Anterior Mitral Valve Leaflet Research Articles

Cardiovascular magnetic resonance insights into anomalies of the mitral valve apparatus in Fabry cardiomyopathy and hypertrophic cardiomyopathy.

Despite different etiopathogenesis, Fabry Disease cardiomyopathy (FDc) and sarcomeric hypertrophic cardiomyopathy (HCM) share a similar hypertrophic phenotype, including anomalies of the mitral valve apparatus (AMVA). Some of these anomalies have also been described in the pre-hypertrophic stage of both diseases. This cardiovascular magnetic resonance (CMR) study aimed to: (i) compare AMVA between FDc and HCM with a similar degree of left ventricular hypertrophy (LVH), to add new insights into differential diagnosis; (ii) assess whether AMVA represent an early and progressive alteration in FDc; (iii) propose simple and potentially reproducible measurements of AMVA. This observational, retrospective study enrolled: (i) 80 Fabry patients, divided into three groups with increasing severity of cardiac phenotype (20 patients LVH-/normal T1, 20 patients LVH-/low T1 and 40 patients LVH+), and (ii) 40 patients with HCM. All patients underwent CMR. The LVH + FDc and the HCM groups were matched for age, sex, body surface area and left ventricular (LV) mass. The following AMVA were measured on cine images: papillary muscles (PMs) hypertrophy (maximal diameter (Dmax) of anterolateral (Al) and posteromedial (Pm) PM), apical displacement, anteriorization of Al PM and anterior mitral valve leaflet (AMVL) elongation. Reference values for defining AMVA were derived from a matched healthy control group (n = 40). Both HCM and FDc LVH + patients showed PMs hypertrophy, with a greater degree in the FDc LVH + group [Dmax Al PM 16 ± 3.4 vs. 15 ± 3.1 mm, p 0.017; Dmax Pm PM 14 ± 4.0 vs.12 mm (10.0-14.0), p 0.039] As compared to controls, both HCM and FDc LVH + patients showed PMs apical displacement (HCM 83% vs. healthy volunteers 8%, p < 0.001; FDc LVH + 65% vs. healthy volunteers 8%, p < 0.001), with a greater prevalence in HCM. Anteriorization of Al PM was only evident in HCM (15 ± 6.2 vs. healthy controls 21 ± 5.3 mm, p < 0.001). Elongation of AMVL was detected both in HCM and FDc with LVH + (HCM 29 ± 4.0 vs. healthy volunteers 24 ± 2.9 mm, p < 0.001; FDc LVH + 27 ± 4.0 vs. healthy volunteers 24 ± 2.9 mm, p < 0.001) without significant differences between the two phenocopies. The prevalence of myocardial crypts was higher among HCM patients than in FDc LVH + patients (75% vs. 48%, p 0.012). we report greater PMs hypertrophy in FDc and a higher prevalence of PMs positional alterations (anterior and apical displacement) and myocardial crypts in HCM. All these AMVA became more pronounced with the progression of the FDc phenotype. We suggest the systematic inclusion of the analysis of AMVA by simple linear measurements on cine images in the CMR assessment of hypertrophic cardiomyopathies, to help in the differential diagnosis between HCM and FDc and to facilitate early detection of cardiac involvement in FDc.

Presentation of mitral valve cleft with concurrent atrial septal defect and ventricular septal defect detected by three-dimensional transesophageal echocardiography: a case report

