Subvalvular Apparatus Research Articles

Establishment and validation of a prediction model for the outcome of rheumatic mitral valve repair surgery based on transthoracic echocardiography

Abstract Background The outcome of mitral valve repair over replacement in degenerative diseases has been recognized, but the patient selection of mitral valve repair in rheumatic diseases are still controversial. At present, there is a lack of comprehensive evaluation methods for rheumatic mitral valve disease, which cannot guide the selection of patients before surgery. Purpose The aim of this study was to establish a comprehensive evaluation method and innovative indicators for rheumatic mitral valve disease using transthoracic echocardiography, and to establish a model for predicting the outcome of rheumatic mitral valve repair. Methods This prospective, multicenter, observational cohort study included 167 patients who underwent rheumatic mitral valve surgery in 4 centers from 2022 to 2023. Each enrolled patient underwent a comprehensive transthoracic echocardiography evaluation and measured 94 ultrasound indicators, mainly covering leaflets, annulus, subvalvular apparatus, and atrial and ventricular function. The main endpoint event was the failure of mitral valve repair (including switching to replacement after repair, and moderate to severe stenosis or regurgitation during follow-up after repair). Patients were randomly assigned to the modeling and validation groups at a ratio of 7:3. In the modeling group, LASSO regression was used for variable selection, and logistic regression was used for modeling. A nomogram was drawn and a webpage rating calculator was created. In the validation group, model comparisons were conducted using the C-statistic and Net Reclassification Index (NRI). Results 112 patients (67.1%) underwent mitral valve repair with satisfactory results, 47 patients (28.1%) ultimately underwent mitral valve replacement, and 8 patients (4.8%) found moderate to severe mitral stenosis or regurgitation during follow-up after repair. Three indicators, including mitral valve orifice area, leaflet calcification score, and anterior leaflet-annulus angle, were selected through LASSO regression. No collinearity was found between the three indicators, and they were ultimately included in the logistic regression model. The C statistics in the modeling group and validation group were 0.846 and 0.958, respectively, indicating that the constructed model has satisfactory predictive ability. Compared to the Wilkins score, the proportion of correctly classified items increased by 19.8%, significantly better than the Wilkins score. Finally, a nomogram was drawn based on the model, and a web rating calculator was created to guide clinical decision-making. Conclusion This study explored a comprehensive evaluation method and innovative indicators for rheumatic mitral valve disease by transthoracic echocardiography, established and validated a model for predicting the outcome of repair surgery, and had certain guiding significance for doctors to choose suitable patients for rheumatic mitral valve repair.Validation of the predictive modelNomogram

Anatomy of the Right and Left Ventricular Subvalvular Apparatus of the Horse (Equus caballus).

Due to the growing interest among veterinarians and the increasing market demands, the development of equine cardiology is necessary. Currently, veterinary medicine for companion animals needs to catch up to human medicine-equine medicine included. A common condition in older horses is aortic valve regurgitation resulting from fibrosis, while its more severe form occurs in younger horses or develops due to a bacterial infection. Mitral valve regurgitation, especially dangerous due to the possibility of sudden death, has a better prognosis if the horse has valve prolapse. Tricuspid valve regurgitation usually does not pose a clinical problem, although its severe cases may lead to heart failure. Some pathologies can be treated surgically, which requires excellent knowledge of anatomy. The object of this study consisted of twenty domestic horse hearts. The focus was on the normal and comparative anatomy of the left and right subvalvular apparatus. The number of muscular bellies of the papillary muscles and the type of connection of the muscles were analysed. Moreover, the height of muscle originating from the ventricle wall was determined, the morphological regularity of the papillary muscle was assessed, and the chordae tendineae originating from the papillary muscles were examined. The conducted research allowed for comparing domestic horses with different species through other studies, the authors of which described this particular aspect. Interspecies similarities which may be correlated with the evolutionary relatedness, as well as differences that could reflect adaptation to different lifestyles, environmental conditions, or metabolic requirements of the animals, have been found. This study expands the knowledge of animals' normal and comparative anatomy, and contributes to the development of veterinary surgery, internal medicine, and biology.

