C. Declerck et al., A COMPARISON OF LEFT-VENTRICULAR PERFORMANCE INDEXES MEASURED BY TRANSESOPHAGEAL ECHOCARDIOGRAPHY WITH AUTOMATED BORDER DETECTION, Anesthesiology, 89(2), 1998, pp. 341-349
Background: Automated border detection (ABD) allows semiautomated meas
urement of left ventricular (LV) areas. They can be combined with left
ventricular pressure signals to generate pressure-area loops and pres
sure-dimension indices of contractility. This study compared conventio
nal indices of ventricular performance (fractional area change [FAC] a
nd circumferential fiber shortening [Vcf(c)]) with pressure-dimension
indices of contractility. A secondary aim was to compare the effects o
f volatile anesthetics on the indices. Methods: Using transesophageal
echocardiography with automated border detection, FAC and Vcf(c) were
obtained in 23 patients after cardiopulmonary bypass. Left ventricular
pressures were obtained with a left ventricular catheter. Preload red
uction by inferior vena caval occlusion was used to obtain end-systoli
c elastance (Ees), preload recruitable stroke force (PRSF), and dP/dt(
max.)EDA(-1) (EDA = end-diastolic area). In 11 patients, the measureme
nts were repeated at 1 end-tidal minimum alveolar concentration of hal
othane or isoflurane. The results are expressed as mean +/- SD. Result
s: After cardiopulmonary bypass, FAC was 31.1 +/- 7.9%, Vcf(c) was 0.6
+/- 0.2 circ.s(-1), Ees was 25.8 +/- 11.6 mmHg.cm(-2), PRSF was 60.8
+/- 26.6 mmHg, and dP/dt(max).EDA(-1) was 245 +/- 123.4 mmHg.s(-1) cm(
-2). At 1 minimum alveolar concentration of a volatile anesthetic agen
t, FAG, Vcf(c), and dP/dt(max).EDA(-1) remained unchanged. Significant
decreases in Ees (19%) and PRSF (28%) were observed. Conclusions: The
association between pressure-dimension indices and Vcf(c) or FAC was
weak or nonexistent. A reduction in myocardial contractility induced b
y the administration of volatile anesthetic agents was detected by Ees
and PRSF, but not by FAG, Vcf(c), or dP/dt(max) .EDA(-1). After myoca
rdial revascularization, Ees and PRSF appear more sensitive than FAC o
r Vcf(c) for measuring changes in contractility.