BackgroundCleft in the mitral valve leaflet is a primary cause of congenital mitral regurgitation, stemming from developmental anomalies in the mitral valve and frequently associated with other congenital heart defects. Concurrent presence of cleft in mitral valve leaflet with atrial septal defect and ventricular septal defect is relatively rare. Echocardiography, especially transesophageal echocardiography, is essential in diagnosing cleft mitral valve leaflet and related congenital heart defects, providing critical, detailed imagery for accurate assessment. This study presents a young female patient whose anterior mitral cleft, along with atrial septal defect and ventricular septal defect, was revealed through three-dimensional transesophageal echocardiography.Case presentationA 25-year-old Iranian female, experiencing progressive dyspnea and diminished physical capacity over 3 months, was referred to our hospital. Initial examination and transthoracic echocardiography indicated severe mitral regurgitation. Further evaluation with transesophageal echocardiography corroborated these findings and identified a cleft in the anterior mitral valve leaflet, coupled with mild left ventricular enlargement and significant left atrial enlargement. The complexity of the patient’s condition was heightened by the diagnosis of cleft mitral valve leaflet in conjunction with atrial septal defect and ventricular septal defect, showing the complex nature of congenital defects.ConclusionThis case emphasizes the critical role of transthoracic echocardiography in diagnosing cleft of mitral valve leaflet and associated cardiac anomalies, showcasing its superiority over transthoracic echocardiography for detailed visualization of cardiac structures. The identification of multiple congenital defects highlights the necessity for a comprehensive diagnostic approach to manage and treat patients with complex congenital heart diseases effectively. Future research should aim to refine diagnostic methodologies to enhance patient outcomes for cleft of mitral valve leaflets and related congenital conditions.

Double trouble: an unusual case of Klebsiella pneumoniae invasive syndrome with liver abscess, gallbladder empyema and infective endocarditis

BackgroundKlebsiella pneumoniae invasive syndrome (KPIS) is characterized by primary pyogenic liver abscess associated with metastatic infections. Although rare, Klebsiella endocarditis carries a high mortality risk.Case presentationA 60-year-old lady with type II diabetes mellitus presented with fever, malaise, right hypochondriac pain and vomiting for two weeks. Ultrasound abdomen revealed a collection within liver, and distended gallbladder with echogenic debris within. 3 days after ultrasound guided pigtail drainage of gallbladder empyema, newly presence murmur detected. Pus, urine, and blood cultures obtained were positive for Klebsiella pneumonia. Echocardiogram exhibited oscillating mass attached to anterior mitral valve leaflet. After 6 weeks of intravenous ceftriaxone, follow-up echocardiogram and ultrasound showed complete resolution of mitral valve vegetation, hepatic and gallbladder collection.ConclusionConcomitant extrahepatic infective endocarditis (IE) should raise concerns in daily practice for patients with Klebsiella pneumoniae liver abscesses, despite the rarity of Klebsiella endocarditis. In the absence of diagnostic suspicion, antibiotic treatment regimens may be shortened, and adverse effects from IE infection may ensue.

Incidental Findings of Congenital Unileaflet Mitral Valves in Young Patient Presenting Complete Atrioventricular Block.

The singular leaflet mitral valve is a rare and complex entity that has been described in only a few case reports. It is commonly observed in infancy and combined with symptomatic mitral regurgitation (MR). In most asymptomatic individuals, this complication is attributed mainly to a hypoplastic posterior mitral leaflet and is usually revealed in adulthood. We present the case of a 30-year-old man who presented with chest pain and dyspnea for two days. The electrocardiogram showed complete atrioventricular block with a beat rate of 30 bpm.Echocardiography revealed an elongated anterior mitral valve leaflet and an almost completely absent posterior mitral valve leaflet with no MR. Our case is unusual presentation of a unileaflet mitral valve that should be investigated even in adulthood as these patients are likely to be at risk of developing or worsening MR later in life; hence, performing periodic echocardiograms is important for detecting the progression of MR early.

Mitral complex geometric changes aggravate mitral stenosis after transcatheter aortic valve replacement.

