Influence of a rapid change of left ventricular dimensions on the echocardiographic measurement of left ventricular mass by the Penn convention.
OBJECTIVE
The purpose of this study was to test the robustness of the measurement of left ventricle mass (LVM), using Devereux's formula, in the presence of a rapid change in left ventricular volume induced by nitroglycerin.


METHODS
Forty-eight healthy volunteers with excellent echocardiographic recordings were included. The intrapatient variability of LVM measurement was assessed by two consecutive echocardiograms. The intraobserver reproducibility was assessed by the rereading of 19 echocardiograms by the same observer. The effects of nitroglycerin were compared with those of a placebo in a double-blind random manner on, the left ventricular internal dimension in diastole (LVIDd), the interventricular septum thickness, the posterior wall thickness and the LVM.


RESULTS
It was shown that both the intrapatient and the intraobserver reproducibility were high. Nitroglycerin induced a significant decrease in LVIDd compared with placebo (-0.21 +/- 0.24 versus 0.01 +/- 0.21 cm, respectively, P < 0.01) and a non-significant increase in wall thickness. These variations were negatively correlated with each other (r= -0.58, P< 0.01). Despite the change of ventricular dimensions, the variation of LVM induced by nitroglycerin was not significantly different from that induced by placebo (2.0 +/- 16.0 versus 4.7 +/- 17.0 g, respectively, not significant) and close to the intrapatient variability.


CONCLUSIONS
This experiment failed to demonstrate any influence of a rapid variation of ventricle size on the calculation of LVM with the Penn convention and strongly supports the robustness of the method in vivo.
Lantelme
P
P
Service de Cardiologie, Hôpital de la Croix-Rousse, Hospices Civils de Lyon et Faculté de Médecine Lyon-Nord, France.
Bouchayer
D
D
Gayet
C
C
Lievre
M
M
Gessek
J
J
Milon
H
H
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D003971:Diastole / Q000502:physiology; D004311:Double-Blind Method; D004452:Echocardiography / Q000187:drug effects*; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D005996:Nitroglycerin / Q000494:pharmacology; D015588:Observer Variation; D015203:Reproducibility of Results; D013318:Stroke Volume / Q000187:drug effects / Q000502:physiology*; D016277:Ventricular Function, Left / Q000187:drug effects / Q000502:physiology*
D005996:Nitroglycerin