[Human immunodeficiency virus and venous thromboembolism: Role of direct oral anticoagulants]

Nowadays, thanks to highly active antiretroviral therapy (HAART), human immunodeficiency virus (HIV) infection is transforming into a chronic disease. The life expectancy of people living with HIV (PWH) has increased, as well as their risk of developing several co-morbidities, in particular cardiovascular diseases. In addition, the incidence of venous thromboembolism (VTE) is increased in PWH with a 2 to 10 times higher incidence when compared to the general population. Over the last decade, direct oral anticoagulants (DOACs) have been widely used in the treatment and prevention of VTE and non-valvular atrial fibrillation. DOACs are characterized by a rapid onset of activity, a predictable response and a relatively wide therapeutic window. Nevertheless, drug interactions exist between HAART and DOACs, exposing PWH to a theoretically increased bleeding or thrombotic risk. DOACs are substrates of the transport protein P-glycoprotein and/or of isoforms of cytochromes P450 pathway, which can be affected by some antiretroviral drugs. Limited guidelines are available to assist physicians with the complexity of those drug-drug interactions. The aim of this paper is to provide an updated review on the evidence of the high risk of VTE in PWH and the place of DOAC therapy in this population.

Assessment of arterial damage in vascular Ehlers-Danlos syndrome: a retrospective multicentric cohort

Background

Vascular Ehlers-Danlos syndrome (vEDS) is a rare inherited connective tissue disorder due to pathogenic variants in the COL3A1 gene, leading to medium-size artery (MSA) dissection, aneurysm, and rupture with a poor prognosis. Conversely, aortic lesions are rarer and less investigated.

Purpose

To describe the association between the distribution of MSA and aortic lesions and the type of COL3A1 variants in a multicentric cohort of vEDS patients.

Methods

Analysis of the 330 vEDS adult patients from the French RaDiCO SEDVASC registry. At the time of the study, 87% were alive, 60.3% were index cases and 60.0% females. Median age at molecular diagnosis was 36 years (IQR 24.3–46.8). COL3A1 variants were identified using NGS and/or Sanger sequencing and classified according to their functional consequences: 80.6% dominant-negative (DN) and 19.4% leading to haplo-insufficiency (HI). Computed tomography angiography (CTA) was systematically performed during the initial work-up of patients. Carotid mechanics was also assessed by echotracking in a subgroup of 133 patients.

Results

Arterial lesion history was reported in 82.4% of the patients (N=272), with 227/272 patients (83.5%) having MSA lesions alone, 9 (3.3%) aortic lesions alone and 36 (13.2%) both. DN variant was associated with higher prevalence of arterial lesions than HI variant (P 0.044), especially on supra-aortic trunks and renal arteries (P 0.018 and P 0.0003 respectively). Importantly, the higher prevalence of aortic lesions observed in HI patients with arterial lesions versus DN patients (P 0.027) was not significantly different when adjusted for age (P 0.559). Carotid Young's modulus was lower in DN than HI patients (P 0.014), in association with the higher incidence of MSA lesions in this genotype group.

Conclusion

The prevalence of aortic lesions is not influenced by the COL3A1 genotype when adjusted for age. vEDS patients with DN variants have a higher frequency of MSA lesions especially in supra-aortic trunks which is associated with a lower carotid stiffness, suggesting a need for an optimal care for this subgroup of patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): French National Research Agency under the specific programme “Investments for the Future”, cohort grant-agreement ANR-l0-COHO-03-01

Celiprolol to prevent arterial events in patients with vascular Ehlers-Danlos and neither symptomatic nor silent arterial event. A retrospective cohort study from the French national reference center

Background

Vascular Ehlers-Danlos syndrome (vEDS) is a rare inherited connective tissue disorder, leading to mainly arterial complications, caused by COL3A1 pathogenic variations. Ong et al. (Lancet 2010) showed that the introduction of celiprolol significantly reduced arterial events in a predominantly symptomatic population on arterial level. We reported the benefit of full dose of Celiprolol in longitudinal study to prevent arterial events in Frank et al. (JACC 2019). To our knowledge, there is no data regarding the benefit of celiprolol in patients without any arterial event.

Purpose

The aim of this study was to assess the occurrence of arterial events during follow-up in vEDS patients without arterial event.

Methods

All patients – probands and relatives – with a pathogenic variation in COL3A1 diagnosed at the Referral Centre for Rare Vascular Diseases since 2001 and at least one arterial tree assessment were included. We then focused on vEDS patients without any arterial event. We retrospectively analyzed the duration of follow-up, the occurrence of arterial events during follow-up, and the introduction and dose of celiprolol, especially at the time of occurrence of an arterial event.