Severe aortic valve stenosis (AS) often coexists with mitral valve stenosis (MS). MS aggravation after transcatheter aortic valve replacement (TAVR) is common, and its etiology is multifactorial. We hypothesized that geometric changes in the mitral complex (mitral valvular and annular deformities) are adjunctive factors aggravating MS after TAVR, particularly in older adults with a smaller left ventricle (LV). This study aimed to evaluate the mitral complex geometric changes before and after TAVR and to assess the important predictors of MS aggravation after TAVR. This retrospective study enrolled consecutive adult patients who underwent TAVR and surgical AVR (SAVR) for severe AS. The mitral valve area (MVA), the angle between the anterior mitral valve leaflet (AMVL) and left ventricular outflow tract (LVOT), AMVL length, mitral annular diameter, presence of mitral annular calcification, and LV size were evaluated using transthoracic echocardiography. This study included 258 patients who underwent TAVR and SAVR. MVA index decreased from 2.3 ± 0.6cm² to 1.9 ± 0.5cm² in the TAVR group. The angle between the AMVL and LVOT was 56.3 ± 9.7° preoperatively and increased to 67.3 ± 11.5° after TAVR. In multivariate analysis, the most important predictive factors of MS aggravation after TAVR were a smaller mitral annular diameter, restricted AMVL mobility, and implantation depth (odds ratio: 4.5, 5.3,3.0; 95% confidence interval: 1.6-14, 1.9-17, 1.0-8.9; and p = 0.005, p = 0.001, p = 0.042, respectively). The reduction in MVA after TAVR was related to the restriction of AMVL opening, depth of implantation and narrowing of the mitral annulus.

Midterm Outcomes: A Comprehensive Approach to Surgery for Hypertrophic Obstructive Cardiomyopathy

BackgroundLeft ventricular outflow tract (LVOT) obstruction in obstructive hypertrophic cardiomyopathy (HCM) is caused by a constellation of abnormalities. This study reviewed outcomes of a comprehensive approach to correct these abnormalities during surgery. MethodsThis was a single-institution study of patients with HCM who underwent septal myectomy from 2016 to 2023. Their New York Heart Association functional classification and most recent echocardiogram that estimated LVOT gradient and mitral valve function were tracked. ResultsThe study included 103 patients with a mean age of 54 years (interquartile range, 40-67 years) and common comorbidities: hypertension (50%) and atrial fibrillation (25%). On average, the preprocedure resting echocardiogram showed an LVOT gradient of 36.4 mm Hg and moderate or severe mitral regurgitation in 50.5% of patients. All patients underwent septal myectomy, and associated abnormalities contributing to LVOT obstruction were addressed. Elongation of the anterior leaflet of the mitral valve was typically treated with papillary muscle realignment (72%). Aberrant papillary muscle heads and elongated secondary chordae tendineae contributing to systolic anterior motion were resected (66%). Myocardial bands, including apicoseptal bands contributing to LVOT obstruction, were resected (68%). With an average follow-up of 4 years, 91% of patients were considered to be in New York Heart Association functional class I or II. Long-term echocardiographic follow-up showed a mean peak LVOT gradient of 11 mm Hg (interquartile range, 4-13 mm Hg). Only 1 patient had more than mild mitral regurgitation. ConclusionsA comprehensive surgical approach to HCM that addresses the entire constellation of abnormalities associated with HCM, including mitral valve anterior leaflet elongation, aberrant or displaced mitral valve subvalvular apparatus, and myocardial bands, leads to outstanding midterm outcomes.

Changes in left ventricular-aortic angulation are associated with the development of obstruction in hypertrophic cardiomyopathy

