Use of Sheath (Probing CatheterTM) to Enhance Efficacy of the ProbeTM Dilatation Catheter

Coronary angioplasty of very distal or subtotal lesions has been markedly improved with the recent development of the Probe^TM dilatation catheter. However, despite its very low profile, the Probe^TM has certain limitations. We describe a new device. the Probing Catheter^TM, that, in conjunction with the Probe^TM increases the success rate and facilitates coronary angioplasty of very distal or high grade lesions.     

Placement of Intracoronary Stents Mounted on Over the Wire Balloon Catheters Without Using Long Guidewires

The aim of this study is to investigate the feasibility, effectiveness, and safety of placement of intracoronary stents mounted on over the wire balloon catheters without using long guidewires. Fifteen consecutive patients underwent GR II stent placement. Over the wire balloon catheters and short guidewires were used. The new method was successful in 14 of 15 cases. No complications were observed. This novel technique using a short (instead of long) guidewire to place intracoronary stents mounted on over the wire balloon catheters was successful, and more convenient. (J Interven Cardiol 2000; 13:27–30)     

Intracoronary Irradiation with 186/188Rhenium Following Balloon Overstretch Injury Reduces Neointima But Does Not Impair Vasoreactivity of Porcine Coronary Arteries

Objective: The purpose of this study was to assess the effect of ^186/188rhenium (^186/188Re) on the neointimal proliferation and on the vasomotion of irradiated porcine coronary arteries following balloon injury. Background: Intracoronary radiation (IR) at doses of 10–25 Gy reduces intimal hyperplasia in animal models and lowers restenosis in clinical trials. The response of coronary arteries to acetylcholine (ACh) has been used to examine endothelial function, but this has not been reported in porcine coronary arteries subjected to overstretch balloon injury (BI) and subsequent IR. Methods: Vasomotor response was studied at baseline and at 2 weeks in 20 swine. Baseline vasomotor study without BI was carried out in six animals (12 arteries; Group I, no injury, no radiation). Subsequently the left anterior descending (LAD) and the left circumflex (LCX) arteries of 11 animals were subjected to BI. Eight of these animals (15 arteries) were subjected to IR with ^186/188Re in the LAD and LCX arteries in doses of 15 Gy followed by vasomotor studies at 2 weeks (Group II, BI, radiation). Three animals, (six arteries) of the BI group were not subjected to IR and their vasomotor functions assessed two weeks later (Group HI, BI, no radiation). Endothelium dependent vasomotion was assessed by Doppler flow wire and by quantitative coronary angiography (QCA) following selective infusion of serial doses of ACh proximal to the injured and irradiated segments. Nitroglycerin (200 μg) was injected intracoronary to detect endothelium independent vasodilatation. Histomorphometry and QCA analysis was performed to confirm the effect of IR on intimal area (IA), and IA corrected for fracture length (IA/FL). Results: Responses to ACh infusion and coronary flow reserve were similar at baseline before injury and at 2 weeks following injury with and without radiation. The irradiated vessels demonstrated normal vasodilatation responses to nitroglycerin. The irradiated vessels showed a marked reduction in IA and IA/FL. Conclusion: The vasoreactivity of irradiated coronary arteries is preserved at doses that inhibit neointima formation in the porcine model.     

Excimer Laser Angioplasty with Adjunctive Balloon Dilatation Versus Balloon Dilatation Alone for the Treatment of In-Stent Restenosis: Results of a Randomized Single-Center Study

Background: Laser ablation of neointimal tissue prior to balloon dilatation has been shown to be a potential treatment modality for restenosis within previously implanted stents. It remains controversial whether this treatment provides superior acute and long-term results compared to conventional balloon dilatation. Methods and Results: Between November 1995 and November 1996, 96 patients with significant (≥ 50%) in-stent restenosis were randomized to receive excimer laser angioplasty with adjunctive balloon dilatation (ELCA + PTC A, n = 47) or PTCA alone (n = 49). Both groups did not differ with regard to gender, clinical history, location of the lesion, reference diameter, or lesion length. Angiographic success was achieved in 46 patients with ELCA + PTCA (98%) and in 48 patients with PTCA alone (98%). In-hospital complications included acute closure in one patient of each group, one CABG, one repeat PTCA, and one non-Q wave MI with ELCA + PTCA, versus two bleeding and one death with PTCA. Clinical follow-up was obtained in all patients, while angiographic follow-up was available in 35 of 47 (ELCA+PTCA) versus 35 of 49 (PTCA) patients with a mean follow-up time of 163 ± 81 days. With ELCA+PTCA, MLD increased from 0.82 ± 0.38 to 1.99 ± 0.33 mm versus 0.81 ± 0.39 mm to 2.07 ± 0.60 mm with PTCA (P = NS). At follow-up, MLD was 1.32 ± 0.60 mm with ELCA + PTCA versus 1.45 ± 0.75 mm with PTCA (P = NS). Late adverse events included nine repeat PTCA with ELCA +PTCA (19%) versus 12 with PTCA (24%), three CABG with ELCA +PTCA (6%) versus two with PTCA (4%), and one death (2%) with PTCA (P = NS). Angiographic restenosis rate was 52% with ELCA + PTCA versus 47% with PTCA alone (P = NS). Conclusion: Our data suggest that excimer laser angioplasty with adjunctive balloon dilatation for the treatment of in-stent restenosis provides similar acute results as plain balloon dilatation and may offer no advantage over PTCA alone with regard to intermediate-term outcomes.     

