Aortic Leaflets Research Articles

Aortic regurgitation in bicuspid aortic valve: know to decide

Abstract Funding Acknowledgements Type of funding sources: None. Chronic aortic regurgitation (AR) is the second cause of valve surgery in patients with bicuspid aortic valve (BAV) and has distinctive characteristics of trileaflet regurgitation. The quantification variables of aortic regurgitation do not take into account the unique characteristics of bicuspid regurgitation. Recognition of the mechanisms that lead to bicuspid AR is relevant as it allows correct treatment planning and valve repair in candidate patients. Objective a prospective study was designed to identify the mechanisms of AR and the factors (clinical and anatomical) associated with the development of significant AR (moderate/severe) in adult patients with BAV. Materials and methods We included consecutive adult patients with a confirmed diagnosis of BAV evaluated between 2014 and 2021 with at least 3 years of follow-up by the Structural Heart Disease group of our institution. Valve disease was evaluated by echocardiography and complementary methods. It was classified as mild, moderate (Mod), and severe (Sev) aortic regurgitation, according to current criteria (integral approach with quantitative and semi-quantitative criteria). The prevalence of regurgitation mechanisms, the progression of aortic regurgitation, and predictive variables of significant AR and major cardiovascular events (death, surgery) were analyzed using univariate and multivariate analyses. A p<0.05 was considered significant. Surgery was indicated following international recommendations (ESC guidelines): symptoms development or ventricular dysfunction. Results We included 300 patients (39.7 ± 14.9 years, 72.6% men). Regarding valvular phenotype 84% (257p) presented fused BAV (coronary leaflets) and the majority with raphe (87.5%). 71.7% of the patients had some degree of aortic regurgitation at the start of follow-up (24.1% Mod/Sev AR). Among the patients with significant AR, 50% had cusp prolapse (86% prolapse of the fused leaflet), 39.18% dilatation of the aortic root, 26.6% significant calcification of the valve, 1.3% valve perforation and 29.4% restriction of valve movement. 43% with Mod/Sev AR had mixed mechanisms of regurgitation and the combination, half represented by the combination of aortic root dilatation and cusp prolapse (Fig 2). During follow-up 18–6% of patients with Mod AR showed progression to Sev AR and 4.7% underwent surgery. On the other hand, 34.1% of patients with baseline Sev AR required aortic valve surgery (p<0.01). Conclusions In our cohort, AR was highly prevalent: 1 out of 4 patients had significant AR at the start of follow-up. Eccentric jets and the presence of valve prolapse were frequent in patients with significant AR. 43% of BAV patients with Mod/Sev AR exhibited mixed regurgitating mechanisms. Because mechanism affects the choice of surgical technique, comprehensive mechanism description is critical in patients with BAV and AR.

Surgical aortic valvuloplasty is a better primary intervention for isolated congenital aortic stenosis in children with bicuspid aortic valve than balloon aortic valvuloplasty

ObjectivesSurgical aortic valvuloplasty (SAV) and balloon aortic valvuloplasty (BAV) are two main treatments for children with isolated congenital aortic stenosis (CAS). We aim to compare the two procedures' midterm outcomes, including valve function, survival, reintervention, and replacement. MethodsFrom January 2004 to January 2021, children with isolated CAS undergoing SAV (n = 40) and BAD (n = 49) at our institution were included in this study. Patients were also categorized into subgroups based on the aortic leaflet number(Tricuspid = 53, Bicuspid = 36) to compare the two procedures’ outcomes. Clinical and echocardiogram data were analyzed to identify risk factors for suboptimal outcomes and reintervention. ResultsPostoperative peak aortic gradient (PAG) and PAG at follow-up in the SAV group were lower compared with the BAV group (p < 0.001, p = 0.001, respectively). There was no difference in moderate or severe AR in the SAV group compared with the BAV group before discharge (5.0% vs 12.2%, p = 0.287) and at the last follow-up (30.0% vs 32.7%, p = 0.822). There were no early death but three late deaths (SAV = 2, BAV = 1). Kaplan-Meier estimated survivals were 86.3% and 97.8% in SAV and BAV groups respectively at 10 years (p = 0.54). There was no significant difference in freedom from reintervention (p = 0.22). For patients with bicuspid aortic valve morphology, SAV achieved higher freedom from reintervention (p = 0.011) and replacement (p = 0.019). Multivariate analysis indicated that residual PAG was a risk factor for reintervention (p = 0.045). ConclusionsSAV and BAV achieved excellent survival and freedom from reintervention in patients with isolated CAS. SAV performed better in PAG reduction and maintenance. For patients with bicuspid AoV morphology, SAV was the preferred choice.

