A quantitative evaluation of aerosol generation during cardiopulmonary resuscitation

It is unclear if cardiopulmonary resuscitation is an aerosol-generating procedure and whether this poses a risk of airborne disease transmission to healthcare workers and bystanders. Use of airborne transmission precautions during cardiopulmonary resuscitation may confer rescuer protection but risks patient harm due to delays in commencing treatment. To quantify the risk of respiratory aerosol generation during cardiopulmonary resuscitation in humans, we conducted an aerosol monitoring study during out-of-hospital cardiac arrests. Exhaled aerosol was recorded using an optical particle sizer spectrometer connected to the breathing system. Aerosol produced during resuscitation was compared with that produced by control participants under general anaesthesia ventilated with an equivalent respiratory pattern to cardiopulmonary resuscitation. A porcine cardiac arrest model was used to determine the independent contributions of ventilatory breaths, chest compressions and external cardiac defibrillation to aerosol generation. Time-series analysis of participants with cardiac arrest (n = 18) demonstrated a repeating waveform of respiratory aerosol that mapped to specific components of resuscitation. Very high peak aerosol concentrations were generated during ventilation of participants with cardiac arrest with median (IQR [range]) 17,926 (5546-59,209 [1523-242,648]) particles.l-1 , which were 24-fold greater than in control participants under general anaesthesia (744 (309-2106 [23-9099]) particles.l-1 , p < 0.001, n = 16). A substantial rise in aerosol also occurred with cardiac defibrillation and chest compressions. In a complimentary porcine model of cardiac arrest, aerosol recordings showed a strikingly similar profile to the human data. Time-averaged aerosol concentrations during ventilation were approximately 270-fold higher than before cardiac arrest (19,410 (2307-41,017 [104-136,025]) vs. 72 (41-136 [23-268]) particles.l-1 , p = 0.008). The porcine model also confirmed that both defibrillation and chest compressions generate high concentrations of aerosol independent of, but synergistic with, ventilation. In conclusion, multiple components of cardiopulmonary resuscitation generate high concentrations of respiratory aerosol. We recommend that airborne transmission precautions are warranted in the setting of high-risk pathogens, until the airway is secured with an airway device and breathing system with a filter.

Quantitative evaluation of coronary artery occlusion by 3D coronary volume reconstruction in a large animal model of acute myocardial infarction

Background

Large animal models of acute myocardial infarction (MI) offer an important platform to test novel therapies. Consistency of infarct size between animals is critical to ensure an accurate assessment of therapies against control. However, anatomical variation challenges the ability to achieve a consistent infarct size and care must be taken to respect the principles of the 3Rs through minimisation of interventional fatalities.

Purpose

To standardise the approach of a closed chest model of balloon occlusion-facilitated MI. Novel 3-dimensional quantitative coronary angiography (3DQCA) software has been used retrospectively to identify a correlation between coronary volume occlusion and the extension of the myocardial scar.

Methods

Twenty-four Yorkshire pigs (mean weight 63.1±3 kg) underwent a closed chest MI model via percutaneous occlusion of the mid portion of the left anterior descending artery (LAD) for 60 minutes. The evaluation of the myocardial damage was obtained via cardiac magnetic resonance imaging (CMR) between 24 and 48 hours after the MI model (Acute) and at 4–5 weeks after MI (Chronic). Troponin I was also measured at multiple timepoints. 3DQCA reconstruction (QAngio XA 3D, Medis medical imaging systems NL) was generated from 2 angiographic projections with segmental analysis of all 3 major epicardial vessels including lumen volume, reference diameters, and segment length. The occlusive volume and vessel length was identified through co-registration of balloon position.

Results

At the short term timepoint, a significant correlation was found between the LAD volume occluded and the scar size as percentage of the LV mass (Spearman correlation 0.72, p value &lt;0.01, Fig. 1). Using Youden index analysis we identified a cut-off point of 32.8% of the LAD volume to determine a scar volume &gt;20% (Fig. 2). At chronic phase the correlation between these two variables was not significant, although there was a trend towards significance (p value = 0.06, Cor = 0.54). No significant correlation was found with serum Troponin I.

Conclusions

There is a significant correlation between the LAD volume occluded and the overall scar size in the acute phase and at least 32.8% of the LAD volume should be occluded to determine a scar volume &gt;20% of the entire LV. This indicates that a prospective measure of occluded LAD volume might minimise the intra-experimental variability in studies aiming to reduce infarct size and acute myocardial injury.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): This research work was supported by grants awarded to Professor Ascione: the British Heart Foundation (BHF) (BHF IG/14/2/30991, BHF RM/13/2/30158), and the Medical Research Council (MRC) (MRC MR/L012723/1).

Impaired transcriptional compensation for oxidative damage in a porcine model of ischaemic cardiomyopathy

Background

The prognosis of heart failure remains poor. Energetic imbalances related to mitochondrial dysfunction, impaired oxidative phosphorylation and oxidative damage have been implicated in the pathogenesis or worsening of heart failure (1,2). Improved understanding of the metabolic alterations in heart failure may provide new biomarkers or therapeutic targets.

Purpose

We explored mutation rate, mitochondrial copy number and regional mitochondrial gene transcription in a porcine model of ischaemic cardiomyopathy. Specifically, we investigated the Dloop region – a promotor for mitochondrial DNA- in which mutations have been implicated in many cancers. We hypothesised that there may be differences in mutation rate and oxidative damage within the mitochondrial genome.

Methods

15 female Yorkshire pigs were studied. 7 animals underwent percutaneous balloon catheter myocardial infarction followed by termination at 4 weeks. A group of 8 healthy animals served as controls. Reverse transcription quantitative PCR (RT-qPCR) assays were performed to determine the gene expression levels of mitochondrial DNA codified genes (ND1, ND2, ND4, ATP6 and ND6). Quantitative PCR (qPCR) methodology was modified to obtain the relative mitochondrial copy number, mutation rate, and oxidative damage according to established methods (3–5).

Results

Significant mitochondrial transcriptional activity of the genes studied was seen in both groups (see Table 1 and 2). When examining the ND2-ND6 region (excluding the Dloop) in control animals, we note an inverse correlation with increased oxidative damage corresponding to a significantly lower mutation rate (p=0.017). There was no correlation between the mutation rate and oxidative damage in the ND6-ND2- including Dloop- region. However, when examining the Dloop specifically, there was a marked inverse correlation between oxidative damage and mutation rate (p=0.007). This suggests that in controls, there is regional variation in the susceptibility to damage within the mitochondrial genome which may trigger repair mechanisms. Indeed, the relative mitochondrial copy number was inversely associated to the mutation rate (p=0.08) in controls.

