Author + information
- Received November 12, 1990
- Revision received January 23, 1991
- Accepted February 18, 1991
- Published online July 1, 1991.
- Juan Carlos Kaski, MD, FACC*,1,
- Dimitris Tousoulis, MD1,
- Alfredo R. Galassi, MD1,
- Eugene McFadden, MRCP1,
- Wagner I. Pereira, MD1,
- Filippo Crea, MD, FACC1 and
- Attilio Maseri, FRCP, FACC1
- ↵*Address for reprints: Juan Carlos Kaski, MD, Cardiovascular Research Unit, Hammersmith Hospital, Ducane Road, London W12 ONN, England.
The vasomotor response of proximal and distal angiographically normal coronary artery segments was studied in 12 patients with syndrome X, 17 age- and gender-matched patients with chronic stable angina and 10 control subjects with atypical chest pain and a normal coronary arteriogram. Ergonovine (300 fig by intravenous injection) and isosorbide dinitrate (1 mg by intracoronary injection) were administered to all patients. Computerized coronary artery diameter measurement (angiographically normal segments only) was carried out before and after the administration of ergonovine and nitrate.
Baseline intraluminal diameters (mean ± SEM) of proximal and distal coronary segments were not significantly different in control subjects and patients with syndrome X or coronary artery disease (proximal 2.88 ± 0.19,3.01 ± 0.13 and 2.86 ± 0.13 mm; distal 1.57 ± 0.09,1.70 ± 0.10 and 1.61 ± 0.06 mm, respectively). With ergonovine, proximal segments constricted by 10 ± 2%, 7 ± 2% and 11 ± 3% and distal segments by 12 ± 3%, 14 ± 3% and 14 ± 2% in control subjects and patients with syndrome X or coronary artery disease, respectively (p = NS). With isosorbide dinitrate, proximal coronary segments dilated by 11 ± 2%, 10 ± 2% and 8 ± 2% (p = NS) and distal segments by 15 ± 2%, 11 ± 3% and 13 ± 2% (p = NS) in control subjects and patients with syndrome X or coronary artery disease, respectively. Within groups, constriction in response to ergonovine and dilation in response to nitrate were not significantly different in proximal and distal segments.
The results of this study indicate that coronary diameters and the vasomotor response to ergonovine and isosorbide dinitrate of angiographically normal coronary artery segments at rest are not significantly different in patients with noncardiac chest pain, syndrome X or coronary artery disease. Although coronary flow reserve is impaired in patients with syndrome X, reactivity of large epicardial vessels to nitrate and ergonovine is within the physiologic range in these patients.
- Received November 12, 1990.
- Revision received January 23, 1991.
- Accepted February 18, 1991.
- American College of Cardiology Foundation