Post-infarction revelation of the inflammatory bicuspid aortic cusp perforation to the intraventricular septum pseudoaneurysm cavity.

Post-infarction revelation of the inflammatory bicuspid aortic cusp perforation to the intraventricular septum pseudoaneurysm cavity.

Surgical outcomes of aortic valve repair for specific aortic valve cusp characteristics; retraction, calcification, and fenestration

ObjectivesWe investigated the predictive value of aortic valve cusp retraction, calcification, and fenestration for aortic valvuloplasty feasibility. MethodsMulticenter data were collected for 2082 patients who underwent surgical aortic valvuloplasty or aortic valve replacement. The study population had retraction, calcification, or fenestration in at least one aortic valve cusp. Controls had normal or prolapsed cusps. ResultsAll cusp characteristics demonstrated significantly increased odds ratios [ORs] for switch to valve replacement. This effect was strongest for cusp retraction, followed by calcification and fenestration (OR, 25.14; P ≤ .001; OR, 13.50, P ≤ .001; OR, 12.32, P ≤ .001). Calcification and retraction displayed increased odds for developing grade 4 aortic regurgitation compared with grade 0 or 1 combined on average over time (OR, 6.67; P ≤ .001; OR, 4.13; P = .038). Patients with cusp retraction showed increased risk for reintervention at 1- and 2-year follow-up after aortic valvuloplasty (hazard ratio, 5.66; P ≤ .001; hazard ratio, 3.22, P = .007). Cusp fenestration was the only group showing neither an increased risk of postoperative severe aortic regurgitation (P = .57) or early reintervention (P = .88) compared with the control group. ConclusionsAortic valve cusp retraction, calcification, and fenestration were all related to increased rates of switch to valve replacement. Calcification and retraction were associated with recurrence of severe aortic regurgitation. Retraction was related to early reintervention. Fenestration was neither associated with recurrence of severe aortic regurgitation or reintervention. This indicates that surgeons are well able to distinguish aortic valve repair candidates in patients with cusp fenestration.

Non-invasive electrocardiographic ventricular mapping based on the equivalent double layer model: different workflows, same accuracy

Abstract Funding Acknowledgements Type of funding sources: None. Background and aim Electrocardiographic imaging (ECGI) is capable of performing activation maps with a single premature beat. The endo-epicardial ECGI system based on the equivalent double layer model (EDL), is a portable system that uses a patient-specific heart torso geometry obtained from a CT-scan or cardiac magnetic resonance (CMR), and a conventional 12-lead ECG. The simplicity of the system allows for its use either as a pre-procedural or intra-procedural tool. The aim of this study was to assess the accuracy of the system in centres using different workflows. Methods We studied consecutive patients referred for ablation of ventricular arrhythmias that had an ECGI performed with the endo-epicardial system based on the EDL model to guide mapping and catheter ablation, at four centres. Three centres performed the ECGI pre-procedurally, two with the use of a bedside portable ECG recorder and one on ambulatory basis with a 12-lead Holter recorder, and ablation was performed either manually or with remote magnetic navigation (RMN). The fourth centre performed the ECGI intra-procedurally, recording the ECG directly from the electrophysiology digital multichannel system, and the ablation was performed manually with the use of intracardiac echo (ICE) in all cases. VAs were localised using a segmental model, which included 22 left ventricular segments (classical 17-segment model, plus the aortic cusps and the papillary muscles), and 12 segments on the right ventricle including 4 on the right ventricular outflow tract (RVOT): Anterior, lateral, right septum and left septum. A perfect match (PM) was defined as a predicted location within the same anatomic segment, whereas a near match (NM) was defined as a predicted location within the same segment or a contiguous one. We studied the three different workflows. Results Sixty-three arrhythmias were studied in 58 patients. The ECGI was performed pre-procedurally with a bedside ECG recorder in 26 cases, pre-procedurally with a Holter recorder in 27 cases and intra-procedurally in 10 cases. The results according to each group are presented in the Table. The accuracy of the ECGI was not different between groups. The system correctly identified the SOO of the VAs in the same or a contiguous segment when compared to the invasive mapping in all patients, regardless of the approach used. The percentage of PM was also not significantly different. The group with ICE guidance had lower fluoroscopy and mapping times, but the success and recurrence rates were similar. Conclusions The results of this multicentre experience show that this ECGI system, using a conventional 12 -lead ECG is simple and accurate across different clinical workflows, and presents a useful and versatile tool to facilitate planning the ablation strategy as well as intra-procedural guidance for mapping and ablation of patients with VAs.