In contrast, in the chronic animals, we noted no correlation with the level of oxidative damage in the ND2-ND6, D-loop, or ND6–2 regions compared to mutation rate (p=0.52, p=0.53 and p=0.17 respectively). This indicates that there is a loss in the ability to instigate repair mechanisms in the setting of ischaemic cardiomyopathy.

Conclusions

This study demonstrates that in control animals, there appears to be regional variation in the ability to mitigate against mutations in response to oxidative damage within the mitochondrial genome. In contrast, this protection and/or the effectiveness of repair mechanisms appear to be impaired in the setting of ischaemic cardiomyopathy. This may be a driver, and in turn a therapeutic target, for adverse remodelling in this setting.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): This research work was supported by grants awarded to Professor Ascione: the British Heart Foundation (BHF) (BHF IG/14/2/30991, BHF RM/13/2/30158), and the Medical Research Council (MRC) (MRC MR/L012723/1).

Predictors of in-hospital mortality, 20-year survival and reflection on risk scoring in patients with impaired left ventricular function undergoing isolated coronary artery bypass grafting

Background

Impaired left ventricular ejection fraction (LVEF) is a risk factor for mortality in patients undergoing coronary artery bypass grafting (CABG). Limited data is available on survival after 5 years and sensitivity of preoperative risk scoring systems in this high-risk population.

Purpose

To investigate in-hospital mortality, 20-year survival, predictors of early and late mortality and sensitivity of available risk-scoring systems in a large population with moderate to poor baseline LVEF and undergoing isolated CABG.

Methods

Patients presenting with moderate to poor LVEF and undergoing isolated CABG between 1996 and 2015 were selected for the purpose of this study. LVEF was defined moderate if between 30–39% and poor if &lt;30%. Data collection was prospective and retrospectively analysed. Early and long-term mortality was derived from the NHS National Mortality Tracking system. Exclusion criteria included reoperations and combined procedures only. Patients undergoing urgent and emergency CABG procedures were included. Key outcome measures included 30-day health outcome, long-term survival, impact of incomplete revascularization (IC) and off-pump coronary artery bypass (OPCAB) surgery, independent predictors of poor in-hospital outcome and long-term mortality and reliability of Euroscore in predicting mortality in this high-risk population. Comparative analysis was conducted with Student t-test or Mann-whithney test fro numerical variable and Chi-Square for categorical variables. Survival were compared and reported using Log rank test and Kaplan Meier methods. A Cox Proportional Hazard model was developed to identify risk factors for long term mortality.

Results

5016 patients with reduced LVEF were identifiedL1024 (20.4%) with poor and 3992 (79.6%) with moderate LVEF. After excluding reoperations and combined procedures, the final sample consisted of 3867 patients. Average age was68 years, 83% were male, 40% had NYHA IV; 12.5% of patients received IC and 44% underwent OPCAB surgery. 30-day mortality was 4.4%, stroke 1.4% and renal failure requiring dialysis of 2.9%. Survival at 1, 5, 10 and 20 years was 91.1%, 76.7%, 55.1% and 22.1% respectively (Figure). OPCAB surgery was not associated with long-term mortality. Independent predictors of late mortality as shown in Table. Additive Euroscore and Logistic Euroscore appeared to overestimate mortality in this patient population (AUC 0.78).

Conclusions

In patients with reduced LVEF the use of CABG is associated with low rates of in-hospital mortality, key post-operative complications and excellent long-term survival. Incomplete revascularization but not OPCAB surgery are surgical predictors of long-term mortality. Euroscore appears to overestimate the risk of mortality in this population.

Funding Acknowledgement

Type of funding sources: None. Cox Hazard Ratio Table

Distinct metabolic transcriptional patterns and Warburg effect in porcine model of ischaemic cardiomyopathy

Background

Despite improvements in therapy for heart failure, the prognosis remains poor. Energetic imbalances related to mitochondrial dysfunction, impaired oxidative phosphorylation and oxidative damage have been implicated in the pathogenesis or worsening of heart failure. Improved understanding of the metabolic alterations of the heart may provide new biomarkers or therapeutic targets.

Purpose

It has been speculated that aerobic glycolysis, known as the Warburg effect, may be advantageous for cell survival whereby there is the opportunity for simultaneous energy production and production of intermediary metabolites crucial for anabolic pathways that sustain cell division and maintenance, and protein synthesis (1,2). In this study, we studied a preclinical model of ischaemic cardiomyopathy to investigate transcriptional patterns in two defined areas; peri-infarct and remote locations. Specifically, we investigated if aerobic glycolysis may be present in this setting.

Methods

18 female Yorkshire pigs were studied. 10 animals underwent balloon catheter myocardial infarction followed by termination at 4 weeks. A group of 8 healthy animals served as controls. All animals underwent cardiac MRI prior to termination confirming ventricular impairment and remodelling in the chronic animals (see Table 1). Gene expression profiles of glucose mobilisation and glucose metabolic markers (GLUT1, GLUT4, ANK2, GAPDH and LDHA), oxidative phosphorylation and mitochondrial function (ND1, TFAM, and PGC1-alpha), key markers of insulin resistance (AKT1, AS160) and a hypoxia marker (HIF1-alpha) were measured.

Results

Our results indicate the presence of two distinct metabolic profiles at the gene expression level, differing from control tissue but more interestingly with striking differences regionally. In the remote region compared to controls, we demonstrate a picture suggestive of increased glycolysis with significant transcriptional upregulation of GLUT1 and GLUT4 glucose transporters (p=0.01 and p=0.02 respectively), alongside a significant reduction in PGC1-alpha (p=0.04) with maintained transcriptional levels of LDHA and HIF1-alpha. Combined, these results are suggestive of reduced oxidative phosphorylation alongside compensated, or early stage, aerobic glycolytic metabolism in this region. In contrast, in peri-infarct tissue versus controls, we demonstrate a reduction in glycolysis (GLUT1 p=0.09, GLUT4 p=0.01 with a dramatic increase in GLUT1/GLUT4 ratio of 6.7 times) and reduced markers of mitochondrial function indicative of insulin-resistance with evidence of a fetal-pattern metabolic profile (see Table 2 for detailed results).

Conclusions

This study demonstrates distinct transcriptional profiles within hearts with ischaemic cardiomyopathy and for the first time suggests that the Warburg effect may be present in remote myocardium in this setting supporting the need for further work in this area.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): This research work was supported by grants awarded to Professor Ascione: the British Heart Foundation (BHF) (BHF IG/14/2/30991, BHF RM/13/2/30158), and the Medical Research Council (MRC) (MRC MR/L012723/1). Table 1. CMR parameters for animals studiedTable 2. Transcriptional signals

624 Twenty Years' Experience of Coronary Artery Bypass Grafting in Patients with Reduced Left Ventricular Ejection Fraction

Aim

Reduced Left Ventricular Ejection Fraction (LVEF) is a risk factor for patients undergoing Coronary Artery Bypass Grafting (CABG). The aim of our study was to compare short term outcomes and long-term (20 years) survival rates of patients with reduced LVEF undergoing CABG.

