Intra-arterial Catheter Research Articles

Endovascular Repair in Patients with Axillary-Subclavian Arterial Trauma

Arterial trauma of the axillary subclavian segment carries considerable morbidity and mortality risks. Surgical approaches are challenging given the hidden trajectory of these vessels which has made the endovascular approach a valid -and potentially better- alternative for managing these injuries. We describe the incidence of relevant outcomes for patients with traumatic axillary and/or subclavian artery injury who underwent endovascular therapy at a tertiary care-university hospital over a 15-year period in Cali, Colombia. We conducted an incidence study based on clinical records that included patients aged 15 years or older with traumatic axillary subclavian arterial injury treated with endovascular therapy between 2008 and 2022. Vascular injuries caused by intra-arterial dialysis catheter insertion (iatrogenic) were excluded. We described clinical and imaging characteristics upon admission, perioperative findings, and the incidence of complications and in-hospital mortality, with accompanying 95% confidence intervals. We included 32 patients, 93.8% of whom were male, with a median (IQR) age of 30 (21-42) years. The type of trauma was penetrating in 75% of patients (62.5% corresponding to gunshot wounds) and blunt in 25%. Upon admission, 12 patients (37.5%) exhibited hard signs of vascular injury, and 20 patients (62.5%) exhibited soft signs. Fourteen patients (47%) had an Injury Severity Score (ISS) greater than 15 and 12 (37.5%) had hemodynamic instability. All but three patients (90.6%) suffered subclavian artery injury (right 48.3%, left 51.7%), while 12.9% had axillary artery injury (one patient with both vessels affected). Intraoperative complications happened in one patient (3.1%, 95%CI: 0.2%-18%). Pseudoaneurysms were identified in 11 patients (34.4%), thrombosis in 6 (18.8%), and dissection in 6 (18.8%). Three (9.4%) patients required hybrid management (endovascular therapy following conventional surgery). No cases of ischemia or amputation occurred. The length of hospital stay was 6 (3, 11.5) days. No cases of in-hospital mortality were reported (0%, 95% CI: 0.0-13.4%). Endovascular treatment in trauma is a minimally invasive technique with favorable clinical outcomes in patients with arterial trauma in the axillary-subclavian segment. This should be a viable therapeutic option for selected cases.

Effects of renal denervation on the incidence and severity of cardiovascular diseases.

Renal denervation (RDN) is a neuromodulation therapy performed in patients with hypertension using an intraarterial catheter. Recent randomized sham-controlled trials have shown that RDN has significant antihypertensive effects that last for more than 3 years. Based on this evidence, the US Food and Drug Administration has approved two devices, the ultrasound-based ReCor ParadiseTM RDN system and the radiofrequency-based Medtronic Symplicity SpyralTM RDN system, as adjunctive therapy for patients with refractory and uncontrolled hypertension. On the other hand, there have been no randomized sham-controlled prospective outcome trials on RDN, and the effects of RDN on cardiovascular events such as myocardial infarction, heart failure, and stroke have not been elucidated. This mini-review summarizes the latest findings focusing on the effects of RDN on organ protection and physiological function and symptoms in both preclinical and clinical studies. Furthermore, the feasibility of using blood pressure as surrogate marker for cardiovascular outcomes is discussed in the context of relevant clinical studies on RDN. A comprehensive understanding of the beneficial effects of RDN on the incidence and severity of cardiovascular diseases with their underlying mechanisms will enhance physicians' ability to incorporate RDN into clinical strategies to prevent cardiovascular events including myocardial infarction, heart failure, and stroke. This mini-review focuses on the effects of RDN on organ protection and physiological function and symptoms in preclinical and clinical studies. RDN is expected to reduce the onset and progression of cardiovascular diseases including myocardial infarction, heart failure, and stroke in clinical practice.LV left ventricular, LVEF left ventricular ejection fraction, VO2max maximal oxygen uptake, VT ventricular tachycardia, VF ventricular fibrillation, 6MWD 6-min walk distance, NT-proBNP N-terminal pro-B-type natriuretic peptide, NYHA New York Heart Association, BBB blood-brain barrier, BP blood pressure.

Indications for renal denervation in the treatment of hypertension.