Evidence for Expression of the Joa Blood Group Antigen on the Gya/Hy-Active Glycoprotein

The phenotypic association between the non-assigned high-incidence antigen Jo^a and the Gy^a collection antigens Gy^a and Hy was investigated by haemagglutination studies, flow cytometric analysis, immune precipitation and immunoblotting experiments. In haemagglutination tests anti-Jo^a gave the same pattern of reactivity with erythrocytes pre-treated with pronase, trypsin, α-chymotrypsin and thiol reducing agents as did anti-Gy^a and anti-Hy. In addition, similar to that found for anti-Gy^a and anti-Hy, anti Jo^a also showed reduced binding, as determined by haemagglutination and flow cytometric analysis, to erythrocytes from patients with paroxysmal nocturnal haemoglobinuria. Immune precipitates prepared from radio-iodinated antigen-positive red cells with anti-Jo^a, anti-Gy^a and anti-Hy gave similar results – a major component of M_r 49,000–60,000 (the Gy^a/Hy-active glycoprotein) and a second component of M_r 85,000–92,000 (this may be a dimer of the Gy_a/Hy-active glycoprotein, or a coprecipitated protein). These immune precipitates, when probed with both anti-Gy^a and anti-Hy under non-reducing conditions, gave a positive immunoblotting reaction to both the M_r 49,000–60,000 and the M_r 85,000–92,000 components. These results strongly suggest that the Jo^a antigen is expressed on the same glycoprotein that carries the Gy^a and Hy antigens.     

Successful Recanalization Using a Hydrophilic-Coated Guide Wire in Total Coronary Occlusions After Unsuccessful PTCA Attempts with Standard Steerable Guide Wires

During a balloon angioplasty procedure, cardiac interventionalists frequently have difficulty passing standard guide wires into coronary arteries with chronic total occlusion. In the past year, we encountered eight patients with occluded coronary arteries where standard guide wires were tried (average duration 15.5 minutes) but were unsuccessful. Application of a 0.025–0.035-inch hydrophilic guide wire was then attempted and was successful in recanalizing seven of the eight coronary occlusions (average duration 3.9 minutes). The channel created by the hydrophilic guide wire remained patent after its removal and permitted subsequent balloon angioplasty to be performed. Thus, in some patients with coronary occlusion where difficulty in guide wire passage is encountered, the application of a hydrophilic guide wire for crossing the occlusion and facilitating PTCA should be considered. However, a larger clinical series will be needed to determine the safety and efficacy of this technique.     

Experience with Preformed Catheters for Coronary Angiography by the Brachial Approach

Experience with a simplified technique for selective coronary angiography by the brachial cutdown approach using preformed coronary catheters in over 500 cases is described. This technique has facilitated selective catheterization of the coronary arteries in patients where use of the Sones catheter has proven difficult or impossible. Particularly, coronary arteries in patients with a dilated aortic root, high-rising left coronary artery or tortuous subclavian artery are easily catheterized with the preformed catheters described in this report. Shortened procedure time, an acceptable morbidity (1.4%) and mortality (0.2%), and improved coronary opacification by virtue of the ease in selectively entering the coronary ostia make these preformed catheters a useful modification to coronary angiography by the transbrachial approach.     

