Intra-cardiac motion detection catheter for the early identification of acute pericardial tamponade during invasive cardiac procedures

Objectives

To develop and test an intra-cardiac catheter fitted with accelerometers to detect acute pericardial effusion prior to the onset of hemodynamic compromise.

Background

Early detection of an evolving pericardial effusion is critical in ensuring timely treatment. We hypothesized that the reduction in movement of the lateral heart border present in developing pericardial effusions could be quantified by positioning an accelerometer in a lateral cardiac structure.

Methods

A "motion detection" catheter was created by implanting a 3-axis accelerometer at the distal tip of a cardiac catheter. The pericardial space of 5 adult sheep was percutaneously accessed, and pericardial tamponade was created by infusion of normal saline. The motion detection catheter was positioned in the coronary sinus. Intracardiac echocardiography was used to confirm successful creation of pericardial effusion and hemodynamic parameters were collected.

Results

Statistically significant reduction in acceleration from baseline was detected after infusion of only 40 ml of normal saline (p < 0.05, ANOVA). In comparison, clinically significant change in systolic blood pressure (defined as >10% drop in baseline systolic blood pressure) occurred after infusion of 80 ml of normal saline (107 ± 22 mmHg vs. 90 ± 12 mmHg p = 0.97, ANOVA), and statistically significant change was recorded only after infusion of 200 ml (107 ± 22 mmHg vs. 64 ± 5 mmHg, p < 0.05, ANOVA).

Conclusions

An intra-cardiac motion detection catheter is highly sensitive in identifying acute cardiac tamponade prior to clinically and statistically significant changes in systolic blood pressure, allowing for early detection and treatment of this potentially life-threatening complication of all modern percutaneous cardiac interventions.

Performance of the Wingman catheter in peripheral artery chronic total occlusions: Short-term results from the international Wing-It trial

OBJECTIVES

To determine the safety and effectiveness of a peripheral artery chronic total occlusion (CTO) crossing catheter following failed crossing attempts with standard guidewires.

BACKGROUND

CTO crossing remains a challenge during peripheral artery interventions.

METHODS

In this prospective, international, single-arm study, patients with a peripheral artery CTO that was uncrossable with standard guidewires were treated with a crossing catheter (Wingman, Reflow Medical). The primary efficacy endpoint of CTO crossing success was compared to a performance goal of 70.7%. The primary composite safety endpoint (major adverse event [MAE], clinically significant perforation or embolization, or grade C or greater dissection) was assessed over a 30-day follow-up period and compared to a performance goal of 13.0%.

RESULTS

A total of 85 patients were treated using the Wingman catheter for peripheral artery CTO crossing. Key patient characteristics were mean age of 71±9 years, 66% male, and mean lesion length of 188±94 mm in the superficial femoral artery (71%), popliteal artery (15%), or infrapopliteal arteries (14%). Both primary endpoints of the trial were met¾CTO crossing success was 90% (lower confidence limit=82.5%) and 5 primary safety events occurred in 4 (4.8%) patients (upper confidence limit=10.7%). Over 30 days of follow-up, Rutherford score decreased by at least 2 categories in 74% patients; the percentage of patients with normal hemodynamics assessed with the ankle-brachial index increased from 1% to 51%.

CONCLUSIONS

Among patients with a CTO that was unable to be crossed with a standard guidewire, the Wingman catheter was able to cross 90% of occlusions with a favorable safety profile.

Autofluorescence properties of balloon polymers used in medical applications

SIGNIFICANCE

For use in medical balloons and related clinical applications, polymers are usually designed for transparency under illumination with white-light sources. However, when illuminated with ultraviolet (UV) or blue light, most of these materials autofluoresce in the visible range, which can be a concern for modalities that rely on tissue autofluorescence for diagnostic or therapeutic purposes.

AIM

A search for published information on spectral properties of polymers that can be used for medical balloon manufacturing revealed a scarcity of published information on this subject. The aim of these studies was to address this gap.