Results

Among the 230 patients included, 144 (63%) had at least one symptomatic arterial event, 44 (19%) had only silent arterial event and 67 (29%) had no arterial event at the first arterial tree assessment event. Patients with no arterial event were significantly younger at this visit compared with the two other groups with a median age of 23 vs. 38 and 39 years (silent and symptomatic) (p<0.05). Patients with no arterial event were more frequently relatives (73%) than probands (27%) (p<10–3). Celiprolol was introduced in 48 (72%) of the 67 patients with no arterial event after positive genetic diagnosis disclosure or during one of the outpatient visit. During follow-up, 22 patients had a first arterial event at a median age of 29 years: 16 (33%) were receiving celiprolol and 6 (32%) were not. But the median follow-up duration was 4 years for the 48 treated patients vs. 2 years for the 19 untreated patients (p=0.03).

Conclusions

Genetic testing of the relatives of probands with vEDS remains of utmost importance as one quarter presented with symptomatic arterial event and one fifth had silent arterial event at initial arterial tree assessment. For patients with no arterial event, those without celiprolol have a similar incidence of arterial events than those with celiprolol, however their follow-up duration was twice shorter suggesting a higher incidence rate or arterial event in the absence of celiprolol.

Funding Acknowledgement

Type of funding sources: None.

Elevated Lipoprotein(a) levels increase Major Adverse Limb Event

Background

High lipoprotein(a) levels are involved in the development of cardiovascular events, as particularly in myocardial infarction, stroke, and peripheral artery disease. Studies assessing prognostic values of lipoprotein(a) levels on the lower limbs are lacking.

Purpose

The aim of our study was to look after a relationship between the lipoprotein(a) level and the incidence of major adverse limb events (MALE) defined as major amputation, peripheral artery endovascular revascularization or peripheral artery bypass.

Methods

We included 16,513 patients with lipoprotein(a) measurements from our clinical information system. Normal lipoprotein(a) level was under 50 mg/dL and we defined: high lipoprotein(a) level as a lipoprotein(a) level between 50 mg/dL and 134 mg/dL and very high lipoprotein(a) level as a lipoprotein(a) levels over 134 mg/dL, i.e the 95th percentile in this cohort. Accelerated Failure Time models were used to assess the relationship between the lipoprotein(a) level and the incidence of MALE retrieved from the patient's electronic record during a median (interquartile range) follow-up of 3.74 (1.07; 7.30) years after the lipoprotein(a) measurement. MALE was defined as the occurrence of one of the following during follow-up: aortofemoral bypass surgery, limb bypass surgery, percutaneous transluminal angioplasty revascularization of the iliac, or infrainguinal arteries; or major amputation above the forefoot. Secondary outcomes included individual components of the primary

Results

Median lipoprotein(a) level was 24 mg/dL (10; 60), with 70.3%; 24.7%; and 5.0% within normal; high and very high lipoprotein(a) level respectively. The 1-year MALE incidence was 2.2% [95% CI: 1.96; 2.51]; 2.60% [95% CI: 2.09; 3.10] and 4.54% [95% CI: 3.08; 5.98] among the normal, high and very high lipoprotein(a) level patients respectively. High and very high lipoprotein(a) levels were independently associated with an increased risk of MALE (adjusted Accelerated Failure Time Exponential Estimate) 0.43 [95% CI: 0.24; 0.78], p=0.01 and 0.17 [95% CI: 0.07; 0.40], p<0.001, respectively.

Conclusion

In this large cohort of unselected real-world hospital inpatients, higher lipoprotein(a) levels were independently associated with an increased risk of MALE. Though, lipoprotein(a) measurement shall be taken into account not only to refine the cardiovascular risk but also the lower limb risk of revascularization or amputation.

Funding Acknowledgement

Type of funding sources: None.

Place of the Advanced Practice Registered Nurse within the vascular team: a qualitative study of vascular medicine physicians and nurses caring for patients with peripheral artery disease

Introduction

Advanced Practice Registered Nurses (APRNs) treat and diagnose diseases, counsel the public about health problems, manage chronic diseases, and participate in continuing education. In the cardiovascular field, Peripheral Arterial Disease (PAD), one of the manifestations of atherosclerotic cardiovascular disease, is archetypal in combining multiple cardiovascular risk factors (hypertension, hyperlipidemia, diabetes mellitus smoking). Vascular medicine faces the challenge of improving their care and quality of life, but some goals cannot be achieved with all patients. Patients with PAD should benefit from APRN care, but to date there is little published on the place of APRN in vascular medicine worldwide, and none in France.

