Changes in Arterial Stiffness and N-terminal pro-brain natriuretic peptide Levels after Endovascular Repair of Descending Thoracic Aorta

Screening for Peripheral Vascular Stiffness in Lipedema Patients by Automatic Electrocardiogram-Based Oscillometric Detection

Body mass index (BMI) is seen as a predictor of cardiovascular disease (CVD) in lipedema patients. A valid predictor of CVD is increased aortic stiffness (IAS), and previous research described IAS in lipedema. However, it is not known if this applies to all patients. In this cross-sectional single-center cohort study, peripheral pulse wave velocity (PWV) as a non-invasive indicator of aortic stiffness was measured in 41 patients with lipedema, irrespective of stage and without pre-existing cardiovascular conditions or a history of smoking and a maximum body mass index (BMI) of 35 kg/m2. Automatically electrocardiogram-triggered oscillometric sensor technology by the Gesenius-Keller method was used. Regardless of the stage of lipedema disease, there was no significant difference in PWV compared to published standard values adjusted to age and blood pressure. BMI alone is not a predictor of cardiovascular risk in lipedema patients. Measuring other anthropometric factors, such as the waist-hip ratio or waist-height ratio, should be included, and the existing cardiovascular risk factors, comorbidities, and adipose tissue distribution for accurate risk stratification should be taken into account. Automated sensor technology recording the PWV represents a valid and reliable method for health monitoring and early detection of cardiovascular risks.

Hostile Hemodynamics in Distal Stent Graft-Induced New Entry Prior to Aortic Rupture: A Comparison of Transient versus Steady-State CFD Simulations

BACKGROUND

 Computational fluid dynamics (CFD) simulations model blood flow in aortic pathologies. The aim of our study was to understand the local hemodynamic environment at the site of rupture in distal stent graft-induced new entry (dSINE) after frozen elephant trunk with a clinically time efficient steady-flow simulation versus transient simulations.

METHODS

 Steady-state simulations were performed for dSINE, prior and after its development and prior to aortic rupture. To account for potential turbulences due geometric changes at the dSINE location, Reynolds-averaged Navier-Stokes equations with the realizable k-ε model for turbulences were applied. Transient simulations were performed for comparison. Hemodynamic parameters were assessed at various locations of the aorta.

RESULTS

 Post-dSINE, jet-like flow due to luminal narrowing was observed which increased prior to rupture and resulted in focal neighbored regions of high and low wall shear stress (WSS). Prior to rupture, aortic diameter at the rupture site increased lowering WSS at the entire aortic circumference. Concurrently, WSS and turbulence increased locally above the entry tear at the inner aortic curvature. Turbulent kinetic energy and WSS elevation in the downstream aorta demonstrated enhanced stress on the native aorta. Results of steady-state simulations were in good qualitative agreement with transient simulations.

CONCLUSION

 Steady-flow CFD simulations feasible at clinical time scales prior to aortic rupture reveal a hostile hemodynamic environment at the dSINE rupture site in agreement with lengthy transient simulations. Consequently, our developed approach may be of value in treatment planning where a fast assessment of the local hemodynamic environment is essential.

Arterial Stiffness and Aortic Aneurysmal Disease - A Narrative Review

It has been documented that large-artery stiffness is independently associated with increased cardiovascular risk and may potentially lead to heart and kidney failure and cerebrovascular disease. A systematic review of studies investigating changes in arterial stiffness in patients undergoing endovascular repair of aortic disease was conducted. In addition, a review of the available literature was performed, analyzing findings from studies using the cardio-ankle vascular index (CAVI) as a marker of arterial stiffness. Overall, 26 studies were included in the present analysis. Our research revealed a high heterogeneity of included studies regarding the techniques used to assess the aortic stiffness. Aortic stiffness was assessed by pulse wave velocity (PWV), elastic modulus (Ep), and augmentation index (AI). Currently a few studies exist investigating the role of CAVI in patients having an aortic aneurysm or undergoing endovascular aortic repair. The majority of studies showed that the treatment of an abdominal aortic aneurysm (AAA) either with open repair (OR) or endovascular aortic repair (EVAR) reduces aortic compliance significantly. Whether EVAR reconstruction might contribute a higher effect on arterial stiffness compared to OR needs further focused research. An increase of arterial stiffness was uniformly observed in studies investigating patients following thoracic endovascular aortic repair (TEVAR), and the effect was more pronounced in young patients. The effects of increased arterial stiffness after EVAR and TEVAR on the heart and the central hemodynamic, and an eventual effect on cardiac systolic function, need to be further investigated and evaluated in large studies and special groups of patients.