Efficacy and safety of catheter ablation of VT using the QDOT Micro catheter: a propensity-matched dual-center comparison with the thermocool SmartTouch catheter

Abstract Funding Acknowledgements Type of funding sources: None. Background Catheter ablation is an increasingly used treatment option for patients with recurrent ventricular tachycardia (VT) or electrical storm (ES). The QDOT Micro (QDOT) Catheter (Biosense Webster) is a novel radiofrequency ablation catheter that was found to allow rapid and effective pulmonary vein isolation among patients with atrial fibrillation. There is no published data on the safety and efficacy of catheter ablation for VT using the QDOT catheter, and few data allow a direct comparison of different technologies in this setting. Purpose to assess outcomes of CA for VT among patients with structural heart disease using the QDOT catheter, and compare them to those observed with the Thermocool Smarttouch (TC-ST, Biosense Webster) catheter. Methods we conducted a dual-center, observational, prospective study enrolling patients with structural heart disease and recurrent VT/ES undergoing catheter ablation with the QDOT catheter. For comparison, we performed a 1:1 propensity score matching to identify patients who underwent VT CA with the TC-ST catheter, using the nearest neighbor method. Propensity score was based on gender, age, etiology of structural heart disease, left ventricular ejection fraction, electrical storm, and number of previous CAs for VT. The primary efficacy outcome was freedom from recurrent VT, as assessed by implantable defibrillator (ICD) interrogation; the primary safety outcome was in-hospital complications. Results Forty propensity-matched patients were included in the analysis (QDOT, n=20; TC-ST, n=20); baseline clinical characteristics are resumed in Table. After a median follow-up of 7 months, survival free from any recurrent VT measured 74 (95% CI, 57-97)% and 69 (95% CI, 51-93)% in the QDOT and TC-ST groups, respectively (log-rank p=0.54, Figure A), while survival free from ICD shocks was 95 (95% CI, 86-100)% versus 84 (95% CI, 69-100)% (log-rank p=0.26, Figure B). There were no major complications in the QDOT group, while three patients (15%) in the TC-ST had a primary safety event (p=0.23; femoral pseudoaneurysm, n=1; cardiac tamponade, n=1; aortic cusp perforation, n=1). Conclusion In a cohort of patients with structural heart disease and recurrent VT or ES, the novel QDOT ablation catheter had similar efficacy and safety compared to the TC-ST catheter. Interestingly, no major procedural complications were observed with the QDOT catheter, suggesting that this device may be safe even in most challenging patients.

C35 A RARE CASE OF NON–BACTERIAL THROMBOTIC ENDOCARDITIS IN YOUNG WOMAN AFFECTED BY ADVANCED UTERINE CANCER

Abstract A 37–year–old woman affected by uterine HPV–related adenocarcinoma complicated by paraneoplastic pulmonary thromboembolism, came to the emergency department for recurrent episodes of dysarthria and blurred vision with spontaneous resolution. Home medications: Enoxaparin 5000 UI b.i.d, levofloxacin 500 mg/die, deltacortene 25 mg/die and omeprazole 20 mg/die. Blood analysis: normocytic anemia (Hb 9 gr/dl),elevated D–dimer (22.5 mcg/ml) and elevated C–reactive protein (18.3 mg/dl). Procalcitonin and blood cultures resulted negative. Brain CT scan: ischemic brain lesions of embolic nature in the right precentral gyrus and in the left post central gyrus. EKG: sinus rhythm, T–wave inversion in inferior leads. In the suspect of cardioembolic stroke a transthoracic (TTE) and subsequent transesophageal (TOE) echocardiography was performed: TTE: isoechoic oval–shaped thickening of the aortic valve cusp tips, producing aortic regurgitation with double jet regurgitation. TOE: evidence of multiple isoechoic masses involving all the aortic cusps, without perivalvular aortic extension, producing significant aortic regurgitation due to coaptation– gap (Figure 1). The diagnosis of non–bacterial thrombotic endocarditis (NBTE) was made up. Although the standard medical therapy (anticoagulation and chemotherapy) was promptly started, it wasn’t effective with progression of the disease leading to surgical indications of valve intervention. The patient underwent aortic valve replacement with bioprosthesis avoiding mechanical prosthesis, despite the young age, in anticipation of major surgery for the uterine cancer. Surgical specimen turned negative for microorganism growth confirming the diagnosis of marantic endocarditis. No further episodes of ischemic stroke appeared after the replacement of the valve and the patient had no neurological sequelae. NBTE is a rare condition of non–infective endocarditis characterized by the formation of aggregates of platelets and fibrin that affects usually undamaged heart valves in the absence of bacteremia and mostly occurs in patients with a predisposing state like hypercoagulability. Surgical indications of valve intervention are not well encoded but in most cases they follow the raccomandations for infective endocarditis. Our experience highlights the need of a prompt intervention in order to reduce the damage of systemic embolization and preserve patient’s hemodynamics with a strict checking of disease progression.

