Infodemics: Use of Peer Reviewed and Non-Peer Reviewed Information by Post Grad-uate Trainee Doctors for COVID-19 Pandemic in Pakistan

Background: Reliable and peer reviewed information is of immense importance for preventive, diagnostic and curative solutions and efforts should be done to minimize inaccurate infodemics among post graduate trainee doctors. Objective: The aim of the study was to access the use of Peer Reviewed and Non-Peer Reviewed Information by post graduate trainee doctors for COVID-19 Pandemic in Pakistan. Methods: The study was analytical cross sectional in design and was conducted in 3193 post graduate trainee doctors employing Electronic Logbook (elog) system of College of Physicians and Surgeons, Pakistan. An online survey included demographic characteristics, year of training, specialty and sources of information used for COVID-19 pandemic. Results: Total 3193 study participants from all provinces of Pakistan were included with mean age of 28.68 years. Majority of participants (58.66%) used both peer reviewed and non-peer reviewed information source for getting updated guidelines and information about COVID-19. According to bivariate analysis results, significant differences were revealed between the source of information and the age (p < 0.001), province (p < 0.001) and gender (p < 0.002). Multivariate logistic regression results showed that the age less than 30 years (AOR = 1.311, 95% (CI: 0.800, 2.146), working in Khyber Pakhtunkhwa province (AOR = 1.549, 95% (CI: 1.210-1.982) and female gender(AOR = 1.551, 95% (CI: 1.303, 1.847). was significantly associated with increased use of social media for getting information. Conclusion: Use of non-peer reviewed information for COVID-19 pandemic by postgraduate trainee doctors is common.

Healthcare strategies and initiatives about COVID19 in Pakistan: Telemedicine a way to look forward

The COVID-19 pandemic is one of the unprecedented devastating catastrophes with severe public health threat globally. Low and middle income countries (LMICs) are trying hard to cope with the rapidly changing global scenario and trying to mitigate this double crisis of pandemic and economic recession. This pandemic, has led to major changes in global and regional health care delivery proceedings with surge in telemedicine to provide the required services and also giving priority to control the disease spread.

Role of digital health in improving physical and mental well-being during COVID-19 pandemic

Introduction

Due to the COVID-19 pandemic, there is a steep rise in the acceptance of telemedicine and digital health, including increased interest in pursuing mental health treatment through telepsychiatry. Digital health helps following social distancing measures and increases the health outcomes.

Objectives

To see the role of digital health in improving physical and mental well-being during COVID-19 Pandemic

Methods

This study is a part of a large global project where 240 people inquired advice on phone app during COVID-19-Pandemic. Later on, a short study was conducted on the same population through survey to evaluate the effectiveness of digital health/tele-mental health. We also searched PubMed, Google Scholar, PsychInfo, and Medline for words “Digital Health, Tele-mental health, COVID-19-Pandemic”. Reviewed 40 articles and included 3 in this review1,4,5.

Results

We received a total of 98 responses. 65.6% people reported that online health resources are helpful in relieving pandemic-induced anxiety/stress, 66.2% reported to continue online health services after pandemic, 37.7% noted that digital health saves times in waiting areas, 46% reported lack of physical interaction with doctor as a disadvantage of digital health, and 40.3% reported comfort in using tele-mental health. Our literature review has shown barriers like privacy concerns and technological issues1. Provision of tele-psychiatry is safe and effective in continuity of mental health care.4,5

Conclusions

There has been an increased inclination towards digital health during any disaster. During COVID-19-Pandemic, digital health has increased access to mental health care and reduced risk of infection. The drawbacks include poor patient-doctor relationship, reimbursement concerns, and lack of confidentiality.

