Percutaneous Transluminal Coronary Angioplasty Catheters Research Articles

Detrimental Effects of Sterilization Types on Single-Use Coronary Angioplasty Catheters for Reuse: An Electron Microscopic Study.

Reuse of medical devices poses risks concerning technical issues and patient safety. In this study, we aimed to examine the structural changes in catheters that occur due to the reuse with the aid of electron microscopy. The effects of hydrogen peroxide (HP) and ethylene oxide (EO) sterilization on four percutaneous transluminal coronary angioplasty (PTCA) catheters and control PTCA catheters were examined by scanning electron microscope (SEM). Each catheter sample was divided into four parts during the SEM examination, and a total of 20 pieces were examined. Catheters were reprocessed through every regular sterilization step and used solely for the study, not in patients. Statistical evaluations of histological scoring made on images obtained from scanning electron microscopic images were made using the GraphPad Prism 8 program. Electron microscopical examination showed that HP sterilization caused more robust and deeper lines compared to EO. These distortions increased directly with the increase in the reprocessing cycle. In EO, no significant damage was detected within five cycles in contrast to HP; however, the harmful effects of EO were seen over five cycles. Unprocessed samples had no damage. Outer and inner deterioration was significantly higher in the EO>5 group and HP>5 group than in the control group. However, the bacterial contamination score in the EO>5 group was higher than the control group. Our findings showed that HP and EO sterilizations caused some deterioration in the inner and outer surfaces of PTCA catheter samples. We recommend reprocessing using EO, the least damaging method, when necessary, and paying attention not to exceed five cycles when necessary.

Post-marketing surveillance in the published medical and grey literature for percutaneous transluminal coronary angioplasty catheters: a systematic review

BackgroundPost-marketing surveillance (PMS) may identify rare serious incidents or adverse events due to the long-term use of a medical device, which was not captured in the pre-market process. Percutaneous transluminal coronary angioplasty (PTCA) is a non-surgical procedure that uses a balloon-tipped catheter to enlarge a narrowed artery. In 2011, 1,942 adverse event reports related to the use of PTCA catheters were submitted to the FDA by the manufacturers, an increase from the 883 reported in 2008. The primary research objective is to conduct a systematic review of the published and grey literature published between 2007 and 2012 for the frequency of incidents, adverse events and malfunctions associated with the use of PTCA catheters in patients with coronary artery disease (CAD). Grey literature has not been commercially published.MethodsWe searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials and PubMed for medical literature on PMS for PTCA catheters in patients with CAD published between January 2007 and July 2012. We also searched the grey literature.ResultsThis review included 11 studies. The in-hospital adverse events reported were individual cases of myocardial infarction and hematoma. In studies of patients with coronary perforation, more patients with balloon angioplasty were identified compared with patients who required stenting.ConclusionsOur systematic review illustrates that the volume and quality of PMS studies associated with the use of PTCA catheters in patients with CAD are low in the published and grey literature, and may not be useful sources of information for decisions on safety. In most studies, the objectives were not to monitor the long-term safety of the use of PTCA catheters in clinical practice. Future studies can explore the strengths and limitations of PMS databases administered by regulatory authorities.

How firms set prices for medical materials: A multi-country study

This study presents a comparison of medical material prices, discusses why differences exist, and examines methods for comparing prices. Market prices for drug-eluting stents (DES), non-drug-eluting stents (non-DES), and percutaneous transluminal coronary angioplasty (PTCA) catheters were collected from five countries: the United States, Japan, Korea, Turkey, and Thailand. To compare prices, three adjustment methods were used: currency exchange rates, purchasing power parity (PPP), and gross domestic product (GDP) per capita. The ratios of medical material prices compared with those in the United States were higher in Japan (from 1.4 for DES to 5.0 for PTCA catheters) and Korea (from 1.2 for DES to 4.0 for PTCA catheters), and lower in Turkey (from 0.8 for non-DES to 1.4 for DES) and Thailand (from 0.5 for non-DES to 1.3 for PTCA catheters). The PPP-adjusted ratios changed slightly for Japan, Korea, and Turkey. When the prices were adjusted by GDP per capita, the ratios were much higher. Comparing prices using currency exchange rates or PPP is applicable only between countries with stable economic relations; adjustment by GDP per capita reflects the actual burden. Further study is needed to fully elucidate the factors influencing the global medical material market.

