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Alexander Tenenbaum

Publications and source records attributed to Alexander Tenenbaum.

52 records · Page 3Linked to original sources
PubMed2003

Functional capacity impairment in patients with coronary artery disease: prevalence, risk factors and prognosis.

BACKGROUND: Some patients developing heart failure and functional capacity impairment have no history of myocardial infarction (MI), and stable angina pectoris is their principal clinical manifestation of coronary artery disease (CAD). The present study was aimed to evaluate the outcome of CAD-related functional capacity impairment in patients with and without a history of MI over a 7.7-year follow-up. METHODS: The study sample comprised 14,283 coronary patients aged 45-74 years, screened for participation in the Bezafibrate Infarction Prevention study. The presence of NYHA functional class II was defined as mild functional capacity impairment and the presence of NYHA functional class III-IV was defined as advanced functional capacity impairment. RESULTS: The patients were divided in two groups: (1) those with a history of MI, 10,307 patients, who formed three subgroups: NYHA I 7,551 patients (73.3%); NYHA II 2,176 patients (21.1%); NYHA III + IV 580 patients (5.6%), and (2) those without a history of MI, 3,976 patients, who also formed three subgroups: NYHA I 2,744 patients (69.0%); NYHA 981 patients (24.7%); NYHA III + IV 251 patients (6.3%). Multivariate analysis identified a history of MI as a consistent predictor of increased all-cause and cardiac mortality for patients with NYHA I, II and III + IV subgroups with escalating significance for patients with advanced functional capacity impairment: hazard ratios of 1.55 (95% CI 1.36-1.75), 1.56 (95% CI 1.30-1.86) and 1.72 (95% CI 1.24-2.40) for all-cause and 1.93 (95% CI 1.60-2.33), 1.73 (95% 1.35-2.20) and 3.22 (95% CI 1.87-5.54) for cardiac mortality, respectively. CONCLUSIONS: The prevalence of low functional capacity is similar among coronary patients with and without a history of MI, but their long-term survival differs substantially in favor of the latter. Therefore, two different types of CAD-related advanced functional capacity impairments (post-MI and non-post-MI) can be distinguished.

Aged↗
PubMed2002

Coherent dynamics in a butane molecule.

We have simulated by molecular dynamics a single molecule of butane in a thermal bath at different temperatures. We have found that the collective degrees of freedom of the essential dynamics are endowed with quite different degrees of coherence, and that those subject to the largest fluctuations are also the most coherent, that is, the least chaotic. We suggest that this pattern may be characteristic also of larger molecules. A detailed assessment of the degree of coherence has been obtained by computing in the tangent space the whole set of generalized coherence angles.

Journal Article↗
PubMed2002

Losartan and diabetic nephropathy: commentaries on the RENAAL study.

The RENAAL (Reduction of Endpoints in NIDDM with the Angiotensin II Antagonist Losartan) study is a multinational, double-blind, randomized, placebo controlled trial which was recently published. It was aimed to evaluate the effect of the angiotensin receptor blocker losartan in patients with diabetic nephropathy. The primary efficacy measure was the time to the first event of the composite end point of a doubling of serum creatinine, end-stage renal disease, or death. The conclusion was that losartan led to significant improvement in renal outcomes, that was beyond that attributable to blood pressure control in patients with type 2 diabetes and nephropathy. The perusal of the report raises concern, regarding to both the patient population as well as the outcome measures. At randomization, the placebo group included more patients with angina, myocardial infarction and lipid disorders than the losartan group. Information on glucose metabolism was disregarded, and data on antihyperglycemic therapy--which may have undesirable influences on cardiac performance--were not included in a multivariate analysis. In addition, only data on first hospitalization were reported, whilst information on total specific-cause hospitalizations was disregarded, thus potentially masking further unfavorable events. Furthermore, creatinine seems not to be a reliable surrogate end point. Based on its mechanism of action, losartan may possess favorable renoprotective properties. However, due to the methodological flaws and the incomplete data in the RENAAL study, the question of the effectiveness and safety of this drug in diabetic nephropathy remains yet unanswered.

Journal Article↗
PubMed2002

Transcutaneous detection of aortic arch atheromas by suprasternal harmonic imaging.

