Transmyocardial laser revascularisation in acutely ischaemic myocardium

Objective: Although recent experience suggests that transmyocardial laser revascularisation (TMLR) relieves angina, its mechanism of action remains undefined. We examined its functional effects and analysed its morphological features in an animal model of acute ischaemia. Methods: A total of 15 pigs were randomised to ligation of left marginal arteries (infarction group, n=5), to TMLR of the left lateral wall using a holmium:yttrium-aluminium garnet (Ho:YAG) laser (laser group, n=5), and to both (laser-infarction group, n=5). All the animals were sacrificed 1 month after the procedure. Haemodynamics and echocardiography with segmental wall motion score were carried out at both time intervals (scale 0-3: 0, normal; 1, hypokinesia; 2, akinesia; 3, dyskinesia). Histology of the involved area was analysed. Results: Laser group showed no change of the segmental wall motion score of the involved area 30 min after the laser channels were made (score: 0±0). Infarction and laser-infarction groups both showed a persistent and definitive increase of the segmental wall motion score (at 30 min: 1.6±0.3 and 2±0, respectively; at 1 month: 1.8±0.2 and 1.8±0.4, respectively). These increases were all statistically significant in comparison with baseline values (P<0.5), however comparison between infarction and laser-infarction groups showed no significant difference. On macroscopic examination of the endocardial surface, no channel was opened. On histology, there were signs of neovascularisation around the channels in the laser group, whereas in the laser-infarction group the channels were embedded in the infarction scar. Conclusions: In this acute pig model, TMLR did not provide improvement of contractility of the ischaemic myocardium. To the degree that the present study pertains to the clinical setting, the results suggest that mechanisms other than blood flow through the channels should be considered, such as a laser-induced triggering of neovascularisation or neural destructio

P682Preserved contractile function of unloaded cardiomyocytes despite diminished sarcomere size is associated with troponin I activation

Objective: Myocardial unloading with ventricular assist devices in patients with severe heart failure (HF) can lead to reversal of certain aspects of pathological remodeling. However, these effects do not translate into recovery of myocardial function in the human heart, possibly due to detrimental atrophic processes also elicited through unloading. We have studied the effects of long-term unloading on sarcomeric morphology and function in a small animal model of ventricular unloading, heterotopic heart transplantation (HTX) in rats. Methods: Native rat hearts were unloaded via HTX for 30 days, CMs from control and unloaded hearts were isolated (n=8 hearts/>250 individual cells/group). CM overall size was determined, sarcomere length/contractility assessed and Calcium transients as well as E-C coupling gain analyzed in patch-clamped CMs. Additionally, phosphorylation of Troponin I, indicative of sarcomere activation, was measured with western blotting. Results: CM cross-sectional area was diminished in unloaded cells by about one third (2787±345 vs 1993±230 μm2) as was cell capacitance in patched cells. Accordingly, baseline sarcomere length was significantly reduced by ~0.2μm (Figure). However, this reduction did not diminish contractile function: fractional shortening was significantly higher in unloaded CMs (8.0 ± 3 % vs 6.6 ± 2.5 % in CTR, p = 0.01). Departure velocity of the transients was similar (-135.2 ± 48 vs -119.4 ± 40 dL/dt), and return velocity was slightly increased in unloaded cells (120.7 ± 54 vs 94.0 ± 46 dL/dt, p < 0.05), indicating preserved relaxation. Calcium transient amplitudes and current-voltage relationship under basal condition and isoproterenol stimulation was not changed. Troponin I phosphorylation was elevated and may contribute to the maintenance of sarcomeric function in long-term unloaded CMs. Conclusion: Although there are limitations regarding assessment of contractility in isolated cells, we may conclude that the considerable size reduction in CMs induced by unloading does not translate into diminished contractile function or E-C couplin

CO17 107. Experiencia inicial con la prótesis de válvula aórtica sin sutura 3f-enable de segunda generación