Reprocessing single-use cardiac catheters for interventional cardiology. A cost-minimization model for estimating potential saving at departmental scale and national level

Background: The utilization of single-use percutaneous catheters (SUDs) is a common practice in interventional cardiology, but the increasing of cardiac interventions and the consequent economic load demand for assessing SUDs’ reuse. The study aimed at estimating the potential saving for Italian cardiology departments in the hypothesis that reprocessing and reuse of SUD is performed by guaranteeing safety and efficiency of the reconditioned device as high as the new marketed one. Methods: A cost-minimization model was applied from the perspective of the health national service. Input parameters for the model were settled by reviewing published data on technical, hygiene and functional properties of reprocessed electrophysiology (EP) and percutaneous transluminal coronary angioplasty (PTCA) catheters. Potential saving at department level was calculated as percentage of the actual expenditure for purchasing single-use devices. Two-ways sensitivity analysis was conducted on main cost drivers. Finally, saving at national level was estimated. Results: The revision of technical and safety data showed the feasibility of reprocessing and reuse of EP and PTCA catheters under determined constrains. Potential savings of 39%, and 12% were calculated at department level for EP and PTCA catheters, respectively. Sensitivity analysis showed saving was dependent primarily on departmental workload. Major variations in saving occurred in the range between one and 200 catheters per year. The cut-off between benefit and charges was also related to regeneration rate and maximum number of uses. The estimate of potential saving at national level ranged in the interval from €19.85M to €24.24M. Conclusions:When safety and efficiency is assured by certified reuse processing, substantial saving could be achieved both at departmental and national level contributing to optimize budget allocation for the healthcare system.

Retrieval Of A Fractured And Retained Percutaneous Coronary Angioplasty Catheter On Beating Perfused Heart

A fractured and retained percutaneous transluminal coronary angioplasty catheter was successfully removed on a perfused beating heart with concomitant bypass grafting. We believe this is the first report in English literature of such an operation on a beating heart.Broken and retained percutaneous transluminal coronary angioplasty balloon catheter is a rare but serious complication of interventional cardiology. The presence of a calcified proximal lesion hinders withdrawal of the broken catheter. It requires retrieval and emergency coronary bypass grafting to prevent further complications.

Price Disparity of Percutaneous Coronary Intervention Devices in Japan and the United States in 2006

The price disparity between Japan and foreign countries for medical devices is a controversial issue. Price differences existed between Japan and USA for various medical devices in early 2005, so in the present study, a more precise and detailed investigation of the latest market prices of medical devices between Japan and USA was conducted in 2006, focusing on coronary stents and percutaneous transluminal coronary angioplasty (PTCA) catheters, for an evaluation of the efficacy of current Japanese policies. Japanese market prices were obtained from 31 university hospitals, and US market prices were obtained from 1 hospital chain and 2 group-purchasing organizations. The price ratio (Japanese market price/US market price) was determined to be 1.2-1.4 for drug-eluting stents (DES), 1.6-2.4 for non-DES, and 4.1-5.1 for PTCA catheters. Results showed that the price disparity was relatively small for DES, but still significant for non-DES and PTCA catheters. Radical measures must be taken to improve the fundamental causes of price disparity and might include reviewing the implementation of the Japanese Pharmaceutical Affairs Law, abolishing the reimbursement price system for medical devices, and establishing centers of clinical excellence.

Multifunktionale Prüfung von PTCA-Ballonkathetern

New in vitro measuring methods for balloon catheters used for percutaneous transluminal coronary angioplasty (PTCA) and their verification in a complex test device are presented. This system can mimic all relevant application situations. The central element of the test device is a coronary vessel model matching the physiological situation in terms of geometrical structure and frictional properties. Reactive force sensors are used to measure the application-relevant forces exerted by the catheter on the model vessel walls and accessories, such as guide wire and guiding catheter. To generate a kink-free advancement of the catheter and permit measurement of the active forces, an alternating drive unit has been specially developed. The testing and application of the newly developed methods revealed statistically significant differences between various types of catheter. The test device closes a gap between complex but subjective clinical tests, and individual objective, but application-removed in vitro test setups for PTCA catheters. While the initial prototype had shortcomings with regard to the reproducibility of measurements, successor systems developed for industrial use are now in production. The properties of these measuring systems developed for the benefit of manufacturer and reprocessor of PTCA catheters are discussed.