P295 WHEN TAVI IS THE RIGHT CHOICE

Abstract Clinical case We describe a case of a 62–y–old man, affected by hypertension, insulin–dependent diabetes mellitus, advanced liver cirrhosis. After screeing, the patient was listed for liver transplantation. On September 2022, the patient was admitted to our Emergency Room due to HF in class NYHA III. The transthoracic echocardiogram showed a severe aortic regurgitation with mobile vegetations, the largest of which is more than 10 mm on the right aortic cusp. Normal biventricular function was observed with sPAP of 45 mmHg. Thus, we concluded for post–endocarditis severe aortic regurgitation. We discussed tha case in our Department Heart Team with the concomitant presence of the Liver Team. We considered the patient at high surgical risk, mostly due to the risk of postoperative hepatic insufficiency. So, we decided for a TAVI off–label. So, we impantanted a Sapien 3 Ultra 26 mm through transfemoral access. To reduce the risk of cerebral embolization, we used Triguard 3 system, while to prevent coronary embolization we used a closed stent into the right coronary ostia, ready to be opened. The patient was discharged in the fourth postoperative day, without conduction disturbances. The postoperative echo showed normal valvular function and absence of paravalvular leakages. Conclusions Patients with advanced liver cirrhosis are at risk of organ failure following use of extracorporeal circulation. In selected patients, TAVI may be a valid alternative. The peculiarity of the specific case was due to the use of the TAVI in an off–label procedure of aortic insufficiency with the simultaneous presence of mobile vegetation at high embolic risk.

P406 LAUBRY–PEZZI SYNDROME: EVERYTHING IS NOT AS IT SEEMS

Abstract Introduction Laubry–Pezzi syndrome is a congenital heart disease characterized by the prolapse of an aortic valve cusp into a subjacent ventricular septal defect (VSD), mostly supracristal, leading to severe aortic regurgitation (AR). It has been reported nearly always in childhood, the Venturi effect is the predominant factor and onset symptoms may be variable. Case Report A 61–years–old male was admitted to our intensive case unit for chest pain radiated to interscapular region and exertional dyspnea. Hemodynamic parameters were normal. At ECG sinus rytm with heart rate 92 bpm and non–specific repolarization abnomalities were reported. Hs troponin I was 276 ng/L, myoglobin 30.2 ng/mL and BNP 325 pg/mL. Transthoracic echocardiography showed a dilated left ventricle (LV EDV 107 mL/m2) with normal ejection fraction (55%), severe AR without aortic root dilation and a suspicious shunt left to right at level of interventricular septum. Therefore, transesophageal echocardiography was performed and confirmed severe AR by probable bicuspid valve and right cusp prolapse, in absence of calcifications and/or vegetations by endocarditis, restrictive perimembranous VSD (maximum diameter 0.6 cm) and ostium secundum ASD with shunt L–R. Right chambers were not dilated and non invasive systolic pulmonary artery pressure was 43 mmHg. Coronary angiography was performed and showed a significant stenosis of distal left anterior descending (LAD) artery and of proximal circumflex artery. Right heart catetherization excluded significant high values of pulmonary pressures (mPAP=18 mmHg), of pulmonary capillary wedge pressure (9 mmHg), with a mild increase of pulmonary vascular resistances (1.16 HRU; nv &amp;lt; 96). Coronary artery bypass grafting (left internal mammary artery on LAD and Y–graft radial artery on obtuse marginal artery), aortic valve replacement with bioprothesis (Inspiris Resilia 23 mm), ASD closure by direct suture and VSD closure with pericardial patch were performed. No post–surgical complications were reported. Interestingly, during the replacement of aortic valve, it resulted tricuspid, confirming the suspicion of Laubry Pezzi syndrome. Conclusions our case was object of great debate because restrictive VSD and severe AR were not previously known, were diagnosed in middle age and until then paucisymptomatic. Laubry–Pezzi syndrome is a very rare disease that may explain controversial cases of severe AR.

