Management of Systemic Inflammatory Response Syndrome after Cardiovascular Interventions. Diagnostic, Prognostic and Therapeutic Implications

A substantial number of patients may experience a systemic inflammatory response syndrome (SIRS) and related adverse events after transcatheter aortic valve implantation and endovascular aortic aneurysm repair. Although a clear etiology has not been established, endothelial disruption and tissue-ischemic response secondary to the foreign material may represent the trigger events. A latency period (0-48 hours) may occur between the initial injury and onset of symptoms mirroring an initial local response followed by a systemic response. Clinical presentation can be mild or severe depending on external triggers and patient's characteristics. Diagnosis is challenging because it simulates an infection, but lack of response to antibiotics, negative cultures are supportive of SIRS. Increased in-hospital stay, readmissions, major cardiovascular events, and reduced durability of the device used are the main complications. Treatment includes non-steroidal anti-inflammatory drugs or corticosteroids. In conclusion, further studies are warranted to fully explore pathophysiologic mechanisms underpinning SIRS as well as the possibility to enhance device material immune compatibility in order to reduce the host tissue's inflammatory reaction.

Mental illness and cardiovascular health: observational and polygenic score analyses in a population-based cohort study

BACKGROUND

Individuals with serious mental illness have a markedly shorter life expectancy. A major contributor to premature death is cardiovascular disease (CVD). We investigated associations of (genetic liability for) depressive disorder, bipolar disorder and schizophrenia with a range of CVD traits and examined to what degree these were driven by important confounders.

METHODS

We included participants of the Dutch Lifelines cohort (N = 147 337) with information on self-reported lifetime diagnosis of depressive disorder, bipolar disorder, or schizophrenia and CVD traits. Employing linear mixed-effects models, we examined associations between mental illness diagnoses and CVD, correcting for psychotropic medication, demographic and lifestyle factors. In a subsample (N = 73 965), we repeated these analyses using polygenic scores (PGSs) for the three mental illnesses.

RESULTS

There was strong evidence that depressive disorder diagnosis is associated with increased arrhythmia and atherosclerosis risk and lower heart rate variability, even after confounder adjustment. Positive associations were also found for the depression PGSs with arrhythmia and atherosclerosis. Bipolar disorder was associated with a higher risk of nearly all CVD traits, though most diminished after adjustment. The bipolar disorder PGSs did not show any associations. While the schizophrenia PGSs was associated with increased arrhythmia risk and lower heart rate variability, schizophrenia diagnosis was not. All mental illness diagnoses were associated with lower blood pressure and a lower risk of hypertension.

CONCLUSIONS

Our study shows widespread associations of (genetic liability to) mental illness (primarily depressive disorder) with CVD, even after confounder adjustment. Future research should focus on clarifying potential causal pathways between mental illness and CVD.

Determinants of Mortality and Mid-Term Outcomes After Transcarotid Artery Revascularization and Transfemoral Carotid Artery Stenting

OBJECTIVES

The potential benefit of transcarotid artery revascularization (TCAR) over transfemoral carotid artery stenting (tfCAS) has been studied in the perioperative period with lower rates of stroke and death; however, data on mid-term outcomes are limited. We aimed to evaluate 3-year outcomes after TCAR and tfCAS and determine the primary predictors of 30-day and 1-year mortality following TCAR.

METHODS

Data from the Vascular Quality Initiative for patients undergoing TCAR or tfCAS from January 2016 to December 2022 were analyzed. 1:1 propensity score matching using the nearest-neighbor method was used to adjust baseline demographics and clinical characteristics. Kaplan-Meier survival analysis and Cox Proportional Hazard Regression were used to evaluate long-term outcomes. Iterative stepwise multiple logistic regression analysis and Cox Proportional Hazard Regression were used to identify predictors of 30-day and 1-year mortality, respectively, based upon preoperative, intraoperative, and postoperative factors.