Echocardiographic Changes in Cardiac Function After Thoracic Endovascular Aortic Repair: A Systematic Review and Meta-Analysis

BACKGROUND

Evidence suggests thoracic stent grafts increase the aortic stiffness postimplantation. Our objective was to examine the effect of thoracic aortic stenting on heart function, as demonstrated with echocardiography.

METHODS

We considered nonrandomized studies examining echocardiographic parameters (left ventricle ejection fraction (LVEF), left ventricle end-diastolic (LVED) and end-systolic diameter (LVESD), posterior wall thickness (LVPWT), interventricular septal thickness (IVST), mass, and mass index) pre and poststent graft implantation in patients with thoracic aortic diseases (aneurysm, dissection, and blunt injury). MEDLINE and CENTRAL were searched (up to March 2021) for eligible studies. The National Institutes of Health Quality Assessment Tool was used for risk of bias assessment. Echocardiographic data pre and postimplantation were compared using the pooled standardized mean difference (SMD) and 95% confidence interval (CI).

RESULTS

Four studies were included in the meta-analysis. Three of the studies were judged to be "good" quality and one "fair". Nonsignificant differences pre and postimplantation were found for ejection fraction (SMD = -0.53, 95% CI = -1.8 to 0.728, P = 0.406), IVST (SMD = -0.79, 95%, CI = -3.25 to 1.66, P = 0.52), EDD (SMD = -0.10, 95% CI = -0.48 to 0.28, P = 0.60), ESD (SMD = -0.66, 95% CI = -2.35 to 1.02, P = 0.44), and PWT (SMD = -2.20, 95% CI = -5.89 to 1.47, P = 0.24). A trend toward an increase in mass postimplantation was found (SMD = 0.28, 95%, CI = -0.03 to 0.60, P = 0.08), but there was no significant difference in mass index (SMD = 0, 95%, CI = -0.195 to 0.195, P = 1).

CONCLUSIONS

Thoracic aortic stenting does not appear to significantly impact cardiac physiology as indicated by echocardiographic parameters.

Postoperative management in patients with complex aortic aneurysms

Patients with complex aortic aneurysms (CAA) are often high risk due to advanced age and widespread atherosclerosis affecting numerous vascular territories. Therefore, a thorough perioperative evaluation is needed prior to performing in any type of aortic repair, regardless of whether an endovascular or open surgical approach is selected. Because these operations are technically demanding and often result in end organ ischemia, it is not surprising that complex aortic repair carries significant risk of morbidity and mortality. Disabling complications such as dialysis, major stroke and paraplegia constitute the main limitation of complex aortic repair. The aim of this article was to review postoperative management to mitigate complications after CAA repair.

TEVAR and EVAR, the unknown knowns of the cardiovascular hemodynamics; and the immediate and long-term consequences of fabric material on major adverse clinical outcome

This review discusses the impact of endovascular aneurysm repair on cardiovascular (CV) hemodynamics and the role of stent-graft material, i.e., polytetrafluoroethylene (PTFE) vs. polyester in post-procedural outcomes. Endovascular aneurysm repair has been widely employed in the last decades for thoracic and abdominal aneurysm repair. However, aortic endografts are stiff and alter the native flow hemodynamics. This failure to simulate the native aorta could lead to added strain on the heart, manifesting as increased left ventricular strain, higher pulse pressure, and congestive heart failure later. This could result in adverse CV outcomes. Also, evidence is mounting to support the implication of stent-graft materials, i.e., PTFE vs. polyester, in adverse post-procedural outcomes. However, there is an absence of level one evidence. Therefore, the only way forward is to plan and perform a randomised controlled trial to demonstrate the alterations in the CV hemodynamics in the short and long run and compare the available stent-graft materials regarding procedural and clinical outcomes. We believe the best solution, for now, would be to reduce the stented length of the aorta. At the same time, in the longer term, encourage continuous improvement in stent-graft materials and design.

High risk of early and late cardiovascular events after endovascular aortic aneurysm repair

OBJECTIVE

The objective of this population-based study was to analyze short- and long-term major adverse cardiovascular events (MACE) after endovascular repair of ruptured or non-ruptured thoracic (TAA) and abdominal aortic aneurysms (AAA).