Objective

It appeared important to us to assess the perception of their role by physicians and nurses in vascular medicine. As the status of APRN in France has only been enacted by law in 2018, we aim to investigate physicians and nurses working with patients suffering from PAD, to gather their opinions and draw the cooperation outlines these practitioners could have with an APRN.

Methods

Multicentre exploratory qualitative study by semi-directive interview conducted until data saturation and thematic analysis carried out with healthcare practitioners taking care of patients with PAD: 10 physicians working either in private practice setting or hospital setting or both, and 8 nurses in a vascular unit for hopsitalised patients.

Results

Three main themes emerged from responders' verbatims: a specific organization of vascular medicine with its inherent challenges, particularly regarding patients with PAD (specific psychosocial profile of patients, lack of therapeutic education, time, knowledge of non-specialist physicians, tedious follow-up outside hospitals, complex care trajectory, and lack of medical-surgical collaboration). Second, a role for APRN, particularly in consultation as part of patient follow-up, with expected benefits for the patient and the care team. The APRN is wanted to fill part of this gap. The expected benefits include a smoother care pathway and increased capacity for cardiovascular education and prevention, especially during consultations. Third, there are certain pitfalls that need to be clarified to integrate these new practitioners into the vascular teams already in place. In particular, the need to inform the vascular medicine teams about this new profession, and the indispensable presence of the conditions necessary for the development of a relationship of trust.

Conclusion

APRN could be the missing link in a Vascular team by creating a continuum in the care of patients with PAD, ensuring clinical assessment, nursing supervision, adverse event screening, and renewing drug prescriptions with the necessary adjustments, while ensuring an essential part of therapeutic education personalized to each PAD patient.

Funding Acknowledgement

Type of funding sources: None.

Evaluation of Takayasu's arteritis activity by ultrasound localization microscopy

Objectives

Use of sulphur hexafluoride microbubbles (MB) with ultrasound can provide arterial wall enhancement. The use of ultrafast imaging with MB super-localization offers the possibility of ultrasound localization microscopy (ULM) and thus a visualization of in vivo carotid vasa vasorum. We aim to perform in vivo Vasa vasorum imaging in the carotid wall in Takayasu's arteritis and to provide a correlation with the disease's activity.

Methods

Patients with Takayasu arteritis were consecutively included in the national referral centre. Assessment of activity was performed by NIH activity index, with measurement of biological inflammation, morphological evaluation by computed tomography (CT) angiography, and 18-fluorodeoxyglucose CT scan. Ultrafast ultrasound imaging was performed with a 7 MHz central frequency linear probe. A dedicated contrast imaging sequence (plane waves with 8 angles, frame rate 500 Hz, voltage 8 V, duration of 8 s), coupled with the intravenous injection of sulphur hexafluoride MB allow us to store the raw radio frequency data of the MB passage. After a pre-processing step to accumulate frames properly including a frames selection and a movement correction, the MB were localized then tracked, allowing reconstruction of the vasa vasorum. The inflammation was quantified through MB tracked and normalized for inter acquisition comparison.

Results

16 patients were included. 5 patients (median age 35.8 [24.5–46.0] years, 3 women) had active disease and 11 patients (37.2 [31.7–47.3] years, 9 women) had quiescent disease. The passage of MB allowed the visualisation of microvessels within the arterial wall for active cases. The number of MB detected per second in the wall was 118 [80–169] for active cases vs. 13 [10–15] for quiescent cases (p=0.0005).

Conclusion

ULM allows visualization of microvessels within the carotid wall, with significantly greater MB passage in active Takayasu arteritis. ULM provides for the first time a precise visualization in vivo of the vasa vasorum and gives access to quantification of the vascularity of the arterial wall.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Société française de cardiologie

Relationship between kalemia and intensive care unit admission or death in hospitalized COVID-19 patients: A cohort study

Background

Methods

Results

Conclusion

Safety and efficacy of low-dose PI3K inhibitor taselisib in adult patients with CLOVES and Klippel-Trenaunay syndrome (KTS): the TOTEM trial, a phase 1/2 multicenter, open-label, single-arm study

PURPOSE

PIK3CA pathogenic variants in the PIK3CA-related overgrowth spectrum (PROS) activate phosphoinositide 3-kinase signaling, providing a rationale for targeted therapy, but no drug has proven efficacy and safety in this population. Our aim was to establish the six-month tolerability and efficacy of low-dose taselisib, a selective class I PI3K inhibitor, in PROS patients.

