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Models of the stock market often focus on predicting the direction of the stock market. Instead of following this approach, we created a model to predict the daily absolute percent change of the S&P 500. An accurate model of this metric would greatly increase profitability of option trading strategies such as straddles and iron condors. In this project, novel features were created based on historical data and fed to machine learning algorithms such as Decision Trees, Rule Based Classifiers, K-mean Clusters, and Kernels. Based on our findings, Decision Trees and Kernels showed an accuracy of 80% when predicting absolute percent change, while Rule Based Classifiers had an accuracy of 88%. [ABSTRACT FROM AUTHOR]

Objectives: Patients with acute myocardial infarction pretreated with prasugrel or ticagrelor may require urgent coronary artery bypass grafting (CABG). However, prasugrel and ticagrelor withdrawal period is recommended for 5-7 days before planned CABG to enable full platelet recovery. We hypothesized that monitoring sequential platelet reactivity (PR) could identify patients with early platelet recovery who may benefit from earlier surgery before the guideline-recommended 5-7 day delay., Patients and Methods: We performed preoperative PR assays in 35 patients with acute myocardial infarction who received prasugrel (60%) or ticagrelor (40%) and required an urgent CABG. When platelet inhibition levels were favorable, on the basis of the VerifyNow assay, surgery was endorsed. CABG-related bleeding parameters were collected and compared with two matched control groups composed of patients who received fewer potent antiplatelet regimens., Results: On the basis of platelet function monitoring, we identified 21 (56.7%) patients with a relatively earlier platelet recovery who underwent CABG before the end of the conventional washout period (5-7 days). For these patients, the washout periods were shortened to an average time of 2.6±1.0 days for ticagrelor and 3.8±1.5 days for prasugrel. CABG-related bleeding parameters were comparable with the two matched control groups., Conclusion: A strategy of performing preoperative PR assays can identify patients who recover platelet function in less than 5-7 days after ticagrelor or prasugrel discontinuation. This strategy may provide the basis for performing urgent CABGs earlier than the currently recommended delay. Future, larger studies are required to establish these preliminary findings.

An electrochemical biosensor has been developed for ultrasensitive, label-free determination of protein kinase activity. The sensor is composed of a unique peptide monolayer on a gold electrode. It identifies the order change in the monolayer upon phosphorylation, via square wave voltametry (SWV) measurements. Disorder caused by the introduction of the phosphate groups onto the middle of the peptide sequence results in pinhole formation and therefore an increase in the electrochemical signal. The measured sensitivity was 100 nM of kinase and the dynamic range was 100 nM up to 11 μM. Sensitivity was an order of magnitude higher, and the dynamic range wider by two orders of magnitude, as compared to our previously reported impedimetric method, in which the sensitivity was 1 μM, and the dynamic range was 1-20 μM., (© 2015 Wiley Periodicals, Inc.)

Purpose: To evaluate functional electrical stimulation (FES) neuroprothesis as a method to improve gait in hemiplegic patients, using three different gait scoring methods as measures., Methods: Five hemiplegic patients (four with cerebral palsy at GMFCS I, one with diffuse pontine glioma) with a mean age of 16.5 years were given a FES neuroprosthesis (NESS(®) L300™) that was applied and calibrated individually. After an adaptation period during which the participants increased their daily use of the neuroprosthesis, gait was assessed with the stimulation off and with the FES on. Kinematic, kinetic, and temporal spatial data were determined using motion analysis and summarized by three scoring methods: Gait Profile Score (GPS), Gait Deviation Index (GDI), and Gillette Gait Index (GGI). Indices were calculated using the Gaitabase program available online. Patients were followed for a minimum of 1 year., Results: When comparing gait with and without stimulation, all scoring methods showed improvement. GPS and GDI of the affected leg were significantly improved: 12.23-10.23° (p = 0.017) and 72.36-78.08 (p = 0.002), respectively. By applying the movement analysis profile, the decomposed GPS score, we found that only the ankle dorsiflexion and the foot progression angle were significantly changed. GGI of the affected leg showed improvement, but without statistical significance: 168.88-131.64 (p = 0.221). Total GPS of legs and the GPS, GDI, and GGI of the nonaffected leg showed improvement without statistical significance. At the 1-year follow-up, all patients expressed high satisfaction and continued to use the device., Conclusions: Dorsiflexion functional electrical stimulation improves gait in hemiplegic patients, as reflected by GPS, GDI, and GGI.

