Decreased QTc dispersion after coronary revascularization: relationships with the quantitative degree of improvement in myocardial ischemia

Object and Methods: : : :Thirty-four patients (mean age:58.1±8.3 years, M:F=21:13 with angina in the absence of previous myocardial infarction, who underwent percutaneous coronary intervention (stenting and/or balloon PTCA, n=25 or coronary arterial bypass grafting (CABG, n=9 were evaluated to assess the relations- hips between the degree of improvement in myocardial dipyridamole Tl-201 SPECT and the degree of decrease in QTc dispersion after coronary revascularization. QTc dispersions were measured manually using digitizer by a single observer from ECGs printed at 25 mm/sec, 1 day before, immediately, 1 day, and 1 month after the revasc- ularization procedure. Myocardial Tl-201 SPECTs were performed before and 1 month after the revascularization and ischemic indices were measured in all cases. Results:Mean QTc dispersion was 51.4±17.0 msec before revascularization, 42.6±15.1 msec immediately after, 45.6±19.3 msec 1 day after and 37.4±11.6 msec 1 month after revascularization. The decrease of QTc dispersion immediate (p=0.001 and 1 month (p<0.001 after revascularization, were statistically significant. Mean Tl-201 SPECT ischemic index measured before the revascularization (7.8±5.9 was significantly higher (p<0.001 than the one measured 1 month after the revascu- larization (1.5±2.8. But, in Δischemic index (ischemic index before revascularization-ischemic index 1 month afer revascularization, there was no significant difference between the patients with decrease in QTc dispersion after revascularization (6.2±6.3, n=27 and the patients without decrease in QTc dispersion (6.6±5.2, n=7). There was no statistically significant correlation between Δ QTc (QTc dispersion before revascularization- QTc dispersion 1 month afer revascularization and Δischemic index in total subjects. Conclusion:QTc dispersions decrease after successful coronary revascularizations in patients with angina, but considering the relationships between the changes of QTc dispersions and ischemic indices in myocardial dipyridamole Tl-201 SPECT, the degree of decrease in QTc dispersion after coronary revascularization does not have the relationships with the quantitative degree of improvement in myocardial ischemia. (Korean Circulation J 2000;30(8 :998-1003

[1]  Seung‐Jung Park,et al.  Dipyridamole Tl-201 SPECT in Hypertrophic Cardiomyopathy with Asymmetric Septal Hypertrophy:Characteristics of Perfusion Abnormality and Correlation with Clinical Parameters , 1999 .

[2]  T. Ashikaga,et al.  Increased QTc dispersion predicts lethal ventricular arrhythmias complicating coronary angioplasty. , 1998, The American journal of cardiology.

[3]  Seung‐Jung Park,et al.  Change of QT Dispersion Following PTCA in Angina Patients , 1998 .

[4]  T. Kakuta,et al.  Increased QT dispersion in patients with vasospastic angina. , 1998, Circulation.

[5]  B. Kim,et al.  Effect of Coronary Angioplasty on QT and JT Dispersion , 1998 .

[6]  J. Potratz,et al.  Relation between QT dispersion and the extent of myocardial ischemia in patients with three-vessel coronary artery disease. , 1998, The American journal of cardiology.

[7]  J. Molnar,et al.  Effect of intracoronary balloon inflation at percutaneous transluminal coronary angioplasty on QT dispersion. , 1998, American heart journal.

[8]  A. Hofman,et al.  QTc dispersion predicts cardiac mortality in the elderly: the Rotterdam Study. , 1998, Circulation.

[9]  U. Sechtem,et al.  QT dispersion is determined by the extent of viable myocardium in patients with chronic Q-wave myocardial infarction. , 1997, Circulation.

[10]  R. F. Kelly,et al.  Effect of coronary angioplasty on QT dispersion. , 1997, American heart journal.

[11]  H. Youn,et al.  Change of QT Dispersion Following Successful Percutaneous Transluminal Coronary Angioplasty(PTCA) , 1997 .

[12]  D. Wyse,et al.  Effect of coronary angioplasty on precordial QT dispersion. , 1997, The American journal of cardiology.

[13]  H. Bazett,et al.  AN ANALYSIS OF THE TIME‐RELATIONS OF ELECTROCARDIOGRAMS. , 1997 .

[14]  P. Sutton,et al.  Acute ischaemia: a dynamic influence on QT dispersion , 1997, The Lancet.

[15]  A. Michelucci,et al.  Effects of Ischemia and Reperfusion on QT Dispersion During Coronary Angioplasty , 1996, Pacing and clinical electrophysiology : PACE.

[16]  Steinberg Js,et al.  QT Dispersion: Current and Future Clinical Role. , 1996 .

[17]  H. Seo,et al.  Diagnostic Value of QT and JT Dispersion in Exercise ECG , 1995 .

[18]  D. D. Bono,et al.  QT dispersion and mortality after myocardial infarction , 1995, The Lancet.

[19]  P. Sager,et al.  Effects of amiodarone, sematilide, and sotalol on QT dispersion. , 1994, The American journal of cardiology.

[20]  D E Ward,et al.  QT Dispersion: Problems of Methodology and Clinical Significance , 1994, Journal of cardiovascular electrophysiology.

[21]  Jeffrey L. Anderson,et al.  Reduction in QT Interval Dispersion by Successful Thrombolytic Therapy in Acute Myocardial Infarction , 1994, Circulation.

[22]  S. Cobbe,et al.  QT interval dispersion: a non-invasive marker of susceptibility to arrhythmia in patients with sustained ventricular arrhythmias? , 1994, British heart journal.

[23]  P. Davey,et al.  QT interval dispersion in chronic heart failure and left ventricular hypertrophy: relation to autonomic nervous system and Holter tape abnormalities. , 1994, British heart journal.

[24]  C. Lang,et al.  QT dispersion and sudden unexpected death in chronic heart failure , 1994, The Lancet.

[25]  A Nava,et al.  Comparison of QT dispersion in hypertrophic cardiomyopathy between patients with and without ventricular arrhythmias and sudden death. , 1993, The American journal of cardiology.

[26]  J. Fothergill,et al.  Automated measurement of QT interval dispersion from hard-copy ECGs. , 1993, Journal of electrocardiology.

[27]  S. Cobbe,et al.  Effects of the class III antiarrhythmic drug dofetilide on ventricular monophasic action potential duration and QT interval dispersion in stable angina pectoris. , 1992, The American journal of cardiology.

[28]  D. Wyse,et al.  Precordial QT Interval Dispersion as a Marker of Torsade de Pointes: Disparate Effects of Class Ta Antiarrhythmic Drugs and Amiodarone , 1992, Circulation.

[29]  P. Nihoyannopoulos,et al.  QT‐interval abnormalities in hypertrophic cardiomyopathy , 1992, Clinical cardiology.

[30]  J. Mccomb,et al.  QT dispersion: an indication of arrhythmia risk in patients with long QT intervals. , 1990, British heart journal.

[31]  H. Figulla,et al.  Occurrence and clinical significance of endocardial late potentials and fractionations in idiopathic dilated cardiomyopathy. , 1988, British heart journal.

[32]  D. Mirvis,et al.  Spatial variation of QT intervals in normal persons and patients with acute myocardial infarction. , 1985, Journal of the American College of Cardiology.

[33]  Vloka,et al.  QT Dispersion: Current and Future Clinical Role. , 1996, The Journal of invasive cardiology.