RESULTS

A total of 70 237 patients were included in analysis (TCAR=58.7%, tfCAS=41.3%). Transcarotid artery revascularization patients were older and had higher rates of comorbid conditions and high-risk medical and anatomic features than tfCAS patients. Propensity score matching yielded 22 322 pairs with no major differences between groups except that TCAR patients were older (71.6 years vs 70.8 years). At 3 years, TCAR was associated with a 24% reduction in hazard of death compared with tfCAS (hazard ratio [HR]=0.76, 95% confidence interval [CI]=0.71-0.82, p<0.001), for both symptomatic and asymptomatic patients. This survival advantage was established in the first 6 months (HR=0.59, 95% CI=0.53-0.62, p<0.001), with no difference in mortality risk from 6 months to 36 months (HR=0.95, 95% CI=0.86-1.05, p=0.31). Transcarotid artery revascularization was also associated with decreased hazard for 3-year stroke (HR=0.81, 95% CI=0.66-0.99, p=0.04) and stroke or death (HR=0.81, 95% CI=0.76-0.87, p<0.001) compared with tfCAS. The top predictors for 30-day and 1-year mortality were postoperative complications. The primary independent predictor was the occurrence of postoperative stroke.

CONCLUSIONS

Transcarotid artery revascularization had a sustained mid-term survival advantage associated over tfCAS, with the benefit being established primarily within the first 6 months. Notably, our findings highlight the importance of postoperative stroke as the primary independent predictor for 30-day and 1-year mortal.

CLINICAL IMPACT

The ongoing debate over the superiority of TCAR compared to tfCAS and CEA has been limited by a lack of comparative studies examining the impact of pre-operative symptoms on outcomes. Furthermore, data are scarce on mid-term outcomes for TCAR beyond the perioperative period. As a result, it remains uncertain whether the initial benefits of stroke and death reduction observed with TCAR over tfCAS persist beyond one year. Our study addresses these gaps in the literature, offering evidence to enable clinicians to assess the efficacy of TCAR for up to three years. Additionally, our study seeks to identify risk factors for postoperative mortality following TCAR, facilitating optimal patient stratification.

Neck radiation is not associated with increased risk of perioperative adverse events after transcarotid artery revascularization or transfemoral carotid artery stenting

OBJECTIVE

It is unclear whether patients with prior neck radiation therapy (RT) are at high risk for carotid artery stenting (CAS). We aimed to delineate 30-day perioperative and 3-year long-term outcomes in patients treated for radiation-induced stenotic lesions by the transfemoral carotid artery stenting (TFCAS) or transcarotid artery revascularization (TCAR) approach to determine comparative risk and to ascertain the optimal intervention in this cohort.

METHODS

Data were extracted from the Vascular Quality Initiative CAS registry for patients with prior neck radiation who had undergone either TCAR or TFCAS. The Student t-test and the χ2 test were used to compare baseline patient characteristics. Multivariable logistic regression and Cox Hazard Proportional analysis were used to compare perioperative and long-term differences between patients with and without prior neck radiation following TCAR and TFCAS. Kaplan-Meier estimator was used to determine the incidence of 3-year adverse events.

RESULTS

A total of 72,656 patients (TCAR, 40,879; TFCAS, 31,777) were included in the analysis. Of these, 4151 patients had a history of neck radiation. Patients with a history of neck radiation were more likely to be younger, white, and have fewer comorbidities than patients with no neck radiation history. After adjustment for confounding factors, there was no difference in relative risk of 30-day perioperative stroke (P = .11), death (P = .36), or myocardial infarction (MI) (P = .61) between TCAR patients with or without a history of neck radiation. The odds of stroke/death (P = .10) and stroke/death/MI (P = .07) were also not statistically significant. In patients with prior neck radiation, TCAR had lower odds for in-hospital stroke/death/MI (odds ratio, 0.59; 95% confidence interval [CI], 0.35-0.99; P = .05) and access site complications than TFCAS. At year 3, patients with prior neck radiation had an increased hazard for mortality after TCAR (hazard ratio [HR], 1.24; 95% CI, 1.02-1.51; P = .04) and TFCAS (HR, 1.33; 95% CI, 1.12-1.58; P = .001). Patients with prior neck radiation also experienced an increased hazard for reintervention after TCAR (HR, 2.16; 95% CI, 1.45-3.20; P < .001) and TFCAS (HR, 1.67; 95% CI, 1.02-2.73; P<.001).