Background: Circulating endothelial progenitor cells (EPCs) are recruited from the blood system to sites of ischemia and endothelial damage, where they contribute to the repair and development of blood vessels. Since numerous eicosanoids including leukotrienes (LTs) and hydroxyeicosatetraenoic acids (HETEs) have been shown to exert potent pro-inflammatory activities, we examined their levels in chronic diabetic patients with severe cardiac ischemia in conjunction with the level and function of EPCs., Results: Lipidomic analysis revealed a diabetes-specific increase (p<0.05) in inflammatory and angiogenic eicosanoids including the 5-lipoxygenase-derived LTB (4.11±1.17 vs. 0.96±0.27 ng/ml), the lipoxygenase/CYP-derived 12-HETE (117.08±35.05 vs. 24.34±10.03 ng/ml), 12-HETrE (17.56±4.43 vs. 4.15±2.07 ng/ml), and the CYP-derived 20-HETE (0.32±0.04 vs. 0.06±0.05 ng/ml) the level of which correlated with BMI (p=0.0027). In contrast, levels of the CYP-derived EETs were not significantly (p=0.36) different between these two groups. EPC levels and their colony-forming units were lower (p<0.05) with a reduced viability in diabetic patients compared with non-diabetics. EPC function (colony-forming units (CFUs) and MTT assay) also negatively correlated with the circulating levels of HgA1C., Conclusion: This study demonstrates a close association between elevated levels of highly pro-inflammatory eicosonoids, diabetes and EPC dysfunction in patients with cardiac ischemia, indicating that chronic inflammation impact negatively on EPC function and angiogenic capacity in diabetes., (Copyright © 2012 Elsevier Inc. All rights reserved.)

This paper describes remarkably high sensitivities in the label-free detection of kinase-promoted phosphorylation for 14 different peptide substrates on electrode-immobilized monolayers (gold or nitride) using serine/threonine kinases PKA, PKC, and CaMK2. Peptide substrates were preselected using (33)P-labeling in a microarray of 1024 substrates. The three most active peptides (A1-A3, C1-C3, and M1-M3) were investigated using electrochemical impedance spectroscopy (EIS) and ion-sensitive field effect transistors (ISFETs). Some of the peptide substrates, for example, the PKC-specific substrate PPRRSSIRNAH (C1), showed a remarkably high sensitivity in the EIS-based sensor measurements. Our studies revealed that this high sensitivity is primarily due to the monolayer's packing density. Nanoscopic studies demonstrated a distinct disordering of the C1-monolayer upon phosphorylation, while phosphatase-promoted dephosphorylation regenerated the highly ordered peptide monolayer. As a matter of fact, the initial surface packing of the peptide monolayer mainly determined the level of sensitivity, whereas electrostatic repulsion of the redox-active species was found to be much less important., (© 2011 American Chemical Society)

