scholarly journals The role of subvalvular structures in the development of mitral valve prolapse in children

2012 ◽  
Vol 93 (3) ◽  
pp. 490-493
Author(s):  
Yu M Belozerov ◽  
Sh M Magomedova ◽  
Z S Abakarova ◽  
I M Osmanov

Aim. To assess the role of subvalvular structures in the development of mitral valve prolapse in children. Methods. Conducted was an echocardiography investigation with comparative analysis of structural and functional parameters of subvalvular structures in healthy children (50 individuals) and children with mitral valve prolapse divided in two groups: first group - without regurgitation (34 children), the second group - with regurgitation (16 children). Results. In healthy children identified were strong correlation links between echocardiographic indices of the subvalvular structures of the mitral valve and the functional parameters of the left ventricle. The diameter of the anterolateral group of papillary muscles directly correlated with the thickness of the interventricular septum, while the diastolic distance between the papillary muscles - with the end diastolic diameter of the left ventricle. It was established that the following factors may contribute to the pathogenesis of mitral valve prolapse: (1) long papillary muscles and the corresponding chords of the valve, (2) a weak (relative to the norm) contractile ability of the papillary muscles, (3) hyperkinesis of the left ventricular apex, and (4) no relationship between the apical and the global ejection fraction. These factors contribute to the fact that the papillary muscles and chords constrain the mitral valve cusps to a lesser extent during systole, which in turn easily bulge into the left atrium under the influence of systolic blood pressure. Apical hyperkinesis contributes to even closer approximation of the subvalvular structures with the cusps. Conclusion. Mitral valve prolapse is attributed to desynchronization of the function of papillary muscles and of the left ventricle; the development of functional mitral regurgitation during mitral valve prolapse is associated with dyssynchrony of the papillary muscles’ activity.

Author(s):  
E. G. Agafonov ◽  
M. A. Popov ◽  
D. I. Zybin ◽  
D. V. Shumakov

Rationale. Secondary, or functional, mitral regurgitation is the most common complication of heart failure. Dysfunction of one or more mitral valve structures occurs in 39–74% of patients thus complicating the course of the disease and significantly worsening the prognosis in patients with left ventricle dilatation. An unfavorable prognosis in patients with the development of mitral regurgitation is conditioned by the progressive changes that form a vicious circle: the continuing volume overload and dilatation of the left ventricle cause its remodeling, leading to further dilatation of the mitral valve annulus. Dysfunctions of the papillary muscles lead to the increased tension of the left ventricle wall and increased mitral regurgitation. Clinically, this process is manifested by the congestive heart failure progression and worsened prognosis of the further course, which in the future may lead to considering the inclusion of this patient group on the waiting list for heart transplantation.Purpose. The purpose of this article is to review the role of surgical management in patients with heart failure complicated by mitral regurgitation.Conclusions. The main principles of the treatment for functional mitral regurgitation include the reverse left ventricular remodeling and mitral valve repair or replacement surgery which lead to an improved quality of life, the transition of patients to a lower functional class, reduced hospital admission rates, and also to a regression or slower progression of the heart failure and to an improved survival.


2021 ◽  
Vol 11 (4) ◽  
pp. 44-51
Author(s):  
A. A. Malov ◽  
R. K. Dzhordzhikiya ◽  
A. I. Abushayev

Introduction. Phenotype variants of left ventricular (LV) remodeling in patients with hypertrophic cardiomyopathy (HCM) are often associated with abnormalities of the mitral valve (MV), myocardiumstructure, contributing to the development of medium and/or subaortic obstruction. Itcauses the detail visualization of morphological obstruction substrates, tissue characteristics.Aim. To evaluate the possibilities of magnetic resonance imaging (MRI) in the diagnosis of various forms of HCM and combined abnormalities.Materials and methods. 75 patients with suspected HCM were examined. For verification, all patients underwentMRI using protocol: short-pulse T1w-TSE/ T2w-TSE (STIR), gradient echo in cine (CINE), T1-weighted post-contrast images (Inversion Recovery IR-MDE). Results. Patients classified into 4 types according to the anatomical principle (Wiggle E.D. et al., 1985). In addition to the most frequent forms affecting the interventricular septum (IVS) — 64 patients, unusual forms covering the apical zones and papillary muscles — 11 patients. The majority of patients were diagnosed with abnormalities of MV, divided into abnormalities of the number and position of papillary muscles, as well as the ratio of chords and muscles. Myocardial crypts were diagnosed in 12 patients, some combined with areas of non-compact myocardium. Post-contrast visualization using the delayed contrast technique allowed differentiating HCM with accumulation diseases, excluding cavity thrombosis, and evaluating the severity of myocardial fibrosis.Conclusions. MRI allows to estimate in details anatomic picture of LV remodeling, to diagnose features of the mitral valve, tissue characteristics that allows to stratify risk of sudden death, classify the HCM phenotype form and to determine the volume of surgical intervention.