A rare presentation of an accessory mitral valve chordae.

The mitral subvalvular apparatus can exhibit complex and unique anatomical variations. Accessory mitral valve chordae (AMVC) typically present as additional thin strands in the left ventricle. Their appearance in the atrium is rare. In the clinical case described, the AMVC was an incidental and intriguing finding during a routine transthoracic echocardiography.

Artificial Chordae Implantation vs Posterior Leaflet Preservation: A Comparison of Midterm Results After Mitral Valve Replacement.

Various techniques have been proposed for the preservation of the subvalvular apparatus (SVA) in mitral valve replacement. This study aimed to compare the midterm results of posterior leaflet preservation with the results of selective preservation of the SVA involving artificial chordae implantation in terms of left ventricular performance in patients undergoing mitral valve replacement. In total, 127 patients were included in this study. Patients were allocated to 1 of 2 groups according to the techniques used to preserve the SVA. Patients in group 1 underwent posterior leaflet preservation: The anterior leaflet was completely resected, and the posterior leaflet was preserved. In group 2, which comprised patients with severe leaflet extension and subvalvular fusion, the mitral valve was excised completely and substituted with artificial chordae. All relevant preoperative, intraoperative, and postoperative data were recorded. Mean (SD) ages in groups 1 and 2 were 63.1 (9.65) and 57.1 (12.3) years, respectively (P = .003). Mean (SD) follow-up time was 59.97 (23.63) months (range, 6-99 months). Left ventricular end-diastolic diameter decreased significantly after artificial chordae implantation (P < .001), while the decrease after posterior leaflet preservation was not statistically significant (P = .20). In both groups, there were statistically significant reductions (P < .001) in left ventricular end-systolic diameter and left atrium diameter in the postoperative period compared with respective preoperative levels. During follow-up, left ventricular ejection fraction was found to have increased beyond the preoperative levels in both groups, but the differences were not statistically significant (P > .05). Results of echocardiographic observations regarding the preservation of the SVA via artificial chordae implantation for mitral valve disease in this sample were satisfactory. Findings suggest that artificial chordae implantation should be considered when posterior leaflet preservation is not suitable.

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.

SEVERE MITRAL INSUFFICIENCY FROM RHEUMATIC DISEASE: A CASE REPORT

Abstract Acute rheumatic fever continues to be a major health problem in many parts of thw world. It’s more common in low–income or developing parts of the world. Antibiotics for bacterial infections may not be available in these areas. In developed countries, cardiac involvement is quite rare. Although traditionally considered to be a disease associated with poverty, rheumatic fever continues to persist even among the middle–class population in developed countries. Children and teenagers with intreated strep infections are the most likely to get rheumatic fever. Signs of heart damage can develop years after the infection. Rheumatic heart disease is the result of valvular damage caused by an abnormal immune response to Streptococcus pyogenes infection. After multiple episodes of rheumatic fever, progressive fibrosis of the heart valves can occur: mitral regurgitation is the most common valvular lesion. We report the case of a 13–year–old, Italian, middle–class girl with rheumatic mitral valve involvement. A 13–years–old comes to the clinic for onset of worsening dyspnea ad easy fatigability. History turns out to be negative for cardiovascular disease and history of recent infections. Echocardiographic examination showed a dilated left ventricle (VTD 148ml, 98 m/mq) with preserved chinese. Severe dilatation of the left atrium with atrio–aortic ratio 2.3 and atrial volume 91 ml/mq. The mitral valve presented a myxomatous, thickened leaflets, predominantly the posterior which appeared retracted and hypomobile with thickening of the subvalvular apparatus with coaptation deficit along the entire coaptation rhyme realizing severe degree insufficiency (CV 7mm, ERO 0.8 cm2, CO 39 l/min). A small cleft at the level of A1, main lesion jet (A1–P3–P2) was also visible. The Echocardiographic appearance suggested outcomes from rheumatic disease so antistreptolysin titer and anti–DNase B antibodies were assayed with high levels found. Penicillin prophylaxis was therefore initiated. For the continuation of the therapeutic course, the case was discussed collegially and a valve replacement rather tan repair was advocated because the valvular and subvalvular apparatus were far too damaged.

