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B Levenson

Publications and source records attributed to B Levenson.

At least 19 recordsLinked to original sources

Contrast-enhanced adenosine-stress magnetic resonance imaging--feasibility and practicability of a protocol for detection or exclusion of ischemic heart disease in an outpatient setting.

BACKGROUND: Evaluating myocardial function, assessing ischemic myocardial areas and detecting myocardial viability are necessary diagnostic information for guiding further therapy in patients with angina. The aim of this study was to show feasibility and safety of a compiled contrast- enhanced magnetic resonance imaging (ceMRI) protocol providing the above mentioned diagnostic possibilities and to demonstrate its applicability in daily routine. METHODS: Consecutive patients with angina were screened on a 1.5 Tesla system. Functional images in short and long axis orientation were acquired for each patient. First-pass kinetics of a gadolinium-based contrast agent (0.1 mmol/kg) were measured after three minutes of stress with adenosine infusion (140 microg/kg/min). 10 min after a second bolus injection of contrast agent "late enhancement" (MLE) sequences were acquired for the detection of myocardial necrosis. RESULTS: We enrolled 3174 patients referred for ceMRI for detection or exclusion of ischemic heart disease. One patient experienced a major complication due to hyperventilation followed by grand mal seizure. In 1121 (35.3%) patients minor complications, such as mild chest pain or dyspnea (30%), temporarily and asymptomatic AV block (3%) or nausea (2%) could be observed under adenosine infusion. Hypoperfusion in more than one myocardial segment and affecting more than 1/3 of the myocardial wall diameter could be detected in 1972 (62%) patients. Subendocardial hypoperfusion with limited duration could be shown in 897 (28%) patients. In 305 (10%) patients hypoperfusion could be excluded. MLE could be seen in 532 (17%) patients. CONCLUSION: This compiled ceMRI protocol is suitable for detection or exclusion of ischemic heart disease in an outpatient routine. We showed feasibility, applicability and safety of our protocol. CeMRI may serve as a useful surrogate for non-invasive diagnostics prior to invasive coronary angiography in many outpatients.

Adenosine↗

Sirolimus-eluting stent treatment for isolated proximal left anterior descending artery stenoses. Results from the prospective multi-center German Cypher Registry.

BACKGROUND: Stenting of isolated proximal LAD stenoses is still a controversial issue since it is associated with higher target vessel revascularization (TVR) rate than both bypass surgery using the internal mammary artery, and stenting of other coronary artery territories. The sirolimus- eluting stent (SES) has been reported to significantly reduce restenosis rates in de novo coronary lesions. Therefore, we compared patients from the German Cypher Registry treated with SES for isolated proximal LAD lesions with those stented for isolated lesions in the proximal LCX or RCA. METHODS: A total of 349 patients treated with SES were analyzed. 249 patients were treated for proximal LAD stenosis, and 100 for proximal LCX/RCA stenoses. The combined clinical endpoint was MACCE (death of any cause, non-fatal MI and non-fatal stroke) and TVR at 6 months. RESULTS: In-hospital events (death, MI and TVR) did not differ significantly between both groups (3.2% for the LAD group vs 2.0% for the LCX/RCA-group, p=0.73). The combined end point of death of any cause, non-fatal MI and non-fatal stroke at six months was 2.6% in the LAD group, and 2.2% in the LCX/RCA group (p=1.0). TVR occurred in 4.8% of the LAD group and in 6.5% of the LCX/RCA group at six months (p=0.58). The percentage of patients free from angina at daily activities was 80.6% in the LAD group, and 77.4% in the LCX/ RCA group (p=0.52). CONCLUSION: SES once implanted into isolated proximal LAD stenoses appears as effective as reported in other vessel territories. Accordingly, stenting of the proximal LAD using SES might prove a suitable alternative to surgery.

Activities of Daily Living↗

Sniffing human sex-steroid derived compounds modulates mood, memory and autonomic nervous system function in specific behavioral contexts.

