Skip to main content
  • Original Article
  • Open access
  • Published:

Application of first-generation high- and low-dose drug-coated balloons to the femoropopliteal artery disease: a sub-analysis of the POPCORN registry

Abstract

Background

Drug-coated balloons (DCBs) have significantly changed endovascular therapy (EVT) for femoropopliteal artery (FPA) disease, in terms of the expansion of indications for EVT for symptomatic lower extremity arterial disease (LEAD). However, whether there is a difference in the performance among individual DCBs has not yet been fully discussed. The present sub-analysis of real-world data from a prospective trial of first-generation DCBs compared the clinical outcomes between high- and low-dose DCBs using propensity score matching methods. The primary endpoint was the restenosis-free and revascularization-free rates at 1 year.

Results

We compared 592 pairs matched for patient and lesion characteristics using propensity score matching among a total of 2,507 cases with first-generation DCBs (592 and 1,808 cases in the Lutonix low-dose and In.PACT Admiral high-dose DCB groups, respectively). There were no differences in patient/lesion characteristics, procedural success rates, or complications between the two groups. First-generation low-dose DCB had significantly lower patency (73.3% [95% confidence interval, 69.6%–77.3%] in the low-dose DCB group versus 86.2% [84.1%–88.3%] in the high-dose DCB group; P < 0.001) and revascularization-free (84.9% [81.9%–88.1%] versus 92.5% [90.8%–94.1%]; P < 0.001) rates. Chronic kidney disease on dialysis, cilostazol use, anticoagulant use, and severe calcification had a significant interaction effect in the association (all P < 0.05).

Conclusions

EVT to FPA with first-generation DCBs had inferior low-dose patency outcomes as compared with high-dose outcomes in the present cohort.

Level of evidence

Sub analysis of a prospective multicenter study.

Peer Review reports

Background

Endovascular therapy (EVT) has been widely applied for symptomatic lower extremity arterial disease (LEAD) of the femoropopliteal artery (FPA) because of its less invasiveness, and it is supported by a large amount of evidence and guidelines [1,2,3]. With the understanding of the disease, lesion assessment, and technological innovations of the last decade, the EVT results in this area have dramatically improved. Particularly, drug-coated balloon (DCB) therapy has proven effective as a non-stenting treatment and has demonstrated good patency, benefiting many patients [4, 5]. The introduction of DCBs has greatly impacted this field, and a number of DCBs have entered the market. DCBs have several characteristics, including the type of drug and its dose, recipient, and balloon in which the drug is mounted. However, it is still unclear whether all DCBs will equally benefit the therapeutic strategy for FPA. The differences probably have a direct impact on the outcomes. Particularly, the amount of drug and recipient have been reported as important factors.

The POPCORN registry, a recent large-scale study of first-generation DCBs in real-world patient populations, reported that a multiple regression analysis identified several negative determinants of the loss of patency of DCB [6]. The use of low-dose DCB was one of the seven negative determinants. Drug doses in particular have also been an issue with concerns of increased mortality with paclitaxel, and it is still unclear which type or lesions or patient group it will affect [7]. Multiple regression analysis the current study aimed to compare the clinical outcomes between first-generation low- and high-dose DCBS for symptomatic FPA lesions, using the propensity score-matching method.

Method

Study population

The current study used a clinical database of the PrOsPective multiCenter registry Of dRug-coated ballooN for femoropopliteal disease (POPCORN) [6]. The POPCORN is an ongoing prospective multicenter observational study that registered adult patients (aged ≥ 20 years) undergoing DCB treatment for femoropopliteal lesions of symptomatic peripheral artery disease (Rutherford categories 2–5) [8] at 81 cardiovascular centers across Japan. Altogether, 2507 patients were registered between March 2018 and December 2019, and 5-year follow-ups have been scheduled. Only the following two first-generation DCBs were used in this study, because no other DCBs are commercially available: low- (Lutonix DCB, Bard, New Hope, MN, USA) and high-dose (IN.PACT Admiral, Medtronic, Santa Rosa, CA, USA) DCBs.

