Biomedical subjects

Alexander Kogan

Publications and source records attributed to Alexander Kogan.

11 recordsLinked to original sources

PubMed2007

Takotsubo cardiomyopathy: expanding the differential diagnosis in cardiothoracic surgery.

We describe a case of takotsubo cardiomyopathy in a 69-year-old woman after right upper lobectomy, without cardiac antecedents. The immediate course of recovery was uneventful. On the first postoperative day, clinical symptoms of acute coronary syndrome developed in association with ischemic electrocardiographic changes and a mild elevation in creatinine phosphokinase levels. Echocardiography showed moderate left ventricular dysfunction, with a typical takotsubo pattern. Coronary angiography revealed no abnormalities. After 2 days of supportive treatment, the patient recovered completely. The clinical presentation, instrumental findings, additional cardiac and noncardiac diseases, and the potential pathomechanism of takotsubo cardiomyopathy are described according to the current medical literature.

Aged↗

PubMed2006

Validation of the 2000 Bernstein-Parsonnet score versus the EuroSCORE as a prognostic tool in cardiac surgery.

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.

Aged↗

PubMed2006

Optimizing early extubation after coronary surgery.

Early extubation after isolated coronary artery bypass surgery was assessed retrospectively in 545 of 779 patients treated by the same surgical team over one year. All underwent extubation within 10 hr of arrival at the cardiothoracic intensive care unit: 343 in < 6 hr and 202 in 6-10 hr. Operative mortality was 2.2%. Group comparisons revealed that patients who had earlier extubation were younger (61 vs. 66 years; p < 0.001), more likely to be male (72.5% vs. 61.3%; p < 0.05), with a shorter aortic crossclamp time (49.2 +/- 15.0 vs. 53.3 +/- 14.0 min; p < 0.05), cardiopulmonary bypass time (65 +/- 18.4 vs. 72.2 +/- 19.2 min; p < 0.05), intensive care unit stay (18.8 +/- 5.6 vs. 22.4 +/- 3.2 hr; p < 0.05) and postoperative hospital stay (5.2 +/- 2.2 vs. 6.0 +/- 2.4 days; p = 0.01). Extubation < 6 hr after cardiopulmonary bypass may accelerate recovery. The finding of no significant differences in clinical parameters between the groups suggests that efforts to further reduce the time to extubation might be worthwhile.

Age Factors↗

PubMed2005

Multiple arterial revascularization using the tangential K-graft technique.

The tangential K graft is a comfortable surgical technique aiming to increase cardiac surgeons' versatility in performing multiple arterial grafting using only two arterial conduits. One end of the free graft--either the right internal thoracic artery (RITA) or the radial artery (RA)--is attached to a marginal circumflex branch. Its other end is anastomosed end to side to a diagonal branch. After the left internal thoracic artery (LITA) is attached to the left anterior descending coronary artery, a wide-open side-to-side LITA to free RITA or RA anastomosis--resembling the letter K--is constructed.

Aged↗

PubMed2005

Use of recombinant factor VII to control bleeding in a patient supported by right ventricular assist device after heart transplantation.

A 48-year-old man undergoing orthotopic heart transplantation for ischemic cardiomyopathy developed severe right heart failure. Severe intractable bleeding complicated implantation of a right ventricular assist device. Treatment with 9.6 mg of recombinant activated factor VII stopped the bleeding, and the patient could be transferred to the intensive care unit. This is the first reported case of the successful use of recombinant activated factor VII to control bleeding with subsequent right ventricular assist device function.

Cardiomyopathies↗

PubMed2004

Utilization of low-profile intra-aortic balloon catheters inserted by the sheathless technique in acute cardiac patients: clinical efficacy with a very low complication rate.

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.

Acute Disease↗

PubMed2004

Surgical reconstruction of the left main coronary artery: fresh autologous pericardium or saphenous vein patch.

BACKGROUND: Isolated stenosis of the left main coronary artery is usually treated by coronary bypass surgery. However, this approach restores a less physiologic perfusion of the myocardium that leads to occlusion of the left main coronary artery, and restores only a retrograde perfusion of a rather extensive myocardial area. Coronary ostial plasty has been described as an alternative surgical technique in isolated ostial left main coronary artery stenosis without calcification. We review our experience with 15 patients. METHODS: After placing the patient on cardiopulmonary bypass and aortic cross clamping, the main pulmonary trunk was retracted laterally. The left main coronary artery was approached anteriorly through a curved aortotomy. Reconstruction was performed using fresh pericardial patch or saphenous vein that was tailored as a patch. RESULTS: There were no early mortality or perioperative myocardial infarctions. During mean follow-up of 55 +/- 39 months, no patients had any cardiac events or required repeated coronary intervention. All patients underwent follow-up transesophageal echocardiography, which demonstrated a wide open left main coronary artery (range 3 to 8 mm), normal flow pattern by pulsed-wave Doppler, and no aneurysmal dilatation or calcification of the onlay patch. Coronary angiography and intravascular ultrasound were performed in 2 patients because of nonspecific chest discomfort. In both cases, the left main coronary artery was found to be wide open, and there were no signs of patch calcification. CONCLUSIONS: Surgical reconstruction of the left main coronary artery is safe and effective for the treatment of selected cases of isolated left main stenosis. The use of autologous pericardium appears to be as safe as saphenous vein patch. Neither method was associated with postoperative aneurysmal dilatation or calcification.

