Since 1996 our electrophysiological diagnostic catheters and ablation catheters have been submitted to a certified (DIN EN ISO 13485) reprocessing company (Remed GmbH®, a member of the VANGUARD group). Each step of reprocessing that the catheters have to pass is certified according to the existing international regulations (standards, guidelines, etc.), which is required by law in Germany1,2 and is in accordance with EU laws and guidelines. These regulations demand that reprocessed medical devices have the same safety and performance levels as new products. All processes are included in the quality management of the company and the hospital.
The manufacturing industry had repeatedly claimed that the reuse of catheters could have serious disadvantages for patients, or that the reprocessing of such devices represented an unbearable risk. We therefore decided to evaluate the potential risks of reused products in clinical electrophysiology in a prospective registry in 2000 and 2003. The registry was in the scope of our quality management system; ablations were performed using new ablation and diagnostic catheters as well as catheters reprocessed by an industrial partner. The aim of the study was to detect potential differences between both lines in terms of risks and procedural outcome in patients.
It could be assumed that reprocessing would alter the properties of the material or the function of the catheter in such a way that the examination might become more difficult, which in turn would result in a deterioration of various specific performance parameters. For example, changes in the torque and push stability of a catheter could lead to placement difficulties, meaning that the duration of the examination and fluoroscopy time would be increased compared with new catheters. If the tip electrode of the catheter cannot be placed in a stable position on the endocardial point of intended ablation, numbers of radiofrequency (RF) deliveries may increase. Based on these considerations, we assessed 202 catheter interventions in patients, in whom about an equal number of new electrophysiological catheters and catheters that had been reprocessed were used. The register was prospective. Samples were drawn at consecutive days by a non-medical responsible technician. Reused catheters were drawn without any preselection from the hospital storage out of 356 available recycled and 298 new catheters. The number of reprocessing turns (one to six times) was read from the barcode of the catheter and entered into the data collection sheet after an ablation procedure was finished. This number was unknown to the sample-drawing technician and the medical doctor responsible for the procedure.
There are some limitations to the study, to be mentioned below. The reported data are part of a quality management register of both VANGUARD and the Kerckhoff-Klinik Bad Nauheim. The study should not be considered randomised. The technician collecting the samples was independent and unaware of the success of the ablation, any difficulties encountered during the procedure or late results of the six-month follow-up. The medical doctors examining the patients at follow-up did not know whether the patients had been treated with new or reused catheters. The follow-up investigations were part of a quality-control programme conducted by the Kerckhoff-Klinik Bad Nauheim, the cardiology department of the University of Frankfurt and the medical services of statutory health insurance bodies in the federal state of Hesse (MDK Hesse), Germany. The results regarding complications and success rates of RF-energy ablation of arrhythmias were audited by a sample-drawing medical doctor from MDK Hesse. It must be emphasised that testing the use of new or reprocessed catheters was not the primary goal of this quality management contract, but it may reflect steps to ISO 9001. Investigations with a multicentre, randomised study controlled by EU or German independent certifying authorities are desirable to deliver further results.
The following specific parameters (primary end-points of the registry) were recorded and assessed for a total of 202 patients:
- procedure time (min);
- fluoroscopy time (min);
- number of RF energy deliveries (n);
- severe procedure-related complications – pericardial effusion or tamponade, third-degree atrioventricular (AV) block, peri-procedural thromboembolic event or intention to treat related death; and
- recurrence of arrhythmia during the first six months after ablation.
The procedure time was calculated from the moment the patient was placed on the examination table to the retransferral of the patient after the procedure. The fluoroscopy time refers to the duration of the necessary X-ray fluoroscopy carried out in order to perform the catheter ablation. A further important parameter recorded was the number of RF energy deliveries for each intervention, which is a marker of catheter stability at the location of ablation. Procedure-related complications were picked up over a time period of six months. For the statistical analysis of continuous variables, for unpaired samples a t-test was used and for categorical variables Fischer’s exact p was used. All values are given as mean. The differences were considered as significant by an error probability of 5%. Statistical testing was performed for the whole sample because subgroups of different procedures were too small and too imbalanced for statistical purposes.
Table 1 shows that the register covered different types of diagnosis, such as atrial fibrillation, atrial flutter, Wolfe-Parkinson-White syndrome (WPW) and atrioventricular nodal re-entry tachycardia (AVNRT). In the group of patients treated with reprocessed catheters, 241 catheters were used. The respective number for patients treated with new catheters was 231. Reprocessed catheters consisted of units that had been reprocessed up to six times (see Figure 1).
