Rodés-Cabau J, Candell-Riera J, Domingo E, Castell-Conesa J, Anívarro I, Angel J, Aguadé-Bruix S, Padilla F, Soto A, Soler-Soler J
Servei de Cardiologia and Servei de Medicina Nuclear, Hospital General Universitari Vall d'Hebron, Barcelona, Spain.
J Nucl Med. 2001 Dec;42(12):1768-72.
A high number (30%-50%) of reversible defects have been detected early after coronary balloon angioplasty. Inadequate luminal enlargement despite a good angiographic appearance has been suggested as a possible mechanism of these perfusion abnormalities, and some reports have shown better coronary flow reserve after coronary stent implantation than after balloon dilatation. The primary objective of this study was to evaluate the frequency of early ischemic defects detected by maximal exercise (plus dipyridamole) with (99m)Tc-tetrofosmin SPECT after successful coronary angioplasty with stent implantation. A secondary objective was to determine the prognostic value of these early ischemic defects.
Thirty patients without previous myocardial infarction who successfully underwent 1-vessel coronary angioplasty with stent implantation were studied. Maximal-exercise (99m)Tc-tetrofosmin myocardial SPECT, with simultaneous dipyridamole if exercise was suboptimal, was performed at 6 +/- 1 d (mean +/- SD) after percutaneous transluminal coronary angioplasty. At 8 +/- 3 mo, all patients were followed up clinically, and 77% of them underwent follow-up angiography.
The percentage of stenosis decreased from 68.5% +/- 12.6% of luminal diameter to 9.3% +/- 8.8% after stent implantation, and minimal luminal diameter increased from 0.89 +/- 0.36 mm to 2.85 +/- 0.45 mm. Mild-to-moderate reversible myocardial defects in the territory of the dilated artery were detected in 5 patients (17%), with no angiographic or procedural differences occurring between them and patients without ischemic defects. At follow-up, the target lesion revascularization rates depending on the presence or absence of early ischemic defects were 40% and 8%, respectively (P = 0.18). Angiographic restenosis occurred in 3 of 4 patients who had early ischemic defects and underwent follow-up angiography and in 3 of 19 patients who had no early ischemic defects and underwent follow-up angiography (restenosis rate, 75% and 16%, respectively; P < 0.05).
Coronary angioplasty with stent implantation is associated with a 17% rate of ischemic defects early after the procedure. Patients with early myocardial perfusion defects after coronary stent implantation had a high rate of restenosis.
冠状动脉球囊血管成形术后早期检测到大量（30%-50%）可逆性缺损。尽管血管造影表现良好，但管腔扩张不足被认为是这些灌注异常的一种可能机制，并且一些报告显示冠状动脉支架植入术后的冠状动脉血流储备比球囊扩张术后更好。本研究的主要目的是评估成功进行冠状动脉支架植入血管成形术后，通过最大运动（加双嘧达莫）联合（99m）锝-替曲膦单光子发射计算机断层扫描（SPECT）检测到的早期缺血性缺损的发生率。次要目的是确定这些早期缺血性缺损的预后价值。
研究了30例既往无心肌梗死且成功进行单支冠状动脉支架植入血管成形术的患者。在经皮腔内冠状动脉血管成形术后6±1天（平均±标准差）进行最大运动（99m）锝-替曲膦心肌SPECT检查，若运动效果不佳则同时给予双嘧达莫。在8±3个月时，对所有患者进行临床随访，其中77%的患者接受了随访血管造影。
支架植入后管腔狭窄百分比从管腔直径的68.5%±12.6%降至9.3%±8.8%，最小管腔直径从0.89±0.36毫米增加至2.85±0.45毫米。5例患者（17%）在扩张动脉区域检测到轻度至中度可逆性心肌缺损，他们与无缺血性缺损的患者在血管造影或手术方面无差异。随访时，根据是否存在早期缺血性缺损，靶病变血管重建率分别为40%和8%（P = 0.18）。在4例有早期缺血性缺损且接受随访血管造影的患者中有3例发生血管造影再狭窄，在19例无早期缺血性缺损且接受随访血管造影的患者中有3例发生血管造影再狭窄（再狭窄率分别为75%和16%；P < 0.05）。
冠状动脉支架植入血管成形术后早期缺血性缺损发生率为17%。冠状动脉支架植入术后早期心肌灌注缺损的患者再狭窄率较高。