Circulation ◽  
2019 ◽  
Vol 140 (11) ◽  
pp. 952-964 ◽  
Author(s):  
Cristina Basso ◽  
Sabino Iliceto ◽  
Gaetano Thiene ◽  
Martina Perazzolo Marra

Despite a 2% to 3% prevalence of echocardiographically defined mitral valve prolapse (MVP) in the general population, the actual burden, risk stratification, and treatment of the so-called arrhythmic MVP are unknown. The clinical profile is characterized by a patient, usually female, with mostly bileaflet myxomatous disease, mid-systolic click, repolarization abnormalities in the inferior leads, and complex ventricular arrhythmias with polymorphic/right bundle branch block morphology, without significant regurgitation. Among the various pathophysiologic mechanisms of electrical instability, left ventricular fibrosis in the papillary muscles and inferobasal wall, mitral annulus disjunction, and systolic curling have been recently described by pathological and cardiac magnetic resonance studies in sudden death victims and patients with arrhythmic MVP. In addition, premature ventricular beats arising from the Purkinje tissue as ventricular fibrillation triggers have been documented by electrophysiologic studies in MVP patients with aborted sudden death. The genesis of malignant ventricular arrhythmias in MVP probably recognizes the combination of the substrate (regional myocardial hypertrophy and fibrosis, Purkinje fibers) and the trigger (mechanical stretch) eliciting premature ventricular beats because of a primary morphofunctional abnormality of the mitral valve annulus. The main clinical challenge is how to identify patients with arrhythmic MVP (which imaging technique and in which patient) and how to treat them to prevent sudden death. Thus, there is a necessity for prospective multicenter studies focusing on the prognostic role of cardiac magnetic resonance and electrophysiologic studies and on the therapeutic efficacy of targeted catheter ablation and mitral valve surgery in reducing the risk of life-threatening arrhythmias, as well as the role of implantable cardioverter defibrillators for primary prevention.


2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
D Rodrigo Carbonero ◽  
U Estandia ◽  
C Perez ◽  
R Voces ◽  
P Perez ◽  
...  

Abstract We report a 43 year-old female with a past TTE echocardiography of rheumatic valve disease performed in her district hospital , ( No clear symptomatology of rheumatic fever in the past). She was transferred to our tertiary hospital for elective cardiac surgery. Preoperative echocardiogram showed a non-dilated left ventricle with preserved contractility, mild-moderate left atrium enlargement with severe mitral regurgitation and basal displacement of papillary muscles and severe tricuspid regurgitation.All of it resembling a hammock mitral valve instead of former echocardiogram described as rheumatic valve disease. Preoperative cardiac study showed severe pulmonary hypertension with increased pulmonary vascular resistances. Preserved biventricular cardiac output and increased proto and telesystolic pressures. During surgery , ifindings were described as a mitral valve with a large papillary muscle inserted in the distal third of the left ventricle with none tendinous cords at the anterior leaflet and without cords in the posterior leaflet with an isolated papillary muscle with cords at A3 and P3 scallops, compatible with hammock mitral valve. A tendinous muscle/fibrous or fibromuscular band connecting the septum to the posterior wall of the left ventricle was described. Moreover over, there was an enlarged tricuspid ring with very short tendinous cords on the septal leaflet, although the leaflet was bigger than usual. Surgery consisted of resection of the mitral valve preserving A3 and P3 scallops with a 29mm Bicarbon Sorin mechanical mitral prosthesis and a 32mm Carpentier tricuspid ring implantation and pulmonary veins ablation combined with occlusion of left atrial appendage. After 112 minutes of cross-clamping time, the patient was weaned from cardiopulmonary bypass. She had important left ventricle dysfunction which improved with dobutamine and AAI pacemaker at 90lpm. Postoperative TEE showed moderate dysfunction of right ventricle, mild left ventricular dysfunction, moderate tricuspid regurgitation and a good functioning of the prosthesis. TTE before discharge showed good function of mitral valve prosthesis, good left ventricle function, mild tricuspid regurgitation, mild-moderate right ventricular enlargement, although less than preoperatively. Conclusion Congenital mitral valulophaty is a rare condition in the adulthood. The estimated prevalence is 0,5%. The hammock mitral valve is a more uncommon pathology which affects the mitral valve and subvalvular apparatus. This anomaly, was first described in 1967 and it is characterised by anomalous papillary muscles directly connected to the anterior mitral valve by a fibrous bridge without chordae tendineae in between them. This fibrous bridge hampers the opening and closure of the mitral valve. Diagnosis requires a high index of suspicion, both ultrasound studies and medical history, to avoid misdiagnosis. Abstract P1720 Figure.