METHODS

Nationwide retrospective registry study including all patients that underwent endovascular repair (thoracic endovascular aortic repair, TEVAR; abdominal endovascular aneurysm repair, EVAR) for non-ruptured/intact (iAAA/iTAA) or ruptured (rAAA/rTAA) abdominal or thoracic aneurysms between 2000 and 2018. The primary outcome was a composite of cardiovascular death, stroke, or myocardial infarction (MACE).

RESULTS

There were 8641 patients with TAA and AAA; 634 TEVAR procedures [iTAA 488; rTAA 146] and 8007 EVAR procedures [iAAA 7071; rAAA 936] were performed. MACE incidence at 90-day after TEVAR for iTAA was 10.2% and for rTAA 26.7% [HR 3.02, 95% CI 1.99-4.6]; MACE at 90-day after EVAR for iAAA was 3.7% and for rAAA 26.9 % [HR 8.5, 95% CI: 7.16-10.11]. There was a higher cumulative incidence of MACE at 90-day after TEVAR for iTAA compared to EVAR for iAAA [HR 2.82, 95% CI 2.09-3.82] but no difference between the procedures after ruptured aneurysm repair. The median follow-up time was 3.28 years [IQR 1.31-5.94]. There was no long-term difference in MACE between EVAR and TEVAR after ruptured [90d-5y: HR 1.14, 95% CI 0.76-1.71; 5y-10y: HR 0.78, 95% CI 0.31-1.96] or intact [90d-5y: HR 1.19, 95% CI 0.97-1.46; 5y-10y: HR 0.82, 95% CI 0.56-1.21] aneurysm repair. Female gender had higher long-term incidence of MACE after intact [HR 1.14, 95% CI 1.03-1.27] and ruptured [HR 1.36, 95% CI 1.12-1.65] endovascular aortic aneurysm treatment. After intact aneurysms repair; age [HR 1.05, 95% CI 1.04-1.05], history of angina pectoris [HR 1.19, 95% CI 1.08-1.32], heart failure [HR 1.90, 95% CI 1.69-2.13], and stroke [HR 1.33, 95% CI 1.15-1.53] were associated with MACE.

CONCLUSIONS

This nationwide cohort study demonstrated still a high risk of early and late cardiovascular events after endovascular aortic repair. Comprehensive strategies for postoperative cardiovascular disease prevention may here be needed.

Aortic Healing Appears to Occur Rapidly after Successful Endovascular Sealing of Blunt Thoracic Aortic Injury

OBJECTIVES

The traumatic nature of blunt thoracic aortic injury (BTAI) would suggest that healing of the aorta would occur once the injured area is shielded from aortic pressure. This would be in contrast to degenerative aortic diseases which often continue to degenerate despite coverage. We hypothesize that after successful thoracic aortic endografting (TEVAR) that the aorta rapidly heals itself leaving minimal to no trace of the residual injury.

METHODS

BTAI that were successfully covered with TEVAR from 2006-2019 were collected. Those with failed sealing or lack of follow up scans were excluded. Centerline aortic diameters were measured at healthy aorta 1 cm above (D1) and below the injury (D3) and at the widest point of injury (D2) on pre- and initial post-operative computed tomography (CT) scans. Post-operative CTs were examined for residual signs of aortic injury including residual peri-aortic hematoma, persistent thrombosed pseudoaneurysm, or thickened aortic wall. Diameter changes in the healthy and injured aortic segments were compared pre and post TEVAR. Aortic diameter changes were analyzed with Students t-test.

RESULTS

Twenty-four patients were identified with sealed BTAI. Mean graft diameter was 24.2 ± 3.2 mm with oversizing of 10.74 ± 6.1 % at D1 and 19.52 ± 10.22 % at D3. Postoperative CTs occurred at 61.25 ± 123.6 days with one outlier at 602 days. Injured aortic segments (D2) had significantly larger diameters compared to D1 (28.94 ± 5.08mm vs. 22.14 ± 3.08 mm, P<0.001).). After TEVAR, 23/24 (95.8%) had no residual radiographic evidence of aortic injury by 2 months. One patient had a persistent thrombosed pseudoaneurysm likely due to a more than 50% disruption of the aortic wall. Post TEVAR, there was a significant diameter reduction at D2 by 13.8% (29.10 ± 5.27mm vs. 24.8 ± 4.2 mm, p <0.001) which was within 2.45% of the mean stent graft diameter. Healthy aorta dilated to accommodate the graft by 9% at D1 (21.9 ± 3.0 vs. 23.7 ± 2.5 mm, p < 0.001) and 17% at D3 (20.6 ± 3.4 mm vs. 23.6 ± 3.2 mm, p < 0.001).