In vivo mitral valve repair for the transplanted donor heart in orthotopic heart transplantation

A 53-year-old woman with the dilated phase of hypertrophic cardiomyopathy underwent orthotopic heart transplantation. The donor heart was evaluated as normal preoperatively without mitral regurgitation or the left atrium dilation, transplanted using the modified bicaval technique. Although the heart beat satisfactorily after aortic declamping, massive mitral regurgitation was observed without any prolapse or annular dilation. Because of the difficulty in weaning from cardiopulmonary bypass, a second aortic cross-clamp was applied, and we detached the inferior vena cava and the right side of the left atrial anastomosis to approach the mitral valve, obtaining a satisfactory exposure. No abnormalities were observed in the mitral valve leaflets, annulus or subvalvular apparatus. Subsequent in vivo mitral annuloplasty using prosthetic full ring successfully controlled the regurgitation, and the patient was easily weaned from cardiopulmonary bypass. She discharged to home with good mitral valve and cardiac functions. And the patient has been doing well without any recurrence of MR or heart failure for over a year after surgery.

Cardiac implantable electronic device-induced tricuspid regurgitation: Implications and management.

Tricuspid regurgitation (TR) secondary to cardiac implantable electronic devices (CIEDs) has been well documented and is associated with worse cardiovascular outcomes. A variety of mechanisms have been proposed including lead-induced mechanical disruption of the tricuspid valvular or subvalvular apparatus and pacing-induced electrical dyssynchrony. Patient characteristics such as age, sex, baseline atrial fibrillation, and pre-existing TR have not been consistent predictors of CIED-induced TR. While two-dimensional echocardiography is helpful in assessing the severity of TR, three-dimensional echocardiography has significantly improved accuracy in identifying the etiology of TR and whether lead position contributes to TR. Three-dimensional echocardiography may therefore play a future role in optimizing lead positioning during implant to reduce the risk of CIED-induced TR. Optimal lead management strategies in addition to percutaneous interventions and surgery in alleviating TR are very important.

Impact of the Tricuspid Valve Detachment Technique on Hard-to-Expose Ventricular Septal Defect Closure

Ventricular septal defect (VSD) closure is a common procedure in congenital heart surgery. The exposure of VSDs can be challenging, especially in cases involving the tricuspid septal or anterior leaflets, chordae, or subvalvular apparatus. Although tricuspid valve detachment has been suggested to improve surgical visibility, its long-term effects remain unclear. Herein, we investigated the outcomes of VSD closure with or without tricuspid valve detachment and assessed the impact of this technique on postoperative tricuspid valve function and atrioventricular conduction. In total, 175 patients who underwent isolated VSD closure through the right atrium were retrospectively enrolled and divided into 2 groups: the tricuspid valve detachment group (n = 17, 9.7%) and the nontricuspid valve detachment group (n = 158, 90.3%). Patient characteristics were comparable between the two groups, and medical records and echocardiography reports were reviewed for each patient. The primary outcomes were mortality and reoperation, whereas the secondary outcomes included residual VSD, tricuspid valve regurgitation, advanced atrioventricular block, and aortic valve regurgitation. Clinical variables were compared between the two groups. Overall, tricuspid valve detachment did not increase perioperative complications or affect long-term tricuspid valve function. There were no cases of mortality or reoperation in either group. Although the tricuspid valve detachment group had longer bypass and cross-clamp times, this did not significantly affect ventilation or intensive care unit stay duration. Follow-up echocardiography revealed no significant intergroup differences in tricuspid regurgitation, residual shunt, or aortic valve regurgitation. In conclusion, tricuspid valve detachment is a safe and reliable technique for the complete closure of hard-to-expose VSDs without compromising tricuspid valve function. Moreover, it does not increase the risk of adverse events, and its outcomes remain favorable during short- and long-term follow-ups.

