Super-stiff guidewire or loach guidewire during percutaneous nephrolithotomy?

Objectives: The objectives of this work are to compare the outcomes between loach guidewire and super-stiff guidewire during percutaneous nephrolithotomy (PCNL) and find potential indications of different guidewires. Patients and methods: We retrospectively reviewed our institutional PCNL database from 2017 to 2021. Patients who underwent PCNL guided by loach guidewire were assigned to group A (489 patients); patients who received super-stiff guidewire were assigned to group B (269 patients). Preoperative demographic data, intraoperative parameters, and postoperative complications were compared. The conditions and reasons of failed placement of guidewire needed readjustment were evaluated as well. Results: Preoperative demographic data and most intraoperative parameters were not statistically different between the groups. Postoperative Clavien-Dindo complications were also comparable, with low rate of complications. However, failed placement of guidewire more occurred in group A (8.2% vs. 4.0%, respectively, p = 0.03). Compared with the super-stiff guidewire, the loach guidewire was easier pass/slip into any place either it be perinephric or blood vessels. In most failed group A cases and all failed group B cases, the guidewire was placed in the perirenal fat. Six patients (15%) in group A, the guidewires entered into vessels. Conclusions: Our results support that the faulty placement of loach guidewire is significantly more common compared with super-stiff guidewire. Double confirmation is needed to prevent a major complication out of wrong dilatation whenever there is doubt about the wrong location of the guidewire.

Stiff Guidewires in Endourology: What Is Stiffness?

Introduction: The aim of this study is to perform a literature review of stiff guidewires used in urology and to investigate if there is an official definition for stiffness (shaft rigidity) of wires. Materials and Methods: A literature search was performed for all English language articles in MEDLINE and Scopus databases, Google Scholar, and the official websites of international companies. Guidewires from different companies were included. Results: We analyzed 14 different stiff guidewires from the companies, Boston Scientific, Coloplast, Cook Medical, Olympus, Terumo, Rocamed, and Bard Urological, according to their characteristics. We found no concrete data regarding their stiffness on the official websites. In addition, there were a few published studies about the Amplatz Super Stiff guidewire (Boston Scientific), ZIPwire™ Stiff Nitinol Hydrophilic guidewire (Boston Scientific), HiWire Stiff Nitinol Core Wire Guide (Cook Medical), Amplatz Fixed Core Wire Guide (Cook Medical), and NiCore™ Nitinol Guidewire-Stiff (Bard Urological), whereas there were no available data for the majority of stiff guidewires. Conclusions: Stiff guidewires are listed in catalogs of companies without any information regarding their classification. They are only divided into stiff and standard versions without knowing the differences between them. The companies and their manufacturers should adopt a common method to calculate and define the stiffness of each guidewire.

Minimizing the risk for left ventricular rupture during transcatheter aortic valve implantation by reducing the presence of stiff guidewires in the ventricle.

OBJECTIVES: The presence of a stiff guidewire in the apex of the left ventricle (LV) is a known risk factor for LV perforation. Our goal was to minimize the risk of LV rupture during transcatheter aortic valve implantation (TAVI) by omitting the interaction between the stiff guidewire and the LV apex using a modified procedure. METHODS: A TAVI protocol designed to allow minimal interaction between a stiff guidewire and the LV was developed in Linköping University Hospital in Sweden. A total of 316 patients were treated exclusively by this approach between March 2014 and May 2018. RESULTS: All procedures were completed successfully. There were no cases (0%) of ventricular perforation. Only 1 patient (0.3%) had a pericardial effusion, and it was due to annulus rupture. There was 1 case of acute kidney injury (0.3%). Five patients (1.6%) required a new permanent pacemaker. Stroke occurred in 3 patients (0.9%). No patient had valve embolization. Vascular complications were experienced by 6 patients (1.9%). A mild paravalvular leak occurred in 27 (8.5%) patients. At 30 days post-TAVI, 6 patients (2%) had died. The mortality rate at 1 year was 8.6% (n = 20/232). CONCLUSIONS: Our series shows that TAVI without the prolonged use of a stiff guidewire in the LV apex is feasible. The risk of LV perforation is eliminated by this approach, and other procedural complications are limited.