Risultati immediati ed a distanza del bypass aorto-coronarico eseguito in pazienti con contrattilit\ue0 cardiaca compromessa

From March 1979 to December 1985 at Cardiac Surgery Department of Parma 1064 patients underwent myocardial revascularization. Of them, 82 (7.7%) with poor left ventricular function (ejection fraction less than 40%) were studied to evaluate the effects of coronary artery bypass grafting on surgical risk, survival, ventricular performance and late clinical status. Three vessels disease was present in 65.9% and severe stenosis of left main coronary artery in 21.9% of patients. There were 74 (90.2%) patients with a history of previous myocardial infarction and 8 (9.75%) with congestive heart failure. Mean ejection fraction was 32.21 +/- 3.6%. On biplane left ventricular angiography 60 (73.2%) cases had two or more akinetic segments and 22 (21.9%) only hypokinesia. Operative mortality rate was 4.9%; perioperative myocardial infarction occurred in 5 patients (6.2%). Mean follow-up was 37.64 +/- 9.23 months and survival rate, including operative mortality, was 91.3%. Among the long-term survivors 89.04% are asymptomatic and in 49% there was a significantly improvement of preoperative left ventricular ejection fraction. We conclude that myocardial revascularization should be performed also in patients with left ventricular dysfunction, because of improvement of quality of life

Early and long-term results of coronary artery bypass grafting in patients with poor left ventricular function.

The case is described of a fifty year old man who underwent coronary bypass surgery using the circular sequential vein graft technique. At follow-up study (6 months after operation), despite his asymptomatic status, the effort test revealed antero-lateral myocardial ischemia. A coronary angiography showed a 90% proximal stenosis of the graft at 1.5 cm from the aortic anastomosis. The patient was reoperated on and the circular graft was reconstructed. Despite the severe stenosis this technique of myocardial revascularization has developed intercoronary anastomoses, improving the cardiac contractility and avoiding further clinical complications

Early and long-term results of coronary artery bypass grafting in patients with poor left ventricular function.

The case is described of a fifty year old man who underwent coronary bypass surgery using the circular sequential vein graft technique. At follow-up study (6 months after operation), despite his asymptomatic status, the effort test revealed antero-lateral myocardial ischemia. A coronary angiography showed a 90% proximal stenosis of the graft at 1.5 cm from the aortic anastomosis. The patient was reoperated on and the circular graft was reconstructed. Despite the severe stenosis this technique of myocardial revascularization has developed intercoronary anastomoses, improving the cardiac contractility and avoiding further clinical complications

Structural characterization of recombinant crustacyanin subunits from the lobster Homarus americanus

Crustacean crustacyanin proteins are linked to the production and modification of carapace colour, with direct implications for fitness and survival. Here, the structural and functional properties of the two recombinant crustacyanin subunits H(1) and H(2) from the American lobster Homarus americanus are reported. The two subunits are structurally highly similar to the corresponding natural apo crustacyanin CRTC and CRTA subunits from the European lobster H. gammarus. Reconstitution studies of the recombinant crustacyanin proteins H(1) and H(2) with astaxanthin reproduced the bathochromic shift of 85-95 nm typical of the natural crustacyanin subunits from H. gammarus in complex with astaxanthin. Moreover, correlations between the presence of crustacyanin genes in crustacean species and the resulting carapace colours with the spectral properties of the subunits in complex with astaxanthin confirmed this genotype-phenotype linkage

Efficacy of multimodal neuromonitoring by transcranial doppler and EEG to assess cerebral hemodynamic changes during cardiopulmonary bypass.