CONCLUSIONS

TEVAR promotes rapid aortic healing in BTAI with no evidence of residual aortic injury suggesting that a long term seal is not necessary. The healthy aorta dilates to the stent graft size, as expected, while the injured aortic segment heals around the stent graft and assumes its diameter as well. Massive disruption of the aortic wall may preclude early healing.

The Association of Arterial Stiffness With Significant Carotid Atherosclerosis and Carotid Plaque Vulnerability

Arterial stiffness and its valid index, the cardio-ankle vascular index (CAVI), have emerged as predictors of adverse cardiovascular outcomes. We investigated the relationship of the CAVI with significant carotid stenosis (> 50%) and the related cerebrovascular symptoms or carotid plaque echogenicity, assessed by ultrasound gray-scale median (GSM) score, at baseline and after carotid artery stenting (CAS). We prospectively enrolled 113 patients with carotid stenosis (70-99% for asymptomatic and > 50% for symptomatic participants) eligible for CAS. Age- and sex-matched individuals (n = 38) served as controls (CON). Clinical data, CAVI, and biochemical profile were obtained at baseline. Clinical assessment and CAVI measurement were performed 6 months after CAS. Compared with the CON group, the CAS group had a higher incidence of co-morbidities (diabetes, hypertension, and hyperlipidemia), higher CAVI values (9.94 ± 2.14 vs 7.85 ± .97 m/sec, P < .001), but a better lipid profile due to increased prescription of statins. The symptomatic CAS subgroup showed higher CAVI ( P < .001), high-sensitivity C-reactive protein ( P = .048), and osteoprotegerin ( P = .002) levels than the asymptomatic one. In multivariate analysis, CAVI at baseline was independently associated with the presence of significant carotid atherosclerosis (β = .695, P < .001), cerebrovascular events (β = .474, P < .001), and GSM score (β = −.275, P = .042). Raised CAVI values were independently associated with significant carotid stenosis and plaque vulnerability.

Comparison of Clinical Outcomes Following One versus Two Stage Hybrid Repair of Thoraco-Abdominal Aortic Aneurysms: A Comprehensive Meta-Analysis

OBJECTIVE

For thoraco-abdominal aortic aneurysms (TAAA), it is unclear whether it is better to perform hybrid repair in one (single) or two stages (staged). This study aimed to compare the clinical outcomes of single vs. staged hybrid repair of TAAA.

METHODS

The Medline, Embase, and Cochrane Databases (1 January 1994 to 11 May 2020) were searched for studies on hybrid repair of TAAA. Cohort studies and case series reporting outcomes of single and staged hybrid repair of TAAA were eligible for inclusion. The Newcastle-Ottawa scale and an 18 item tool were used to assess the risk of bias. The primary outcome was 30 day mortality, and the secondary outcomes included post-operative complications, overall survival, and other mid term events. A random effects model was used to calculate pooled estimates.

RESULTS

A total of 37 studies was included in the meta-analysis. The quality assessment of the included studies suggested low or moderate risk of bias. The pooled estimates for aneurysm rupture and death during stage interval were 2% (95% CI 0%-4%, I² = 0%) and 4% (95% CI 2%-7%, I² = 0%), respectively. Single repair was associated with a significantly higher 30 day risk of death when compared with patients who completed staged procedures successfully (OR 2.64, 95% CI 1.36-5.12, I² = 0%). Staged repair also had lower incidence of major adverse cardiac events (MACE) (single: 10%, 95% CI 5%-16%; staged: 2%, 95% CI 0%-5%) and intestinal complications (single: 15%, 95% CI 8%-25%; staged: 3%, 95% CI 1%-6%). For mid term outcomes, single and staged repair had comparable 12 month overall survival, aneurysm related mortality, rate of re-intervention, and graft patency.

CONCLUSION

Two stage hybrid repair may represent a better choice for patients with controlled risk of aneurysm rupture, because it can provide lower 30 day mortality risks, MACE, and intestinal complications, as well as comparable mid term outcomes. Randomised controlled trials are needed to ascertain the effect of repair staging in patients for elective TAAA.

Cardiac Stress in High-Risk Patients Undergoing Major Endovascular Surgery-Focus on Diastolic Function

OBJECTIVES

The purpose of this study was to determine the relationship between the changes in diastolic function and their association with cardiac biomarkers in the perioperative period in patients undergoing complex endovascular aortic repair.

DESIGN

Prospective observational study.