METHODS

Patients over 16 years with PROS and PIK3CA pathogenic variants were included in a phase IB/IIA multicenter, open-label single-arm trial (six patients at 1 mg/day of taselisib, then 24 at 2 mg/day). The primary outcome was the occurrence of dose limiting toxicity (DLT). Efficacy outcomes were the relative changes after treatment of (1) tissue volume at affected and unaffected sites, both clinically and on imaging; (2) cutaneous vascular outcomes when relevant; (3) biologic parameters; (4) quality of life; and (5) patient-reported outcomes.

RESULTS

Among 19 enrolled patients, 2 experienced a DLT (enteritis and pachymeningitis) leading to early trial termination (17 treated, 10 completed the study). No serious adverse reaction occurred in the 1 mg cohort (n = 6). No significant reduction in affected tissue volume was observed (mean -4.2%; p = 0.81; SD 14.01). Thirteen (76.4%) participants reported clinical improvement (pain reduction, chronic bleeding resolution, functional improvement).

CONCLUSION

Despite functional improvement, the safety profile of low-dose taselisib precludes its long-term use.

Carotid plaque vulnerability assessed by combined shear wave elastography and ultrafast doppler compared to histology: the UF-plaque study

Purpose

New biomarkers are needed to assess the vulnerability of carotid plaque to guide carotid surgery decision. Ultrafast Ultrasound Imaging (UUI) provides an estimation of plaque stiffness by Shear Wave Elastography (SWE) and the quantification of wall shear stress (WSS) by ultrafast Doppler. We aimed at evaluating the plaque stiffness and WSS applied on the plaque as potential biomarkers of plaque vulnerability.

Methods

Patients were referred for carotid endarterectomy because of symptomatic or asymptomatic carotid stenosis. Their plaques were evaluated by UUI within 48 hours before surgery. For each plaque, WSS and SWE were obtained on a longitudinal view at the stenosis. After endarterectomy, gross analysis and histology were performed on each removed plaque.

Results

46 plaques with SWE data and 29 with WSS data were analysed. Histological analysis revealed 29 vulnerable and 17 stable plaques. Analysis of the Gray Scale Median by B mode, mean and standard deviation of stiffness by SWE were not helpful in identifying vulnerable plaques. Figure 1 presents the SWE acquisition on one plaque (A) and the distribution of plaque's stiffness average over all plaques showing the 4 ranges of stiffness (B). SWE analysis revealed that the percentage of stiffness range of [3–5] m/s was significantly increased in vulnerable plaques (p=0.048) (Figure 2A). WSS alone showed no significant difference between stable and vulnerable plaques regardless of which segment of the plaque was analysed. A multiparametric score using maximal WSS at the peak of the plaque associated with SWE texture analysis parameters was created by a stepwise analysis, leading to a score with a sensitivity of 80% and a specificity of 78%. The ROC curve of this score found an AUC of 0.85 (Figure 2B).

Conclusions

Multiparameter scoring including plaque stiffness and flow analysis using ultrafast ultrasound imaging allows an effective identification of histologically vulnerable carotid plaques.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Fédération Française de cardiologieSociété Française de Cardiologie Figure 1Figure 2

Ergotism with acute limb ischemia, provoked by HIV protease inhibitors interaction with ergotamine, rescued by multisite transluminal balloon angioplasty

Acute limb ischemia induced by arterial vasospasm remains an exceptional situation, favoured by the use of arterial vasoconstrictors. The risk of these substances is largely underestimated in the general population, especially with the co-administration of strong cytochrome inhibitors like human immunodeficiency virus (HIV) protease inhibitors. A 33-year-old woman, who used to take dihydroergotamine for orthostatic hypotension, was prescribed a post-exposure HIV prophylaxis including lopinavir and ritonavir. One day later, she presented an acute bilateral limb ischemia with a sudden pain in both calves, initially while walking and then at rest with bilateral ischemic toes. Angiography confirmed diffuse arterial vasospasm of the lower limb arteries. A first-line therapy with isosorbide dinitrate and amlodipine was ineffective, with rapid clinical worsening. A combination of intra-arterial injections and intra-venous infusions of vasodilators, transluminal balloon angioplasty and bilateral 4-Compartment fasciotomies permitted rapid improvement and finally resulted in both lower limbs rescue. This case and literature review illustrate ergotism due to ergotamine overdose after taking HIV protease inhibitors. It also demonstrates the benefit of an interventional procedure besides medical therapy with vasodilators in severe arterial vasospasm. All along the lower limb arterial tree, transluminal balloon angioplasty restored the blood flow, without vasospasm recurrence. CONCLUSION: In case of ergotism with acute lower limbs ischemia, combining medical vasodilator therapy with interventional procedure can restore the arterial blood flow, thus allowing to save lower limbs.