Method

Between 1996 and 2015, 5016 patients with reduced LVEF underwent CABG: 1024 (20.4%) had poor LVEF (&lt; 30%) and 3992 (79.6%) had moderate LVEF dysfunction (30-49%). After excluding reoperations and combined procedures, the final sample consisted of 3867 patients. Our primary outcomes were early in-hospital mortality and complications and long-term survivals.

Results

In-hospital mortality rate was 4.4%, stroke rate 1.4% and renal failure 2.9%. Survival rates at 1, 5, 10 and 20 years were 91.1%, 76.7%, 55.1% and 22.1% respectively. Additive Euroscore and Logistic Euroscore (AUC 0.78) is less reliable compared to normal LV patients. Complete revascularization was an independent factor affecting long term survival (HR: 0.85). No difference between OPCABG and ONCABG were found.

Conclusions

CABG is still safe and most likely the best treatment option for patients with reduced LVEF. Completeness of revascularization plays an important role in long term outcomes while OPCABG has no significant advantages. Euroscore has a reduced predicting ability in this group of patients.

Acute regional changes in myocardial strain may predict ventricular remodelling after myocardial infarction in a large animal model

To identify predictors of left ventricular remodelling (LVR) post-myocardial infarction (MI) and related molecular signatures, a porcine model of closed-chest balloon MI was used along with serial cardiac magnetic resonance imaging (CMRI) up to 5-6 weeks post-MI. Changes in myocardial strain and strain rates were derived from CMRI data. Tissue proteomics was compared between infarcted and non-infarcted territories. Peak values of left ventricular (LV) apical circumferential strain (ACS) changed over time together with peak global circumferential strain (GCS) while peak GLS epicardial strains or strain rates did not change over time. Early LVR post-MI enhanced abundance of 39 proteins in infarcted LV territories, 21 of which correlated with LV equatorial circumferential strain rate. The strongest associations were observed for D-3-phosphoglycerate dehydrogenase (D-3PGDH), cysteine and glycine-rich protein-2, and secreted frizzled-related protein 1 (sFRP1). This study shows that early changes in regional peak ACS persist at 5-6 weeks post-MI, when early LVR is observed along with increased tissue levels of D-3PGDH and sFRP1. More studies are needed to ascertain if the observed increase in tissue levels of D-3PGDH and sFRP1 might be casually involved in the pathogenesis of adverse LV remodelling.

P664 Relationship of left atrial function assessed by 2D speckle tracking echocardiography with left ventricular systolic function in patients with degenerative mitral regurgitation

Funding Acknowledgements

none

Background

In degenerative mitral regurgitation (DMR), left ventricle (LV) and left atrium (LA) undergo progressive volume overload leading to chamber remodelling and dysfunction in advanced stages. Speckle tracking echocardiography (STE) is an estabilished technique able in detecting subclinical LA and LV dysfunction in this setting. However data are lacking on the relationship of LA and LV function in DMR patients.

Purpose

Our aim was to assess LA function in patients with DMR and to explore its possible correlations with LV dimensions and systolic function.

Methods

We enrolled 95 patients with mild to severe DMR, dichotomizing them on the basis of mitral regurgitation severity (DMR 1-2: mild and mild-to-moderate MR; DMR 3-4: at least moderate to severe MR). LA function was assesed with 2D speckle tracking echocardiography.

Results

The two groups were well matched. DMR 3-4 group (n= 48) showed higher LA and LV volumes, lower right ventricle longitudinal systolic function and higher values of systolic pulmonary pressure. There was not significant difference in LV ejection fraction (LVEF) and global longitudinal strain (GLS). Among LA function indexes, only peak systolic reservoir strain was significantly reduced in DMR 3-4 group (21,9± 6,2% vs 24,7± 7,2% ; p= 0,04). Then population study was further divided in two groups according to the presence (LA dys+) or absence (LA dys-) of LA dysfunction, defined as reservoir strain values below the median [median 23.7%; LAdys- group (n. 49), LAdys+ group (n.46) ]. At the comparison of continuous variables (Tab.1), LAdys+ group showed larger LV end systolic diameter and more impaired LVEF (60,9± 9,8% vs 65,4± 4,8%; p: 0,004) and GLS (20,04 ± 3,7% vs 23,53 ± 2,7%; p &lt;0,001).

Conclusions

Our data showed that LA reservoir strain was impaired in patients with moderate to severe DMR. Furthermore, patients with LA dysfunction showed reduced LVEF and GLS values. Consequently, LA dysfunction assessed with STE may be a novel marker of early LV systolic dysfunction in patients with degenerative mitral regurgitation.

Tab.1 LAdysf- (n = 49) LAdysf+ (n = 46) P value LVESD (mm) 31.78 ± 4.1 34.74 ± 7.6 0.020 LAVI (mL/mq) 44.5 ± 15.1 55.6 ± 25.6 0.015 TAPSE (mm) 26.30 ± 3.96 24.02 ± 3.31 0.004 sPAP (mmHg) 31.4 ± 7.0 36.4 ± 10.9 0.009 LVEF (%) 65.4 ± 4.8 60.9 ± 9.8 0.004 GLS (%) 23.5 ± 2.7 20.0 ± 3.7 &lt;0.001 Comparison of continuous variables between patients with and without LA dysfunction.

Inflammation, oxidative stress and postoperative atrial fibrillation in cardiac surgery

Postoperative atrial fibrillation (POAF) is a common complication of cardiac surgery that occurs in up to 60% of patients. POAF is associated with increased risk of cardiovascular mortality, stroke and other arrhythmias that can impact on early and long term clinical outcomes and health economics. Many factors such as disease-induced cardiac remodelling, operative trauma, changes in atrial pressure and chemical stimulation and reflex sympathetic/parasympathetic activation have been implicated in the development of POAF. There is mounting evidence to support a major role for inflammation and oxidative stress in the pathogenesis of POAF. Both are consequences of using cardiopulmonary bypass and reperfusion following ischaemic cardioplegic arrest. Subsequently, several anti-inflammatory and antioxidant drugs have been tested in an attempt to reduce the incidence of POAF. However, prevention remains suboptimal and thus far none of the tested drugs has provided sufficient efficacy to be widely introduced in clinical practice. A better understanding of the cellular and molecular mechanisms responsible for the onset and persistence of POAF is needed to develop more effective prediction and interventions.

