T. Miyata

Surgical treatment of Takayasu arteritis

SummaryFrom 1959 to 1991, 93 patients underwent vascular reconstruction for Takayasu arteritis at our institution. The details of the cases were as follows: 16 were of type I (brachiocephalic ischemia), 48 type II (hypertension), 13 type III (extensive lesions with cerebral ischemia and hypertension), and 16 type IV (aneurysms). Carotid reconstruction, repair of atypical aortic coarctation, renovascular reconstruction, and aneurysm repair were performed independently or in combination. Nine operative deaths occurred, 8 cases of which were operated before 1970. The most serious of the delayed complications was suture line aneurysm formation, which was encountered in ten cases. The aneurysms were often found long after the operation, some of them developing even after more than 20 years. Takayasu arteritis is characterized by extensive inflammation and destruction of the medial elastic fibers and long term postoperative observation is mandatory to improve the late survival rate.

Surgical Treatment and Long-term Outcome of Renovascular Hypertension in Children and Adolescents

OBJECTIVES This article describes the long-term outcome of surgical treatment in children with renovascular hypertension (RVH) over a 40-year period. DESIGN Retrospective study. MATERIALS AND METHODS Twenty-five consecutive patients, aged 5-21 years, underwent renal artery (RA) repair from 1967 to 1995. The disease consisted of fibromuscular dysplasia in 17 patients, Takayasus arteritis in 7 and neurofibromatosis type 1 in one patient. RESULTS Twenty-nine RAs were repaired. Primary procedures included aortorenal bypass (ARB) with prosthesis in 10 RAs, autologous vein in five or internal iliac artery in four as conduits, direct reimplantation (DR) in four and nephrectomy in two RAs. Immediate graft failure occurred in three patients despite no peri-operative deaths. After a mean follow-up of 24.4 years, seven patients required secondary nephrectomy. Autologous ARB or DR showed better RA patency and fewer chances for secondary nephrectomy than prosthetic ARB. Hypertension was cured or improved in 21 patients. The overall cumulative survival rate at 20 years was 84%. All five deaths, observed a mean of 12.6 years after the initial operation, were attributed to cardiovascular events. CONCLUSIONS Surgical treatment, especially autologous ARB or DR, seems to provide durable results for paediatric RVH. Long-term observation and control of hypertension is mandatory.

Efficacy of Revascularization for Critical Limb Ischemia in Patients with End-stage Renal Disease

OBJECTIVE To evaluate the outcomes of surgical revascularization for critical limb ischemia in patients with end-stage renal disease (ESRD). PATIENTS AND METHODS From 2004 to 2010, 184 patients with 213 critically ischaemic limbs caused by arteriosclerosis were admitted to The University of Tokyo Hospital. The outcomes of primarily surgical revascularization-based treatments were retrospectively compared in patients with ESRD (ESRD group: 79 patients, 101 limbs) and without ESRD (non-ESRD group: 105 patients, 112 limbs) during the same period. RESULTS Arterial reconstruction was performed on 56 limbs in 46 patients in the ESRD group and 78 limbs in 73 patients in the non-ESRD group (55% vs. 70%; p = .03). Major amputation was performed in 6 of 48 limbs with patent grafts in the ESRD group because of uncontrolled infection or progression of necrosis. The limb salvage rate after arterial reconstruction was significantly lower in the ESRD group than in the non-ESRD group (p = .0019). The postoperative survival rate was lower in the ESRD group than in the non-ESRD group, although this difference was not significant (p = .052). Associated cardiovascular disease and systemic infection were the most frequent causes of death in the ESRD group. There was no significant difference in graft patency between the two groups after distal bypass surgery; however, the limb salvage rate was significantly lower in the ESRD group than in the non-ESRD group (p = .03). CONCLUSIONS Critical limb ischemia associated with ESRD has a poor prognosis. Infection control is particularly important for achievement of good treatment outcomes.

Genome-Wide Association Study of Peripheral Arterial Disease in a Japanese Population.

Characteristics of peripheral arterial disease (PAD) are the occlusion or stenosis of multiple vessel sites caused mainly by atherosclerosis and chronic lower limb ischemia. To identify PAD susceptible loci, we conducted a genome-wide association study (GWAS) with 785 cases and 3,383 controls in a Japanese population using 431,666 single nucleotide polymorphisms (SNP). After staged analyses including a total of 3,164 cases and 20,134 controls, we identified 3 novel PAD susceptibility loci at IPO5/RAP2A, EDNRA and HDAC9 with genome wide significance (combined P = 6.8 x 10−14, 5.3 x 10−9 and 8.8 x 10−8, respectively). Fine-mapping at the IPO5/RAP2A locus revealed that rs9584669 conferred risk of PAD. Luciferase assay showed that the risk allele at this locus reduced expression levels of IPO5. To our knowledge, these are the first genetic risk factors for PAD.