CONCLUSIONS

Patients with prior neck radiation had a similar relative risk of 30-day perioperative adverse events as patients with no neck radiation after adjustment for baseline demographics and disease characteristics. In these patients, TCAR was associated with reduced odds of perioperative stroke/death/MI as compared with TFCAS. However, patients with prior neck radiation were at increased risk for 3-year mortality and reintervention.

Da Vinci Meets Globus Excelsius GPS: A Totally Robotic Minimally Invasive Anterior and Posterior Lumbar Fusion

BACKGROUND

Minimally invasive approaches to the spine via anterior and posterior approaches have been increasing in popularity, culminating in the development of robot-assisted spinal fusions. The da Vinci surgical robot has been used for anterior lumbar interbody fusion (ALIF), with promising results. Similarly, multiple spinal robots have been developed to assist placement of posterior pedicle screws. However, no previous cases have reported on using robots for both anterior and posterior fixation in a single surgery. We present a technical note on the first reported case of a totally robotic minimally invasive anterior and posterior lumbar fusion and instrumentation.

METHODS

A 65-year-old man with chronic low back pain and left greater than right lower extremity radiculopathy was found to have grade 1 spondylolisthesis at L5/S1 that worsened on standing upright. He underwent ALIF using a da Vinci robotic approach, followed by percutaneous posterior instrumented fusion with the Globus Excelsius GPS robot.

RESULTS

The patient did well postoperatively, with improvement of back and leg pain at 3 months follow-up. Radiography confirmed appropriate placement of the interbody cage and pedicle screws.

CONCLUSIONS

All-robotic placement of both ALIF and posterior lumbar pedicle fixation may be safe, feasible, and efficacious.

Carotid Stenosis Patients with a Remote History of Cerebrovascular Events have Increased Risk of Major Adverse Events Over Asymptomatic Patients

INTRODUCTION

Asymptomatic patients with a remote history of transient ischemic attack (TIA) or stroke are not well studied as a separate population from asymptomatic patients with no prior history of TIA or stroke. We compared in-hospital outcomes following transcarotid artery revascularization (TCAR) and transfemoral carotid artery stenting (TFCAS) among symptomatic, remote history of neurologic symptoms, and asymptomatic patients.

METHODS

Data from patients in the Vascular Quality Initiative database undergoing TCAR (Jan 2017 to Apr 2020) or TFCAS (May 2005 to Apr 2020) was analyzed. Symptomatic status was defined as TIA and/or stroke occurring within 180 days prior to procedure. Asymptomatic status was divided into patients with no history of TIA/stroke (asymptomatic) and TIA/stroke occurring more than 180 days prior to procedure (remote history of neurologic symptoms). Student's T-test and Pearson Chi-Squared test were used to compare baseline patient characteristics and outcomes. Multivariate logistic regression was used to adjust for significant between-group differences in baseline characteristics.

RESULTS

There were 7,158 patients who underwent TCAR (symptomatic: 2,574; asymptomatic: 3,689; asymptomatic with a remote history of neurologic symptoms: 895) and 18,023 patients who underwent TFCAS (symptomatic: 6,195; asymptomatic: 10,333; asymptomatic with a remote history of neurologic symptoms: 1,495). Regardless of symptom status, the mean patient age was 73 years for TCAR and 69 years for TFCAS. 64% of patients in the study were male and 36% of patients were female. Mean long-term follow up data ranged between 208 to 331 days within the three patient groups. Carotid stenosis patients with a remote history of neurologic symptoms had higher rates of TIA, stroke, TIA/stroke, stroke/death, and stroke/death/MI than asymptomatic patients, and these rates were similar to those of symptomatic patients. Comparing TCAR and TFCAS among remote history of neurologic symptom patients, there were statistically significant reductions in the odds of stroke/death (OR: 0.46, 95% CI: 0.27-0.84, P = 0.011) and stroke/death/MI (OR: 0.51, 95% CI: 0.30-0.87, P = 0.013) after TCAR. This was likely driven by the increased rate of death for TFCAS remote history of neurologic symptoms patients (0.9%) compared to asymptomatic patients (0.6%).