We asked whether the effects of exposure to two human sex-steroid derived compounds were context dependent. The effects of sniffing 4,16-androstadien-3-one (AND) and 1,3,5(10),16-estratetraen-3-ol (EST) on mood, memory, and autonomic nervous system responses were explored in 72 participants. Subjects were tested with AND, EST, or a Control compound within four mood contexts: neutral, sexually aroused, sad and happy. These moods were successfully induced using selected film segments (P < 0.0001). During the neutral context, none of the compounds affected mood or autonomic nervous system function. However, compound effects were significantly increased within arousing contexts. During the sexually arousing context, both compounds increased sexual arousal (P < 0.029). During the sad context, AND maintained positive mood in women (P< 0.050) and increased negative mood in men (P < 0.031). Memory for events during the sad context was impaired by AND in women (P < 0.047) but not in men. Finally, effects of AND on physiology were observed during the sexually arousing context whereby AND increased skin temperature in both sexes (P < 0.022) but reduced abdominal respiration rate in men only (P < 0.034). These results suggest that sex-steroidal compounds modulate mood, memory and autonomic nervous system responses and increase their significance within specific behavioral contexts. These findings lend support to a specific role for these compounds in chemical communication between humans.

Adolescent↗

"Real life" use of sirolimus-eluting coronary stents in Germany. Results from the prospective multi-centre German Cypher Registry.

BACKGROUND: Drugeluting stents (DES) are currently judged to be a "break-through" technology for the prevention of restenosis after percutaneous coronary interventions (PCI). However, experience is limited to randomised controlled clinical trials (RCT) in selected lesions and the currently available DES are more expensive compared to conventional "bare" stents. Therefore, actual clinical practice may be very different to RCT. METHODS: We analysed the data of the German Cypher trade mark Registry, a nationwide registry which was initiated in parallel to the launch of the first DES, the Cypher trade mark sirolimus-eluting coronary stent, in April 2002. RESULTS: From April 2002 until March 2003, 1638 procedures at 88 hospitals were included in the German Cypher trade mark Registry. The mean inclusion rate per centre and month remained low (<3 procedures/month and participating hospital) during the whole inclusion period. Most patients presented with stable angina pectoris (45.8%); however, 6.4% of patients were treated for a non-ST elevation myocardial infarction, 10.3% of patients for ST elevation myocardial infarction and 1.7% in cardiogenic shock. In patients without ST elevation myocardial infarction, a de novo stenosis was treated in 68.4% of cases, a restenosis in 4.1%, and an in-stent restenosis in 25.5% of cases. Chronic total occlusions were treated in 6.1% of patients. Predilatation was performed in 68.3% of patients and 1.05 +/- 0.35 Cypher trade mark stents were implanted per patient with a median (quartiles) stent length of 18 (13-21) mm. PCI-related death occurred in 0.1% of patients and a Q-wave myocardial infarction in 1.1%. Urgent re-PCI before hospital discharge was performed in 1.3% and urgent bypass surgery in 0.1% of cases. CONCLUSIONS: The use of the sirolimus-eluting coronary stents in this "real life" registry was found to be safe concerning acute complications. In about one half of the registry patients, the DES was implanted in lesions that were excluded from RCTs.

Blood Vessel Prosthesis↗

[Second and Third Annual Report of the German Society of Coronary Angiography and Interventions in Private Practice (BNK) concerning quality assurance in invasive cardiology].

Since 1995, the German Society for Cardiac Angiography and Interventions in Private Practice (BNK) has been intensely involved in quality assurance; since 1996, it has registered relevant data for diagnostic left heart catheterization (DIAG) and coronary interventions (PTCA). The following data are based on a total of 72,777 cardiac catheters, of which 54,513 were DIAG and 18,264 were PTCA (DIAG in 1996: 10,316; in 1997: 15,692 and in 1998: 28,505. PTCA in 1996: 2,597; in 1997: 5,600 and in 1998: 10,067). The mean patient age was 61.9 years for males and 65.3 years for females (31%). DIAG was performed on an out-patient basis in 60% of the cases. The proportion of self-referrals is circa one-third and has not increased over time. A s/p PTCA was present in 21% of the DIAG patients; those after coronary bypass surgery showed a steadily increasing trend towards a follow-up DIAG (8% of the patients). There was a distinctive decrease in the use of contrast medium from an average of 164 ml (1996) to 138 ml (1998). The symptoms leading to DIAG did not substantially change in the years from 1996 to 1998; the angiographic range of the coronary disease and the degree of an impaired myocardial function have remained virtually unchanged. The treatment recommendations appear to tend towards medical therapy with decreasing indications for PTCA (20%) and open heart surgery (16%). The mean duration of a PTCA procedure decreased from 57 +/- 8 (1996) to 44.6 +/- 25 (1998) minutes. The success rates remained unchanged for coronary stenoses as well as for recanalization of chronic total occlusions. PTCA complications: the incidence of abrupt coronary occlusions was 2% and of emergency bypass surgery 0.4%; mortality was 0.1%.

