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The installation of Distributed Generation (DG) units in the Radial Distribution Networks (RDNs) has significant potential to minimize active power losses in distribution networks. However, inaccurate size(s) and location(s) of DG units increase power losses and associated Annual Financial Losses (AFL). A comprehensive review of the literature reveals that existing analytical, metaheuristic and hybrid algorithms employed on DG allocation problems trap in local or global optima resulting in higher power losses. To address these limitations, this article develops a parallel hybrid Arithmetic Optimization Algorithm and Salp Swarm Algorithm (AOASSA) for the optimal sizing and placement of DGs in the RDNs. The proposed parallel hybrid AOASSA enables the mutual benefit of both algorithms, i.e., the exploration capability of the SSA and the exploitation capability of the AOA. The performance of the proposed algorithm has been analyzed against the hybrid Arithmetic Optimization Algorithm Particle Swarm Optimization (AOAPSO), Salp Swarm Algorithm Particle Swarm Optimization (SSAPSO), standard AOA, SSA, and Particle Swarm Optimization (PSO) algorithms. The results obtained reveals that the proposed algorithm produces quality solutions and minimum power losses in RDNs. The Power Loss Reduction (PLR) obtained with the proposed algorithm has also been validated against recent analytical, metaheuristic and hybrid optimization algorithms with the help of three cases based on the number of DG units allocated. Using the proposed algorithm, the PLR and associated AFL reduction of the 33-bus and 69-bus RDNs improved to 65.51% and 69.14%, respectively. This study will help the local distribution companies to minimize power losses and associated AFL in the long-term planning paradigm., Competing Interests: The authors have declared that no competing interests exist.

Objective: to estimate the association between preoperative hemoglobin A1c (HbA1c) levels below and above 7%, and the rate of all-cause mortality (ACM) in diabetes mellitus (DM) patients after coronary artery bypass grafting (CABG) within a ten-year follow-up period., Methods: we collected data on patient HbA1c levels that were measured up to 3 months prior to isolated CABG in consecutive patients with DM, and analyzed the rates of ACM over a median of a 5.9-year post-operative period., Results: preoperative HbA1c levels were collected in 579 DM patients. The mean HbA1c was 8.0 ± 1.7%, where 206 (35.6%) patients had an HbA1c ≤ 7% and 373 (64.4%) had an HbA1c > 7%. During the follow-up period, mortality rates were 20.4% and 28.7% in the HbA1c ≤ 7% and HbA1c > 7% groups, respectively (Kaplan-Meier estimates, log-rank p = 0.01). Multivariable Cox proportional hazards regression, adjusted for age, gender, smoking status, chronic obstructive pulmonary disease, hypertension, chronic renal failure, old myocardial infarction, number of coronary artery bypass surgeries, and post-operative glycemic control, showed a hazard ratio of 2.67 for long-term ACM ( p = 0.001) in patients with HbA1c > 7%., Conclusions: DM patients with high HbA1c levels prior to CABG are at higher risk for long-term complications, especially late ACM.

Background: Practice guidelines emphasize the role of the SYNTAX score (SS; Synergy Between PCI With TAXUS and Cardiac Surgery) in choosing between percutaneous coronary intervention and coronary artery bypass graft surgery in cases of complex coronary artery disease. There is paucity of data on the implementation of these recommendations in daily practice, and on the consequences of guideline discordant revascularization., Methods: This was a retrospective analysis of a prospective national survey of consecutive real world patients undergoing coronary revascularization for complex coronary artery disease according to decisions of local heart team at each center. SS was calculated at a dedicated CoreLab, and patients were classified as heart team/guidelines agreement/discordant., Results: Nine hundred seventy-nine patients (571 percutaneous coronary intervention and 408 coronary artery bypass graft) were included. Mean age was 65 years and the mean SS was 22. Heart team/guidelines discordance occurred in 170 (17.3%) patients. Independent predictors of heart team/guidelines discordance were age, admission to a center with no cardiac surgery service, SS, and previous percutaneous coronary intervention/myocardial infarction. A multivariate model based on these characteristics had a C statistic of 0.83. Thirty-day outcomes were similar in the agreement/discordance groups, however, heart team/guidelines discordance was associated with a significant increase in 3 year mortality (17.6% versus 8.4%; hazard ratio, 2.05; P =0.002) after multivariate adjustment., Conclusions: Heart team/guidelines discordance is not infrequent in real world patients with complex coronary artery disease undergoing revascularization. This is more likely to occur in elderly patients, those with more complex coronary disease (as determined by the SS), and those treated at centers with no cardiac surgery service. These patients have a higher risk for mid-term mortality.