The study was conducted in accordance with the guidelines stipulated in the Declaration of Helsinki and was approved by the institutional review boards of the participating centers. Informed consent was obtained from the participants or, if not possible, from their families. The current study utilized the registry’s 1-year database. In patients with multiple FPA lesions treated, the first registered lesion was selected as their representative.

Outcome measures

The primary outcome measure was freedom from restenosis, which was compared between the first-generation high- and low-dose DCBs. Restenosis was defined as > 2.4 times of the peak systolic velocity ratio on duplex ultrasound or > 50% of the arterial diameter measured by angiography [9]. The secondary outcome measures included blood flow and severe dissection defined as grade D or severer [10] after DCB treatment, bailout stenting, postoperative ankle–brachial index (ABI), perioperative complication, freedom from reintervention, limb salvage rate, and overall survival.

Statistical analysis

Data on baseline characteristics are presented as the mean ± standard deviation (SD) and percentage for continuous and discrete variables, respectively, if not otherwise mentioned. A P value of < 0.05 was considered statistically significant, and 95% confidence intervals were reported where appropriate. The differences in baseline characteristics between the low-dose and high-dose DCB groups were crudely tested by the Welch’s t and chi-squared tests for continuous and discrete variables, respectively.

When the clinical outcomes were compared between the two groups, propensity score matching was adopted to minimize the intergroup difference in baseline characteristics. The propensity score was developed using the logistic regression model that included the following variables: age, sex, mobility, smoking, diabetes mellitus, renal function, chronic heart failure, medications, Rutherford classification, ankle–brachial index(ABI), aortoiliac revascularization, below-the-knee (BTK) runoff, history of revascularization, popliteal lesion, reference vessel diameter, lesion length, severe calcification (defined as peripheral artery calcification scoring system (PACSS) grade 4) [11], and chronic total occlusion. Matching was performed on the logit of the propensity score within the caliper of 0.2 SD. To maximize the statistical power to detect intergroup prognostic differences, we extracted as many matched samples in the high-dose DCB group to one in the low-dose DCB group as possible. After matching, the intergroup difference was analyzed with stratification by the pairs, and weighted descriptive statistics are reported. The intergroup balance in the baseline characteristics was assessed with the standardized difference. The proportions of perioperative outcomes were compared between the groups using the conditional logistic regression model. Time-to-events were estimated by using the Kaplan–Meier method and were compared between the two groups by the stratified log rank test. The interaction effect of the baseline characteristics on the association of DCB types with restenosis risk was analyzed using the Cox proportional hazards regression model stratified by the matched pairs. All statistical analyses were performed with R version 4.1.1 (R Development Core Team, Vienna, Austria).

Results

Among 2507 patients undergoing FPA EVT with DCB for symptomatic LEAD, 602 patients were treated with low-dose DCB, and the remaining 1905 patients were treated with high-dose DCB. The patients’ baseline characteristics are summarized in Table 1. The patient characteristics were generally similar between the two groups, with the exceptions of chronic kidney disease (CKD) and Rutherford category. The low-dose DCB group was more likely to have no BTK runoff, knee artery involvement, and severe calcification as compared to the high-dose DCB group. This difference may be due to the compatibility of the high- and low-dose DCBs with the 6- and 5-Fr sizes, respectively.

Table 1 Baseline characteristics of the study population before and after propensity score matching

During a median follow-up period of 14.2 (interquartile range, 10.323.0) months, restenosis was observed in 645 patients. The propensity score matching extracted 592 pairs (592 cases for the low-dose DCB group and 1808 cases in the high-dose DCB group), with no remarkable intergroup difference in baseline characteristics (Table 1). Table 2 shows the perioperative outcomes in the respective groups. There were no differences in post-EVT blood flow, severe dissection defined as grade D, post-procedure ABI, or procedure-related complications between the two groups. Bailout stent rates were significantly different; however, the rates were very low in both groups; thus, we believe that this difference has a little impact on the main objective of this analysis.