Highly Potent and Selective Ectonucleoside Triphosphate Diphosphohydrolase (ENTPDase1, 2, 3 and 8) Inhibitors Having 2-substituted-7- trifluoromethyl-thiadiazolopyrimidones Scaffold

BACKGROUND

The ecto-nucleoside triphosphate diphosphohydrolases (NTPDases) terminate nucleotide signaling via the hydrolysis of extracellular nucleoside-5'-triphosphate and nucleoside- 5'-diphosphate, to nucleoside-5'-monophosphate and composed of eight Ca2+/Mg2+ dependent ectonucleotidases (NTPDase1-8). Extracellular nucleotides are involved in a variety of physiological mechanisms. However, they are rapidly inactivated by ectonucleotidases that are involved in the sequential removal of phosphate group from nucleotides with the release of inorganic phosphate and their respective nucleoside. Ectonucleoside triphosphate diphosphohydrolases (NTPDases) represent the key enzymes responsible for nucleotides hydrolysis and their overexpression has been related to certain pathological conditions. Therefore, the inhibitors of NTPDases are of particular importance in order to investigate their potential to treat various diseases e.g., cancer, ischemia and other disorders of the cardiovascular and immune system.

METHODS

Keeping in view the importance of NTPDase inhibitors, a series of thiadiazolopyrimidones were evaluated for their potential inhibitory activity towards NTPDases by the malachite green assay.

RESULTS

The results suggested that some of the compounds were found as non-selective inhibitors of isozyme of NTPDases, however, most of the compounds act as potent and selective inhibitors. In case of substituted amino derivatives (4c-m), the compounds 4m (IC50 = 1.13 ± 0.09 μM) and 4g (IC50 = 1.72 ± 0.08 μM) were found to be the most potent inhibitors of h-NTPDase1 and 2, respectively. Whereas, compound 4d showed the best inhibitory potential for both h-NTPDase3 (IC50 = 1.25 ± 0.06 μM) and h-NTPDase8 (0.21 ± 0.02 μM). Among 5a-t derivatives, compounds 5e (IC50 = 2.52 ± 0.15 μM), 5p (IC50 = 3.17 ± 0.05 μM), 5n (IC50 = 1.22 ± 0.06 μM) and 5b (IC50 = 0.35 ± 0.001 μM) were found to be the most potent inhibitors of h-NTPDase1, 2, 3 and 8, respectively. Interestingly, the inhibitory concentration values of above-mentioned inhibitors were several folds greater than suramin, a reference control. In order to determine the binding interactions, molecular docking studies of the most potent inhibitors were conducted into the homology models of NTPDases and the putative binding analysis further confirmed that selective and potent compounds bind deep inside the active pocket of the respective enzymes.

CONCLUSION

The docking analysis proposed that the inhibitory activity correlates with the hydrogen bonds inside the binding pocket. Thus, these derivatives are of interest and may further be investigated for their importance in medicinal chemistry.

The Effect of COVID-19 Pandemic on Performance of Postgraduate Medical Trainee Doctors: A Nationwide Epidemiological Study in Pakistan

OBJECTIVE

To find out various organizational, personal, and systemic factors influencing the performance of the postgraduate trainee doctors in managing COVID-19 pandemic.

STUDY DESIGN

Analytical cross-sectional study.

PLACE AND DURATION OF STUDY

Conducted in various medical institutions of Pakistan from 15th  April to 30th  June, 2020.

METHODOLOGY

An analytical cross-sectional study was conducted on 11,656 postgraduate doctors. They were contacted through the e-log system of College of Physicians and Surgeons Pakistan. Semi-structured questionnaire was used consisting of demographic details, presenting symptoms, systemic involvements, clinical features, diagnostic tests, management of cases, authenticity of the  information used, telemedicine services, practice of preventive measures, training and interactive educational activities, performance-based tasks and details about workplace environment. Mean and standard deviation was reported for continuous variables. Bivariate and multivariate analyses were used to report p values.

RESULTS

Among 11,656 postgraduate doctors, 3,193 (27.4%) were directly involved in the management of COVID-19 patients in designated special corona facilities. Multivariate analysis was performed to control confounders. The risk factors, found statistically significant with performance, were presence of comorbidity (OR 1.261; 95% C.I.1.06-1.50), allergic and autoimmune disorders (OR 1.18; 95% C.I.1.03-1.35), confirmed COVID-19 status due to exposure (OR 0.570; 95% C.I.0.41-0.81), and care provision to old parents (OR 1.299; 95% C.I.1.19-1.42).

CONCLUSION

The effect of COVID-19 on performance of postgraduate doctors was multi-factorial. Significant risk factors were presence of a comorbidity, allergic and autoimmune disorders, and confirmed COVID-19 due to exposure. Key Words: COVID 19, Postgraduate trainee, Pandemic, Comorbidity, PCR.