Renal denervation (RDN) is a neuromodulation therapy performed using an intraarterial catheter in patients with hypertension. Recent randomized sham-operated controlled trials have shown that RDN has significant antihypertensive effects in patients with resistant, uncontrolled, and/or drug-naïve hypertension. Based on available evidence, the European Society of Hypertension 2023 guidelines include a Class II recommendation for the use of RDN in individuals with resistant and uncontrolled hypertension. The US Food and Drug Administration approved two devices, the ultrasound-based ReCor ParadiseTM RDN system and the radiofrequency-based Medtronic Symplicity SpyralTM RDN system, as adjunctive therapy for patients with resistant and uncontrolled hypertension. The indications for RDN and incorporation of RDN into clinical practice will grow as clinical evidence accumulates. This mini review summarizes latest findings focusing on the safety and effectiveness of RDN for treating hypertension in the absence and presence of antihypertensive drugs, and discusses the indications for RDN. This mini review focuses on the safety and effectiveness of RDN for treating hypertension in the absence and presence of antihypertensive drugs. The indications for RDN and incorporation of RDN into clinical practice will grow as clinical evidence accumulates and should be reviewed and updated.

Association between intra-arterial catheterization and mortality of acute heart failure patients without shock in ICU: A retrospective study

BackgroundAcute heart failure necessitates intensive care, and arterial catheterization is a commonly performed invasive procedure in the intensive care unit (ICU). We aimed to investigate the association between arterial catheterization and outcomes in acute heart failure patients without shock. MethodsWe utilized MIMIC-IV database records for acute heart failure patients at Beth Israel Deaconess Medical Center from 2008 to 2019. Employing doubly robust estimation, we examined the relationship between arterial catheterization and outcomes, including 28-day, 90-day, in-hospital mortality, and ICU-free days within 28 days. ResultsOf 6936 patients identified, 2078 met inclusion criteria; 347 underwent arterial catheterization during their ICU stay. We observed no significant difference in 28-day mortality (odds ratio [OR]: 0.61, 95 % confidence interval [CI]: 0.31–1.21, P = 0.155), though catheterization was associated with reduced in-hospital mortality (OR: 0.41, 95 % CI: 0.14–0.65, P = 0.02). No significant effects were observed on 90-day mortality or ICU-free days within 28 days. ConclusionOur findings suggest that arterial catheterization is not associated with 28- and 90-day mortality rates in acute heart failure patients without shock but is linked to lower in-hospital mortality. Additional research and consensus are required to determine the appropriate utilization of arterial catheterization in patients.

Impact of procedural handling on the physiological effects of alfaxalone anaesthesia in the ball python (Python regius)

To describe the cardiovascular changes following intramuscular (handled) and intravascular (undisturbed, via intraarterial catheter) alfaxalone administration, we studied 20 healthy ball pythons (Python regius) in a randomised, prospective study. The pythons were instrumented with occlusive arterial catheters to facilitate undisturbed, continuous monitoring of heart rate and blood pressure. Six pythons were administered intramuscular (IM) saline, followed by 20 mg/kg IM alfaxalone, and were manually restrained for both injections. Six pythons received intraarterial (IA) saline, followed by 10 mg/kg IA alfaxalone, and remained undisturbed for both injections. Arterial blood samples were taken at 0, 12 and 60 min post-injection, and heart rate and blood pressure were recorded for 60 min. The remaining eight snakes received 20 mg/kg IM or 10 mg/kg IA alfaxalone (n = 4 per treatment) and were not handled for intubation 10 min post-injection, to examine the effects of handling during anaesthesia. IM administration of 20 mg/kg alfaxalone or an equivalent volume of saline elicited a profound tachycardia and hypertension, which recovered to resting values after 20 min. However, when 10 mg/kg alfaxalone or saline were injected IA, mild hypotension and a lower magnitude tachycardia occurred. Arterial PCO2 and PO2, pH and lactate concentrations did not change following IA alfaxalone, but an acidosis was observed during IM alfaxalone anaesthesia. There were no significant changes in plasma catecholamines and corticosterone among treatments. Handling for injection and during anaesthesia associated with intubation significantly affects cardiovascular parameters, whereas alfaxalone per se only elicits minor changes in cardiovascular physiology.

