Resveratrol as antioxidant in cardiac surgery: is there potential for clinical application?

Cardiopulmonary bypass (CPB) is an essential technique in cardiac surgery but is also associated with adverse effects, including the systemic inflammatory response syndrome that manifests itself as ischaemia-reperfusion injury and multi-organ dysfunction. The aim of this mini review is to take a look at the current knowledge of resveratrol, a stilbenoid and natural antioxidant believed to have many cardioprotective effects including vasodilation, lowering of blood pressure and reactive oxygen species levels, suppression of low-density lipoprotein peroxidation, and mitigation of ischaemia/-reperfusion injury. We mostly focus on its cardioprotective potential in patients undergoing cardiac surgery supported by CPB. Current findings, however, are still inconclusive and call for further research, including clinical trials.

Postpericardiotomy syndrome incidence, diagnostic and treatment strategies: experience AT two collaborative centers.

Postpericardiotomy syndrome (PPS) is worsening or new formation of pericardial and/or pleural effusion mostly 1 to 6 weeks after cardiac surgery, as a result of autoimmune inflammatory reaction within pleural and pericardial space. Its incidence varies among different studies and registries (2% to 30%), as well as according to the type of cardiac surgery performed. We conducted this retrospective analysis of PPS incidence and diagnostic and treatment strategies in patients referred for cardiac surgery for revascularization, valvular and/or aortic surgery. We retrospectively analyzed 461 patients referred for an urgent or elective cardiac surgery procedure between 2009 and 2015. PPS diagnosis was established using well defined clinical criteria. Demographic and clinical characteristics were used in regression subanalysis among patients having undergone surgery of aortic valve and/or ascending aorta. Within 6 weeks after cardiac surgery, 47 (10.2%) patients had PPS. The median time from the procedure to PPS diagnosis was 14 days. The incidence of PPS was 26% after aortic valve and/or aorta surgery, and 7.9% and 8.3% after coronary bypass and mitral valve surgery, respectively. Among patients subjected to aortic valve and/or aortic surgery, regression analysis showed significant association of fever, C-reactive protein (CRP) elevation between 5 and 100 mg/L, urgent procedure and postoperative antibiotic use with PPS diagnosis, whereas younger age showed near-significant association. All patients had complete resolution of PPS, mostly after corticosteroid therapy, with only 2 cases of recurrent PPS that successfully resolved after colchicine therapy. Pleural drainage was indicated in 15 (32%) patients, whereas only one patient required pericardial drainage. In conclusion, PPS incidence in our retrospective analysis was similar to previous reports. Patients having undergone aortic valve and/or aortic surgery were most likely to develop PPS. The most relevant clinical criteria for diagnosis in these patients were fever, CRP elevation between 5 and 100 mg/L, and pericardial and/or pleural effusion formation or worsening 2 weeks after cardiac surgery.

The Dark Side of the Heart: Cardiovascular Manifestation of Ochronosis.

Alkaptonuria is rare genetic disorder of tyrosine metabolism manifesting with signs of tissue pigmentation, dark urine, and ochronotic arthropathies. Commonly undiscovered by late adulthood, alkaptonuria can manifest as cardiac ochronosis with cardiovascular disorders such as valvulopathies, but rarely coronary artery disease. This case report describes 2 patients with aortic stenosis and coronary artery disease in whom alkaptonuria was diagnosed during open heart surgery.

Heart re-transplantation in Eurotransplant.