Objective: Our objective was to assess the effect of the timing of cardiac angiography, contrast media dose, and preoperative renal function on the prevalence of acute renal failure after cardiac surgery., Methods: Data on 395 consecutive patients who underwent coronary artery bypass grafting were prospectively collected. Creatinine clearance was estimated by the Cockcroft-Gault equation. Patients were divided into 3 groups according to the time between cardiac angiography and surgery (group A, < or = 1 day; group B, > 1 day and < or = 5 days; group C, > 5 days). Patients who underwent a salvage operation or were receiving dialysis before surgery were excluded. Acute renal failure was defined as 25% decrease from baseline of estimated creatinine clearance and estimated creatinine clearance of 60 mL/min or less on postoperative day 3. Owing to differences in preoperative characteristics between groups, propensity score analysis was used to adjust those differences., Results: Acute renal failure developed in 13.6% of patients. Hospital mortality was 3.3% and was higher in patients in whom acute renal failure developed (22%) versus those in whom it did not (0.3%; P < .001). Multivariable analysis identified preoperative estimated creatinine clearance of 60 mL/min or less (odds ratio [OR], 7.1), operation within 24 hours of catheterization (OR = 3.7), use of more than 1.4 mL/kg of contrast media (OR = 3.4), lower hemoglobin level (OR = 1.3), older age (OR = 1.1), and lower weight (OR = 0.95) as independent predictors of postoperative acute renal failure. Analysis of interaction between contrast dose and time of surgery revealed that high contrast dose (>1.4 mL/kg) predicted acute renal failure if surgery was performed up to 5 days after angiography., Conclusions: Whenever possible, coronary bypass grafting should be delayed for at least 5 days in patients who received a high contrast dose, especially if they also have preoperative reduced renal function., (Copyright 2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Mechanisms for controlling symbiont populations are critical for maintaining the associations that exist between a host and its microbial partners. We describe here the transcriptional, metabolic, and ultrastructural characteristics of a diel rhythm that occurs in the symbiosis between the squid Euprymna scolopes and the luminous bacterium Vibrio fischeri. The rhythm is driven by the host's expulsion from its light-emitting organ of most of the symbiont population each day at dawn. The transcriptomes of both the host epithelium that supports the symbionts and the symbiont population itself were characterized and compared at four times over this daily cycle. The greatest fluctuation in gene expression of both partners occurred as the day began. Most notable was an up-regulation in the host of >50 cytoskeleton-related genes just before dawn and their subsequent down-regulation within 6 h. Examination of the epithelium by TEM revealed a corresponding restructuring, characterized by effacement and blebbing of its apical surface. After the dawn expulsion, the epithelium reestablished its polarity, and the residual symbionts began growing, repopulating the light organ. Analysis of the symbiont transcriptome suggested that the bacteria respond to the effacement by up-regulating genes associated with anaerobic respiration of glycerol; supporting this finding, lipid analysis of the symbionts' membranes indicated a direct incorporation of host-derived fatty acids. After 12 h, the metabolic signature of the symbiont population shifted to one characteristic of chitin fermentation, which continued until the following dawn. Thus, the persistent maintenance of the squid-vibrio symbiosis is tied to a dynamic diel rhythm that involves both partners.

Background: The differences in hand functionality after harvesting the radial artery for coronary artery bypass grafting (CABG) in an endoscopic technique relative to open technique are unclear., Methods: One hundred and sixty-four patients who had CABG and their non dominant hand radial artery was harvested either in an open technique (n = 92) or in an endoscopic technique (n = 72) in a period of 9.8 +/- 3.5 months after the operation were studied. Surgical technique was surgeon specific. Patients were asked either five questions (endoscopic group), or six questions (open group), to assess how radial artery harvesting affected them., Results: Significantly more patients in the open group experienced significant limitations in their work and regular daily activities (12% versus 0%, p = 0.02), social activities (13% versus 0%, p = 0.005), and experienced significant pain (8% versus 0%, p = 0.04) compared with the endoscopic group. More patients in the open group complained that their arm incision disturb them (24% versus 10%, p = 0.01). Forty-two patients (46%) in the open group would prefer smaller incision. A "limitation score" variable was created from the first four questions to reflect overall functionality. Severe limitation was present in 3% of the open group versus 0% in the endoscopic group (p = 0.04). Female sex and open harvesting technique were found to be independently associated with higher limitation score., Conclusions: After a mean of 9.8 months after surgery, patients reports good overall upper-limb function. However, more patients in the open technique had significant disabilities and dissatisfaction.

Objective: Radial artery harvesting using the less invasive endoscopic technique involves dissection in a narrow tunnel and may cause an injury or induce vasospasm to the conduit. To assess this hypothesis, radial artery segments harvested endoscopically or conventionally were studied for reactivity and integrity., Methods: Rings of radial arteries from 80 CABG patients who had their radial artery harvested either open (n=40) or endoscopic (n=40), were attached to a force transducer then subjected to norepinephrine (NE, 10(-6)M), acetylcholine (ACh, 10(-5)M), followed by sodium nitroprusside (SNP, 10(-7) to 10(-5)M) to test endothelial dependent and non-dependent relaxation. Vessels' integrity was assessed by microscopic staining with hematoxylin-eosin for muscle layers, Masson trichrome for collagen content and von Gieson for elastica layers., Results: Contraction and relaxation in response to NE, ACh and SNP were similar in both techniques. Arterial layers, collagen content and elastic lamina were preserved in all radial rings. Both techniques were found to be equally efficient in physiological and microscopic tests., Conclusions: The similar reactivity and integrity of the radial artery in both techniques should encourage the less invasive endoscopic approach.