Respiratory mechanics and gas exchanges in the early course of COVID-19 ARDS: a hypothesis-generating study

Rationale

COVID-19 ARDS could differ from typical forms of the syndrome.

Objective

Pulmonary microvascular injury and thrombosis are increasingly reported as constitutive features of COVID-19 respiratory failure. Our aim was to study pulmonary mechanics and gas exchanges in COVID-2019 ARDS patients studied early after initiating protective invasive mechanical ventilation, seeking after corresponding pathophysiological and biological characteristics.

Methods

Between March 22 and March 30, 2020 respiratory mechanics, gas exchanges, circulating endothelial cells (CEC) as markers of endothelial damage, and D-dimers were studied in 22 moderate-to-severe COVID-19 ARDS patients, 1 [1–4] day after intubation (median [IQR]).

Measurements and main results

Thirteen moderate and 9 severe COVID-19 ARDS patients were studied after initiation of high PEEP protective mechanical ventilation. We observed moderately decreased respiratory system compliance: 39.5 [33.1–44.7] mL/cmH₂O and end-expiratory lung volume: 2100 [1721–2434] mL. Gas exchanges were characterized by hypercapnia 55 [44–62] mmHg, high physiological dead-space (V_D/V_T): 75 [69–85.5] % and ventilatory ratio (VR): 2.9 [2.2–3.4]. V_D/V_T and VR were significantly correlated: r² = 0.24, p = 0.014. No pulmonary embolism was suspected at the time of measurements. CECs and D-dimers were elevated as compared to normal values: 24 [12–46] cells per mL and 1483 [999–2217] ng/mL, respectively.

Conclusions

We observed early in the course of COVID-19 ARDS high V_D/V_T in association with biological markers of endothelial damage and thrombosis. High V_D/V_T can be explained by high PEEP settings and added instrumental dead space, with a possible associated role of COVID-19-triggered pulmonary microvascular endothelial damage and microthrombotic process.

SAT0244 PROGNOSIS OF LARGE VESSEL INVOLVEMENT IN LARGE VESSEL VASCULITIS

Background:

Giant cell arteritis (GCA) and Takayasu arteritis (TAK) are the two main forms of large vessels vasculitis (LVV). Vessel inflammation leads to aneurysms, wall thickening, stenosis, and, in some cases, complete occlusion of the artery. Due to the wide variation in the course of LVV, predicting outcome is challenging. To our knowledge, data regarding prognosis factors of LVI in LVV patients and comparison of outcome of LVI in GCA and TAK are lacking. An early identification of patients with higher mortality could help to prevent deaths and vascular complications.

Objectives:

To assess prognosis factors and outcome of large vessel involvement (LVI) in large vessels vasculitis (LVV) patients.

Methods:

Retrospective multicenter study of characteristics and outcomes of 417 patients with LVI including 299 Takayasu arteritis (TAK) and 118 Giant cell arteritis (GCA-LVI) were analyzed. Logistic regression analysis assessed prognosis factors in LVV patients. Outcome of LVI among TAK and GCA-LVI patients (ischemic complications, aneurysms complications, relapses and revascularization) were assessed.

Results:

In multivariable analysis, stroke/transient ischemic attack [HR: 3.63 (1.46 - 9.04), p=0.006] was independently associated with vascular complications in LVV. The 10-years aneurysm free survival was significantly lower [67% (48 – 93) vs 89% (84 – 95), p=0.02] in GCA-LVI compare to TAK patients. The 5-years relapse free survival was significantly lower [47% (37 – 60) vs 69% (63 – 75), p<0.001,] in GCA-LVI compare to TAK patients. The 10-years revascularization free survival was significantly lower [55% (48 – 64) vs 76% (59 – 99), p<0.001] in TAK compare to GCA-LVI patients. After a median follow-up of 5 years, 16 (5.4%) TAK and 7 (5.9%) GCA-LVI patients died, mainly of aneurysm (26%) and ischemic complications (26%).

Conclusion:

This large nationwide cohort of LVI provided prognosis factors of vascular complications in LVV patients. TAK and GCA-LVI have different long-term outcome in term of aneurysm development, relapse and revascularization.