Internationally 3% of the donor hearts are distributed to re-transplant patients. In Eurotransplant, only patients with a primary graft dysfunction (PGD) within 1 week after heart transplantation (HTX) are indicated for high urgency listing. The aim of this study is to provide evidence for the discussion on whether these patients should still be allocated with priority. All consecutive HTX performed in the period 1981-2015 were included. Multivariate Cox' model was built including: donor and recipient age and gender, ischaemia time, recipient diagnose, urgency status and era. The study population included 18 490 HTX, of these 463 (2.6%) were repeat transplants. The major indications for re-HTX were cardiac allograft vasculopathy (CAV) (50%), PGD (26%) and acute rejection (21%). In a multivariate model, compared with first HTX hazards ratio and 95% confidence interval for repeat HTX were 2.27 (1.83-2.82) for PGD, 2.24 (1.76-2.85) for acute rejection and 1.22 (1.00-1.48) for CAV (P < 0.0001). Outcome after cardiac re-HTX strongly depends on the indication for re-HTX with acceptable outcomes for CAV. In contrast, just 47.5% of all hearts transplanted in patients who were re-transplanted for PGD still functioned at 1-month post-transplant. Alternative options like VA-ECMO should be first offered before opting for acute re-transplantation.

Isolated Tricuspid Valve Libman-Sacks Endocarditis in Systemic Lupus Erythematosus with Secondary Antiphospholipid Syndrome.

Libman-Sacks endocarditis, one of the most prevalent cardiac presentations of systemic lupus erythematosus, typically affects the aortic or mitral valve; tricuspid valve involvement is highly unusual. Secondary antiphospholipid syndrome increases the frequency and severity of cardiac valvular disease in systemic lupus erythematosus. We present the case of a 47-year-old woman with lupus and antiphospholipid syndrome whose massive tricuspid regurgitation was caused by Libman-Sacks endocarditis isolated to the tricuspid valve. In addition, we discuss this rare case in the context of the relevant medical literature.

Successful treatment of annular rupture during transcatheter aortic valve implantation.

Annular rupture presents a rare but potentially fatal complication of transcatheter aortic valve implantation (TAVI). Although it can be subtle and subclinical in presentation, most severe forms present with hemodynamic instability and represent true emergencies requiring a more invasive treatment, even conventional surgery. We present a case of successful treatment of annular rupture by left ventricular outflow tract patch and surgical aortic valve replacement.

Cardiac surgery-associated acute kidney injury: risk factors analysis and comparison of prediction models.

OBJECTIVES: Cardiac surgery-associated acute kidney injury (AKI) is a well-known factor influencing patients' long-term morbidity and mortality. Several prediction models of AKI requiring dialysis (AKI-D) have been developed. Only a few direct comparisons of these models have been done. Recently, a new, more uniform and objective definition of AKI has been proposed [Kidney Disease: Improve Global Outcomes (KDIGO)-AKI]. The performance of these prediction models has not yet been tested. METHODS: Preoperative demographic and clinical characteristics of 1056 consecutive adult patients undergoing cardiac surgery were collected retrospectively for the period 2012-2014. Multivariable logistic regression analysis was used to determine the independent predictors of AKI-D and the KDIGO-AKI stages. Risk scores of five prediction models were calculated using corresponding subgroups of patients. The discrimination of these models was calculated by the c-statistics (area under curve, AUC) and the calibration was evaluated for the model with the highest AUC by calibration plots. RESULTS: The incidence of AKI-D was 3.5% and for KDIGO-AKI 23% (17.3% for Stage 1, 2.1% for Stage 2 and 3.6% for Stage 3). Older age, atrial fibrillation, NYHA class III or IV heart failure, previous cardiac surgery, higher preoperative serum creatinine and endocarditis were independently associated with the development of AKI-D. For KDIGO-AKI, higher body mass index, older age, female gender, chronic obstructive pulmonary disease, previous cardiac surgery, atrial fibrillation, NYHA class III or IV heart failure, higher preoperative serum creatinine and the use of cardiopulmonary bypass were independent predictors. The model by Thakar et al. showed the best performance in the prediction of AKI-D (AUC 0.837; 95% CI = 0.810-0.862) and also in the prediction of KDIGO-AKI stage 1 and higher (AUC = 0.731; 95% CI = 0.639-0.761), KDIGO-AKI stage 2 and higher (AUC = 0.811; 95% CI = 0.783-0.838) and for KDIGO-AKI stage 3 (AUC = 0.842; 95% CI = 0.816-0.867). CONCLUSIONS: The performance of known prediction models for AKI-D was found reasonably well in the prediction of KDIGO-AKI, with the model by Thakar having the highest predictive value in the discrimination of patients with risk for all KDIGO-AKI stages.