CASE-FA-06 - Cardiac Magnetic Resonance (CMR) in the Evaluation of Mitral Subvalvular Apparatus on a Patient with Dilated Cardiomyopathy

CASE-FA-06 - Cardiac Magnetic Resonance (CMR) in the Evaluation of Mitral Subvalvular Apparatus on a Patient with Dilated Cardiomyopathy

Diagnostic value of papillary muscle hypertrophy and mitral valve thickness to discriminate cardiac amyloidosis and Fabry disease

BackgroundCardiac amyloidosis (CA) and Fabry disease (FD) cause myocardial damage but may also affect the valvular and subvalvular apparatus. We aimed to evaluate the diagnostic accuracy of new echocardiographic indices including mitral valve thickness and papillary muscle (PM) hypertrophy to differentiate CA and FD. MethodsIn patients with confirmed CA and FD, a detailed assessment of valvular function, mitral valve leaflet thickness and PM area as well as PM left ventricular area ratio (PM/LV-ratio) was performed in offline analyses. Receiver operating characteristic curve analyses were conducted to determine the diagnostic accuracy of mitral valve thickness, PM hypertrophy, and PM/LV-ratio to distinguish CA from FD. ResultsWe retrospectively analyzed a cohort of 129 patients (FD n = 49, CA n = 80). CA patients showed significantly more thickened mitral valve leaflets (4.1 ± 1.3 mm vs. 2.9 ± 1.1 mm, p < 0.001) and a higher PM area [4.0 (3.1–4.6) mm2 vs. 2.8 (2.1–4.6) mm2, p = 0.009] with a comparable PM/LV-ratio in both groups. Mitral valve thickness showed the highest diagnostic accuracy to discriminate CA [AUC 0.77 (95% CI 0.67–0.87)]. The prevalence of aortic, tricuspid, and pulmonary valve regurgitation was significantly higher in CA (aortic regurgitation ≥ II° 13% vs. 4%, tricuspid regurgitation≥ II° 19% vs. 8%, p < 0.001). ConclusionOur results suggest that the assessment of mitral valve thickness may be a new useful echocardiographic parameter to differentiate CA and FD, whereas papillary muscle hypertrophy and PM/LV-ratio showed a limited diagnostic performance to discriminate CA.German clinical trials registry: DRKS00027403.

Abstract 14934: Libman-Sacks Endocarditis and Sjogren’s Syndrome: Are They Associated?

Introduction: Libman-Sacks endocarditis (LSE) in patients with systemic lupus erythematosus (lupus) is frequently complicated with stroke or TIA, acute or chronic progressive valve dysfunction, need for high-risk valve surgery, and increased morbidity and mortality. Sjogren’s syndrome characterized by dry eyes and mouth for &gt;3 months and positive anti-Ro/SSA or SSB antibodies is common in lupus patients, but its association with LSE is unknown Aim: To determine if Sjogren’s syndrome is associated and predictive of LSE. Methods: 76 lupus patients (71 women, 36 ± 12 years of age) and 26 age-and-sex frequency (3:1 ratio) matched controls (22 women, 34 ± 11 years of age) underwent TEE and assessment of demographics, atherogenic risk factors, and parameters of inflammation and thrombogenesis. Patients were also assessed for lupus duration, activity, injury, autoantibodies, and therapy. Libman-Sacks vegetations by TEE were defined as localized, protruding, and sessile echodensities &gt;3 mm in diameter with well-defined borders as part of valve leaflets, annulus, or subvalvular apparatus. All studies were coded, de-identified, and interpreted by observers blinded to participants’ clinical data. Univariate and multivariate regression analyses were used to identify predictors of LSE. Results: 39 (51%) lupus patients and 2 (8%) controls had vegetations (p&lt;0.001). Also, 39 (51%) patients had Sjogren’s syndrome and 28 (72%) of them had vegetations (p&lt;0.001). As shown in Table 1 , age, Sjogren’s syndrome, current smoking, β-2 glycoprotein antibodies, lupus duration, acute or recent stroke/TIA, past stroke, lupus activity and damage scores, and anti-thrombotic therapy were univariate predictors of LSE (all p≤ 0.05). However, Sjogrens’ syndrome, acute or recent stroke or TIA, and duration of lupus were the only multivariate predictors of LSE (all p≤0.02). Conclusions: Sjogren’s syndrome is an independent predictor of Libman-Sacks endocarditis.