OBJECTIVES: The goal of the present study was to examine whether suprasternal harmonic imaging (SHI) (i.e., harmonic imaging from the suprasternal windows) can visualize protruding arch atheromas (PAAs) and reliably predict the presence or absence of significant lesions. BACKGROUND: Protruding arch atheromas are a major source of cerebral and peripheral embolism and probably the most frequent cause of stroke during cardiac catheterization and open-heart surgery. Preprocedural screening by transesophageal echocardiography (TEE) would be desirable but is limited by the nature of the examination. METHODS: Of 354 patients who underwent a TEE study in our laboratory during the study period, 106 were referred for detection of a source of embolism. Findings were classified based on the French Aortic Plaque study criteria as: 1) no or minimal atherosclerotic changes; 2) PAAs < 4 mm; 3) PAAs > or =4 mm or presence of a mobile component. RESULTS: Adequate transcutaneous image quality could be achieved in 89 patients (84%). Protruding arch atheromas were present in 42 patients (47%) and absent in 47 (53%). Positive and negative predictive values for large PAAs on TEE were 91% and 98%, respectively. In one case, SHI detected a complex PAA inaccessible for TEE due to interposition of the left bronchus as demonstrated by dual helical computed tomography. Inter-observer agreement for SHI was 91%. CONCLUSIONS: Suprasternal harmonic imaging reliably predicted or excluded the presence of PAAs in a sizable, consecutive group of patients referred to TEE for detection of a source of embolism. It represents an excellent screening test and provides complimentary views of regions, which may be blind spots for TEE.

Aorta, Thoracic↗
PubMed2002

Systemic hypertension in postmenopausal women: a clinical approach.

Gender-specific differences in the incidence of cardiovascular disease have long been known, and estrogens have been considered to be responsible for this dissimilarity. Recently, the steep increase in cardiovascular risk in the no longer fertile woman has become evident. The postmenopausal metabolic syndrome is very frequent, with obesity, insulin resistance, and hyperinsulinemia, which convey increased sodium reabsorption, stimulation of the sympathetic nervous system, and smooth muscle growth. The clinical corollary of these overall changes is hypertension. Gender differences in components of the renin-angiotensin system have been shown to exist, and may play a central role in blood pressure control. In normotensive populations, plasma renin activity is significantly higher in men than in women, and is higher in postmenopausal versus premenopausal women. Two angiotensin-converting enzyme inhibitors, ramipril and moexipril, have undergone trials aimed specifically at older people with cardiovascular risk and with postmenopausal hypertension, and could be the first therapeutic choice. However, a comprehensive treatment should include nonpharmacologic measures with strong emphasis on weight normalization and regular physical activity, prevention of osteoporosis, as well as decisions on the use of estrogen replacement therapy and treatment of the menopausal metabolic syndrome. Finally, education of both patients and physicians on the nature and prognosis of untreated hypertension is crucial.

Adult↗
PubMed2002

Does participation in a long-term clinical trial lead to survival gain for patients with coronary artery disease?

PURPOSE: Little is known about the advantages and disadvantages of participation in a clinical trial for patients with coronary heart disease. We hypothesized that participation itself in a long-term clinical trial with regular clinical evaluation and adjustment of treatments might lead to survival gain among patients with coronary artery disease who agreed or refused to participate in the Bezafibrate Infarction Prevention study. SUBJECTS AND METHODS: The study was performed in 18 university hospitals. There were 3502 patients who fulfilled the inclusion criteria. Among them, 3122 patients signed informed consent and were included in the study ("participants"), whereas 380 declined to participate ("nonparticipants"). For all participants, routine visits to the clinics were scheduled bimonthly for study medication distribution and compliance assessment, and every 4 months for clinical evaluation and management. Nonparticipants continued with community-based treatment and were followed only for mortality. RESULTS: The two groups were similar with regard to age, sex, and the prevalence of most cardiovascular diseases, risk factors, and medications, except that participants were more likely to have presented with an anginal syndrome (1788 [57%] vs. 190 [50%]) and to have symptomatic heart failure (754 [25%] vs. 66 [18%]). During follow-up (mean [+/- SD], 7.7 +/- 0.8 years), 475 patients died. All-cause mortality was similar in participants (n = 423 [13.6%]) and nonparticipants (n = 52 [13.7%]). In a multivariate analysis, participation in the clinical trial was not associated with all-cause mortality (hazard ratio [HR] = 0.96; 95% confidence interval [CI]: 0.70 to 1.30) or cardiac mortality (HR = 1.12; 95% CI: 0.72 to 1.74). CONCLUSION: Participation in a long-term clinical trial in a country with readily accessible community-based medicine may not lead to survival gain in patients with coronary artery disease.

