Dynamic Obstruction Research Articles

Dynamic Fluoroscopic Myelography in the Evaluation of Spinal Dorsal Arachnoid Web

Dorsal arachnoid web is a challenging condition to diagnose on MR imaging. MR imaging flow studies have shown altered CSF flow dynamics near the web. We describe the findings of an arachnoid web with dynamic fluoroscopic myelography in a 77-year-old man. Dynamic myelography revealed functional CSF flow obstruction and focal dorsal thecal sac enlargement with a dynamic change in size at the T6 level.

Comparative study of myocardial function in cases of feline hypertrophic cardiomyopathy with and without dynamic left-ventricular outflow-tract obstruction.

In recent years, hypertrophic cardiomyopathy (HCM) in cats has become much more common in clinical practice due to improvements in diagnostic techniques and equipment performance. One phenotype is obstructive HCM with left ventricular (LV) outflow tract obstruction (DLVOTO). It has been reported that the presence or absence of DLVOTO does not affect long-term prognosis in cats with HCM. In this study, we evaluated and compared myocardial function in HCM-affected cats with and without DLVOTO using the two-dimensional speckle-tracking echocardiography. LV longitudinal strain of the endocardial, epicardial, and whole layer and LV circumferential strain of the epicardium were significantly decreased in all HCM-affected cats compared to healthy cats. However, these values were not significantly different between those with and without DLVOTO. In contrast, the endocardial and whole layers of LV circumferential strain were only significantly decreased in HCM-affected cats with DLVOTO compared to healthy cats. This could be attributed to the fact that the LV pressure load associated with DLVOTO affected the endocardial myocardium more in the LV endocardial layer, and that lower values of LV endocardial strain lowered the values of LV strain in the whole layer. In conclusion, our results suggest that LV myocardial function may have been more compromised in the HCM-affected cats with DLVOTO.

The role of cleft and/or indentation in mitral regurgitation etiology detected by three-dimensional echocardiography in patients with hypertrophic cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: None. Aim The pathophysiology of hypertrophic cardiomyopathy (HCM) consists of dynamic left ventricular outflow tract obstruction, myocardial ischemia, diastolic dysfunction and mitral regurgitation. Mitral regurgitation may be secondary to left ventricular outflow tract obstruction (LVOTO) or related to primary mitral valve pathologies. Three-dimensional (3D) echocardiography has revolutionized imaging of the mitral valve by allowing real-time direct visualization of the mitral valve leaflets in HCM. 3D echocardiography has been using increasingly to evaluate mitral valve clefts and indentations. The aim of this study is to define the frequency of clefts and indentations, and to determine their contribution to mitral regurgitation in patients who are diagnosed HCM and moderate or severe mitral regurgitation by imaging with 3D echocardiography. Methodology A total of 74 patients who were diagnosed with HCM in accordance with current guidelines and moderate or severe mitral regurgitation who underwent 3D transesophageal echocardiography (TEE) between Aug 2018 and May 2022 were retrospectively enrolled. In the control group, 200 patients with moderate or severe mitral regurgitation without diagnosis of HCM were selected. Two groups were compared with each other by demographical, echocardiographical features and cardiac magnetic resonance images. Results Our final patient population was a total of 50 patients after exclusion criteria. The number of 24 (48%) was female and the number of 26 (52%) was male. There was 89 female patient (44,5%) and 111 male patient (55,5%) in the control group. Patients who are diagnosed HCM were younger compared with the control group (mean age 54,5 ±14 year for HCM patients versus 61±14 year for control patients). Cleft/indentation was present in 14 (28%) HCM patients versus 31 (15,6%) in control patients. It was determined that cleft/indentation was more prevelant in HCM patients (p = 0,041). When we evaluate the direction of mitral regurgitation jet with the presence of celft/indentation, there was a significant association between anteriorly directed mitral regürgitation jet and the presence of cleft (p = 0,003). Conclusion In this study, the frequency of cleft/indentations in HCM patients was 28%, it means that cleft/indentation is more often in HCM patients according to the patients who have moderate or severe mitral regurgitation without HCM. When the cleft exists, it affects on the direction of mitral regurgitation and leads to anteriorly directed jet. On the other hand, the indentations have no effect on the direction of mitral regurgitation jet. As a result, 3D mitral valve modeling can be helpful to make a differential diagnosis in HCM patients with anteriorly directed mitral regurgitation jet. Morover, there is no significant efficacy in management of mitral regurgitation by using 3D mitral valve modeling to describe indentations solely.