ObjetivosLa válvula aórtica ATS-3F-Enable™ representa una nueva generación con pericardio equino, stent de nitinol autoexpandible e implantación sin suturas. Evaluamos la técnica de implantación, la seguridad y efectividad de la válvula así como los resultados al año de implantación.Material y métodosAnálisis de resultados en una serie de 27 pacientes consecutivos con estenosis de válvula aórtica y reemplazamiento aislado de la válvula por una ATS-3F-Enable™ entre agosto de 2007 y febrero de 2009. La edad media fue 75,7±6,6 años. Diecisiete mujeres (63%). EuroSCORE mediano: 8, y medio: 7,1±1,7.ResultadosEl tamaño medio de válvula implantada fue de 23mm (franja: 19-27mm). La media de tiempo de clampaje aórtico fue de 39,8±15min (franja: 29-103min). La media de tiempo de circulación extracorpórea fue de 58,6±20min (franja: 41-127). La media de tiempo de hospitalización fue de 11 días (7-22). No hubo mortalidad durante la intervención. Al alta, los gradientes de presión transvalvular medio y alto con ecocardiografía fueron de 11,6 y 18,5mmHg, respectivamente. Dos pacientes presentaron una fuga paravalvular moderada y un paciente fue reoperado a causa de una fuga paravalvular grave. Se requirió la implantación de marcapasos en cinco pacientes (18,5%). El seguimiento al cabo de 1 año fue del 100% y la supervivencia fue del 86%.ConclusionesLa prótesis aórtica ATS-3F-Enable™ puede ser implantada con seguridad y presenta resultados hemodinámicos favorables. El stent autoexpandible y la técnica sin sutura permite una implantación rápida, sin embargo, no tan rápida como esperado. Acumulación de experiencia y algunas modificaciones en el diseño de la prótesis podrán ayudar a perfeccionar la técnica

Risk factors for asymptomatic abdominal aortic aneurysm: systematic review and meta-analysis of population-based screening studies.

BACKGROUND: The incidence of and mortality from ruptured abdominal aortic aneurysm (AAA) is increasing. There is uncertainty regarding the indicators which could be used to identify groups at high risk. This issue has been addressed in a systematic review of population-based screening studies. METHODS: MEDLINE and EMBASE were searched, reference lists scanned and manual searches made of eight journals. The search was restricted to four languages (English, German, French and Italian). Population-based studies investigating risk factors associated with screening-detected AAA were included. The following risk factors were considered: sex, smoking, hypertension, diabetes, a history myocardial infarction, and peripheral vascular disease. RESULTS: Fourteen cross-sectional studies met our inclusion criteria. Most studies screened people aged 60 years or older. The prevalence of AAA ranged from 4.1% to 14.2% in men and from 0.35% to 6.2% in women. Male sex showed a strong association with AAA (OR 5.69), whereas smoking (OR 2.41), a history of myocardial infarction (OR 2.28) or peripheral vascular disease (OR 2.50) showed moderate associations. Hypertension was only weakly associated with AAA (OR 1.33) and no association was evident with diabetes (OR 1.02). CONCLUSIONS: The efficacy of screening men aged 60 years or older and women of the same age who smoke or have a history of peripheral or coronary artery disease should be evaluated in randomized controlled trials

Are there accurate predictors of long-term vital and functional outcomes in cardiac surgical patients requiring prolonged intensive care?

BACKGROUND AND OBJECTIVE: The decision to maintain intensive treatment in cardiac surgical patients with poor initial outcome is mostly based on individual experience. The risk scoring systems used in cardiac surgery have no prognostic value for individuals. This study aims to assess (a) factors possibly related to poor survival and functional outcomes in cardiac surgery patients requiring prolonged (&gt; or = 5 days) intensive care unit (ICU) treatment, (b) conditions in which treatment withdrawal might be justified, and (c) the patient's perception of the benefits and drawbacks of long intensive treatments. METHODS: The computerized data prospectively recorded for every patient in the intensive care unit over a 3-year period were reviewed and analyzed (n=1859). Survival and quality of life (QOL) outcomes were determined in all patients having required &gt; or =5 consecutive days of intensive treatment (n=194/10.4%). Long-term survivors were interviewed at yearly intervals in a standardized manner and quality of life was assessed using the dependency score of Karnofsky. No interventions or treatments were given, withhold, or withdrawn as part of this study. RESULTS: In-hospital, 1-, and 3-year cumulative survival rates reached 91.3%, 85.6%, and 75.1%, respectively. Quality of life assessed 1 year postoperatively by the score of Karnofsky was good in 119/165 patients, fair in 32 and poor in 14. Multivariate logistic regression analysis of 19 potential predictors of poor outcome identified dialysis as the sole factor significantly (p=0.027) - albeit moderately - reducing long-term survival, and sustained neurological deficit as an inconstant predictor of poor functional outcome (p=0.028). One year postoperatively 0.63% of patients still reminded of severe suffering in the intensive station and 20% of discomfort. Only 7.7% of patients would definitely refuse redo surgery. CONCLUSIONS: This study of cardiac surgical patients requiring &gt; or =5 days of intensive treatment did not identify factors unequivocally justifying early treatment limitation in individuals. It found that 1-year mortality and disability rates can be maintained at a low level in this subset of patients, and that severe suffering in the ICU is infrequent