Expression of ets family genes in hematopoietic-cells

We have examined the expression of the ets family of transcription factors in different types of hematopoietic cells. Our results demonstrate that several members of the ets gene family are expressed differentially in hematopoietic cells. During phorbol ester induced differentiation of HL60 cells, ETS2, PEA3, as well as GABPalpha and GABPbeta mRNAs are coordinately induced. During the activation of T-cells, ETS2 proteins are induced; however, the expression of the ETS1 and ERGB gene products are reduced. These results demonstrate that the regulation of ets family of genes is complex and depends on cell type. This observation leads to the conclusion that the regulation of ets target genes, will be dependent, in part, upon the type of ets genes expressed in each particular cell type.

Influence of nucleotides flanking the ggaa core sequence on ets1 and ets2 DNA-binding activity and the mechanism of ets1 autoregulation

The Ets family of genes encode nuclear proteins that activate transcription by binding to a specific purine-rich (GGAA) ets binding sequence (EBS) present in promoters/enhancers of various genes. We have previously shown that over-expression of ets1 via transfection of ets1 expression vectors into NIH3T3 cells induced the expression of the endogenous Ets1 gene. Here we report that the autoregulation occurs as a result of the ets1 protein binding to the EBS-core located in its own promoter. In the present study, we have also identified Ets binding sites in the IL-4, G-CSF (granulocyte colony stimulating factor), and the 2'5' OAS (oligoadenylate synthetase) promoters by binding with Ets1 and Ets2 proteins using electrophoretic mobility shift assays. Interestingly, we have found that the EBS containing T nucleotides on either side of the GGAA core sequence, does not bind Ets1 or Ets2 proteins. Our findings demonstrate that the sequences surrounding the purine core - GGAA- have a profound influence on the binding of Ets proteins.

The competent isolated double orifice mitral valve: an incidental finding during excision of a papillary fibroelastoma

The double orifice mitral valve is associated with a number of congenital abnormalities and comprises two mitral orifices separated by an accessory bridge of fibrous tissue and surrounded by a single fibrous annulus. We present our management of a case of a double orifice mitral valve associated with a papillary fibroelastoma.

Body dissatisfaction, abnormal eating behaviours and eating disorder attitude in homo- and heterosexuals

OBJECTIVE

The primary aim of this study was to investigate the relationship between sexual orientation and disordered eating attitudes and behaviours in a sample of homosexuals and heterosexuals subject.

METHODS

We screened 110 homosexuals (85 males and 25 females) and 121 heterosexuals (85 males and 36 females) by means of: a) an ad hoc socio-demographic schedule; b) the Eating Disorders Inventory 2 (EDI 2); the Eating Disorders Inventory 2 - Symptom Checklist (EDI-SC); the Body Uneasiness Test (BUT).

RESULTS

Male homosexuals obtained much higher scores than male heterosexuals on the EDI 2 Drive for thinness, Bulimia, Ineffectiveness, Interoceptive awareness, Impulse regulation scales and on all the BUT subscales. Similarly, with regard to eating behaviours, a significantly higher frequency in the use of strategies to compensate weight increase was observed. On all these scales the sample of homosexual males did not show any significant differences from the group of hetero- and homosexual women. The male homosexuals who claimed they were not in a stable relationship scored higher in all the variables considered.

DISCUSSION

Our findings seem to suggest that homosexual orientation is associated with greater body dissatisfaction and abnormal eating behaviours in males, in particular among those who claimed they were not in a sentimental relationship.

Laboratory culturing of a thermophilic alga at high temperature

Conditions for laboratory growth of the thermophilic alga Cyanidium caldarium at elevated temperatures have been developed. Growth characteristics of the organisms are described.

The importance of myocardial amino acids during ischemia and reperfusion in dilated left ventricle of patients with degenerative mitral valve disease

Taurine, glutamine, glutamate, aspartate, and alanine are the most abundant intracellular free amino acids in human heart. The myocardial concentration of these amino acids changes during ischemia and reperfusion due to alterations in metabolic and ionic homeostasis. We hypothesized that dilated left ventricle secondary to mitral valve disease has different levels of amino acids compared to the right ventricle and that such differences determine the extent of amino acids' changes during ischemia and reperfusion. Myocardial concentration of amino acids was measured in biopsies collected from left and right ventricles before cardioplegic arrest (Custodiol HTK) and 10 min after reperfusion in patients undergoing mitral valve surgery. The dilated left ventricle had markedly higher (P < 0.05) concentrations (nmol/mg wet weight) of taurine (17.0 +/- 1.5 vs. 10.9 +/- 1.5), glutamine (20.5 +/- 2.4 vs. 12.1 +/- 1.2), and glutamate (18.3 +/- 2.2 vs. 11.4 +/- 1.5) when compared to right ventricle. There were no differences in the basal levels of alanine or aspartate. Upon reperfusion, a significant (P < 0.05) fall in taurine and glutamine was seen only in the left ventricle. These changes are likely to be due to transport (taurine) and/or metabolism (glutamine). There was a marked increase in the alanine to glutamate ratio in both ventricles indicative of ischemic stress which was confirmed by global release of lactate during reperfusion. This study shows that in contrast to the right ventricle, the dilated left ventricle had remodeled to accumulate amino acids which are used during ischemia and reperfusion. Whether these changes reflect differences in degree of cardioplegic protection between the two ventricles remain to be investigated.

Inadequate blood glucose control is associated with in-hospital mortality and morbidity in diabetic and nondiabetic patients undergoing cardiac surgery

BACKGROUND

Derangement of glucose metabolism after surgery is not specific to patients with diabetes mellitus. We investigated the effect of different degrees of blood glucose control (BGC) on clinical outcomes after cardiac surgery.

METHODS AND RESULTS

We analyzed 8727 adults operated on between April 1996 and March 2004. The highest blood glucose level recorded over the first 60 hours postoperatively was used to classify patients as having good (<200 mg/dL), moderate (200 to 250 mg/dL), or poor (>250 mg/dL) BGC; 7547 patients (85%) had good, 905 (10%) had moderate, and 365 (4%) had poor BGC. Patients with inadequate BGC were more likely to present with advanced New York Heart Association class, congestive heart failure, hypertension, renal dysfunction, and ejection fraction <50% (P0<or=.001). We found that 52% of patients with poor, 31% with moderate, and 8% with good BGC had diabetes mellitus. Inadequate BGC, but not diabetes mellitus (P=0.79), was associated with in-hospital mortality (good, 1.8%; moderate, 4.2%; poor, 9.6%; adjusted odds ratio: poor versus good BGC, 3.90 [95% confidence interval, 2.47 to 6.15]; moderate versus good BGC, 1.68 [95% confidence interval, 1.25 to 2.25]). Inadequate BGC also was associated with postoperative myocardial infarction (eg, odds ratio, poor versus good BGC: 2.73 [95% confidence interval, 1.74 to 4.26]) and with pulmonary and renal complications in patients without known diabetes mellitus (eg, odds ratio, poor versus good BGC: 2.27 [95% confidence interval, 1.65 to 3.12] and 2.82 [95% confidence interval, 1.54 to 5.14] respectively).

