NN&I - August 2010

Vascular Access 32 Nephrology News & Issues August 2010Subscribe to our free eNewsletter at www.nephronline.com HeRO device since the product became available for clinical use. The total duration of HeRO device use in this patient survey population was 348.4 months for an average of 5.4 months per patient (range 0.1 to 16.5 months). Figure 3 shows a breakdown of the duration of use of the HeRO device for the entire survey population. Fifty-three of the 65 patients (81.5%) were still dialyzing via the HeRO device at the time of the survey. Of the remain -ing HeRO patients, five were deceased (7.7%) as a result of non-device related events, and seven patients (10.8%) were dialyzing via another vascular access option. Causes for device removal includ-ed occlusion (n=3), infection (n=1), steal syndrome (n=1), low arterial flow (n=1), and patient choice associated with hospice care (n=1). The average duration of HeRO device use was 6.0 months for patients who had the device removed and 8.6 months for deceased patients. The dialysis providers sur -veyed reported that 38 of the patients (58.5%) included in the survey did not experience any performance-related issues with the HeRO device. There were 28 device performance issues in the remaining 27 patients included in the survey (see Table 3). Occlusion was the single most com-monly reported performance issue, with 18 patients (27.7%) experiencing 25 occlusive episodes. The majority of the patients who had occlusion only experienced one occlusive event (see Figure 4). When occlusions occurred, they were typically early, with aver -age time for the development of the first occlusive event (when known) of 2.7 months (see Figure 5). Hypotensive episodes, the most common precipitat -ing cause of occlusion, were reported for 22% of patients who had occlusive events. Device removal for occlusion occurred in three patients. Infections occurred in four of the 65 patients included in the survey (6.2%), resulting in an overall infection rate of 0.38 per 1,000 patient days. Discussion This post-market surveillance survey confirmed that the rate of performance issues associated with the HeRO device was no greater than what was reported in the initial clinical registration stud -ies for the device. Occlusions, which are the most prevalent adverse event associated with dialysis grafts, was also the most commonly reported device-related event experienced by patients using the HeRO device in this survey, occurring in 27.7% of the patients. This rate of occlusion is less than the 58% of HeRO patients and 45% of stan-dard AV graft patients who had at least one occlusive episode during the ini -tial prospective, multi-center random-ized clinical trial comparing the HeRO device to conventional ePTFE grafts. A more recent report from a single-center retrospective study noted an occlusion rate of 19.2% for the HeRO device with a mean time to first occlusion of 150 days (range 51 to 321 days).4There are several potential avoid -able causes of occlusions in HeRO patients (see Table 4). Taking proper precautions to reduce these risks when possible is important in maintaining adequate blood flow through the HeRO device and in preventing the need for thrombectomy procedures. While four HeRO device patients included in this survey were report -ed to have developed infections, this FIGURE 4 Three occlusions 1.5% Two occlusions 7.7% 47 patients 12 patients 5 patients One occlusive 18.5% No occlusive events 72.3% 1 patientFrequency of occlusive events FIGURE 5 0 0 10Number of clotting episodesTiming in weeks post-implant 20 30 40 1 2 3 4 5Average time for the development of the first occlusive event FIGURE 3 >12 months 9.2% 6 to 12 months 23.1% 0 to 6 months 30.8% 3 to 6 months 36.9%Duration of use of HeRO device for the entire survey population VascularAccess_0810_14.indd 32 7/16/10 3:36:43 PM