The overall incidence of neurological complications in cardiac surgery is 3-5%. The most important mechanisms involved in neurological damage during cardiopulmonary bypass (CPB) are global or focal hypoperfusion and embolic phenomena. While most neuromonitoring studies highlighted the role of embolism during CPB, only a few studies focused on the relationship between cerebral hemodynamic changes and neurological outcome. We developed a study protocol based on intraoperative bilateral continuous monitoring of middle cerebral arteries by transcranial doppler (TCD) and digital 32-channel EEG recording (10-20 system). Patients underwent clinical, neuropsychological, TCD and EEG evaluation at baseline and postoperatively at the 2 "d, 7 th and 30 th day. Including criteria were: age < 75 years, number of vascular risk factors < 3, absent history of cerebral ischemic attacks, no significant intracranial and/or extracranial carotid plaques on carotid color duplex and TCD, no significant cognitive dysfunction. Eight patients were recruited and 4 ofthem, submitted to coronary-aortic bypass, could undergo the complete protocol study. Four patients were excluded from the intraoperative monitoring: 2 cases due to abad temporal windows for TCD study, 1 case for a significant carotid plaque, and 1 case for a sudden worsening of cardiac conditions. In all patients, we found a significant increase of mean cerebral blood flow velocity (CBFV) soon after the aortic clamping and during the whole phase of extracorporeal circulation. CBFV remained significantly higher than basal values also after aortic decannulation, despite a transient decrease at the clamping removal. EEG showed diffuse slowing and voltage reduction in all patients, suggesting cerebral hypoperfusion. The apparent contradictory changes of TCD andEEG could be explained by a pseudo-inflammatory reaction leading to a concomitant arteriolar vasodilatation and impaired blood-tissue exchange with neuronal dysfunction. Mean arterial blood pressure decreased during CPB and returned to basal values soon after aortic decannulation. This suggested that CBFV and arterial blood pressure changed independently and that a merely loss of cerebral autoregulation did not occur. Our on-progress study indicated that multimodal neuromonitoring provided interesting data on pathophysiological mechanisms during CP

Hemodynamic and respiratory effects of medium-chain and long-chain triglyceride fat emulsions: A prospective, randomized study

Background: Intravenous fat emulsions (IVFE) containing long-chain triglycerides (LCTs) (chain length 20 carbon atoms) have been associated with adverse hemodynamic and respiratory effects in postoperative on intensive care unit patients. Recently, medium-chain triglycerides (MCTs) (chain length 6 to 12 carbons atoms) have been introduced as a component of IVFE. Objectives: The study was aimed at comparing cardiopulmonary effects of IVFE with different composition (MCTs + LCTs vs LCT-based IVFE). Design: Prospective, double-blind, randomized, parallel-group controlled trial. Setting: Heart surgery postoperative intensive care unit. Patients: With approval of the Institutional Review Board of Human Studies, and after obtaining written informed consent, twenty-six spontaneously breathing patients were enrolled in the study 24 hours after open heart surgery for mitral valve replacement (22 females, 4 males, mean age 57 years, range 35-73). Interventions: Patients were randomized into two groups, to receive 1 mL/kg/hour for two hours (3.3 mg/kg/min) of the LCT-based IVFE or the IVFE containing a physical mixture of MCTs + LCTs (50:50%). Group comparisons were made using repeated measures of ANOVA; main statistical comparisons were made in each group between baseline values and data collected during and after two hours of IVFE infusion (Dunnett multiple comparison test). A p < .05 level was used to establish statistical significance. Measurements and main results: In each group hemodynamic measurements and arterial blood gases were obtained before, during and after (for another two hours) IVFE infusion, at 30' intervals; oxygen transport/utilization parameters and intrapulmonary shunt fraction were also calculated. No change in heart rate, cardiac index, systemic and pulmonary pressures or resistance, central venous and pulmonary capillary pressures, nor in arterial blood gases was observed in the MCTs + LCTs group, as compared to pre-infusion values. IVFE administration reduced the cardiac index (-15% at 60' and 120' of infusion) only in the group receiving the LCT-based IVFE; significant increases in both pulmonary artery pressures and vascular resistances were observed in the same group, with PaO2 decrease during IVFE administration. Oxygen consumption was constantly increased (+15% vs baseline values) during and after MCTs + LCTs infusion. Oxygen delivery was unmodified by LCTs + MCTs, but it was significantly reduced by the LCT-based IVFE. Neither changes in the intrapulmonary shunt fraction nor arrhythmias or adverse clinical reactions were observed during or after the infusion of either IVFE. Conclusions: Unlike IVFE based on LCTs only, MCTs + LCTs IVFE do not exert adverse cardiopulmonary effects at clinically useful doses following valvular heart surgery and could represent a safe source of rapidly metabolized substrates