CONCLUSIONS

More than 50% of patients with moderate to poor BGC after cardiac surgery were not previously identified as diabetic. Inadequate postoperative BGC is a predictor of in-hospital mortality and morbidity.

Risk factors for and economic implications of prolonged ventilation after cardiac surgery

OBJECTIVE

The study's objective was to identify predictors of prolonged ventilation and assess clinical and cost implications in patients undergoing cardiac surgery.

METHODS

Patients undergoing cardiac surgery were classified as (1) ventilated less than 96 hours or (2) ventilated 96 hours or more. Multivariate modeling was used to identify predictors of prolonged ventilation and to ascertain the impact of prolonged ventilation on in-hospital mortality and bed occupancy costs and 5-year survival.

RESULTS

A total of 7553 patients were studied; 197 (2.6%) had prolonged ventilation. Median ventilation times were 8 and 192 hours, and in-hospital mortality was 1.0% and 22.2% in the control and prolonged ventilation groups, respectively (P < .001). In-hospital mortality remained higher in the prolonged ventilation group after adjustment and when comparing propensity-matched patients (odds ratio 8.06; 95% confidence interval [CI] 4.27-15.2; P < .001 for propensity-matched groups). Independent predictors of prolonged ventilation were as follows: older age, New York Heart Association class, ejection fraction less than 50%, creatinine greater than 200 micromol/L, multiple valve replacements, aortic procedures, operative priority, reoperation for bleeding, inotropes, and preoperative intra-aortic balloon pump. Five-year survival was lower in the prolonged ventilation group (56.1% [95% CI 46.6%-64.6%] vs 88.8% [95% CI 87.9%-89.6%]) also after adjustment for imbalances and when comparing propensity-matched patients (hazard ratio 2.39; 95% CI 1.75-3.27; P < .001 for propensity-matched groups). Mean bed occupancy costs were 14,286 dollars (95% CI 12,731 dollars-15,690 dollars) and 2761 dollars (95% CI 2705 dollars-2814 dollars) in the prolonged ventilation and control groups, respectively (P < .001).

CONCLUSION

Prolonged ventilation is associated with high in-hospital mortality and costs, and poor 5-year survival. Identified predictors of prolonged ventilation might help to optimize the clinical management of these patients.

ETS transcription factors and targets in tumour invasion, angiogenesis and bone metastasis

The ETS gene family encodes unique transcription regulators that have a common ETS DNA binding domain. At least 25 distinct ETS related genes have been isolated from various species. The ETS family transcription factors are known to regulate genetic programs essential for differentiation and development processes and play diverse roles in a number of biological processes such as organogenesis and tissue remodelling during murine development, hematopoiesis, B-cell development, activation of T-cells and signal transduction, as well as osteogenesis, osteoblast differentiation and extracellular matrix mineralization. Based on the observation of overexpression of ETS related genes in various primary and metastatic tumors, their utility as potential therapeutic targets has been suggested. Antisense oligonucleotides, transdominant, and dominant-negative mutants have been exploited to target and inhibit ETS gene expression selectively. These ETS-targeted studies are being pursued to assess their antitumour effect, and hold the potential that such specific ETS-targeted inhibitors may become a viable option for cancer therapy. Collectively, these studies also demonstrate that Ets factors can regulate multiple aspects of the malignant phenotype of many tumor cells in particular neoangiogenesis and extracellular matrix-regulated (ECM-regulated) cell proliferation, motility and invasiveness.

Operative factors that contribute to post-operative atrial fibrillation: insights from a prospective randomized trial

Atrial fibrillation (AF) is the most common complication following cardiac surgery and is associated with significant increases in postoperative morbidity, length of stay and cost of care. In a randomized study we assessed the impact of coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB) (off-pump, n = 100), compared to conventional (on-pump, n = 100) CABG, on the frequency of postoperative AF. Arrhythmias were detected using an automated arrhythmia detector for the first 72 hours following surgery and by four hourly clinical observations thereafter. AF was defined as an irregular narrow complex rhythm (in the absence of bundle branch block) with absence of discrete P waves lasting greater then 10 minutes. There was a significant reduction in the incidence of postoperative AF in the off-pump group (11% versus 45%, P < 0.001) in addition to significant reductions in blood usage, postoperative pneumonia, inotrope requirements, and hospital and intensive care unit stay. Univariate analysis identified all these variables as risk factors for AF, however multivariate regression analysis identified CPB and cardioplegic arrest as the only independent predictor of postoperative AF (OR 7.4; 95% CI 3.4 to 17.9). This study therefore suggests that the inflammatory response to bypass, myocardial ischaemia and atrial cannulation are significant contributory factors to the development of AF following cardiac surgery. In the light of more recent trials it is apparent that this benefit may be most marked in patients with multiple perioperative risk factors for postoperative AF.

Socioeconomic deprivation is a predictor of poor postoperative cardiovascular outcomes in patients undergoing coronary artery bypass grafting

OBJECTIVE

To investigate the effects of socioeconomic deprivation on cardiovascular risk factors and postoperative clinical outcomes of patients undergoing coronary artery bypass grafting (CABG).

DESIGN

Retrospective analysis of prospectively collected data.

SETTING

Surgical population of the southwest of England, April 1996 and August 2000.

STUDY GROUP

Data on 3578 consecutive patients undergoing CABG at the Bristol Royal Infirmary NHS Trust were abstracted. Data were retrieved from the Patient Analysis & Tracking System. Carstairs index was used to measure socioeconomic deprivation of area of residence and was divided into five quintiles, where quintile 1 denotes least deprived and 5 most deprived.

OUTCOME MEASURES

End points were postoperative complications and 30 day mortality.

RESULTS

Higher deprivation scores were associated with younger age (p < 0.004), greater body mass index, diabetes, smoking at time of surgery, and higher EuroSCOREs (all p < or = 0.001). After adjustment for EuroSCORE, socioeconomic deprivation was independently associated with postoperative myocardial infarction (p = 0.05) and combined postoperative myocardial infarction, stroke, and death (p = 0.016). Hospital length of stay for the patients in the highest quintiles was also significantly longer than for those in the lower quintiles (p = 0.04).

CONCLUSION

Patients undergoing CABG living in areas with high deprivation scores are younger, have more clinical risk factors, and experience more postoperative cardiovascular complications than patients living in low deprivation score areas.

Coronary artery bypass grafting in patients over 70 years old: the influence of age and surgical technique on early and mid-term clinical outcomes

OBJECTIVE

To investigate the influence of age and modern techniques of coronary artery bypass grafting with or without cardiopulmonary bypass on early and mid-term mortality and morbidity in a consecutive series of elderly patients.