The light-organ symbiosis between the squid Euprymna scolopes and the luminous bacterium Vibrio fischeri offers the opportunity to decipher the hour-by-hour events that occur during the natural colonization of an animal's epithelial surface by its microbial partners. To determine the genetic basis of these events, a glass-slide microarray was used to characterize the light-organ transcriptome of juvenile squid in response to the initiation of symbiosis. Patterns of gene expression were compared between animals not exposed to the symbiont, exposed to the wild-type symbiont, or exposed to a mutant symbiont defective in either of two key characters of this association: bacterial luminescence or autoinducer (AI) production. Hundreds of genes were differentially regulated as a result of symbiosis initiation, and a hierarchy existed in the magnitude of the host's response to three symbiont features: bacterial presence > luminescence > AI production. Putative host receptors for bacterial surface molecules known to induce squid development are up-regulated by symbiont light production, suggesting that bioluminescence plays a key role in preparing the host for bacteria-induced development. Further, because the transcriptional response of tissues exposed to AI in the natural context (i.e., with the symbionts) differed from that to AI alone, the presence of the bacteria potentiates the role of quorum signals in symbiosis. Comparison of these microarray data with those from other symbioses, such as germ-free/conventionalized mice and zebrafish, revealed a set of shared genes that may represent a core set of ancient host responses conserved throughout animal evolution.

Microarray analyses have contributed greatly to the rapid understanding of functional genomics through the identification of gene networks as well as gene discovery. To facilitate functional genomics of the inner ear, we have developed a mouse inner-ear-pertinent custom microarray chip (CMA-IE1). Nonredundant cDNA clones were obtained from two cDNA library resources: the RIKEN subtracted inner ear set and the NIH organ of Corti library. At least 2000 cDNAs unique to the inner ear were present on the chip. Comparisons were performed to examine the relative expression levels of these unique cDNAs within the organ of Corti, lateral wall, and spiral ganglion. Total RNA samples were obtained from the three cochlear-dissected fractions from adult CF-1 mice. The total RNA was linearly amplified, and a dendrimer-based system was utilized to enhance the hybridization signal. Differentially expressed genes were verified by comparison to known gene expression patterns in the cochlea or by correlation with genes and gene families deduced to be present in the three tissue types. Approximately 22-25% of the genes on the array had significant levels of expression. A number of differentially expressed genes were detected in each tissue fraction. These included genes with known functional roles, hypothetical genes, and various unknown or uncharacterized genes. Four of the differentially expressed genes found in the organ of Corti are linked to deafness loci. None of these are hypothetical or unknown genes.

As part of the trans-National Institutes of Health (NIH) Mouse Brain Molecular Anatomy Project (BMAP), and in close coordination with the NIH Mammalian Gene Collection Program (MGC), we initiated a large-scale project to clone, identify, and sequence the complete open reading frame (ORF) of transcripts expressed in the developing mouse nervous system. Here we report the analysis of the ORF sequence of 1274 cDNAs, obtained from 47 full-length-enriched cDNA libraries, constructed by using a novel approach, herein described. cDNA libraries were derived from size-fractionated cytoplasmic mRNA isolated from brain and eye tissues obtained at several embryonic stages and postnatal days. Altogether, including the full-ORF MGC sequences derived from these libraries by the MGC sequencing team, NIH&#95;BMAP full-ORF sequences correspond to approximately 20% of all transcripts currently represented in mouse MGC. We show that NIH&#95;BMAP clones comprise 68% of mouse MGC cDNAs > or =5 kb, and 54% of those > or =4 kb, as of March 15, 2004. Importantly, we identified transcripts, among the 1274 full-ORF sequences, that are exclusively or predominantly expressed in brain and eye tissues, many of which encode yet uncharacterized proteins.