Functionalized Oxoindolin Hydrazine Carbothioamide Derivatives as Highly Potent Inhibitors of Nucleoside Triphosphate Diphosphohydrolases

Ectonucleoside triphosphate diphosphohydrolases (NTPDases) are ectoenzymes that play an important role in the hydrolysis of nucleoside triphosphate and diphosphate to nucleoside monophosphate. NTPDase1, -2, -3 and -8 are the membrane bound members of this enzyme family that are responsible for regulating the levels of nucleotides in extracellular environment. However, the pathophysiological functions of these enzymes are not fully understood due to lack of potent and selective NTPDase inhibitors. Herein, a series of oxoindolin hydrazine carbothioamide derivatives is synthesized and screened for NTPDase inhibitory activity. Four compounds were identified as selective inhibitors of h-NTPDase1 having IC₅₀ values in lower micromolar range, these include compounds 8b (IC₅₀ = 0.29 ± 0.02 µM), 8e (IC₅₀ = 0.15 ± 0.009 µM), 8f (IC₅₀ = 0.24 ± 0.01 µM) and 8l (IC₅₀ = 0.30 ± 0.03 µM). Similarly, compound 8k (IC₅₀ = 0.16 ± 0.01 µM) was found to be a selective h-NTPDase2 inhibitor. In case of h-NTPDase3, most potent inhibitors were compounds 8c (IC₅₀ = 0.19 ± 0.02 µM) and 8m (IC₅₀ = 0.38 ± 0.03 µM). Since NTPDase3 has been reported to be associated with the regulation of insulin secretion, we evaluated our synthesized NTPDase3 inhibitors for their ability to stimulate insulin secretion in isolated mice islets. Promising results were obtained showing that compound 8m potently stimulated insulin secretion without affecting the NTPDase3 gene expression. Molecular docking studies of the most potent compounds were also carried out to rationalize binding site interactions. Hence, these compounds are useful tools to study the role of NTPDase3 in insulin secretion.

Stroke after transcatheter aortic valve implantation: new insights into risk prediction

Background

Stroke is still a feared complication following transcatheter aortic valve implantation (TAVI), associated with increased mortality and severe impact on patients' daily living. Despite technological development and knowledge improvement, cerebrovascular events (CVE) are still not predictable so far and simple risk scores are lacking.

Purpose

This study aimed to evaluate different preprocedural factors that may favour stroke after TAVI, especially regarding severity of aortic calcification.

Methods

From May 2011 to January 2018 a total of 1365 patients underwent TAVI with a balloon-expandable (n=442, 32.4%) or self-expandable (n=923, 67.6%) device at our institution. All patients underwent multi-slice computed tomography (MSCT) before TAVI. To obtain the significant factors for stroke risk prediction we performed multivariate regression analysis and selected the optimal cut-off values according to the maximum Youden index for dichotomization of the risk score items. Finally, we used receiver operating characteristics (ROC) analysis and areas under the ROC curves (AUC) to validate our risk score in comparison to other existing models.

Results

60 of 1365 patients (4.4%) had new neurological impairment after TAVI during hospital stay (mean 11.2±6.7 days). We performed propensity score matching (1:10) to balance baseline characteristics between patients with and without stroke following TAVI, resulting in 56 patients with in-hospital stroke and 521 patients without. Preprocedural factors associated with stroke turned out to be history of prior stroke (OR 1.94; 95% CI 0.85–4.43; p=0.114), aortic valve area ≥0.545 cm2 (OR 3.11; 95% CI 1.16–8.34; p=0.024), atrioventricular angle ≥48.5° (OR 2.32; 95% CI 1.20–4.49; p=0.013), RCC Agatston Score ≥447.2 AU (OR 1.8; 95% CI 0.94–3.44; p=0.077), LVOT Agatston Score ≥262.4 AU (OR 2.01; 95% CI 1.08–3.75; p=0.028) and ascending thoracic aorta Agatston Score ≥116.4 AU (OR 2.21; 95% CI 1.17–4.17; p=0.015). ROC analysis showed that our risk model had an AUC of 0.73 (95% CI 0.66–0.80; p&lt;0.001), a sensitivity of 70.6%, a specificity of 69.0%, a positive predictive value of 19.5% and a high negative predictive value of 95.7%. Our risk model appeared to be the best for stroke prediction after TAVI compared to other risk scores used in literature before like EuroSCORE II (AUC 0.50; 95% CI 0.43–0.58; p=0.950) or CHA2DS2-VASc Score (AUC 0.62; 95% CI 0.55–0.70; p=0.004).