METHODS

From April 1996 to December 2000, data of 3842 patients undergoing coronary revascularisation were prospectively entered into a database. Data were extracted for 990 patients older than 70 years: (A) 70-74 years, (n=659); (B) 75 or more years, (n=331).

RESULTS

A total of 990 elderly patients (> or = 70 years) underwent coronary revascularisation, 219 (22.1%) with off-pump surgery. Elderly patients were more likely to have higher CCS, NYHA and EuroScores, history of previous MI, unstable angina, renal dysfunction, left main stem disease > or = 50%, and to be urgent. However, they were less likely to be overweight. In-hospital mortality, occurrence of re-intubation, renal dysfunction, and hospital stay were significantly higher in this elderly group. Overall, the distribution of mortality was doubled in the female gender although this was not statistically significant. Patients undergoing on-pump surgery had lower EuroScore, were less likely to be >75 years of age, likely to have obesity or hypercholesterolaemia, or to have suffered a previous cerebro-vascular accident. However, they had more extensive coronary disease, were more likely to have unstable angina, and received more grafts than those undergoing off-pump surgery. After adjustment for prognostic variables, off-pump surgery was found to be associated with reduced inotropic use, intra-operative arrhythmias, blood loss and transfusion requirement when compared to on-pump coronary surgery (point estimates of odd ratios, 0.26-0.87) (all P<0.05). Mid-term mortality or cardiac-related events were similar in the two groups.

CONCLUSIONS

Early but not mid-term mortality is higher in patients aged 75 or more years when compared with those aged 70-74 years. Off-pump coronary artery bypass surgery is safe and effective in the elderly population.

Detection of postoperative pseudoaneurysms following abdominal aortic aneurysm repair in Behçet's disease by MRA

We report the development of two anastomotic pseudoaneurysms in a patient with Behçet's disease eighteen months after abdominal aortic aneurysm repair. Major asymptomatic vascular complications should be suspected in patients with Behçet's disease with a history of vascular surgery and treated expediently due to the risk of rupture. Magnetic resonance angiography, contrast-enhanced computed tomography or ultrasound scanning should be performed at least every 6 months after vascular surgery.

Myocardial injury in hypertrophic hearts of patients undergoing aortic valve surgery using cold or warm blood cardioplegia

OBJECTIVES

Myocardial protection techniques during cardiac surgery have been largely investigated in the clinical setting of coronary revascularisation. Few studies have been carried out on patients with left ventricular hypertrophy where the choice of delivery, and temperature of cardioplegia remain controversial. This study investigates metabolic changes and myocardial injury in hypertrophic hearts of patients undergoing aortic valve surgery using antegrade cold or warm blood cardioplegia.

METHODS

Thirty-five patients were prospectively randomised to intermittent antegrade cold or warm blood cardioplegia. Left ventricular biopsies were collected at 5min following institution of cardiopulmonary bypass, 30min after cross-clamping the aorta and 20min after cross-clamp removal, and used to determine metabolic changes during surgery. Metabolites (adenine nucleotides, amino acids and lactate) were measured using high pressure liquid chromatography and enzymatic techniques. Postoperative myocardial troponin I release was used as a marker of myocardial injury.

RESULTS

Ischaemic arrest was associated with significant increase in lactate and alanine/glutamate ratio only in the warm blood group. During reperfusion, alanine/glutamate ratio was higher than preischaemic levels in both groups, but the extent of the increase was considerably greater in the warm blood group. Troponin I release was markedly (P<0.05, Mean+/-SD) lower at 1, 24 and 48h postoperatively in the cold compared to the warm blood group (0.51+/-0.37, 0.37+/-0.22 and 0.27+/-0.19 vs. 0.75+/-0.42, 0.73+/-0.51 and 0.54+/-0.38ng/ml for cold vs. warm group, respectively).

CONCLUSIONS

Cold blood cardioplegia is associated with less ischaemic stress and myocardial injury compared to warm blood cardioplegia in patients with aortic stenosis undergoing valve replacement surgery. Both cardioplegic techniques, however, confer sub-optimal myocardial protection.

Coronary revascularization with or without cardiopulmonary bypass in patients with preoperative nondialysis-dependent renal insufficiency

BACKGROUND

Preoperative renal insufficiency is a predictor of acute renal failure in patients undergoing conventional coronary artery bypass grafting. Off-pump coronary artery bypass operations have been shown to reduce renal dysfunction in patients with normal renal function, but the effect of this technique in patients with preoperative nondialysis-dependent renal insufficiency is unknown.

METHODS

From June 1996 to December 1999, data of 3,250 consecutive patients undergoing coronary artery bypass grafting were prospectively entered into the Patient Analysis & Tracking Systems (PATS, Dendrite Clinical Systems, London, UK). Two hundred and fifty-three patients with preoperative serum creatinine more than 150 micromol/L were identified (202 patients on-pump, 51 patients off-pump), and clinical outcomes were analyzed. Serum creatinine and urea, in-hospital mortality, and morbidity were compared between groups. The association of perioperative factors with acute renal failure was investigated by multiple logistic regression analysis.

RESULTS

Preoperative characteristics were similar between the groups. Mean number of grafts was 2.9 +/- 0.8 and 2.3 +/- 0.8 in the on-pump and off-pump groups, respectively (p < 0.0001). Comparison between groups showed a significantly higher incidence of stroke, inotropic requirement, blood loss, and transfusion of red packed cell and platelets in the on-pump group (all p < 0.05). Postoperative serum creatinine and urea were higher in the on-pump group with a significant difference at 12 hours postoperatively (p < 0.05). Logistic regression analysis identified cardiopulmonary bypass, serum creatinine level 60 hours postoperatively, inotropic requirement, need for intraaortic balloon pump, transfusion of red packed cell, and hours of ventilation as predictors of postoperative acute renal failure.

CONCLUSIONS

This study suggests that off-pump coronary artery bypass operations reduce in-hospital morbidity and the likelihood of acute renal failure in patients with preoperative nondialysis-dependent renal insufficiency undergoing myocardial revascularization.

One-stage coronary and abdominal aortic operation with or without cardiopulmonary bypass: early and midterm follow-up

BACKGROUND

The aim of this study was to compare hospital, early, and late clinical outcomes for patients undergoing one-stage, coronary and abdominal aortic surgical intervention with and without cardiopulmonary bypass.

METHODS

From March 1990 to September 1999, 42 consecutive patients underwent combined operations at a single institution. Cardiopulmonary bypass and cardioplegic arrest were used during coronary revascularization in the first 20 patients (on-pump group), and the next 22 patients received the one-stage operations on the beating heart (off-pump group).

