心脏移植患者对去氧肾上腺素的冠状动脉血管运动反应。

Aptecar Eduardo, Le Corvoisier Philippe, Teiger Emmanuel, Dupouy Patrick, Vermes Emmanuelle, Sediame Said, Hittinger Luc, Loisance Daniel, Dubois-Rande Jean-Luc, Montagne Olivier

Fédération de Cardiologie, Institut National de la Santé et de la Recherche Médicale U400, Centre d'Investigation Clinique, Hôpital Henri Mondor, Assistance Publique-Hôpitaux de Paris, Université Paris XII, Créteil, France.

J Heart Lung Transplant. 2006 Aug;25(8):912-20. doi: 10.1016/j.healun.2006.03.001. Epub 2006 Jul 10.

BACKGROUND

Coronary vasomotor responses to sympathetic stimulation vary with endothelial-layer integrity or presence of atherosclerosis. Our study objective was to assess the effects of phenylephrine-induced alpha-adrenergic stimulation on coronary vasomotion in heart transplant recipients with and without graft atherosclerosis.

METHODS

Intracoronary phenylephrine (alpha(1)-selective agonist) was injected in 6 control subjects, 9 recipients with angiographically normal coronary arteries and 8 recipients with mild or moderate atherosclerosis. Coronary flow velocity was measured using a Doppler guide-wire. The diameters of 3 epicardial segments of the left coronary artery and coronary blood flow and resistance were assessed at baseline, after infusion of increasing acetylcholine doses (10(-7) and 10(-6) mol/liter) and after phenylephrine (150- to 200-microg bolus). Systemic and coronary hemodynamic parameters were measured immediately after acetylcholine and 1, 3, 5, 7, 10 and 15 minutes after phenylephrine.

RESULTS

Phenylephrine induced similar significant increases in rate pressure product in the 3 groups. Acetylcholine induced epicardial vasodilation in controls and vasoconstriction in transplant recipients. Phenylephrine induced epicardial vasodilation in controls and in angiographically normal recipients; subsequent vasoconstriction occurred in this last group. In the recipients with angiographic abnormalities, sustained vasoconstriction occurred. At peak phenylephrine effect, coronary blood flow (CBF) increased significantly (p < 0.001 vs baseline) in all 3 groups. Coronary resistance decreased in the 3 groups but the decrease was smaller in the recipients with angiographic abnormalities (p < 0.05 vs controls).

CONCLUSIONS

In heart transplant patients, graft atherosclerosis unmasks the direct coronary vasoconstricting effects of pharmacologic alpha-adrenergic stimulation.

背景

冠状动脉对交感神经刺激的血管舒缩反应因内皮细胞层完整性或动脉粥样硬化的存在而有所不同。我们的研究目的是评估去氧肾上腺素诱导的α-肾上腺素能刺激对有或无移植血管动脉粥样硬化的心脏移植受者冠状动脉血管运动的影响。

方法

向6名对照受试者、9名冠状动脉造影正常的受者和8名有轻度或中度动脉粥样硬化的受者冠状动脉内注射去氧肾上腺素（α1选择性激动剂）。使用多普勒导丝测量冠状动脉血流速度。在基线、输注递增剂量的乙酰胆碱（10-7和10-6摩尔/升）后以及注射去氧肾上腺素（150至200微克推注）后，评估左冠状动脉3个心外膜节段的直径、冠状动脉血流量和阻力。在注射乙酰胆碱后立即以及注射去氧肾上腺素后1、3、5、7、10和15分钟测量全身和冠状动脉血流动力学参数。

结果

去氧肾上腺素在3组中均引起相似的显著心率血压乘积增加。乙酰胆碱在对照组中引起心外膜血管舒张，而在移植受者中引起血管收缩。去氧肾上腺素在对照组和冠状动脉造影正常的受者中引起心外膜血管舒张；在最后一组中随后出现血管收缩。在有血管造影异常的受者中，出现持续血管收缩。在去氧肾上腺素作用峰值时，所有3组的冠状动脉血流量（CBF）均显著增加（与基线相比，p<0.001）。3组的冠状动脉阻力均降低，但有血管造影异常的受者降低幅度较小（与对照组相比，p<0.05）。