The Relevance Between Exercise Load Test And Coronary Slow Flow Phenomenon

Objective To investigate The relevance between exercise load test and coronary slow flow phenomenon(CSF).Methods 81 cases of CSF patients with chest pain underwent coronary angiography, without coronary artery obvious stenosis(stenosis of the lumen diameter<40%) were selected as the slow blood flow group. 80 cases with normal coronary angiography and exercise load test electrocardiogram negative were selected as the control group. Maximum corrected QT interval(QTcmax), minimum corrected QT interval(QTcmin), corrected QT dispersion(QTcd) and P-wave dispersion(Pd) were calculated for each case before and after exercise. Record the existence and emerging of fragment QRS complex.Results At rest time, QTcmax in the slow blood flow group was significantly longer than that in the control group(P<0.05), the QTcd of the slow blood flow group increased significantly compared with the control group(P<0.05), but there was no significant difference in QTcmin between the two groups. After exercise, the QTcmax and QTcmin in the slow blood flow group were significantly longer than those in the control group(P<0.05), and QTcd significantly increased compared with the control group(P<0.05). In the slow blood flow group, only 9 cases of exercise load test were positive, accounting for 11.11%. After exercise, the QTcd was significantly decreased compared with rest in the slow blood flow group(46.41±12.21 ms vs 62.81±17.18 ms, P <0.05); Pd was also significantly decreased compared with rest in the slow blood flow group(26.93±8.72 ms vs 39.71±17.26 ms, P<0.05). In the control group, there was no significant change of QTcd and Pd before and after exercise.Conclusion QTd and Pd in CSF patients are higher than that in normal person, and the exercise will make it significantly reduced. More f QRS are detected in patients with CSF. Exercise may improve the blood flow and electrical conductivity of patients with CSF but the data can hardly reach normal.