Conclusion

Especially aortic root calcium volume assessed by MSCT predicts CVE after TAVI and could be integrated into a six items risk model for preprocedural prediction of stroke after TAVI. This model could guide us in identifying those patients who are most likely to benefit from transcatheter cerebral embolic protection devices.

Funding Acknowledgement

Type of funding source: None

Use and success evaluation of percutaneous aortic balloon valvuloplasty in different hemodynamic entities of severe aortic stenosis in the TAVR era

Background

In the era of transcatheter aortic valve replacement (TAVR), there is renewed interest in percutaneous balloon aortic valvuloplasty (BAV), which may qualify as the primary treatment option of choice in special clinical situations. Success of BAV is commonly defined as a significant mean pressure gradient reduction after the procedure.

Purpose

To evaluate the correlation of the mean pressure gradient reduction and increase in the aortic valve area (AVA) in different flow and gradient patterns of severe aortic stenosis (AS).

Methods

Consecutive patients from 01/2010 to 03/2018 undergoing BAV were divided into normal-flow high-gradient (NFHG), low-flow low-gradient (LFLG) and paradoxical low-flow low-gradient (pLFLG) AS. Baseline characteristics, hemodynamic and clinical information were collected and compared. Additionally, the clinical pathway of patients (BAV as a stand-alone procedure or BAV as a bridge to aortic valve replacement) was followed-up.

Results

One-hundred-fifty-six patients were grouped into NFHG (n=68, 43.5%), LFLG (n=68, 43.5%) and pLFLG (n=20, 12.8%) AS. Underlying reasons for BAV and not TAVR/SAVR as the primary treatment option are displayed in Figure 1. Spearman correlation revealed that the mean pressure gradient reduction had a moderate correlation with the increase in the AVA in patients with NFHG AS (r: 0.529, p&lt;0.001) but showed no association in patients with LFLG (r: 0.145, p=0.239) and pLFLG (r: 0.030, p=0.889) AS. Underlying reasons for patients to undergo BAV and not TAVR/SAVR varied between groups, however cardiogenic shock or refractory heart failure (overall 46.8%) were the most common ones. After the procedure, independent of the hemodynamic AS entity, patients showed a functional improvement, represented by substantially lower NYHA class levels (p&lt;0.001), lower NT-pro BNP levels (p=0.003) and a numerical but non-significant improvement in other echocardiographic parameters like the left ventricular ejection fraction (p=0.163) and tricuspid annular plane systolic excursion (TAPSE, p=0.066). An unplanned cardiac re-admission due to heart failure was necessary in 23.7% patients. Less than half of the patients (44.2%) received BAV as a bridge to TAVR/SAVR (median time to bridge 64 days). Survival was significantly increased in patients having BAV as a staged procedure (log-rank p&lt;0.001).

Conclusion

In daily clinical practice, the mean pressure gradient reduction might be an adequate surrogate of BAV success in patients with NFHG AS but is not suitable for patients with other hemodynamic entities of AS. In those patients, TTE should be directly performed in the catheter laboratory to correctly assess the increase of the AVA. BAV as a staged procedure in selected clinical scenarios increases survival and is a considerable option in all flow states of severe AS. (NCT04053192)

Figure 1

Funding Acknowledgement

Type of funding source: None

Performance of the Corevalve Evolut R and PRO in severely calcified anatomies: a propensity-score matched analysis

Background

The Corevalve Evolut R and PRO belong to the newer generation of self-expandable valves and are increasingly used to treat patients with severe aortic stenosis. Over the years, technical advancements and increasing experience with the procedure itself are responsible for excellent clinical and hemodynamic results. Patients with severely calcified native aortic valve anatomies still pose a special task to the implanting team since the risk for intraprocedural complications might be increased.

Purpose

To evaluate the hemodynamic and clinical performance of the CoreValve Evolut R and PRO in patients with severely calcified native aortic valve anatomies.