C62 CHALLENGING DIAGNOSIS OF A TRIPLE CARDIAC PATHOLOGY: TRANSTHYRETIN AMYLOIDOSIS WITH ASPECTS OF HYPERTROPHIC OBSTRUCTIVE CARDIOMYOPATHY AND ANOMALOUS CORONARY ARTERY

Abstract A 70 years–old man with a history of systemic hypertension and surgically treated bilateral carpal tunnel was referred for dyspnea on exertion for few months. At physical examination a systolic heart murmur exacerbated by Valsalva maneuver was appreciated; no signs of heart failure. EKG with low–voltage QRS is shown in Fig.1A. Blood tests showed elevated NT–proBNP (1434 pg/ml). Transthoracic echo (ETT) revealed hyperdynamic left ventricle (LV) with severe asymmetric hypertrophy (interventricular septum 23 mm, posterior wall 17 mm), ‘granular sparkling’ appearance of myocardium, grade 2 diastolic dysfunction and ‘apical sparing’ pattern at global longitudinal strain (GLS, Fig.1B). Moreover, elongated mitral leaflets, anomalies of mitral sub–valvular apparatus with apically displaced papillary muscles and systolic anterior motion of the mitral valve (SAM) with dynamic outflow tract obstruction (20 mmHg at rest and 90–100 mmHg with Valsalva maneuver) were seen (Fig. 2A–B–C). For ETT suspicion of a coronary artery anomaly (Fig.3A), the patient underwent coronary CT angiography that confirmed a separate origin of left anterior descending artery (LAD) from right coronary sinus with a long mid–proximal intramyocardial bridge (Fig.3B–C). As a part of evaluation of the hypertrophic phenotype, a 99mTC–HDP bone scintigraphy was performed with high–grade of cardiac uptake (Perugini Score 2, Fig.1C). Screening for monoclonal gammopathy and genetic testing for hereditary amyloidosis resulted negative. Cardiac MRI revealed late gadolinium enhancement (LGE) in midwall septum, diffuse endocardial LGE in the LV basal inferior and posterolateral walls (Fig.1D), elevated T1 mapping and ECV (40–42%) and confirmed the asymmetric hypertrophy with apically displaced papillary muscles (Fig.2D) and SAM. These clinical, EKG and imaging features led to a non–invasive diagnosis of wild–type transthyretin cardiac amyloidosis (ATTRwt) with aspects of hypertrophic obstructive cardiomyopathy (HOCM). The patient started a disease–modifying therapy with Tafamidis and, cautiously, Metoprolol tartrate, with good tolerance and relevant reduction of LVOT obstruction at follow–up. Genetic testing for HCM was also performed. In conclusion, in rare cases hypertrophic phenotype may be challenging, showing features overlap between ATTR and HOCM. Multimodality evaluation is crucial for a correct diagnosis, thus identifying the most effective target–therapy for the underlying hypertrophic phenotype.