Background: The role of intraoperative transesophageal echocardiography (IOTEE) in valve replacement surgery is not well established. The aim of this study was to explore the impact of immediate postpump IOTEE in valve replacement surgery at a single tertiary medical center., Methods: The departmental database was screened for valve replacement operations (mechanical or bioprosthetic valves) performed during a 55-month period that were succeeded by immediate postpump IOTEE. Data was gathered regarding the impact of IOTEE on the immediate postoperative course., Results: The study group included 417 patients (44.8% male, 55.2% female, age 65.2 +/- 13.9 years). Prepump IOTEE was performed in 352 patients (84.4%). A single valve was replaced in 336 patients (80.6%) and two or more valves were replaced in 81 patients (19.4%). Overall 501 valves were inserted: mitral, 237 (131 mechanical, 106 biological); aortic, 221 (89 mechanical, 132 biological); tricuspid, 43 (2 mechanical, 41 biological). Unexpected pathologic echocardiographic findings on postpump IOTEE necessitated immediate surgical correction in 15 patients (3.6%): perivalvular leak in 8 patients (4 mitral, 4 aortic), immobilized leaflet in 4 patients (3 mitral, 1 tricuspid), coronary obstruction by an aortic bioprosthesis in 2 patients, and incompetent xenograft in 1 patient. Prolonged removal of air was necessary in 45 patients (10.8%). In 47 patients (11.3%) the postpump IOTEE contributed to the evaluation of difficult weaning from the bypass pump and to its appropriate therapeutic management (volume expansion, inotropic agents, vasodilators, or mechanical assistance)., Conclusions: Immediate postpump IOTEE is an important diagnostic and therapeutic role in valve replacement surgery and should be widely implemented.

Background: Off-pump coronary artery bypass (OPCAB) is believed to reduce cardiopulmonary bypass (CPB)-related complications, including platelet damage. A hypercoagulable state instead of coagulopathy has been reported following OPCAB surgeries due to CPB. Whether platelet function is changed when the injurious effect of CPB is eliminated was investigated., Methods: Platelet function was determined with the cone and plate(let) analyzer (CPA) method. The 2 parameters, average size (AS) and surface coverage (SC) of platelet aggregates, were measured with the CPA method to assess platelet aggregation and adhesion. These parameters were evaluated, and their values were compared at several stages of OPCAB surgery. The correlations of postoperative bleeding with platelet function at different stages of the surgery and with other factors, such as platelet count, hematocrit, and transfusions, were studied., Results: Both AS and SC increased during several stages of the operation, and postoperative values (mean +/- SD) were significantly higher than preoperative values (30.4 +/- 8.1 microm 2 versus 23.3 +/- 6.9 microm 2 for AS [ P =.02] and 7.6% +/- 3.6% versus 5.2% +/- 1.8% for SC [ P =.04]). The mean total bleeding volume was 875 micro 415 mL. Preoperative AS and SC were the only parameters significantly ( P =.01) and linearly ( r = 0.7) related to postoperative bleeding., Conclusions: An increased platelet function, as determined by the CPA method, is found following OPCAB surgery. This phenomenon is probably at least partially responsible for the thrombogenic state after OPCAB surgery. Lack of platelet injury attributed to CPB may divert the system toward a more thrombogenic state. Preoperative platelet function, as evaluated by the CPA method, is an independent risk factor determining postoperative bleeding.

