Utjecaj kontinuirane infuzije inzulina na lučenje endotelina-1 tijekom operacije aortokoronarnog premoštenja u bolesnika sa šećernom bolešću [Influence of continuous insulin infusion on endothelin-1 expression during coronary artery bypass grafting in diabetics]

Background: Endothelial dysfunction (ED) accelerates atherosclerosis in diabetics. ET-1 is one of the most potent vasoconstrictors and a marker of endothelial dysfunction (ED). Hyperglycemia and cardiopulmonary bypass (CPB) exacerbate ED which can be prevented by perioperative gycemic control. Methods: Fourty-seven diabetics undergoing elective surgical myocardial revascularization were randomized to perioperative glycemic controll by bolus (BOL) or continuous insulin infusion (KII). Systemic and coronary blood samples were obtained at predefined time points. Insulin rates were applied according to protocols. ET-1 levels were determined by ELISA. During and after procedure hemodynamic parameters, myocardial damage markers and clinical outcomes were measured. Results: Continuous insulin infusion (KII) significantly reduced ET-1 expression in systemic F(1,45)= 6,873; p=0,012, but not in coronary circulation BOL 5,00±1,22 vs KII 4,36±1,06; p=0,062. KII obtained better gycemic control in postoperative period (p=0,008) and reduced overall GUK during observed time period : F(1,45)=13,132; p=0,001. There were no differences in systemic inflammatory response, myocardial damage or clinical outcomes. Conclusion: KII reduces ET-1 expression in diabetics undergoing myocardial revascularization with CPB in systemic but not coronary circulation. Effect is most likely due to better and more stable gycemia control and avoidance of hyperglycemia. Overall glycemic control was better in KII group with no effect on clinical outcomes

Off-pump coronary bypass surgery adversely affects alveolar gas exchange

While the introduction of off-pump myocardial revascularization (OPCAB) has initially shown promise in reducing respiratory complications inherent to conventional coronary surgery, it has failed to eradicate them. Our study focused on quantifying the lactate release from the lungs and the dysfunction at the level of the alveolar-capillary membrane precipitated by OPCAB at different time points after the insult. Furthermore, we aimed to determine the impact of pulmonary lactate production on systemic lactic acid concentrations. The study was conducted in a prospective observational fashion. Forty consecutive patients undergoing OPCAB were analyzed. The mean patient age was 60 +/- 10 years. The mean EUROScore was 3.8 +/- 2.9. The alveolar-arterial O2 gradient increased from 19 [range 9 to 30] to 26 [range 20 to 34] kPa (P < 0.001) and remained elevated up to 6 hours after surgery. It rapidly declined again by 18 hours postoperatively. The observed increase in the pulmonary lactate release (PLR) from a baseline value of 0.022 [range -0.074 to 0.066] to 0.089 [range 0.016 to 0.209] mmol/min/m2 at six hours postoperatively did not reach statistical significance (P = 0.105). The systemic arterial lactate (Ls) concentration increased from 0.94 [range 0.78 to 1.06] to 1.39 [range 0.97 to 2.81] mmol/L (P < 0.001). The venoarterial pCO2 difference showed no significant change in comparison to baseline values. The mortality in the studied group was 2.5% (1/40). The pulmonary lactate production showed a statistically significant correlation with the systemic lactate concentration (R = 0.46; P = 0.003). Pulmonary injury following off pump myocardial revascularization was evidenced by a prompt increase in the alveolar-arterial oxygen gradient. The alveolar-arterial O2 gradient correlated with the duration of mechanical ventilation

Topical use of antifibrinolytic agents reduces postoperative bleeding: a double-blind, prospective, randomized study

Objective: Postoperative bleeding is still one of the most common complications of cardiac surgery. Antifibrinolytic agents successfully reduce bleeding, but there are controversies concerning adverse effects after their systemic use. By topical application of antifibrinolytic agents in pericardial cavity, most of these effects are avoided. We compared the effects of topically applied aprotinin, tranexamic acid and placebo on postoperative bleeding and transfusion requirements. - - - - - Methods: In this single-center prospective, randomized, double-blind trial, 300 adult cardiac patients were randomized into three groups to receive one million IU of aprotinin (AP group), 2.5g of tranexamic acid (TA group) or placebo (PL group) topically before sternal closure. Groups were comparable with respect to all preoperative and intraoperative variables. Postoperative bleeding, transfusion requirements and hematologic parameters were evaluated. - - - - - Results: Postoperative bleeding within first 12-h period (AP group 433+/-294 [350; 360]ml, TA group 391+/-255 [350; 305]ml, PL group 613+/-505 [525; 348]ml), as well as cumulative blood loss within 24h (AP group 726+/-432 [640; 525]ml, TA group 633+/-343 [545; 335]ml, PL group 903+/-733 [800; 445]ml), showed statistically significant inter-group differences (both p<0.001). Bleeding rates values were significantly higher in placebo group compared to the groups treated with antifibrinolytic agents (AP and TA groups) concerning both variables. Although TA group showed the lowest values, no statistical differences between TA and AP groups were found. Inter-group difference of blood product requirements was not statistically significant. - - - - - Conclusions: Topical use of either tranexamic acid or aprotinin efficiently reduces postoperative bleeding. TA seems to be at least as potent as aprotinin, but potentially safer and with better cost-effectiveness ratio