Aged↗

[First annual report of practitioners of interventional cardiology in private practice in Germany. Results of procedures of left heart catheterization and coronary interventions in the year 1996].

The German Society for Cardiac Angiography and Interventions in Private Practice has started a registry of cardiac procedures since 1996 in order to establish a standard for performance. Although quality management for the cath lab makes sense and is also legally required, there is no generally recommended infrastructure for quality assurance existing in Germany at this time. Therefore, the German Society of Cardiologists in Private Practice (BNK) initiated a project in 1994 to develop a computer program for paperless documentation of diagnostic cardiac catheterizations and coronary interventions (PTCA) using a minimal data set. In 1996, 8 private associated groups participated in this project. The (anonymous) analysis of 10,316 diagnostic cardiac catheterizations and 2597 PTCA yielded the following results: In 95% of the patients, diagnostic cardiac catheterization was performed using the femoral and in 5% the brachial/radial approach. The mean volume of administered contrast medium was 164 +/- 138 ml/patient. The mean LV-EF was greater than 50% in 58.4% of the patients and between 30% and 50% in 10.1%. Coronary artery disease was diagnosed in 69.6% of the patients and valvular/congenital heart disease in 8.5%. In 18.4% of the patients undergoing diagnostic cardiac catheterizations no significant heart disease was identified. Mortality in the cath lab as well as the rate of cerebral insults was 0.05%. In 22.9% and 19% of the patients PTCA and cardiac surgery respectively was recommended. In patients undergoing PTCA, stable angina was present in 74.4% and unstable angina in 13.1%. Of the total number of PTCA procedures, 5.8% were performed in the setting of acute myocardial infarction. The PTCA lesion success rate was 96%, the mean diameter stenosis was 81% pre and 6% post-intervention. The mortality rate at 1 month post-PTCA was 0.4%, and myocardial infarction 1.0%. An acute occlusion occurred in 1.3% of the PTCA patients; 0.6% had to be transferred for emergency bypass surgery. None of the cath labs had on-site surgery. In comparison to other registries, our data show some similarities but also some different trends. Thus, our newly developed software proved to be reliable, fast and easy to use. Participating centers receive immediate feedback regarding their position within the whole group.

Angiocardiography↗

[Stress echocardiography as a routine examination in coronary heart disease].

The value of stress echocardiography in the routine diagnosis of coronary heart disease was assessed in 100 consecutive patients (22 women, 78 men; mean age 57 [32-83] years) scheduled for coronary angiography because of suspected angina. Exercise consisted of bicycle ergometry (n = 50), on the one hand, simulated exercise with transoesophageal atrial stimulation (n = 16), dipyridamole (n = 33) and dobutamine (n = 33) infusions, on the other. 91 patients were successfully tested by at least one of these procedures, while exercise electrocardiography was successfully employed in only 78 (P < 0.05). Stress echocardiography had a greater sensitivity than exercise electrocardiography (90% vs 78%) and specificity (90% vs 73%). Semiquantitative measurement of wall movement distinguished patients without functionally effective stenosis from those with single or multiple vessel disease (P < 0.001). Stress echocardiography thus makes it possible in most cases to demonstrate or exclude functionally significant coronary artery stenoses.

Adult↗

Atrial natriuretic peptide kinetic studies in patients with cardiac dysfunction.