Hemodynamics optimization during off-pump coronary artery bypass: the 'no compression' technique

OBJECTIVE: Heart manipulation during OPCAB may cause hemodynamical instability in particular for access to the posterior and lateral walls. The 'no compression' technique involves enucleation of the heart without any compression on the cavities, and stabilization of the target area with a suction device. The impact of this technique on hemodynamics is assessed. METHODS: In order to analyze a homogeneous group, 26 consecutive patients with triple grafts, one to each side of the heart in the same sequential order (posterior, lateral and anterior wall successively) were selected. Heart rate (HR), mean pulmonary arterial pressure (PAP, mmHg), pulmonary capillary wedge pressure (PCWP, mmHg), mean arterial pressure (MAP, mmHg), cardiac output index (COI, l/min per m(2)), and central venous saturation (SvO(2),%) were monitored. A coronary shunt was used for all the anastomoses. RESULTS: HR was stable with baseline value of 60+/-10 and the highest value for the anterior wall, 63.6+/-8 (P=0.23). PAP and PCWP exhibited their highest increase, when compared with baseline, for the lateral wall, 23.9+/-4.7 vs. 20.7+/-6.2 (P=0.06), and 17.2+/-4.7 vs. 14.9+/-5.6 (P=0.16), respectively. MAP, COI and SvO(2), exhibited their largest drop, when compared with baseline, for the lateral wall too, 73.1+/-9.1 vs. 77.1+/-7.5 (P=0.12), 1.99+/-0.47 vs. 2.26+/-0.55 (P=0.09), and 70.5+/-8.4 vs. 74.8+/-9.3 (P=0.12), respectively. CONCLUSIONS: None of the hemodynamical parameter differed significantly from baseline value for all three territories. While hemodynamics was perfectly maintained during the posterior and anterior walls revascularization, exposure of the lateral wall led to marginal changes only

Augmented venous return for minimally invasive open heart surgery with selective caval cannulation

OBJECTIVE: Minimally invasive open heart surgery involves limited intrathoracic cannulation sites necessitating cardiopulmonary bypass to be initiated via peripheral access using percutaneous cannulae with the tip placed into the right atrial cavity. However, surgery involving the opening of the right heart obliges the surgeon to maintain the end of the cannulae into the vena cavae. The impeded venous return due to the smaller diameter may be alleviated by inserting a centrifugal pump in the venous line. METHODS: Right anterior mini-thoracotomy and exposure of the femoral site were performed before the patient was heparinized. Cannulation of the femoral artery, the inferior vena cava via the femoral vein and the superior vena cava through the mini-thoracotomy was performed and cardiopulmonary bypass was initiated. Venous drainage was augmented with the centrifugal pump. Cardiac arrest was provoked and both vena cavae were snared before performing the intracardiac procedure. RESULTS: Twenty consecutive patients were operated on using this technique (15 males/five females; age: 44.8 +/- 14.3 years; bodyweight: 73.5 +/- 15.1 kg; body surface area: 1.8 +/- 0.2 m2; theoretical blood flow rate: 4.4 +/- 0.5 l/min). The cannula sizes were 21.9 +/- 2.2 Fr for the femoral artery, 26.5 +/- 1.7 Fr for the inferior vena cava and 23.8 +/- 2.5 Fr for the superior vena cava. Venous drainage through the single inferior vena cava cannula was 2.1 +/- 0.6 l/min (48.8 +/- 13.3% of the theoretical flow). Adding the superior vena cava cannula increased the venous flow to 3.1 +/- 0.4 l/min (70.7 +/- 9.6% of the theoretical value, P &lt; 0.005). The use of the centrifugal pump increased the flow to 4.1 +/- 0.6 l/min (93.4 +/- 8.9% of the theoretical flow, P &lt; 0.001) with a mean inlet negative pressure of -69 +/- 10.2 mmHg. The mean bypass time was 64.0 +/- 24.6 min for a mean operative time of 226.3 +/- 61.0 min. Minimum venous saturation was 69.4 +/- 8.5%. CONCLUSIONS: Despite the smaller diameter of the vena cavae compared to the right atrium, and a smaller internal diameter of percutaneous cardiopulmonary bypass cannulae compared to classic ones; the centrifugal pump improves the venous drainage significantly so that minimally invasive open heart procedures can be performed under optimal and safe perfusion conditions