CONCLUSION

Asymptomatic patients with a remote history of TIA/stroke do not have the same outcomes as asymptomatic patients without a history of TIA/stroke and are at higher risk of adverse in-hospital events. Patients with a remote history of TIA/stroke have increased risk of in-hospital death after TFCAS and may benefit from TCAR.

Population Pharmacokinetic Model for Tramadol and O-desmethyltramadol in Older Patients

BACKGROUND AND OBJECTIVES

Tramadol is commonly prescribed to manage chronic pain in older patients. However, there is a gap in the literature describing the pharmacokinetic parameters for tramadol and its active metabolite (O-desmethyltramadol [ODT]) in this population. The objective of this study was to develop and evaluate a population pharmacokinetic model for tramadol and ODT in older patients.

METHODS

Twenty-one patients who received an extended-release oral tramadol dose (25-100 mg) were recruited. Tramadol and ODT concentrations were determined using a validated liquid chromatography/tandem mass spectrometry method. A population pharmacokinetic model was developed using non-linear mixed-effects modelling. The performance of the model was assessed by visual predictive check.

RESULTS

A two-compartment, first-order absorption model with linear elimination best described the tramadol concentration data. The absorption rate constant was 2.96/h (between-subject variability [BSV] 37.8%), apparent volume of distribution for the central compartment (V₁/F) was 0.373 l (73.8%), apparent volume of distribution for the peripheral compartment (V₂/F) was 0.379 l (97.4%), inter-compartmental clearance (Q) was 0.0426 l/h (2.19%) and apparent clearance (CL/F) was 0.00604 l/h (6.61%). The apparent rate of metabolism of tramadol to ODT (k_t) was 0.0492 l/h (78.5%) and apparent clearance for ODT (CL_m) was 0.143 l/h (21.6%). Identification of Seniors at Risk score (ISAR) and creatinine clearance (CrCL) were the only covariates included in the final model, where a higher value for the ISAR increased the maximum concentration (C_max) of tramadol and reduced the BSV in Q from 4.71 to 2.19%. A higher value of CrCL reduced tramadol C_max and half-life (T_1/2) and reduced the BSV in V₂/F (from 148 to 97.4%) and in CL/F (from 78.9 to 6.61%).

CONCLUSION

Exposure to tramadol increased with increased frailty and reduced CrCL. Prescribers should consider patients frailty status and CrCL to minimise the risk of tramadol toxicity in such cohort of patients.

Review of Malpractice Lawsuits in the Diagnosis and Management of Aortic Aneurysms and Aortic Dissections

OBJECTIVE

Aortic aneurysms and dissections are prevalent causes of morbidity and mortality. The management of aortic pathologies may be called into question in malpractice suits. Malpractice claims were analyzed to understand common reasons for litigation, medical specialties involved, patient injuries, and outcomes.

METHODS

Litigation cases in the Westlaw database from September 1st, 1987 to October 23 rd, 2019 were analyzed. Search terms included "aortic aneurysm" and "aortic dissection." Data on plaintiff, defendant, litigation claims, patient injuries, misdiagnoses, and case outcomes were collected and compared for aortic aneurysms, aortic dissections, and overall cases.