Disclosure of Interests:

None declared

3041Wall shear stress measurement by ultrafast vector flow imaging for atherosclerotic carotid stenosis

Background

Carotid plaque vulnerability assessment is an important factor in guiding the decision to treat significant carotid stenosis. Ultrafast Ultrasound Imaging (UF) offers the possibility of evaluating local flow velocities over an entire 2D image, allowing access to velocity measurements in contact with the arterial wall and to measure the wall shear stress (WSS).

Purpose

To evaluate the feasibility of WSS measurement in a prospective series of patients with carotid stenosis.

Methods

A 7.5 MHz linear probe of an Aixplorer scanner was used. UF acquisitions had 3 tilted plane waves transmits (−10; 0; 10°) and an effective frame rate of 5000Hz. We evaluated the flow velocity in 5 areas of the carotid wall: common carotid artery (1), plaque ascent (2), plaque peak (3), plaque descent (4), internal carotid artery (5) (Figure). WSS was computed with the vector field speed using the following formula, WSS=μ·δn·v with v the blood velocity, n the normal vector to the vessel wall and μ, the blood viscosity, calculated from the hematocrit value for each patient. WSS measurement method was first validated using a laminar flow phantom and known viscosity. And then, 33 patients were then prospectively evaluated, with a median carotid stenosis degree of 80% [75–85].

Results

Significant correlation was found between in vitro measurement and the theoretical WSS values (R2=0.95; p<0.001).In patients,the maximum WSS value over the cardiac cycle follows the shape of the plaque with an increase during the ascend, reaching its maximum value of 3.57 Pa [2.47–4.45] at the peak of the plaque, and a fall after passing the peak (0.99 Pa [0.8–1.32]) lower than the WSS values in the non-stenotic areas (1.55 Pa [1.13–1.90] for the common carotid artery) (Table).

Table 1 Wall's area Wall shear stress (Pa) Min Max Delta 1. Common carotid artery 0.14 [0.05–0.27] 1.55 [1.13–1.90] 0.73 [0.55–0.96] 2. Plaque's ascent 0.39 [0.24–0.59] 2.63 [1.89–3.28] 1.20 [0.89–1.79] 3. Plaque's peak 0.60 [0.32–0.89] 3.57 [2.47–4.45] 1.78 [1.44–2.46] 4. Plaque's descent 0.16 [0.13–0.22] 0.99 [0.80–1.32] 0.52 [0.34–0.73] 5. Internal carotid artery 0.17 [0.13–0.35] 1.37 [1.04–1.75] 0.72 [0.50–0.87] Results are median [25th–75th percentile].

Figure 1

Conclusion

UF provide reliable WSS values. High WSS was present at the peak of the plaque, whereas lowest WSS values were found at the post-stenotic zone. WSS evaluation may help to better characterize the carotid plaque vulnerability.

P2765Efficacy of venous recanalization by noninvasive pulsed cavitational ultrasound therapy on swine model of acute deep venous thrombosis

Background

Post thrombotic syndrome is a frequent complication of deep venous thrombosis and is associated with high morbidity and hospitalization. Treatments currently available are invasive, involve use of endovenous procedures with stents and balloons, and frequently require general anesthesia. Pulsed cavitational ultrasound therapy (PCUT) emerged recently as a new technique to destroy remotely soft tissue. We recently demonstrated that PCUT was able to recanalize non-invasively in in vitro model of acute venous thrombosis (human blood clot).

Purpose

We aim to test the safety and efficacy of venous recanalization by noninvasive PCUT in vivo swine model of acute venous thrombosis.

Methods

All the experiments were performed on White large X Landrace swine. We induced an acute femoral deep venous thrombosis by using occlusive balloons introduced from jugular and popliteal vein combined with local injection of 50 IU of human thrombin. A 3 cm length occlusive thrombosis was obtained after 2 hours. Swines were divided in three groups: one with PCUT without follow-up (n=11), one with PCUT and follow-up at 14 days (n=8), and a control group also followed for 14 days (n=5). Acutely and during the follow up all swines received curative anticoagulation. To achieve PCUT, a 2.25 MHz transducer centered by a linear probe was used and cavitation was obtained in the center of the vein (Figure). After manual determination of thrombus location, a robotic arm was used to automatically move the transducer along the thrombus. Effectiveness of recanalization was evaluated by echo-Doppler and phlebography. Safety was assessed by Doppler ultrasound of the insonified area (artery, veins and surrounding tissue) and by histological analysis (local femoral vein and artery and lungs for pulmonary embolism).