Agreement between noninvasive oscillometric and invasive intra-arterial blood pressure in children with ruptured brain arteriovenous malformations

BackgroundDivergence between intra-arterial catheters blood pressure (ABP) and noninvasive oscillometry (NIBP) may affect the care of children with brain arteriovenous malformations (bAVMs). We described the agreement between ABP and NIBP in these children. MethodsWe conducted a retrospective review of patients admitted to the pediatric intensive care unit between 2017 and 2023 with bAVM rupture. Paired ABP and NIBP measurements were collected. Bland-Altman analyses were used to assess agreement. Correlation analysis was conducted between higher ABP and divergence between systolic BP (SBP) measurements. Hypertension was defined as mean arterial pressure (MAP) exceeding age-based 95th percentile. ResultsThirty-four patients with 1901 BP pairs were observed. Bias overall was acceptable, but standard deviation (SD) was high. The best agreement of MAP was in non-hypertensive (bias 1.23 mmHg, SD 8.03 mmHg) and radial arterial catheters (bias 1.83 mmHg, SD 9.08 mmHg) subgroups. Bias for SBP was higher in hypertension (10.98 mmHg) and in infratentorial bAVMs (7.42 mmHg), suggesting poorer agreement in these subgroups. There were significant correlations between intra-arterial MAP and SBP divergence (R = +0.346, p<.001) and between intra-arterial SBP and SBP divergence (R = +0.677, p<.001), suggesting divergence widens with higher BP. Around 25 % of measurement pairs diverged to where one measurement crossed the clinical threshold for treatment, while the other did not, with ABP being more frequently higher than NIBP. ConclusionsThere is good agreement between ABP and NIBP, particularly in non-hypertensive ranges and with radial arterial catheters. Measurements, however, diverge in hypertension. Further research must define age-based thresholds, validate methods of BP measurement, and determine the effect of BP reduction on outcomes in these children.

ROLE OF THE NURSE IN MANAGING INVASIVE BLOOD PRESSURE MONITORING

Abstract Introduction Arterial blood pressure (BP) monitoring is an invasive system for directly tracking and measuring BP and finds its use in critically ill patients who require continuous hemodynamic monitoring and frequent arterial blood test. [1] Invasive monitoring requires the use of sophisticated equipment and specific skills for its management, which influence the quality of care, including the introduction of a catheter inside the arterial vessel. [2] Intra–arterial catheterization is considered the Gold Standard for a direct measurement of BP. [3] Therefore, the objective of this work is to outline the role of the nurse in the management of invasive BP monitoring, with particular attention to the possibility of independently managing the positioning of the arterial cannula itself. Materials and Methods A review was performed on the management of invasive BP monitoring, with a particular focus on the role of the nurse in arterial cannula positioning. The Pubmed database was consulted. The search strategy involved the use of Mesh terms and free terms, including "Hemodynamic Monitoring" “Vascular Access Devices” “Critical Care Nursing” “Arterial cannulation”. The terms used were combined together using the Boolean operator “AND”. The Code of Conduct for the Nursing ProfessionsMand the National Collective Labor Agreement were also examinatedand, along with everyday practice of professionals in this field of action. Results There are no studies in literature that clearly outline the role of the different professional figures in the management of invasive BP monitoring and there are no clear references regarding who is responsible for positioning the arterial cannula. The development of continuing education programs in the area of clinical reasoning skills for hemodynamic monitoring should be more emphasized. Furthermore, we should focus more on improving practical skills for hemodynamic monitoring. [4] Conclusions Advanced skills need to be officially acknowledge to the expert professional by the institutions they belong to, which should contribute to training by creating accredited company courses. Not only to protect assisted people and the professional, but also in order to enhance their work and give it the right recognition. Subsequently, studies could be carried out to evaluate the effective reduction in latency times between non–invasive monitoring and invasive monitoring on critically ill patients, if managed by the nurse.

Can Currently Available Non-invasive Continuous Blood Pressure Monitors Replace Invasive Measurement With an Arterial Catheter?

