摘要
Increases of QTc interval dispersion has been reported to be a marker for ischemia. The effects of coronary artery revascularization on QTc dispersion have not been previously reported. We studied QTc in 34 patients with a mean age of 55 years (range 31～72) with coronary artery disease who underwent successful, uncomplicated coronary angioplasty (PTCA). We analysed 12 lead ECG 8 recorded 1 week before. 1 day and 1 week after the PTCA. QT intervals were measured by an observer who was blinded to the time the ECG was recorded, and to all other clinical information. QT intervals were corrected using Bazett's formula. QTc interval dispersion was calculated as the difference between the maximum and minimum of the 12 lead ECG QTc intervals. The QTc dispersion in a day (35±13)ms and a week (34±13)ms after PTCA was significant less reductive than the QTc dispersion (64±16)ms before PTCA (P<0 05). Successful revascularization by PTCA results in a significant reduction in QTc interval dispersion which persists over time. It may be a mechanism of benefit of PTCA therapy. Whether this measurement would predict restenosis in such patients requires further study.
Increases of QTc interval dispersion has been reported to be a marker for ischemia. The effects of coronary artery revascularization on QTc dispersion have not been previously reported. We studied QTc in 34 patients with a mean age of 55 years (range 31～72) with coronary artery disease who underwent successful, uncomplicated coronary angioplasty (PTCA). We analysed 12 lead ECG 8 recorded 1 week before. 1 day and 1 week after the PTCA. QT intervals were measured by an observer who was blinded to the time the ECG was recorded, and to all other clinical information. QT intervals were corrected using Bazett's formula. QTc interval dispersion was calculated as the difference between the maximum and minimum of the 12 lead ECG QTc intervals. The QTc dispersion in a day (35±13)ms and a week (34±13)ms after PTCA was significant less reductive than the QTc dispersion (64±16)ms before PTCA (P<0 05). Successful revascularization by PTCA results in a significant reduction in QTc interval dispersion which persists over time. It may be a mechanism of benefit of PTCA therapy. Whether this measurement would predict restenosis in such patients requires further study.