2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Krishan J Patel ◽  
Olujimi A Ajijola ◽  
Michael Fishbein ◽  
Kalyanam Shivkumar

Background: Malignant mitral valve prolapse (MVP) identifies a subset of patients with MVP associated with ventricular arrhythmias (VAs), including sudden cardiac death (SCD). We hypothesized that papillary muscles, which see significant mechanical stress in MVP, are richly innervated with sensory nerves, which induce severe autonomic imbalance on the heart and may trigger malignant VAs. Methods and Results: Longitudinal sections of the anterior and posterior left ventricular papillary muscles, right ventricular outflow tract (RVOT), ventricular septum, and basolateral left ventricular wall (LV) of Yorkshire pigs (n=8) were excised, formalin-fixed, paraffin-embedded, and sectioned. Immuno-staining for protein gene product 9.5 (PGP9.5), a pan-neuronal marker, and calcitonin-gene related peptide (CGRP), a sensory afferent neuron marker, was performed. Areas of immunoreactivity (IR) for CGRP were verified by direct comparison to PGP9.5 IR. The density of CGRP was then compared across anatomical regions. The mean CGRP IR area was 1229.44 ± 116.65 μm 2 /nucleus in papillary muscles, while in the septum, basolateral LV, and RVOT, the CGRP stained areas were 699.36 ± 88.28 μm 2 /nucleus, 681.51 ± 81.90 μm 2 /nucleus, and 381.98 ± 31.14 μm 2 /nucleus, respectively (p<0.001). There was no significant difference between CGRP IR area in the anterior papillary muscle (1091.36 ± 189.82 μm 2 /nucleus) and the posterior papillary muscle (1347.79 ± 140.50 μm 2 /nucleus) (p>0.3). Conclusions: There is a significantly greater amount of afferent innervation in the papillary muscle compared to the septum, basolateral LV, and RVOT. This enrichment of afferent innervation warrants further study to understand how afferent neurotransmission during abnormal mitral valve function may impact ventricular electrophysiology.


2020 ◽  
Vol 75 (5) ◽  
pp. 514-522
Author(s):  
Alexey S. Ryazanov ◽  
Konstantin I. Kapitonov ◽  
Mariya V. Makarovskaya ◽  
Alexey A. Kudryavtsev

Background. Morbidity and mortality in patients with functional mitral regurgitation (FMR) remains high, however, no pharmacological therapy has been proven to be effective.Aimsto study the effect of sacubitrile/valsartan and valsartan on functional mitral regurgitation in chronic heart failure.Methods.This double-blind study randomly assigned sacubitrile/valsartan or valsartan in addition to standard drug therapy for heart failure among 100 patients with heart failure with chronic FMR (secondary to left ventricular (LV) dysfunction). The primary endpoint was a change in the effective area of the regurgitation hole during the 12-month follow-up. Secondary endpoints included changes in the volume of regurgitation, the final systolic volume of the left ventricle, the final diastolic volume of the left ventricle, and the area of incomplete closure of the mitral valves.Results.The decrease in the effective area of the regurgitation hole was significantly more pronounced in the sacubitrile/valsartan group than in the valsartan group (0.070.066against0.030.058sm2; p=0.018)in the treatment efficacy analysis, which included 100patients (100%). The regurgitation volume also significantly decreased in the sacubitrile/valsartan group compared to the valsartan group (mean difference:8.4ml; 95%CI, from 13.2 until 1.9;р=0.21). There were no significant differences between the groups regarding changes in the area ofincomplete closure of the mitral valves and LV volumes, with the exception of the index of the final LV diastolic volume (p=0.07).Conclusion.Among patients with secondary FMR, sacubitril/valsartan reduced MR more than valsartan. Thus, angiotensin receptor inhibitors and neprilysin can be considered for optimal drug treatment of patients with heart failure and FMR.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
T Benito Gonzalez ◽  
X Freixa ◽  
C Godino ◽  
M Taramasso ◽  
R Estevez-Loureiro ◽  
...  

Abstract Background Limited information has been reported regarding the impact of percutaneous mitral valve repair (PMVR) on ventricular arrhythmic (VA) burden. The aim of this study was to address the incidence of VA and appropriate antitachycardia implantable cardiac defibrillator (ICD) therapies before and after PMVR. Methods We retrospectively analyzed all consecutive patients with heart failure with reduce left ventricular ejection fraction, functional mitral regurgitation grade 3+ or 4+ and an active ICD or cardiac resynchronizer who underwent PMVR in any of the eleven recruiting centers. Only patients with complete available device VA monitoring from one-year before to one year after PMVR were included. Baseline clinical and echocardiographic characteristics were collected before PMVR and at 12-months follow-up. Results 93 patients (68.2±10.9 years old, male 88.2%) were enrolled. PMVR was successfully performed in all patients and device success at discharge was 91.4%. At 12-months follow-up, we observed a significant reduction in mitral regurgitation severity, NT-proBNP and prevalence of severe pulmonary hypertension and severe kidney disease. Patients also referred a significant improvement in NYHA functional class and showed a non-significant trend to reserve left ventricular remodeling. After PMVR a significant decrease in the incidence of non-sustained ventricular tachycardia (VT) (5.0–17.8 vs 2.7–13.5, p=0.002), sustained VT or ventricular fibrillation (0.9–2.5 vs 0.5–2.9, p=0.012) and ICD antitachycardia therapies (2.5–12.0 vs 0.9–5.0, p=0.033) were observed. Conclusion PMVR was related to a reduction in arrhythmic burden and ICD therapies in our cohort. Proportion of patients who presented ven Funding Acknowledgement Type of funding source: None


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