Abstract 18126: A Rare Case of a Left Ventricular Papillary Fibroelastoma With an Initial Presentation of Unilateral Vision Loss

A 59-year-old female with hypertension presented with acute onset of decreased vision in the right eye. She reported waking up 3 days prior to admission with sudden onset of shadow in the right eye appearing like a falling curtain which eventually progressed to total visual loss. She also complained of headaches and palpitations. The patient denied pain, nausea, vomiting, photophobia, changes in speech, aphasia, facial weakness, arm or leg weakness or numbness. She states that this is her first experience of vision loss. At the time of admission, she was hypertensive to 170/100s and started on amlodipine 5mg and losartan 25mg. Neurology and ophthalmology were consulted for concerns of stroke and new vision loss. She was started on heparin drip, aspirin 81mg, atorvastatin 80mg, and methylprednisolone 1g. Ocular examination revealed right brachial retinal artery occlusion. MRI brain showed chronic microvascular changes, but no acute intracranial hemorrhage or infarction. CT angiogram of the neck showed mild soft plaque in right carotid bifurcation. Transthoracic echocardiogram revealed a 1.6cm x 1.6cm left ventricular mobile mass which appeared to be attached to the posteromedial papillary muscle and left ventricle ejection fraction of 60%. The patient underwent open heart surgery for removal of the mass. The mass was confirmed to be a papillary fibroelastoma attached to the left ventricular trabeculum. The mitral valve and subvalvular apparatus were not involved. New onset of stroke or acute vision loss is generally a result of thromboembolism. Most times it can be caused by a clot formed in a patient with atrial fibrillation. In other cases, it can be due to a ruptured cholesterol plaque. However, primary cardiac tumors are rare, especially ones on the papillary muscle. We presented a rare case of papillary fibroelastoma that possibly embolized causing acute unilateral vison loss. This case reinforces the importance of cardiac imaging in new stroke or acute vision loss.

Abstract 18212: The Fat Embolism Enigma: Unveiling the Intricate Complications of Breast Reconstructive Surgery

Background: Fat embolism can occur after plastic surgery, especially when injecting fat into subcutaneous tissue. It can be asymptomatic or can have hypoxia, mental status changes, and petechiae rash. Diagnosis is challenging but the workup includes imaging to exclude other differentials including pulmonary thromboembolism. Echocardiography assists in identifying fat emboli. Case Presentation: A middle-aged female with no prior cardiac history was undergoing right-sided breast reconstructive surgery with liposuction from the abdomen and fat grafting. Intraoperatively, the patient became hypoxic and hypotensive. The patient was started on vasopressors. A CT-Angiogram Chest revealed multiple bilateral pulmonary emboli, with some emboli having negative Hounsfield units (HU). Anticoagulation was started. Fat emboli could not be excluded. The patient was ultimately transitioned to venoarterial extracorporeal membrane oxygenation. Transthoracic echocardiogram showed right ventricular (RV) hypokinesis with preserved apical function and multiple, mobile, irregular masses in the RV. Figure 1 With the patient’s history, this was concerning for fat emboli. A transesophageal echocardiogram (TEE) showed multiple (4 visualized) masses seen in the RV, caught into the subvalvular tricuspid apparatus on the chordae and the RV trabeculation. (Largest mass: 1 cm in diameter). Figure 2 A bilateral lower extremity venous duplex was negative. The patient was diagnosed with obstructive shock secondary to fat embolism. She was eventually weaned off of mechanical support and discharged in stable condition. Discussion: Autologous fat grafting (AFG) has gained popularity in reconstructive and aesthetic surgery. It is important to remain vigilant about fat embolism as a complication that presents as sudden hypoxia and obstructive shock in the appropriate setting. DVT should be ruled out. Echocardiography can assist in diagnosis. Treatment is supportive.