ObjectiveTo characterize changes in ventricular morphology in patients with hypertrophic cardiomyopathy who develop left ventricular (LV) outflow tract obstruction. MethodsWe reviewed patients with hypertrophic cardiomyopathy with LV outflow tract obstruction who underwent septal myectomy from May 2012 to June 2023. Among 68 patients initially without obstruction documented up to 7.6 years (interquartile range, 6.3-9.4 years) before the operation, a comparison was made with 78 patients with nonobstructive hypertrophic cardiomyopathy over a similar period. Patients who did not develop obstruction were matched with those who did on sex, age, and maximum septal wall thickness during the initial echocardiography, identifying 41 matched pairs. Echocardiographic data, including 5 measures of angulation, were compared between the groups. ResultsThe median interval between echocardiographic assessments was 7.5 years (interquartile range, 6.3-8.1 years) among patients with obstruction versus 7.3 years (interquartile range, 6.2-9.0 years) in patients without nonobstruction. Patients with obstruction were more likely to have hypertension at both times. The maximum septal wall thickness increased within both groups (both P values < .001), but the magnitude of increase was not different between groups (P = .130). Patients with obstruction exhibited a greater increase in LV mass (P < .001) compared with patients without obstruction (P = .004). Aortic angulation significantly increased in 4 of the 5 measurements (all P values < .001) in patients with obstruction, whereas patients with no obstruction showed no change. Anterior and posterior mitral valve leaflet lengths and coaptation lengths remained similar in both groups over time. ConclusionsThe development of LV outflow tract obstruction in patients with hypertrophic cardiomyopathy was associated with progressive LV outflow tract angulation and increased LV hypertrophy, as reflected by LV mass. Progression to obstruction was not related to changes in the mitral valve leaflet morphology.

Application of Transcatheter Electrosurgery in Structural Heart Interventions: A Report of Three Different Techniques

Transcatheter electrosurgery is a novel technique to traverse or cut tissue, within blood-filled spaces, using alternating current directed by guidewires and catheters. We report the first series of transcatheter electrosurgery procedures in Asia including transcaval access for transcatheter aortic valve implantation, intentional aortic leaflet laceration to mitigate the risk of coronary occlusion in transcatheter aortic valve implantation and intentional laceration of anterior mitral valve leaflet to mitigate the risk of left ventricular outflow tract obstruction. These procedures are potentially valuable in Asian patients because of their smaller body build compared to Caucasians posing a higher risk of coronary or left ventricular outflow tract obstruction during transcatheter valve implantation. There is a need to adopt transcatheter electrosurgery in Asia to treat more surgically inoperable patients, including proper simulation training, bench training and clinical proctorship.

Improved Spatiotemporal Resolution in Echocardiography Using Mixed Geometry Imaging Sequences.

Cardiac ultrasound seeks to image the most dynamic environment in the body-the moving heart. Many modern ultrasound imaging techniques address the tradeoff between spatial and temporal resolution using either narrow focused beams or with broad beam, synthetic aperture (SA) sequences that have been shown to suffer from motion artifacts. Retrospective encoding for conventional ultrasound sequences (REFoCUS) unifies the processing of these various geometric sequences, but the motion sensitivity of this approach has yet to be investigated. We hypothesize that a "mixed sequence" enabled by the REFoCUS method incorporating several beam geometries may better resolve cardiac motion over a wide field of view (FOV) and at a high frame rate. First, the motion sensitivity of REFoCUS was evaluated in simulation for several focused and broad transmit profiles. Focused transmissions resolve both lateral and axial motion much more effectively than broad transmissions, with performance similar to conventional beamforming techniques. Second, a mixed sequence was designed that insonifies the full field-of-view with plane wave (PW) transmissions and key moving targets with focused transmissions. This mixed sequence was tested in simulation and in vivo and was used to image the heart as well as the liver, a low-motion control. By combining a sparse PW sequence ( n=60 ) with a small group of targeted focused transmissions ( n = 10), the anterior mitral valve leaflet (AML) at its peak observed velocity was better resolved. We believe that mixed sequences have strong potential to resolve cardiac motion at clinically relevant frame rates.

Differential Development of the Chordae Tendineae and Anterior Leaflet of the Bovine Mitral Valve.

