Intracoronary snaring of the retrograde guidewire: A novel method to solve compartment mismatch in complex retrograde CTO PCI.

The retrograde approach has allowed a remarkable improvement in the success rate of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). After collateral channel crossing, the most crucial aspect of retrograde CTO PCI is creating the connection between the antegrade and retrograde system. Currently, the most common technique to achieve this is reverse controlled antegrade and retrograde subintimal tracking. However, this maneuver sometimes fails due to compartment mismatch (intraplaque situation of one wire and extraplaque situation of the other). New approaches are therefore needed to overcome challenges in this important step of the procedure. Here we present an innovative solution to this problem, which involved capturing the retrograde guidewire (advanced into a side branch at the distal cap) with a microsnare that had been advanced antegradely: this severed the dissection flap separating the antegrade and retrograde system, thus allowing us to successfully recanalize the CTO.

An integrated population model reveals source-sink dynamics for competitively subordinate African wild dogs linked to anthropogenic prey depletion.

Many African large carnivore populations are declining due to decline of the herbivore populations on which they depend. The densities of apex carnivores like the lion and spotted hyena correlate strongly with prey density, but competitively subordinate carnivores like the African wild dog benefit from competitive release when the density of apex carnivores is low, so the expected effect of a simultaneous decrease in resources and dominant competitors is not obvious. Wild dogs in Zambia's South Luangwa Valley Ecosystem occupy four ecologically similar areas with well-described differences in the densities of prey and dominant competitors due to spatial variation in illegal offtake. We used long-term monitoring data to fit a Bayesian integrated population model (IPM) of the demography and dynamics of wild dogs in these four regions. The IPM used Leslie projection to link a Cormack-Jolly-Seber model of area-specific survival (allowing for individual heterogeneity in detection), a zero-inflated Poisson model of area-specific fecundity and a state-space model of population size that used estimates from a closed mark-capture model as the counts from which (latent) population size was estimated. The IPM showed that both survival and reproduction were lowest in the region with the lowest density of preferred prey (puku, Kobus vardonii and impala, Aepyceros melampus), despite little use of this area by lions. Survival and reproduction were highest in the region with the highest prey density and intermediate in the two regions with intermediate prey density. The population growth rate ( λ ) was positive for the population as a whole, strongly positive in the region with the highest prey density and strongly negative in the region with the lowest prey density. It has long been thought that the benefits of competitive release protect African wild dogs from the costs of low prey density. Our results show that the costs of prey depletion overwhelm the benefits of competitive release and cause local population decline where anthropogenic prey depletion is strong. Because competition is important in many guilds and humans are affecting resources of many types, it is likely that similarly fundamental shifts in population limitation are arising in many systems.

A Mislocation of Double-lumen Catheter Guidewire in Right Atrium Successfully Retrieved with Loop-wire Snaring: A Case Report.

The increasing rate of central vascular access use especially for hemodialysis access in Indonesia carries risk of retention of the guidewire to the heart resulting in a condition known as heart foreign bodies. We described a case of mislocation of double-lumen catheter guidewire to the right atrium in a patient planned to perform hemodialysis. The patient complained of dyspnea and swelling of extremities but the symptoms had already appeared before the insertion of the catheter due to the patient's underlying kidney disease arising conclusion that the foreign bodies itself are asymptomatic. The wire was found on chest x-ray and then confirmed on fluoroscopy during the retrieval procedure. Loop-wire was used to snare the guidewire. The wire was successfully evacuated and the patient was stable. The rare nature of the condition could become a challenge in recognizing the condition. Percutaneous retrieval is the preferred management of the condition.

"Retained wire femoral lead removal and fibroplasty" for obtaining venous access in patients with refractory venous obstruction.

BACKGROUND: Patients with wire and catheter refractory venous occlusion are traditionally referred for pectoral transvenous lead extraction (TLE) to obtain venous access. TLE causes 1-2 mm circumferential mechanical or laser destruction of tissue surrounding the lead(s). This not only exposes the patient to the risk of major complications but also can damage nontargeted leads. We present a series of patients where retained wire femoral lead removal and fibroplasty was used to obtain venous access in patients with refractory obstruction. METHODS: Between 2008 and 2021, we identified 17 patients where retained wire lead removal followed by fibroplasty was used to retain venous access. Demographic and procedural data were obtained by retrospective review of patient charts. RESULTS: We were able to successfully obtain venous access in all 17 patients in whom this technique was attempted. In two patients the target lead was less than or equal to 1 year old. In the remaining 15 patients, the average dwell time of the target lead(s) was 6 years. There were no procedure-related complications, and no changes in the parameters of other leads were noted. CONCLUSION: Retained wire femoral lead removal and fibroplasty is safe and highly efficacious at obtaining venous access in patients with refractory venous occlusion. If the target lead(s) is less than or equal to 1 year old, this technique can help obtain venous access at the time of the initial surgery, hence avoiding the need for TLE. Furthermore, in patients referred for TLE to obtain venous access, this technique by avoiding the use of TLE tools spares the patient of the associated risks.