Ehokardiografija u otkrivanju endokarditisa izazvanog ugradnjom elektrode implantabilnog kardioverter defibrilatora: prikaz slučaja

Lead endocarditis is an infrequent but potentially lethal complication of implantable cardioverter defibrillator (ICD) implantation. We report a case of a 53-year-old man with ICD who was admitted to our hospital because of fever, chills, shivering, headache and malaise. Transthoracic echocardiography detected a structure highly suspect of vegetation located on the ICD lead. Transesophageal echocardiography showed a 20x12 mm mobile vegetation attached to the ICD lead in the right atrium. The infection was caused by methicillin-resistant Staphylococcus epidermidis (MRSE), which was isolated from blood cultures. Treatment consisted of surgical removal of the ICD lead and placement of new epicardial ICD leads. Three years afterwards, the patient remained asymptomatic. To our knowledge, this is the first such case reported from Croatia.Endokarditis elektrode je rijetka no potencijalno smrtonosna komplikacija ugradnje implantabilnog kardioverter defibrilatora (ICD). Prikazujemo slučaj 53 godine starog muškarca s implantiranim ICD-om koji je hospitaliziran zbog febriliteta, groznice, tresavice i općeg lošeg stanja. Transtorakalnim ultrazvukom srca je otkrivena tvorba vrlo sumnjiva na vegetaciju na elektrodi ICD-a, da bi transezofagusnim ultrazvukom bila prikazana vegetacija veličine 20x12 mm pričvršćena za elektrodu ICD-a u desnom atriju. Uzročnik endokarditisa je bio meticilin rezistentni Staphylococcus epidermidis (MRSE) koji je izoliran u hemokulturi. Liječenje se sastojalo od kirurškog odstranjenja elektrode ICD-a i njene zamjene novim, epikardijalnim elektrodama. Tri godine kasnije bolesnik je i dalje bez tegoba. Prema našim saznanjima, ovo je prvi ovakav slučaj dosad opisan u Hrvatskoj

A case of right heart failure in a 48-year-old patient with constrictive pericarditis treated by pericardiectomy

Background: Constrictive pericarditis (CP) is uncommon cause of predominantly right heart failure1. In CP pericardium creates a stiff ventricular-pericardial unit which leads to increased diastolic pressures, limitation of ventricular relaxation and equalization of intracardiac diastolic pressures producing „single diastolic chamber”2. Case report: 48-years-old male was admitted to Department of Gastroenterology for the investigation of upper abdominal pain. Investigations showed deranged liver biochemistry tests and computed tomography showed widespread ascites and small pleural effusion. Abdominal ultrasonography showed increased size of liver with dilated hepatic veins. The patient was referred to a cardiologist. A transthoracic echocardiogram (TEE) showed normal both ventricular dimensions, dyskinetic motion of intraventricular septum, small pericardial effusion without thickened pericardium. Inferior vena cava (IVC) was dilated with minimal respiratory variation. Because of nonconclusive TTE further diagnostic test including cardiac magnetic resonance imaging (MRI) was recommended. The patient was treated with diuretics and was discharged from hospital after clinical improvement. After three months he was admitted to Department of cardiology with signs and symptoms of right heart failure. On this admission, TTE showed paradoxical cardiac septal motion (“septal bounce”). Doppler inflow study showed respiratory variations of E-wave in mitral inflow (decreased >25% during inspiration) and increased E-wave during inspiration in tricuspid inflow. Pericardium was thickened (7mm) now without pericardial effusion. Estimated pulmonary artery pressure was around 40mmHg. The IVC was dilated without respiratory variation. MRI showed intensive T2 signal on pericardium, late gadolinium enhancement: pathologic imbibition in thickened pericardium. Right heart catheterization showed prominent x-descent and y descent, “square root“ sign, drop of left ventricular pressure and increased right ventricular pressure during inspiration, equalization of left ventricular end-diastolic pressure and end-diastolic right ventricular pressure (16mmHg). This finding was consistent with constrictive pericarditis. The patient was referred to a cardiothoracic surgeon and underwent a successful pericardiectomy. Conclusion: CP should be considered in all patients with unexplained right heart failure. Because diagnosis is sometimes difficult to establish it may be necessary to use multiple diagnostic tools