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Objective: To evaluate the effects of 2 different administration modalities of levosimendan (start before cardiopulmonary bypass [CPB] and at the end of CPB) compared with a standard treatment with milrinone started at the end of CPB in cardiac surgery patients with a preoperative ejection fraction <30%., Design: A prospective study., Setting: A university hospital., Participants: Sixty patients undergoing elective cardiac surgery with CPB., Interventions: Patients were randomly assigned to 3 different treatment options for weaning from CPB after cardiac surgery. Group A received milrinone, 0.5 microg/kg/min, after the release of the aortic cross-clamp; group B received levosimendan, 0.1 microg/kg/min, after the induction of anesthesia; and in group C, levosimendan, 0.1 microg/kg/min, was started immediately after the release of the aortic cross-clamp. In all patients, additional dobutamine, 5 microg/kg/min, was initiated after the release of the aortic cross-clamp. Norepinephrine maintained mean arterial pressure constant., Measurements and Main Results: Stroke volume after surgery was initially higher than at baseline in all groups and highest in group B. Stroke volume declined 12 hours after surgery in group A but not in groups B and C (p < 0.05 between groups), despite similar filling pressures. Four patients in group A, none in group B, and 1 in group C died within 30 days of surgery. Postoperative atrial fibrillation was observed in 10 patients in group A, 7 patients in group C, and only 1 in group B (p < 0.01). No differences were observed in postoperative troponin I release among groups., Conclusion: In the conditions of the present study, starting the levosimendan treatment before CPB was associated with a higher initial postoperative stroke volume and a lower incidence of postoperative atrial fibrillation, but had no effect on the extent of postoperative troponin I release.

Objective: To compare an arterial pressure-derived cardiac output (APCO) (Vigileo software version 1.07; Edwards Lifesciences, Irvine, CA) and a thermodilution cardiac output (CCO) as methods for measuring cardiac output under different pathologic and experimental conditions that induce changes in arterial waveform morphology., Design: A prospective study., Setting: A university hospital, single institutional., Participants: Fifty-two patients undergoing elective cardiac surgery., Interventions: Simultaneous APCO and CCO were compared in low-risk patients undergoing elective coronary artery surgery (without valvular disease) (control, n = 20), patients with aortic stenosis (AS, n = 10), aortic insufficiency (AI, n = 10), and intra-aortic balloon pump (IABP, n = 12). In the control group, additional data were registered before and after median sternotomy and phenylephrine administration., Measurements and Main Results: In the control group, Bland-Altman showed a bias of -3% (95% limits of agreement: -59% to +53%) before cardiopulmonary bypass (CPB) and of -1% (95% limits of agreement: -51% to +50%) after CPB. In the AS group, the bias was -5% (95% limits of agreement: -34% to +24%) before CPB and 1% (95% limits of agreement: -28 to +30%) after CPB. In the AI group bias was +32% (95% limits of agreement: -4% to +68%) before CPB and -2% (95% limits of agreement: -35% to +32%) after CPB. Median sternotomy decreased CCO by 10% +/- 10%, whereas it increased APCO by 56% +/- 28%. Phenylephrine administration decreased CCO by 11% +/- 16%, whereas it increased APCO by 55% +/- 34%., Conclusions: Cardiac output measurement based on uncalibrated pulse contour analysis is able to reflect cardiac output measured with the continuous thermodilution method in patients undergoing uncomplicated coronary artery surgery. However, in situations in which the arterial pressure waveform is changed, agreement between techniques may be altered and data obtained with uncalibrated pulse contour analysis may become less reliable.

Objective: The purpose of this study was to determine whether a relationship exists between the inferior vena cava diameter (IVCD) or the superior vena cava diameter (SVCD) measured at the point of entry into the right atrium using transesophageal echocardiography (TEE) and the central venous pressure (CVP) under different experimental conditions., Design: Prospective study., Setting: University hospital, single institution., Participants: Seventy patients undergoing elective cardiac surgery., Interventions: CVP, IVCD, and SVCD were measured in a 2-dimensional, long-axis midesophageal bicaval view at end-diastole with electrocardiographic synchronization. Data were recorded during suspended ventilation, before and after leg elevation, and at different levels of positive end-expiratory pressure (0, 5, and 10 cmH(2)O)., Measurements and Main Results: The relationship between IVCD and CVP had 2 portions: A first (CVP 11 mmHg) in which the correlation was poor (R = 0.272, p = 0.065). No correlation between SVCD and CVP was observed., Conclusion: A strong correlation between TEE-derived IVCD measured at the point of entry into the right atrium and CVP was observed in cardiac surgical patients when CVP was