P29 LVOTO IN HCM: HYBRID TREATMENT MAY STILL NOT SOLVE CHALLENGING CASES

Abstract MA, a 28 years old male with a diagnosis of OHCM since 2008, came to our attention for effort dyspnea (NYHA II) and fatigue limiting his greengrocer activity. Decompensated T1DM (HbA1C 12%), HTN, obesity (BMI 37). In 2017 he implanted a bicameral ICD in primary prevention, later extracted for sepsis and replaced with S–ICD. In the last 2 years he had 3–4 episodes of FAP, the latter causing an AHF requiring hospitalization in ICU. CV therapy: metoprolol 100 mg bid; disopyramide 100 mg x 3; rivaroxaban 20 mg die, insulin. Resting ECG: sinus bradycardia, HR 50 bpm, LVH with secondary repolarization abnormalities, long QTc (>500 ms). At basal and stress echocardiography (Fig. 1) he had a maximum wall thickness at medium IVS of 21 mm and severe dynamic obstruction due to complete SAM (Gmax 50 –> 135 mmHg); moderate mitral regurgitation, secondary to SAM, with eccentric jet; worsening of obstruction and MR at peak of stress (Gmax 145 mmHg; MR 3+); absence of pulmonary hypertension; severe left atrial dilatation (53ml/mq). He was considered not eligible for Morrow myectomy due to unfavorable anatomy (basal IVS of 11–14 mm, maximum thickness at medium IVS). Mitral valve area was > 4cmq. After Heart Team evaluation the patient was proposed for a reparative approach of mitral valve, and TEER was preferred to open surgery for favorable anatomy and to avoid an increased peri–operative risk in a patient with different comorbidities. The procedure was successfully conducted with the implantation of 1 MitraClip (MITRACLIP® Evalve – Abbott) in central position, with echocardiographic evidence (Fig. 2) of complete SAM resolution, reduction of MR to 1+ and gradient abolition (13 mmHg post–Valsalva maneuver). MVA at intraoperative TEE: >2 cmq. At six–months follow–up the patient reported a satisfactory reduction of symptoms without limitations in non–agonist physical activity and work, yet he still was not asymptomatic. Although on best medical treatment and after TEER, transthoracic echocardiographic control showed a recurrence of SAM and LVOTO (40 mmHg at basal, 70 mm Hg post – Valsalva maneuver). He is still candidate to myosin inhibition treatment. This case highlights the multiple challenges of LVOTO in HCM patients. Although a hybrid approach may be a promising treatment of OHCM, especially in youngers, an increase of expertise in this field and further research is needed, focusing on predictors of procedural failure and success.

Medical causes of poor performance and their associations with fitness in Standardbred racehorses.

Poor performance is a multifactorial syndrome of racehorses, commonly associated with subclinical disorders, which can be diagnosed by exercise testing. Describe the prevalence of medical causes of poor performance in Standardbreds unassociated with lameness, and evaluate their relationships with fitness variables measured by exercise treadmill test. Hospital population of 259 nonlame Standardbred trotters referred for poor performance. The horses' medical records were retrospectively reviewed. Horses underwent a diagnostic protocol including resting examination, plasma lactate concentration, treadmill test with continuous ECG and assessment of fitness variables, creatine kinase activity, treadmill endoscopy, postexercise tracheobronchoscopy, bronchoalveolar lavage (BAL), and gastroscopy. The prevalence of different disorders was evaluated, including cardiac arrhythmias, exertional myopathies, dynamic upper airway obstructions (DUAOs), exercise-induced pulmonary hemorrhage (EIPH), moderate equine asthma (MEA), and gastric ulcers (EGUS). The associations of these disorders with fitness variables were investigated individually and using multivariable models. Moderate equine asthma and EGUS were the most common disorders, followed by EIPH, DUAOs, cardiac arrhythmias, and exertional myopathies. Hemosiderin score was positively correlated with BAL neutrophils, eosinophils, and mast cells; increased creatine kinase activity was associated with BAL neutrophilia, DUAOs, premature complexes, and squamous gastric disease. Treadmill velocity at a plasma lactate concentration of 4 mmol/L and at heart rate of 200 beats per minute was negatively affected by BAL neutrophilia, multiple DUAOs, exertional myopathies, and squamous gastric disease. The multifactorial nature of poor performance was confirmed, with MEA, DUAOs, myopathies and EGUS representing the main diseases involved in fitness impairment.

