[Variations of left ventricular-arterial coupling in septic shock].

Objective To explore the variations of left ventricular-arterial coupling and elucidate its mechanisms in septic shock. Methods Septic shock rabbits were established by an intravenous injection of endotoxin.A total of 12 rabbits were divided randomly into sham operation group (S,n=6) and endotoxin injection group (E, n=6).Ultrasonic echocardiography and hemodynamic monitoring were conducted at 0 h (30-min post-operation), 2 h (1-hour after endotoxin or saline injection) and 4 h (3-hour after endotoxin or saline injection) and the relative hemodynamic indices were recorded. Results (1) In E group, end-systolic elastance (Ees) at 2 h was lower than that at 0 h (75.72±5.16 vs 90.77±7.17 mm Hg/ml) and Ees at 4 h was lower than that at 2 h (58.45±3.63 vs 75.72±5.16 mm Hg/ml,P<0.05). (2) In E group, left ventricular diastolic volume (LVDV) at 2 h and 4 h were both lower than that at 0 h (3.26±0.21 vs 3.58±0.25 ml, 3.27±0.19 vs 3.58±0.25 ml).And left ventricular end diastolic compliance (Ced) at 4 h were lower than that at 0 h and 2 h (0.61±0.05 vs 0.74±0.07 ml/mm Hg, 0.61±0.05 vs 0.75±0.08 ml/mm Hg, P<0.05). (3) In E group, Ea at 2 h and 4 h was lower than that at 0 h (41.35±2.87 vs 50.46±3.22 mm Hg/ml, 40.13±2.68 vs 50.46±3.22 mm Hg/ml,P<0.05). (4) In E group, Ea/Ees at 4 h was higher than that at 0 h and 4 h (0.70±0.07 vs 0.57±0.06,0.70±0.07 vs 0.56±0.05,P<0.05).And Ea/Ees at 2 h had no significant difference with that at 0 h (0.56±0.05 vs 0.57±0.06, P<0.05). Conclusion During compensatory stage of septic shock, left ventricular-arterial coupling shows no significant variation.However, during decompensatory stage of septic shock, there is significant left ventricular-arterial decoupling.The main reason for decoupling lies in that the decrease of left myocardial contractility is more significant than that of left ventricular afterload.And ventricular diastolic dysfunction may also participate. Key words: Shock,septic; Shock; Infection; Ventricular-arterialcoupling