SETTING

Single-center academic hospital, central teaching hospital in Warsaw, Poland.

PARTICIPANTS

The study comprised 27 high-risk patients scheduled for elective endovascular repair of aortic aneurysm.

INTERVENTIONS

Complex endovascular procedure using branched endograft of the thoracoabdominal aorta. Branches of the stent grafts included renal arteries, the superior mesenteric artery, and the celiac trunk.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was to evaluate changes in diastolic function parameters assessed with transthoracic echocardiography at two and 24 hours postoperatively. The major secondary outcomes were changes in N-terminal pro-B-type natriuretic peptide (NT-proBNP) and troponin I concentrations, systolic function parameters, hemodynamic parameters at two and 24 hours, length of hospital stay, and 30-day mortality. There was a reduction in e' wave velocity on both the septal and lateral sides at two hours compared with the baseline (p = 0.041 and p = 0.05, respectively). There was an increase in both NT-proBNP and troponin I concentrations after surgery (p = 0.002 and p = 0.034, respectively), with troponin I peaking two hours after surgery and NT-proBNP peaking 24 hours after surgery.

CONCLUSIONS

Patients undergoing a branched endovascular aortic repair of a thoracoabdominal aortic aneurysm experience a cardiac insult that manifests with deterioration in diastolic parameters and concomitant increases of troponin and NT-proBNP concentrations. Additional large-scale prospective studies are required to confirm this phenomenon.

Conceptual Framework Development for a Double-Walled Aortic Stent-Graft to Manage Blood Pressure

A double-walled stent-graft (DWSG) design with a compressible gas layer was conceived with the goal of treating hypertension in patients receiving an aortic stent-graft. Early prototypes were developed to evaluate the design concept through static measurements from a finite element (FE) model and quasi-static inflation experiments, and through dynamic measurements from an in vitro flow loop and the three-element Windkessel model. The amount of gas in the gas layer and the properties of the flexible inner wall were the primary variables evaluated in this study. Properties of the inner wall had minimal effect on DWSG behavior, but increased gas charge led to increased fluid capacitance and larger reduction in peak and pulse pressures. In the flow loop, placement of the DWSG decreased pulse pressure by over 20% compared to a rigid stent-graft. Capacitance measurements were consistent across all methods, with the maximum capacitance estimated at 0.07 mL/mmHg for the largest gas charge in the 15 cm long prototype. Windkessel model predictions for in vivo performance of a DWSG placed in the aorta of a hypertensive patient showed pulse pressure reduction of 14% compared to a rigid stent-graft case, but pressures never returned to unstented values. These results indicate that the DWSG design has potential to be developed into a new treatment for hypertensive patients requiring an aortic intervention.

Determinants of Changes in Arterial Stiffness after Thoracic Endovascular Aortic Repair

BACKGROUND

Aortic stent grafting can cause aortic stiffening and increase pulse wave velocity (PWV), which can potentially affect long-term cardiovascular outcomes. The aim of this study was to clarify the factors contributing to increases in PWV after thoracic endovascular aortic repair (TEVAR).

METHODS

We included 64 patients with thoracic aortic pathology (51 men; mean age, 73 years) who underwent elective TEVAR, in this study. TEVAR was performed for degenerative aortic aneurysm (n = 43) or aortic dissection (n = 21), and the treatment length was 175 ± 52 mm. Brachial-ankle PWV (baPWV) was obtained before and 1 week after TEVAR. Univariable and multivariable logistic regression analyses were used to determine the predictors of increases in baPWV of ≥100 cm/sec after TEVAR.

RESULTS

baPWV increased from 1,851 ± 392 cm/sec to 2,047 ± 479 cm/sec, and the change in baPWV (ΔbaPWV) was 195 ± 339 cm/sec (95% confidence interval, 111-280). Thirty-seven patients (58%) had ΔbaPWV ≥100 cm/sec after TEVAR. In the multivariable analysis, in addition to Δheart rate and Δsystolic blood pressure, age (odds ratio, 1.21/year; 95% confidence interval, 1.05-1.40) and coronary artery disease (odds ratio, 12.0; 95% confidence interval, 1.20-121) were independent determinants of ΔbaPWV ≥100 cm/sec after TEVAR, whereas ΔbaPWV ≥100 cm/sec was not associated with treatment length or device type.

CONCLUSIONS

TEVAR was associated with PWV progression, especially in older patients with coronary artery disease, whereas treatment length or device type was not a predictor of PWV progression after TEVAR.