Table 2 Perioperative outcomes of the propensity score-matched population

Primary and secondary outcome measures

As shown in Fig. 1A and B, after the propensity score matching analysis, the low-dose DCB group had significantly lower rates of freedom from restenosis (73.3% [95% confidence interval, 69.6%–77.3%] in the low-dose DCB group versus 86.2% [84.1%–88.3%] in the high-dose DCB group; P < 0.001) and reintervention (84.9% [81.9%–88.1%] versus 92.5% [90.8%–94.1%]; P < 0.001) at 1 year. Limb salvage and overall survival rates were not significantly different between the two groups (both P > 0.05) (Fig. 1C and D). The interaction effect of the baseline characteristics with restenosis risk is shown in Fig. 2. CKD on dialysis, cilostazol use, anticoagulant use, and severe calcification had a significant interaction effect in the association (all P < 0.05); the restenosis risk of low-dose DCB versus high-dose DCB was significantly attenuated in the subgroups with those factors, as compared with the that of subgroups without those factors.

Fig. 1
figure 1

Freedom from restenosis (A), freedom from reintervention (B), limb salvage (C), and overall survival (D) in the matched population. Dotted lines indicate 95% confidence intervals. SE, standard error

Fig. 2
figure 2

Interaction effect of the baseline characteristics on the association of DCB types with restenosis risk in the matched population. Data are derived from the Cox proportional hazards regression model stratified by the matched pairs. Error bars indicate 95% confidence intervals

Discussion

This study compared the endovascular approach of FPA lesions for symptomatic LEAD using first-generation high- and low-dose DCBs. Propensity score matching analysis showed that high-dose DCBs performed better within the study period with statistical significance.

There are several explanations for this. The DCB is composed of three components (drug, recipient, and balloon). In addition to its characteristics, the operator selects the DCB that best suits the patient and lesion based on system size (0.014, 0.018, and 0.035 inch) and compatible sheath size (5 or 6 Fr), device diameter, and length.

Both DCBs used in this study were paclitaxel, but their drug-loading doses differed. In.PACT is classified as high-dose DCB (3.5 μg/mm-) and Lutonix as low-dose (2.0 μg/mm2). High-dose DCBs may be better for drug residuals in the vessel wall, whereas low-dose DCBs may be better for drug outflow distally. However, the increased mortality risk of paclitaxel devices is known to be independent of the drug dose [12]. Moreover, it the slow flow phenomenon caused by the drug is not associated with worsening chronic limb threatening ischemia (CLTI) [13]. Currently, there is no evidence that high-dose DCBs increase the safety risks, as compared to low-dose DCBs, except for a few small case studies [14, 15].

The results of a recent randomized trial comparing a first-generation high-dose DCB to a second-generation low-dose DCB (Ranger Paclitaxel-Coated PTA Balloon Catheter, Boston Scientific, Marlborough, MA, USA) did not report any difference in the patency outcomes [16]. Ranger DCBs is classified as low-dose DCBs with a drug dose of 2.0 μg/mm2, similar to LUTONIX, but it has an improved recipient TransPax technology, which allows the drug to remain in the vessel wall longer [17]. In other words, the key factor in DCB is the drug amount, but with recipient, even a small amount of drug may be expected to have a greater effect.

Next, the present study confirms that first-generation low-dose DCB is inferior to high-dose DCB on a non-case basis. We evaluated whether the results of the main analysis were independent of case and lesion characteristics using an interaction analysis.

The interaction analysis revealed several interesting points. Although most parameters showed the advantage of the high-dose DCB, the following parameters showed no difference between the high and low-dose DCBs, in the rates of renal failure on dialysis, cilostazol usage, anticoagulant usage, and severe calcification. Renal function and dialysis patients are known to have a high rate of calcification [18], and DCB has been reported to be ineffective for severe calcification [19]. This suggests that both groups had poor outcomes. However, the individual subgroups have smaller sample sizes than the overall population. Therefore, it remains unclear whether there is really no difference or if the small sample size prevents us from obtaining a significant difference. In other words, it is inconclusive whether low-dose DCB is equivalent to high-dose DCB for dialysis, cilostazol, anticoagulants, and PACSS 4 severe calcification. The only thing that can be said about the interaction analysis is that the degree of the inferiority of the low-dose DCB relative to the high-dose DCB is significantly smaller in the subgroup with these four parameters than in the subgroup without these factors. Conversely, in the subgroup without these four factors, the hazard ratio in Fig. 2 is significantly > 1.0. However, there is no guarantee that the low- and high-dose DCB groups are perfectly matched in these subgroups (they are matched only in the total number of cases); thus, we cannot be sure whether this is truly a sign of inferiority of the low-dose DCB group or whether the bias in the low-dose DCB group is associated with an increased risk of restenosis. This is the limiting factor in this study.