Background: We sought to assess real-world implementation of the guidelines in patients with multivessel coronary artery disease (CAD) using a prospective national registry in Israel., Methods: All consecutive patients with left main or 2- to 3-vessel CAD involving the proximal or mid left anterior descending artery were enrolled in a dedicated multicenter registry. Patients were managed at the discretion of the treating team at each hospital and were followed for 30 months., Results: This registry included 1,064 patients, 55% treated with percutaneous coronary intervention (PCI) and 45% with coronary artery bypass surgery (CABG). Multivariate logistic regression analysis showed that chronic renal failure (odds ratio [OR], 2.43; p = 0.001) and prior myocardial infarction (OR, 1.7; p = 0.024) were associated with referral to PCI versus CABG, whereas male gender (OR, 2.27; p < 0.001), prior aspirin treatment (OR, 1.72; p = 0.005), diabetes mellitus (OR, 1.51; p = 0.007), 3-vessel CAD (OR, 3.45; p < 0.001) and SYNTAX score (SS) greater than 32 (OR, 10.0; p < 0.001) were associated with referral to CABG versus PCI. Each point increment in the SS was independently associated with a 9% greater likelihood of referral to CABG (p < 0.001). Survival analysis showed that mortality risk was lower among PCI patients less than 8 months after the procedure, and CABG was associated with a significant survival benefit thereafter., Conclusions: We found good agreement with current guidelines regarding revascularization strategies in real-world patients with multivessel CAD. The SS was the main independent predictor associated with the choice of revascularization strategy. The time-dependent association between revascularization strategy and long-term survival should be incorporated in the risk assessment of this population., (Copyright © 2019 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Cardiopulmonary bypass (CPB) elicits a systemic inflammatory response that may impair blood-brain barrier (BBB) integrity. BBB disruption can currently be detected by dynamic contrast enhancement magnetic resonance imaging (MRI), reflected by an increase in the permeability constant (K trans ). We aimed to determine (1) whether CPB induces BBB disruption, (2) duration until BBB disruption resolution, and (3) the obtainable correlation between BBB injury (location and intensity) and neurocognitive dysfunction., Methods: Seven patients undergoing CPB with coronary artery bypass grafting (CABG) were assigned to serial cerebral designated MRI evaluations, preoperatively and on postoperative day (POD) 1 and 5. Examinations were analyzed for BBB disruption and microemboli using dynamic contrast enhancement MRI and diffusion-weighted imaging methods, respectively. Neuropsychologic tests were performed 1 day preoperatively and on POD 5., Results: A significant local K trans increase (0.03 min -1 vs 0.07 min -1 , p = 0.033) compatible with BBB disruption was evident in 5 patients (71%) on POD 1. Resolution was observed by POD 5 (mean, 0.012 min -1 ). The location of the disruption was most prominent in the frontal lobes (400% vs 150% K trans levels upsurge, p = 0.05). MRI evidence of microembolization was demonstrated in only 1 patient (14%). The postoperative global cognitive score was reduced in all patients (98.2 ± 12 vs 95.1 ± 11, p = 0.032), predominantly in executive and attention (frontal lobe-related) functions (91.8 ± 13 vs 86.9 ± 12, p = 0.042). The intensity of the dynamic contrast enhancement MRI BBB impairment correlated with the magnitude of cognition reduction (r = 0.69, p = 0.04)., Conclusions: BBB disruption was evident in most patients, primarily in the frontal lobes. The location and intensity of the BBB disruption, rather than the microembolic load, correlated with postoperative neurocognitive dysfunction., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Atrial fibrillation (AF) is a common complication of coronary artery bypass graft (CABG) surgery, occurring in 20%-40% of patients, mostly during the first week after surgery. It is associated with increased morbidity and mortality, but data are limited., Objectives: To assess the correlation between new-onset in-hospital AF following CABG and long-term AF, cerebrovascular accident (CVA), or death., Methods: We conducted an analysis of 161 consecutive patients who underwent isolated CABG surgery in a tertiary center during the period 2002-2003., Results: Patients' mean age was 72 years, and the majority were males (77%). Approximately half of the patients experienced prior myocardial infarction, and 14% had left ventricular ejection fraction < 40%. Postoperative AF (POAF) occurred in 27% of the patients. Patients were older and had larger left atrium diameter. POAF was strongly correlated with late AF (OR 4.34, 95%CI 1.44-13.1, P = 0.01) during a mean follow-up of 8.5 years. It was also correlated with long-term stroke but was not associated with long-term mortality., Conclusions: POAF is a common complication of CABG surgery, which is correlated with late AF and stroke. Patients with POAF should be closely monitored to facilitate early administration of anticoagulant therapy in a high risk population upon recurrence of AF.

