Vascular Medicine and Endovascular Interventions phần 9

. Đặc điểm bệnh nhân khác có liên quan với mức tăng của suy giảm chức năng trong PAD bao gồm một chỉ số khối lượng cơ thể lớn hơn 30 kg/m2, thiếu đi bộ tập thể dục, lịch sử của bệnh phổi, và lịch sử của hẹp ống sống. Tỷ lệ suy giảm chức năng giữa các người có PAD cũng tương tự như | CHAPTER 26 Renal and Mesenteric Arterial Stenosis Renal function at the time of stent placement strongly predicts patency and expected survival after intervention. In patients with normal renal function 3-year survival is 94 74 if serum creatinine is between and mg dL and 52 if serum creatinine is greater than mg dL. The cure rate with angioplasty for renal artery fibro-muscular dysplasia is approximately 25 and some improvement can be expected in approximately 40 Stent placement is now the preferred treatment for most patients with atherosclerotic renal artery disease The technical success rate for renal artery stent placement for atherosclerotic stenosis is 90 The restenosis rate is 15 -20 after renal artery angioplasty and stenting improvement in blood pressure control can be expected in 50 and stabilization or improvement in 60 Imaging the Renal Arteries Conventional angiography is still considered the best anatomic study for evaluating patients with renal artery stenosis. Duplex ultrasonography can be very helpful and should be the first imaging study in patients suspected of having renal artery stenosis. The quality of renal ultrasonography depends on the operator and on other variables such as body habitus but even so the sensitivity of duplex scanning has been reported to be 98 with 98 specificity and high positive and negative predictive values. In many practices computed tomography angiography CTA is now replacing conventional angiography as the anatomic test of choice for evaluating renal arteries. The images are comparable to those of conventional angiography vessels can be evaluated in three dimensions and CTA offers options for clarifying anatomy which may be better than with conventional angiography. Exposure of the patient to radiation from renal CTA is comparable to that from catheter angiography. Magnetic resonance angiography MRA is also a good test to evaluate the anatomy of the renal arteries. It has lower resolution than CTA or .