Overview of obstructive sleep apnea treatment

Once diagnosed with obstructive sleep apnea (OSA), a titration with either continuous positive airway pressure (CPAP) or automatic positive airway pressure (APAP) is planned to know the pressure required to abolish the airflow limitation during sleep. Majority of OSA patients are treated with such positive pressure therapy (PAP) devices, but it is not the only form of therapy of OSA. The static obstruction in OSA can be counterbalanced by increasing the pressure from inside and this is being exactly done by PAP therapy. The static obstruction can also be relieved with surgery. IOD (intraoral device) or OPT (oral pressure therapy) is a device which also try to open the upper airway during sleep or prevent collapse. But a dynamic obstruction during sleep, on top of this static obstruction causes complete or partial closure of the upper airway. There are different therapies available to address dynamic obstruction during sleep. Like myofunctional therapy or devices which improve muscle responsiveness are such mode of treatment. Similarly, arousal threshold or loop gain can be addressed with different medications. Sometimes OSA occur only in a particular decubitus and can be addressed with positional therapy. The different form of therapies can be broadly divided into three categories: primary treatment, alternative treatment, and adjunctive treatment. In this review article, a brief description of different forms of therapy in OSA will be presented.

Letter from Norway

Letter from Norway

Unique Approach to Management of Hypertrophic Obstructive Cardiomyopathy within a Resource-Limited Hospital

LVOT obstruction in HCM results from systolic anterior motion (SAM) of the anterior leaflet of the mitral valve and is often a dynamic process (increasing with volume depletion and decreases with volume repletion or afterload augmentation). Hence, understanding the underlying pathophysiological process is crucial in tailoring management decisions. We herein present a case of a 57-year-old female who presented to the emergency department with complaints of shortness of breath (SOB), cough and borderline blood pressure who further decompensated during hospital course, suffering from acute hypotension related to dynamic LVOT obstruction. The patient was managed with a pure α-agonist, phenylephrine. This case report highlights the importance of having a high index of suspicion to early recognize such dynamic LVOT obstruction and further highlights the uniqueness of managing symptomatic hypotension in HCM with LVOT obstruction in an under-resourced hospital.

Cardiac Resynchronization Therapy and Hypertrophic Cardiomyopathy: A Comprehensive Review.

Hypertrophic cardiomyopathy (HCM) is an inherited primary myocardial disease characterized by asymmetrical/symmetrical left ventricle (LV) hypertrophy, with or without LV outflow tract (LVOT) dynamic obstruction, and poor prognosis. Cardiac resynchronization therapy (CRT) has emerged as a minimally invasive tool for patients with heart failure (HF) with decreased LV ejection fraction (LVEF) and prolonged QRS duration of over 120 ms with or without left bundle branch block (LBBB). Several HCM patients are at risk of developing LBBB because of disease progression or secondary to septal myomectomy, while others might develop HF with decreased LVEF, alleged end-stage/dilated HCM, especially those with thin myofilament mutations. Several studies have shown that patients with myectomy-induced LBBB might benefit from left bundle branch pacing or CRT to relieve symptoms, improve exercise capacity, and increase LVEF. Otherwise, patients with end-stage/dilated HCM and prolonged QRS interval could gain from CRT in terms of NYHA class improvement, LV systolic performance increase and, to some degree, LV reverse remodeling. Moreover, several electrical and imaging parameters might aid proper selection and stratification of HCM patients to benefit from CRT. Nonetheless, current available data are scarce and further studies are still required to accurately clarify the view. This review reassesses the importance of CRT in patients with HCM based on current research by contrasting and contextualizing data from various published studies.

Management of severe hypothermia and pulsus alternans in an anaesthetised cat

AbstractAn 8‐year‐old, domestic, shorthair cat was presented for management of a significant degloving injury. After initial wound management, the cat was scheduled for anaesthesia to allow a free skin and pad graft to the affected foot. During anaesthesia, temperature rapidly dropped to a nidus of 28.0°C. Associated with this, the cat developed bradycardia and a marked pulsus alternans. The presumed ventricular myocardial dysfunction was treated with pimobendan (0.15 mg/kg intravenously). Within 5 minutes, the pulses equalised in amplitude. Additional active rewarming measures were initiated, which raised the temperature to 36.4°C before recovery in an incubator. A urinary catheter was placed to monitor for cold diuresis, and fluid therapy was altered to match urine output for 12 hours. A post‐anaesthetic echocardiogram revealed mild left ventricular concentric hypertrophy and dynamic right ventricular outflow tract obstruction indicating mild hypertrophic cardiomyopathy. The cat was discharged following 3 weeks of successful intensive wound and graft management.