Reuse of angioplasty catheters and risk of Creutzfeldt-Jakob disease

Background In 1996, the Quebec Ministry of Health and Social Services, concerned that reuse of devices contaminated with blood or blood products could cause the transmission of Creutzfeldt-Jakob disease (CJD), discontinued its practice of reusing angioplasty catheters despite the significant cost savings reuse had afforded the health care system for several years. The objective of this study was to establish whether the medical literature provides documentation of any cases in which CJD was transmitted by reused percutaneous transluminal coronary angioplasty (PTCA) equipment. Methods and Results A Medline search was performed to identify previous studies that examined this issue. Key words for the search included PTCA, CJD, and material and equipment reuse. A substantial amount of effort has been spent on the study of PTCA catheter reuse in relation to the risk of infection, toxicity, and catheter breakage as well as cost. In Québec, studies by the Conseil d’Évaluation des Technologies de la Santé investigated the effectiveness of cleaning and sterilizing PTCA equipment and considered the possibility that reuse of single-use catheters, hemodialyzers, and cardiac pacemakers could spread CJD. A number of other studies found evidence that iatrogenic transmission was responsible for several cases of CJD by direct implantation in or adjacent to the central nervous system during neurosurgery. CJD was also transmitted to human beings by injection of pituitary growth hormone and to mice through cerebral inoculation of contaminated blood and urine. However, there were no documented cases of CJD occurring as a complication of PTCA equipment reuse. Conclusions The current literature indicates that there are no known cases of CJD attributable to the reuse of PTCA devices contaminated by blood or to the transfusion of blood or blood products. This practice is associated with a very low risk of CJD transmission. With the considerable cost savings made possible by reuse of PTCA equipment, reimplementation of this practice should be considered by health delivery systems, provided that stringent methods of cleaning and sterilization are observed. (Am Heart J 1999;137:1173-8.)

Transcranial Doppler detection of microemboli during percutaneous transluminal coronary angioplasty.

The use of percutaneous transluminal coronary angioplasty (PTCA) to treat coronary artery disease is now commonplace. The occurrence of microemboli during invasive procedures such as cardiac angiography and bypass surgery is well documented, although neurological complications are relatively uncommon. To date, no investigation has been undertaken of the frequency or nature of microemboli occurring during PTCA or of the correlation with aortic atheroma. Twenty patients having elective PTCA underwent examination by transcranial Doppler ultrasonography (TCD) to detect left middle cerebral artery microemboli occurring during the procedure. Blinded off-line analysis correlated microembolic signal counts on TCD with the components of each stage of the PTCA. Patients later underwent transesophageal (TEE) echocardiography, with measurements made of the thickness of the intima and atheroma in the ascending and descending thoracic aortic arch by cardiologists blinded to the TCD results. A total of 973 microembolic signals were detected (mean+/-SD, 48.7+/-36.7 per patient); 196 (20%) occurred on movement of the PTCA catheter and wire around the aortic arch, 84 (9%) with other PTCA catheter-associated movements, and 679 (70%) in association with injection of solutions (eg, saline and contrast). Mean signal counts during contrast injection were significantly greater than during the other 3 phases (P<0.001). No neurological events occurred in the study. Although not statistically significant, there was a trend toward greater microembolic signal counts with the number of times the catheter was passed around the aortic arch and the amount of arch atheroma detected by transesophageal echocardiography. Microemboli detected on TCD are a common occurrence during PTCA but are largely asymptomatic. The majority of microembolic signals are most probably gaseous in origin and do not appear to be related to the extent of aortic atheroma or to clinical events.

Initial Experience With Reuse of Coronary Angioplasty Catheters in the United States