In Figure 2, the results of all 202 patients are given as the mean value for reused and new catheters. The given parameters – procedure time, fluoroscopy time and number of RF energy deliveries – did not differ significantly in the total cohort of patients. It is apparent that the ablation procedure was not influenced by the use of reprocessed diagnostic or ablation catheters. It must be considered that the results are derived from different diagnoses, different anatomical features and different medical doctors. Figure 3 provides mean values for a complex ablation procedure such as the left atrial ablation of atrial fibrillation; other figures show results for easier procedures such as atrial flutter ablation (see Figure 4), WPW ablation (see Figure 5) and AVNRT ablation (see Figure 6). Imbalances in the subgroups were too high for statistical testing.
In follow-up examinations, the recurrences of arrhythmia or complications up to discharge and after a period of six months were recorded for the reused catheters (see Figure 7) and new catheters (see Figure 8) for the various procedure types. One third-degree AV block occurred during slow pathway ablation in a patient with AVNRT using a new catheter. One pericardial effusion without necessity of puncture occurred during a left atrial ablation of atrial fibrillation using reprocessed catheters. The numbers of complications were in the normal ranges for the procedures performed. In particular, unexplained fever and septic complications – which might be related to residual proteins – did not occur with either new or reprocessed products. No intention to treat related death or thromboembolic event occurred in either of the groups.
The number of early recurrences (during hospitalisation) after ablation using new catheters were 3/100 patients, and 4/100 patients at the six-month follow-up. The results for reprocessed catheters were 4/102 early recurrences and 2/102 at follow-up. Therefore, recurrences during follow-up were observed in 7% of patients using new catheters versus 6.9% of those using reprocessed catheters: again, there was no significant difference (see Table 2).
Results From 2000 Verified
These results confirmed the data gained from a similar comparative – but smaller – study that we performed in 2000.3 In the 2000 study we assessed the specific parameters of examinations carried out on a total of 110 patients. Fifty patients had been treated with reprocessed catheters and 60 patients with new ones. The results of this study are shown in Figure 9. From the mean values obtained for all examinations – i.e. without consideration of the type of diagnosis – it was found that almost identical results were obtained for reprocessed ablation catheters with respect to the duration of the procedure, fluoroscopy time and the number of RF-energy deliveries. The later study thus verifies these results.
External Results From Another Centre (Schüchtermann Clinic)
In 2000, the Schütermann Clinic also decided to install internal quality management for the control of reprocessed medical devices primarily designed for ‘single use’. Similar comparative studies were performed in Bad Rothenfelde in 2000 to assess diagnostic and interventional cardiocatheter examinations.4,5 One thousand consecutive interventions using new and reprocessed diagnostic catheters, guiding catheters and percutaneous transluminal coronary angioplasty (PTCA) catheters were evaluated. The results match our experience – i.e. no significant differences were found between catheters that were used just once and catheters that were reused after reprocessing by a professional reprocessor (VANGUARD).
Although our data presentation includes the limitations outlined above, the quality management processes of VANGUARD and our clinic did not find any obvious risks in the reprocessing of high-quality electrophysiological catheters from the major manufacturers. The reason for this is that the quality of new catheters has improved dramatically since the beginning of the 1980s. This is a result of the growing market for interventional electrophysiology, improved internal quality management at the manufacturers and the increasing safety and effectiveness controls installed by governments in and outside the US.
The desire to sell single-use catheters is understandable when one considers development costs, regulatory risks and further financial interest. However, there is a conflict of interests here. Societies want to offer optimal medical treatment to all those who need it, as safely as possible and at a price that can be covered by that country’s economic power. Opponents of reprocessing repeatedly claim that the reprocessing of single-use medical devices bears an increased risk, and that the safety and health of patients is thus endangered. However, our results show that this is not the case. Material changes that occur during the course of preceding applications and reprocessing seemed to be clinically irrelevant and influence neither the course of the procedure nor late results. This means that the high quality provided by the original equipment manufacturers allows the treatment of a larger number of patients who ask for optimal treatment of their disease.