RESULTS

Baseline characteristics were similar between groups. Three cardiac-related hospital deaths occurred in the on-pump group and one such death in the off-pump group (p = 0.25). Cardiac-related events, pulmonary complications, inotropic support, blood loss and transfusion requirements, intensive care unit stay, and hospital stay were significantly reduced in the off-pump group (all, p < 0.05). The actuarial survival rates in the on-pump and off-pump groups were 80% and 95%, respectively, at 1 year (p = 0.13) and 75% and 89%, respectively, at 3 years (p = 0.22). Freedom from cardiac-related events at 1-year follow-up was 91% in the off-pump group and 65% in the on-pump group (p < 0.05). No difference in cardiac-related events between groups was observed at 3 years.

CONCLUSIONS

Off-pump coronary surgical procedures decrease postoperative complications in high-risk patients undergoing simultaneous coronary and abdominal aortic operations compared with the conventional one-stage procedure. The early benefits achieved with off-pump surgical intervention are not at the expense of the long-term clinical outcome.

Clinical and angiographic outcome of different surgical strategies of bilateral internal mammary artery grafting

Long-term survival, relief of angina, and prevention of myocardial infarction after coronary revascularization are related to the preoperative status of the patient, progression of coronary artery atherosclerosis, and the patency of the conduits used. The increased use of the internal mammary artery for coronary grafting depends upon the accumulation of data on superior late patency compared with venous conduits. These data have supported the simultaneous use of both left and right internal mammary arteries with reported improved late survival. However, controversy still surrounds the clinical and angiographic outcomes of some of the surgical strategies of bilateral internal mammary artery grafting. This review examines a range of surgical strategies of bilateral internal mammary artery grafting and their mid- and long-term clinical and angiographic outcomes. From the available data, careful preoperative selection of patients is paramount. Clinical and angiographic outcome of bilateral internal mammary grafting is superior to single internal mammary grafting with supplemental vein grafts when pedicled, sequential, or free aorto-coronary internal mammary artery is used. Further studies are needed to evaluate the midterm and long-term clinical and angiographic outcomes of complex strategies such as Y or T procedures.

Reduced postoperative blood loss and transfusion requirement after beating-heart coronary operations: a prospective randomized study

OBJECTIVE

Coronary artery bypass grafting on the beating heart through median sternotomy is a relatively new treatment, which allows multiple revascularization without the use of cardiopulmonary bypass. A prospective randomized study was designed to investigate the effect of coronary bypass with or without cardiopulmonary bypass on postoperative blood loss and transfusion requirement.

METHODS

Two hundred patients with coronary artery disease were prospectively randomized to (1) on-pump treatment with conventional cardiopulmonary bypass and cardioplegic arrest and (2) off-pump treatment on the beating heart. Postoperative blood loss identified as total chest tube drainage, transfusion requirement, and related costs together with hematologic indices and clotting profiles were analyzed.

RESULTS

There was no difference between the groups with respect to preoperative and intraoperative patient variables. The mean ratio of postoperative blood loss and 95% confidence interval between groups was 1.64 and 1.39 to 1.94, respectively, suggesting on average a postoperative blood loss 1.6 times higher in the on-pump group compared with the off-pump group. Seventy-seven patients in the off-pump group required no blood transfusion compared with only 48 in the on-pump group (P <.01). Furthermore, less than 5% of patients in the on-pump group required fresh frozen plasma and platelet transfusion compared with 30% and 25%, respectively, in the on-pump group (both P <.05). Mean transfusion cost per patient was higher in the on-pump compared with that in the off-pump group ($184.8 +/- $35.2 vs $21.47 +/- $6.9, P <.01).

CONCLUSIONS

Coronary artery bypass grafting on the beating heart is associated with a significant reduction in postoperative blood loss, transfusion requirement, and transfusion-related cost when compared with conventional revascularization with cardiopulmonary bypass and cardioplegic arrest.

Off-pump coronary artery bypass surgery for critical left main stem disease: safety, efficacy and outcome

OBJECTIVES

To determine whether patients with critical left main stem (LMS) coronary artery disease can undergo off-pump coronary artery bypass (OPCAB) surgery safely and successfully.

METHODS

From May 1996 to March 2000 data for patients with critical (> or =50%) LMS stenosis who underwent conventional coronary artery bypass surgery with cardiopulmonary bypass (CCAB) or without (OPCAB) were collected prospectively using the Patient Analysis & Tracking System. A reusable pressure stabilizer, intra-coronary shunts and a single posterior pericardial stitch exposure technique were used in all OPCAB cases. Non-randomized, retrospective data analysis included demographic and preoperative risk factors, operative details, clinical outcome and early follow-up.

RESULTS

During the study period 387 patients with LMS stenosis underwent surgery (OPCAB n=75, CCAB n=312). Groups were similar in terms of preoperative and intraoperative variables although CCAB patients received significantly more grafts per patient (3.1+/-0.73 vs. 2.6+/-0.76, P< or =0.001). Mortality was similar in both groups (OPCAB 1.3% vs. CCAB 2.6%). OPCAB patients when compared to CCAB patients had a lower requirement for postoperative inotropes (12.0% vs. 38.1%, P=0.0001), temporary postoperative pacing (2.7% vs. 10.1%, P=0.02), and blood product transfusion (6.7% vs. 31.4%, P<0.0001), a lower incidence of postoperative chest infection (0% vs. 6.7%, P=0.02) and a slightly reduced postoperative length of stay (7.9+/-5.46 vs. 8.3+/-5.11 days, P=0.01). At 24 months follow-up, CCAB and OPCAB actuarial survival was 94.1+/-1.7% and 97.7+/-2.3%, respectively.

CONCLUSIONS

OPCAB surgery is safe and effective in patients with critical LMS disease.

Haemodynamic changes during beating heart coronary surgery with the 'Bristol Technique'

OBJECTIVES

Optimal exposure and stabilization of the target coronary vessel is essential to allow the construction of a precise coronary anastomosis during off pump coronary surgery. However, this might be achieved at the expense of significant haemodynamic deterioration, particularly while grafting the circumflex and the posterior descending coronary arteries. The present study was designed to assess the haemodynamic changes with the beating heart positioned for grafting the three main coronaries.

METHODS

Twenty-nine consecutive patients (21 male, mean age 62.6+/-7.1 years) undergoing off pump coronary surgery were enrolled in the study. Three different surgical settings of exposure and stabilization were used according to the site of anastomosis: left anterior descending (LAD - set-up 1; n=29), posterior descending (PDA - set-up 2; n=15), and circumflex (Cx - set-up 3; n=21) coronary arteries. Haemodynamic measurements were recorded before any cardiac manipulation (baseline) in set-ups 1, 2 and 3, and immediately after the completion of each distal anastomosis with the heart returned to its anatomical position.

