Alkhouli, M.A

Abstract Background Topological data analysis (TDA) is the state-of-the-art unsupervised machine learning framework that can provide insight into the dataset and visualize condensed information via the topological network graph. This robust approach was never used to assess the heterogeneous MitraClip population. Purpose We aim to develop a TDA model that will identify prognostically-distinct phenogroups in MitraClip patients without a priori knowledge of the population and their outcomes. Method Patients who underwent MitraClip (June 2014-September 2020) at Mayo Clinic sites were identified from the institutional database for baseline and follow-up data. Thirteen variables were used for TDA. The topological network graph was created using the Python Scikit-TDA Kepler-Mapper package (v. 2.0.1), and clustering was performed at the graph level with Louvain's modularity method. Kaplan-Meier survival analysis was used to assess the all-cause mortality endpoint of each cluster identified in an unsupervised manner. The dataset with cluster labels was also used to train a Light Gradient Boosted Machine model, and SHapley Additive exPlanations (SHAP) analysis was applied to determine the feature importance. Results A total of 389 consecutive patients were included in the final analysis and two major clusters consisting of 384 patients were identified. The mean age was 80.3±8.7 years; 256 (65.8%) were male. The mean Society of Thoracic Surgeons Mitral Valve Replacement risk score was 9.6±6.9%. Fifty-five (14.5%) patients died during the mean follow duration (185 days). Kaplan-Meier analysis showed significant survival differences among the two clusters (HR: 2.38; 95% CI: 1.39–4.06, p=0.001; Figure 1). Clusters 1 (n=195) was associated with > mild residual mitral regurgitation and worse survival performance and was characterized with worse tricuspid regurgitation severity, a higher proportion of patients with atrial fibrillation/flutter, anterior leaflet prolapse, and mitral annular/leaflet calcification, as summarized in Table 1. Conclusion TDA can identify distinct phenotype clusters with prognostic significance in MitraClip patients based on mitral valve morphology and clinical risk factors. This simple model can facilitate clinical risk stratification for MitraClip patients regarding procedural success and survival performance. Funding Acknowledgement Type of funding sources: None.

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction: Transesophageal echocardiography (TEE) has long provided excellent diagnostic imaging of left-sided valvular pathology with an excellent safety profile; however, recent data has suggested an increased risk of injury related to TEE guidance. Purpose This study aims to evaluate the incidence and nature of TEE-related oropharyngeal or esophageal complications in patients undergoing TEE-guided structural heart procedures and identify associated risk factors. Methods We reviewed consecutive patients undergoing TEE-guided structural heart procedures from 2005-2020. All procedures were performed under general anesthesia. TEE-related oropharyngeal or esophageal complications were defined as those occurring within 30 days of the procedure resulting in i) persistent dysphagia, odynophagia, or upper gastrointestinal bleeding requiring prolonged endotracheal intubation, therapeutic endoscopic or surgical intervention, or diagnostic imaging that demonstrated oropharyngeal or esophageal injury. ii) upper gastrointestinal bleed requiring transfusion, hemodynamic compromise warranting mechanical or pharmacologic support; or iii) oropharyngeal or esophageal complications leading to death. For multivariate analysis, all variables with a p < 0.15 at univariate analysis were included in the model. Results Among 1229 adult patients undergoing TEE-guided structural heart procedures between 2005-2020, 274 underwent a transcatheter aortic valve replacement (TAVR) with the remaining 955 undergoing either mitral valve transcatheter edge-to-edge repair (mTEER, n = 278), mitral paravalvular leak closure (PVLC, n = 354), mitral valve-in-valve replacement (VIV, n = 41), or left atrial appendage closure (LAAO, n = 282). Of these, 6 (0.5 %) had TEE-related complications; 0% TAVR, 0% VIV, 0.36% LAAO, 0.28% PVLC, 1.41% mTEER (p = 0.14). Of the six patients with complications 3 required at least one day of prolonged tracheal intubation and one a blood transfusion. None required surgical repair. Factors associated with increased complication risk (Table) included a prior history of gastrointestinal bleed (Odds ratio 5.44 [0.98-30.04; p = 0.05]) and longer procedural time (OR per 30 min 1.15 [1.01-1.31, p = 0.03]). Patients undergoing mTEER had an increased risk of complication (OR 6.76 [1.23-37.1 p = 0.03]) and longer procedural time (OR per 30 mins 1.15[1.01-1.31, p = 0.04]) compared to other all other procedures. Conclusion(s): In a large series of patients undergoing cardiac structural interventions under general anesthesia with TEE-guidance, rates of TEE-induced injury were low. Risk of oropharyngeal or esophageal complications was increased with longer procedure times, prior gastrointestinal bleeding history, increased age, increased pre-procedural creatinine, procedural type being mTEER and in male patients, lower height. Abstract Table

Abstract Background There is a paucity of data about the prevalence and natural history of mitral annular calcification (MAC). Purposes In a large cohort of patients undergoing clinically-indicated echocardiography, we aimed to evaluate the prevalence and the natural history of MAC, and the frequency of associated mitral valve dysfunction (MVD). Methods Retrospective review of all patients who underwent echocardiographic evaluation at our institution between January 1st and December 31st 2015. The patients were stratified into 3 groups: MAC with MVD, MAC without MVD, no MAC. MVD was defined as moderate or greater mitral regurgitation (MR) or stenosis (MS). The 3 groups were compared for baseline clinical and echocardiographic characteristics and all-cause mortality during follow-up. Results Of 24,415 evaluated patients, 5478 (22%) had MAC. Patients with MAC were older (75±10 vs. 60±16 years, p<0.01) and more often female (46% vs. 43%, p<0.01). MVD was more frequently observed in patients with MAC (16% vs. 7%, p<0.01); moderate or greater MR was found in 10% of patients with MAC vs. 6% without MAC (p<0.01) and MS in 7% vs. 0.5% (p<0.01). In patients with MAC, those with MVD were more often female and more frequently had creatinine ≥2mg/dl and moderate or greater aortic stenosis (AS) than those without MVD (Fig. A). Kaplan-Meier survivals at 1 year were 75% in patients with MAC and MVD, 87% in those with MAC without MVD, and 92% in those without MAC (Fig B). Adjusted for age, sex, diabetes, creatinine ≥2 mg/dl, coronary artery disease, left ventricular ejection fraction <50%, and AS, MAC was associated with higher all-cause mortality (adjusted hazard ratio1.4, 95% confidence interval: 1.3–1.5, p<0.01); combined MAC and MVD was associated with the highest mortality during follow-up of 2.5±1.8 years. Conclusion In a large cohort of patients undergoing echocardiographic evaluation, the prevalence of MAC was 22%. MV dysfunction was more than twice as prevalent in patients with MAC as without. Patients with MAC had higher all-cause mortality than patients without MAC. Among patients with MAC and mitral valvular dysfunction, adjusted mortality was two-fold higher compared to those without MAC. Funding Acknowledgement Type of funding source: None