Deviations from normal blood pressure (BP) during general anesthesia have been clearly linked to several adverse outcomes. Measuring BP accurately is therefore critically important for producing excellent outcomes in health care. Normal BP does not necessarily guarantee adequate organ perfusion however and adverse events have occurred even when BP seemed adequate. Invasive blood pressure monitoring has recently evolved beyond merely measuring BP. Arterial line-derived pulse contour analysis is used now to assess both cardiac output and stroke volume variation as indices of adequate intravascular volume. Confirmation of acceptable cardiac output with data derived from invasive intra-arterial catheters has become very important when managing high-risk patients. Newer devices that measure BP continuously and non-invasively in the digital arteries via a finger cuff have also become available. Many clinicians contemplate now if these new devices are ready to replace invasive monitoring with an arterial catheter. Unlike non-invasive devices, intra-arterial catheters allow frequent blood sampling. This makes it possible to assess vital parameters like pH, hemoglobin concentration, ionized calcium, potassium, glucose, and arterial partial pressure of oxygen and carbon dioxide frequently. Non-invasive continuous BP measurement has been found to be unreliable in critically ill patients, the elderly, and patients with calcified arteries. Pulse contour-derived estimates of cardiac output and stroke volume variation have been validated better with data derived from arterial lines than that from the newer finger cuff monitors. Significant advances have been recently made with non-invasive continuous BP monitors. Invasive monitoring with an arterial line however remains the gold standard for measuring BP and assessing pulse contour analysis-derived hemodynamic variables in critically ill patients. In the future, non-invasive continuous BP monitors will likely replace intermittent oscillometers in the operating room and the postoperative period. They will however not eliminate the need for arterial catheterization in critically ill patients.

Hemodynamic Monitoring In The Cardiac Surgical Patient: Comparison of Three Arterial Catheters

ObjectiveSystemic systolic (SAP) and mean (MAP) arterial pressure monitoring is the cornerstone in hemodynamic management of the cardiac surgical patient and the radial artery is the most common site of catheter placement. The present study compares three different arterial line procedures. It is hypothesized that a 20-G 12.7cm catheter inserted in the radial artery will be equal to 20-G 12.7cm angiocath placed in the brachial artery, and superior to a 20-G 5.0cm angiocath placed in the radial artery. DesignA prospective randomized control was performed. SettingSingle Academic University Hospital ParticipantsAdult patients ≥ 18 years old undergoing non-emergent cardiac surgery utilizing cardiopulmonary bypass. InterventionsAfter approval by the Rhode Island Hospital institutional review board, a randomized prospective control study to evaluate three different peripheral intra-arterial catheter systems was performed: 1) Radial Short (RS). 20-G 5cm catheter, 2) Radial Long (RL): 20-G 12cm catheter, 3) Brachial Long (BL): 20-G 12cm catheter. Measurements&ResultsGradients between central aortic and peripheral catheters (CA-P) were compared and analyzed prior to CPB, and 2 and 10 minutes after separation from CPB. The placement of femoral arterial lines, and administration of vasoactive medications were recorded. After exclusions 67 BL, 61 RL, and 66 RS patients were compared. Prior to CPB CA-P SAP and MAP gradients were not significant among the three groups. Two minutes after CPB the CA-P SAP gradient was significant for the RS group (p=0.005) and insignificant for BL (p=0.47) and RL (p=0.39). Two-group analysis reveal that CA-P SAP gradients are similar between BL and RL (p=0.84), both of which were superior to RS (p=0.02 and p=0.04 resp.). At 10 minutes after CPB, the CA-P SAP gradient for RS remained significant (p=0.004) and similar to the gradient at 2 minutes. The CA-P SAP gradients increased from 2 to 10 minutes for BL (p=0.13) and RL (p=0.06). Two minutes after CPB the CA-P MAP gradients are significant for BL(p=0.003), RL(p< 0.0001), and RS(p< 0.0001) groups. Two-group analysis reveal that the CA-P MAP gradients were lower for the BL group compared to RL (p=0.054) and RS (p< 0.05) groups. Ten minutes after CPB, the CA-P MAP gradients in the RL and RS groups remained significant (p< 0.0001) and both greater than the BL group (p=0.002). A femoral arterial line was placed more frequently in the RS group (8/66=12.1%), than RL group (3/61=4.9%), and the BL group (2/67=3.0%). Vasopressin was administered significantly more frequently in the RS group… ConclusionRegarding CA-P SAP gradients, the RL group performed equally to the BL group, both being superior to RS. Regarding CA-P MAP gradients BL was superior to RL and RS. Clinically, femoral line placement and vasopressin administration was less for the BL and RL groups when compared to the RS group. This study demonstrates the benefits of a long (12.7cm) 20 G angiocath placed in the radial artery.