APPROACH

The autofluorescence properties of polymers used in medical balloon manufacturing were examined for their suitability for hyperspectral imaging and related applications. Excitation-emission matrices of different balloon materials were acquired within the 320- to 620-nm spectral range. In parallel, autofluorescence profiles from the 420- to 620-nm range were extracted from hyperspectral datasets of the same samples illuminated with UV light. The list of tested polymers included polyurethanes, nylon, polyethylene terephthalate (PET), polyether block amide (PEBAX), vulcanized silicone, thermoplastic elastomers with and without talc, and cyclic olefin copolymers, known by their trade name TOPAS.

RESULTS

Each type of polymer exhibited a specific pattern of autofluorescence. Polyurethanes, PET, and thermoplastic elastomers containing talc had the highest autofluorescence values, while sheets made of nylon, PEBAX, and TOPAS exhibited negligible autofluorescence. Hyperspectral imaging was used to illustrate how the choice of specific balloon material can impact the ability of principal component analysis to reveal the ablated cardiac tissue.

CONCLUSIONS

The data revealed significant differences between autofluorescence profiles of the polymers and pointed to the most promising balloon materials for clinical implementation of approaches that depend on tissue autofluorescence.

Use of steerable catheters for endovascular procedures: Report of a CASE and literature review

We report a case of a celiac trunk stenting using a steerable guiding catheter, to fix a residual endoleak following fenestrated endovascular repair (FEVAR) of a thoraco-abdominal aortic aneurysm (TAAA). A systematic search of the literature about the use of steerable catheters was also performed on Pubmed according to the PRISMA Guidelines, including all papers in which the device was used for in vivo endovascular procedures. In our case report, the patient had undergone a failed attempt of cannulation due to the presence of a severely angulated and stenosed ostium of the vessel. A steerable catheter was then used to fix the residual endoleak. The search of the Literature retrieved 544 papers. Of them, 13 met the inclusion criteria and were therefore assessed. The use of steerable sheaths and catheters was reported as effective and safe for the cannulation of 157 target vessels in 131 endovascular procedures, with a success rate of 95.5% and no complications. The use of a steerable guiding catheter in our experience was safe and effective for the selective cannulation of a severely stenosed and angulated celiac trunk, to correct a residual endoleak after FEVAR for TAAA. Steerable catheters could be useful tools for the selective cannulation of target vessels with a challenging ostium.

Initial experience with the 3.3 Fr Mongoose® pigtail catheter for aortic angiography during patent ductus arteriosus closure in small patients

BACKGROUND

Smaller femoral arterial sheaths may be associated with fewer vascular complications. The 3.3 Fr Mongoose^® Pediavascular pigtail catheter is a catheter that allows higher flow rates, potentially resulting in improved angiographic quality. We reviewed our experience with this small catheter during patent ductus arteriosus (PDA) closure.

MATERIALS AND METHODS

Review of patients ≤20 kg in whom the Mongoose^® catheter was used during PDA closure from 12/13 to 4/15. Angiographic efficacy and procedural details were compared to ten 4 Fr catheter cases. Comparisons were performed using Mann-Whitney U-test; P < 0.05 was statistically significant.

RESULTS

Twelve (9 female) patients were catheterized with a 3.3 Fr Mongoose^®. Median weight 10.5 kg (range 6.4-18.2), height 81 cm (range 37-111), and body surface area (BSA) 0.47 m² (range 0.33-0.75) were similar to ten patients (3 females) in the 4 Fr control group (P = NS); median weight 9.9 kg (range 6-16.8), height 80 cm (range 64-102), and BSA 0.46 m2 (range 0.31-0.74). Angiographic quality was subjectively adequate with both with no difference in the median pixel density between the two techniques (3.3 Fr: 76.7 [range 33.5-90] and 4 Fr: [70; 38-102]; P = NS). Contrast used was similar between the groups (3.3 Fr: median 4.2 ml/kg and 4 Fr: 4.9 ml/kg; P = NS). Median radiation dose was similar in the two groups (3.3 Fr: 28.1 mGy [range 17.2-38] and 4 Fr: 38 mGy [range 20.4-58.5]; P = NS). All ducts were closed at latest follow-up (P = NS). No complications were encountered.

CONCLUSIONS

The 3.3 Fr Mongoose^® allowed similar angiography to the 4 Fr pigtail catheter, allowing safe and effective transcatheter PDA closure in small children.