- Email: [email protected]
Bypass versus angioplasty in severe ischaemia of the leg
Correspondence
In the BASIL trial,1 outcomes after bypass surgery and balloon angioplasty were compared in patients with rest pain, ulceration, and gangrene of the leg (severe limb ischaemia). The investigators state that the extent of the lesion that had been bypassed at surgery and recannalised by angioplasty was similar. However, other critically important angiographic findings were not mentioned. Which were the arterial lesions, stenoses, or occlusions? What were the morphological classifications of the lesions on the basis of TransAtlantic Inter-Society Consensus (TASC)2 definitions? According to a study of percutaneous infrainguinal arterial angioplasty for treatment of chronic limb-threatening ischaemia (rest pain, gangrene, or non-healing ulcers),3 technical failure correlated with TASC D lesions and the presence of occlusion, and major amputation correlated with the combination of arterial occlusion, diabetes, and gangrene. In the BASIL trial, consultant vascular surgeons and interventional radiologists were asked to consider all patients who, on diagnostic imaging, had a pattern of disease which, in their joint opinions, could equally well be treated by either infrainguinal bypass surgery or balloon angioplasty. There were significant differences, however, between surgeons and radiologists with regard to how angiographic variables determined treatment preferences.4 Did the joint opinions of surgeons and radiologists in the BASIL trial consider arterial occlusions or TASC D lesions to be treated equally well by either strategy? Previous studies comparing the clinical effectiveness and costeffectiveness of the two strategies for various degrees of lower limb ischaemia have had limitations5 such as lack of controls; small numbers of patients; poorly defined patients and interventions; inclusion, comparison, and combined analysis of patients with intermittent claudication and www.thelancet.com Vol 367 June 3, 2006
severe limb ischaemia as well as with aortoiliac and infrainguinal disease; retrospective analysis; and short or incomplete follow-up.1 If the abovementioned angiographic findings are not disclosed, the BASIL trial cannot be level 1 evidence any more than the previous studies because of poorly defined arterial lesions. We declare that we have no conflict interest.
*Hisato Takagi, Maiko Furukawa, Takayoshi Kato, Yukihiro Matsuno, Takuya Umemoto [email protected] Department of Cardiovascular Surgery, Shizuoka Medical Centre, 762-1 Nagasawa, Shimizu-cho, Sunto-gun, Shizuoka 411-8611, Japan 1
2
3
4
5
Adam DJ, Beard JD, Cleveland T, et al. Bypass versus angioplasty in severe ischaemia of the leg (BASIL): multicentre, randomised controlled trial. Lancet 2005; 366: 1925–34. Dormandy JA, Rutherford RB. Management of peripheral arterial disease (PAD): TransAtlantic Inter-Society Consensus (TASC). J Vasc Surg 2000; 31: S1–296. Tefera G, Hoch J, Turnipseed WD. Limb-salvage angioplasty in vascular surgery practice. J Vasc Surg 2005; 41: 988–93. Bradbury A, Wilmink T, Lee AJ, et al. Bypass versus angioplasty to treat severe limb ischemia: factors that affect treatment preferences of UK surgeons and interventional radiologists. J Vasc Surg 2004; 39: 1026–32. Bradbury AW. Angioplasty is the first line treatment for critical limb ischaemia: the case against. In: Greenhalgh RM, ed. Vascular and endovascular controversies. London: BIBA Publishing, 2003: 295–307.
Author’s reply Although not the primary objective of the study, the serious shortcomings identified in the pretrial medical management of these highest risk vascular patients were so striking that we felt they deserved specific inclusion and comment in our paper. Numerous studies, including those from our own group, as well as Lloyd Bradley and Stephen Kirker’s own survey, have shown that the medical treatment of patients with peripheral arterial disease (PAD) is much less satisfactory than that generally received by those with coronary artery disease. The reasons for this finding are complex and multifactorial. However, they probably include a less well-developed evidence base with respect to PAD
and, with respect to the UK, cost pressures, the absence of a National Service Framework for PAD, and the lower priority given to PAD in the new general practitioner contracts. The outlook for patients with severe limb ischaemia is extremely poor almost irrespective of what treatment is received. As such, much greater effort should be made and resources expended to identify and treat, predominantly medically, PAD at a much earlier stage so that the progression to severe limb ischaemia can be prevented or at least retarded. Best medical therapy is also likely to improve the safety and durability of surgical and endovascular interventions for severe limb ischaemia once it has developed. I can reassure Hisato Takagi and colleagues that copies of all pretreatment imaging data, which in most cases were intra-arterial digital subtraction angiograms, are being collated centrally and scored independently by two consultant interventional radiologists who are unaware of treatment allocation. As Takagi and colleagues quite rightly point out, these additional data will be important in confirming (as one would expect in a multicentre randomised controlled trial) that the patterns of disease being treated in the two groups of the trial were similar, and in helping to define with more precision which types and patterns of disease are best suited to either balloon angioplasty or bypass surgery. Takagi and colleagues make reference to our earlier work in which we used Delphi consensus methods to showed that, before the BASIL trial, there was little agreement between and among vascular surgeons and interventional radiologists about the relative merits of balloon angioplasty and bypass surgery for severe limb ischaemia secondary to a wide range of different angiographic scenarios. Once all the data from the BASIL trial have been published and digested, we intend to repeat the Delphi studies to 1815