P98 A CASE OF “RECURRENT” AORTIC VALVE STENOSIS

Abstract Clinical Case A 80–year–old man underwent coronary angiography in 2006 because of stable angina. There was chronic total occlusion of middle left anterior descending artery requiring percutaneous intervention. In 2009 he underwent coronary angiography for recurrent angina: a severe stent restenosis was treated with stenting in stent (DES in BMS). The patient was subsequently asymptomatic till 2018 when he complained of exertional dyspnea and angina. Stent patency and severe aortic valve stenosis (AVA 0.85 cm2) were documented. The patient underwent successful transcatheter aortic valve implantation and discharged with dual antiplatelet therapy (DAPT) (Asa 100 mg and Clopidogrel 75 mg). Clinical and echocardiographic follow–up was unremarkable (mean prosthetic gradient 17 mmHg, DVI=0.45). In July 2021 during a cardiological check the patient complained of bruising: ASA was discontinued. In February 2022 the patient suffered from an exertional angina. A dipyridamole stress–echocardiography failed to demonstrate inducible ischemia, although the patient experienced angina at the peak load step. Transthoracic echocardiogram (TTE) revealed high mean trans–prosthetic aortic gradient (52 mmHg, DVI=0.18). A trans–esophageal echocardiogram (TEE) showed reduced mobility of the thickened left coronary and non–coronary aortic prosthetic leaflets. In the hypothesis of prosthetic valve thrombosis, warfarin (INR range 2–3) was started after stopping clopidogrel. After three months a TTE showed normalized mean trans–prosthetic gradients (17 mmHg, DVI=0.5). When a 6 month–period of anticoagulant therapy was accomplished, warfarin was stopped and DAPT administered again. In September 2022 the patient complained of worsening dyspnea and chest pain on exertion. At TTE mean trans–prosthetic gradients (46 mmHg) was increased. A new TEE showed thickening of non–coronary and right coronary leaflets, suggestive of recurrent valve thrombosis. After stopping DAPT, warfarin was started again with good result (mean prosthetic gradient 12 mmHg, DVI=0.5). Conclusion Thrombosis of aortic valve prothesis is an infrequent event usually occurring in early post–implantation period. In our case it occurred four years after implantation following DAPT interruption. The likely initial prosthetic valve degeneration together with a simplification of DAPT may have had a causative role. Since the proved efficacy of warfarin and the limited experience of DOAC in this field, the patient was given warfarin sine die.

P269 AORTA–RIGHT ATRIAL TUNNEL POST TRICUSPID ANNULOPLASTY

Abstract Background Aorta–right atrial tunnel is a rare entity characterized by a iatrogenic vascular fistula, which connects aortic root and right atrium. It is frequently associated with congestive heart failure (HF). Case A 54 y female with an history of atrial septal defect (ASD) type ostium secundum closure and a recent mitral and tricuspid annuloplasty surgery, presents to the hospital with significant decrease in exercise tolerance and progressive shortness of breath. At the presentation, physical examination was significant for tachycardia, continuous murmur over precordium and lower extremity edema. ECG showed right ventricular pressure overload with repolarization abnormality. TTE showed moderate systolic flattening of the septum and dilated right sections. Non coronary cusp of aortic valve demonstrated a perforation extending to the right atrium (RA). ETE confirmed the connection between non–coronary aortic cusp and RA, furthermore revealed unkown sinus venosus type ASD. TC angiography showed a marked dilation of the pulmonary artery trunk (egg and banana sign) and a connection between aorta and RA. She was treated with surgical closure of aorta– right atrial tunnel and ASD through detached and pledget stitch closure. Follow–up reveals significant functional recovery of shortness of breath and exercise tolerance. Discussion Aorta– right atrial tunnel is a rare entity characterized by a vascular fistula, which connects one of the sinuses of Valsalva and the RA. It is a rare complication of tricuspid plastic surgery. It is classified according to its relation to the aorta to anterior or posterior. The clinical presentation ranges from asymptomatic continuous murmur to the symptoms of right sided HF. In our case, the presence of ASD accelereted and worsened the manifestations of right HF. It is usually diagnosed by TTE or ETE, TC angiography and aortography. The treatment of this condition is important even in asymptomatic cases due to the risk of aortic valve dysfunction, likely regurgitation, congestive right sided HF followed by left sided HF, calcification, infective endocarditis, aneurysmal dilatation and pulmonary hypertension. Conclusion The possibility of complications of aorta–right atrium fistula necessitates early therapy, even in asymptomatic patients or those with a hemodynamically insignificant shunt. Available treatment is surgical closure. It has a high mortality rate if it is not diagnosed adequately and surgically treated without delay.

