Aorto-mitral Angle Research Articles

Additional left atrial plication improves postoperative cardiovascular events in atrial functional mitral regurgitation.

Left atrial (LA) plication is a procedure used to correct an LA that expands posteriorly due to remodeling. This study aimed to determine the efficacy of additional LA plication in reducing postoperative cardiovascular events (CVEs) after mitral valve (MV) repair in atrial functional mitral regurgitation (MR) patients. Between October 2008 and August 2023, MV repair with or without LA plication in 74 patients was studied. This study examined the efficacy of concomitant LA plication during MV repair. All patients underwent mitral annuloplasty. Of these, 26 underwent additional LA plication. In the mid-term periods, protruding posterior LA length in patients with LA plication was shorter than those without LA plication (2.8±0.49 vs. 3.3±0.72 cm, P=0.01). The percentage change in aortomitral angle from preoperative to mid-term periods in patients with LA plication was bigger than those without LA plication (1.04°±0.102° vs. 0.98°±0.084°, P=0.01). Posterior leaflet coaptation angle in patients with LA plication was smaller than those without LA plication (42°±15° vs. 76°±30°, P<0.001). A postoperative posterior leaflet coaptation angle of 101° had the maximum sum of sensitivity and specificity in predicting postoperative CVEs (96.9% and 76.9%, respectively). Patients with a postoperative posterior leaflet coaptation angle of 101° or higher had a poorer prognosis than those with an angle less than 101°, with an event-free rate of 18% vs. 80% at 7 years after surgery (P<0.0001). Additional LA plication might be useful in reducing postoperative CVEs in atrial functional MR patients.

Efficacy and Outcomes of Para-Annular Plication in Mitral Valve Repair via Right Mini-Thoracotomy.

We aim to assess the efficacy and safety of left atrial plication (LAP), particularly para-annular plication, using a right mini-thoracotomy approach. Among 90 mitral valve repair (MVr) procedures performed at our institution between 2016 and 2023, 16 left atrial plication cases for left atrial enlargement (diameter: >50 mm) were assessed; nine cases underwent median sternotomy (conventional) (Group C), and seven cases underwent minimally invasive cardiac surgery (MICS) (Group M). The surgical protocol involved mitral valve repair via a right-sided left atrial approach, incorporating para-annular plication to suture the posterior wall. The mean follow-up duration was 3.3±2.4 years. Mortality within 30 days of surgery or during hospitalization did not occur. Postoperative complications included one case in each group that required reoperation for hemorrhage originating extraneously in the left atrium. Postoperative echocardiographic assessments revealed a comparable reduction in left atrial diameter (C/M: 80.3±7.0/80.7±14.6%; p=0.94), left atrial volume index (55.6±19.3/68.3±34.1%; p=0.36), and aorto-mitral angle (AMA) enlargement (113.8±7.3/107.5±12.2%; p=0.22). The three-year survival rate (88.9%/75.0%; p=0.33) was comparable between groups. The synergistic utilization of left atrial plication with para-annular plication via right mini-thoracotomy can enhance the postoperative outcomes of mitral valve repair.

Mitral Geometry on the Mechanism of Left Ventricular Outflow Tract Obstruction in Hypertrophic Cardiomyopathy

The mechanism of left ventricular outflow tract obstruction (LVOTO) is complex in hypertrophic cardiomyopathy (HCM). We aimed to evaluate the impact of mitral valve geometry on LVOTO by echocardiography. The study population comprised 177 consecutive patients with HCM. Morphological findings of left ventricular hypertrophy and LVOTO-related abnormalities were assessed by comprehensive transthoracic echocardiography. Aortomitral angle, mitral leaflet length, and coaptation height were measured and analyzed at rest. Multivariable stepwise forward logistic regression analysis was performed to identify geometric predictors of LVOTO. One hundred thirty-seven patients had an LVOT gradient ≥30mm Hg. Multivariable logistic regression showed that aortomitral angle (odds ratio [OR], 0.89; 95% CI, 0.83-0.95, P<.001), coaptation height (OR, 1.96; 95% CI, 1.41-2.72, P<.001), and accessory mitral valve chordae tendineae (OR, 13.1; 95% CI, 4.32-39.95; P<.001) were independently associated with LVOTO. Receiver operating characteristic analysis showed that the area under the curve of mitral coaptation height was higher (area under the curve=0.815) than the other 2 indicators (P<.05). Mitral coaptation height, aortomitral angle, and accessory mitral valve chordae tendineae were important predictors of SAM and LVOTO in HCM independent of septal hypertrophy.