Angioarchitecture and prognosis of pediatric intracranial pial arteriovenous fistula

ObjectivePial arteriovenous fistulas (PAVFs) are rare and mostly observed in children. However, the overall angioarchitecture, clinical features, treatments and long-term prognosis for pediatric patients remain unclear.MethodsClinical data of consecutive 42...

大動脈弁逆流と左室流出路狭窄が併発した犬に対して観血的動脈血圧測定を用い術中循環管理を実施した一例

A 12-year-old mix-breed dog was presented with anal sac tumor and scheduled for left anal sacculectomy. Pre-operative echocardiography revealed that the dog had moderate aortic regurgitation (AR), mild mitral valve regurgitation, and dynamic left ventricular outflow tract obstruction. A hypotension of invasive arterial blood pressure (IABP) following low mean and diastolic blood pressure during surgery was suspected to be related to AR and treated by heart rate titration with atropine and dopamine infusion. Accurate blood pressure assessment with IABP and extrapolation treatment strategy of hypotension related to AR by human medicine are useful for anesthetic management in dogs with AR.

Перспективное решение проблемы послеоперационного илеуса в урологии и травматологии

In surgical practice, after operations that directly or indirectly affect the organs of the abdominal cavity, it is possible to develop disturbances in the normal coordinated propulsive motility of the gastrointestinal tract. This condition of dynamic intestinal obstruction is referred to as postoperative gastrointestinal paresis or postoperative ileus (POI). We did not find any information on the frequency of POI in urological practice, however, the frequency of POI in the clinic of colorectal surgery is known to be from 10 to 30% and after gynecological operations 10-15%. The issue of treatment and prevention of POI remains relevant. In global clinical practice, chewing gum has been used after surgery to reduce postoperative intestinal obstruction since the beginning of the 21st century. 141 references were found for the query “postoperative ileus, chewing gum” in the PubMed database alone, of which 53 references to randomized clinical trials, 48 to reviews and systematic reviews, and 26 to meta-analyses. The present review considers randomized clinical trials, systematic reviews and meta-analyzes that examined the prevention of POI in urology and traumatology, indicating the effectiveness and safety of the use of chewing gum in the postoperative period for the prevention of postoperative ileus.

Left atrial myxoma: an unusual cause of pre-syncope and symptomatic bradycardia

BackgroundAtrial myxomas account for approximately 50% of all primary cardiac tumors. The size, location, risk of embolic event, and involvement of other cardiac structures, are all factors that contribute to the wide range of presentation for cardiac myxomas. Patients with myxomas may remain asymptomatic, while others may report symptoms such as fatigue and fever, dyspnea, and syncope. It is important to recognize arrhythmias as an uncommon symptom of myxomas.Case presentationWe report a rare case of a 67-year-old man who presented with pre-syncopal episodes, symptomatic bradycardia, and night sweats found to have a 5.5 × 5.1 × 3 cm myxoma in the left atrium. During diastole the mass caused dynamic flow obstruction across the mitral valve. The patient underwent surgical resection of the mass given his symptomatology and risk of embolic events. Removal of the myxoma resulted in resolution of both pre-syncopal episodes and the patient’s sinus bradycardia.ConclusionAtrial myxomas are a rare cause of pre-syncope and symptomatic bradycardia. It is important to have a clinical suspicion for atrial myxomas given early diagnosis and surgical intervention are key in improving the prognosis of these patients. This case also highlights the importance of taking into account the source of the myxoma’s blood supply in relationship to other cardiac structures, and further correlating these findings with clinical symptoms.