Objectives. We sought to evaluate the performance of angioplasty catheters, restored under a strict manufacturing process, in patients with coronary artery disease.Background. Most countries outside the United States routinely reuse disposable medical equipment, resulting in significant cost savings. Because of quality and legal concerns, reuse in the United States has been limited. We investigated the reuse of percutaneous transluminal coronary angioplasty (PTCA) balloon catheters, restored by a process strictly controlled for bioburden and sterility, in patients undergoing PTCA.Methods. Used PTCA balloon catheters were shipped to a central facility and were decontaminated, cleaned and tested for endotoxin using the limulus amebocyte lystate (LAL) gel clot method. Physical testing and quality assurance were performed. The products were packaged and sterilized with ethylene oxide. Catheter performance was assessed in a pilot study powered to detect a 5% difference in the angiographic failure rates of new and reused balloons (beta 0.8).Results. The study enrolled 107 patients. The indication for PTCA was stable angina pectoris in 69 patients, unstable angina in 22 and acute myocardial infarction in 16. Of the 107 patients enrolled, 106 had a successful laboratory outcome, and 1 required coronary artery bypass graft surgery after failed rescue stenting. There were 122 lesions attempted (American College of Cardiology/American Heart Association classification A, n = 32; B1, n = 43; ≥B2, n = 35; C, n = 12). Of the 110 lesions initially approached with restored PTCA catheters, 108 were crossed and dilated. Sixty-four required no further procedures. Stenting was performed in 37 patients (29 planned, 8 rescue). Thus, the angiographic failure rate was 7% (10 of 108, 95% confidence interval 2% to 12%), comparable to the 10% rate seen with new balloons in other studies.Conclusions. Restoration of disposable coronary angioplasty catheters using a highly controlled process appears to be safe and effective, with success rates similar to those of new products and no detectable sacrifice in performance. Cost analysis suggests that implementation of reuse technology for expensive disposable equipment may offer cost savings for U.S. hospitals, without sacrifice of quality.

Multicenter Evaluation of Fixed‐Wire PTCA Catheters with Modified Distal Tips: Initial and 2‐Month Follow‐Up Results

Lesions in the distal portion of coronary arteries are technological challenges with currently available percutaneous transluminal coronary angioplasty (PTCA) equipment. A study was performed at multiple centers to determine if new “fixed‐wire” devices with a modified distal tip (a 2‐cm flexible tip and 1‐cm standard tip) would be useful in these situations. Three hundred twenty‐three patients were included in the study, 75% male, mean age 63 ± 11 years. Four hundred ninety‐three lesions were attempted; the overall success rate was 85%. Forty‐six (14.2%) clinical complications occurred including: 5 deaths (1.1%); 2 nonfatal myocardial infarctions (0.6%); and 6 emergency coronary artery bypass grafting procedures (2.6%). A device malfunction was noted in 32 patients (9.9%), and included: 8 balloon ruptures or perforations (2.0%); 6 bent or damaged tips (1.9%); and 4 shaft/manifold leaks (1.2%). Two‐month follow‐up assessment for restenosis was done in 352 of 371 (95%) patients and at that time 89% were asymptomatic, had a negative functional test, or patent PTCA site by angiography. The new fixed‐wire PTCA catheters with 1‐ and 2‐cm flexible tips hold promise for dilating lesions in distal locations with an acceptable rate of complications. Additional investigation is needed to determine their role in the treatment of coronary artery disease with PTCA.

Evaluation of the Cathetron system for recycling angioplasty catheters

The Cathetron (Minntech Corporation, Minneapolis, MN) peracetic acid-based reprocessing method for percutaneous transluminal coronary angioplasty (PTCA) catheters was evaluated for ability to sterilize and maintain catheter integrity. The balloons and lumens of 42 catheters (140 reprocessing cycles) were inoculated with suspensions of Staphylococcus epidermidis, S. aureus, Pseudomonas aeruginosa, and Bacillus circulans. Five catheters failed the initial evaluation of mechanical integrity and were discarded. Cultures from 37 catheter lumens, balloons, and hubs (n = 349) were negative following reprocessing. The Cathetron system reliably sterilized PTCA catheter; however, further studies using different brands of catheters and evaluating catheter sterility over time under storage conditions are required. Cathet. Cardiovasc. Diagn. 41:132–135, 1997. © 1997 Wiley-Liss, Inc.

Evaluation of the cathetron system for recycling angioplasty catheters.

The Cathetron (Minntech Corporation, Minneapolis, MN) peracetic acid-based reprocessing method for percutaneous transluminal coronary angioplasty (PTCA) catheters was evaluated for ability to sterilize and maintain catheter integrity. The balloons and lumens of 42 catheters (140 reprocessing cycles) were inoculated with suspensions of Staphylococcus epidermidis, S. aureus, Pseudomonas aeruginosa, and Bacillus circulans. Five catheters failed the initial evaluation of mechanical integrity and were discarded. Cultures from 37 catheter lumens, balloons, and hubs (n = 349) were negative following reprocessing. The Cathetron system reliably sterilized PTCA catheter, however, further studies using different brands of catheters and evaluating catheter sterility over time under storage conditions are required.