Results

Among the 24 swines, we obtained 22 occlusive venous thromboses and 2 partial. The median length of the thrombus was 26±4.4 mm with vein diameter of 8.5±1.6 mm. Acutely, thrombosis recanalization was systematically obtained among the 19 swine with PCUT with median treatment duration of 33 minutes with residual diameter of 2.9±0.9 mm. No extravasation of contrast material or hematoma was observed after the therapy. After a 14-day follow-up, 75% of recanalisation remain permeable vs. 0% of vein permeable in the no therapy group (p=0.008). Residual diameter was 2.6±1.2 mm, which correspond to 50% of the venous diameter. No vein or artery damage and no embolism or pulmonary infarction was observed in all pigs.

Figure 1

Conclusion

We have demonstrated in vivo the safety and the efficacy of PCUT for non-invasive venous recanalization, persistent after 2 weeks.

Acknowledgement/Funding

French society of cardiology

P3110Tyrosine kinase inhibitor nilotinib increases atherosclerosis burden in ApoE knock-out mice

Background

In 2001, imatinib, the 1st generation tyrosine kinase inhibitor (TKI), dramatically improved the treatment and survival of the patients with chronic myeloid leukemia (CML). However, the emergence of imatinib-resistant patients led to the development of 2nd generation TKIs. Nilotinib demonstrated increased efficacy to control CML disease over imatinib and is now recommended as first-line therapy. But arterial occlusive adverse events (AOE) occurs in patients treated with nilotinib and not with imatinib. Mechanisms leading to AOE with nilotinib is not well understood. AOE are dominated by ischemic heart disease and lower extremity arterial disease. Moreover, we demonstrated that CML patients with cardiovascular risk factors are at high risk to rapidly develop AOE with nilotinib.

Purpose

To evaluate the impact of nilotinib in a pre-clinical model of atherosclerosis.

Methods

ApoE Knock-Out mice (8-week-old) were treated with either placebo (N=10), imatinib (IMA) 200mg/kg/day (N=10) or nilotinib (NILO) 100mg/kg/day (N=10) by daily feeding and a high-fat diet for 12 weeks. Heart and aorta were harvested after sacrifice, for histology staining and immunochemistry. Splenocytes were cultured from collected spleens, and Interleukin (IL) 12p70 and IL10 measured by ELISA.

Results

Mice treated with nilotinib showed an increase of atherosclerotic plaque size at the aortic sinus level: 462.1x103 μm2 vs. 344.4x103 μm2 with imatinib or 394.9x103 μm2 with placebo (p<0.05) and at the thoracoabdominal aorta level (p<0.05). Plaques had greater infiltration of macrophages: 33.0±3.4% with nilotinib vs. 7.3±1.3% with imatinib and 12.6±1.1% with placebo (p<0.001) and a larger necrotic nucleus 33.0±3.4% with nilotinib vs. 7.3±1.3% with imatinib or 12.6±1.1% with placebo (p<0.001). Nilotinib modulated the systemic immune response by increasing IL-12p70 and by decreasing IL-10 production by splenocytes after stimulation by LPS-IFNγ whereas IL10 increase was observed with imatinib.

Plaque size (aortic sinus)

Conclusion

Nilotinib has a pro-atherogenic effect in a pre-clinical model of atherosclerosis and increases the monocyte/macrophage pro-inflammatory response. Further experiments are required to identify pathways activated by nilotinib.

P1823Aortic walls elastic properties assessment with ultrafast ultrasound imaging in case of bicuspid aortic valve

Background

Magnetic resonance imaging allows evaluation of aortic stiffness by the maximum rate of systolic distension (MRSD) a new prognosis factor of aortic dilatation in patients with bicuspid aortic valve (BAV). MRSD requires a continuous monitoring of the aortic diameter during the cardiac cycle, not accessible to conventional echocardiography contrary to ultrafast ultrasound imaging (UF).

Purpose

To develop specific aortic sequences in ultrafast ultrasound imaging (UF) to provide access to the aortic MRSD

Methods

Tissue Doppler allowed a precise estimation of the movement of each wall and the fine variation of the aortic diameter. To automatically track the anterior and posterior aortic walls during the cardiac cycle, we developed in the laboratory a specific interface (Figure). MRSD was the maximum of the derivative of the diameter chande over time. To assess this new technique, 24 patients (10 BAV patients and 14 controls, mean age 45.8 vs. 40.7 years, p=0.464, respectively) were consecutively included at a reference center for BAV. The ascending aorta was evaluated at the sinus of Valsalva, the tubular aorta and the aortic arch with a phased array probe (Supersonic Imagine) and dedicated sequences at 2000 frames/s.

Results

The lab-made interface allowed to track the aortic diameter and to calculate the MRSD from the UF acquisitions for each patient. We found lower MRSD at the sinus of Valsalva in case of BAV in accordance with previously demonstrated higher stiffness at this segment by our team (Table).