Combined stent retriever angioplasty and continuous intra-arterial nimodipine infusion as salvage therapy for cerebral vasospasm and delayed cerebral ischemia after subarachnoid hemorrhage: illustrative case.

Delayed cerebral ischemia (DCI) and cerebral vasospasm (CV) are severe complications of spontaneous subarachnoid hemorrhage (SAH) contributing to an inferior outcome. Rescue therapies include intra-arterial balloon angioplasty and repetitive and finally continuous intra-arterial nimodipine infusion. In the presented case, a young female patient with fulminant refractory DCI and CV, despite induced hypertension and nimodipine application, was treated with three-vessel continuous intra-arterial infusion and additional repetitive angioplasty of the basilar and middle cerebral arteries using a stent retriever, leading to a good clinical outcome. Additional stent retriever dilatation to continuous intra-arterial nimodipine application in three vessel territories may represent a further escalation step in the rescue therapy for severe CV and DCI after SAH. Montreal Cognitive Assessment and SF-36 testing showed satisfactory results 3 months after initial treatment with intra-arterial nimodipine catheters in three vessel territory circulations and additional stent retriever vasodilation of severe CV. We report a unique rescue strategy involving implantation of an additional intra-arterial catheter into the vertebral artery and repetitive stent retriever dilatations of the middle cerebral and basilar arteries as an extra therapy for continuous intra-arterial nimodipine vaspospasmolytic therapy in three vessel territories, resulting in a very good clinical outcome.

Exploring a Novel Technique to Tackle the Shortage of Devices for Hepatic Arterial Infusion Chemotherapy: Early Results of an Alternate Approach for Percutaneous Arterial Port Catheter Placement.

Dedicated catheters for hepatic arterial infusion chemotherapy were removed from the market. The purpose of this study was to assess the results of a novel approach to overcome the shortage of dedicated catheters for hepatic arterial infusion chemotherapy in the treatment of colorectal cancer liver metastases. We retrospectively included patients who underwent a percutaneous placement of a hepatic intra-arterial port catheter in a single tertiary center from February 2021 to June 2022. We examined the patient baseline characteristics, technical features of the modified procedures, technical success rates, complications and oncological outcomes. Fourteen patients (median age: 60 years; q1 = 54; q3 = 70; range: 53-81 years) underwent 15 modified procedures. The main modification of our placement technique consisted of the use of an indwelling 5-Fr Vertebral catheter, on the tip of which we created a two-sided additional lateral hole. The catheter was connected to a pediatric port. The primary success rate was 100%, and the secondary success rate was 93.3%. There were two late major complications, graded IIIa according to the Clavien-Dindo classification. The median liver progression free survival was 6.1 months (q1 = 2.5; q3 = 7.2; range: 1.3-11.6). Our experience suggests that the derived utilization of the devices used routinely in interventional radiology provides an effective solution that can compensate for the shortage of dedicated devices.

A Preliminary Discussion on the Safety of Mild Therapeutic Hypothermia in Target Vessels after Endovascular Intervention in Acute Large Vessel Occlusion Cerebral Infarction

Introduction: The aim of this study was to discuss the safety of rapid administration of 4°C hypothermic normal saline into the occluded vessels using an intra-arterial catheter to induce mild hypothermia following endovascular thrombectomy in patients with acute large vessel occlusion cerebral infarction. Methods: We selected 78 patients with acute large vessel occlusion cerebral infarction who underwent endovascular thrombectomy in the Department of Neurology of our hospital from January 2020 to July 2022 and achieved TICI 2b recanalization. Result: Twenty-five patients were administered 500 mL of 4°C hypothermic normal saline in the occluded vessels at a rate of 25 mL/min to induce mild hypothermia. Twenty pairs of subjects conformed to strict matching and were finally included in the statistical analysis. The two groups of patients differed significantly in white blood cell count and percentage of neutrophils (p < 0.05); however, there were no significant differences in D-dimer, procalcitonin, and BNP levels. The two groups of patients did not differ significantly with respect to the incidence of the following indicators: upper gastrointestinal bleeding; pulmonary infection; venous thrombosis; vasospasms; seizures; and chills (p > 0.05). Conclusion: Mild therapeutic hypothermia in target vessels plus endovascular thrombectomy was shown to be safe in patients with acute large vessel occlusion cerebral infarction.