High- versus low-gradient aortic stenosis: Is our evaluation limited by aorto-mitral angle on cardiovascular CT?

BackgroundAccurate assessment of aortic valve (AV) stenosis (AS) on transthoracic echocardiogram is crucial for appropriate clinical management. However, discordance between aortic valve area (AVA) and Doppler can complicate the diagnosis of severe AS in low-gradient (LG) AS phenotypes. MethodsWe reviewed 220 consecutive patients with suspected severe AS and AVA ≤1.0 cm2 on transthoracic echocardiogram who were evaluated for transcatheter AV replacement (TAVR) within a large health system from 2015 to 2019. We compared AV calcium score and aorto-mitral angle (AMA) on 3-chamber views from ECG-gated cardiovascular CT among patients with high-gradient (HG) AS (N = 19), paradoxical low-flow low-gradient (PLFLG) AS (N = 24) and normal-flow low-gradient (NFLG) AS (N = 14). ResultsAll groups had comparable age, comorbidities, and AV calcium scores. Compared to patients with HG AS (mean AMA 120 ± 10°), those with PLFLG AS (104 ± 12°; p < 0.001) and NFLG AS (106 ± 13°; p = 0.008) had narrower mean AMA values on cardiovascular CT. ConclusionLG AS patients have significantly narrower AMA than HG AS patients on cardiovascular CT. Due to difficulty obtaining parallel Doppler alignment, narrower AMA may contribute to AVA-Doppler discordance on echocardiogram. These findings emphasize the need for additional information in the setting of LG AS.

Quantitative Assessment of Three-Dimensional Aorto-Mitral Angle in Hypertrophic Cardiomyopathy

BackgroundThis study explored the correlation between the 3-dimensional aorto-mitral angle and pressure gradients in patients with obstructive hypertrophic cardiomyopathy (HCM) undergoing septal myectomy, with or without aortic shortening. MethodsA single-site, retrospective observational study was conducted at a tertiary-level hospital; 67 patients underwent septal myectomy for obstructive HCM. Preoperative and postoperative transesophageal images were analyzed offline to measure the end-systolic 3-dimensional aorto-mitral angle with Mitral Valve Quantification software and Doppler-derived pressure gradients. The angle’s impact on pressure gradients after myectomy, with or without aortic shortening, was evaluated by linear regression. ResultsRegression analysis found no significant relationship between aorto-mitral angle changes and postmyectomy pressure gradients (r = 0.03; 95% CI, −0.22 to 0.28; P = .81), regardless of aortic shortening. No major angle differences were observed between myectomy-only patients and those with additional aortic shortening (97.0° ± 8.4° vs 100.4° ± 8.7°; P = .78). ConclusionsThe reduced angle seen in patients with obstructive HCM did not return to normal values after septal myectomy, even with normalized pressure gradients. Aortic shortening did not significantly influence the aorto-mitral angle after myectomy either.

Relationship between mitral valve echocardiographic parameters and interventional septal reduction therapy success in patients with hypertrophic obstructive cardiomyopathy - a pilot study