Abstract 18273: Mitral Annular Calcification is Associated With Higher Operative Risks and Worse Survival in Hypertrophic Cardiomyopathy

Background: Mitral annular calcification (MAC) is common in hypertrophic cardiomyopathy (HCM), usually accompanied by mitral leaflet calcification, subvalvular apparatus calcification, and mitral valve dysfunction. However, the impact of MAC on surgical strategy and clinical outcomes in HCM is not fully understood. Methods: This cohort enrolled 1035 consecutively recruited patients diagnosed with HCM between January 2016 and December 2021. All patients received a computed tomographic scan prior to surgery. Results: Of the 1035 patients, 112 (10.8%) had MAC, including 39 patients with moderate or severe MAC (calcification area greater than one-third of the annulus). Patients with MAC were significantly older (59.6±8.2 years vs. 47.5±12.3 years, p&lt;0.001) and more likely to be female (61.8% vs. 35.4%, p&lt;0.001). Echocardiography showed a higher proportion of mitral leaflet thickening (17.9% vs. 6.0%, p&lt;0.001) in patients with MAC. Moreover, patients with MAC had a higher rate of annular reconstruction (1.79% vs 0.11%, p=0.002), plastic ring implantation (5.36% vs 1.84%, p=0.017), chordae release (12.50% vs 5.09%, p=0.002), artificial neochordoplasty (2.68% vs 0.54%, p=0.015), and fibrous membrane removal (8.93% vs 4.12%, p=0.022), as well as longer ventilation time [19 hours, interquartile range (IQR) 17.0-26.0 vs. 18 hours, IQR 14.0-20.5, p&lt;0.001], intensive care unit stay [61 hours, IQR 36.5-96.0 hours vs. 48 hours IQR 24.0-72.0 hours, p&lt;0.001] and postoperative hospital stay [8days, IQR 7-11 days vs. 7 days, IQR 6-8 days, p&lt;0.001]. During a median follow-up time of 26.2 months (IQR, 17.0 to 39.5 months), 5 death and 158 major adverse cardiovascular events (MACE) were observed. Kaplan-Meier survival curves showed that patients with MAC had a higher cumulative rate of all-cause mortality (p=0.026) and MACE (p=0.003) compared to their counterparts. On multivariable Cox regression analysis, moderate or severe MAC was an independent risk factor for MACE (Hazard ratio =2.38, 95% confidence interval: 1.31-4.32). Conclusions: The prevalence of MAC was 10.8% in this study. The presence of MAC was associated with a higher rate of concomitant operations, longer hospital stays, and worse survival.