RESULTS

A total of 346 cases were identified, 196 involving aortic aneurysms and 150 aortic dissections. Physician defendants were emergency medicine (29%), cardiology (20%), internal medicine (14%), radiology (11%), cardiothoracic (10%) and vascular surgery (10%). Litigation claims included "failure to diagnose and treat" (61%), "delayed diagnosis and treatment" (21%), "post-operative complications after open repair" (10%) and "negligent post-operative care" (10%). Patients with aneurysms presented with abdominal (63%) and back pain (37%), while dissections presented with chest pain (78%), abdominal pain (15%), and shortness of breath (14%). Misdiagnoses included gastrointestinal (12%), other cardiovascular (9%), and musculoskeletal conditions (9%), but many were not specified (58%). Overall, 83% of cases were wrongful death suits. Injuries included loss of consortium (23%), emotional distress (19%), and bleeding (17%). In 53% of the cases, the jury ruled in favor of the defendant. 25% of cases ruled for the plaintiff. 22% of cases resulted in a settlement. The mean rewarded for each case was $1,644,590.66 (SD: $5,939,134.58; Range: $17,500-$68,035,462).

CONCLUSION

For aortic pathologies, post-operative complications were not prominent among the reasons why suits were brought forth. This suggests improvements in education across all involved medical specialties may allow for improved diagnostic accuracy and efficient treatment, which could then translate to a decrease in associated litigation cases.

Meta-Analysis of Anticoagulation Therapy for the Prevention of Cardiovascular Events in Patients With Peripheral Arterial Disease

Peripheral artery disease (PAD) remains a major cause of morbidity and future cardiovascular events despite advancement in the surgical interventions and optimal medical therapy. The aim of our study is to evaluate the efficacy and safety of anticoagulation (AC) therapy for reducing cardiovascular and limb events in patients with PAD. PUBMED, Medline, and Cochrane Library were searched through 2020 for randomized clinical trials comparing major adverse cardiovascular events (MACE) and risk of major bleeding (MB), between AC and standard of care (SOC) therapy, among patients with PAD. Meta-analysis was performed using weighted pooled absolute risk difference (RD) with 95% confidence interval (CI) and fixed effects model for overall and sub-groups of full dose (FD) and low dose (LD) AC therapies. Amongst 17,684 patients from 7 different studies, the addition of AC to SOC therapy was associated with MACE reduction (RD -0.022, 95% CI -0.033 to -0.012, p <0.001) and increased MB (RD 0.02, 95% CI 0.014 to 0.025, p <0.001). For FD, MACE reduction was (RD -0.021, 95% CI -0.042 to 0.001, p = 0.061) and MB (RD 0.036, 95% CI 0.025 to 0.047, p <0.001). For LD, MACE reduction was (RD -0.023, 95% CI -0.035 to -0.011, p <0.001) and MB (RD 0.011, 95% CI 0.005 to 0.017, p <0.001). In conclusion, addition of AC to the current SOC therapy can mitigate future MACE events in patients with PAD albeit at risk of increased bleeding. LD AC is associated with an efficacy/safety net benefit compared to FD AC therapy.

Acute thrombotic manifestations of coronavirus disease 2019 infection: Experience at a large New York City health care system

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a novel coronavirus that has typically resulted in upper respiratory symptoms. However, we have encountered acute arterial and venous thrombotic events after COVID-19 infection. Managing acute thrombotic events from the novel virus has presented unprecedented challenges during the COVID-19 pandemic. In our study, we have highlighted the unique treatment required for these patients and discussed the role of anticoagulation for patients diagnosed with COVID-19.

METHODS

The data from 21 patients with laboratory-confirmed COVID-19 disease and acute venous or arterial thrombosis were collected. The demographics, comorbidities, home medications, laboratory markers, and outcomes were analyzed. The primary postoperative outcome of interest was mortality, and the secondary outcomes were primary patency and morbidity. To assess for significance, a univariate analysis was performed using the Pearson χ² and Fisher exact tests for categorical variables and the Student t test for continuous variables.