Abstract Funding Acknowledgements Type of funding sources: None. Background The mitral valve (MV) has an important contribution to left ventricular outflow tract obstruction (LVOTO) in patients with hypertrophic obstructive cardiomyopathy (HOCM). Several parameters were described to be significantly different between obstructive and non-obstructive forms of HCM, like the aortomitral angle, anterior mitral leaflet (AML) and LVOT size, anterior displacement of the coaptation line, annular related parameters, etc. The redundant length of the AML beyond the coaptation point and the entire AML length are important in the decision to also approach the mitral valve when surgical septal reduction therapy (SRT) is considered, to increase the success rate. Data is scarce regarding mitral valve related predictors of interventional SRT response. This is important as certain patients have a suboptimal response regardless of the proper coronary anatomy and branch targeting. Purpose To evaluate the possible differences in certain mitral valve parameters in interventional SRT responders versus non-responders. Methods We retrospectively included in the study a number of 21 consecutive HOCM patients treated with alcohol septal ablation (ASA). All the procedures were guided with contrast echocardiography besides fluoroscopy and all patients had a proper distribution of at least 1 septal branch. They were divided in two groups- responder group (15 patients) with a non-significant residual LVOT PG (&amp;lt;50mmHg/&amp;gt;50% reduction) and non-responder group (6 patients) with a significant residual LVOT PG (&amp;gt;50mmHg/&amp;lt;50% reduction) and/or early rebound. We accounted for the residual LVOT PG evaluated by continuous Doppler at least 6 months after SRT. The groups were compared regarding LV dimensions and ejection fraction and mitral valve annulus/ leaflet size and displacement of the coaptation line, evaluated by bidimensional transthoracic echocardiography, before the intervention. Results The most hypertrophied part of the LV was the basal interventricular septum (IVS). The two groups were similar regarding age, comorbidities, LV dimensions and ejection fraction and baseline LVOT PG. Also, there was no significant difference between AML length, posterior mitral leaflet (PML) length, AML/PML, MV annulus. The redundant length of the AML was significantly lower in responders whereas anterior displacement of the coaptation point (projection of AML/projection of PML on the MV annulus) was less intense in responders and almost reached statistical significance. (Table) Interestingly, we found a baseline AML/PML projection &amp;lt;1 in all non-responder patients and only in 2 responder patients (13.33%) (p&amp;lt;0.001). Conclusion So far, significant anterior displacement of the coaptation point and the residual AML length may have an important impact on the response to ASA in HOCM patients. This pilot study could be an important start point for larger prospective studies to confirm and evaluated the prediction value of these parameters among others.

Anatomic considerations after commando double valve reconstruction: insights for future valve-in-valve therapies.

The Commando technique for reconstruction of the aortomitral intervalvular fibrous body is effective to facilitate double valve surgery in cases of endocarditis or infiltrative calcification. The length of patch utilized in reconstruction of the intervalvular fibrous body has an important relationship to the geometry of the mitral valve (MV) and aortic valve (AV) and may impact on potential future valve-in-valve (VIV) therapy. Here we report anatomic measurements after Commando reconstruction in a small group of patients and analyse the impact of reconstruction techniques on transcatheter VIV therapies. Seven patients from January 2018 to April 2022 who underwent double valve surgery with the Commando technique with postoperative computed tomography (CT) scans were identified. Computed tomographic reconstruction of the AV and MV was performed using 3mensio software and virtual transcatheter valve replacement was performed. Two of these patients who had preoperative imaging was analysed to assess the change in aortomitral geometry resulting from reconstruction. Measurements for each patient post-reconstruction are given in the table. Aortomitral length was grossly inversely proportional to aortomitral angle (AMA). AMA and aortomitral curtain (AMC) length were significantly altered post-Commando in 2 analysed patients with pre- and postoperative computed tomography scan. Transcatheter AV and MV replacements were feasible in all patients post-Commando. The AMA was larger and more favorable for mitral VIV in patients in which the AMC was short. AMC length, as determined by location of AV annular sutures, may be an important consideration in surgical decision-making for VIV after the Commando procedure.

Systolic Anterior Motion of the Mitral Valve in the Presence of Annular Calcification

Mitral annular calcification (MAC) has been reported as a possible cause of systolic anterior motion (SAM) of the mitral valve and dynamic left ventricular outflow tract (LVOT) obstruction. While morphologic features predisposing to SAM in other clinical settings have been described, patients with MAC+SAM have not been systematically investigated. We hypothesized that bulky calcium deposits in the mitral annulus could displace the valve toward the septum, thus promoting development of SAM. We studied 30 patients with severe MAC who had SAM with septal contact. Three comparator groups (matched for age and sex) were developed: 30 controls without MAC or SAM, 30 with severe MAC but no SAM, and 30 with SAM but no MAC. Significant differences were found across groups for mitral valve coaptation point-septal distance (CSD), anterior mitral leaflet (AML) length, left ventricular diastolic dimension, and ejection fraction. Comparing all MAC subjects (n=60) with controls, CSD was less (20.5±4.1 vs 23.2±3.7mm, P=.003) and ejection fraction was higher (67.7%±7.8% vs 60.9%±6.4%, P<.0001) in MAC patients. Within MAC subjects AML was longer (21.9±3.0 vs 17.4±2.2mm, P<.0001) and CSD was smaller (18.0±2.7 vs 23.1±3.6mm, P<.0001) when SAM was present despite similar height of the calcium bar in the 2 MAC groups (12.4±2.9 vs 11.1±3.1mm, P=.11). Regression analysis confirmed AML length and CSD as independent predictors of SAM. MAC+SAM patients also had more echocardiographic risk factors for SAM (acute aortomitral angle, small LVOT, long AML, small CSD, and presence of a septal bump) than MAC/no-SAM patients (3.4±0.9 vs 1.8±1.0, P<.0001). Bulky MAC appears to contribute to dynamic LVOT obstruction when it accumulates in such a way that the mitral valve is displaced anteriorly toward the septum. However, other features are also associated with SAM in these patients, particularly a long AML. A combination of morphologic features and favorable hemodynamics may be needed for SAM to develop in patients with severe MAC.