Table 1. UF Aortic parameters for BAV patients and controls BAV patients Controls p (Mann Whitney) Sinus of Valsalva Diameter (mm) 26.2 [22.4–32.5] 27.09 [23.5–29.5] 0.796 MRSD (s–1) 1.05 [0.73–1.19] 1.51 [1.28–1.99] 0.023 Tubular ascending aorta Diameter 31.4 [29.4–32.2] 28.9 [22.6–31.5] 0.328 MRSD 0.94 [0.59–1.27] 1.09 [0.87–1.41] 0.353 Aortic arch Diameter 24.2 [23.7–24.8] 24.2 [18.9–24.5] 0.673 MRSD 0.57 [0.35–1.07] 0.85 [0.76–1.02] 0.257 Results are median [25th–75th percentile].

Figure 1

Conclusion

UF allows evaluation of aortic stiffness by MRSD using dedicated sequence and interface. As echocardiography, UF is easily accessible and therefore deserves attention from cardiologists taking care of BAV patients to evaluate the segmental aortic remodeling associated with BAV.

Correction to: Percutaneous Deep Venous Arterialization for Severe Critical Limb Ischemia in Patients With No Option of Revascularization: Early Experience From Two European Centers

The fifth author's name was incorrectly published as "M. Messas". The correct name is "E. Messas". The original article has been corrected.

[Recanalization procedure of the common femoral vein following iatrogenic femoral chronic occlusion: 3 cases]

Common femoral vein occlusion (CFVO) is frequently found in patients with chronic venous insufficiency. The iatrogenic form, secondary to either central catheter or surgery, is very rare but highly symptomatic. Classical compression therapy barely improves the clinical status of these patients, making them suitable candidates for an interventional procedure for venous recanalization.

METHODS

We report here three consecutive cases of iatrogenic CFVO referred to our outpatient clinic because the disease had an impact on daily life activities. We detail the recanalization procedure, the Doppler control and the short-term outcome.

RESULTS

In each case, endovascular recanalization required rigid material (rigid guide or Colapinto needle) to cross the fibrous adhesions before angioplasty could be performed with stenting. The procedure required two attempts in each case, underlining its complexity, but eventually enabled effective recanalization. No major complication occurred per- or post-procedure. One month later, a duplex Doppler control confirmed the permeability of the common femoral vein. The patients had experienced rapid and significant symptom improvement.

CONCLUSION

Patients suffering from severe chronic venous insufficiency caused by iatrogenic CFVO can benefit from endovascular recanalization. Although these procedures may be complex due to the extensive fibrosis at the Scarpa and require specialized equipment, no major complications were observed. Patency of the recanalization persisted at least one month after the procedure. Symptom relief was good.

[Takayasu arteritis]

Takayasu arteritis is a chronic inflammatory vasculitis of unknown origin affecting large vessels, predominantly the aorta and its main branches. Vessel inflammation leads to wall thickening, fibrosis, and stenosis. The lesions are often asymptomatic leading to limb numbness, transient ischemic attack, cardiovascular event and renovascular hypertension. Treatment is based on corticosteroids, immunosuppressant and biologics if necessary. Endovascular treatment and open-surgery can be useful for end-organ ischemia relief.

[Distal revascularization in diabetic patients with chronic limb ischemia]

Diabetes mellitus is an independent risk factor for peripheral artery disease. Life expectancy is 41 months for diabetic patients with an ischemic ulcer. The characteristics of diabetic arteriopathy make its treatment more difficult than in non-diabetic patients. Few data are available about the surgical treatment of arteriopathy in diabetic patients (including angioplasty or bypass), especially in case of distal arteriopathy. The choice of the procedure depends on multiple factors such as the disease localization, its extent, distal blood flow and vascular disease-related surgical risk. The principal aim of revascularisation is to restore direct flow to the foot in order to ensure wound healing and limb salvage. With percutaneous endoluminal angioplasty, limb salvage can be achieved in more than 80% of patients at 1-3 years. The percutaneous procedure is less invasive than open surgery, there are fewer complications, and morbidity and mortality rates are reduced; moreover, a second procedure remains possible in the future. With bypass surgery, the rate of limb salvage exceeds 80% at five years. Nevertheless, peri-operative mortality reaches 3% and arterial anatomy, patient-related risks factors or venous graft availability may be limitations. New endovascular techniques especially designed for the distal arteries of the lower limbs enable very distal revascularization with morbidity and mortality rates lower than with surgery.