Aged↗
PubMed2002

Combined coronary and mitral annulus calcium detection in the non-invasive diagnosis of coronary artery disease in patients with systemic hypertension.

BACKGROUND: Although the presence of coronary calcium (CC) on fast spiral computed tomography (FSCT) is a powerful predictor of coronary artery disease (CAD), both the specificity and positive predictive value (PPV) of CC in CAD diagnosis are modest. Since previous studies have shown an association between mitral annular calcification (MAC) and coronary atherosclerosis, we aimed to investigate whether combined coronary and MAC detection could improve the non-invasive diagnosis of CAD. DESIGN AND METHODS: Our study comprised 522 patients (284 men and 238 women, age ranged from 52-80 years, mean 65 +/- 6 years) who underwent FSCT of the coronaries as well as echo-Doppler examination. Among them, 97 patients had prior diagnosis of prevalent proven CAD (CAD group) while 425 patients were without clinically manifested CAD (the No CAD group). RESULTS: The prevalence of CC in the CAD group was 95 versus 68% in the No CAD group (P = 0.001). The prevalence of MAC in CAD group was 63 versus 51% in No CAD group (P = 0.03). Sensitivity and negative predictive value (NPV) of CC as a predictor of CAD were 95 and 96% respectively, but specificity and PPV were low: 32 and 24% respectively. Sensitivity and NPV of MAC as predictors of CAD were 63 and 85% respectively; specificity and PPV, 49 and 22% respectively. Using of combined CC and MAC evaluation in the prediction led to some specificity improvement at the expense of a similar sensitivity reduction, without a considerable gain in the total accuracy of the method. CONCLUSIONS: Coronary calcium detection on FSCT in hypertensive patients yields excellent sensitivity and NPV but relatively low specificity and PPV for clinically manifested CAD. Mitral annular calcification assessment yields a low sensitivity and specificity and its addition to CC evaluation does not improve non-invasive diagnosis of CAD.

Aged↗
PubMed2002

Aortic valve calcium on spiral computed tomography (dual slice mode) is associated with advanced coronary calcium in hypertensive patients.

BACKGROUND: Aortic valve calcium (AVC) is common in the elderly and is associated with an increase risk of death from cardiovascular causes and of myocardial infarction. The goal of the present study was to determine whether an association exists between the presence of AVC and coronary calcium (CC) in high-risk hypertensive patients as detected by spiral computed tomography (dual slice mode) (DHCT). DESIGN AND METHODS: Three hundred and seventy-six hypertensive patients participating in the International Nifedipine Gastrointestinal Therapeutic System (GITS) Study of Intervention as a Goal in Hypertension Treatment (INSIGHT) in our region were included (197 men and 179 women, age range 55-79 years). All underwent DHCT of the heart for CC scoring using previously published methods. A positive test for the presence of CC was defined as the presence of at least one lesion with an area of 0.5 mm and DHCT density above 90 Hounsfield units (total CC score >0). CC was considered advanced when total calcium score was >300. AVC was defined by DHCT as any detected calcified deposit in the region of the aortic valve. Patients without AVC served as the control group. RESULTS: AVC was documented in 70 patients (36 men, 34 women; mean age 66 +/- 5 years, range 57-79 years). The age- and sex-matched non-AVC group (control group) included 306 patients (161 men, 145 women; mean age 67 +/- 5 years, range 55-75 years). There were no intergroup differences in risk factors for atherosclerosis. Significant differences were found between AVC and the control groups for mean CC score (388 +/- 754 compared with 147 +/- 307, P< 0.001) and between the presence of advanced CC and the control group (27 compared with 15%, P= 0.02). Significant differences were also found for the presence of three-vessel calcification (36 compared with 21%, P= 0.01) and the number of vessels involved (1.8 +/- 1.1 compared with 1.4 +/- 1.1, P= 0.01). Stepwise logistic regression found age [odds ratio (OR) 1.08, 95% confidence intervals (CI) 1.03-1.15), gender (OR 0.45, 95% CI 0.25-0.82) and AVC (OR 2.07, 95% CI 1.06-4.02)] to be the only variables that predict advanced CC. CONCLUSIONS: Our study demonstrated a significant association between the presence of AVC and advanced CC on spiral computed tomography. These results strengthen earlier findings of a high association between AVC and increased risk of death from cardiovascular causes.