Reprocessing By a Certified Reprocessor
The prerequisite for excellent results is that reprocessing is performed at a high standard, comparable to the quality management of original equipment manufacturers. The decisive factor is that the safety goals defined in the Medizinproduktegesetz (MPG – German Medical Devices Act) and the Medizinprodukte-Betreiberverordnung (MPBetreibV – German Medical Devices Operator Ordinance) are maintained, and that the reuse of a ‘single-use’ device does not lead to an increased risk for the patient. This should be controlled by the quality management of each hospital using reprocessed products as well as by the reprocessing company. A merged quality management is desirable. Section 4 of the MPBetreibV establishes the joint recommendations made by the Kommission für Krankenhaushygiene und Infektionsprävention (German Commission for Hospital Hygiene and Infection Prevention) at the Robert-Koch Institute and the Bundesinstitut für Arzneimittel und Medizinprodukte (German Federal Institute for Pharmaceuticals and Medical Devices) regarding the hygiene requirements for the reprocessing of medical devices (RKI-Guideline).6
This guideline is therefore not only a recommendation, but has become a legal obligation. In this directive, which does not differentiate between singleuse and multiple-use medical devices, medical devices declared as being for single use are to be assigned to the category ‘Critical medical devices with particularly high requirements for reprocessing’ (Critical C). The legislator has thus also introduced safety standards for reprocessing ‘single-use’ medical devices, and these safety standards are comparable to those that are applicable to manufacturers placing medical devices on the market for the first time. At this time, in our experience only VANGUARD meets all of the requirements specified by the RKI-Guideline with respect to the reprocessing of Critical C medical devices. The required quality management system in compliance with DIN EN ISO 134857 is already in place. Furthermore, certification supplements prove that the requirements of the RKI-Guideline as well as those of EN 5508 are being complied to. A special identification system makes it possible to provide such evidence on a patient-related basis as well.
The comparative registers we have performed in-house provide a decisive supplement to the risk management and control systems of the reprocessor that meets the required level. An important point in the reuse of so-called ‘single-use’ devices is the question of the assumption of liability. Because the manufacturer’s product liability expires after the first application, it is very important that the reprocessor takes over contractual liability corresponding to the initial product liability; this must be covered by an adequate level of insurance on the part of the reprocessor.
Volumes Reprocessed 1996–2003
Meanwhile, VANGUARD can look back on several years of experience with reprocessed catheters. From the end of 1996 to 2003, a total of 19,400 diagnostic and ablation catheters were forwarded for reprocessing and, following in-depth product testing, approximately 15,800 of these devices were released for reuse by VANGUARD (see Figure 10). On average, 18.5% of the ablation catheters forwarded for reprocessing were scrapped by quality assurance. The external company subjects each device to a series of tests. These tests include a visual inspection using a magnifying glass or a microscope to ensure cleanliness and the integrity of the surfaces. Catheters with kinks, surface impairments or any other damage are not released for reprocessing. Important aspects are the electrical function tests performed on the individual poles and checks on the thermistors and the thermocouplers.
Controllability and the curvature form are also routinely inspected. As soon as a device shows any deficiencies, it is scrapped. Figure 11 shows the most frequent reasons for scrapping. With ablation catheters, by far the largest proportion of scrapping is due not to any special deficiencies, but to the fact that the respective devices have reached their maximum permissible reprocessing frequency (approximately 5.6% of the total unit numbers). Based on the results of validation examinations, this number is limited to six for electrophysiological ablation and diagnostic catheters – i.e. when a catheter is forwarded for reprocessing for the seventh time, it is automatically scrapped. When this frequency of reprocessing is used, tests performed by qualified specialist institutes found no changes to the material, hygienic and functional capabilities of the devices that could represent any increased risk for the patient, the user or any third party.
The most frequent defects or restrictions found in the devices were surface impairments, thermistor defects, thermocouple defects and deformations of the curve. An extensive documentation system performed by the reprocessor serves to provide a basis upon which the user can, within the framework of its obligation to perform due care and its accountability, provide evidence at any time of the functional and hygienic integrity of the catheters on a patient level and for each and every individual device.
Figure 12 shows the distribution of reprocessing frequencies for the total number of catheters forwarded by us during the period 1996–2003. The figure also shows that the percentage scrap quota continually drops from the first to the fifth cycle. This shows that those catheters that are reprocessed several times had a good quality. Only during the sixth cycle did the quota rise markedly again. When the seventh cycle arrived, no catheter was released for further reprocessing, because the maximum specified number of cycles had been reached. Experience has shown that the greatest proportion of catheters can be reprocessed without difficulty, so that good corresponding savings are achieved.
A comparison between new catheters used for the first time and catheters that have been reprocessed up to six times shows that neither the material properties nor the functional characteristics of the devices have suffered due to reprocessing. The course of the examination of the patient is not rendered more difficult due to the multiple reuses of ablation catheters, and no higher frequency of complications was observed. It can thus be stated that the reuse of reprocessed catheters does not result in any disadvantages for the patient or the user. No signs of an increased risk to the patient were found. An important prerequisite for the safety of patients is the merging of intra-hospital quality management with the quality management of the reprocessing company. All processes on both sides should be clear, transparent and documented.
For the future, it would be desirable to support the described experiences with further prospective and randomised comparative studies regulated and controlled by independent governmental institutions.
Reproduced with permission from the European Association for Medical Device Reprocessing.