Guidezilla guide extension catheter facilitated the delivery of long and bulky In.Pact Falcon drug-coated balloon for the treatment of chronic total occlusion lesion. Int J Cardiol. 2015;201:220-221. [PMID: 26298384 DOI: 10.1016/j.ijcard.2015.08.034]

Application of a rapid exchange extension catheter technique in type B2/C nonocclusive coronary intervention via a transradial approach

BACKGROUND

In transradial intervention procedures, poor back-up support and noncoaxial alignment of the guide catheter (GC) may result in failure of the balloon or stent to reach the targeted lesion. Methods to provide extra back-up support using the original GC and wire can improve procedural success with reduced complications. A rapid exchange guide extension catheter provides convenient and efficient back-up support while preserving the initial GC and inserted wire.

AIM

To evaluate the efficacy and safety of rapid exchange extension catheter in the treatment of type B2/C nonocclusive coronary lesions via the radial access.

METHODS

A total of 135 patients with type B2/C nonocclusive lesions who were treated via the transradial approach were enrolled in the study. The clinical characteristics, indications for use of the rapid exchange extension catheter, and procedural details and results were reviewed and analyzed. All procedure-related complications and major adverse cardiovascular events were recorded during the in-hospital stay and follow-up period.

RESULTS

The most common indication for the use of a rapid exchange extension catheter was vascular tortuosity (37.8%), followed by heavy calcification (28.9%), long lesions (20.0%), proximal stent (6.7%), in-stent restenosis (5.2%), and coronary origin anomalies (1.5%). The following technologies failed in passing targeted lesions before delivering the rapid exchange catheter: Multiple predilatation technique (57%), buddy wire technique (33.4%), balloon anchoring technique (5.9%), and cutting balloon modification (3.7%). The mean depth of the extension catheter intubation was 20.56 ± 13.05 mm, and the mean rapid exchange catheter service time was 18.9 ± 9.7 min. The mean length and diameter of stents were 33.5 ± 14.4 mm and 2.75 ± 0.45 mm, respectively. The total rate of technique success (balloon or stent successful crossing of the target lesion with this technique) was 94.8%.

CONCLUSION

The rapid exchange extension catheter technique showed acceptable safety and efficacy in the transradial coronary interventions of type B2/C nonocclusive coronary lesions. We recommend this technique to assist in complex lesion intervention via radial access.

Early clinical experience with Guidezilla for transradial interventions in China

Anatomic variations, calcified, tortuous, angulated lesions, and lack of support to increase the complexity of transradial intervention (TRI). Guidezilla is a mother-and-child catheter enabling increased support during complex interventions. As there are few published reports of its use, we describe our experience using this device to assist TRI in Chinese patients. The aim of this study was to investigate the efficacy and safety of the Guidezilla guide extension catheter in complex coronary interventions. Thirty-two patients’ clinical characteristics, angiographic details, and in-hospital outcome retrospectively collected between June 2015 and August 2017. Patients were 59.44 ± 10.48 years of age and 26 (81%) were men. The most frequent target vessels were the RCA (34%) and LAD (31%), patients had complex type C (53%) or B (47%) lesions, severely tortuous (41%) and angulated (22%).With the use of Guidezilla, technique success was 100%, and procedural success was 94%. The mean diameter of the deployed stents was 2.97 ± 0.37 mm, and the length was 27.19 ± 8.14 mm. The estimated mean distance of Guidezilla intubation into the target vessel was 7.66 ± 2.29 cm.The Guidezilla catheter extension safely facilitated successful completion of TRI in complex coronary artery lesions. This device can help interventionalists successfully perform difficult procedures.

The safety and feasibility of guidezilla catheter in complex coronary interventions and an observational study

The monorail Guidezilla guide extension catheter was designed to provide additional backup and facilitate device delivery in percutaneous coronary intervention (PCI) for complex coronary anatomy such as chronic total occlusion (CTO), extreme vessel tortuosity, diseased bypass grafts, and anomalous coronary arteries, among others.The present retrospective, single-center study included 188 consecutive patients who underwent PCI using the Guidezilla catheter from March 2015 to August 2016. Study outcomes were rates of target lesion crossing success, procedural success, and complications.The Guidezilla catheter was used most commonly in PCI of CTOs (45%) and heavy proximal calcification (37%), followed by tortuosity (10%), previously deployed proximal stents (4%), and coronary artery anomaly (4%). The right coronary artery (48%) was most commonly intervened followed by the left ascending (35%) and left circumflex (17%) arteries. Rates of target lesion crossing success and procedural success were both 99%, with one device-related periprocedural complication, namely proximal vessel dissection secondary to deep insertion which was successfully treated with stent implantation. Ninety percent of PCI were performed and completed successfully by radial access.In a single center with experienced operators, the use of the Guidezilla guide extension catheter in PCI of complex coronary anatomy performed mostly via radial artery access appeared safe and efficacious, and greatly facilitated device delivery.

P2X7 receptor as a novel drug delivery system to increase the entrance of hydrophilic drugs into cells during photodynamic therapy

The second-generation photosensitizer methylene blue (MB) exhibits photochemical and photophysical properties suitable for photodynamic therapy (PDT)-based cancer treatment. However, the clinical application of MB is limited because of its high hydrophilicity, which hinders its penetration into tumor tissues. Therefore, new methods to improve the entry of MB into the cytoplasm of target cells are necessary. Because MB has a mass of 319 Da, transient pores on the plasma membrane, such as the pore induced by the P2X7 receptor (P2X7R) that allows the passage of molecules up to 900 Da, could be used. Using MTT viability assays, flow cytometry experiments, and fluorescence microscopy, we evaluated the toxicity and phototoxicity of MB and potentiation effects of ATP and MB on cell death processes in the J774 cell line (via a P2X7-associated pore). We observed that treatment with 5 μM MB for 15 min promoted the rate of entry of MB into the cytoplasm to 4.7 %. However, treatment with 5 μM MB and 1 mM ATP for the same amount of time increased this rate to 90.2 %. However, this effect was inhibited by pretreatment with a P2X7 antagonist. We used peritoneal macrophages and a cell line that does not express P2X7R as controls. These cells were more resistant to PDT with MB under the same experimental conditions. Taken together, these results suggest the use of the pore associated with P2X7R as a drug delivery system to increase the passage of hydrophilic drugs into cells that express this receptor, thus facilitating PDT.

Novel "baby-in-mother" technique with the GuideLiner in the bifurcation coronary intervention with the protect-wire kept in the side branch

We report a case of percutaneous coronary intervention in a bifurcation lesion involving the left anterior descending artery and the first-diagonal branch. The lesion was calcified with vessel tortuosity. Despite adequate lesion preparation using scoring balloon, the stent was not deliverable, even with deep intubation of 7Fr-guiding catheter. The use of 6-in-7 guiding extension catheter would have required removal of wire from the diagonal branch. To avoid this situation, we down-sized the extension catheter to 5Fr, which was successful in delivering the stent without removal of the wire from diagonal branch. We have also demonstrated this novel technique on ex vivo bench testing.