Conclusions

In this study cohort, first-generation low-dose DCB had a significantly lower restenosis-free (73.3% [95% confidence interval, 69.6% to 77.3%] in the low-dose DCB group versus 86.2% [84.1% to 88.3%] in the high-dose DCB group; P < 0.001) and revascularization (84.9% [81.9% to 88.1%] versus 92.5% [90.8% to 94.1%]; P < 0.001) rates than the first-generation high-dose DCB. Some interaction factors were also observed, but these factors need to be examined in more detail in future studies.

Availability of data and materials

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Abbreviations

EVT:

Endovascular therapy (EVT)

LEAD:

Lower extremity arterial disease (LEAD)

FPA:

Femoropopliteal artery (FPA)

DCB:

Drug-coated balloon (DCB)

BTK:

Below-the-knee (BTK)

CLTI:

Chronic limb-threatening ischemia (CLTI)

ABI:

Ankle-brachial index (ABI)

PACSS:

Peripheral artery calcification scoring system (PACSS)

References

  1. Farhan S, Enzmann FK, Bjorkman P, Kamran H, Zhang Z, Sartori S, et al. Revascularization strategies for patients with femoropopliteal peripheral artery disease. J Am Coll Cardiol. 2023;81:358–70. https://doi.org/10.1016/j.jacc.2022.10.036.

    Article  PubMed  Google Scholar 

  2. Gunnarsson T, Bergman S, Pärsson H, Gottsäter A, Lindgren H. Long term results of a randomised trial of stenting of the superficial femoral artery for intermittent claudication. Eur J Vasc Endovasc Surg. 2023;65:513–9. https://doi.org/10.1016/j.ejvs.2023.01.004.

    Article  PubMed  Google Scholar 

  3. Aboyans V, Ricco JB, Mel B. 2017 ESC guidelines on the diagnosis and treatment of peripheral arterial diseases, in collaboration with the European Society for Vascular Surgery (ESVS): document covering atherosclerotic disease of extracranial carotid and vertebral, mesenteric, renal, upper and lower extremity arteries endorsed by: the European stroke organization the task force for the diagnosis and treatment of peripheral arterial diseases of the European Society of Cardiology (ESC) and of the European Society for Vascular Surgery (ESVS). Eur Heart J. 2018;39:763–816.

    Article  PubMed  Google Scholar 

  4. Micari A, Brodmann M, Keirse K, Peeters P, Tepe G, Frost M, et al. Drug-coated balloon treatment of femoropopliteal lesions for patients with intermittent claudication and ischemic rest pain: 2-year results from the in.pact global study. JACC Cardiovasc Interv. 2018;11:945–53. https://doi.org/10.1016/j.jcin.2018.02.019.

  5. Rosenfield K, Jaff MR, White CJ, Rocha-Singh K, Mena-Hurtado C, Metzger DC, et al. Trial of a paclitaxel-coated balloon for femoropopliteal artery disease. N Engl J Med. 2015;373:145–53. https://doi.org/10.1056/NEJMoa1406235.

    Article  CAS  PubMed  Google Scholar 

  6. Soga Y, Takahara M, Iida O, Tomoi Y, Kawasaki D, Tanaka A, et al. Vessel patency and associated factors of drug-coated balloon for femoropopliteal lesion. J Am Heart Assoc. 2023;12:e025677. https://doi.org/10.1161/JAHA.122.025677.

  7. Katsanos K, Spiliopoulos S, Kitrou P, Krokidis M, Karnabatidis D. Risk of death following application of paclitaxel-coated balloons and stents in the femoropopliteal artery of the leg: A systematic review and meta-analysis of randomized controlled trials. J Am Heart Assoc. 2018;7:e011245. https://doi.org/10.1161/JAHA.118.011245.