RESULTS

There were no marked changes in heart rate (HR) and systemic mean arterial pressure during the construction of the anastomoses for any of the three surgical settings. Set-up 1 (LAD) showed a decrease of 15.5% in stroke volume (SV) and an increase of 9% in pulmonary capillary wedge pressure (PCWP) compared to baseline (both P<0.05), with all the other haemodynamic parameters remaining unchanged. Set-up 2 (PDA) showed a marked decrease in SV and cardiac index (CI), and an increase in central venous pressure (CVP) when compared to baseline (all P<0.05). The most extensive changes were observed in set-up 3 (Cx) with a considerable reduction in SV and CI, and an increase in CVP, PCWP, pulmonary arterial pressure, and systemic vascular resistance index (all P<0.05). These haemodynamic changes were transient and totally recovered after the heart was returned to its anatomical position.

CONCLUSIONS

Exposure and stabilization of the three main coronary arteries during beating heart surgery does not produce any appreciable change in systemic blood pressure and HR. The haemodynamic deterioration observed during the construction of the circumflex and posterior descending coronary arteries distal anastomoses is transient and well tolerated with no adverse clinical events.

Predictors of atrial fibrillation after conventional and beating heart coronary surgery: A prospective, randomized study

BACKGROUND

Atrial fibrillation (AF) increases the morbidity of CABG. The pathophysiology is uncertain, and its prevention remains suboptimal. This prospective, randomized study was designed to define the role of cardiopulmonary bypass (CPB) and cardioplegic arrest in the pathogenesis of this complication.

METHODS AND RESULTS

Two hundred patients were prospectively randomized to (1) on-pump conventional surgery [(100 patients, 79 men, mean age 63 (40 to 77) years)] with normothermic CPB and cardioplegic arrest of the heart or (2) off-pump surgery [(100 patients, 82 men, mean age 63 (38 to 86) years)] on the beating heart. Heart rate and rhythm were continuously monitored with an automated arrhythmia detector during the first 72 hours after surgery. Thereafter, routine clinical observation was performed and continuous monitoring restarted in the case of arrhythmia. The association of perioperative factors with AF was investigated by univariate analysis. Significant variables were then included into a stepwise logistic regression model to ascertain their independent influence on the occurrence of AF. There were no significant baseline differences between groups. Thirty-nine patients in the on-pump group and 8 patients in the off-pump group had postoperative sustained AF (P:=0.001). Univariate analysis showed that CPB inclusive of cardioplegic arrest, postoperative inotropic support, intubation time, chest infection, and hospital length of stay were predictors of AF (all P:<0.05). However, stepwise multivariate regression analysis identified CPB inclusive of cardioplegic arrest as the only independent predictor of postoperative AF (OR 7.4; CI 3.4 to 17.9).

CONCLUSIONS

CPB inclusive of cardioplegic arrest is the main independent predictor of postoperative AF in patients undergoing coronary revascularization.

Inflammatory response after coronary revascularization with or without cardiopulmonary bypass

BACKGROUND

We sought to investigate the effect of multiple coronary artery bypass grafting (CABG) with or without cardiopulmonary bypass (CPB) on the perioperative inflammatory response.

METHODS

Sixty patients undergoing CABG were randomly assigned to one of two groups: (A) on pump with conventional CPB and cardioplegic arrest, and (B) off pump on the beating heart. Serum samples were collected for estimation of neutrophil elastase, interleukin 8 (IL-8), C3a, and C5a preoperatively and at 1, 4, 12, and 24 hours postoperatively. Furthermore, white blood cell (WBC), neutrophil, and monocyte counts were carried out preoperatively and at 1, 12, 36 and 60 hours postoperatively. Overall incidence of infection and perioperative clinical outcome were also recorded.

RESULTS

The groups were similar in terms of age, weight, gender ratio, extent of coronary disease, left ventricular function, and number of grafts per patient. Neutrophil elastase concentration peaked early after CPB in the on-pump group, with a decline with time. Repeated-measures analysis of variance between groups and comparisons at each time point (modified Bonferroni) showed elastase concentrations were significantly higher in the on-pump than the off-pump group (both p < 0.0001). IL-8 increased significantly after surgery in the on-pump group, with no decline during the observation period (p = 0.01 vs off pump). C3a and C5a rose early after surgery in both groups when compared with baseline values. Postoperative WBC, neutrophil, and monocyte counts were significantly higher in the on-pump than the off-pump group (p < 0.01). Finally, the incidence of postoperative overall infections was significantly higher in the on-pump group (p < 0.0001 vs off pump).

CONCLUSIONS

CABG on the beating heart is associated with a significant reduction in inflammatory response and postoperative infection when compared with conventional revascularization with CPB and cardioplegic arrest.

Emergency repair of type A aortic dissection in type IV Ehlers-Danlos syndrome

Ehlers-Danlos syndrome type IV is a distinctive syndrome in which thin and fragile skin, premature ageing, bruising and scarring are combined with lethal or life-threatening arterial weakness. Aortic rupture either at the aortic root and arch, or sometimes lower down the artery, are particularly characteristic. Even quite minor injury can produce dangerous vascular tearing and damage. Technical difficulties encountered in arterial repair or venous ligature are particularly worrying. The authors report the treatment of a ruptured type A aortic dissection associated with Ehlers-Danlos syndrome where the extreme fragility of the tissues and tendency to bleed posed a difficult task for the surgeon.

Combined coronary artery and abdominal aortic surgery without cardiopulmonary bypass

To determine the effects of beating heart surgery on patients undergoing simultaneous coronary artery bypass grafting and abdominal aortic surgery, we performed such surgery on 20 patients (mean age, 64.55+/-796 SD years). Abdominal aortic disease was defined as an abdominal aortic aneurysm larger than 5 cm in diameter or as end-stage aortic occlusive disease. Hemodynamic measurements, inotropic requirements, and incidence of perioperative myocardial infarction and arrhythmias were recorded, as were subsystem clinical outcomes, length of intensive care unit and hospital stays, blood loss, and transfusion requirements. There was no incidence of death, perioperative myocardial infarction, stroke, or acute renal failure. The mean number of grafts per patient was 1.95+/-0.69. Only 4 minor postoperative complications were observed: three patients (15%) had evidence of supraventricular tachyarrhythmias, and 1 patient (5%) had chest infection that required a longer-than-average intubation period. Six patients (30%) required minimal-to-moderate inotropic support. The mean blood loss was 673+/-246.8 mL and transfusion requirements were low. The mean intensive care unit and hospital lengths of stay were 2. 12+/-0.33 days and 708+/-1.44 days, respectively. Clinical follow-up (mean, 10 months) showed all patients to be in New York Heart Association functional class I or II with no late cardiac or abdominal events. We conclude that simultaneous coronary artery bypass grafting and abdominal aortic surgery on the beating heart is safe and effective, and has a low perioperative clinical morbidity rate. To our knowledge, ours is the 1st report on this procedure. Larger studies with longer follow-up are needed.