C21 A FLOATING THROMBUS IN THE ASCENDING AORTA, AS A COMPLICATION OF A PERCUTANEOUS CORONARY ANGIOGRAPHY

Abstract Free–floating thrombus of the ascending aorta is a rare disease entity which carries a potential risk of distal embolization with catastrophic consequences. We present the case of a 46–year–old patient with floating thrombus in the ascending aorta, likely caused by catheter injury, after a percutaneous coronary angiography with stent implantation at the circumflex artery and no antiplatelet agents. A 46–year–old female patient was admitted to the emergency room with acute chest pain radiating to the left arm for the past 3 days. She reported a history of cigarette smoking and a ST–elevation myocardial infarction with stent implantation at the level of the circumflex artery about 1 month before. The patient was not taking any antiplatelet therapy for explicit refusal. Transthoracic echocardiography showed an isoechoic lesion in the ascending aorta and no other abnormalities of the cardiac structure and function and of the valve systems. Transoesophageal echocardiography confirmed the presence of a coarse (17 mm 14 mm) isoechoic formation, with a large base of implantation at the level of the non–coronary aortic cusp, extending approximately 45 mm into the aortic vessel with a floating attitude (Panels A–C). Computed tomography angiography showed a pedunculated mass measuring 22 mm 22 mm 45 mm in ascending aortic lumen (Panels D and E). Intact intima and normal size of ascending aorta with no signs of aortic dissection or intramural haematoma were also reported. The patient underwent a thrombectomy (Panel F) and aortic replacement. A histopathologic examination revealed the mass to be a fibrin thrombus. The post–operative course was uneventful. No recrudescence or concomitant visceral or vascular embolism was observed. The patient was discharged with dual antiplatelet agents.

Non-coronary Aortic Cusp Rupture in a Child with Ventricular Septal Defect and Aortic Valve Prolapse

Non-coronary Aortic Cusp Rupture in a Child with Ventricular Septal Defect and Aortic Valve Prolapse

Antagonizing interleukine-8 improves the durability of biological aortic valves: Translation of fundamental results using a model of subcutaneous aortic valve implantation in rats into clinical application such as cardiac surgery

Aortic valvle stenosis is a common disease, only surgical therapy is recommended. Using the model of subcutaneous aortic valve implantation in rats described first time by Fishbein et al. in 1982, we test the hypothesis that antagonizing Interleukine-8 (IL-8) receptors reduces calcification of the pig aortic valves. Pigs Hearts were explanted directly from the slaughter house. Aortic valvular leaflets were then implanted subcutaneously within 4 hours on the back of Sprague Dawley young rats. Every day for a total period of 14 days, rats received either local subcutaneous injection either intra-peritoneal injection of drug, either none drug. The drug was SCH527123, which is an antagonist of CXCR-1 and CXCR-2, receptors of IL-8. The 3 groups were sacrificed at the end of 14 days after a blood sampling and the aortic valvular leaflets were explanted to be analyzed. The analysis consisted of immuno-histochemistry coloration, calcium dosage and western-blot analysis. GA increases calcification. Inflammation is present highly concomitant with calcification. Macroscopical findings confirm the part of red blood cells in the mechanism of calcification. Parallel with clinical results can be made as the age of patient. The use of antagonist of CXCR-1 or CXCR-2 in the treatment of pre-incubation of bioprosthesis or oral prescriptions concomitant of the aortic valve replacement may be a lead for improving the durability of aortic bioprosthesis.