Hemodynamic, respiratory, and metabolic effects of medium-chain triglyceride-enriched lipid emulsions following valvular heart surgery

Study: A lipid emulsion containing 10 percent medium-chain triglycerides (MCT) and 10 percent long-chain triglycerides (LCT) was infused at a rate of 1 ml/kg/h (3.3 mg/kg/min) for 2 h, in 12 patients (2 males, 10 females; mean age, 54 ± 3 (SEM) years; range, 34 to 67 years) 24 h after open-heart surgery (mitral valve replacement). Methods: Hemodynamic factors (pulmonary and radial artery indwelling catheters), oxygen and carbon dioxide partial pressures, oxygen saturation, oxygen delivery and consumption, and intrapulmonary shunt fraction were obtained before, during, and after lipid infusion (for 2 h), at 30-s intervals, along with some metabolic indexes (triglycerides, free fatty acids, glucose, insulin, lactate, acetoacetate). Results: No statistically significant changes in heart rate, cardiac index, systemic and pulmonary pressures and resistances, central venous and pulmonary capillary pressures, or arterial oxygen partial pressure were observed during infusion. Arterial carbon dioxide partial pressure values were constantly reduced throughout and after the end of lipid infusion, as compared with baseline values, while oxygen consumption was increased significantly without any change in oxygen delivery. No adverse effects on intrapulmonary shunt fraction were observed. Statistically significant increases of triglycerides, free fatty acids, acetoacetate and insulin (peak values at end of the lipid infusion) were found in comparison with baseline values. Plasma glucose increased significantly during lipid infusion and remained higher than baseline values until the end of the study. Lactate levels were unchanged, except for a slight decrease at the end of the study, without any derangement of acid-base equilibrium. Neither arrhythmias nor adverse clinical reactions were observed as a consequence of lipid infusion. Conclusion: Fat emulsions containing both MCT and LCT, when given at 3.3 mg/kg/min for 120 min following valvular heart surgery, do not exert negative cardiopulmonary effects, and could represent a source of rapidly metabolized substrates

Hemodynamic, respiratory, and metabolic effects of medium-chain triglyceride-enriched lipid emulsions following valvular heart surgery

Study: A lipid emulsion containing 10 percent medium-chain triglycerides (MCT) and 10 percent long-chain triglycerides (LCT) was infused at a rate of 1 ml/kg/h (3.3 mg/kg/min) for 2 h, in 12 patients (2 males, 10 females; mean age, 54 \ub1 3 (SEM) years; range, 34 to 67 years) 24 h after open-heart surgery (mitral valve replacement). Methods: Hemodynamic factors (pulmonary and radial artery indwelling catheters), oxygen and carbon dioxide partial pressures, oxygen saturation, oxygen delivery and consumption, and intrapulmonary shunt fraction were obtained before, during, and after lipid infusion (for 2 h), at 30-s intervals, along with some metabolic indexes (triglycerides, free fatty acids, glucose, insulin, lactate, acetoacetate). Results: No statistically significant changes in heart rate, cardiac index, systemic and pulmonary pressures and resistances, central venous and pulmonary capillary pressures, or arterial oxygen partial pressure were observed during infusion. Arterial carbon dioxide partial pressure values were constantly reduced throughout and after the end of lipid infusion, as compared with baseline values, while oxygen consumption was increased significantly without any change in oxygen delivery. No adverse effects on intrapulmonary shunt fraction were observed. Statistically significant increases of triglycerides, free fatty acids, acetoacetate and insulin (peak values at end of the lipid infusion) were found in comparison with baseline values. Plasma glucose increased significantly during lipid infusion and remained higher than baseline values until the end of the study. Lactate levels were unchanged, except for a slight decrease at the end of the study, without any derangement of acid-base equilibrium. Neither arrhythmias nor adverse clinical reactions were observed as a consequence of lipid infusion. Conclusion: Fat emulsions containing both MCT and LCT, when given at 3.3 mg/kg/min for 120 min following valvular heart surgery, do not exert negative cardiopulmonary effects, and could represent a source of rapidly metabolized substrates