Level of agreement between three-dimensional transthoracic and transesophageal echocardiography for mitral annulus evaluation: A feasibility and comparison study.

Mitral annulus assessment is of utmost importance for the management of patients with mitral valve (MV) abnormalities, as it helps to determine the decision for surgical or transcatheter treatment. Three-dimensional (3D) transesophageal echocardiography (TOE) has been the only reliable echocardiographic method for the evaluation of the mitral annulus by now. However, newer transthoracic echocardiography (TTE) 3D probes have enabled to provide accurate measurements as well and become a valuable tool when TOE is contraindicated. The aim of this study is to assess the feasibility of 3D TTE analysis of mitral annulus and the level of agreement with 3D TOE measurements. A total of 121 consecutive patients were assessed with 3D TTE and TOE. All mitral annulus parameters were retrospectively analyzed with the dedicated 4D autoMVQ application. Bland-Altman analysis and intraclass correlation coefficient were used for the comparison and agreement between the two methods. Half of our patients had normal mitral valves and served as control group, while the other half had various mitral valve pathologies. AutoMVQ analysis was not feasible in 11 out of 121 TTE examinations (91% feasibility) and in 4 out of 121 TOE examinations (96% feasibility). Mitral annular area and perimeter were slightly larger in TTE than those measured by TOE (12.7±3.6vs. 12.4±3.2 cm2 for area and 12.7±1.7vs. 12.5±1.6cm for perimeter), however still showing strong correlation (r=.942 and r=.922, respectively). The majority of mitral valve measurements (anterior-posterior, medial-lateral and commissural diameter, aorto-mitral angle and anterior leaflet length) were similar among the two methods with strong correlation (r>.80). Inter-trigonal distance, posterior leaflet length and tenting height showed weaker agreement between TTE and TOE (r=.687, r=.687, r=.634, respectively). Mitral annular dimensions (by 3D area) were found to be significantly larger in patients with MV pathology (13.5±3.5vs. 11±2.3 cm2 ), atrial fibrillation (14.4±3vs. 11.4±2.8 cm2 ), left ventricular (13.8±3.1vs. 11.7±3.1cm2 ) and left atrial dilatation (13±3.3vs. 10.6±2.3cm2 ) compared to the individuals in the control group (p<.001 for all comparisons). Assessment of the MV with 3D TTE with dedicated MVQ software is feasible and accurate, showing strong correlation and agreement with TOE measurements.

The Critical Biomechanics of Aortomitral Angle and Systolic Anterior Motion: Engineering Native Ex Vivo Simulation.

Systolic anterior motion (SAM) of the mitral valve (MV) is a complex pathological phenomenon often occurring as an iatrogenic effect of surgical and transcatheter intervention. While the aortomitral angle has long been linked to SAM, the mechanistic relationship is not well understood. We developed the first ex vivo heart simulator capable of recreating native aortomitral biomechanics, and to generate models of SAM, we performed anterior leaflet augmentation and sequential undersized annuloplasty procedures on porcine aortomitral junctions (n = 6). Hemodynamics and echocardiograms were recorded, and echocardiographic analysis revealed significantly reduced coaptation-septal distances confirming SAM (p = 0.003) and effective manipulation of the aortomitral angle (p < 0.001). Upon increasing the angle in our pathological models, we recorded significant increases (p < 0.05) in both coaptation-septal distance and multiple hemodynamic metrics, such as aortic peak flow and effective orifice area. These results indicate that an increased aortomitral angle is correlated with more efficient hemodynamic performance of the valvular system, presenting a potential, clinically translatable treatment opportunity for reducing the risk and adverse effects of SAM. As the standard of care shifts towards surgical and transcatheter interventions, it is increasingly important to better understand SAM biomechanics, and our advances represent a significant step towards that goal.