Methods

Baseline characteristics, imaging data and procedural outcome of patients undergoing transfemoral transcatheter aortic valve implantation with the CoreValve Evolut R and PRO from 09/2015 to 03/2018 were prospectively collected. Patients underwent high-resolution multisclice computed tomography (MSCT). A pre-specific threshold of 600 Hounsfield units was set to account for the hyperdensity of the applied contrast medium and to enable comparability with MSCT thresholds, derived by non-contrast enhanced MSCT scans. Patients were divided by the extent of calcification into a severely calcified anatomy group (men &gt;2062AU, woman &gt;1377AU) or a not severely calcified anatomy group (men &lt;2062AU, woman &lt;1377AU). Propensity score matching with the variables log EuroSCORE, LVOT calcium load and the cover index in a 1:2 fashion was performed and clinical and hemodynamic results in accordance with VARC II were collected.

Results

Ninety-eight patients with severely calcified anatomies (SC) could be identified and were matched with 196 patients with lower calcified (LC) anatomies. Patients with severely calcified anatomies were older (SC: 83.1 years vs. LC: 80.3 years, p&lt;0.001) and had a smaller aortic valve area (SC: 0.63cm2 vs. LC: 0.70cm2, p=0.028). The mean implantation depth did not differ (SC 5.4mm±2.4 vs. LC: 5.1±2.2, p=0.554). Pre-dilatation was more often performed in the SC group (SC: 30.6% vs. LC: 15.8%, p=0.003) and the stroke/TIA rate did not differ (SC: 5.1% vs. LC: 3.5%, p=0.532). In SC patients, a permanent pacemaker implantation was significantly more often needed (SC: 28.5% vs. LC:7.6%, p&lt;0.001). The mean pressure gradient after the procedure was effectively reduced (SC: 7.1mmHg±3.9 vs. LC: 7.8±3.7mmHg, p=0.477). No aortic regurgitation (AR) was more often present in patients with SC anatomies (SC: 72.5% vs. LC: 85.2%, p=0.011). The aortic regurgitation index numerically differed between groups without reaching statistical significance (SC: 24.1±7.1 vs. LC: 27.3±6.7, p=0.067).

Conclusion

The CoreValve Evolut R and PRO show a good clinical safety profile and excellent hemodynamic results even in patients with severely calcified anatomies. In those patients, a permanent pacemaker implantation was more often necessary.

Funding Acknowledgement

Type of funding source: None

Loeffler's Endocarditis and the Diagnostic Utility of Multimodality Imaging

Loeffler’s endocarditis is a rare form of restrictive cardiomyopathy associated with eosinophilia and endomyocardial fibrosis. It manifests most commonly as diastolic dysfunction or valvular abnormalities due to eosinophilic infiltration and degranulation. Herein, we chronicle a case of left ventricular involvement with Loeffler’s endocarditis. We emphasize the utility of multimodality imaging including two-dimensional echocardiography and cardiac magnetic resonance imaging in providing diagnostic information, as there is no standardized diagnostic criteria to date.

Efficient Nuclease-Directed Integration of Lentivirus Vectors into the Human Ribosomal DNA Locus

Lentivirus vectors (LVs) are efficient tools for gene transfer, but the non-specific nature of transgene integration by the viral integration machinery carries an inherent risk for genotoxicity. We modified the integration machinery of LVs and harnessed the cellular DNA double-strand break repair machinery to integrate transgenes into ribosomal DNA, a promising genomic safe-harbor site for transgenes. LVs carrying modified I-PpoI-derived homing endonuclease proteins were characterized in detail, and we found that at least 21% of all integration sites localized to ribosomal DNA when LV transduction was coupled to target DNA cleavage. In addition to the primary sequence recognized by the endonuclease, integration was also enriched in chromatin domains topologically associated with nucleoli, which contain the targeted ribosome RNA genes. Targeting of this highly repetitive region for integration was not associated with detectable DNA deletions or negative impacts on cell health in transduced primary human T cells. The modified LVs characterized here have an overall lower risk for insertional mutagenesis than regular LVs and can thus improve the safety of gene and cellular therapy.

