mean heart rate/min was 152.3 ± 2.9 (G1), 150.7 ± 2.2 (G2), 148.7 ± 2.4 (G3) (p = 0.20), and means transmitral gradient 39.2 ± 2.1 mmHg (G1), 31.5 ± 1.3 mm Hg (G2) and 22.8±1.0 mm Hg (G3) (p &lt; 10-6). At maximum of exercise, the mean transmitral gradient was above 15 mm Hg in 95 patients (95%) in group 3 despite MVA ≥ 1.5 cm². All patients of group 1 and group 2 increased their mitral gradient above 15 mm Hg at peak stress. Conclusion: At maximum exercise, most of our patients have increased their transmitral gradient beyond 15 mm Hg, even those who had mild MS (MVA ≥ 1.5 cm²). Therefore, in stress echo-Doppler, the mean mitral gradient at peak exercise justifying percutaneous valvulotomy is probably greater than 15 mm Hg.

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 effect of a smaller spacer in the PASCAL Ace on residual mitral valve orifice area.

Mitral transcatheter edge-to-edge repair (M-TEER) is an established treatment for functional mitral regurgitation (FMR) associated with a risk of creating iatrogenic stenosis. To investigate the impact of the P10 and its larger spacer compared to the narrower Ace and its smaller spacer on reduction of mitral valve orifice area (MVOA) during M-TEER. Consecutive patients undergoing M-TEER for treatment of severe FMR were screened retrospectively. Patients with a single PASCAL device implantation within the central segments of the MV leaflets, non-complex anatomy, and baseline MVOA ≥ 3.5cm2 were selected. Intraprocedural transesophageal echocardiography was used to compare MVOA reduction with 3D multiplanar reconstruction and direct planimetry. Device selection did not follow a prespecified MVOA threshold. Seventy-two patients (81.0 years, IQR {74.3-85.0}) were included. In 32 patients, the P10 was implanted (44.4%). MR severity (p = 0.66), MR reduction (p = 0.73), and body surface area (p = 0.56) were comparable. Baseline MVOA tended to be smaller in P10 patients with the larger spacer (5.0 ± 1.1 vs. 5.4 ± 1.3cm2, p = 0.18), however, residual MVOA was larger in these patients (2.7 ± 0.7 vs. 2.3 ± 0.6cm2, p = 0.03). Accordingly, relative MVOA reduction was significantly less in P10 patients (- 45.9 ± 7.6 vs. - 56.3 ± 7.0%, p < 0.01). Indirect annuloplasty was more pronounced in Ace patients whereas mean transmitral gradients were similar. In FMR patients with non-complex anatomy, the larger spacer of the P10 maintains greater MVOA with similar MR reduction. Hence, the use of the PASCAL Ace device in patients with small MVOAs might correlate with a risk of both clinically relevant orifice reduction and even iatrogenic stenosis.