In the BASIL trial,1 outcomes after bypass surgery and balloon angioplasty were compared in patients with rest pain, ulceration, and gangrene of the leg (severe limb ischaemia). The investigators state that the extent of the lesion that had been bypassed at surgery and recannalised by angioplasty was similar. However, other critically important angiographic findings were not mentioned. Which were the arterial lesions, stenoses, or occlusions? What were the morphological classifications of the lesions on the basis of TransAtlantic Inter-Society Consensus (TASC)2 definitions? According to a study of percutaneous infrainguinal arterial angioplasty for treatment of chronic limb-threatening ischaemia (rest pain, gangrene, or non-healing ulcers),3 technical failure correlated with TASC D lesions and the presence of occlusion, and major amputation correlated with the combination of arterial occlusion, diabetes, and gangrene. In the BASIL trial, consultant vascular surgeons and interventional radiologists were asked to consider all patients who, on diagnostic imaging, had a pattern of disease which, in their joint opinions, could equally well be treated by either infrainguinal bypass surgery or balloon angioplasty. There were significant differences, however, between surgeons and radiologists with regard to how angiographic variables determined treatment preferences.4 Did the joint opinions of surgeons and radiologists in the BASIL trial consider arterial occlusions or TASC D lesions to be treated equally well by either strategy? Previous studies comparing the clinical effectiveness and costeffectiveness of the two strategies for various degrees of lower limb ischaemia have had limitations5 such as lack of controls; small numbers of patients; poorly defined patients and interventions; inclusion, comparison, and combined analysis of patients with intermittent claudication and www.thelancet.com Vol 367 June 3, 2006
severe limb ischaemia as well as with aortoiliac and infrainguinal disease; retrospective analysis; and short or incomplete follow-up.1 If the abovementioned angiographic findings are not disclosed, the BASIL trial cannot be level 1 evidence any more than the previous studies because of poorly defined arterial lesions. We declare that we have no conflict interest.
*Hisato Takagi, Maiko Furukawa, Takayoshi Kato, Yukihiro Matsuno, Takuya Umemoto [email protected] Department of Cardiovascular Surgery, Shizuoka Medical Centre, 762-1 Nagasawa, Shimizu-cho, Sunto-gun, Shizuoka 411-8611, Japan 1
2
3
4
5
Adam DJ, Beard JD, Cleveland T, et al. Bypass versus angioplasty in severe ischaemia of the leg (BASIL): multicentre, randomised controlled trial. Lancet 2005; 366: 1925–34. Dormandy JA, Rutherford RB. Management of peripheral arterial disease (PAD): TransAtlantic Inter-Society Consensus (TASC). J Vasc Surg 2000; 31: S1–296. Tefera G, Hoch J, Turnipseed WD. Limb-salvage angioplasty in vascular surgery practice. J Vasc Surg 2005; 41: 988–93. Bradbury A, Wilmink T, Lee AJ, et al. Bypass versus angioplasty to treat severe limb ischemia: factors that affect treatment preferences of UK surgeons and interventional radiologists. J Vasc Surg 2004; 39: 1026–32. Bradbury AW. Angioplasty is the first line treatment for critical limb ischaemia: the case against. In: Greenhalgh RM, ed. Vascular and endovascular controversies. London: BIBA Publishing, 2003: 295–307.
Author’s reply Although not the primary objective of the study, the serious shortcomings identified in the pretrial medical management of these highest risk vascular patients were so striking that we felt they deserved specific inclusion and comment in our paper. Numerous studies, including those from our own group, as well as Lloyd Bradley and Stephen Kirker’s own survey, have shown that the medical treatment of patients with peripheral arterial disease (PAD) is much less satisfactory than that generally received by those with coronary artery disease. The reasons for this finding are complex and multifactorial. However, they probably include a less well-developed evidence base with respect to PAD
and, with respect to the UK, cost pressures, the absence of a National Service Framework for PAD, and the lower priority given to PAD in the new general practitioner contracts. The outlook for patients with severe limb ischaemia is extremely poor almost irrespective of what treatment is received. As such, much greater effort should be made and resources expended to identify and treat, predominantly medically, PAD at a much earlier stage so that the progression to severe limb ischaemia can be prevented or at least retarded. Best medical therapy is also likely to improve the safety and durability of surgical and endovascular interventions for severe limb ischaemia once it has developed. I can reassure Hisato Takagi and colleagues that copies of all pretreatment imaging data, which in most cases were intra-arterial digital subtraction angiograms, are being collated centrally and scored independently by two consultant interventional radiologists who are unaware of treatment allocation. As Takagi and colleagues quite rightly point out, these additional data will be important in confirming (as one would expect in a multicentre randomised controlled trial) that the patterns of disease being treated in the two groups of the trial were similar, and in helping to define with more precision which types and patterns of disease are best suited to either balloon angioplasty or bypass surgery. Takagi and colleagues make reference to our earlier work in which we used Delphi consensus methods to showed that, before the BASIL trial, there was little agreement between and among vascular surgeons and interventional radiologists about the relative merits of balloon angioplasty and bypass surgery for severe limb ischaemia secondary to a wide range of different angiographic scenarios. Once all the data from the BASIL trial have been published and digested, we intend to repeat the Delphi studies to 1815