Association between intraoperative pulmonary artery pressure and cardiovascular complications after off-pump coronary artery bypass surgery: a single-center observational study

BackgroundThe impact of intraoperative pulmonary hemodynamics on prognosis after off-pump coronary artery bypass (OPCAB) surgery remains unknown. In this study, we examined the association between intraoperative vital signs and the development of major adverse cardiovascular events (MACE) during hospitalization or within 30 days postoperatively.MethodsThis retrospective study analyzed data from a university hospital. The study cohort comprised consecutive patients who underwent isolated OPCAB surgery between November 2013 and July 2021. We calculated the mean and coefficient of variation of vital signs obtained from the intra-arterial catheter, pulmonary artery catheter, and pulse oximeter. The optimal cut-off was defined as the receiver operating characteristic curve (ROC) with the largest Youden index (Youden index = sensitivity + specificity – 1). Multivariate logistic regression analysis ROC curves were used to adjust all baseline characteristics that yielded P values of < 0.05.ResultsIn total, 508 patients who underwent OPCAB surgery were analyzed. The mean patient age was 70.0 ± 9.7 years, and 399 (79%) were male. There were no patients with confirmed or suspected preoperative pulmonary hypertension. Postoperative MACE occurred in 32 patients (heart failure in 16, ischemic stroke in 16). The mean pulmonary artery pressure (PAP) was significantly higher in patients with than without MACE (19.3 ± 3.0 vs. 16.7 ± 3.4 mmHg, respectively; absolute difference, 2.6 mmHg; 95% confidence interval, 1.5 to 3.8). The area under the ROC curve of PAP for the prediction of MACE was 0.726 (95% confidence interval, 0.645 to 0.808). The optimal mean PAP cut-off was 18.8 mmHg, with a specificity of 75.8% and sensitivity of 62.5% for predicting MACE. After multivariate adjustments, high PAP remained an independent risk factor for MACE.ConclusionsOur findings provide the first evidence that intraoperative borderline pulmonary hypertension may affect the prognosis of patients undergoing OPCAB surgery. Future large-scale prospective studies are needed to verify the present findings.

Emerging topics on renal denervation in hypertension: anatomical and functional aspects of renal nerves.

Inappropriate sympathetic activation is closely associated with the development and progression of hypertension. Renal denervation (RDN) is a neuromodulation therapy performed using an intraarterial catheter in patients with hypertension. Recent randomized sham-operated controlled trials have shown that RDN has significant antihypertensive effects that last for at least 3 years. Based on this evidence, RDN is nearly ready for general clinical application. On the other hand, there are remaining issues to be addressed, including elucidation of the precise antihypertensive mechanisms of RDN, the appropriate endpoint of RDN during the procedure, and the association between reinnervation after RDN and the long-term effects of RDN. This mini review focuses on studies implicating anatomy of the renal nerves, which consist of afferent or efferent and sympathetic or parasympathetic nerves, the response of blood pressure to renal nerve stimulation, and reinnervation of renal nerves after RDN. A comprehensive understanding of the anatomical and functional aspects of the renal nerves and the antihypertensive mechanisms of RDN, including its long-term effects, will enhance our ability to incorporate RDN into strategies to treat hypertension in clinical practice. This mini review focuses on studies implicating anatomy of the renal nerves, which consist of afferent or efferent and sympathetic or parasympathetic nerves, the response of blood pressure to renal nerve stimulation, and reinnervation of renal nerves after renal denervation. Whether the ablation site is sympathetic dominant or parasympathetic dominant, and afferent dominant or efferent dominant, would in turn determine the final output of renal denervation. BP: blood pressure.

A Novel Triple-Bladder Cuff Method for Blood Pressure Estimation Based on Pulse Wave Dynamics in Brachial Artery: Theoretical and Experimental Analyses.