  8. Rutherford RB, Becker GJ. Standards for evaluating and reporting the results of surgical and percutaneous therapy for peripheral arterial disease. J Vasc Interv Radiol. 1991;2:169–74. https://doi.org/10.1016/s1051-044372275-6.

    Article  CAS  PubMed  Google Scholar 

  9. Patel MR, Conte MS, Cutlip DE, Dib N, Geraghty P, Gray W, et al. Evaluation and treatment of patients with lower extremity peripheral artery disease: consensus definitions from peripheral academic research consortium (PARC). J Am Coll Cardiol. 2015;65:931–41. https://doi.org/10.1016/j.jacc.2014.12.036.

    Article  PubMed  PubMed Central  Google Scholar 

  10. Fujihara M, Takahara M, Sasaki S, Nanto K, Utsunomiya M, Iida O, et al. Angiographic dissection patterns and patency outcomes after balloon angioplasty for superficial femoral artery disease. J Endovasc Ther. 2017;24:367–75. https://doi.org/10.1177/1526602817698634.

    Article  PubMed  Google Scholar 

  11. Rocha-Singh KJ, Zeller T, Jaff MR. Peripheral arterial calcification: prevalence, mechanism, detection, and clinical implications. Catheter Cardiovasc Interv. 2014;83:E212–20. https://doi.org/10.1002/ccd.25387.

    Article  PubMed  Google Scholar 

  12. Rocha-Singh KJ, Duval S, Jaff MR, Schneider PA, Ansel GM, Lyden SP, et al. Mortality and paclitaxel-coated devices: an individual patient data meta-analysis. Circulation. 2020;141:1859–69. https://doi.org/10.1161/CIRCULATIONAHA.119.044697.

    Article  PubMed  PubMed Central  Google Scholar 

  13. Hata Y, Iida O, Ito N, Soga Y, Fukunaga M, Kawasaki D, et al. Roles of angioplasty with drug-coated balloon for chronic ischemia in wound healing. J Endovasc Ther. 2021;28:778–87. https://doi.org/10.1177/15266028211025023.

    Article  PubMed  Google Scholar 

  14. Boitet A, Grassin-Delyle S, Louedec L, Dupont S, Lamy E, Coggia M, et al. An experimental study of paclitaxel embolisation during drug coated balloon angioplasty. Eur J Vasc Endovasc Surg. 2019;57:578–86. https://doi.org/10.1016/j.ejvs.2018.11.019.

    Article  PubMed  Google Scholar 

  15. Torii S, Jinnouchi H, Sakamoto A, Romero ME, Kolodgie FD, Virmani R, et al. Comparison of biologic effect and particulate embolization after femoral artery treatment with three drug-coated balloons in healthy swine model. J Vasc Interv Radiol. 2019;30:103–9. https://doi.org/10.1016/j.jvir.2018.07.025.

    Article  PubMed  Google Scholar 

  16. Steiner S, Schmidt A, Zeller T, Tepe G, Thieme M, Maiwald L, et al. Low-dose vs high-dose paclitaxel-coated balloons for femoropopliteal lesions: 2-year results from the compare trial. JACC Cardiovasc Interv. 2022;15:2093–102. https://doi.org/10.1016/j.jcin.2022.08.004.

    Article  PubMed  Google Scholar 

  17. Yoshikawa M, Torii S, Aihara K, Ito M, Nakamura N, Noda S, et al. Differences in biologic drug effects and distal particulate embolization in three paclitaxel-coated balloons for femoropopliteal lesions in a rabbit. J Endovasc Ther. 2023;15266028231161215. https://doi.org/10.1177/15266028231161215.

  18. Fujihara M, Kozuki A, Tsubakimoto Y, Takahara M, Shintani Y, Fukunaga M, et al. Lumen gain after endovascular therapy in calcified superficial femoral artery occlusive disease assessed by intravascular ultrasound (CODE Study). J Endovasc Ther. 2019;26:322–30. https://doi.org/10.1177/1526602819836095.