VSeq-Toolkit: Comprehensive Computational Analysis of Viral Vectors in Gene Therapy

Viral vector characterization and analysis are important components for the development of safe gene therapeutic products, elucidating the potential genotoxic and immunogenic effects of vectors and establishing their safety profiles. Here, we present VSeq-Toolkit, which offers varying analysis modes for viral gene therapy data. The first mode determines the undesirable known contaminants and their frequency in viral preparations or other sequencing data. The second mode is designed for the analysis of intra-vector fusion breakpoints and the third mode for unraveling the viral-host fusion events distribution. Analysis modes of our toolkit can be executed independently or together and allow the analysis of multiple viral vectors concurrently. It has been designed and evaluated for the analysis of short read high-throughput sequencing data, including whole-genome or targeted sequencing. VSeq-Toolkit is developed in Perl and Bash programming languages and is available at https://github.com/CompMeth/VSeq-Toolkit.

Epidemiology of viral hepatitis B and C in Punjab, Pakistan: a multicenter cross-sectional study, 2017-18

Background: Globally, approximately 240 million people are chronically infected with hepatitis B virus (HBV) and hepatitis C virus (HCV), which are responsible for 96% of all hepatitis-related mortality. Pakistan has the second highest prevalence of HCV in the world. Methods: We conducted this study to ascertain the prevalence and potential risk factors associated with HBV and HCV infections in Punjab. A multi-center cross-sectional study was conducted, involving 24 Hepatitis Prevention and Treatment Clinics of the Pakistan Kidney and Liver Institute and Research Center clinics, Lahore. A total of 141,705 individuals who visited the clinics during 2017-18 were included for seroprevalence analysis of hepatitis B (HBsAg) and C (Anti-HCV). In addition, 12,427 individuals from the main group underwent detailed face-to-face interviews based on a predesigned questionnaire for risk factor assessment. Results: The overall prevalence for HBV and HCV was 8.4% and 42.7%, respectively. Of those with HCV infection, 4.2% had a co-infection. The transgender population had a higher seroprevalence of HBV (11.8%) and HCV (58.8%). Higher HBV seroprevalence was found in a younger age group (16-30 years), while the older age group (>61 years) had a higher HCV seroprevalence. Geographically, Muzaffargarh district had the highest HBV seroprevalence at 26%, followed by Rajanpur district (20.3%). HCV seroprevalence was significantly (P value <0.05) higher in Shujabad district (66.4%), followed by Muzaffargarh (65.2%). Using multivariable logistic regression analysis, age, gender, intravenous injections, hijama therapy, dental procedure, circumcision by barbers, barber shaving, hospitalization and having had surgical procedures were all found to be significant risk factors (OR >1; p<0.05) for HBV and HCV. Conclusions: There is an urgent need for proper implementation of preventive and control strategies, as well as formal evaluation and monitoring mechanisms. Sustainable and adequate funding of public-sector hepatitis programs is also an extremely important area that should not be neglected.

P3742Transcatheter aortic valve implantation in large annuli: incidence and predictors of specific adverse events with the largest self-expanding device

Background

The recently released largest self-expanding transcatheter aortic valve device (STHV-34) is characterized by good results but nevertheless demands an experienced team for the implantation in large annuli.

Purpose

Looking at multi slice computed tomography (MSCT) and procedural data, we tried to identify characteristics that could explain intraprocedural VARC-2 and valve specific non-VARC-2 events.

Methods

We performed a single center retrospective analysis in 80 patients treated with STHV-34. STHV-34 patients were separated into subjects without events (NE, n=43, 54%) and the following adverse events: resheathing/-capture processes (RS/C, n=19, 24%), valve dislodgments (VD, n=21; 26%), infolding (IF, n=6, 8%) and complete dislocation with bail-out valve-in-valve implantation (ViV, n=3, 4%). Events were further categorized in non-VARC-2 and VARC-2. The analysis sought for underlying anatomical conditions and defined risk factors by multivariate analysis.