Training the next generation of cardiothoracic surgeons is a global persistent challenge. Major issues, including length of training, decreasing volume of cases, shift toward high-risk, complex, and less-invasive procedures, increased specialization, and uncertainty with regard to future employment, are relevant and affect residency training programs in the United States, Europe, and other parts of the world. To produce high-quality, mature, and qualified surgeons, these challenges mandate an ongoing effort by our specialty leadership aimed at identifying creative solutions and adapting the current residency training curricula and methodology to the dynamic changes in our field. The current situation in Israel is discussed with the hope that sharing our experience might be useful and lead to adoption of some of our solutions by other countries., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: We compared the flow rates, reactivity, and morphology of the distal internal thoracic artery and its branches, the superior epigastric and musculophrenic arteries, to test their applicability as possible conduits in coronary artery bypass grafting surgeries., Methods: Skeletonized internal thoracic artery and subdivisions of patients undergoing coronary artery bypass grafting were studied intraoperatively (n = 100) for flow and length measurements and in vitro in organ baths (n = 58) for active response to norepinephrine. Quantitative microscopic analysis of the muscle density and degree of intimal hyperplasia was performed. Results were analyzed according to age, gender, risk factors, and medications., Results: Internal thoracic artery subdivisions contributed an average extra length of 2 cm. Free flow rates were 129 ± 45 mL/min, 114 ± 41 mL/min, and 93 ± 36 mL/min in the internal thoracic artery, superior epigastric artery, and musculophrenic artery, respectively. Sternum and internal thoracic artery length and free flow rates were significantly lower in women. The subdivisions were significantly more reactive to norepinephrine than the distal internal thoracic artery (P ∼ .005), although sensitivity to norepinephrine was similar. Patients treated with beta-blockers had significantly decreased reactivity (P = .009). Microscopic analysis suggests similar muscle content in the internal thoracic artery and subdivisions. Eccentric (28%) and concentric (62%) intimal hyperplasia were observed in 90% of specimens, with no evidence for atherosclerotic plaques. There was no significant difference in the degree of intimal hyperplasia between the distal internal thoracic artery and its subdivisions, and there was no correlation to risk factors., Conclusions: Our results confirm the previous studies on the higher contractility in internal thoracic artery subdivisions, suggesting caution in the use of the bifurcation for revascularization. However, the extra length, sufficient flow, and favorable histologic properties suggest that the bifurcation may be appropriate for coronary revascularization in selected cases., (Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Talcosis due to intravenous injection of oral drugs can cause severe pulmonary disease with progressive dyspnea even when drug use is discontinued. We describe a 54-year-old woman with severe emphysema who underwent left lung transplantation. The patient had a remote history of intravenous injection of crushed methylphenidate (Ritalin) tablets. Chest computed tomography showed severe emphysematous changes, more prominent in the lower lobes. Microscopic examination of the extracted lung demonstrated multinucleated giant cells with birefringent crystals, compatible with talcosis. At follow-up, daily symptoms were completely alleviated and lung function was good. We recommend that lung transplantation be considered as a viable option in the treatment of talcosis.