Aortic Remodeling and Clinical Outcomes Following Thoracic Endovascular Aortic Repair for Blunt Thoracic Aortic Injury

BACKGROUND

There is currently limited data assessing the long-term consequences of thoracic endovascular aortic repair (TEVAR) in otherwise healthy aortic segments remote from the site of endograft coverage. The aim of this study is to retrospectively evaluate aortic remodeling and long-term outcomes of blunt thoracic aortic injury (BTAI) patients treated with TEVAR. Our hypothesis is that significant changes to the aorta proximal to the graft-covered segment are suspected following TEVAR.

METHODS

An institutional review board-approved retrospective review of patients who underwent TEVAR for BTAI at a level I trauma center from 2004 to 2018 was performed. Forty-six patients were identified and of these, 32 patients with high-resolution computed tomographic angiography imaging follow-up were included in the study. Computed tomographic angiography measurements of aortic dimensions and branch vessels proximal, distal, and adjacent to the stent grafted segment were recorded preprocedure and postprocedure and analyzed. Primary device-related outcomes such as birdbeaking, mural thrombus, stent migration, and persistent endoleak were assessed. Patient outcomes including mortality, graft-related morbidity, and need for secondary interventions were also analyzed.

RESULTS

Mean follow-up of the selected patients in the study was 1.52 y (range, 0.06-8.0 y). Following TEVAR, the ascending aortic length increased significantly (mean 5.7 ± 4.6 mm, P < 0.001). The mean diameters of the ascending aorta (1.5 ± 1.5, P < 0.001 mm), the midaortic arch (1.3 ± 1.7 mm, P < 0.001), and proximal and the distal endograft landing zones (1.9 ± 2.1 mm and 2.2 ± 1.6 mm, respectively, P < 0.001) also increased significantly following TEVAR. Clinically relevant device-related outcomes occurred with the presence of endograft infolding and subsequent development of endograft mural thrombus (P < 0.001). The need for secondary intervention following TEVAR for BTAI was associated with endograft mural thrombus (P < 0.05).

CONCLUSIONS

TEVAR for BTAI causes significant geometric changes in the aorta proximal to the stented grafted segment of the aorta. Direct consequences of the graft at the stented segment includes mural thrombus development within the endograft which was associated with the need for secondary intervention. Although clinical significance is yet to be determined, post-TEVAR changes in aortic architecture warrant continued aortic surveillance following BTAI.

Aortic stiffness and related complications after endovascular repair of blunt thoracic aortic injury in young patients

Summary: Background: This study aimed to evaluate the changes in aortic stiffness in young patients undergoing thoracic endovascular aortic repair (TEVAR) after blunt thoracic aortic injury (TBAI) and to examine the associated cardiovascular complications during follow-up. Patients and methods: We included survivors of TBAI who underwent stent graft placement between November 2009 and November 2019 and gave their consent to participate. Patients with relevant cardiovascular risk factors, comorbidities with potential impact on arterial stiffness, and prior aortic surgical or endovascular interventions were excluded. Fourteen TEVAR patients prospectively underwent clinical and noninvasive examinations and morphological imaging (mean time of follow-up and duration of implanted stent graft: 5.3 ± 1.8 years; mean age: 35.1 ± 8.7 years) and were compared to 14 healthy controls (matched for sex, age, height, and body mass index) in order to evaluate aortic stiffness. During the follow-up examinations, we assessed the pulse wave velocity (PWV; m/s) and development of arterial hypertension or heart failure, as indicated by N-terminal pro-brain natriuretic peptide (NT-proBNP; pg/mL) levels and performed echocardiography. Results: A significant increase in PWV values was recorded in the TEVAR group (median = 10.1; interquartile range [IQR] = 8.9–11.6) compared to the healthy controls (median = 7.3; IQR = 6.7–8.4), with an increase in the rank mean PWV (+ 3.8; Mann-Whitney U test p < .001). NT-proBNP levels of patients after TEVAR did not vary significantly compared to those of healthy controls (Mann-Whitney U test, p = .154). After TEVAR, five patients developed arterial hypertension during the follow-up, and three of them exhibited diastolic dysfunction. Conclusions: In young patients, TEVAR after TBAI may cause adverse cardiovascular complications due to increased aortic stiffness; therefore, screening for arterial hypertension during follow-up is recommended.

Effect of endoprostheses on pulse wave velocity and its long-term outcomes after thoracic endovascular aortic repair

BACKGROUND

The purpose of this study was to evaluate the changes in pulse wave velocity and left ventricular dimensions in patients undergoing stent-graft treatment for aortic arch aneurysm.