Does Diabetes Have an Influence on Regional Deformation Parameters in Patients with Normal Systolic Function during Off-Pump Coronary Artery Bypass Grafting?

OBJECTIVES: The aim of this study was to assess the recovery of regional myocardial function of the left-ventricular septal wall and the septal site of the mitral valve (MV) annulus by tissue Doppler imaging (TDI). METHODS: In 63 (32 diabetic and 31 control) patients having off-pump coronary artery bypass grafting (OPCABG), including the left internal mammary artery (LIMA) and the left anterior descending coronary artery (LAD), TDI measurements were performed before operation (baseline), 5 min after LIMA-LAD revascularization (early reperfusion) and after completion of all anastomoses (after revascularization). RESULTS: Compared to the patients with diabetes, the controls had higher peak systolic velocities of the mid septal segments in the early reperfusion measurement (p = 0.002). After revascularization, values of peak systolic strain at the basal (-10.13 vs. -13.36%, p = 0.044) and mid septal segments (-8.25 vs. -12.69%, p = 0.009) were decreased in the diabetic patients compared to the controls. There was no difference between the groups with respect to the velocities acquired at the septal site of the MV annulus. CONCLUSIONS: This study demonstrates an insufficient recovery of regional myocardial function in patients with type II diabetes undergoing OPCABG.

Off-pump myocardial revascularization attenuates endothelin-1 expression in systemic, pulmonary, and coronary circulation.

OBJECTIVE: The objective of this study was to evaluate the influence of cardiopulmonary bypass (CPB) on endothelin-1 (ET-1) expression in various circulation compartments in patients undergoing myocardial revascularization. METHODS: A total of 30 patients were randomized to undergo myocardial revascularization with (CABG, n = 15) or without (OPCAB, n = 15) CPB. Samples were taken preoperatively, after establishing CPB and after CPB (CABG group), prior to and after revascularization (OPCAB group), and 6 and 24 h postoperatively. Values of ET-1 were compared between groups at all time points and correlated with postoperative cardioselective enzyme values and clinical parameters. RESULTS: In OPCAB group, ET-1 levels did not significantly vary between time points. In CABG group, ET-1 levels were significantly elevated vs. baseline in arterial: ART-T2 vs. ART-T0 (1.83 ± 1.81 vs. 0.76 ± 1.07 fmol/mL, p = 0.05), pulmonary: SG-T2 vs. SG-T0 (2.70 ± 2.75 vs. 0.39 ± 0.28 fmol/mL, p < 0.001) and SG-T3 vs. SG-T0 (1.56 ± 0.28 vs. 0.39 ± 0.28 fmol/mL, p < 0.001), and coronary circulation CS-T2 vs. CS-T1 (1.12 ± 0.49 vs. 0.27 ± 0.09 fmol/mL, p = 0.01). ET-1 levels were significantly higher in CABG group in all vascular compartments: ART-T2 (1.83 ± 1.81 vs. 0.17 ± 0.16 fmol/mL, p = 0.02), ART-T4 (0.99 ± 0.56 vs. 0.24 ± 0.12 fmol/mL, p = 0.01), SG-T1 (0.59 ± 0.15 vs. 0.25 ± 0.13 fmol/mL, p = 0.01), SG-T2 (2.70 ± 2.75 vs. 0.30 ± 0.24 fmol/mL, p = 0.004), SG-T3 (1.56 ± 0.28 vs. 0.35 ± 0.31 fmol/mL, p < 0.001), SG-T4 (1.34 ± 0.11 vs. 0.34 ± 0.16 fmol/mL, p < 0.001), and CS-T2 (1.12 ± 0.49 vs. 0.12 ± 0.12 fmol/mL, p = 0.004). Coronary sinus ET-1 level after CPB (CS-T2) in CABG group correlated positively with troponin-I level 24 h postoperatively (r(2) = 0.802, p = 0.02) CONCLUSION: Off-pump myocardial revascularization attenuates ET-1 expression in all investigated vascular compartments. Elevated coronary ET-1 levels after CPB in CABG group correlate with troponin-I levels 24 h postoperatively.