Background: [corrected] The use of intraoperative transesophageal echocardiogram in patients with infective endocarditis is usually reserved for cases of inadequate preoperative testing or suspected extension to perivalvular tissue., Objectives: To explore the impact of routine intraoperative TEE in patients with infective endocarditis., Methods: The impact of intraoperative TEE on the operative plan, anatomic-physiologic results, and hemodynamic assessment or de-airing was analyzed in 59 patients (38 males, 21 females, mean age 57.7 +/- 16.8 years, range 20-82) operated for active infective endocarditis over 56 months., Results: Immediate pre-pump echocardiography was available in 52 operations (86.7%), and changed the operative plan in 6 of them (11.5%). Immediate post-pump study was available in 59 patients (98.3%) and accounted for second pump-run in 6 (10.2%): perivalvular leak (3 cases), and immobilized leaflet, significant mitral regurgitation following vegetectomy, and failing right ventricle requiring addition of vein graft (1 case each). Prolonged de-airing was necessary in 6 patients (10.2%). In 5 patients (8.5%) the postoperative study aided in the evaluation and treatment of difficult weaning from the cardiopulmonary bypass pump. In 21 patients (35.6%) the application of intraoperative TEE affected at least one of the four pre-specified parameters., Conclusions: Intraoperative TEE has an important role in surgery for infective endocarditis and should be routinely implemented.

There are known clinical and laboratory predictors for stroke and death following CABG. The aim of this study was to determine if transthoracic echocardiographic findings prior to CABG have additional predictive value for occurrence of perioperative cerebrovascular accident (CVA) and death. The files of patients who underwent CABG between January 2002 and November 2004, with perioperative echocardiographic assessment were reviewed. Echocardiographic variables examined included LV size, function and hypertrophy, mitral annulus calcification (MAC) and aortic valve calcification (AVC). Patients in whom post-CABG stroke or death was documented were compared with those without these endpoints. Of the 572 patients who met the study criteria, 33 (5.8%) had a neurological event and 26 (4.5%) died, four after a major stroke. One hundred and sixty-seven patients had MAC and 228 AVC. On multivariate analysis, risk factors for stroke were previous stroke (OR=2.91 CI 1.179-7.24; P<0.005), renal failure (OR=2.48 CI 1.039-5.95; P<0.001) and older age (OR=1.60 CI 0.971-2.63; P<0.001); risk factors for death were perioperative insertion of intra-aortic balloon pump (OR=33.7 CI 11.38-100; P<0.001) and peripheral vascular disease (OR=3.89 CI 1.32-11.45; P<0.001). Medically treated dyslipidemia was protective factor. LV hypertrophy significantly predicts stroke post-CABG by univariate analysis (P=0.02). There was no significant correlation between AVC and MAC with stroke, although death was slightly increased in patients with MAC (44% vs. 29.2%, P=0.114).