Cost-efficacy modeling of catheter reuse for percutaneous transluminal coronary angioplasty

Objectives. Our goal was to provide the range of cost savings associated with various catheter reuse strategies.Background. Percutaneous transluminal coronary angioplasty catheters are commonly reused in several countries outside the United States. However, the cost-effectiveness of such reuse strategies has not been evaluated.Methods. Three theoretical models of catheter reuse were constructed using the actual costs for treating patients with coronary angioplasty at the Cleveland Clinic. Costs were calculated based on the number of balloon catheters, the amount of contrast agent used and the rates for urgent revascularization that were observed in a prospective Canadian study on catheter reuse.Results. The median cost to treat a lesion by means of coronary angioplasty using new catheters was $8,800 per patient. In reuse models, the potential to reduce cost depended on the number of balloon catheters used and the rates of urgent revascularization. The “best case” scenario offered a potential savings of $480 (5.5% of total in-hospital cost), whereas the “worst case” scenario resulted in an increased cost of $1,075 (12.2% of total in-hospital cost) compared with the single-use strategy. Cost of the “likely case” scenario was similar to that of the single-use strategy. Sensitivity analyses identified the different rates of revascularization and cost of balloon catheters required to offset potential savings in each strategy.Conclusions. Although reusing coronary angioplasty catheters may reduce total in-hospital costs, even a modest increase in complications requiring urgent revascularization may offset any potential savings. However, if an increase in complications and procedure time can be avoided, the reuse strategy has significant economic potential and, ultimately, may be extended to other percutaneous coronary interventional equipment.

Distal coronary hemoperfusion during percutaneous transluminal coronary angioplasty.

Distal coronary hemoperfusion during percutaneous transluminal coronary angioplasty (PTCA)-with an autoperfusion balloon or active system-facilitates prolonged balloon inflation. Prolonged inflations may tack up intimal dissections and improve the primary angioplasty result in complex lesions. Additionally, distal perfusion may reduce the likelihood of cardiogenic shock during high-risk PTCA. Autoperfusion balloons are most frequently used to treat acute or threatened closure. There currently is no prospective clinical study showing that stent implantation for this complication is more successful and more cost-effective. The blood flow rates through autoperfusion balloons may not abolish myocardial ischemia, and higher flow rates can often be achieved with pumps. Therefore, during high-risk PTCA, pumps may be preferred to prevent hemodynamic collapse. Clinical application of perfusion pumps is hampered by the risk for mechanical hemolysis during prolonged perfusion and the high velocity of the bloodstream that exits the PTCA catheter, causing distal vessel wall trauma.

Regional flow adjusted hemoperfusion during coronary angioplasty: circulatory support/myocardial protection.

Routine percutaneous transluminal coronary angioplasty catheters are adequate and demonstrate high success rates in balloon angioplasty with stable patients. Active hemoperfusion seems to offer an advantage in patients with hemodynamic instability. Active hemoperfusion provides myocardial protection during coronary interventions and can be applied in conjunction with routine angioplasty equipment. When compared with other devices demonstrating clinical utility in a supported angioplasty setting, this flow adjustable active antegrade hemoperfusion pump appears reliable, simple to use, cost-effective, and requires much less instrumentation than the more bulky CPS systems.

Percutaneous transluminal coronary angioplasty catheters versus fluid-filled pressure monitoring guidewires for coronary pressure measurements and correlation with quantitative coronary angiography