Objective: Left ventricular (LV) hypertrophy is associated with increased diastolic chamber stiffness early after aortic valve replacement for valve stenosis. Enoximone, a phosphodiesterase III inhibitor, has been shown to improve myocardial contractility and relaxation when administered as a single dose after cardiac surgery. The present study investigated, by analysis of transmitral flow velocity patterns and end-diastolic pressure-area relations, whether enoximone administered before aortic valve surgery has an effect on LV diastolic properties., Design: Prospective, randomized study., Setting: Referral center for cardiothoracic surgery at a university hospital., Participants: Thirty-four patients undergoing aortic valve replacement for aortic stenosis., Interventions: Patients in the enoximone group (n = 17) received a bolus dose of 0.35 mg/kg (0.15 mg/kg before aortic cross-clamping and 0.2 mg/kg added to the cardioplegic solution). Individual pressure-area relations (pulmonary capillary wedge pressure v left ventricular end-diastolic area) were obtained by using volume loading by leg elevation before and after surgery with closed chest., Measurements and Main Results: The pressure-area relation on the pressure-area plot was shifted to the left after surgery, indicating decreased LV diastolic distensibility in the enoximone and control groups and providing evidence of decreased LV diastolic function. Indices of LV diastolic chamber stiffness, LV operating stiffness (K(LV)) derived from the deceleration time of early ventricular filling, and the constant of chamber stiffness (beta) derived from pressure-area relations were not different after enoximone treatment. Systolic LV function was unaltered after cardiac surgery in both groups. Analysis of changes in transmitral flow patterns identified an increased atrial filling fraction in enoximone-treated patients, suggesting increased atrial systolic function. The unaltered systolic pulmonary venous flow velocity compared with the decrease in the control group after volume loading further supports preservation of left atrial reservoir function with enoximone in the absence of evidence for decreased LV stiffness., Conclusion: Preemptive enoximone did not change LV diastolic function based on diastolic filling patterns or LV stiffness indices (K(LV) and beta) derived from Doppler early filling deceleration time and pressure-area relations. Doppler data suggested improvement of left atrial systolic function and preservation of left atrial reservoir function with enoximone.

Objective: The purpose of this study was to compare the effects of a total intravenous and a volatile anesthetic regimen on biochemical markers of hepatic and renal dysfunction after coronary artery surgery., Design: Prospective, double-blind, randomized clinical study., Setting: University hospital, single institutional., Participants: Three hundred twenty patients undergoing elective coronary artery surgery were divided into 2 different anesthetic protocols: propofol group (n = 160) and sevoflurane group (n = 160)., Interventions: Hemodynamic data were registered before the start of surgery, before the start of CPB, 15 minutes after the end of CPB, at arrival in the intensive care unit, and 6 and 12 hours after arrival in the intensive care unit. Serum glutamic oxaloacetic transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), serum lactate dehydrogenase (LDH), and serum creatinine concentrations were measured before surgery, at arrival in the intensive care unit, and after 6, 12, 24, and 48 hours., Measurements and Main Results: Postoperative levels of serum SGOT, SGPT, and LDH increased transiently in both anesthetic groups, but the increase was significantly lower in the sevoflurane group compared with the propofol group. Creatinine levels remained largely unchanged in both groups., Conclusion: Postoperative biochemical markers of hepatic dysfunction were lower with a sevoflurane-based anesthetic regimen in patients undergoing coronary artery surgery with cardiopulmonary bypass.

Objective: The purpose of this study was to compare dP/dt(max) estimated from a femoral artery pressure tracing to left ventricular (LV) dP/dt(max) during various alterations in myocardial loading and contractile function., Participants: Seventy patients scheduled for elective coronary artery bypass surgery., Methods: All patients were instrumented with a high-fidelity LV catheter, a pulmonary artery catheter, and a femoral arterial catheter. In 40 patients, hemodynamic measurements were performed before and after passive leg raising and before and after calcium administration (5 mg/kg); and in 30 other patients, hemodynamic measurements were performed before and after dobutamine infusion (5 microg/kg/min over 10 minutes)., Results: LV and femoral dP/dt(max) were significantly correlated (r = 0.82, p < 0.001), but femoral dP/dt(max) systematically underestimated LV dP/dt(max) (bias = -361 +/- 96 mmHg/s). Passive leg raising induced significant increases in central venous pressure and LV end-diastolic pressure, but femoral dP/dt(max), stroke volume, and LV dP/dt(max) remained unaltered. Calcium administration induced significant and marked increases in LV dP/dt(max) (23% +/- 9%) and femoral dP/dt(max) (37% +/- 14%) associated with a significant increase in stroke volume (9% +/- 2%). Dobutamine infusion also induced significant and marked increases in LV dP/dt(max) (25% +/- 8%) and femoral dP/dt(max) (35% +/- 12%) associated with a significant increase in stroke volume (14% +/- 3%). Overall, a very close linear relationship (r = 0.93) and a good agreement (bias = -5 +/- 17 mmHg/s) were found between changes in LV dP/dt(max) and changes in femoral dP/dt(max). A very close relationship was also observed between changes in LV dP/dt(max) and changes in femoral dP/dt(max) during each intervention (leg raising, calcium administration, and dobutamine infusion)., Conclusion: Femoral dP/dt(max) underestimated LV dP/dt(max), but changes in femoral dP/dt(max) accurately reflected changes in LV dP/dt(max) during various interventions.