Aged↗

PubMed2003

Readmission to the intensive care unit after "fast-track" cardiac surgery: risk factors and outcomes.

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.

Adult↗

PubMed2003

Propofol-ketamine mixture for anesthesia in pediatric patients undergoing cardiac catheterization.

OBJECTIVE: To evaluate the safety of a propofol-ketamine mixture to induce and maintain anesthesia in spontaneously breathing pediatric patents during cardiac catheterization. DESIGN: Prospective clinical study. SETTING: Departments of Cardiothoracic Surgery, Anesthesiology, and Pediatric Anesthesiology in a university hospital. PARTICIPANTS: Forty-five children aged 6 months to 16 years with ASA grade II to III undergoing cardiac catheterization. INTERVENTIONS: Continuous intravenous infusion of a mixture of propofol (4 mg/mL) and ketamine (2 mg/mL) with spontaneous ventilation. The infusion rate was changed and additional boluses of propofol or/and ketamine were given as needed. Hemodynamic, respiratory, and other variables were recorded during the procedure and recovery. RESULTS: Mean dose of ketamine was 26 +/- 8.3 microg/kg/min and of propofol, 68.3 +/- 21.7 microg/kg/min. Changes in heart rate and mean arterial pressure of more than 20% from baseline were observed in 4 and 5 patients, respectively. A transient reduction in oxygen saturation because of hypoventilation was observed in 3 patients and responded to oxygen administration and manual assisted ventilation. No other complications were observed. CONCLUSIONS: The propofol-ketamine mixture is a safe, practical alternative for general anesthesia in pediatric patients undergoing cardiac catheterization.

Adolescent↗

PubMed2002

Premedication with midazolam in young children: a comparison of four routes of administration.

BACKGROUND: We undertook a study to determine the effects of four routes of administation on the efficacy of midazolam for premedication. METHODS: In a randomized double-blind study, 119 unmedicated children, ASA I-II, aged 1.5-5 years, who were scheduled for minor elective surgery and who had been planned to received midazolam as a premedicant drug, were randomly assigned to one of four groups. Group I received intranasal midazolam 0.3 mg.kg-1; group II, oral midazolam 0.5 mg x kg(-1); group III, rectal midazolam 0.5 mg x kg(-1); and group IV, sublingual midazolam 0.3 mg x kg(-1). A blinded observer assessed the children for sedation and anxiolysis every 5 min prior to surgery. Quality of mask acceptance for induction, postanaesthesia care unit behaviour and parents' satisfaction were evaluated. Thirty patients were enrolled in each of groups I, III and IV. Twenty-nine patients were enrolled in group II. RESULTS: There were no significant differences in sedation and anxiety levels among the four groups. Average sedation and anxiolysis increased with time, achieving a maximum at 20 min in group I and at 30 min in groups II-IV. Patient mask acceptance was good for more than 75% of the children. Although the intranasal route provides a faster effect, it causes significant nasal irritation. Seventy-seven percent of the children from this group cried after drug administration. Most parents in all groups (67-73%) were satisfied with the premedication. CONCLUSIONS: Intranasal, oral, rectal and sublingual midazolam produces good levels of sedation and anxiolysis. Mask acceptance for inhalation induction was easy in the majority of children, irrespective of the route of drug administration.

Anesthesia Recovery Period↗

PubMedDate not supplied

Informatics in radiology (infoRAD): integrating MIRC-compliant semiautomated teaching files into PACS work flow.

A Medical Image Resource Center (MIRC)-compliant teaching file system was created that can be integrated into a picture archiving and communication system (PACS) environment. This system models the three-step process necessary for efficient teaching file creation in a PACS environment: (a) identifying and transferring a case quickly and easily during primary interpretation, (b) editing and authoring the case outside of primary interpretation time, and (c) publishing the case locally and via MIRC standard-based mechanisms. Images from interesting cases are e-mailed to the teaching file system from either the PACS workstation or the radiologist's personal computer. Notes and clinical information may be included in the e-mail text to prompt the recollection of case details. Images are automatically extracted from the e-mail and sent to an image repository, and text fields are captured in a database. The World Wide Web-based authoring component provides tools for final authoring of cases and for the manipulation of existing cases. Authors designate access levels for each case, which is then made available locally and, potentially, to the entire MIRC-compliant community. Although this application has not yet been implemented as a departmental solution, it promises to improve and streamline medical education and promote better patient care.

Radiology↗