Related Experiment Videos
New diagnostic evidence on the T wave map indicating involved coronary artery in patients with angina pectoris
T Ishikawa1, S Watabe, Y Yamada
1First Department of Internal Medicine, School of Medicine, Nagoya University, Japan.
Insights
T wave map changes can identify coronary artery disease in patients with angina. These body surface potential maps offer insights beyond routine electrocardiography, aiding in diagnosis and localization of ischemic areas.
Area of Science:
- Cardiology
- Medical Imaging
- Diagnostic Electrocardiology
Background:
- Angina at rest signifies potential coronary artery disease.
- Routine electrocardiography (ECG) may not fully capture T wave abnormalities in angina.
- Body surface potential mapping (BSPM) offers a more detailed analysis of cardiac electrical activity.
Purpose of the Study:
- To determine the clinical significance of T wave map changes in patients experiencing angina at rest.
- To correlate specific T wave map patterns with coronary artery stenosis.
- To assess the diagnostic value of BSPM for identifying the affected coronary artery.
Main Methods:
- Obtained body surface isopotential T wave distributions in 48 patients with documented single-vessel disease and compared them to healthy subjects and patients with left ventricular overload.
- Classified T wave map abnormalities into three types (I, II, III) based on the location and characteristics of negative potentials.
- Correlated map findings with angiographically determined coronary artery lesions (LAD, RCA, LCx).
Main Results:
- Fifty percent (24/48) of angina patients exhibited T wave map abnormalities.
- Type I abnormalities correlated with left anterior descending artery (LAD) stenosis.
- Type II and III abnormalities correlated with right coronary artery (RCA) or left circumflex artery (LCx) disease, respectively.
- Abnormalities differed significantly from those seen in left ventricular overload.
- Successful percutaneous transluminal coronary angioplasty (PTCA) led to normalization of Type I T wave map changes in LAD lesions.
Conclusions:
- T wave map abnormalities are clinically significant in patients with angina at rest.
- Specific T wave map patterns can indicate the location of coronary artery stenosis (LAD, RCA, or LCx).
- BSPM provides diagnostic information regarding the involved coronary artery and ischemic area, surpassing routine ECG capabilities.
Abstract:
To define the clinical significance of T wave map changes in patients with angina at rest, body surface isopotential T distributions were obtained in 48 patients with single-vessel disease (left anterior descending artery, 34; right coronary artery, eight; left circumflex artery, six) documented angiographically and were compared with those in 120 healthy subjects and those in 19 patients with left ventricular overload whose electrocardiograms showed negative T waves accompanied by an increase in R wave amplitude in left precordial leads. The T wave map abnormalities were observed in 24 of 48 patients (50%) with angina and were classified into three types: (1) type I (18 patients, 37.5%) was characterized by a segmental negative potential in the positive area located at the left thorax and the minimum at the peak of T wave positioned in the upper portion of the left anterior chest, (2) type II (three patients, 6.3%) was characterized by a negative potential with a minimum in the inferior thorax and an indentation of negative potential at the lower margin of the positive potential located over the upper thorax, and (3) type III (three patients, 6.3%) was characterized by a negative potential with a minimum at the back throughout the period of T wave. All patients showing T wave map abnormalities of type I had a significant stenosis of the left anterior descending artery. Likewise, all patients with type II or III had single-vessel disease of the right coronary or left circumflex artery, respectively. All types of T wave map changes observed in patients with angina were different from those in patients with left ventricular overload, whose maps showed the generalized negative potential at the inferior thorax and the left back and the minima clustered at the precordium. In seven patients with lesions of the left anterior descending artery, T wave map abnormalities of type I recovered to normal after successful percutaneous transluminal coronary angioplasty. The behavior of the negative potential and its extrema on the T wave map, which was not available from routine electrocardiography, was indicative of the involved coronary artery and probably of its associated ischemic area in one-half of our patients with angina pectoris.