The functional significance of a coronary stenosis can be assessed by measuring the translesional pressure gradient. Thirty-four patients were studied in the setting of percutaneous transluminal coronary angioplasty (PTCA) to evaluate the clinical relevance of the pressure gradient measurements by means of a PTCA balloon catheter. Both before and after PTCA, the mean pressure gradient across the stenosis was measured by means of a newly developed, 0.015-inch pressure-monitoring guidewire, first with only the wire across the stenosis (ΔP W, considered as the actual gradient), and second with the deflated balloon catheter advanced over the wire in the stenosis (ΔP b). Pressure gradients were correlated with quantitative coronary angiography of the stenotic segment. Before PTCA, mean ΔP b was larger than ΔP W (62 ± 14 vs 30 ± 20 mm Hg; p < 0.01). After PTCA, ΔP b remained systematically higher than ΔP W (23 ± 14 vs 3 ± 5 mm Hg; p < 0.01), despite a significant reduction of percent area stenosis from 84 ± 9 to 46 ± 17%, and an increase in minimal obstruction area from 0.98 ± 0.48 to 3.49 ± 1.32 mm 2. A significant correlation was found between ΔP W and percent area stenosis (r 2 = 0.66), with a marked increase after percent area stenosis reached 80%. The correlation between ΔP b and percent area stenosis was weaker (r 2 = 0.53), the scatter of the data was larger, and the inflection point of the curve was shifted toward less severe degrees of stenosis severity. The relation between the percent overestimation produced by the presence of the PTCA balloon catheter and either ΔP W or the ratio between catheter and obstruction cross-sectional area suggested that in intermediate lesions and post-PTCA segments, the overestimation was poorly predictable. Thus, the presence of a PTCA catheter through a coronary stenosis causes a systematic and unpredictable overestimation of the actual pressure gradient. Even after PTCA, the pressure gradient measured with the balloon catheter does not reflect the hemodynamic significance of the dilated segment.

A Rheolytic System for Percutaneous Coronary and Peripheral Plaque Removal

A method for plaque dissolution has been identified that percutaneously delivers a pulsatile high-velocity stream of saline to the site of an atheromatous lesion within a coronary or peripheral artery. In vitro evaluation and in vivo canine and porcine testing were performed using this 'rheolytic' system to determine its feasibility in ablating calcified plaque and soft thrombotic tissue. A prototype rheolytic guidewire capable of providing 30,000 psi of internal pressure was designed to fit within the guidewire lumen of a standard percutaneous transluminal coronary angioplasty catheter. An additional over-the-wire rheolytic catheter was fabricated to follow a standard .014-inch guidewire. The rheolytic devices were tested in vitro with simulated atheromatous and thrombotic lesions to evaluate the size and quantity of the particulate effluent. The particulate was then sterilized, mixed with saline, and introduced percutaneously into the animal kidney and heart for evaluation. The in vitro studies demonstrated that the rheolytic catheter and guidewire were able to follow both a coronary and femoral arterial model and successfully ablate the simulated lesions. The particle size for osseous, muscular, and cartilagenous tissue ranged from 2 to 6 micrometers; for fresh human plaque the particles ranged from 2 to 15 micrometers. Injection of cartilagenous and plaque particles into the animal model caused very slight regions of necrosis but no clinical sequelae. Applications of the rheolytic devices to the animal femoral artery demonstrated that both devices could ablate and cross calified or soft thrombosed lesions without damage to the vessel wall; the rheolytic catheter provided a debulking of the plaque.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary blood flow velocity during percutaneous transluminal coronary angioplasty as a guide for assessment of the functional result

To investigate the clinical usefulness of intracoronary Doppler recordings during percutaneous transluminal coronary angioplasty (PTCA), the changes of intracoronary blood flow velocity during PTCA were assessed in 20 patients with single proximal coronary stenosis, using a Doppler probe endmounted on the tip of a PTCA catheter. A mean of 4 inflations was performed in each patient. Intracoronary velocities were measured before and after each inflation and during peak reactive hyperemia after each transluminal occlusion. Quantitative analysis of the coronary stenosis was assessed before and after PTCA, and the dilatation resulted in an increase in minimal luminal cross-sectional area from 1.1 ± 0.8 to 2.7 ± 1.2 mm 2. A gradual and significant improvement in velocities was observed after the first 3 dilatations, but in 15 of the 20 patients the resting and hyperemic velocities were not affected by the fourth dilatation. Coronary flow reserve measured during reactive hyperemia after the last dilatation with the PTCA catheter across the lesion was 1.9. This value of coronary flow reserve is compatible with the residual stenosis measured after PTCA when corrected for the presence of the Doppler balloon catheter (0.68 mm 2). This application of the Doppler technique may provide a new method of on-line functional monitoring of the PTCA procedure in individual patients, but does not yet allow an accurate prediction of the change in coronary geometry brought about by PTCA.

Distal coronary power injection during percutaneous transluminal coronary angioplasty.

A modification of the standard percutaneous transluminal coronary angioplasty (PTCA) procedure is described using a power injector instead of a hand-held syringe for distal coronary contrast injections. This system was used in 215 dilatations without complications related to the power injector. We found this system to simplify the PTCA procedure and allowed for improved distal visualization even with the steerable PTCA catheters containing an intraluminal guide wire.