Chizuko Watanabe

Pathologic implications of restored positive T waves and persistent negative T waves after Q wave myocardial infarction

OBJECTIVES We sought to study the pathologic implications of restored positive T waves and persistent negative T waves in the chronic stage of Q wave myocardial infarction. BACKGROUND Some inverted T waves (coronary T waves) become positive after acute myocardial infarction; others retain their negative T wave component for a long time. The pathologic implications of the difference between restored positive T waves and persistent negative T waves in leads with Q waves has not, until now, been given much careful study. METHODS Of 17 patients with anterior or anteroseptal myocardial infarction confirmed by autopsy, 8 (group P) had positive and 9 (group N) had negative T waves in precordial leads with Q waves > or = 1 year after the onset of myocardial infarction. The appearance and extent of the infarct area and the degree of coronary artery stenosis were evaluated in both groups. RESULTS At autopsy, seven of eight patients in group P had nontransmural fibrotic changes in the anteroseptal or anterior wall. However, seven of nine patients in group N had a transmural myocardial infarction consisting of only a thin fibrotic layer in the anteroseptal or anterior wall. The left anterior descending coronary artery showed 75% stenosis in 1 patient in each group but > 90% stenosis in the remaining 15 patients. CONCLUSIONS Persistent negative T waves in leads with Q waves in the chronic stage of myocardial infarction indicate the presence of a transmural infarction with a thin fibrotic layer, whereas positive T waves indicate a nontransmural infarct containing viable myocardium within the layer.

A morphological study of the normally aging heart

A morphological examination of aging was performed on 141 normal hearts selected from a total of 972 consecutive autopsies on persons aged 60 years or over. The average heart weight was 270 ± 41 g. The circumference of the valvular ring was 99 ± 10 mm in the tricuspid valve, 68 ± 8 mm in the pulmonic valve, 83 ± 10 mm in the mitral valve, and 73 ± 7 mm in the aortic valve. The thickness of the tricuspid valve (anterior leaflet) was 0.9 ± 0.3 mm, pulmonic (anterior cusp) 0.4 ± 0.3 mm, mitral (anterior leaflet) 1.3 ± 0.6 mm, and aortic (posterior cusp) 1.0 ± 0.6 mm. Cardiac chamber volumes were as follows: 40 ± 14 mL in the right atrium, 22 ± 7 mL in the right ventricle, 37 ± 12 mL in the left atrium, and 7.3 ± 3.4 mL in the left ventricle. The circumference of the tricuspid ring was the largest. Left-sided valves were thicker than right-sides valves, and atrioventricular valves were thicker than semilunar valves. Cardiac chamber volumes were generally larger on the right side. Because this study was limited to hearts from persons aged 60 years or over, age-related changes were observed in only four parameters: (i) the circumference of the aortic valvular ring, (ii) the thickness of the aortic posterior cusp, (iii) the thickness of the pulmonic anterior cusp, and (iv) the volume of the left ventricle. With increasing age the aortic valvular ring dilated, the aortic posterior cusp and the pulmonic anterior cusp thickened, and the left ventricular volume diminished.A morphological examination of aging was performed on 141 normal hearts selected from a total of 972 consecutive autopsies on persons aged 60 years or over. The average heart weight was 270 ± 41 g. The circumference of the valvular ring was 99 ± 10 mm in the tricuspid valve, 68 ± 8 mm in the pulmonic valve, 83 ± 10 mm in the mitral valve, and 73 ± 7 mm in the aortic valve. The thickness of the tricuspid valve (anterior leaflet) was 0.9 ± 0.3 mm, pulmonic (anterior cusp) 0.4 ± 0.3 mm, mitral (anterior leaflet) 1.3 ± 0.6 mm, and aortic (posterior cusp) 1.0 ± 0.6 mm. Cardiac chamber volumes were as follows: 40 ± 14 mL in the right atrium, 22 ± 7 mL in the right ventricle, 37 ± 12 mL in the left atrium, and 7.3 ± 3.4 mL in the left ventricle. The circumference of the tricuspid ring was the largest. Left-sided valves were thicker than right-sides valves, and atrioventricular valves were thicker than semilunar valves. Cardiac chamber volumes were generally larger on the right side. Because this study was limited to hearts from persons aged 60 years or over, age-related changes were observed in only four parameters: (i) the circumference of the aortic valvular ring, (ii) the thickness of the aortic posterior cusp, (iii) the thickness of the pulmonic anterior cusp, and (iv) the volume of the left ventricle. With increasing age the aortic valvular ring dilated, the aortic posterior cusp and the pulmonic anterior cusp thickened, and the left ventricular volume diminished.