RESULTS

A total of 21 patients with acute thrombotic events met our inclusion and exclusion criteria. Most cases were acute arterial events (76.2%), with the remainder venous cases (23.8%). The average age for all patients was 64.6 years, and 52.4% were male. The most prevalent comorbidity in the group was hypertension (81.0%). Several markers were markedly abnormal in both arterial and venous cases, including an elevated neutrophil/lymphocyte ratio (8.8) and D-dimer level (4.9 μg/mL). Operative intervention included percutaneous angiography in 25.00% of patients and open surgical embolectomy in 23.8%. Most of the patients who had undergone arterial intervention had developed a postoperative complication (53.9%) compared with a 0% complication rate after venous interventions. Acute kidney injury on admission was a factor in 75.0% of those who died vs 18.2% in the survivors (P = .04).

CONCLUSIONS

We have described our experience in the epicenter of the pandemic of 21 patients who had experienced major thrombotic events from infection with COVID-19. The findings from our cohort have highlighted the need for increased awareness of the vascular manifestations of COVID-19 and the important role of anticoagulation for these patients. More data are urgently needed to optimize treatment and prevent further vascular complications of COVID-19 infections.

The Effect of Patient and Hospital Characteristics on Total Costs of Peripheral Bypass in New York State

INTRODUCTION

With the aging U.S. population, peripheral vascular procedures will become increasingly common. The objective of this study is to characterize the factors associated with increased total costs after peripheral bypass surgery.

METHODS

Data for 34,819 patients undergoing peripheral bypass surgery in NY State were extracted using the Statewide Planning and Research Cooperative System (SPARCS) database for years 2009-2017. Patient demographics, All Patient Refined Diagnostic Related Groups (APR) severity score, mortality risk, hospital volume, and length of stay data were collected. Primary outcomes were total costs and length of stay. Data were analyzed using univariate and multivariate analysis.

RESULTS

28.1% of peripheral bypass surgeries were performed in New York City. 7.9% of patients had extreme APR severity of illness whereas 32.0% had major APR severity of illness. 6.3% of patients had extreme risk of mortality and 1 in every 5 patients (20%) had major risk of mortality. 24.9% of patients were discharged to a facility. The mean length of stay (LOS) was 9.9 days. Patient LOS of 6-11 days was associated with +$2,791.76 total costs. Mean LOS of ≥ 12 days was associated with + $27,194.88 total costs. Multivariate analysis revealed risk factors associated with an admission listed in the fourth quartile of total costs (≥$36,694.44) for peripheral bypass surgery included NYC location (2.82, CI 2.62-3.04), emergency surgery (1.12, CI 1.03-1.22), extreme APR 2.08, 1.78-2.43, extreme risk of mortality (2.73, 2.34-3.19), emergency room visit (1.68, 1.57-1.81), discharge to a facility (1.27, CI 1.15-1.41), and LOS in the third or fourth quartile (11.09, 9.87-12.46).

CONCLUSION

The cost of peripheral bypass surgery in New York State is influenced by a variety of factors including LOS, patient comorbidity and disease severity, an ER admission, and discharge to a facility.

A Review of the Evolution of Abdominal Aortic Endografts and Future Directions

INTRODUCTION

Over the years, endovascular aortic aneurysm repair (EVAR) has become the gold-standard of therapy for abdominal aortic aneurysm (AAA) repairs. This study aims to analyze the evolution of stent graft devices and discuss the future direction of technological development.

MATERIALS AND METHODS

In this paper, we will review prior eras of graft development (1992 to 2019) that included physician-made devices (era one), industry-made devices (era two), branch devices (era three), and fenestrated devices (era four). Additionally, future advancements that aim to overcome issues with short aneurysm necks, involvement of proximal visceral branches, and formation of endoleaks will be discussed.

RESULTS

Future devices of note include a more conformable version of the EXCLUDER® device (W. L. Gore & Associates, Inc., Newark, Delaware) to better steer the top of the graft and modify for angulated necks, a version of the Endurant® device to include EndoAnchors (Medtronic plc, Minneapolis, Minnesota) to prevent formation of endoleaks, a novel Nellix® EVAS II device (Endologix Inc., Irvine, California) with aneurysm sac filling to prevent endoleaks and exclude the aneurysm sac, and an expanded Zenith® fenestrated device (Cook Medical Inc., Bloomington, Indiana) to include more visceral branches. This is in the setting of more recent advancements like pivoting fenestrated branch devices for "off-shelf" use and aneurysm repair that now extends to the thoracic aorta.