    Article  PubMed  Google Scholar 

  19. Fanelli F, Cannavale A, Gazzetti M, Lucatelli P, Wlderk A, Cirelli C, et al. Calcium burden assessment and impact on drug-eluting balloons in peripheral arterial disease. Cardiovasc Intervent Radiol. 2014;37:898–907. https://doi.org/10.1007/s00270-014-0904-3.

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

The authors would like to thank the participants for their involvement in this study. The authors also thank Drs. Akiko Tanaka, Yasutaka Yamauchi, Kazuki Tobita, Amane Kozuki, Motoi Kushibki, Naoki Hayakawa, Shuichi Seki, Hideaki Otsuji, Makoto Sugihara, Yuki Imoto, Masato Taniguchi, Yasunori Arai, Yo Iwata, Tai Kojima, Tsuyoshi Shibata, Yoshitane Seino, Hirofumi Kurokawa, Toru Mazaki, Takashi Uemura, Yusuke Miyashita, Yukako Ogoyama, Toru Hasegawa, Shinya Okazak, Taketsugu Tsuchiya, Hideo Tokuyama, Atsushi Tosaka, Taku Toyoshima, Yuhei Yamaji, Hideki Doi, Tomokazu Ikemoto, Takenobu Shimada, Hiroyuki Tanaka, Yasuaki Takeji, Hiroki Kondo, Terutoshi Yamaoka, Eiji Kojima, Kenji Ogata, Takashi Miura, Tomoaki Mochidomem, Kensaku Higashi, Koji Hozawa, Koki Ohmi, Toshinobu Ishikawa, Nobuo Kato, Takahito Itoh, Hironobu Toda, Jun Nakazato, Kuniyoshi Fukai, Tatsuya Shiraki, Yunosuke Nishihara, Nobuhiro Suematsu, Eiji Taguchi, Shinsuke Mori, Takuya Haraguchi, Hiroaki Tsujita, Kazuki Haraguchi, Tamon Kato, Norihiro Shimizu, Seiji Matsuhisa, Soichiro Enomoto, Junichiro Takaoka, Tatsuro Takei, Makoto Utsunomiya, Kenichiro Yuba, Kenji Suzuki, Tatsuya Nakama, Naotaka Murata, Michinao Tan, Tomohiro Arakaki, Ryoji Koshida, Hideaki Aihara, Tomoyuki Kawashima, Hyuuma Daidouji, Hiroki Takahashi, Taku Shikama, Tatsuki Doijiri for enrolled participants. And the cardiac catheterization laboratory staffs (Tomofumi Tsukizawa MD, Yuko Yazu CE, at Kishiwada Tokushukai Hospital) and clinical research coordinators of the participating centers (Kenji Nakatani at Kishiwada Tokushukai Hospital).

Funding

The POPCORN study was supported by the Research Association for Lower Limb Artery Revascularization (LIBERAL).

Author information

Authors and Affiliations

Authors

Contributions

Drs. Soga, Iida, Kawasaki and Fujihara planned, organized, and conducted this study. Determined the clinical study. Dr. Fujihara wrote the article. Dr. Takahara performed statistical analysis. The other authors provided treatment and registered. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Masahiko Fujihara.

Ethics declarations

Ethics approval and consent to participate

The study was conducted in accordance with the guidelines stipulated in the Declaration of Helsinki, and was approved by the institutional review boards of the participating centers. Informed consent was obtained from the participants or, if not possible, from their families.

Consent for publication

Written consent was obtained from the patient.

Competing interests

Drs Soga and Iida received honoraria from BARD Japan and Medtronic Japan. Dr. Fujihara received honoraria from Medtronic Japan. The remaining authors have no disclosures to report.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Fujihara, M., Takahara, M., Soga, Y. et al. Application of first-generation high- and low-dose drug-coated balloons to the femoropopliteal artery disease: a sub-analysis of the POPCORN registry. CVIR Endovasc 6, 41 (2023). https://doi.org/10.1186/s42155-023-00390-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s42155-023-00390-x

Keywords