Aortic valve endocarditis in a transplanted heart after urethral instrumentation.

Endocarditis represents a rare but life-threatening condition after heart transplantation. Recent American Heart Association guidelines recognize cardiac transplant patients with valvulopathy as high risk for endocarditis, but acknowledge that there were not sufficient data to make a recommendation for prophylaxis. Also, genitourinary procedures were no longer considered a risk factor for endocarditis in the most recent guidelines. We present a patient who acquired aortic valve endocarditis of the intact valve, after multiple urethral instrumentation 2 years after heart transplantation, who was successfully treated by aortic valve replacement and prolonged antibiotic therapy.

Predictors of short-term neurocognitive outcome following coronary revascularisation (CABG) depending on the use of cardiopulmonary bypass.

The purpose of our study was to investigate the association between perioperative cerebral microembolization, expressed as high-intensity transient signals (HITS) and postoperative dynamics of the neuromarker S100P in patients operated using cardiopulmonary bypass, and to assess their impact upon the neurocognitive function in the early postoperative stage. The study involved 62 consecutive male patients aged 60 or above, alls scheduled for elective aortocoronary bypass. The patients were recruited from two groups with respect to the use of CPB: on-pump group (CPB+, N = 30) and off-pump group (CPB-, N = 32). In all patients we performed intraoperative monitoring of cerebral haemodynamics using transcranial Doppler, with the goal of quantifying perioperative cerebral microembolization. The serum levels of the neuromarker S100l were measured immediately after surgery, and then 12, 24 and 48 hours after the surgery. Neurocognitive status was assessed before and after the surgery and in three cognitive domains. Results of the study have shown that with respect to the short-term postoperative neurocognitive outcome there is no significant difference between the on-pump and off-pump surgical technique of coronary revascularization'. Perioperative cerebral microembolization was significantly more pronounced in the on-pump group yet it did not affect early postoperative neurocognitive function, while the increase in the neuromarker S100beta serum level 48 hours after surgery may have prognostic value as a predictor of postoperative neurocognitive dysfunction.

[Recovery after long-term pulsatile mechanical circulatory support in patient with chronic heart failure: a case report]. / Oporavak nakon dugotrajne mehanicke cirkulatorne potpore u bolesnika s kronicnim zatajivanjem srca: prikaz bolesnika.

Use of mechanical circulatory support (MCS) is a part of today's standard therapy in the treatment of end-stage heart failure. In this paper we describe characteristics of Thoratec pVAD device for MCS, implantation techniques, as well as the most important advantages and complications of application of the device. We present a 41-year-old patient with dilatated cardiomyopathy, who was the first recipient ofparacorporeal left ventricular assist device (LVAD) in the Republic of Croatia due to end-stage heart failure. After heart function recovery the patient was successfully weaned from MCS after 130 days of support.

Asymptomatic calcifying fibrous pseudotumor compressing heart cavities.

Calcifying fibrous pseudotumor is a rare benign lesion composed mostly of dense hyalinized colagen with multiple dystrophic or psammomatous calcifications and variable lymphoplasmacytic infiltrate. Children and young adults are most commonly affected by this tumor of uncertain pathogenesis. This is a case of an asymptomatic young woman with calcifying fibrous pseudotumor of the pericardium compressing heart cavities. Partial resection and marsupialization of the mass was performed.

[Frequency and characteristics of dyspepsia in coronary artery disease patients]. / Ucestalost i karakteristike dispepsije u bolesnika s koronarnom bolescu srca.