METHODS

From July 2008 to February 2019, 86 patients underwent thoracic endovascular aortic repair of an aortic arch aneurysm. Changes in pulse wave velocity (PWV), echocardiogram findings, and long-term outcomes were compared between endoskeleton type (n = 60) and exoskeleton type stent-graft (n = 26).

RESULTS

There was no significant difference in patient demographics except for diabetes which was more observed in endoskeleton type (p = 0.017). There was a significant increase in PWV in exoskeleton type after surgery, which further progressed at a median follow-up of 32 months (before: 2047 cm/s vs. after: 2259 cm/s vs. follow-up: 2486 cm/s, p = 0.010, p = 0.017). No significant difference was observed in endoskeleton type (before: 1980 cm/s vs. after: 2058 cm/s, vs. follow-up: 2042 cm/s, p = 0.25, p = 0.34). Echocardiogram performed at a median period of 46.3 months, revealed a significant increase in left ventricular diastolic volume (LVDV) (before: 107.4 ± 20.6 ml vs. follow-up: 127.7 ± 27.5 ml, p = 0.003) and decrease in e' (before: 5.5 ± 1.78 cm/s vs. follow-up: 4.7 ± 1.72 cm/s, p = 0.012) in exoskeleton type, while no significant change was observed in endoskeleton type (LVDV: before: 102.6 ± 32.3 ml vs. follow-up: 96.9 ± 35.4 ml, p = 0.74; e': before: 4.4 ± 1.21 cm/s vs. follow-up: 4.8 ± 1.40 cm/s, p = 0.68). At the median period of 61.3 months, there was no significant difference in long-term mortality (p = 0.89). However, the endoskeleton type was associated with a lower incidence of a cardiac event (p = 0.034) and cerebrovascular event (p = 0.029).

CONCLUSION

Types of endoprosthesis might affect differently on physiological changes and its accommodated risk factors after surgery.

Enlargement Rate of the Ascending Aorta After Thoracic Endovascular Aortic Repair

It is known that the elasticity of the thoracic aorta decreases when it is covered with endografts. It remains to be clarified, however, whether endografts in the descending aorta affect aortic stiffening in the ascending aorta. We analyzed 46 patients who underwent thoracic endovascular aortic repair for descending thoracic aortic aneurysm between January 2008 and June 2016. We calculated the preoperative and postoperative rate of enlargement of the mid-ascending aorta using enhanced computed tomography. In 3 of these patients, we evaluated the peak systolic and time-averaged wall shear stress and relative cross-section area change at the level of the mid-ascending aorta using 4-dimensional flow magnetic resonance imaging. The postoperative rate of enlargement of the mid-ascending aorta was significantly greater than the preoperative rate (0.78 [0.31-1.38] mm/y vs 0.32 [0.12-0.60] mm/y; P < 0.001). In 2 of the 3 patients analyzed by 4-dimensional flow magnetic resonance imaging, the waveform of time-averaged wall shear stress had changed, and the relative cross-section area change decreased after thoracic endovascular aortic repair. There were no secondary surgical interventions for the ascending aorta after thoracic endovascular aortic repair. The rate of enlargement of the ascending aorta may be affected by the change in wall shear stress or aortic stiffening after thoracic endovascular aortic repair.

Changes in aortic pulse wave velocity of four thoracic aortic stent grafts in an ex vivo porcine model

Objectives

Thoracic endovascular aortic repair (TEVAR) has been shown to lead to increased aortic stiffness. The aim of this study was to investigate the effect of stent graft type and stent graft length on aortic stiffness in a controlled, experimental setting.

Methods

Twenty porcine thoracic aortas were connected to a pulsatile mock loop system. Intraluminal pressure was recorded at two sites in order to measure pulse wave velocity (PWV) for each aorta: before stent graft deployment (t₁); after deployment of a 100-mm long stent graft (t₂); and after distal extension through deployment of a second 100-mm long stent graft (t₃). Four different types of stent grafts (Conformable Gore^® TAG^® Device, Bolton Relay^® Device, Cook Zenith Alpha^™, and Medtronic Valiant^®) were evaluated.