Femoral extraction of transvenous leads and leadless pacemakers-A review of the data, tools, and procedural steps.

Extraction of transvenous leads via the femoral route might be needed when extraction via the implant vein fails or when retained lead fragments exist. The skill set required for this procedure is unique as it relies on the ability to snare and the use of a variety of shelf tools. In this era of leadless pacing, this skill set might be called upon more frequently. In this article, we review the data, tools, and procedural steps of femoral lead extraction and retrieval/extraction of leadless pacemakers.

Intracoronary snaring of the retrograde guidewire: How to overcome extreme takeoff angles in chronic total occlusion percutaneous coronary intervention.

Extreme angulation of coronary artery takeoff represents a challenge for wiring and device advancement in percutaneous coronary intervention (PCI). This anatomic feature is particularly adverse in cases of chronic total occlusion (CTO) of the ostial-proximal segment of the target vessel. In this setting, the retrograde approach can help getting access to the occlusion. However, difficulties might arise at the critical step of wire externalization, due to the need to overcome the extreme ostial angle. Here, we describe a case of successful CTO PCI of the proximal circumflex artery, which presented an extreme angle at its takeoff. Due to inability to perform antegrade wiring of the occlusion, the retrograde approach was undertaken via epicardial collaterals from the right coronary artery. Since conventional attempts at re-entering the antegrade guiding catheter failed due to the aforementioned extreme angle, the retrograde wire was snared in the mid left anterior descending artery, and externalization was performed. This case demonstrates the usefulness of coronary snares in the CTO operator's toolkit and shows how such devices can be used to safely and successfully complete challenging retrograde procedures.

Lost and found: Coronary stent retrieval and review of literature.

A 61-year-old man with a history of percutaneous coronary intervention (PCI) of the mid right coronary artery (RCA) with a drug eluting stent (DES), presented with non-ST segment elevation myocardial infarction. Coronary angiography demonstrated complex disease of the distal RCA as well as in-stent stenosis of the previously placed mid RCA stent. The patient underwent bifurcation PCI of the distal RCA followed by attempted intervention with a DES on the mid RCA lesion. The stent could not cross the lesion and eventually became dissociated from its delivery system. The lost stent was successfully retrieved using two different snaring systems. The procedure was terminated without further attempts for stent delivery. The patient had an uneventful recovery and underwent successful PCI of the mid RCA lesion one month later.

A spatial approach to combatting wildlife crime.

Poaching can have devastating impacts on animal and plant numbers, and in many countries has reached crisis levels, with illegal hunters employing increasingly sophisticated techniques. We used data from an 8-year study in Savé Valley Conservancy, Zimbabwe, to show how geographic profiling-a mathematical technique originally developed in criminology and recently applied to animal foraging and epidemiology-can be adapted for use in investigations of wildlife crime. The data set contained information on over 10,000 incidents of illegal hunting and the deaths of 6,454 wild animals. We used a subset of data for which the illegal hunters' identities were known. Our model identified the illegal hunters' home villages based on the spatial locations of the hunting incidences (e.g., snares). Identification of the villages was improved by manipulating the probability surface inside the conservancy to reflect the fact that although the illegal hunters mostly live outside the conservancy, the majority of hunting occurs inside the conservancy (in criminology terms, commuter crime). These results combined with rigorous simulations showed for the first time how geographic profiling can be combined with GIS data and applied to situations with more complex spatial patterns, for example, where landscape heterogeneity means some parts of the study area are less likely to be used (e.g., aquatic areas for terrestrial animals) or where landscape permeability differs (e.g., forest bats tend not to fly over open areas). More broadly, these results show how geographic profiling can be used to target antipoaching interventions more effectively and more efficiently and to develop management strategies and conservation plans in a range of conservation scenarios.

Unexpected coil mass migration during transvenous embolization of a dural arteriovenous fistula resolved with guidewire-assisted snaring technique.