The aim of the study was to determine the frequency of functional and organic dyspepsia and possible predictors for organic dyspepsia in coronary artery disease (CAD) patients. The 150 patients (109 men; mean age 62.61 +/- 10.23 yr) undergoing coronary artery by-pass grafting because of stable pectoral angina due to significant CAD were enrolled in the study. Dyspepsia was determined by the existence of epigastralgy, heartburn, nausea and vomiting. Dyspepsia with endoscopic lesions was defined as organic, and dyspepsia with normal endoscopy was defined as functional. Multivariate analysis (logistic regression) was used to estimate predictive values of some independent clinical and demographic variables in relation to organic dyspepsia (dependent variable). One hundred thirty-five (90%) patients had at least one symptom of dyspepsia. Eighty five patients (63%) had organic dyspepsia, and 50 (37%) patients had functional dyspepsia (P < 0.001). Patients with organic dyspepsia had more dyspeptic symptoms than patients with functional dyspepsia (1.92 +/- 0.88 vs. 1.38 +/- 0.87, P < 0.001). More dyspeptic symptoms correlated with heavy GD lesions (r = 0.267; P < 0.0001). Multivariate analysis revealed independent correlation of consuming low-dose aspirin (standardized coefficient beta = 11.701, P = 0.004), diabetes (beta = 2.921, P = 0.027), cigarette smoking (beta = 2.910, P = 0.037) and nausea (beta = 3.620, P = 0.015) with organic dyspepsia. The study showed high frequency of dyspepsia, especially organic dyspepsia, in CAD patients. Three or more dyspeptic symptoms, low-dose aspirin, cigarette smoking, diabetes and nausea, increased the probability of organic dyspepsia. Therefore, for patients with combination of dyspeptic symptoms and present risk factors the endoscopic examination should be considered.

Long-term results after reconstructive surgery for aneurysms of the left ventricle.

BACKGROUND: Aneurysms of the left ventricle (LV) present a serious consequence of myocardial infarction, causing mechanical, thromboembolic, and arythmogenic complications. We present our experience in LV remodeling and long-term follow-up results. METHODS: From May 1998 to February 2009, 85 patients with postinfarction LV aneurysm underwent reconstructive procedures. Mean age was 58.7 + or - 8.9 years (range 36-79 years). Average LV ejection fraction was 39.8% + or - 13.1% (range 20%-70%). Mean EuroScore was 6.0 + or - 2.9 (range 3-19) and predictive mortality was 8.2% + or - 11.9% (range 1.6%-85.6%). The majority of patients were in New York Heart Association functional class II (44%) preoperatively and 32% of patients were in New York Heart Association class III or IV. LV reconstruction was performed by using the endoventricular patch technique in 56 patients (66%). In 29 patients (34%) reconstruction was done by linear closure. In 79 patients (93%) concomitant myocardial revascularization was performed. Mitral valve procedures were performed in 11 patients (13%), (repair in 10 patients and replacement in 1). RESULTS: Perioperative mortality was 3.5% (3 patients). Long-term follow-up was completed by means of phone interview with an average duration of 31.6 months (range 3-120 months). There were 9 late deaths (11%) during follow-up. Actuarial survival rates at 1, 5, and 10 years were 91%, 77%, and 68%, respectively. Fifty-nine patients (72%) were in New York Heart Association functional class I and II postoperatively. CONCLUSION: LV remodeling is a safe surgical procedure with low perioperative morbidity and mortality and excellent long-term survival, even in patients with severely reduced systolic function.

Pulmonary valve papillary fibroelastoma diagnosed by echocardiography: a case report.

Papillary fibroelastomas (PFEs) are rare cardiac valve tumours with reported incidence of <0.03% according to autopsy studies. Among them, pulmonary valve PFEs are extremely rare. With wider use of echocardiography, they are being increasingly recognized premortem. We describe a case of a 32-year-old Caucasian woman with PFE of pulmonic valve diagnosed by echocardiography. The patient underwent surgery due to high mobility of the tumour and high risk of embolic complications. The surgery was done with complete tumour resection and total preservation of valve function. This case report discusses diagnostics of PFEs, their characteristic echocardiographic and histological features, and possible complications and suggests treatment options in this rare cardiac tumour.

The association between upper gastrointestinal lesions and high-sensitivity C-reactive protein in coronary artery disease patients.