Results

For the total cohort of 20 aortas, PWV increased by a mean 0.6 m/s or 8.9% of baseline PWV after deployment of a 100-mm proximal stent graft (P<0.001), and by a mean 1.4 m/s or 23.0% of baseline PWV after distal extension of the stent graft (P<0.001). Univariable regression analysis showed a significant correlation between aortic PWV and extent of stent graft coverage, (P<0.001), but no significant effect of baseline aortic length, baseline aortic PWV, or stent graft type on the percentual increase in PWV at t₂ or at t₃.

Conclusions

In this experimental set-up, aortic stiffness increased significantly after stent graft deployment with each of the four types of stent graft, with the increase in aortic stiffness depending on the extent of stent graft coverage.

Changes in Geometry and Cardiac Deformation of the Thoracic Aorta after Thoracic Endovascular Aortic Repair

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) has dramatically expanded treatment options for patients with thoracic aortic pathology. The interaction between endografts and the dynamic anatomy of the thoracic aorta is not well characterized for repetitive physiologic stressors and subsequent issues related to long-term durability. Through three-dimensional (3D) modeling we sought to quantify cardiac-induced aortic deformation before and after TEVAR to assess the impact of endografts on dynamic aortic anatomy.

METHODS

Eight patients with acute (n = 4) or chronic (n = 3) type B dissections, or chronic arch aneurysm (n = 1), underwent TEVAR with a single (n = 5) or multiple (n = 3) Gore C-TAG(s). Cardiac-resolved thoracic CT images were acquired pre- and post-TEVAR. 3D models of thoracic aorta and branch vessels were constructed in systole and diastole. Axial length, mean, and peak curvature of the ascending aorta, arch, and stented lumens were computed from the aortic lumen centerline, delineated with branch vessel landmarks. Cardiac-induced deformation was computed from mid-diastole to end-systole.

RESULTS

Pre-TEVAR, there were no significant cardiac-induced changes for aortic axial length or mean curvature. Post-TEVAR, the ascending aorta increased in axial length (2.7 ± 3.1%, P < 0.05) and decreased in mean curvature (0.38 ± 0.05 → 0.36 ± 0.05 cm^-1, P < 0.05) from diastole to systole. From pre- to post-TEVAR, axial length change increased in the ascending aorta (P < 0.02), mean curvature decreased in the arch and stented aorta (P < 0.03), and peak curvature decreased in the stented aorta (P < 0.05).

CONCLUSIONS

TEVAR for a range of indications not only causes direct geometric changes to the stented aorta but also results in dynamic changes to the ascending and stented aorta. In our cohort, endograft placement straightens the stented aorta and mutes cardiac-induced bending due to longitudinal stiffness. This is compensated by greater length and curvature changes from diastole to systole in the ascending aorta, relative to pre-TEVAR.

Effect of endoskeleton stent graft design on pulse wave velocity in patients undergoing endovascular repair of the aortic arch

PURPOSE

Pulse wave velocity (PWV), which measures vascular stiffness, is a powerful predictor of cardiovascular event. Treatment of aneurysms with endovascular prosthesis has been reported to increase PWV. The purpose of this study was to evaluate whether an endoskeleton stent graft design has less effect on PWV than the exoskeleton stent graft design.

METHODS

Between July 2008 and September 2016, 74 patients underwent endovascular treatment of aortic arch aneurysm in our institution. PWV before and after surgery were compared between those who underwent treatment with Najuta, an endoskeleton stent graft (n = 51), and those treated with other commercially available exoskeleton stent grafts (n = 23).

RESULTS

Preoperative PWV (endoskeleton: 2004 ± 379.2 cm/s vs. exoskeleton: 2083 ± 454.5 cm/s, p = 0.47) was similar between the two groups. Factors that were associated with preoperative PWV were age (r = 0.37, 95% CI 0.15-0.56, p = 0.002) and mean arterial pressure (r = 0.53, 95% CI 0.34-0.68, p < 0.001). There was a significant increase in PWV in patients treated by exoskeleton stent grafts (before: 2083 ± 454.5 cm/s vs. after: 2305 ± 479.7 cm/s, p = 0.023) while endoskeleton stent graft showed no change in PWV (before: 2003 ± 379.2 vs. after: 2010 ± 521.1, p = 0.56). In a multivariate analysis, mean arterial pressure (coef 17.5, 95% CI 6.48-28.59, p = 0.002) and exoskeleton stent graft (coef 359.4, 95% CI 89.36-629.43, p = 0.010) were independently associated with PWV after surgery.

CONCLUSIONS

Physiological changes after endovascular treatment should be considered including effect on vascular stiffness. Endoskeleton stent graft may provide aneurysm repair with minimum effect in PWV after surgery.