Results

Primary device success was reached in 96% and immediate postprocedural absence of moderate-to-severe aortic regurgitation was 100%. We identified specific anatomical conditions predisposing for non-VARC-2 and VARC-2 events: RS/C: annular calcium load<1600 AU (OR 47 [CI 1.4–216], p=0.0004). IF: peripheral kinking (RR 5.0 [CI 1.0–24], p=0.0478) and previous RS/C maneuvers (83%). ViV: annular ellipticity index (NS 1.2±0.1 vs. ViV 1.4±0.1, p=0.0049), aortic angulation (AA) angle (NS 54.0±7.0° vs. ViV 61.7±1.5°, p=0.0240) and LVOT-AO angle (NS 149.1±18.9° vs. ViV 130.3±3.5°, p=0.0470).

Conclusion

We confirm high procedural success for the largest currently available STHV-34. The incidence of intraprocedural non-VARC-2 and VARC-2 events are associated with anatomical characteristics that may influence valve selection and implantation strategy.

P5583Micro-movement during transcatheter aortic valve implantation with a contemporary self-expandable prosthesis

Background

Precise positioning of the prosthesis is a crucial step during transcatheter aortic valve implantation. In some cases, contemporary self-expandable prostheses show micro-movement (MM) during the final phase of release.

Purpose

We aimed to establish a definition for MM, evaluated the incidence of MM using the CoreValve Evolut RTM, investigated potential risk factors for MM and the associated clinical outcomes.

Methods

MM was defined as movement of the prosthesis of at least 1.5 mm from its position directly before release compared to its final position. Patients were grouped according to the occurrence (+MM) or absence (-MM) of MM. Baseline characteristics, imaging data and outcome parameters in accordance with the updated valve academic research consortium (VARC-2) criteria were retrospectively analyzed.

Results

We identified 258 eligible patients. MM occurred in 31.8% (n=82) of cases with a mean magnitude of 2.8±2.2 mm in relation to the left coronary cusp and 3.0±2.1 mm to the non-coronary cusp. Clinical and hemodynamic outcomes were similar in both groups. The mean pressure gradient was effectively reduced after TAVI (-MM vs. +MM: 7±3.4 mmHg vs. 8±3.9 mmHg, p=0.326) with consistency over a follow-up period of at least three months (-MM vs. +MM: 6.7±3.7 mmHg vs. 7.9±8.4 mmHg, p=0.168). At three months follow-up most of the patients presented with no aortic regurgitation (-MM vs. +MM: 64% vs. 67.9%, p=0.569). Mild aortic regurgitation was observed in 34.2% of the -MM group and in 29.5% of the +MD group (p=0.414). Moderate aortic regurgitation occurred in 1.9% of all patients with no differences between groups (-MM vs. +MM: 1.9% vs. 2.6%, p=0.662). Patients with MM presented with a more symmetric calcification pattern (-MM vs. +MM: 27.3% vs. 40.2%; p=0.037) and a larger aortic valve area (-MM vs. +MM: 0.6 cm2 ± 0.3 vs. 0.7 cm2 ± 0.2; p=0.014), which was found to be a potential risk factor for the occurrence of MM in a multivariate regression analysis (OR 3.5; 95% CI: 1.1–10.9; p=0.032)

Conclusion

MM occurred in nearly one third of patients and did not affect clinical and hemodynamic outcome. A larger aortic valve area was the only independent risk factor for the occurrence of MM.

P2467Fusion imaging (Anatomical Intelligence) enables automated left atrial appendage sizing in real-time a single center pilot study

Background and purpose

Percutaneous left atrial appendage occlusion (LAAO) depicts an alternative treatment for patients with atrial fibrillation who are deemed for long-term oral anticoagulation therapy. In order to perform a successful LAAO accurate sizing of left atrial appendage (ostium, landing zone and depth) for device selection is essential. Echo-Fluoro fusion imaging in real-time offers with its latest prototype a patient-specific segmented automated 3D heart model and sizing of left atrial appendage (LAA). We therefore aimed to evaluate the automated segmented LAA sizing by comparing to 2D transesophageal (TOE) and MSCT measurements as gold standard.

