Evaluation of coronary flow reserve in patients with vasospastic angina

摘要

OBJECTIVES: The presence of microvascluar impairment was evaluated in 154 patients with vasospastic angina identified by the acetylcholine provocation test. METHODS: Coronary flow reserve was evaluated with a Doppler flow guidewire in 128 vessels of 72 patients with chest pain, but no significant coronary stenosis(less than 50% stenosis) and no clinical factors that affect coronary flow reserve. Coronary flow reserve was obtained from the ratio of adenosine triphosphate-induced maximum/baseline averaged peak velocity. These vessels were classified into 2 categories according to whether acetylcholine-induced vasospasm was positive or negative. Vasospasm positive was defined as more than 90% stenosis provoked with chest pain and/or ischemic ST change. Positive vessels were subdivided according to focal or diffuse vasospasm. These vessels were also classified into 2 other categories according to whether vasospasm in the distal artery was positive or negative. RESULTS: Coronary flow reserve was significantly lower in vessels with vasospasm than in vessels without vasospasm in patients without vasospasm(2.9 +/- 0.8 vs 3.6 +/- 1.0, p = 0.0005). Coronary flow reserve was significantly lower in vessels without vasospasm in patients with vasospasm than in vessels without vasospasm in patients without vasospasm(3.0 +/- 0.8 vs 3.6 +/- 1.0, p = 0.03). There was no significant difference in coronary flow reserve between vessels with vasospasm and vessels without vasospasm in patients with vasospasm(2.9 +/- 0.8 vs 3.0 +/- 0.8, p = 0.8). There was no significant difference in coronary flow reserve between focal and diffuse vasospasm(3.2 +/- 0.8 vs 2.9 +/- 0.8, p = 0.3). Coronary flow reserve was significantly lower in vessels with vasospasm in the distal artery than in vessels without vasospasm in the distal artery (2.8 +/- 0.8 vs 3.4 +/- 1.0, p = 0.004). CONCLUSIONS: Patients with vasospastic angina have microvascular impairment in both vessels with vasospasm, and vessels without vasospasm. Microvascular impairment is prominent in vessels with vasospasm in the distal artery.