Background: Lung transplantation is a well-established therapeutic option for end-stage lung disease in cystic fibrosis. Although it confers a clear survival advantage, outcome differs among centers according to local experience, patient selection, transplantation procedure, and postoperative care., Objectives: To evaluate the national Israeli experience with lung transplantation in patients with CF., Methods: We reviewed the medical charts of all CF patients who underwent lung transplantation between January 1996 and June 2005 at the two Israeli centers that perform this procedure., Results: Eighteen transplantations were performed in 17 patients. Mean patient age at transplantation was 25.3 +/- 9.1 years, and mean duration of follow-up in survivors (n=14) was 37.2 months (range 1-113 months). The actuarial survival rate was 88% at 1 year and 74% at 5 years. Pulmonary function, expressed as percent of predicted normal forced expiratory volume in 1 sec, improved from 22.4 +/- 8.1% to 76 +/- 16.8% at one year after transplantation. Bronchiolitis obliterans syndrome was diagnosed in 5 patients (29%), of whom 2 died and 2 are currently candidates for retransplantation. Median time to onset of BOS was 34.2 months (range 17-64 months)., Conclusion: In Israel, the early and intermediate-term results of lung transplantation for cystic fibrosis are encouraging. BOS remains a major complication that threatens long-term outcome.

Background: Right-heart-catheterization and transthoracic echocardiography are routine tests to measure pulmonary artery systolic pressure among lung transplantation candidates. Echocardiography may be as accurate as right-heart-catheterization, without the inherent risks of an invasive test., Methods: We examined the correlation between pulmonary pressures estimated by echocardiography versus right-heart-catheterization among lung transplantation candidates and their correlation to measurements during lung transplantation. Our cohort included all lung transplantation candidates during 1997 through 2004 who initially underwent pulmonary pressure evaluation by right-heart-catheterization and echocardiography, as well as measurements during lung transplantation., Results: Of the 106 candidates, evaluation by transthoracic echocardiography was possible in 79 (74.5%). Median pulmonary systolic pressures by right-heart-catheterization was 44.0 [33.2-50.0] mm Hg and by echocardiography 40.0 [32.5-51.5] mm Hg (r = 0.80, p < 0.0001). In 14 (17.7%) patients the difference between the 2 methods was > 20 mm Hg. The median time interval between echocardiography and right-heart-catheterization was 65 [40-155] days. The median value of pulmonary systolic pressure measured during lung transplantation in 44 (70.1%) of 62 patients was 39.5 [31.0-50.0] mm Hg. The time interval right-heart-catheterization-to-lung transplantation was 143 [87-339] days and echocardiography-to-lung transplantation 229 [130-367] days. The correlation between measurements during lung transplantation and initial measurements by right-heart-catheterization and echocardiography were r = 0.50 and r = 0.31, respectively, with corresponding p values of p = 0.001 and p = 0.07., Conclusions: For lung transplantation candidates and a suitable transthoracic echocardiography estimate of pulmonary systolic pressure, the need for right-heart catheterization, with its inherent risks for complications, may be foregone. The weak correlation between the initial and intraoperative measurements, probably stemming from the significant time interval, suggests that serial measurements may be needed.

The shortage of organs for lung transplantation has led to the growing use of "marginal" donors. Although patients on hemodialysis are still excluded as lung transplant donors because of the possible effects of renal failure on the lungs, recent data suggest that they may be suitable in selected cases. This article describes the successful transplantation of two lungs from a single donor who had been receiving long-term hemodialysis treatment. In the absence of other causes of pulmonary diseases, such as smoking or lung infection, lungs from dialysis-dependent patients may be acceptable for lung transplantation.