Adverse Events Associated with the Use of Guide Extension Catheters during Percutaneous Coronary Intervention: Reports from the Manufacturer and User Facility Device Experience (MAUDE) database

Background/purposeWe aimed to assess the reported complications and event modes for the GuideLiner and Guidezilla extension catheters.Methods/materialsThe US Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database was queried for reported events.ResultsOf the 65 cases with reported GuideLiner-related issues, 15 (23%) involved the inability to pass equipment through or damage to percutaneous coronary intervention (PCI) devices in the GuideLiner catheter, 38 (58%) involved GuideLiner catheter fracture, 9 (14%) involved coronary artery dissection, 2 (3%) involved coronary artery perforation, and 1 (1.5%) involved thrombus formation in the catheter. Of the 408 cases with reported Guidezilla-related issues, 53 (13%) involved inability to pass or damaged PCI devices into the Guidezilla catheter, 117 (29%) involved inability to advance the Guidezilla catheter to the target lesion, 59 (14%) involved kinked Guidezilla catheter, mostly because of partial or complete catheter fracture upon further investigation, 164 (40%) involved a broken Guidezilla catheter, 10 (2.5%) involved coronary artery dissection, 2 (0.5%) involved coronary artery perforation, 1 (0.2%)involved aortic dissection, 1 (0.2%) involved thrombosis formation, and 1 (0.2%) involved no-reflow phenomenon.ConclusionsFindings from the MAUDE database highlight the complications and modes of events associated with the use of GuideLiner and Guidezilla extension catheters.SummaryTo assess the reported complications and event modes for the GuideLiner and Guidezilla extension catheters, the US Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database was queried. There were more reports on Guidezilla-related events during the search period. The events for both extension catheters mainly involved the inability to pass equipment through or damage to percutaneous coronary intervention (PCI) devices in the extension catheter, extension catheter fracture, coronary artery dissection and perforation and, occasionally, the death of the patients.     

The Fyx phenotype is associated with a missense mutation in the Fyb allele predicting Arg89Cys in the Duffy glycoprotein

The molecular basis of the three major alleles ( Fy^a / Fy^b / Fy ) of the Duffy (FY) blood group system has recently been established but the Fy^x phenotype associated with weak expression of the Fy^b and other FY antigens is poorly understood.
In the Fy^x genes of five unrelated British and Swedish donors with the Fy(a+b+^weak) phenotype we found two missense mutations predicting amino acid changes Arg89Cys and Ala100Thr in the FY glycoprotein.
The same mutations were found in two Fy(a−b+^weak) samples from individuals of Swedish and Algerian origin. Their red blood cells showed a marked decrease in Fy^b, Fy3 and Fy6 expression measured by routine serology and flow cytometry. The rare FY genotypes Fy^xFy^x and Fy^xFy were confirmed by family studies and DNA sequencing.
Screening by allele-specific primer PCR (ASP-PCR) for these mutations among 100 Caucasian and 100 Black random blood donors indicated allele frequencies of 2.5% and 0%, respectively. Ala100Thr alone was present in 33% of the Caucasians (but none of the Blacks) with no weakening of FY expression.
A novel allele at the FY locus associated with the Fy^x phenotype was studied. Mistyping of this weak Fy^b antigen in clinical transfusion medicine may lead to delayed haemolytic transfusion reactions in immunized patients. A potential role for genomic typing is proposed.     

Production of a Murine Monoclonal Antibody to the Low-Incidence Red Cell Antigen Wra: Characterisation and Comparison with Human Anti-Wra

The production of a monoclonal antibody which detects the low-incidence red cell antigen Wr^a is described. The antibody (BGU1-WR) was isolated following immunization of BALB/tk mice with Wr(a+) cells. BGU1-WR is an IgGl antibody and reacted in a manner similar to human polyclonal anti-Wr^a with untreated, protease treated and chemically modified Wr(a+) cells.     

Human Monoclonal Anti-D with Reactivity against Category DVI Cells Used in Blood Grouping and Determination of the Incidence of the Category DVI Phenotype in the DU Population

B-lymphoblastoid cell lines transformed by Epstein-Barr virus were produced from cells obtained from a hyperimmunised donor with serum anti-D activity against category DVI red cells and enriched for this activity by rosetting with category DVI red cells. Three clones produced IgG1 anti-D and had stable cell growth and continuous secretion of antibody in prolonged culture. The monoclonal antibodies reacted with category DVI red cells, when assessed manually and in an automated blood grouping system, and are useful blood grouping reagents for the detection of the category DVI phenotype. Using a radiometric technique, the number of antibody molecules bound to category DVI red cells from 5 individuals was estimated to range from 2,800 to 11,200 per cell. Five percent of blood donors classed as Du in the south western region were found to have the category DVI phenotype.     

Studies on Anti-Mia and the MiIII Complex

Some Ms/Ms MiIII red cells react weakly with rabbit anti-N but not with human anti-N sera. Specificities of different anti-Mi-a within the Miltenberger complex have been defined by absorbtion studies with different Mi classes.