CONCLUSION

With each iteration of devices, EVAR has evolved to overcome technical challenges and offer expanded applicability to different types of AAAs.

Enhancing rare variant interpretation in inherited arrhythmias through quantitative analysis of 5182 cases from long QT syndrome and Brugada syndrome consortia cohorts and gnomAD population controls

Background/Introduction

Guidelines for variant interpretation in Mendelian disease set stringent criteria to report a variant as (likely) pathogenic, prioritising control of false positive rate over test sensitivity and diagnostic yield, and require customisation for the specific genetic characteristics of gene-disease dyads. Inherited arrhythmias like long QT syndrome (LQTS) and Brugada syndrome (BrS) are genetically heterogeneous, with missense variants constituting the preponderance of disease-causing variants. Evidence from family segregation or functional assays to confirm pathogenicity are often unavailable or impractical in clinical genetic testing, leading to high rates of variants of uncertain significance and false negative test results.

Methods

We compared rare variant frequencies from 1847 LQTS (KCNQ1, KCNH2, SCN5A) and 3335 BrS (SCN5A) cases from the International LQTS/BrS Genetics Consortia to population-specific gnomAD data. We propose disease-specific criteria for ACMG/AMP evidence classes – rarity (PM2/BS1 rules) and enrichment of individual (PS4) and domain-specific (PM1) variants in cases over controls.

Results

Rare SCN5A variant prevalence differed between BrS cases with spontaneous (28.7%) versus induced (15.8%) type 1 Brugada ECG (p=1.3x10–13) and between European (20.8%) and Japanese (8.9%) patients (p=8.8x10–18). Transmembrane regions and specific N-terminus (KCNH2) and C-terminus (KCNQ1/KCNH2) domains were characterised by high enrichment of case variants and &gt;95% probability of pathogenicity. Applying the customised rules, 17.5% of European BrS cases and 73.7% of European LQTS cases had variants classified as (likely) pathogenic, compared to estimated diagnostic yields (case excess over gnomAD) of 19.3%/82.6%.

Conclusions

Large case/control datasets enable quantitative implementation of ACMG/AMP guidelines and increased sensitivity for inherited arrhythmia genetic testing.

Classification of Brugada/LQTS variants

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Dutch Heart Foundation, Netherlands Organisation for Scientific Research

Acute thrombotic events as initial presentation of patients with COVID-19 infection

We describe three patients with COVID-19 who presented with an acute vascular event rather than with typical respiratory symptoms. These patients were all subsequently found to have laboratory-confirmed COVID-19 infections as the likely cause of their thrombotic event. The primary presentation of COVID-19 infection as a thrombotic event rather than with respiratory symptoms has not been described elsewhere. Our cases and discussion highlight the thrombotic complications caused by COVID-19; we discuss management of these patients and explore the role of anticoagulation in patients diagnosed with COVID-19.

668Principal component analysis can identify ventricular regions with highest variability in the arrhythmogenic substrate of ventricular tachycardia patients

Introduction

Left ventricle (LV) substrate can be characterized by imaging modalities providing physiological variables (tissue perfusion, ischemia, etc.) grouped in a complex dataset. Principal Component Analysis (PCA) can identify the dataset variables that best explain its variance. Variables linked to substrate arrhythmogenicity will lead PCA to identify LV regions most influenced by the variables on a LV 3D geometry.

Purpose

To evaluate whether regions identified by PCA correspond to regions targeted by physicians in a ventricular tachycardia (VT) ablation procedure.