Background: Intradepartmental and interdepartmental benchmarking requires scoring systems with reliability (calibration) and stability over the complete spectrum of periprocedural risk. The aim of this single-center study was to assess the performance of the 2000 Bernstein-Parsonnet risk stratification model in cardiac surgery, by itself and against the EuroSCORE., Methods: A prospective observational design was used. The study group consisted of 1,639 consecutive patients of mean age 64.6 +/- 12.04 years who underwent elective or emergency cardiac surgery from January 2003 to June 2004. The probabilities of hospital death were estimated with the 2000 Bernstein-Parsonnet and EuroSCORE algorithms. The correlation of predicted and observed mortality was compared between the two models, and score validity was assessed by calculating the area under the receiver operating characteristic (ROC) curve., Results: The patients were stratified into five risk groups according to their scores in the two models. For the 2000 Bernstein-Parsonnet model, findings were as follows: score 0-10: predicted mortality 0%-2.2%, observed mortality 0.6%; score 10.5-20: predicted 2.3%-4.7%, observed 2.3%; score 20.5-30: predicted 4.8%-10%, observed 6.7%; score 30.5-40: predicted 10.1%-23%, observed 11.5%; and score greater than 40: predicted 23.1%-80%, observed 29.9%. For the EuroSCORE, findings were as follows: score 0%-2%: predicted mortality 1.1%, observed mortality 0.6%; score 3%-5%: predicted 2.1%, observed 3.0%; score 6%-8%: predicted 4.1%, observed 3.5%; score 9-11: predicted 7.6%, observed 6.6.%; and score greater than 12: predicted 13.8%, observed 14.0%. There was good agreement between the observed and expected number of deaths, with both models. The area under the ROC curve was higher for the Bernstein-Parsonnet model (0.83, odds ratio [OR] 2.01, 95% confidence interval [CI] 1.75-2.31, p < 0.0001) than for the EuroSCORE (0.73, OR 1.05, 95% CI 1.04-1.07, p < 0.001)., Conclusions: The 2000 Bernstein-Parsonnet model is a simple, objective system for the estimation of hospital mortality in patients undergoing cardiac surgery, with slightly higher calibration and discrimination than the EuroSCORE additive model.

Objective: Several studies have recently reported an association between aortic valve calcification and atherosclerosis of the cardiovascular system, suggesting that aortic valve calcification might represent an atherosclerosis-like process. Hence the aim of the present study was to determine whether there is a similar association between aortic stenosis and aortic atheromas., Methods: We evaluated the records and echocardiographic videotapes of 91 consecutive patients with severe aortic stenosis who underwent intraoperative transesophageal echocardiography before aortic valve replacement to measure the presence and characteristics of aortic atheromas. There were 50 men (55%) and 41 women (45%). The mean age was 71.9 +/- 9.4 years (range, 34-91 years). These patients were compared with 91 sex-and age-matched patients without aortic stenosis who underwent transesophageal echocardiography for various indications. Aortic atheroma was defined as localized intimal thickening of 3 mm or larger. A lesion was considered complex if there was a plaque extending 5 mm or more into the aortic lumen; if the lesion was protruding, mobile, or ulcerated; or both., Results: The aortic stenosis group had significantly higher rates of aortic atheromas (85% vs 37%, P < .001) and complex atheromas (47% vs 9%, P < .001) compared with the control group. In the vast majority of patients in the aortic stenosis group, the aortic atheromas were localized in the aortic arch (60 [66%] patients, with 50% being complex aortic atheromas) and in the descending aorta (70 [77%] patients, with 45.7% being complex aortic atheromas); in only 4 (4.4%) patients, the aortic atheromas were localized in the ascending aorta (50% complex aortic atheromas)., Conclusions: There is a strong association between the presence of severe aortic stenosis and the presence and severity of aortic atheromas, suggesting that aortic stenosis might be a manifestation of the atherosclerotic process. These findings imply that (1) aggressive atherosclerotic risk-factor modification for patients with aortic stenosis might be advisable and (2) consideration of evaluation of the aorta by means of transesophageal echocardiography before aortic valve replacement in selected patients might be helpful.