Endovascular embolization is a standard treatment for dural arteriovenous fistulas (dAVFs). Although it is considered relatively safe, intraoperative and postoperative complications can occur. Herein, a rare case of unexpected coil mass migration requiring a retrieval procedure during sinus occlusion for a transverse-sigmoid sinus dAVF (TSdAVF) is described. An 83-year-old man presented with worsening decline in cognitive function. Magnetic resonance angiography showed a TSdAVF. Since his symptoms seemed to be a result of the TSdAVF, transvenous embolization preserving the normal cranial venous circulation was planned. During sinus occlusion, including embolization of the shunted pouch of the TSdAVF, unexpected migration of the coil mass to the confluence of the superior sagittal sinus and the transverse sinus occurred. The migrated coil mass impeded venous circulation in the superior sagittal sinus. Since the presence of the coil mass at the confluence could have had catastrophic sequelae, the coil mass was retrieved using a guidewire-assisted snaring technique. Sinus occlusion was subsequently completed with repositioning of the coil mass at the target site. The TSdAVF resolved, with no recurrence confirmed for 1 year. Clinicians should be aware that coil mass migration can unexpectedly occur during sinus occlusion performed for treatment of a TSdAVF. The guidewire-assisted snaring technique might be effective in resolving this intraoperative complication.

Chemotherapy Port Peal Away Sheath Embolisation and Removal With Endovascular Snaring.

Chemotherapy port implantation is a common procedure for long-term intravenous access in cancer patients. While generally safe, complications can occasionally occur. This case report describes a rare complication of chemotherapy port placement, specifically peel away sheath embolisation, and its successful endovascular removal using snaring techniques. The purpose of this report is to highlight this uncommon complication and discuss the management strategy employed in our case.

Dealing With a Nightmare: A Case Report of Successful Percutaneous Treatment of an Embolized Occluder Device Complicating a Minimal-Fluoroscopy Patent Ductus Arteriosus Closure.

Patent ductus arteriosus (PDA) is one of the most prevalent acyanotic congenital heart diseases. Percutaneous closure of PDA has been the preferred treatment recommended by the guidelines due to relatively low complications and rapid patient recovery. However, device emboli remain the most frequent and disastrous complication, necessitating percutaneous or surgical treatment. We present a case of a large PDA closure in pulmonary arterial hypertension paediatric patients complicated with device emboli that was successfully retrieved using the snaring technique. Transcatheter retrieval, although technically challenging, is a feasible treatment and offers the advantage of avoiding the need for surgical intervention.

Snare technique to facilitate 'tall-in-short' redo-TAVR.

An 82-year-old man with a prior history of transcatheter aortic valve replacement (TAVR) with a 23-mm balloon-expandable transcatheter heart valve (THV) presented with bioprosthetic stenosis.

Transseptal snaring technique as a bailout from valvuloplasty balloon entrapment within a self-expanding valve: a case report.

Background: Transcatheter aortic valve replacement (TAVR) has become the dominant treatment strategy for severe aortic stenosis in patients with high and intermediate surgical risk. Although complications are significant cause of increasing mortality after TAVR and bailout techniques have been well established, we still encounter a rare complication without widely accepted bailout option. We present a rare complication of valvuloplasty balloon entrapment to a self-expanding valve strut with successful bailout. Case summary: A 71-year-old man complaining of dyspnoea underwent valve-in-valve TAVR for failed surgical aortic valve. However, he developed acute decompensated heart failure due to high residual aortic gradient (peak aortic velocity of 4.0 m/s and mean aortic gradient of 37 mmHg) on the 3rd day after TAVR. Computed tomography demonstrated underexpansion of transcatheter heart valve (THV) within the surgical valve. Therefore, urgent balloon valvuloplasty was performed. The balloon entrapment in the THV stent frame happened during the procedure. Percutaneous removal through transseptal approach using snaring technique was successfully performed. Discussion: Balloon entrapment within a THV is a rare complication and potentially requires urgent surgical removal. To our knowledge, this is the first report utilizing the snaring technique through transseptal approach for balloon entrapment within a THV. Through the current report, we highlight the utility and effectiveness of the transseptal snaring technique with using a steerable transseptal sheath. Moreover, this case shows the importance of the multiprofessional approach to resolve unexpected complications.

Successful management of tracheal lobular capillary hemangioma with arterial embolization followed by electrosurgical snaring via flexible bronchoscopy in an 11-year-old boy: A case report and literature review.

Lobular capillary hemangioma (LCH), previously known as pyogenic granuloma, is a benign vascular lesion commonly found within the oral and nasal cavities. However, it is rarely encountered within the trachea, especially in pediatric patients, where it manifests as hemoptysis, cough, and wheeze, and is frequently misdiagnosed as bronchitis or asthma. There is limited literature on the presentation, behavior, and management of tracheal LCH. Herein, we describe a rare case of tracheal LCH in an 11-year-old boy with a history of hemoptysis, which was successfully managed with arterial embolization followed by electrocautery loop snaring via flexible bronchoscopy. No complications occurred during and after the procedure. A review of the relevant literature is also provided. Our case is unique, given the therapeutic strategy utilized for pediatric tracheal LCH, and reminds physicians to be aware of tracheal LCH in the differential diagnosis for hemoptysis.