Three studies were performed: (1) a controlled investigation of alpha-human atrial natriuretic peptide (alpha-hANP) total body production and metabolic clearance rates using a bolus infusion technique (controls, patients 1 to 6); (2) a study of alpha-hANP kinetics in cardiac dysfunction patients using a constant infusion method (patients 7 to 14); and (3) a right heart catheterization study to determine the amount of alpha-hANP released into the circulation at the level of the right heart, estimated by the step-up in alpha-hANP concentration between the superior and inferior vena cava and the pulmonary artery, in the patients with left ventricular dysfunction. Baseline venous plasma alpha-hANP was 27.3 +/- 16.5 pg/ml in the controls (mean +/- SD; N = 6), 141.6 +/- 138.0 pg/ml in patients 1 to 6 (P less than 0.05 compared to controls), and 167.5 +/- 145.7 pg/ml in patients 7 to 14. Total body alpha-hANP production rate was markedly elevated in patients 1 to 6 compared to controls (0.45 +/- 0.36 vs. 0.11 +/- 0.06 micrograms/min, P less than 0.05) and was similar to that determined by the continuous infusion technique in patients 7 to 14 (0.62 +/- 0.44 micrograms/min, P = 0.49 compared to patients 1 to 6). alpha-hANP release into the right heart (0.17 +/- 0.11 micrograms/min), however, was significantly lower than total body production rate in the cardiac dysfunction patients, indicating that total body alpha-hANP secretion occurs from sites in addition to drainage into the right heart via the coronary sinus and anterior cardiac veins. Right atrial pressure correlated with the alpha-hANP released into the right heart.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Unexpected malposition of a ventricular pacemaker electrode].

Ten years after mitral-valve replacement, a 69-year-old patient underwent VVI pacemaker implantation because of symptomatic bradyarrhythmia. Postoperatively, the electrocardiogram showed a right bundle branch pattern under ventricular stimulation while the threshold was optimal. Under fluoroscopy, we suspected a malposition of the electrode outside the right ventricle in the LAO and lateral view. This could not be verified by echocardiography, whereas contrast angiography of the right ventricle proved the extracavitary position of the electrode under the inferior wall of the left ventricle, probably in the middle cardiac vein. The electrode position was operatively corrected without complications. We discuss different ways of malposition and their detection by considering electrocardiographic configuration and fluoroscopy in LAO and lateral view.

Aged↗

[Is pre-hospital thrombolysis in acute myocardial infarct valuable as a routine measure?].

UNLABELLED: In 4920 consecutive missions of the mobile intensive care unit Klinikum Steglitz, 1226 patients (25%) had chest pain of presumed cardiac origin. In 272 patients (22%) an acute myocardial infarction (AMI) was diagnosed in the field. In four patients the diagnosis was wrong; 11 patients with proven coronary artery disease had significant ST-segment elevation, but did not develop AMI. In hospital, a total of 406 patients had evidence of AMI; 173 of these (41%) were seen by an emergency physician in the field already within the first hour after onset of symptoms. In 6%, diagnostic ST-elevation was not recognized by the emergency physician; 27% had non-diagnostic ECG changes (11% bundle-branch block). Prehospital thrombolysis within 4 h after symptom onset was performed in 126 of 205 patients (61%); 74 of these patients were seen by the emergency physician within the first hour. The main reason for exclusion was advanced age. Inclusion of older patients and also those with bundle-branch block could further increase the prehospital thrombolysis rate. CONCLUSION: With an effective emergency medical system a large proportion of all patients with AMI can correctly be identified and properly treated with a thrombolytic drug in the field. The time gain is considerable.

Aged↗

Comparison of the effect of isosorbide-5-mononitrate and isosorbide dinitrate in a slow-release form on exercise-induced myocardial ischemia.

A randomized, double blind, placebo-controlled crossover study on 20 patients with exercise-induced angina pectoris and reproducible ST-segment depression during exercise-stress test was performed to compare the effect of a single dose of 120 mg of isosorbide dinitrate in a slow-release form with that of a twice-daily application of 20 mg of isosorbide-5-mononitrate. Symptom-limited exercise tests were done, and nitrate plasma levels were measured in the subjects 6, 10, and 24 hours after the first administration of the drug. Both drugs produced a highly significant reduction in the size of exercise-induced ST-depressions (P less than .001) 6 and 10 hours after the first administration of isosorbide dinitrate as well as 6 hours after the first and 4 hours after the second dose of isosorbide-5-mononitrate. The effect was still significant (P less than .05) 24 hours after the administration of isosorbide dinitrate in a slow-release form and 18 hours after the second dose of isosorbide-5-mononitrate. In the case of the drug isosorbide dinitrate, nitrate plasma levels for its metabolite, isosorbide-5-mononitrate, were highest 10 hours after first application. In the case of the drug isosorbide-5-mononitrate, nitrate plasma levels were highest 4 hours after the second dose. Two 20 mg doses of isosorbide-5-mononitrate and a single dose of 120 mg isosorbide dinitrate in a slow release form have a comparable effect on the reduction of exercise-induced ST-segment depressions.

Adult↗