Aortomitral angle affects cardiovascular events after mitral valve repair for atrial functional mitral regurgitation.

This study aimed to elucidate the geometric parameters of the aortomitral (AM) complex affecting postoperative cardiovascular events (CVEs) in patients with atrial functional mitral regurgitation (MR). From October 2008 to August 2018, we performed mitral and tricuspid valve repairs in 58 patients with atrial functional MR. We examined the determinants of CVEs using preoperative and postoperative echocardiographic data. Furthermore, we analyzed the effect of left atrial (LA) plication on AM geometries after surgery. The follow-up period ranged from 56 to 3283 days (median, 1073 days). All patients underwent mitral and tricuspid annuloplasty. Seventeen patients (29%) underwent additional LA plication. The AMangle was narrowed after surgery in patients with CVEs (115° ± 6.8° to 106° ± 4.2°, p = .00336), whereas it widened in patients without CVEs (115° ± 7.4° to 118° ± 8.4°, p = .0278). The postoperative AM angle was an independent predictor of postoperative CVEs (p = .000829). LA plication was not a predictor of CVEs; however, it was a predictor of the obtuse postoperative AM angle (p = .0071). Our results suggest that a narrow postoperative AM angle is an independent predictor of postoperative CVEs. Additional LA plication reduces the sharpening of the AM angle, which may prevent CVEs after mitral valve repair for atrial functional MR.

The Impact of Aorto-Mitral Angle on New-Onset Atrial Arrhythmia after Mitral Valve Repair in Patients with Mitral Regurgitation.

In this study, we hypothesized that post-operative aorto-mitral angle might be associated to the occurrence of post-operative atrial arrhythmia (AA), including atrial fibrillation and atrial tachycardia, after mitral valve repair in patients with mitral regurgitation (MR). Thus, this present study aims to determine the effects of post-operative aorto-mitral angle on new-onset AA after mitral valve repair with mitral annuloplasty for the treatment of MR.In total, 172 patients without any history of AA underwent mitral valve repair with mitral annuloplasty in our institution between 2008 and 2017. Patient information, including medical records and echocardiographic data, were retrospectively studied.As per our findings, AA occurred in 15 (8.7%) patients during the follow-up period (median, 35.7 months; range, 0.5-132 months). The patients with AA were noted to have a longer cardiopulmonary bypass time and a smaller aorto-mitral angle at post-operative TTE than the others (119 ± 6° versus 125 ± 10°, P = 0.003). No significant difference was noted in the degree of post-operative residual MR or functional MS between the groups. In a multivariate Cox proportional hazards analysis, the longer cardiopulmonary bypass time and the smaller post-operative aorto-mitral angle were independent predictors of the occurrence of AA during the follow-up period (odds ratio per 10 minutes 1.11; 95% CI 1.02-1.22, P = 0.019: odds ratio 0.91; 95% CI 0.85-0.98, P = 0.012).A small aorto-mitral angle at post-operative TTE was determined to be a predictor of new-onset AA after a mitral valve repair for treating MR.

Systolic anterior motion of the mitral valve associated with acute type A aortic dissection: a case report describing one-step surgery of ascending aortic replacement and interventricular septal myectomy

BackgroundSystolic anterior motion of the mitral valve associated with acute type A aortic dissection is rare in daily clinical practice. The prevention of systolic anterior motion is important, because once it occurs, the hemodynamics may become unstable, leading to a critical situation. In the surgical procedure to treat systolic anterior motion, the prevention of new iatrogenic aortic intimal tears is important in the context of acute type A aortic dissection.Case presentationWe present a case of systolic anterior motion in a 68-year-old woman with an acute type A aortic dissection and suspected acute relative adrenal insufficiency. Preoperative transthoracic echocardiography revealed left ventricular outflow tract obstruction due to systolic anterior motion without left ventricular hypertrophy and interventricular septal bulging due to a narrow aorto-mitral angle. We successfully performed a one-step surgery for ascending aortic replacement and interventricular septal myectomy using the needle stick technique for the treatment of systolic anterior motion.ConclusionsConcomitant interventricular septal myectomy using the needle stick technique with thoracic aortic replacement is a safe and feasible technique. Interventricular septal myectomy may be effective in preventing postoperative unstable hemodynamics due to systolic anterior motion in the management of acute aortic dissection.