There is increasing evidence that some adult mitral valve pathologies may have developmental origins involving errors in cell signaling and protein deposition during valvulogenesis. While early and late gestational stages are well-documented in zebrafish, chicks, and small mammalian models, longitudinal studies in large mammals with a similar gestational period to humans are lacking. Further, the mechanism of chordae tendineae formation and multiplication remains unclear. The current study presents a comprehensive examination of mitral anterior leaflet and chordae tendineae development in a bovine model (a large mammal with the same gestational period as humans). Remarkably distinct from small mammals, bovine development displayed early branched chordae, with increasing attachments only until birth, while the anterior leaflet grew both during gestation and postnatally. Chordae also exhibited accelerated collagen deposition, maturation, and crimp development during gestation. These findings suggest that the bovine anterior leaflet and chordae tendineae possess unique processes of development despite being a continuous collagenous structure and could provide greater insight into human valve development.

Radiofrequency Catheter Septal Ablation via a Trans-Atrial Septal Approach Guided by Intracardiac Echocardiography in Hypertrophic Obstructive Cardiomyopathy: One-Year Follow-Up.

Percutaneous radiofrequency catheter ablation (RFA) in hypertrophic obstructive cardiomyopathy (HOCM) with intracardiac echocardiography (ICE) guidance is a novel method that has been proven to be safe and effective in a small sample size study. RFA of the interventricular septum through a trans-atrial septal approach in HOCM patients with a longer follow-up has not been reported. 62 consecutive patients from March 2019 to February 2022 were included in this study. The area between the hypertrophied septum and anterior mitral valve (MV) leaflet was established using the three-dimensional system (CARTO 3 system), and all patients received atrial septal puncture under the guidance of intracardiac echocardiography (ICE). Point-by-point ablation was performed to cover the contact area. After ablation, the patients were followed up for 1, 3, 6, and 12 months. Transthoracic echocardiography was performed at 1, 3, 6, and 12 months, and resting and exercise-provoked left ventricular outflow tract (LVOT) gradients were obtained. During the 1-year follow-up, most patients' symptoms improved. The NYHA grading of the patient decreased from 2 (2, 3) at baseline to 2 (1, 2) (p 0.001). LVOT peak gradient at rest was decreased from 59 ( 27) mmHg to 30 ( 24) mmHg (p 0.001), and the provoked peak gradient was decreased from 99 ( 33) mmHg to 59 ( 34) mmHg (p 0.001). The average maximum septal thickness was reduced from 21 ( 4) mm to 19 ( 4) mm (p 0.001). After a 1-year follow-up, ice-guided radiofrequency ablation for HOCM might be a safe, accurate, and effective method. The catheter might be reliably attached to the ablation target area via trans-atrial septal access.

Echocardiographic assessment of morphofunctional and hemodynamic changes of rheumatic mitral valve dysfunction in the young. Morphological changes in rheumatic valve lesions

