Bogaert J, Gewillig M, Rademakers F, Bosmans H, Verschakelen J, Daenen W, Baert A L
Department of Radiology, University Hospitals, Catholic University of Leuven, Belgium.
J Am Coll Cardiol. 1995 Aug;26(2):521-7. doi: 10.1016/0735-1097(95)80032-c.
This study used magnetic resonance imaging (MRI) to evaluate the morphology and pathophysiology of aneurysm formation after patch angioplasty for coarctation of the aorta.
Late aneurysm formation at the repair site is a well known and frequent complication after patch angioplasty. However, because the underlying mechanisms remain unresolved, postoperative outcome is unpredictable and adequate follow-up difficult.
Seventy-three of 85 patients with patch angioplasty for coarctation of the aorta were screened for aneurysm formation. Magnetic resonance imaging was performed in all 33 patients with an aneurysm, and results were compared with those for 13 control patients and 10 normal subjects. Mean (+/- SD) time between operation and MRI was 12.0 +/- 2.0 years. Aneurysm was defined as the ratio of the diameter of the aorta at the repair site to the diaphragmatic aorta > or = 1.5. Hypoplasia of the transverse arch and recoarctation at the repair site were defined as a ratio < 0.9. Transverse arch ratios on MRI were compared with those on preoperative cineangiography and the pressure gradient between the patient's right and left arm.
All 33 patients with an aneurysm had a hypoplastic transverse arch. The 13 patients with a normal ratio at the repair site had a normal transverse arch ratio (chi square, p < 0.0001). Logarithmic regression showed a significant negative correlation (r = 0.62) between the repair site and transverse arch ratios. A significant pressure difference between the patient's right and left arm was found in patients with versus those without aneurysm (p = 0.0009). No significant difference was found between transverse arch ratios on preoperative cineangiography and postoperative MRI (mean 0.014 +/- 0.1, p = 0.4).
Aneurysm formation at the repair site is highly related to hypoplasia of the transverse arch. Sufficient catch-up growth of a hypoplastic transverse arch is rare after late patch angioplasty. Dynamic phenomena, such as flow acceleration and turbulence, originating in a narrow transverse arch, may contribute to aneurysm formation at the repair site after patch angioplasty.
本研究采用磁共振成像（MRI）评估主动脉缩窄补片血管成形术后动脉瘤形成的形态学及病理生理学特征。
补片血管成形术后修复部位晚期动脉瘤形成是一种众所周知的常见并发症。然而，由于潜在机制尚未明确，术后结果难以预测，且充分的随访也很困难。
对85例行主动脉缩窄补片血管成形术的患者中的73例进行动脉瘤形成筛查。对所有33例患有动脉瘤的患者进行了磁共振成像检查，并将结果与13例对照患者及10例正常受试者的结果进行比较。手术与MRI检查之间的平均（±标准差）时间为12.0±2.0年。动脉瘤定义为修复部位主动脉直径与膈肌水平主动脉直径之比≥1.5。横弓发育不全及修复部位再缩窄定义为该比值＜0.9。将MRI上的横弓比值与术前电影血管造影上的横弓比值以及患者左右臂之间的压力梯度进行比较。
所有33例患有动脉瘤的患者均有横弓发育不全。13例修复部位比值正常的患者横弓比值正常（卡方检验，p＜0.0001）。对数回归显示修复部位与横弓比值之间存在显著负相关（r = 0.62）。有动脉瘤与无动脉瘤患者的左右臂之间存在显著压力差（p = 0.0009）。术前电影血管造影与术后MRI上的横弓比值之间未发现显著差异（平均值0.014±0.1，p = 0.4）。
修复部位动脉瘤形成与横弓发育不全高度相关。晚期补片血管成形术后，发育不全的横弓很少有足够的追赶生长。源于狭窄横弓的血流加速和湍流等动态现象可能导致补片血管成形术后修复部位动脉瘤的形成。
