The aim of this study was to compare the results of ECG exercise test performed before and after oral administration of nitroglycerine (NTG) in patients with coronary artery disease (CAD), and patients with typical chest pain without any changes in coronary arteriography--syndrome X. We examined 98 patients with typical chest pain, positive result of ECG exercise test, then accordingly to results of coronary arteries assessed with coronary arteriography, patients (pts.) were divided into two groups: group 1--35 pts. without any changes in coronary arteriography--syndrome X, and group 2--48 pts. with significant stenosis present in one or more coronary vessels. Each patient underwent two ECG exercise tests: first without any medication and second performed average 30 minutes after first test, and 5 min after oral administration of 1 table of nitroglycerine. During both tests the following parameters were evaluated: test duration, presence of chest pain, max. ST-T changes, heart rate (HR), and systolic blood pressure (SBP).
Results: In group 1 after NTG time of test duration had shortened from 5.9 +/- 0.4 min to 5.7 +/- 0.6 min. We also observed an increase in max. ST-T complex depression (2.2 +/- 0.5 mm vs 2.4 +/- 0.4 mm) but these differences were not statistically significant. In CAD group, duration of test after NTG was longer (6.2 +/- 1 vs 7.4 +/- 1.2), and normalization of max. ST-T complex depressions (2.7 +/- 0.5 vs 2.0 +/- 0.3 mm) was observed p < 0.01.
Conclusion: Our study suggests that ECG exercise test with NTG may be useful in differentiation of patients with syndrome X and patients with typical coronary artery disease.