Objectives: The spectrum of patients with 'angina and normal coronary arteries' ranges from severe vasospasm to atypical chest pain. Among those with typical angina, however, little is known about similarities in the clinical profile and circadian presentation between typical nonvasospastic angina and normal coronary arteries (tANCA) and vasospastic angina (VA).
Materials and methods: Clinical, ECG, and angiographic features as well as the circadian characteristics of angina were compared between 384 tANCA and 273 VA patients. Follow-up events were also analyzed.
Results: tANCA patients had greater female predominance (61 vs. 18%), higher incidence of dyspnea to moderate exertion (49 vs. 12%), lower incidence of tobacco smoking (25 vs. 67%), but a similar low rate of diabetes (8.9 vs. 4.4%). In both groups, however, dyspnea and smoking were associated with female and male sex, respectively. tANCA patients showed lower but non-negligible frequency of early morning (25 vs. 67%) and evening angina (37 vs. 54%), similar rate of nocturnal angina (47 vs. 50%), and higher rate of emotional angina (49 vs. 31%). Moreover, a high proportion of patients gained pain relief with nitroglycerin (97% in VA, 246/253, and 76% in tANCA, 231/306). At 140 months, frequent angina (>10 episodes/year) was rare (VA: 7.1% vs. tANCA: 6.3%) as was the rate of cardiac death/myocardial infarction (7.3 vs. 6.0%, P=0.524).
Conclusion: Despite differences in the clinical profile between VA and tANCA patients, there is notable sharing of circadian presentation of rest angina, response to nitroglycerin, and long-term presence and frequency of angina that suggests more similarities in underlying mechanisms than heretofore suspected.