The objective of this study was to develop a novel triple-bladder cuff method for accurate and automated estimation of systolic (SBP) and diastolic (DBP) blood pressure and validate its reliability in animal experiments. The cuff is composed of three bladders each measured one-third the width of a conventional BP cuff, which are designed to measure oscillatory pulsation at the proximal, middle, and distal segments of the upper arm. This structure allows evaluation of the pulse wave propagation in the brachial artery under the cuff. SBP is estimated (SBPe) by detecting resumption of systolic arterial flow based on statistical similarity in oscillatory pulse traces between the proximal and distal segments. DBP is estimated (DBPe) based on the relation between pulse wave velocity and transmural pressure at diastole in the brachial artery. In 7 anesthetized goats, we compared SBPe and DBPe to reference SBP and DBP, respectively, measured by an intra-arterial catheter. BP was perturbed by infusing nitroprusside or noradrenaline. SBP correlated strongly with SBPe in each animal [mean coefficient of determination (R2) = 0.98 ± 0.01]. Mean ± standard deviation of errors between SBP and SBPe was 0.0 ± 4.9 mmHg. DBP correlated strongly with DBPe in each animal (R2 = 0.96 ± 0.03). Mean ± standard deviation of errors between DBP and DBPe was 0.0 ± 6.3 mmHg. This method estimates SBP and DBP with acceptable accuracy. Accurate and automated BP estimation by this method may potentially optimize antihypertensive treatment in patients with hypertension.

Non-invasive Assessment by B-Mode Ultrasound of Arterial Pulse Wave Intensity and Its Reduction During Ventricular Dysfunction.

Arterial pulse waves contain clinically useful information about cardiac performance, arterial stiffness and vessel tone. Here we describe a novel method for non-invasively assessing wave properties, based on measuring changes in blood flow velocity and arterial wall diameter during the cardiac cycle. Velocity and diameter were determined by tracking speckles in successive B-mode images acquired with an ultrafast scanner and plane-wave transmission. Blood speckle was separated from tissue by singular value decomposition and processed to correct biases in ultrasound imaging velocimetry. Results obtained in the rabbit aorta were compared with a conventional analysis based on blood velocity and pressure, employing measurements obtained with a clinical intra-arterial catheter system. This system had a poorer frequency response and greater lags but the pattern of net forward-traveling and backward-traveling waves was consistent between the two methods. Errors in wave speed were also similar in magnitude, and comparable reductions in wave intensity and delays in wave arrival were detected during ventricular dysfunction. The non-invasive method was applied to the carotid artery of a healthy human participant and gave a wave speed and patterns of wave intensity consistent with earlier measurements. The new system may have clinical utility in screening for heart failure.

Optical frequency domain reflectometry shape sensing using an extruded optical fiber triplet for intra-arterial guidance.

Intra-arterial catheter guidance is instrumental to the success of minimally invasive procedures, such as percutaneous transluminal angioplasty. However, traditional device tracking methods, such as electromagnetic or infrared sensors, exhibits drawbacks such as magnetic interference or line of sight requirements. In this work, shape sensing of bends of different curvatures and lengths is demonstrated both asynchronously and in real-time using optical frequency domain reflectometry (OFDR) with a polymer extruded optical fiber triplet with enhanced backscattering properties. Simulations on digital phantoms showed that reconstruction accuracy is of the order of the interrogator's spatial resolution (millimeters) with sensing lengths of less than 1 m and a high SNR.

Agreement of high-definition oscillometry at two cuff locations with invasively measured arterial blood pressures in anaesthetised cheetahs

ObjectivesTo evaluate the agreement between high-definition oscillometry (HDO) used on the metatarsus or tail base with invasive arterial blood pressures measured in the dorsal pedal artery in anaesthetised cheetahs. Study DesignProspective clinical study. AnimalsA group of 13 captive adult cheetahs. MethodsCheetahs were immobilised with medetomidine (32–45 μg kg–1) and tiletamine/zolazepam (0.93–1.39 mg kg–1) administered intramuscularly, and anaesthesia was maintained with either isoflurane in oxygen or continuous propofol infusion. Invasive blood pressure was measured via a 20 gauge intra-arterial catheter in the dorsal pedal artery in the metatarsus and used as a reference method for pressures simultaneously estimated using HDO on the contralateral metatarsus and tail base. Bland–Altman plots (for repeated measurements) and criteria defined by the American College of Veterinary Internal Medicine (ACVIM) were used to compare agreement according to the anatomical location of the cuff, the anaesthetic maintenance agent and magnitude of the blood pressure. ResultsA total of 147 paired measurements were obtained with HDO on the metatarsus and 135 on the tail. Agreement with invasive pressures was better when HDO was used on the tail (rather than on the metatarsus) with all ACVIM criteria being met. Mean bias (a positive bias meaning that HDO overestimated the invasively measured pressures) ± standard deviation of differences for systolic, diastolic and mean arterial pressures were –7.0 ± 13.9, 4.2 ±12.1 and 4.6 ±11.2 mmHg, respectively, for HDO on the tail, and –11.9 ±15.1, 2.8 ±16.5 and 2.1 ±13.2 mmHg, respectively, for HDO on the metatarsus. Agreement was better during isoflurane anaesthesia than propofol, and at lower blood pressures than at higher. Conclusions and clinical relevanceWhen used on the tail base of anaesthetised cheetahs, HDO met the ACVIM validation criteria for a noninvasive device, as compared to invasively measured pressures in the dorsal pedal artery.