Background: Concomitant mitral valve regurgitation is often present in patients with aortic stenosis. The additional MV replacement is associated with high operative risk. Previous studies have shown an amelioration of MV regurgitation after aortic valve replacement but most of the patient groups were heterogenous., Objectives: To determine whether AV replacement for aortic stenosis has any effect on MV regurgitation., Methods: We reviewed two-dimensional echocardiography and color flow Doppler assessment of both aortic stenosis and MV regurgitation severity in 30 patients. Patients with previous MV surgery, organic MV disease, occlusive carotid artery disease, ejection fraction < 50%, and coexisting significant AV regurgitation were excluded. Preoperatively, MV regurgitation was mild in 23 patients (77%) and moderate in 7 (23%); in no patient was the condition severe. All patients had severe atrial stenosis (peak average aortic gradient 86 +/- 22 mmHg in the mild MV regurgitation group and 83 +/- 26 mmHg in the moderate group). The patients were divided into two groups according to the severity of MV regurgitation (associated mild, and moderate). Group 2, with moderate MV regurgitation, was the most problematic in terms of decision making for concomitant MV surgery. Therefore, additional assessment of several parameters was required., Results: There was a significant decrease in MV regurgitation area (7.6 +/- 1.9 vs. 3.0 +/- 1.2 cm2, P < or = 0.012) and percent (28 +/- 5% vs. 12 +/- 6%, P < or = 0.001) between pre- and postoperative evaluation. Thus, the severity of the condition in all patients with moderate MV regurgitation decreased after AV replacement; in the mild group it remained unchanged in 53% or improved in 47%. There was no association between the preoperative gradient on the aortic valve and the degree of MV regurgitation., Conclusions: In our population of patients with severe atrial stenosis there were no patients with coexisting severe MV regurgitation. The decision to repair or replace a severely leaking mitral valve is an easy one, as in mild MV regurgitation. The clinical problem often presents in patients with severe aortic stenosis and moderate MV regurgitation. We believe that additional MV surgery is not necessary, at least in patients with preserved left ventricular function and without organic MV disease.

Background: Postoperative atrial fibrillation after cardiac operation is common. Despite the identification of risk factors associated with postoperative atrial fibrillation, the pathophysiologic mechanisms remain unclear. Myolysis has been recently described to be associated with maintenance of atrial fibrillation in experimental animals. In this study, we attempted to identify histopathologic changes in atria that might predict the development of postoperative atrial fibrillation, and specifically address its association with myolysis., Methods: Right appendicular atrial tissue was sampled before and after cardiopulmonary bypass from 60 patients in sinus rhythm who underwent elective coronary artery bypass grafting., Results: Fifteen patients (25%) developed postoperative atrial fibrillation. Histopathologic abnormalities were found in most patients (52 of 60). However, only myolysis and lipofuscin levels were found to be an independent histologic finding associated with the development of postoperative atrial fibrillation. Electron microscopy showed that myolytic vacuoles were not membrane bound, and were associated with lipofuscin deposits. Neither mitochondrial pathology nor apoptosis was detected in the atria before or after operation., Conclusions: Abnormalities in biopsies before cardiopulmonary bypass can indicate the susceptibility to develop postoperative atrial fibrillation. This implies that the status of the atrium before cardiopulmonary bypass is a major determinant in the development of this common complication.

Background and Aim of the Study: Thrombolysis is an emerging method to open thrombosed prosthetic heart valves. However, its applicability and safety in multiple recurrent thrombotic episodes is unclear., Methods: Among 16 patients with thrombosed prosthetic valves treated with thrombolysis during a 33-month period, three patients (one mitral and two tricuspid) experienced four episodes each, and these were treated with repeated thrombolytic therapy. Data on patient demographics, clinical presentation, diagnosis, treatment and outcome are presented., Results: Thrombolysis was successful in 10/12 episodes (83%); there was delayed response in one episode (8%), and partial response in one episode (8%). There were no major complications. However, a fifth thrombotic episode occurred in two patients with tricuspid prostheses, mandating re-do surgery., Conclusion: Thrombolysis in re-thrombosed prosthetic heart valves is feasible, highly successful and safe, and may therefore be used judiciously in selected patients who could not, or would not, undergo redo surgery. A high recurrence rate in the tricuspid position may implicate earlier surgical intervention, which should be individualized.

Postoperative atrial arrhythmias after cardiac surgical procedures are common, with a reported overall incidence of approximately 50%. The pathophysiological mechanisms responsible for atrial fibrillation after a cardiac procedure remain unclear, although several clinical studies published during the past decade have identified certain preoperative risk factors associated with postoperative atrial fibrillation. In this study, we attempted to identify the histopathological changes in atrial cardiomyocytes that might predict the development of atrial fibrillation during the postoperative period. Atrial tissue from 60 patients was sampled before and after a cardiopulmonary bypass. Fifteen patients (25%) developed postoperative atrial fibrillation. The only clinical independent risk factor for the development of postoperative atrial fibrillation was chronic obstructive pulmonary disease (COPD) (P = .037). Histologically, there were 3 findings in the atrial myocardium that were more common in patients who developed postoperative atrial fibrillation: (1) vacuolation size (P = .017), (2) vacuolation frequency (P = .0136), and (3) lipofuscin content (P = .013). The identification of these histological markers for the development of postoperative atrial fibrillation may contribute not only to our understanding of the underlying pathophysiology that leads to postoperative atrial fibrillation but also to a method of preventing this troublesome complication of cardiac surgery.