"Catch, Flip, and Remove" Technique for Retrieval of a Hypermobile Detached Leadless Pacemaker: A Case Report and Literature Review.

Leadless pacemaker (LP) detachment is a rare but life-threatening complication that may occur during implantation. While different snaring techniques have been described to remove partially or completely detached LPs, there are currently no reports of snaring a hypermobile LP that travels between different cardiac chambers. This report describes a technique to successfully snare a hypermobile detached LP by first "catching" onto the tines for stabilization with the help of a multi-loop snare, followed by using a second snare for the proximal retrieval feature.

Alpha-Loop Snaring Technique: Facilitated Snaring Technique for Fully-Deployed and Deformed Coronary Stent Protruding Into the Aorta.

A 59-year-old female was admitted for non-ST-segment elevation myocardial infarction and Killip class 3 heart failure with a left ventricular ejection fraction of 30%. Coronary angiogram showed moderate to severe stenosis over the ostial-proximal left anterior descending artery with minor disease over the left circumflex artery and right coronary artery. We describe a complication encountered where a protruding stent was weakened and elongated during our attempts to remove it, risking possible breakage, stent embolization, and long stent protrusion inside the aorta. We then describe treatment with what we call the alpha-loop snaring technique, which, to our knowledge, is the first report describing this novel approach, which can salvage a failing snaring attempt of a completely deployed and dislodged coronary stent.

A Stepwise Approach Utilizing a Double-Helix Wire Technique, Snare Capture and a Switch From a Transfemoral to Transradial Approach to Remove an Entrapped Balloon.

During an attempted PCI utilizing a femoral approach, a balloon became entrapped in the Left Circumflex Artery. Initial retrieval efforts including pulling the balloon and inflating a second balloon over the entrapment failed, the balloon fractured, and the distal end of the balloon apparatus migrated out of the guide catheter. We utilized a stepwise approach with a double helix wiring technique, snares and a change from a transfemoral to transradial approach to successfully retrieve the foreign bodies. This case highlights the importance of utilizing multiple techniques in series and understanding anatomical influences on equipment retrieval when single techniques and approaches fail.

Distal retrieval of dislodged and migrated guidewires after retrograde puncture of the deep femoral and dorsal pedal artery. A case series.

We report on retrograde retrieval of the soft end of dislodged guidewires during complex interventions. Interventionalists may consider this as an option for the endovascular management of this complication if an antegrade retrieval is not possible or fails.

Percutaneous Retrieval of a Left Atrial Appendage Closure Device: The Device Waltz.

Embolization of a device in patients undergoing percutaneous left atrial appendage closure is an uncommon complication. We present an illustrative case of successful percutaneous retrieval of an embolized LAmbre device (Lifetech Scientific, Shenzhen, China) that was achieved with a combination of a snaring technique and forceps grasping and by using a steerable guiding catheter. (Level of Difficulty: Advanced.).

Intracardial Catheter Migration of a Ventriculoperitoneal Shunt: Pathophysiology and Interdisciplinary Management.

BACKGROUND: Intracardial migration of a ventriculoperitoneal (VP) shunt (ICMVP) is a rare complication that has been described in only single case reports. Here we report the successful interdisciplinary management of an ICMVP and provide a review of the relevant literature. CASE DESCRIPTION: A 38-year-old-patient with shunt-dependent hydrocephalus caused due to a Blake's pouch cyst presented in our hydrocephalus outpatient clinic with thoracic pain and nocturnal cough at 7 months after VP shunt implantation (with initially a proper location on computed tomography scan of the head and X-ray of the abdomen). A new X-ray of the abdomen and the thorax revealed a dislocated shunt with migration of the distal catheter into the superior cava vein, right atrium, and right heart ventricle, with some loops in both pulmonary arteries. The catheter was successfully removed by an interdisciplinary team in general anesthesia under ultrasound, X-ray guidance, and cardiovascular parameter control by withdrawing the shunt into the superior cava vein and removing the remnant portion of the distal catheter (with a knot) by interventional snaring. Cardiac and vascular surgeons were on standby. CONCLUSIONS: The management of an ICMVP is complex and carries a high risk for severe potential complications. Two different pathophysiological mechanisms have been discussed in the literature, including gradual erosion into an adjacent vein and transvenous catheter placement of the initial shunt secondary to subcostal placement of shunt tunneling instruments. The suction effect of the venous system results in gradual pulling of the catheter into the venous system.