Background- Rheumatic fever and its sequel rheumatic heart disease remain a major health problem across the globe. This investigation aims to analyse the mitral valve morphofunctional changes, stratified by severity, and the magnitude of the mitral regurgitation and stenosis through a simplified echocardiographic scoring system in patients with rheumatic heart disease. Methods- As cross-sectional echocardiographic study was carried out in 98 consecutive patients with confirmed rheumatic heart disease. Patients undergoing outpatient clinical care over an 18-month period (mean follow-up period of 9,7±2,9 years) were selected for echocardiographic investigation. After a double-blind echocardiograms review, the inter-rater reliability was calculated (Kappa=0.875 (0.775- 0.974; CI 95%). The morphofunctional data of mitral apparatus were scored on a rating scale from one to fifteen, encompassing three categories (1-5: mild; 6-10: moderate; 10-15: severe) to quantify the degrees of severity. Pearson's Chi-squared test with Yates' continuity correction were performed for comparative analysis and the Wilcoxon test and the Cliff's Delta effect size was calculated to examine differences related to morphological features. Results- The majority of patients had rheumatic heart disease with clinical evidence and twenty patients (20,4%) had subclinical disease.The thickening of both mitral valve leaflets and the restrictive motion of the posterior leaflet were most frequently found in contrast with the low percentage of chordal and/or commissural fusion. The degree of the anterior mitral valve leaflet thickening was proportional to the magnitude of the mitral valve regurgitation (p=0.021). The higher degrees of mitral valve dysfunction were associated with more severe carditis (mitral valve regurgitation, p: 0.000; mitral valve stenosis, p: 0.031). No association was found between the severity of valvular lesions and patient age or length of the disease (p=0.320). The presence of beading was only observed in the acute phase (p=0,000); coaptation defect of the mitral valve was associated with significant left ventricle enlargement (p=0.000). The morphofunctional score of mitral apparatus, stratified by severity, was associated with the magnitude of mitral valve regurgitation (p=0,000) and of mitral valve stenosis (p=0,031) also quantified by severity. The highest scores were observed in patients with the most severe degrees of carditis (p=0,000); however, no association was found with either, the patients’ age (p=0.373) or the duration of the disease (p=0.361). Conclusions- In the analysis of severity of the mitral apparatus deformities and the resulting valve dysfunction, the morphofunctional score stratification was highly associated with the magnitude of mitral regurgitation and stenosis. In this young cohort, the higher scores were associated to severe carditis, but not to the patients’ age or the duration of the disease. Taking into account the low prevalence of severe valve dysfunctions, these results highlight the importance of early intervention and adequate prevention.

Outcomes of latent rheumatic heart disease: External validation of a simplified score in patients with and without secondary prophylaxis

BackgroundSecondary antibiotic prophylaxis reduces progression of latent rheumatic heart disease (RHD) but not all children benefit. Improved risk stratification could refine recommendations following positive screening. We aimed to evaluate the performance of a previously developed echocardiographic risk score to predict mid-term outcomes among children with latent RHD. MethodsWe included children who completed the GOAL, a randomized trial of secondary antibiotic prophylaxis among children with latent RHD in Uganda. Outcomes were determined by a 4-member adjudication panel. We applied the point-based score, consisting of 5 variables (mitral valve (MV) anterior leaflet thickening (3 points), MV excessive leaflet tip motion (3 points), MV regurgitation jet length ≥ 2 cm (6 points), aortic valve focal thickening (4 points) and any aortic regurgitation (5 points)), to panel results. Unfavorable outcome was defined as progression of diagnostic category (borderline to definite, mild definite to moderate/severe definite), worsening valve involvement or remaining with mild definite RHD. Results799 patients (625 borderline and 174 definite RHD) were included, with median follow-up of 24 months. At total 116 patients (14.5%) had unfavorable outcome per study criteria, 57.8% not under prophylaxis. The score was strongly associated with unfavorable outcome (HR = 1.26, 95% CI 1.16–1.37, p < 0.001). Unfavorable outcome rates in low (≤6 points), intermediate (7–9 points) and high-risk (≥10 points) children at follow-up were 11.8%, 30.4%, and 42.2%, (p < 0.001) respectively (C-statistic = 0.64 (95% CI 0.59–0.69)). ConclusionsThe simple risk score provided an accurate prediction of RHD status at 2-years, showing a good performance in a population with milder RHD phenotypes.

Successful Transcatheter Closure of Iatrogenic Mitral Regurgitation After Aortic Valve Surgery

We present 2 cases of significant mitral regurgitation secondary to pericardial patch avulsion from the anterior mitral valve leaflet after aortic valve replacement with aortic annulus enlargement. Both cases were successfully managed by transcatheter repair with off-label implantation of occluder devices.