Gas detection in the portal vein after aortobifemoral bypass: a case report

We present a case report of early surgical treatment of abdominal compartment syndrome after aortobifemoral bypass. A 73-year-old man was admitted to the I.I. Mechnikov North-Western State Medical University with critical lower limb ischemia. Aortobifemoral bypass with a synthetic prosthesis was performed via laparotomy. The postoperative period was complicated by the dynamic bowel obstruction. The patient's condition worsened (hypovolemic and septic shock, respiratory failure due to severe pneumonia). Initial tactics was conservative. Signs of bowel ischemia (pneumatosis of the intestinal wall, gas in the portal vein) were identified using “point of care” ultrasound, which led to a change in the treatment tactics. On the same day, decompression relaparotomy was performed and the intestinal decompression tube was inserted. The postoperative period proceeded with positive dynamics: early extubation with acceptable parameters of gas exchange, minimal dosages of vasopressor support. Bowel function improved and stool appeared on the 2nd day after surgery.Gas in the portal vein is an ultrasound phenomenon, which in 70 % of cases suggests necrosis of the intestinal wall. The detection of such a symptom in patients after the abdominal aorta surgery may indicate bowel ischemia, since mesenteric circulation disorders primarily develop in the inferior mesenteric artery. This condition requires urgent surgical intervention, but its differential diagnosis with postoperative paralytic ileus is not always possible, especially in the early stages. We demonstrate a case of early gas detection in the portal vein and the emergency intervention that allowed preventing irreversible ischemic damage of the bowel. “Point of care” ultrasound can help suspect this condition and determine the indications for early surgical intervention, which can positively influence the outcome. Received 19 April 2022. Revised 29 May 2022. Accepted 1 June 2022. Informed consent: The patient’s informed consent to use the records for medical purposes is obtained. Funding: The study did not have sponsorship. Conflict of interest: Authors declare no conflict of interest. Contribution of the authors: The authors contributed equally to this article.

Способ расширяющей кишечной пластики мочевого пузыря у больных с лучевыми пузырно-влагалищными свищами и микроцистисом.

Introduction. Radial vesicovaginal fistulas are one of the most difficult problems of urogynecology, despite the fact that modern technologies make it possible to personalize the use of radiation therapy. Standard surgical techniques in the treatment of such patients are ineffective. The search for alternative surgical solutions can improve the results of treatment of patients with radial fistulas and microcystis. Study objective. To compare the effectiveness of augmentation ileocystoplasty and two-stage surgical treatment, represented by expanding intestinal cystoplasty in combination with the use of a Martius or Martius-Symmonds flaps. Materials and methods. The study included 8 patients. The first group included 4 patients who underwent laparotomy, augmentation ileocystoplasty. In 3 patients relapsed fistulas were closed with vaginal access using a Martius flap a few months later. The second group included 4 patients who underwent expanding intestinal cystoplasty by laparotomy, with further formation of Martius or Martius-Symmonds flaps by perineal access and moving them into the pelvic cavity for fixation from the abdominal cavity. Results. The average duration of the operation in the first group was 337.5 minutes, in the second group – 470 minutes. The patients of the first group had no complications of the III-V groups according to Clavien-Dindo. Natural urination was eventually recovered in all patients. In 2 patients of the second group, postoperative complications were recorded: in 1 patient – complication of group IIIa according to Clavien-Dindo – marginal necrosis of the skin flap after abdominoplasty, which required stage necrectomy and secondary skin sutures, in another 1 patient – complication of group IIIb according to Clavien-Dindo – dynamic intestinal obstruction, which required relaparotomy and nasointestinal intubation. There were no relapses of vesicovaginal fistulas. After urination was restored, all patients retained the urge to urinate. Conclusion. The proposed two-stage operation allows not only to eliminate the vesicovaginal fistulas, but also to increase the capacity of the bladder, restore voluntary urination.

A Computational Study of Dynamic Obstruction in Type B Aortic Dissection.

