Background :
@EN Exercise induced ST-segment depression in patients after coronary angioplasty is frequently observed but the mechanism responsible for exercise induced myocardial ischemia early after successful coronary angioplasty is poorly understood. The
object
of this study is to investigate potential determinants of this phenomenon by analizing the clinical, exercise testing, and angiographic characteristics in patients with exercise induced ST-segment depression.
@ES Methods :
@EN The study group comprised 13 patients with exercise induced ST-segment depression(Positive group. M : 12, mean age : 59+/-9year) and 26 patients without exercise induced ST-segment depression(Negative group. M : 22, mean age : 55+/-13 year)
after
succeessful coronary angioplasty in single vessel disease. We compared preangioplasty clinical, angiogrphic, and hemodynamic variables in group with positive and negative results on exercise testing after successful PTCA.
@ES Results :
@EN 1) Clinical characteristics
The initial diagnosis were acute myocardial infarction in 5. Unstable angina in 8 patients at positive group. and 16 and 10 patients at negative group, respectively. there were no significant different in initial diagnosis, risk factor for
coronary
artery disease, and medication used before exercise test at between two groups(Table 1).
2) Cornary angiography and PTCA
The aximal ballooning size were significantly smaller in positive group than negative group (2.7+/-0.5 vs 3.1+/-0.4mm, 2.9+/-0.4mm vs 3.2+/-0.4mm, respectively(p<0.05) but there were no significantly different in ejection fraction. End-diastolic
volume,
end-systolic volume before PTCA. Degree of stenosis of lesion before and after PTCA. Total ballooning time, balloon pressure. Lesion site and infarction relation of lesion at between two groups(Table 2).
3) Exercise test
The mean time from angioplasty to the performance of exercise testing were 9.5+/-4.0days in positive group and 6.1+/-4.5 days in negative group. The mean depression of ST-segent was 1.5+/-0.5mm and was predominantly noted in lateral
leads(V4-6)(9/13 :
69%). There were no significantly different in total exercise time, rate-pressure product, and metabolic cquivalents-exercise time at positive and negative group. But positive results at follow up exercise test were significantly higher in
positive
group(p<0.05) (Table 3).
@ES Conclusions :
@EN There were no difinite determinating factors for exercise induced ST-segment depression early after successful coronary angioplasty by analizing the clinical, angiographic, and exercise testing variables. The pathophysiologic mechanism of
this
finding remain to be elucidated, especially for association of microvascular functional alternation.
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