Congenital Hypoplastic Mitral Valve Annulus: An Incidental Finding in a 30-Year-Old Male with Pericarditis

Introduction: Congenital malformation of mitral valve could encounter in isolation or with other congenital heart diseases. Objectives: Here, we report a case of congenital hypoplastic anterior mitral valve leaflet (AMVL). Methods: A 30-year-old male with a history of diabetes mellitus was referred with pleuritic chest pain since the previous day. He was admitted with impression of pericarditis. Trans thoracic echocardiography showed no pericardial effusion with incidental finding of lipomatous change of mitral valve annulus and hypoplastic AMVL with mild to moderate mitral regurgitation. Results: Cardiac magnetic resonance imaging showed thickening and fibrosis replacement of intervalvular fibrosa which extended to AMVL and resulted in restricted mitral valve annulus (12.4 mm) with subsequent restricted MV opening without significant mitral stenosis or regurgitation. These data were in favor of congenital hypoplastic MV annulus. Conclusions: Hypoplastic AMVL with restricted mitral valve annulus is a rare cause of mitral valve malformation and could be well tolerated since adulthood with good prognosis.

Aerococcus urinae infective endocarditis in a healthy young man: a case report

BackgroundAerococcus urinae infection is a rare clinical condition that causes urinary tract infections in older individuals. Infective endocarditis (IE) caused by A. urinae in healthy young men is extremely rare; however, the mortality rates of IE caused by A.urinae are high if appropriate surgical treatment is not performed.Case presentationA 39-year-old healthy man was admitted to our hospital with complaints of fever, cough, and dyspnea. Blood cultures revealed gram-positive cocci, and echocardiography revealed a 20 × 12-mm vegetation on the aortic valve and perforation of the anterior mitral valve leaflet. He was diagnosed with IE and underwent aortic valve replacement and mitral valve repair after removal of the infective focus. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry was used to identify A. urinae. The patient was discharged in good health after 6 weeks of ampicillin/sulbactam therapy.ConclusionPrompt diagnosis and surgical removal of infectious foci with optimal antibacterial therapy are critical to protect patients from rare and potentially fatal IE caused by A. urinae.

Transapical beating-heart septal myectomy for recurrent left ventricular outflow tract obstruction after septal reduction therapy in hypertrophic obstructive cardiomyopathy.

We present a case of a 58-year-old man for surgical myectomy due to recurrent left ventricular outflow tract (LVOT) obstruction, who had prior transaortic septal myectomy and embolization of the septal branch. On admission, transthoracic echocardiography showed a typical hypertrophic obstructive cardiomyopathy (HOCM) with asymmetric septal hypertrophy, significant LVOT obstruction, and severe mitral regurgitation (MR) due to the systolic anterior movement (SAM) of the anterior mitral valve leaflet. We performed a novel procedure of the transapical beating-heart septal myectomy (TA-BSM), following which the LVOT obstruction was resolved. And a decreased grade of SAM and a reduction in the severity of MR were observed.

Systolic anterior motion of the anterior mitral valve leaflet begins in subclinical hypertrophic cardiomyopathy.

Anterior mitral valve leaflet (AMVL) elongation is detectable in overt and subclinical hypertrophic cardiomyopathy (HCM). We sought to investigate the dynamic motion of the aorto-mitral apparatus to understand the behaviour of the AMVL and the mechanisms of left ventricular outflow tract obstruction (LVOTO) predisposition in HCM. Cardiovascular magnetic resonance imaging using a 1.5 Tesla scanner was performed on 36 HCM sarcomere gene mutation carriers without left ventricular hypertrophy (G+LVH-), 31 HCM patients with preserved ejection fraction carrying a pathogenic sarcomere gene mutation (G+LVH+), and 53 age-, sex-, and body surface area-matched healthy volunteers. Dynamic excursion of the aorto-mitral apparatus was assessed semi-automatically on breath-held three-chamber cine steady-state free precession images. Four pre-defined regions of interest (ROIs) were tracked: ROIPMVL: hinge point of the posterior mitral valve leaflet; ROITRIG: intertrigonal mitral annulus; ROIAMVL: AMVL tip; and ROIAAO: anterior aortic annulus. Compared with controls, normalized two-dimensional displacement-vs.-time plots in G+LVH- revealed subtle but significant systolic anterior motion (SAM) of the AMVL (P < 0.0001) and reduced longitudinal excursion of ROIAAO (P = 0.014) and ROIPMVL (P = 0.048). In overt and subclinical HCM, excursion of the ROITRIG/AMVL/PMVL was positively associated with the burden of left ventricular fibrosis (P < 0.028). As expected, SAM was observed in G+LVH+ together with reduced longitudinal excursion of ROITRIG (P = 0.049) and ROIAAO (P = 0.008). Dyskinesia of the aorto-mitral apparatus, including SAM of the elongated AMVL, is detectable in subclinical HCM before the development of LVH or left atrial enlargement. These data have the potential to improve our understanding of early phenotype development and LVOTO predisposition in HCM.