A serious complication in aortic dissection is dynamic obstruction of the true lumen (TL). Dynamic obstruction results in malperfusion, a blockage of blood flow to a vital organ. Clinical data reveal that increases in central blood pressure promote dynamic obstruction. However, the mechanisms by which high pressures result in TL collapse are underexplored and poorly understood. Here, we developed a computational model to investigate biomechanical and hemodynamical factors involved in Dynamic obstruction. We hypothesize that relatively small pressure gradient between TL and false lumen (FL) are sufficient to displace the flap and induce obstruction. An idealized fluid-structure interaction model of type B aortic dissection was created. Simulations were performed under mean cardiac output while inducing dynamic changes in blood pressure by altering FL outflow resistance. As FL resistance increased, central aortic pressure increased from 95.7 to 115.3 mmHg. Concurrent with blood pressure increase, flap motion was observed, resulting in TL collapse, consistent with clinical findings. The maximum pressure gradient between TL and FL over the course of the dynamic obstruction was 4.5 mmHg, consistent with our hypothesis. Furthermore, the final stage of dynamic obstruction was very sudden in nature, occurring over a short time (<1 s) in our simulation, consistent with the clinical understanding of this dramatic event. Simulations also revealed sudden drops in flow and pressure in the TL in response to the flap motion, consistent with first stages of malperfusion. To our knowledge, this study represents the first computational analysis of potential mechanisms driving dynamic obstruction in aortic dissection.

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.

786 SYSTOLIC ANTERIOR MOVEMENT OF MITRAL VALVE: NOT ONLY HYPERTROPHIC CARDIOMYOPATHY, BUT ALSO CARDIAC AMYLOIDOSIS

Abstract A 71 years-old man was diagnosed with lambda light chain multiple myeloma evolving from monoclonal gammopathy of unknown significance during hematological follow-up. Serum creatinine and blood urea were normal, but proteinuria was significant. A subsequent renal biopsy showed amyloid deposits in renal glomeruli. He had no comorbidities or previous cardiologic history. To provide a complete diagnostic work-up, an echocardiogram was performed, showing marked and asymmetric left ventricular hypertrophy (interventricular septum diastolic thickness IVSd 15 mm) with dynamic left ventricular outflow tract obstruction (LVOTO) due to an incomplete systolic anterior motion (SAM) of mitral valve. ECG showed sinus rhythm with 1st degree atrio-ventricular block; notably, there was no electrocardiographic sign of left ventricular hypertrophy. Therefore, a Cardiac Magnetic Resonance (CMR) was performed, showing left ventricular hypertrophy (interventricular septum thickness 15 mm) with normal contractility. Mild left atrial enlargement and thickening of the interatrial septum were found, together with mild circumferential pericardial effusion. No perfusion defects were recorded, but late gadolinium enhancement (LGE) pattern was not assessable because of difficult myocardial signal nulling point. These findings were consistent with cardiac amyloidosis (CA). By the time, histological demonstration of amyloid was mandatory, so an endomyocardial biopsy was performed. Amyloid deposits were found to be in the myocardial interstitial space and into the myocardial vessel walls. Immunohistochemical staining revealed diffuse and high reactivity for lambda free light chains and moderate reactivity for kappa chains. No transthyretin was found in the specimens. Finally, a diagnosis of AL amyloidosis with cardiac and renal involvement associated with lambda light chain multiple myeloma was made and chemotherapy with bortezomib, thalidomide and dexamethasone (VTD) was started. During the cardiologic follow-up, three syncope with prodromal symptoms have occurred. In all these circumstances, no arrhythmias were found at prolonged ECG Holter monitoring. Echocardiogram showed a progression of the dynamic outflow obstruction to 80 mmHg and increasing mitral regurgitation associated with complete systolic anterior motion of the valve. Given the echocardiographic features and the clinical events, we performed a genetic blood test which excluded sarcomeric genes mutations. Also, familial screening with ECG and echocardiogram was negative. A better management of pharmacological therapy, together with avoidance of hypovolemia and supportive treatment of anemia finally relieved patient's symptoms. Conclusions we presented this case to underline that, although rare, cardiac amyloidosis can resemble other hypertrophic cardiomyopathies with left ventricular outflow tract obstruction due to SAM of the mitral valve and irregular septal hypertrophy, caused by amyloid deposits. Most of these cases are seen in the senile transthyretin type, but sometimes they are observed in AL patients. Nowadays, it is crucial to diagnose these patients correctly as early treatment is critical for survival in this population.