Abstract C016: New treatment modality for pancreatic cancer-Vascular Targeted Photodynamic therapy with WST11 (Padeliporfin) combined with endovascular light delivery

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human malignancies. Early detection and surgical removal of PDAC, when the cancer is localized with no clinical evidence for systemic spread, may be curative but tumor spread into the vicinity of major blood vessels, e.g. superior mesenteric artery (SMA), can be lethal and therefore avoid surgery. Here we show that Vascular Targeted Photodynamic therapy (VTP) with WST11 in combination with immune modulating chemotherapeutic agents allows PDAC tumors ablation while preserving large normal vessels and tissues in animal models. New endovascular illumination system recently developed by our group (1) provides the light needed for such ablation with no damage to the SMA and complete remodeling of the surrounding normal tissue. Methods: Two orthotopic models of pancreatic cancer (KPC-Luc-mcherry and non-labeled KPC tumors (NL-KPC)) in C57B mice were subjected to VTP, alongside intraperitoneal gemzar (GEM) or cyclophosphamide (CTX) treatment. multiplex immunohistochemistry (mIHC) and single analyses using 10X Genomics platform of tumor were performed for resolving the key factors in the therapeutic process. Results: Comparing the KPC-Luc-mcherry with the NL-KPC tumor, we found that non labeled KPC has the typical morphology of human PDAC, immunologically cold and is highly aggressive compared with KPC-Luc-mcherry. WST11-VTP results in high cure rate (~50%) of animals bearing small KPC-Luc-mcherry tumors, larger tumors required combinations with metronomic administration of GEM. High rate of complete necrosis (95-100%) was achieved also with the non-labled PDAC tumors but prolonged disease- free survival required combination with CTX. The mechanism of action for both tumor models involves co-generation of oxygen and NO radicals through local photoexcitation of WST11, followed by iNOS consumption and vascular break down. Infiltration of immune cells alarmed by HMGB1 and other DAMPs leads to annihilation of residual cancer cells and prolonged anticancer immunity. The administration of CTX amplifies and prolonged the VTP oxidative stress. Conclusion: WST11-VTP combination with immune modulating chemotherapeutic agents administrations, activated by endovascular illumination through the SMA, may provide solution to the unmet need of early stage diagnosed PDAC patients. (1) Franz E. Boas et al, “Downstaging Locally Advanced Pancreatic Cancer To Resectability: Perivascular Ablation Using An Intra-arterial Balloon Laser Catheter In Pigs”, Abstract Archives of the RSNA, RSNA 2021,SDR-IR-13- “Redefining radiology” 11/29-12/4, 2021 Citation Format: Lilach Agemy, Keren Sasson, Tamar Yechezkel, Dina Priese, Yaniv Cohen, Zachary Zacks, Gil Stelzer, David P. Kelsen, Hooman Yarmohammadi, Alice C. Wei, Stephen B. Solomon, Avidgor Scherz. New treatment modality for pancreatic cancer-Vascular Targeted Photodynamic therapy with WST11 (Padeliporfin) combined with endovascular light delivery [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr C016.

Guidewire Perforation into the Oral Cavity from the Deep Lingual Artery During Retrograde Superselective Intra-Arterial Catheterization for a Tongue Cancer Patient

Guidewire Perforation into the Oral Cavity from the Deep Lingual Artery During Retrograde Superselective Intra-Arterial Catheterization for a Tongue Cancer Patient