PO-05-073 CHARACTERISTICS OF BIPOLAR AND UNIPOLAR ELECTROGRAMS AT SUCCESSFUL ABLATION TARGETS FOR VENTRICULAR ARRHYTHMIA ORIGINATING FROM THE VICINITY OF LEFT VENTRICULAR SUMMIT

Successful elimination of idiopathic ventricular arrhythmias from the vicinity of left ventricular summit could frequently be achieved from aortic cusps, endocardial or epicardial ablation. To explore whether the characteristics of bipolar and unipolar electrograms recorded from the vicinity of left ventricular summit could guide the appropriate site for successful ablation. Patients with idiopathic ventricular arrhythmias from the vicinity of left ventricular summit who underwent endocardial and epicardial mapping/ablation were retrospectively studied. Patients with structural heart disease or reentrant ventricular arrhythmias were excluded. Electrograms of the earliest activation sites in different anatomical structures, including great cardiac vein/anterior interventricular vein (GCV/AIV), supravalvular, subvalvular area, and/or right ventricular outflow tract (RVOT) were extracted for analysis. In total, 55 patients (median age 59 years, 42 men) and 163 mapping points were analyzed. These mapping points were located in GCV/AIV (n = 44), supravalvular area (n = 42), subvalvular area (n = 45), or the RVOT (n = 32). A pre-potential was identified at 17 (10.4%) points, while a unipolar QS morphology at 69 (42.3%) points. Successful ablation was achieved at 37 points. The presence of a pre-potential and the bipolar local activation time (LATBi) have a predictive value for successful ablation. In contrast, neither the unipolar LAT (LATUni), difference between LATBi and LATUni, presence of a unipolar QS morphology, nor the slope and interval of the unipolar descending limb could predict success. Earliest bipolar local activation and the presence of a pre-potential provide good surrogates to predict successful ablation of idiopathic ventricular arrhythmias originating from the vicinity of left ventricular summit.

Laubry-Pezzi syndrome: three case reports and review of the literature.

We reported three cases of Laubry-Pezzi syndrome diagnosed in our department of cardiology on a cohort of more than 3000 cases of congenital heart disease. A 13-year-old patient presented a Laubry-Pezzi syndrome with severe AR and significant volumetric left ventricle overload and was operated on in time to allow a good evolution of his condition. A 43-year-old patient, followed for congenital cardiac pathology, presented with severe dyspnea. The echocardiogram found global dysfunction of the left ventricle with an ejection fraction of 35%, a perimembranous ventricular septal defect (VSD) almost completely closed by the prolapse of the noncoronary cusp, and severe eccentric aortic insufficiency due to the prolapse of the noncoronary cusp. Aortic valve replacement and VSD closure were indicated. The third patient is a 21-year-old patient with Down syndrome, in whom a grade 2/6 systolic murmur was detected. Transthoracic echocardiography revealed a perimembranous VSD measuring 4mm without any hemodynamic repercussions and a moderate aortic insufficiency due to the prolapse of the noncoronary cusp. Clinical and echocardiographic monitoring with Osler prevention was indicated as a modality of management. The pathophysiology is explained by the Venturi effect, the restrictive shunt of the VSD creates an area of low pressure that sucks the adjacent cusp resulting in aortic prolapse and regurgitation. The diagnosis is essentially based on transthoracic echocardiography; it must be conducted before the emergence of AR. The management of this rare syndrome still remains nonconsensual, whether it is through timing or operative techniques. Management must be early by closing the VSD with or without aortic valve intervention to prevent the onset or worsening of AR.

PO-05-097 FIRST REPORT OF CRYOABLATION OF NON-PAPILLARY MUSCLE PVCS UNDER DIRECT VISUALIZATION DURING MV REPAIR: INTER-LEAFLET TRIANGLE AND THE AORTO-MITRAL CONTINUITY

Up to 60% of patients with mitral valve prolapse (MVP) have premature ventricular contractions (PVC), usually of papillary muscle (PM) origin. However, one-third of PVCs are of non-PM origin, from areas exposed to annular stress forces. We have previously demonstrated the feasibility of intraoperative cryoablation of PM PVCs under direct visualization during mitral valve (MV) repair. To our knowledge, this is the first report of a similar approach for non-PM PVCs. We present two cases of visually-guided surgical cryoablation of non-PM PVCs at the time of elective MV repair. Both were guided by ECG morphology criteria and hybrid PET/MRI imaging pre-operatively. n/a Case 1 (Figure): 73 year old female with degenerative MVP, severe MR and frequent PVCs (27%). There were two PVC morphologies: the dominant PVC was suggestive of interleaflet triangle (ILT) origin (abrupt V3 transition), and the less frequent PVC was consistent with postero-medial PM origin. Hybrid PET-MRI demonstrated focal uptake of FDG in the LV summit region just under the aortic valve. The patient underwent an uncomplicated MV repair, TV repair and cryoablation of the ILT (open endocardial retrograde approach) and then the posterior PM. Follow up TTE showed normal MV and aortic leaflets function without regurgitation or stenosis. An event monitor at 2 months post-op revealed a PVC burden of 2% (off drugs). Case 2: 76 year old male with degenerative MVP, severe mitral regurgitation (MR) and frequent symptomatic PVCs (24%), suggestive of an aortomitral continuity (AMC) origin. Simultaneous cardiac 18F FDG-PET and MRI with LGE imaging demonstrated focal uptake of FDG in the AMC region, no LGE was detected. The patient underwent an uncomplicated MV repair, TV repair and cryoablation of the AMC. The cryo-application was performed on the atrial side of the mitral annulus with forward pressure to reach the ventricular myocardium. There were no PVCs during post-op monitoring and a 6-month follow-up monitor revealed a PVC burden of 1% (off drugs). Surgical cryoablation of non-PM PVCs under direct visualization at the time of MV surgery, using standard ECG criteria and pre-op Hybrid PET-MRI imaging, is feasible. Further studies are needed to determine the safety and effectiveness of adjunctive PVC cryoablation at the time of MV surgery.