The use of cardiopulmonary bypass (CPB) in children is associated with significant morbidity due to the accumulation of an excessive amount of water. This can be decreased by massive diuresis, peritoneal dialysis, or conventional ultrafiltration technique (CUF) during bypass. However, we were dissatisfied with their effect on the outcome of our young patients, and recently began to use the modified technique of ultrafiltration (MUF) with good results. MUF was carried out for 15 min after completion of CPB to a hematocrit of 40%. Eighty patients were equally divided into two groups--MUF (group A) and control (group B)--and prospectively studied. There was one death in group A and two deaths in group B. The chest was left open in one patient in group A and in three patients in group B. At the end of MUF, the cardiac size was smaller, performance was better, and systemic blood pressure was higher in group A. Hematocrit levels in the two groups were similar during preoperative and CPB time, but post-CPB hematocrit in group A was significantly higher, 39.4% mean (range 35-50) vs. 28.5 (range 22-38) in group B (P <0.05). Blood loss was 10.56 ml/kg per 24 h (2-48.7) in group A vs. 20.8 (4.5-105.6) in group B (P <0.05). Blood transfused was 7.2 ml/kg per 24 h (0-29) in group A vs. 17.3 (3.1-49) in group B (P <0.05). Colloids transfused were 16.7 ml/kg per 24 h (0-64) in group A vs. 27.5 (0-58.6) in group B (P <0.05). No significant difference was found in urine output or the use of diuretics between the two groups. MUF results in better hemodynamic status in children, with the added advantage of less transfused blood and blood products. We believe that the use of accepted surgical techniques in combination with MUF will further improve the outcome of complex cardiac malformations.

Coronary artery stents were developed to prevent acute coronary closure and reduce restenosis after coronary angioplasty. A well-recognized, although uncommon, complication of stent deployment is loss of control, resulting in the stent being inadvertently deployed in an undesirable location. This case study describes a patient who underwent stent insertion to the left anterior descending artery and had stent entrapment in the left anterior descending/left main coronary artery. The stent was surgically removed, preventing unnecessary bypass grafting to a normal circumflex artery.

Acute mitral regurgitation due to ruptured chordae tendineae is a dramatic and life-threatening clinical situation. Rarely does this complication occur during pregnancy. We present a case of a 30-year-old woman in week 31 of her pregnancy who developed acute mitral regurgitation, secondary to bacterial endocarditis and ruptured chordae tendineae. This acute event resulted in preterm labor a few hours later. Delivery was uneventful and successful and was followed by open heart surgery 5 days later. A review of the literature on chordae tendineae rupture and resulting mitral regurgitation during pregnancy is presented.

Eleven patients underwent late repeated correction of tetralogy of Fallot in 1991-1993. The previous operation was repair of simple Fallot's tetralogy in seven cases, repair plus transannular patch in one case and repair of tetralogy and pulmonic atresia in three cases. The indications for reoperation were residual ventricular septal defect, right ventricular outflow tract (R.V.O.T.) obstraction, residual branch pulmonary artery stenosis, aneurysmal dilatation of R.V.O.T. Patch or combination of any of the above. At reoperation these defects were corrected. The post operative course was uneventful in eight patients. Two required mechanical ventilation for 2-3 days, and one underwent another operation for residual branch pulmonary artery stenosis. The functional and haemodynamic results were good in ten patients, and one had residual distal pulmonary artery stenosis. There were no death during 2 years of follow-up. Repeated correction of tetralogy of Fallot thus had low postoperative morbidity and good haemodynamic results. For the relatively few patients initially found to have tetralogy of Fallot and pulmonic atresia, the outcome may be less favorable.