Left ventricular outflow tract area after percutaneous transseptal transcatheter mitral valve implantation: A three‐dimensional transesophageal echocardiography study

Left ventricular (LV) outflow tract (LVOT) obstruction increases mortality in patients undergoing transcatheter mitral valve implantation (TMVI) in degenerated bioprostheses, annuloplasty rings, and native mitral valves. We aimed to evaluate the LVOT area after TMVI using 3-dimensional (3D) transesophageal echocardiography (TEE) and to investigate the preprocedural cardiac geometry that affects the LVOT area after TMVI. We retrospectively reviewed echocardiography data in 43 patients who had TMVI. A change in pressure gradient across LVOT from before to after TMVI (∆PG) and postprocedure 3D LVOT cross-sectional area at the level of the most distal portion of the mitral valve stent that was closest to the LV apex were assessed as evidence of LVOT narrowing. Transcatheter mitral valve implantation with the use of balloon-expandable valve system was performed for 24 bioprostheses, 7 annuloplasty rings, and 12 native valves. Compared to patients without increase in LVOT gradient (∆PG <10mm Hg; n=33), patients with increase in LVOT gradient (∆PG ≥10mm Hg; n=10) had smaller LV end-systolic volume (LVESV), greater LV ejection fraction (LVEF), and smaller aorto-mitral (AM) angle. The LVOT area at the valve stent distal edge showed strong association with ∆PG (r=-.68, P<.0001). Only a small AM angle was associated with a small LVOT area at the valve stent distal edge on multivariable analysis, independent of LVESV and LVEF. Small LV size, preserved LVEF, and small AM angle were associated with LVOT narrowing. 3D-derived AM angle might be independently associated with LVOT narrowing in patients undergoing transcatheter mitral valve-in-valve, valve-in-ring, and valve-in-native valve implantation, independent of LVESV and LVEF.

Effects of combined myectomy with mitral valve repair on a three-dimensional mitral valve model and left ventricle outflow obstruction in patients with hypertrophic cardiomyopathy

Aim . To assess the effects of combined myectomy with mitral valve repair on a three-dimensional model of the mitral valve in patients with obstructive hypertrophic cardiomyopathy. Methods. 24 patients with obstructive hypertrophic cardiomyopathy and left ventricular outflow obstruction over 50 mm Hg at rest were recruited in a study. Eight patients underwent combined myectomy with mitral valve repair according to the Carpentier method. Seven patients underwent the Alfieri's edge-to-edge repair, and nine patients underwent secondary chordae resection using the Ferrazzi’s technique. Before combined myectomy and two weeks after it, all patients underwent standard transthoracic echocardiography and real-time 3D transesophageal imaging of the mitral valve, followed by quantitative 3D reconstruction of the mitral valve and calculation of the annulus, the leaflets, and the aorto-mitral angle. Results. Despite the selected mitral valve repair technique, we observed a decrease in the LVOT obstruction gradient. There were no differences in the residual obstruction gradient between the selected mitral valve repair technique. Patients with obstructive hypertrophic cardiomyopathy, who underwent combined myectomy and posterior mitral leaflet plasty valve according to the Carpentier approach, reported a correlation of a decrease in the LVOT obstruction with the non-planar angle (r = -0.83; p = 0.040), sphericity index (r = 0.83; p = 0.04) and a decrease in the velocity excursion of the annulus (r = 0.94; p = 0.005). Patients who underwent the Alfieri's edge-to-edge repair demonstrated that the residual LVOT obstruction gradient depended on the annulus height (r = 0.90; p = 0.04) and the ratio of this height to the commissural diameter of the annulus ( r = 0.90; p = 0.04). After secondary chordae resection, a decrease in the LVOT obstruction gradient correlated with the sphericity index (r = 0.77; p = 0.03), the anterolateral-posteromedial annulus diameter (r = -0.72; p = 0.04), the anterior (r = -0.78; p = 0.02) and posterior (r = -0.78; p = 0.02) leaflets, the ratio of the total leaflet length to the anteroposterior diameter of the annulus (r = -0.83; p = 0.01), the area (r = -0.76; p = 0.0з) and the mitral valve tenting height (r = -0.95; p = 0.00). Conclusion .Combined myectomy with mitral valve repair is the method of choice in the treatment of patients with obstructive hypertrophic cardiomyopathy. The comparison of three mitral valve repair techniques did not reveal any differences in the residual LVOT obstruction gradient. However, the Alfieri's edge-to-edge repair may be considered as the most physiological technique to repair dynamic LVOT obstruction.