Methods

Ischemic VT subjects underwent SPECT/CT perfusion imaging (rest and stress) prior to LV voltage mapping with the cardiac mapping system. Co-registration allowed projection of ablation sites onto SPECT/CT geometries. PCA retrospectively analyzed the following dataset: tissue perfusion (rest and stress), tissue ischemia and the local (1cm2 sub-regions) stress-rest difference for: 1) standard deviation (STD) and 2) skewness (Skew). PCA components (PCAc) explaining ≥85% of the total variance were plotted on the LV 3D geometry to display regions highly influenced by the dataset variables (see figure below).

Results

Ten subjects (9 males, 66 ± 8 years old, LVEF 37 ± 11%) underwent co-registration. In 7/10 subjects, tissue perfusion (in PCAc#1) and ischemia (in PCAc#2) were most influential on LV regions variance. Ischemia and low perfusion (≤40%) areas equaled 32 ± 19 % of the LV with 21 ± 23% of these areas highly involved in the arrhythmogenic substrate (≥75% of explained LV variance). The location of 63 ± 18% of ablation sites were &lt;1 cm from areas explaining ≥50% of LV variance.

Conclusion

Preliminary results showed that PCA can synthesize the influence of different perfusion derived variables, like tissue perfusion and ischemia, used in SPECT/CT imaging of the LV. Further analysis is needed to confirm whether this could be used to select VT ablation targets.

Abstract Figure.

Hybrid Repair Techniques for Complex Aneurysms and Dissections Involving the Aortic Arch and Thoracic Aorta

Aortic aneurysms involving the ascending aorta, aortic arch, and descending thoracic aorta have been a challenging entity to surgically treat for over 60 years. Despite the mortality of the disease, early open surgical procedures also had significant morbidity and mortality. The inherent risk in treating multiple anatomic segments simultaneously led to the innovation of the staged elephant trunk (ET) approach by Borst in 1983. To avoid the thoracotomy and associated complications related to the second stage of the procedure, an endovascular completion paradigm was begun by Volodos in 1991. This theoretical hybrid technique combinined shorter and less elaborate open supra-aortic trunk debranching with less invasive endovascular exclusion and has grown since then in terms of different approaches and case volume. The rise of thoracic endovascular aortic repair (TEVAR) combined with debranching bypass has allowed certain lesions to be treated without a large scale intrathoracic open surgical procedure. The complexity and extensiveness of certain lesions, however, has necessitated a hybrid approach such as the frozen elephant trunk (FET) and the standard ET with second stage TEVAR. The former has been used to treat multifocal degenerative aneurysms, chronic dissections with aneurysm, and acute extensive dissections. After conventional proximal aortic replacement, a stent-graft (SG) is delivered antegrade through the transected arch where it is sutured proximally and then "frozen" distally via endovascular means. The FET has the advantage of avoiding a second stage, but potentially introduces a greater rate of spinal cord ischemia compared to the standard elephant trunk. Improvements on the FET procedure have included the development of more advanced hybrid SG such as the Vascutek® Thoraflex™ Hybrid graft (Vascutek Ltd, Scotland, UK), which consists of a distal en,dograft sealed to a proximal four-branched Vascutek Gelweave™ Vascutek Ltd, Scotland, UK) and incorporated sewing collar. While open surgery continues to be a component of complex aortic arch aneurysms, the development of hybrid devices that can bridge the gap between open and endovascular surgery will continue to flourish.

Abdominal Aortic Aneurysm With Renal Arteries Originating Above the Superior Mesenteric Artery

A 63-year-old female presented to clinic following an incidental finding of an abdominal aortic aneurysm (AAA). Preoperative imaging was consistent with an infrarenal AAA over 5-cm in diameter with both renal arteries originating above the superior mesenteric artery (SMA). The patient subsequently underwent an endovascular aneurysm repair (EVAR) using the AFX stent-graft (Endologix, Inc, Irvine, Calif). Notably, the proximal stent-graft piece was unsheathed with the image intensifier in a lateral position to ensure deployment below the SMA. Postoperative course was unremarkable and the patient is currently recovering well.