BACKGROUND: Although high-sensitivity C-reactive protein (hs-CRP) testing is not specific for coronary atherosclerosis, elevated hs-CRP is recently accepted as an independent predictor of future cardiovascular events. Also, a connection between upper gastrointestinal lesions (UGILs) and coronary artery disease (CAD) has been observed. The authors hypothesized that UGILs increase hs-CRP in CAD patients. MATERIAL/METHODS: One hundred fifty patients with stable CAD were enrolled in the study. Demographic and clinical variables and chronic medication used were gathered from a structured questionnaire. UGIL severity was determined by a modified Lanza score, H. pylori status by histology of the gastric mucosa, and the severity of CAD by a modified Gensini score. Independent correlation between hs-CRP and UGIL was tested by logistic regression analysis. RESULTS: The overall hs-CRP value was higher in patients with UGIL than in those with normal endoscopic results (8.14+/-4.53 mg/l vs. 4.64+/-3.06 mg/l, P<0.0001). hs-CRP level positively correlated with UGIL severity (r=0.434, P<0.0001). Correlation between UGIL and hs-CRP level remained significant after adjustment for coronary risk factors, medication used, CAD severity, and H. pylori status (standardized coefficient beta=1.272, P<0.0001). However, when hs-CRP level was used as a categorical variable, multivariate analysis revealed independent correlation only between UGIL and hs-CRP categories > or =6.1 mg/l. CONCLUSIONS: Elevated hs-CRP levels may be predictive of UGIL; thus endoscopy should be considered in CAD patients with elevated hs-CRP even with no dyspeptic symptoms. Because CRP plays an active role in atherothrombosis, UGILs with subsequent elevated CRP levels could increase cardiovascular risk in those patients.

[Gastroduodenal mucosal lesions and coronary atherosclerosis severity in patients with coronary artery disease]. / Ostecenje gastroduodenalne sluznice i tezina koronarne ateroskleroze u bolesnika s koronarnom bolescu srca.

AIM: Due to high metabolic activity and oxygen demands, ischemia of gastroduodenal (GD) mucosa is an important factor in the pathogenesis of its impairment. Comparing the degree of coronary atherosclerosis, for evaluation of severity of atherosclerosis, with the prevalence and severity of GD mucosal lesions, we wanted to investigate the possible ischemia of GD mucosa could contribute to its impairment. PATIENTS AND METHODS: This prospective study included 150 coronary artery disease (CAD) patients, 109 (72.7%) male and 41 (27.3%) female, average age 62.61 +/- 10.23 years. We noted clinical and anthropometric parameters, standard laboratory findings, treatment until inclusion into the study and standard cardiovascular risk factors. The severity of CAD was assessed by several parameters: 1) number of coronary arteries affected with atherosclerosis, 2) modified Gensa score, and 3) number of coronary arteries with stenosis > 50%. The severity of GD mucosal lesions was assessed by modified Lanza score, and Helicobacter pylori infection was confirmed by biopsy and pathohistological analysis of GD mucosa. Predictive value of different independent factors regarding the presence of GD mucosal lesions was assessed by multivariate analysis. RESULTS: The severity of CAD in patients with or without GD mucosal lesions did not differ by any of used scoring methods: 1) number of coronary arteries affected by atherosclerosis (2.15 +/- 0.85 vs. 2.00 +/- 0.87, p = 0.292), 2) modified Gensa score (71.22 +/- 51.78 vs. 69.89 +/- 54.18, p = 0.881), 3) number of coronary arteries with stenosis > 50% (3.89 +/- 2.05 vs. 3.47 +/- 2.25, p = 0.244). We also noticed that there had been no correlation between severity of CAD and severity of GD mucosal lesions. Correlation of number of coronary arteries affected with atherosclerosis with Lanza score resulted in r = 0.029, p = 0.721, correlation of Genza score with Lanza score resulted in r = 0.019, p = 0.082, and correlation of the number of coronary arteries with stenosis > 50% with Lanza score resulted in r = 0.079, p = 0.337. CONCLUSION: According to available method for evaluating the severity of CAD, in CAD patients ischemia has no or very minor role in pathogenesis of GD mucosa impairment.

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.