Abstract 17070: Engineering a Novel Ex Vivo Heart Simulator for Biomechanical Analysis of the Aortomitral Junction

Introduction: Advances in ex vivo heart simulation have enabled the study of valvular biomechanics, disease pathologies, and repair strategies. However, these simulators test the valves in isolation, which does not fully replicate in vivo physiology. We hypothesize that by engineering a simulator that preserves the aortomitral junction, we can better recreate pathophysiologies such as systolic anterior motion (SAM). Here, we present a new heart simulator that preserves and manipulates the native aortomitral physiology. Methods: Our simulator is comprised of three subsystems: the ventricular chamber, atrial chamber, and aortic chamber (Fig A, B). The heart is excised at the apex to preserve the papillary muscles, and the left ventricle, atrial cuff, and aorta are fixed to their respective chambers via hemostatic suturing to 3D-printed elastomeric rings. The chambers are equipped with pressure and flow sensors, and a linear piston pump generates physiologic pressures and flows. The atrial and aortic chambers are mounted on 5-degree-of-freedom arms. To demonstrate system function, we manipulated the aortomitral angle and measured aortic cardiac output. Results: In our testing, we evaluated two unique configurations of an explanted porcine heart, of which the aortomitral angles spanned the SAM predictive risk threshold of &lt;120° (Fig C, D). From the flow readings, we measured a 36% reduction in aortic cardiac output upon decreasing the aortomitral angle by 25°. Conclusions: This work highlights the design and development of an ex vivo heart simulator capable of modeling native aortomitral physiology. Our results point to a clear direction for future experimentation, particularly evaluating the biomechanical changes of the heart based on the aortomitral angle. Future work will utilize this platform to create new models and repair techniques to ultimately improve clinical care of valvular pathologies.

Acute changes in mitral valve geometry after MitraClip procedure assessed by 3D transoesophageal echocardiography

Abstract Background MitraClip procedure is a treatment option in patients with symptomatic mitral regurgitation (MR) and prohibitive surgical risk. Echocardiographic evaluation of mitral valve (MV) is of paramount importance for the correct identification of patient eligibility and procedural success. Our aim is to assess the acute effect of device implantation on mitral annular geometric parameters still little explored with the use of three-dimensional (3D) transoesophageal echocardiography (TEE) and to investigate its relationship with residual MR at discharge. Methods 67 consecutive patients (mean age78.7±7.2 yrs, 41 males) undergoing percutaneous MV repair with MitraClip in our Centre were enrolled. Patients eligibility was evaluated according to the EVEREST criteria and current guidelines. Four groups were identified on the base of MR aetiology: 22 were degenerative (DMR), 19 ischemic functional (IFMR), 19 non-ischemic functional (NIFMR) and 7 atrial functional (AFMR). 3D TEE was performed before and immediately after clip deployment with MV anatomical quantification by PHILIPS® QLAB MVQ and GE® 4D-AUTO-MVQ software. Results Severe MR (4+) was found in 17 pts, and moderate-severe MR (3+) in 50 pts. Thirteen cases were unsuccessful because of unchanged or residual MR&amp;gt;2+. Immediately after device positioning, almost all the evaluated parameters showed a significant modification within each group with a reduction of anterior-posterior (AP-D) and bi-commissural (CC-D) MV diameters, MV annulus area and perimeter and an increase in tenting volume, tenting height and posterior mitral leaflet angle (PML α). Anterior mitral leaflet angle (AML α), sphericity index and aorto-mitral angle remained unchanged. We observed no significant difference in the sub-analysis between degenerative and all functional MR groups, although a different trend of parameters variation could be evidenced. Post-procedural tenting height with cut off of 5.5 mm was a predictor of procedural success (see fig.), while at univariate analysis basal AP-D in DMR group and sphericity index, PMLα and annulus height at baseline in the FMR group were all significantly correlated to the entity of MR reduction at discharge. Conclusions Percutaneous edge-to-edge repair with MitraClip acutely changes the MV annular geometry in degenerative and both ventricular and atrial functional MR, with a different trend within each group. Post-procedural tenting height correlates with significant MR reduction at discharge, a promising marker that could be used in clinical practice for identification of MitraClip procedure success. Funding Acknowledgement Type of funding source: None

Transcatheter mitral valve in ring, hazards of long anterior mitral leaflet and 3-dimensional rings.