Definitive repair of tetralogy of Fallot was performed on 104 children, including 42 younger than 2 years (24 < 1 year and 7 < 6 months). Twenty-two had previous shunt. Transannular patching was required in 60 cases and conduit grafts in two. During 60-day postoperative observation, five patients died. Of the 99 survivors, 93 recovered without complications, three required prolonged mechanical ventilation, two reoperation and one balloon dilatation for residual left pulmonary artery stenosis. Morbidity and mortality were not significantly higher in the patients younger than 12 months, although transannular patching was more common in that age group. Previous shunt operations entailed higher prevalence of distal stenosis and distortion of the pulmonary arteries, which often necessitated surgical repair, and also considerably increased postoperative morbidity and mortality. As the outcome in definitive repair of Fallot's tetralogy is favourable, even in patients younger than 12 months, and as preliminary shunt operations are associated with heightened perioperative morbidity and mortality rates in definitive repair, we advocate the definitive operation for all young patients with severe cyanosis or cyanotic spells.

We reviewed our experience with 40 patients who had undergone total cavopulmonary connection (TCPC) during the past three years. Thirty-one patients had functional single ventricle; only 8 of these with tricuspid atresia, five patients had complex forms of double outlet right ventricle (DORV), and four complex A-V canal. Previous palliative procedures, mostly systemic-pulmonic shunts, were performed in 34 patients. Concomitant procedures were required in 18 patients, mainly reconstruction of distorted pulmonary arteries. A subgroup of 14 high risk patients, that did not fulfil the classical Fontan criteria, underwent 4 mm fenestration of the intra-atrial baffle. There were three (7.5%) early postoperative deaths which occurred in the higher risk group (fenestrated group). However, the remaining patients were all in functional class I or II. Total cavopulmonary connection provides reasonably good definitive palliation for patients with single ventricle physiology. Fenestration of the intra-atrial baffle increases the number of candidates suitable for the Fontan procedure, although the exact inclusion criteria for these patients has yet to be defined.

We reviewed our experience with 40 patients who had undergone total cavopulmonary connection during the past 3 years. Thirty-one patients had functional single ventricle, only 8 with tricuspid atresia; five had complex forms of double outlet right ventricle, and 4 complex A-V canal. Previous palliative procedures, mostly systemic-pulmonic shunts, were performed in 34 patients. Concomitant procedures, mainly reconstruction of distorted pulmonary arteries, were required in 18 patients. A subgroup of 14 high risk patients, who did not fulfil the classical Fontan criteria, underwent 4 mm fenestration of the intraatrial baffle. There were 3 (7.5%) early post-operative deaths that occurred in the higher risk group (fenestrated group). However, the remaining patients were all in functional class I or II. Total cavopulmonary connection provides reasonably good definitive palliation for patients with single ventricle physiology. Fenestration of the intraatrial baffle increases the number of candidates suitable for the Fontan procedure, although the exact inclusion criteria for these patients has yet to be defined.

Left main pseudoaneurysm is a rare angiographic finding in young adults. We describe a 23-year-old male who presented with an acute anterior wall myocardial infarction. Coronary angiography and transesophageal echocardiography reveal a huge aneurysm of the distal left main obstructing the left anterior descending artery (LAD), which was defined by history as a pseudoaneurysm. The pseudoaneurysm was successfully resected and mammary artery was used to repair the distal left main and to bypass the LAD.

The prevalence of musculoskeletal system complaint and involvement in a group of 54 Crohn's disease patients, with a follow-up of 2 to 40 years, was studied and compared to that of a control group of patients with a similar distribution of sex and age. Twenty-four (44%) with Crohn's disease complained of arthralgia in various joints, but only 7.4% had objective findings compatible with joint pathology such as swelling, tenderness, and decreased range of motion. None of them had any serological or radiological evidences of joint damage. No significant correlation was found between patients' complaints/physical signs and age, sex, duration, or severity of Crohn's disease or mode of medical or surgical treatment. In the control group, 46% complained of arthralgia in various joint. The differences in the percentages of arthralgia between the two groups was not significant, although they differed in location of the affected joint. In the Crohn's disease group, a significantly higher proportion of knee, hip, and wrist involvement was observed, while backache was very common in the control group. It is suggested that arthritis in patients with Crohn's disease is an uncommon finding and that arthralgia is just as prevalent as in a matched control group. The pathogenesis of arthralgia in such a condition may be caused by soft tissue involvement.