3D histopathology of stenotic aortic valve cusps using ex vivo microfocus computed tomography.

Calcific aortic stenosis (AS) is the most prevalent heart valve disease in developed countries. The aortic valve cusps progressively thicken and the valve does not open fully due to the presence of calcifications. In vivo imaging, usually used for diagnosis, does not allow the visualization of the microstructural changes associated with AS. Ex vivo high-resolution microfocus computed tomography (microCT) was used to quantitatively describe the microstructure of calcified aortic valve cusps in full 3D. As case study in our work, this quantitative analysis was applied to normal-flow low-gradient severe AS (NF-LG-SAS), for which the medical prognostic is still highly debated in the current literature, and high-gradient severe AS (HG-SAS). The volume proportion of calcification, the size and number of calcified particles and their density composition was quantified. A new size-based classification considering small-sized particles that are not detected with in vivo imaging was defined for macro-, meso- and microscale calcifications. Volume and thickness of aortic valve cusps, including the complete thickness distribution, were also determined. Moreover, changes in the cusp soft tissues were also visualized with microCT and confirmed by scanning electron microscopy images of the same sample. NF-LG-SAS cusps contained lower relative amount of calcifications than HG-SAS. Moreover, the number and size of calcified objects and the volume and thickness of the cusps were also lower in NF-LG-SAS cusps than in HG-SAS. The application of high-resolution ex vivo microCT to stenotic aortic valve cusps provided a quantitative description of the general structure of the cusps and of the calcifications present in the cusp soft tissues. This detailed description could help in the future to better understand the mechanisms of AS.

Pacing maneuvers from the aortic cusps: A useful technique during ablation of focal arrhythmias arising from the aortic root.

The ablation of arrhythmias arising near the His-bundle region in the non-coronary aortic cusp (NCAC) is challenging. Among the aortic sinuses of Valsalva, the NCAC is located between the right atrium and the left atrium. For this reason, pacing from the NCAC should result in atrial capture while pacing from the right and left coronary cusps (LCC) may result in ventricular capture. The objective of this study is to prove that atrial capture during pacing from the sinuses of Valsalva may be used to confirm a correct position in the non-coronary cusp. A total of 30 patients with structurally normal heart undergoing left sided ablation procedures, underwent electrophysiological study of the aortic cusps. Each of the aortic valve cusps was paced with increasing outputs and analyzed offline to determine their unique electrocardiographic characteristics. In the NCAC, we obtained an atrial capture in 29 out of 30 patients (96.6%). The atrial capture was highly specific for a position in the NCAC (p<.001). The median output required to capture from the cusp was 10mA (range 5-25mA) at a pulse width of 2ms. In the right coronary cusp (RCC) and LCC, we obtained ventricular capture in all patients (100%). The median output required to capture from the cusp was 10mA (range 10-25mA) in RCC and 25mA (range 10-25mA) in LCC at a pulse width of 2ms. Atrial capture during a pacemapping from the aortic cusps can be considered proof of a correct position in NCAC.

Veno-Pulmonary Arterial Extracorporeal Membrane Oxygenation in Severe Acute Respiratory Distress Syndrome: Should We Consider Mechanical Support of the Pulmonary Circulation From the Outset?

Veno-Pulmonary Arterial Extracorporeal Membrane Oxygenation in Severe Acute Respiratory Distress Syndrome: Should We Consider Mechanical Support of the Pulmonary Circulation From the Outset?