Unlabelled: Initial intra-aortic balloon pump (IABP) catheters were of large caliber and their utilization resulted in a high incidence of complications, including limb ischemia, bleeding and thrombosis, peripheral neurologic sequelae, and infection. Despite eventual decrease in the size of IABP catheters, the complication rate has remained high., Hypothesis: The study was undertaken to determine whether use of recently available low-profile IABP catheters would result in a lower incidence of vascular and bleeding complications., Methods: We prospectively evaluated the incidence of complications when consecutively using the low-profile (8F) IABP catheter inserted mostly sheathlessly in 161 acute cardiac patients between January 1, 2000 and April, 2003., Results: Complications encountered included mild transient limb ischemia in two patients (1.2%), minor bleeding episodes in four patients (2.4%), one major puncture site bleeding (0.6%), and a pseudoaneurysm treated percutaneously in two patients (1.2%). Two patients (1.2%) suffered limb ischemia due to embolization or local thrombosis requiring vascular intervention. These complications were milder and their incidence remarkably lower than those reported previously when IABP catheters larger than 8F were used., Conclusion: Utilization of low-profile IABP 8F catheters in a sheathless technique entails an exceedingly low complication rate despite an acute presentation, intense anticoagulant and antiaggregant therapy, frequent comorbidity, advanced age, severe coronary disease, and reduced cardiac function in a large proportion of treated patients.

Objective: Significant hypophosphatemia (SH) is common after major surgery and may be associated with considerable morbidity, including respiratory and cardiac failure. The contribution of SH to these complications after cardiac surgery is not well defined., Methods: In this prospective study, levels of serum phosphorus and other electrolytes (potassium, magnesium and calcium) were measured in 566 consecutive patients (395 men, 182 women; mean age 65.5+/-11.1 years) undergoing elective cardiac surgery at three time points: prior to surgery, immediately on admission to the ICU, and on the first postoperative day. Preoperative (type of surgery, Bernstein-Parsonnet risk estimate), intraoperative (duration of bypass and cross-clamp, intraoperative fluid and blood product use) and postoperative data (duration of ventilation, duration of ICU and hospital stay, requirement for cardioactive drug support, development of atrial fibrillation, and mortality) were collected. Patients were divided into two groups according to the immediate postoperative phosphate level: SH, phosphate <0.48 mmol/l (mean phosphate 0.28+/-0.13 mmol/l, n = 194), and a control group (mean phosphate value 0.84+/-0.08 mmol/l, n = 372). Patients with SH received treatment with sodium or potassium phosphate (0.8 mmol/kg body weight over 6-12 h)., Results: SH was present in 34.3% of patients. There were no differences in the baseline characteristics between the two groups. Patients with SH received more intraoperative blood product transfusions. The postoperative course of patients with SH was characterized by prolonged ventilation (2.1+/-1.7 versus 1.1+/-0.9 days, P = 0.05), more patients requiring cardioactive drugs (12-24 h 16 versus 10.9%, P = 0.05 and >24 h 23.5 versus 13.8%, P = 0.05); and a prolonged hospital stay (7.8+/-3.4 versus 5.6+/-2.5 days, P = 0.05)., Conclusions: SH was common after open-heart surgery and was associated with an increased incidence of important complications. We suggest that phosphate levels be routinely measured immediately after surgery and appropriate therapy instituted.

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: The introduction of "fast-track" management into cardiac surgery has significantly shortened the intensive care unit (ICU) length of stay. Readmission to the ICU, traditionally used as a quality index, has not been investigated in these patients. The aim of this study was to assess the causes, risk factors, and outcomes associated with readmission to the ICU., Methods: All patients undergoing open-heart surgery in a tertiary care, university-affiliated center were included in this prospective observational study. Preoperative and intraoperative data as well as ICU outcome were noted in all patients., Results: Over the 27-month study period,1,613 patients were targeted for fast track management (discharge from ICU on the first postoperative day). The readmission rate was 3.29% (53 patients). Forty-three percent of readmissions occurred within 24 hours of discharge usually because of pulmonary problems (43%) or arrhythmias (13%). Readmission was associated with a prolonged ICU stay (105 +/- 180.0 versus 19.2 +/- 2.4 hours of initial ICU stay) and worse outcome: the only patients who died (6 of 53, 11.3%) were in this group. On multivariate analysis, a Bernstein-Parsonnet risk estimate more than 20 strongly predicted readmission (odds ratio, 3.08; 95% confidence interval, 1.43 to 6.69)., Conclusions: Among a homogeneous group of patients targeted for fast-track management after cardiac surgery, readmission although uncommon is associated with a longer second ICU stay and significant mortality. The recognition of specific risk factors may allow for appropriate modification of the postoperative course.

