Myocardial hypertrophy, rate of change of free wall thickness and directional components of ventricular power in man.
The diastolic (Vd) and systolic volumes, the average free wall diastolic thickness (hd) and left cardiac cavity pressures were determined in 25 subjects using monoplan angiography. Ten subjects presented a normal angiogram (NA), 5 a myocardiopathy with predominant dilatation (MCD), 4 a myocardiopathy with predominant non obstructive hypertrophy (MCH), and 6 a volume overload (VO). All the subjects had a normal coronary-cineangiogram. Myocardial volume (Vw) and systolic thickness were calculated from hd and from end-diastolic and end-systolic internal dimensions. The degree of myocardial hypertrophy was estimated from the value of Vw/Vd. The directional components of the total systolic elemental power due to thickening (average radial power : Pr) and to midwall circumferential shortening (average equatorial power : Pe) were calculated for each subject. Patients with NA, with MCD and with VO presented a positive linear correlation between Pr/Pe and Vw/Vd (r = 0.90). Patients with MCH were clearly below the regression line defined by the other groups. This relationship suggests that the contribution to the total power due to the thickening component is greater with increasing cardiac hypertrophy, except in the case of subjects showing an "inappropriate" hypertrophy.
D000328:Adult; D000792:Angiography; D001696:Biomechanical Phenomena; D006332:Cardiomegaly / Q000503:physiopathology*; D003971:Diastole; D005260:Female; D006352:Heart Ventricles / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013599:Systole