The role of echocardiography in management of patients with hypertrophic cardiomyopathy (review)

The presented contains the discussion about the role of echocardiography in management of patients with hypertrophic cardiomyopathy (HCM). The article provides general information about the role of echocardiography in the diagnosis of the disease, clarification of the specific etiology of hypertrophy and differential diagnosis with secondary hypertrophy and phenocopies of HCMP. The features of right and left ventricular (LV) hypertrophy, determination of its predominant localization, phenotype, and conventionally used parameters for assessing myocardial hypertrophy, including the maximum LV wall thickness, LV myocardial mass and LV myocardial mass index, are discussed in detail. Knowledge of phenotypic variants helps to diagnose HCMP, to differentiated approach the management of patients and to choose the optimal treatment strategy. Special attention is paid to the assessment of the structure and function of the mitral valve (MV), the subvalvular apparatus and the phenomenon of systolic anterior motion of the MV responsible for the development of obstruction of the LV outflow tract. The previously existing opinion that cardiac abnormality in HCMP is limited only by hypertrophy of ventricular myocardium has recently undergone changes. Approximately 60% of patients with HCMP have at least one MV anomaly as a direct consequence of genetic mutations. The most common abnormalities that can be detected with echocardiography include elongation of the valvular leaflets and chords, prolapse of the valvular leaflets, hypertrophy, disposition and change in the number of papillary muscles. The importance and significance of assessing LV systolic and diastolic functions using echocardiography is emphasized. The role of transesophageal echocardiography in visualization of hypertrophy features of the MV structure and in the perioperative period during surgical correction of hypertrophied septum and valvular defects is also discussed.

Obstructive hypertrophic cardiomyopathy: a review of new therapies.

Hypertrophic cardiomyopathy (HCM) is a phenotypically heterogeneous disease with a genetic basis and variable penetrance. The hallmarks of HCM include dynamic left ventricular outflow tract obstruction, typically caused by asymmetric septal hypertrophy. However, abnormal papillary muscle placement, abnormal mitral valve and subvalvular apparatusand apical hypertrophic forms have also been described. Typical medical treatment has been stagnant for decades, although there have been significant advances in surgical treatment of patients with obstructive HCM. Herein, we describe a new class of drugs targeting the specific pathophysiology of HCM.

Insights of tricuspid regurgitation mechanisms in patients with right ventricular apical pacing by three-dimensional echocardiography.

Device lead-induced tricuspid regurgitation (LITR) mechanisms are well-defined by 3D transthoracic echocardiography (3D-TTE). There is a lack of data on the Latin-American population. The objective of this study was to describe the prevalence of several mechanisms and insights in patients with permanent right ventricular (RV) implanted devices by 3D-TTE examination. We performed a cross-sectional analysis of 101 patients with permanent cardiac devices such as pacemakers or defibrillators. 3D-TTE was obtained on all patients in RV-focused apical views to perform a complete tricuspid valve (TV) evaluation: leaflets, subvalvular apparatus, precise lead location, and functional assessment to evaluate possible mechanisms of tricuspid regurgitation (TR). In a total of 101 patients, the leads did not interfere with TV function in 53 p. (59%), while LITR was observed in 38 (41%) patients. Adherent, impinging, entangled, and mixed lead-induced mechanisms were observed. Time in years since device implantation was significantly higher in patients with LITR. LITR was present in a high proportion of our population. LITR is the result of damage to the TV as well as its subvalvular apparatus due to the fibrotic and inflammatory response over time when leads are situated in unfavorable locations.

C36 NON–CYCLIC INTERMITTENT PROSTHETIC MITRAL VALVE DYSFUNCTION: A CASE REPORT OF A DIFFICULT DIAGNOSIS CONFIRMED WITH MULTIMODALITY IMAGING