Human L-type voltage-dependent Ca(2+) channels (alpha(1C), or Ca(v)1.2) are up-regulated by protein kinase C (PKC) in native tissues, but in heterologous systems this modulation is absent. In rat and rabbit, alpha(1C) has two N-terminal (NT) isoforms, long and short, with variable initial segments of 46 and 16 amino acids, respectively. The initial 46 amino acids of the long-NT alpha(1C) are crucial for PKC regulation. However, only a short-NT human alpha(1C) is known. We assumed that a long-NT isoform of human alpha(1C) may exist. By homology screening of human genomic DNA, we identified a stretch (termed exon 1a) highly homologous to rabbit long-NT, separated from the next known exon of alpha(1C) (exon 1b, which encodes the alternative, short-NT) by an approximately 80 kb-long intron. The predicted 46-amino acid protein sequence is highly homologous to rabbit long-NT. Reverse transcriptase PCR showed the presence of exon 1a transcript in human cardiac RNA. Expression of human long-NT alpha(1C) in Xenopus oocytes produced Ca(2+) channel enhanced by a PKC activator, whereas the short-NT alpha(1C) was inhibited. The long-NT isoform may be the Ca(2+) channel enhanced by PKC-activating transmitters in human tissues.

Objectives: The present study evaluates the long-term course of aortic valve disease and the need for aortic valve surgery in patients with rheumatic mitral valve disease who underwent mitral valve surgery., Background: Little is known about the natural history of aortic valve disease in patients undergoing mitral valve surgery for rheumatic mitral valve disease. In addition there is no firm policy regarding the appropriate treatment of mild aortic valve disease while replacing the mitral valve., Methods: One-hundred thirty-one patients (44 male, 87 female; mean age 61+/-13 yr, range 35 to 89) were followed after mitral valve surgery for a mean period of 13+/-7 years. All patients had rheumatic heart disease. Aortic valve function was assessed preoperatively by cardiac catheterization and during follow-up by transthoracic echocardiography., Results: At the time of mitral valve surgery, 59 patients (45%) had mild aortic valve disease: 7 (5%) aortic stenosis (AS), 58 (44%) aortic regurgitation (AR). At the end of follow-up, 96 patients (73%) had aortic valve disease: 33 AS (mild or moderate except in two cases) and 90 AR (mild or moderate except in one case). Among patients without aortic valve disease at the time of the mitral valve surgery, only three patients developed significant aortic valve disease after 25 years of follow-up procedures. Disease progression was noted in three of the seven patients with AS (2 to severe) and in six of the fifty eight with AR (1 to severe). Fifty two (90%) with mild AR remained stable after a mean follow-up period of 16 years. In only three patients (2%) the aortic valve disease progressed significantly after 9, 17 and 22 years. In only six patients of the entire cohort (5%), aortic valve replacement was needed after a mean period of 21 years (range 15 to 33). In four of them the primary indication for the second surgery was dysfunction of the prosthetic mitral valve., Conclusions: Our findings indicate that, among patients with rheumatic heart disease, a considerable number of patients have mild aortic valve disease at the time of mitral valve surgery. Yet most do not progress to severe disease, and aortic valve replacement is rarely needed after a long follow-up period. Thus, prophylactic valve replacement is not indicated in these cases.