Association of Increased Myocardial Contractility and Elevated End-Diastolic Wall Tension With Short-Term Myocardial Ischemia: A Pressure-Volume Analysis

3D Real-Time Echocardiography Combined with Mini Pressure Wire Generate Reliable Pressure-Volume Loops in Small Hearts

“…Using higher doses of phenylephrine (10 μg/kg/min) than Cassidy et al (2 μg/kg/min) [ 30 ], we observed a significant increase in Ees. The few studies that have evaluated ventricular performance under the influence of esmolol in piglets showed a significant decrease in Ees [ 24 , 25 ] and our results confirm these data. Application of esmolol after adrenergic stimulation resulted in a decrease in ESP, dp/dt max , dp/dt min , Ees and EF as well as an increase in ESV, EDV and EDP [ 25 ].…”

“…Baseline measurements of PVL 3D and PVL Cond were performed under closed and open chest conditions. As poor 3DE image quality on a closed chest results in inappropriate volume calculations [ 24 ], distal partial sternotomy was performed to expose an appropriate apical ventricular area after baseline measurements had been taken ( Fig 2 ). Once the baseline measurements had been repeated on the open chest, hemodynamic conditions were modified by increasing the afterload (alpha-adrenergic stimulation with phenylephrine: bolus 10 μg/kg followed by 10 μg/kg/min continuous infusion (Baxter, Deerfield, Il, USA)).…”

“…Once the baseline measurements had been repeated on the open chest, hemodynamic conditions were modified by increasing the afterload (alpha-adrenergic stimulation with phenylephrine: bolus 10 μg/kg followed by 10 μg/kg/min continuous infusion (Baxter, Deerfield, Il, USA)). After a washout period of 20 minutes, beta-adrenoceptor blockage was started (esmolol 1mg/kg repeatedly (Baxter, Unterschleißheim, Germany)) using the decrease of dp/dt max and P max of more than 20% as indicators for effectiveness of esmolol dose [ 24 , 25 ]. During each hemodynamic state PVL 3D and PVL Cond were obtained successively.…”