Abstract A 59–year–old man,obese,with history of hypertension, 3 years ago underwent mitral valve (MV) replacement with a mechanical prothesis(Sorin Bicarbon 31) and preservation of the native subvalvular apparatus for severe mitral regurgitation due to anterior leaflet flail. Pre–discharge transthoracic echocardiography (TTE) showed normal prothesis function (mean pressure gradient (PG) 3,2mmHg), no valvular leaks and a normal ejection fraction (EF). Lately, the patient was admitted twice to emergency department for signs of heart failure, solved with increasing dose of oral diuretics. In both cases a TTE showed a normal EF, a trans–prosthetic mean PG of 6,5mmHg and no valvular impairment/leaks. Since the suboptimal TTE acoustic windows, a transesophageal echocardiography (TEE) was recommended. TEE showed a normal motion of both MV discs and no pannus/thrombus or leaks with the use of a 2–beat acquisition protocol. However, with longer observation a pattern of non–cyclic intermittent valve dysfunction was noted: whereas some cardiac cycles showed normal discs’ motion, other cycles demonstrated an emi–disc opening delay or blockage during diastole with significant prolongation of transmitral pressure half–time and higher transvalvular gradient, suggestive of flow impairment. A cine fluoroscopy and a CT assessment were also performed, showing the visible intermittent pattern of valve dysfunction without radiological signs of thrombosis or pannus. At this point, the interference of the MV apparatus with the emidisc was considered the most probable mechanism of dysfunction. A Heart Team decision toward reintervention was taken since the risk of a sudden worsening of the mechanical valve function, with potentially lethal consequences, was considered high. The surgeon at visual inspection confirmed the interference of the subvalvular apparatus with the posterior emidisc motion. The chronic shear stress generated on the mitral remnant likely developed a progressive fibrotic response that determined the thickening of the tissue and the periodical entrapment of the disc. MV prothesis was replaced with resection of the subvalvular apparatus. At dismissal,TTE evaluation showed normal valvular function confirmed at 6 months follow–up. Intermittent prosthetic MV dysfunction is a rare but potentially serious complication of MV replacement with subvalvular apparatus preservation. TEE, cine–fluoroscopy and CT may be useful as complementary tools to detect this rare complication.

P270 THE IMPORTANCE OF INTEGRATED IMAGING IN THE DIFFICULT DIFFERENTIAL DIAGNOSIS OF A LEFT INTRACARDIAC MASS IN YOUNG ADULT

Abstract The patient is a 34–year–old man who comes to the emergency room with mild hemoptysis, asthenia, low–grade fever, night sweats and weight loss. Cardiac auscultation reveals a diastolic murmur at the cardiac apex. Transthoracic and transesophageal echocardiograms are performed and show an isoechoic thickening encompassing the posterior leaflet, cranially involving the atrial septum and the lateral wall up to the inlet of the left atrial appendage and inferiorly involveing the subvalvular apparatus with diffuse thickening and chordal fusion. Functionally it determines a moderate mitral stenosis with an average gradient of 10 mmHg and a valve area of ​​1.1 cm2 and a mild–moderate regurgitation with an anteriorly directed eccentric jet. At this point we needed to make the differential diagnosis considering as possible etiologies infective endocardic vegetation, thrombosis, primary and secondary neoplasms, aseptic vegetation and inflammatory or rheumatic valvulitis. We therefore begin our diagnostic work–up by performing a scintigraphy with labeled leukocytes, which does not show the presence of hyperuptake areas referable to infective endocarditis, and a PET scan which shows, in addition to the increased uptake at the cardiac level, an area of ​​greater concentration of the metabolic tracer in the gastric area (between the body and the fundus). Given the confirmation of metabolically active tissue, the patient performed cardiac magnetic resonance with contrast medium which confirmed the presence of pathological tissue with inhomogeneous late post–contrast enhancement. After collegial discussion, due to the high risk of biopsy of the mitral lesion, which was poorly separable from the cardiac structures, given the other localization of the disease at the gastric level, it was decided to perform an EGDS with relief of an ulcerated lesion on the gastric fundus which is subjected to biopsy and histological typing. We then arrive at the diagnosis of “undifferentiated pleomorphic sarcoma”. Sarcoma is the most frequent histological type of primary malignant cardiac tumors. The clinic is characterized by constitutional symptoms, obstruction of the valve inflow or outflow tract, thromboembolism, and arrhythmias. It has a poor prognosis: 6–12 months from diagnosis. In conclusion, we reiterate the importance of integrated imaging to arrive at the final diagnosis, each method with a specific objective.