A Pilot Study Evaluating LV Diastolic Function with M-Mode Measurement of Mitral Valve Movement in the Parasternal Long Axis View.

This pilot study aimed to develop a new, reliable, and easy-to-use method for the evaluation of diastolic function through the M-mode measurement of mitral valve (MV) movement in the parasternal long axis (PSLA), similar to E-point septal separation (EPSS) used for systolic function estimation. Thirty healthy volunteers from a tertiary emergency department (ED) underwent M-mode measurements of the MV anterior leaflet in the PSLA view. EPSS, A-point septal separation (APSS), A-point opening length (APOL), and E-point opening length (EPOL) were measured in the PSLA view, along with the E and A velocities and e' velocity in the apical four-chamber view. Correlation analyses were performed to assess the relationship between M-mode and Doppler measurements, and the measurement time was evaluated. No significant correlations were found between M-mode and Doppler measurements in the study. However, M-mode measurements exhibited high reproducibility and faster acquisition, and the EPOL value consistently exceeded the APOL value, resembling the E and A pattern. These findings suggest that visually assessing the M-mode pattern on the MV anterior leaflet in the PSLA view may be a practical approach to estimating diastolic function in the ED. Further investigations with a larger and more diverse patient population are needed to validate these findings.

Exaggerated myocardial torsion may contribute to dynamic left ventricular outflow tract obstruction in hypertrophic cardiomyopathy.

Dynamic left ventricular (LV) outflow tract obstruction (LVOTO) is associated with symptoms and increased risk of developing heart failure in hypertrophic cardiomyopathy (HCM). The association of LVOTO and LV twist mechanics has not been well studied in HCM. The aim of the study was to compare the pattern of LV twist in patients with HCM associated with asymmetrical septal hypertrophy with and without LVOTO. Echocardiography (including speckle tracking) was performed in 212 patients with HCM, divided according to the absence (n = 130) or presence (n = 82) of LVOTO (defined as peak pressure gradient ≥30 mmHg either at rest and/or with Valsalva manoeuvre). Patients with LVOTO were older, had smaller LV dimensions, a higher LV ejection fraction (LVEF), a longer anterior mitral valve leaflet length, and a higher early transmitral pulsed wave to septal tissue Doppler velocity ratio (E/E'). A univariate analysis showed that peak twist was significantly higher in patients with LVOTO compared with patients without LVOTO (19.7 ± 7.3 vs. 15.7 ± 6.0, P = 0.00015). Peak twist was similarly enhanced in patients with LVOTO, manifesting only during Valsalva (19.2 ± 5.6, P = 0.007) and patients with resting LVOTO (19.9 ± 8.0, P = 0.00004) compared with patients without LVOTO (15.7 ± 6.0). A stepwise forward logistic regression analysis showed that LVEF, LV end-systolic dimension indexed to body surface area, anterior mitral valve leaflet length, E/E', and peak twist were all independently associated with LVOTO. This study demonstrates that increased peak LV twist is independently associated with LVOTO in patients with HCM. Peak twist was similarly exaggerated in patients with only latent LVOTO, suggesting that it may play a contributory role to LVOTO in HCM.