Methods

We studied prospectively data of 8 consecutive patients who were admitted to our clinic for left atrial appendage closure. MSCT was performed preprocedural and analyzed with commercially available 3mensio software (Pie medical imaging). 2D TOE measurements and automated segmentation of the LAA and sizing were performed during the procedure by a highly experienced team of periinterventional cardiac imaging specialist and structural heart disease interventionalist who were blinded to the prior MSCT analysis. Dimension of ostium, landing zone (10 mm into the LAA parallel to the ostial plane at the level of the left circumflex for Amplatzer device) and depth (perpendicular to the ostial plane) were obtained in different TOE views according to instructions for use of Amulet Occluder. In order to generate an automated 3 D heart model, a high-quality 3D TOE image of the LAA volume and surrounding structures was acquired. After successful ECG-gated segmentation a 3 D heart model was generated. Automated LAA sizing followed in real-time. All measurements were taken into consideration before device selection. A Kruskal Wallis test was used to compare mean ranks of independent samples. A concordance analysis according to Kendall W was carried out to investigate reliability.

Results

The mean age of the patients was 82,6±4.15 years and half of the patients were female. All procedures were conducted successfully. The mean values of ostium and landing zone were comparable in TOE, automated sizing and MSCT sizing (ostium: 23,78±2,15 mm vs 25,71±5,25 mm vs 27,35±3,3 mm; (p=0,175); landing zone 22,13±3,18 mm vs 23,57±3,31 mm vs 24,00±3,51 mm; (p=0,377)). Furthermore, a significant concordance between the measurements was shown (ostium W= 0,991; p=0.045, landing zone W=0,835, p=0.014).

Conclusion

Automated LAA sizing acquired by fusion imaging may be an elegant real-time alternative for precise LAA Occluder device selection and needs to be investigated further.

P2274Single-center experience with different regimes of antiplatelet therapy and oral anticoagulation in transcatheter aortic valve replacement

Background

Antithrombotic therapy in transcatheter aortic valve replacement (TAVR) is highly controversial. Dual antiplatelet therapy (DAPT) for 3–6 months with aspirin and clopidogrel is the current recommendation. Whereas in patients with indication for OAC several regimes were described, ranging from OAC monotherapy to dual and even triple therapy. Besides vitamin K antagonists (VKA), non-Vitamin K oral anticoagulants (NOAC) are frequently used in TAVR patients with indication for permanent OAC.

Purpose

We therefore aimed to evaluated different antithrombotic regimes and their impact on outcome.

Methods

We performed a single center retrospective analysis in 1160 patients treated by transfemoral approach (TF TAVR). Primary endpoints were 30-day mortality, stroke and bleeding according to VARC-2 criteria. Secondary endpoint was all-cause mortality at 1 year.

Results

In 1160 patients with TF TAVR, a broad range of regimes occurred in clinical practice. The majority of patients were on DAPT (637 patients, 55.0%), followed by VKA + clopidogrel (186 patients, 16%). Other patients received OAC mono (98 patients; 9%), triple therapy (93 patients; 8%), NOAC mono (31 patients; 3%), single antiplatelet therapy (SAPT, 40 patients; 4%) or NOAC + clopidogrel (31 patients, 3%).

All-cause mortality 30 days after TF TAVR differed between the regimens. (SAPT/OAC+SAPT/N-OAC+DAPT 0.0% vs DAPT 3.6% vs OAC 10.2% vs. NOAC 1.3% vs NOAC+SAPT 0.3%; pANOVA<0.0001). Severe bleeding events were comparable (SAPT 5.0% vs DAPT 2.4% vs OAC 7.1% vs NOAC 1.3% vs OAC+SAPT 3.2% vs NOAC+SAPT 0.0% vs. N-OAC+SDPT 4.3%; pANOVA=0.15). Stroke rates were comparable in all subcohorts as well (SAPT 5.0% vs DAPT 3.0% vs OAC 7.1% vs NOAC 2.7% vs OAC+SAPT 1.6% vs NOAC+SAPT 0.0% vs. N-OAC+DAPT 1.1%; pANOVA=0.13). Only 2 hemorrhagic strokes (5.6%) appeared under DAPT and OAC mono respectively, whereas all others were of thromboembolic origin (94.4%). Surprisingly, all-cause mortality at one-year after TF TAVR was higher in OAC patients compared to all other used regimes (logrankoverallp=0.0012).

Conclusion

Data from our retrospective analysis indicate that a variety of different antithrombotic regimes occur even in a single centre analysis. All-cause mortality was enhanced in patients with oral anticoagulation. Therefore, clinical trials need to investigate if this is only explained by additional atrial fibrillation.