The purpose of this study was to define anterior mitral leaflet (AML) length and mitral ring characteristics associated with LVOT obstruction and PVL following MViR. Transcatheter Mitral Valve in Ring (MViR) procedural complications including parvalvular leak (PVL) and left ventricular outflow tract (LVOT) obstruction are frequent. Clinical records, computer tomographic scans (CTs) and echocardiograms of consecutive MViR patients were retrospectively reviewed for anterior mitral leaflet length, CT-simulated neoLVOT, and aortomitral angle among patients with and without MViR-induced LVOT obstruction. Acute and 1-year outcomes are described. Twenty-two patients underwent MViR. Technical success was achieved in 13/22 (57.1%) patients, limited by paravalvular regurgitation requiring second transcatheter heart valves (THVs) in seven patients. Second valves were needed in 6/11 (54.5%) patients with 3-dimensional rings but 1/11 (9.1%, p = .06) of patients with planar rings. Procedure success at 30 days was achieved in 20/22 (90.9%) patients. There were no procedural, in-hospital, or 30-day deaths. Two patients developed significant LVOT obstruction, one managed with urgent surgery and one with elective alcohol septal ablation. Anterior mitral leaflets were longer among the two patients with LVOT obstruction than the 20 patients who did not develop LVOT obstruction when measured by TEE (30 mm vs. 21 mm, p = .009) or by CT (29 mm vs. 22 mm, p = .026). AML >25 mm increases the risk of MViR induced LVOT obstruction. PVL is common, particularly in 3-dimensional rings which can be managed with a second THV.

Computed Tomography-based evaluation of porcine cardiac dimensions to assist in pre-study planning and optimized model selection for pre-clinical research

The pig (Sus Scrofa Domestica) is an accepted model for preclinical evaluation of prosthetic heart valves and trans-catheter implantation techniques. Understanding porcine cardiac dimensions through three-dimensional computed tomography (CT), increases preclinical study success, leading to higher cost efficiency and to the observance of the obligation to the 3 R principles. Cardiac CT images of twenty-four Swiss large white pigs were segmented; aortic root, mitral valve, pulmonary trunk, tricuspid valve, as well as the aorto-mitral angle and left atrial height were analyzed. Correlation coefficient (r) was calculated in relation to body weight. In Swiss large white pigs, valvular dimensions, length of the pulmonary artery and ascending aorta as well as left atrial height correlate with body weight. Coronary ostia heights and aorto-mitral angle size can be neglected in animal size selection; no changes were found for either of the two parameters with increasing body weight.

Mitral valve in hypertrophic cardiomyopathy: a three-dimensional transesophageal study

BackgroundIt is reported that the mitral valve (MV) in hypertrophic cardiomyopathy (HCM) has structural abnormalities. PurposeTo assess the MV in HCM patients using Three-Dimensional Transesophageal Echocardiography (3DTEE). MethodsTransthoracic and 3DTEE studies focused on the mitral valve were performed prospectively in 21 HCM patients with obstruction (Group I), 37 HCM patients without obstruction (Group II) and 28 controls (Group III). ResultsThe aortomitral angle was less obtuse in groups I and II compared with group III (104.6 ± 6.7° vs 107.6 ± 8.5° vs 112.9 ± 3.2°, p < 0.001) and the annulus height was larger (11.6 ± 1.3 mm vs 11.6 ± 2 mm vs 9.3 ± 1.1 mm, p < 0.001). Patients in group I compared with groups II and III had increased ratio of anterior leaflet length to left ventricular outflow tract (LVOT) diameter (1.9 ± 0.1 vs 1.7 ± 0.3 vs 1.3 ± 0.1, p < 0.05) and anterior displacement of the coaptation line as showed by the reduced ratio of anterior to posterior leaflet length in the projection plane (1.7 ± 0.4 mm vs 2.2 ± 0.7 mm vs 2.4 ± 0.7 mm, p < 0.05). In groups I and II there was a positive correlation between the MV annulus height and the presence of non-sustained ventricular tachycardia (rs = 0.25, p < 0.05). ConclusionThe MV in HCM patients with or without obstruction shares some common anatomic features. Additionally, the MV in patients with obstruction has unique characteristics that appear to contribute to LVOT obstruction.