Hyperglycemic Myocardial Damage Is Mediated by Proinflammatory Cytokine: Macrophage Migration Inhibitory Factor

Diabetes has been regarded as an inflammatory condition which is associated with left ventricular diastolic dysfunction (LVDD). The purpose of this study was to examine the expression levels of macrophage migration inhibitory factor (MIF) and G protein-coupled receptor kinase 2 (GRK2) in patients with early diabetic cardiomyopathy, and to investigate the mechanisms involved in MIF expression and GRK2 activation.83 patients in the age range of 30-64 years with type 2 diabetes and 30 matched healthy men were recruited. Left ventricular diastolic function was evaluated by cardiac Doppler echocardiography. Plasma MIF levels were determined by ELISA. To confirm the clinical observation, we also studied MIF expression in prediabetic rats with impaired glucose tolerance (IGT) and relationship between MIF and GRK2 expression in H9C2 cardiomyoblasts exposed to high glucose.Compared with healthy subjects, patients with diabetes have significantly increased levels of plasma MIF which was further increased in diabetic patients with Left ventricular diastolic dysfunction (LVDD). The increased plasma MIF levels in diabetic patients correlated with plasma glucose, glycosylated hemoglobin and urine albumin levels. We observed a significant number of TUNEL-positive cells in the myocardium of IGT-rats but not in the control rats. Moreover, we found higher MIF expression in the heart of IGT with cardiac dysfunction compared to that of the controls. In H9C2 cardiomyoblast cells, MIF and GRK2 expression was significantly increased in a glucose concentration-dependant manner. Furthermore, GRK2 expression was abolished by siRNA knockdown of MIF and by the inhibition of CXCR4 in H9C2 cells.Our findings indicate that hyperglycemia is a causal factor for increased levels of pro-inflammatory cytokine MIF which plays a role in the development of cardiomyopathy occurring in patients with type 2 diabetes. The elevated levels of MIF are associated with cardiac dysfunction in diabetic patients, and the MIF effects are mediated by GRK2

No relationship between thymidine phosphorylase (TP, PD-ECGF) expression and hypoxia in carcinoma of the cervix

The expression of hypoxia-regulated genes promotes an aggressive tumour phenotype and is associated with an adverse cancer treatment outcome. Thymidine phosphorylase (TP) levels increase under hypoxia, but the protein has not been studied in association with hypoxia in human tumours. An investigation was made, therefore, of the relationship of tumour TP with hypoxia, the expression of other hypoxia-associated markers and clinical outcome. This retrospective study was carried out in patients with locally advanced cervical carcinoma who underwent radiotherapy. Protein expression was evaluated with immunohistochemistry. Hypoxia was measured using microelectrodes and the level of pimonidazole binding. There was no relationship of TP expression with tumour pO2 (r=−0.091, P=0.59, n=87) or pimonidazole binding (r=0.13, P=0.45, n=38). There was no relationship between TP and HIF-1α, but there was a weak borderline significant relationship with HIF-2α expression. There were weak but significant correlations of TP with the expression of VEGF, CA IX and Glut-1. In 119 patients, the presence of TP expression predicted for disease-specific (P=0.032) and metastasis-free (P=0.050) survival. The results suggest that TP is not a surrogate marker of hypoxia, but is linked to the expression of hypoxia-associated genes and has weak prognostic power

Volvulus de l'intestin grêle comme cause primaire d'abdomen aigu [Volvulus of the small intestine as a cause of primary acute abdomen].

As a cause of small intestine occlusion, volvulus is often a consequence of a band or adhesions. Except in infants, it is rarely the primary cause of symptomatology. Between January 1976 and December 1992, 13 patients (7 women and 6 men, mean age of 56.8 years) were admitted in our department for an acute abdomen due to a spontaneous primary volvulus of the small bowel. Clinical examination and laboratory tests did not help in preoperative diagnosis. All patients underwent an explorative laparotomy. Six patients had had prior abdominal surgery but none of them presented adhesion or band. In 8 patients (62%), detorsion was sufficient. Resection of a segment of small bowel was necessary in 4 patients. Gangrenous of the entire bowel was observed in one patient who rapidly died. Two patients presented minor complications. One patient with Down syndrome died of bronchoaspiration. One patient has been reoperated on one year later for recurrence of the volvulus, and underwent a Noble procedure. We conclude that volvulus of the small bowel is a rare cause of acute abdomen that must be remembered. Early surgery is mandatory to reduce the risk of gangrene, which is known to double the mortality. Laparoscopy will be helpful in early diagnosis and therapy