Age Factors↗
PubMed2002

Autoantibodies to cardiolipin and beta-2-glycoprotein-I in coronary artery disease patients with and without hypertension.

BACKGROUND: Autoantibodies to cardiolipin (aCL) and beta2-glycoprotein-I (beta2GPI) are considered proatherogenic. Elevated levels of both antibodies have been reported in hypertension. Nonetheless, there are no data regarding an association between these autoantibodies and hypertension in coronary artery disease. METHODS: The levels of aCL and anti-beta2GPI antibodies were measured in patients having coronary artery disease with (n = 82) or without (n = 36) hypertension, in association with other major risk factors for coronary artery disease. RESULTS: The levels of aCL and anti-beta2GPI antibodies were (OD at 405 nm) 0.23 +/- 0.14 and 0.22 +/- 0.12 in the normal blood pressure group, as opposed to 0.24 +/- 0.12 and 0.20 +/- 0.12 in the hypertensive group, respectively (p = 0.67; 0.42). No significant difference in either antibody levels was found between hypertensive patients with normal and abnormal blood pressure measurements. The presence of additional risk factors did not affect antibody levels in normotensive patients. However, in the hypertensive group, the presence of smoking was associated with significantly decreased anti-beta2GPI antibody levels, whereas no change was found in aCL. Further, patients who had hypertension, smoking and hypercholesterolemia, had significantly decreased anti-beta2GPI antibody levels compared with patients without any of these risk factors (0.13 +/- 0.04 versus 0.23 +/- 0.13, respectively; p = 0.02). CONCLUSION: Hypertension is not associated with modification of aCL and anti-beta2GPI antibody levels in coronary artery disease patients. However, there are elevated anti-beta2GPI antibody levels in patients without conventional risk factors compared with patients with these risk factors.

Anticoagulants↗
PubMed1997

Leiomyosarcoma of the Right Atrium Masked by a Covering Thrombus: Conflicting Results of Echocardiography and Transvenous Biopsy-In Favor of Echocardiography.

A 62-year-old woman was admitted for the evaluation of pedal edema and ascitis. Echocardiography revealed a right atrial (RA) mass invading the interatrial septum and extending into the inferior vena cava (IVC). Contrast enhanced computerized tomography scan excluded extravascular involvement. An organized thrombus was diagnosed by transvenous endomyocardial biopsy. The patient was treated with continuous intravenous heparin, and died soon after from hepatic failure. Postmortem histologic examination revealed a leiomyosarcoma surrounded by a thrombus involving RA, IVC, and hepatic veins. Endomyocardial biopsy played a misleading role that affected patient's management.

Journal Article↗
PubMedDate not supplied

Admission blood glucose level and mortality among hospitalized nondiabetic patients with heart failure.

BACKGROUND: The significance of admission blood glucose level in nondiabetic patients with heart failure (HF) is unknown. We examined the possible association between admission glucose levels and outcome in a large cohort of hospitalized patients with HF. METHODS: We analyzed the data of 4102 patients with HF, who were hospitalized during a prospective national survey. The present study focuses on a subgroup of 1122 nondiabetic patients with acute HF who were admitted because of acute HF or exacerbation of chronic HF. RESULTS: In-hospital mortality was twice as high in patients with admission blood glucose levels in the third tertile (7.2%) compared with the first (3%) and second (4%) tertiles (P = .02). Furthermore, mortality risk was correlated with admission glucose levels; each 18-mg/dL (1-mmol/L) increase in glucose level was associated with a 31% increased risk of in-hospital mortality (adjusted odds ratio, 1.31; 95% confidence interval, 1.10-1.57; P = .003) and a 12% increase in 60-day mortality (adjusted hazard ratio, 1.12; 95% confidence interval, 1.01-1.25; P = .04). Admission blood glucose levels remained an independent predictor of in-hospital and 60-day mortality even after the exclusion of 315 patients (28%) with acute myocardial infarction and HF. The 6- and 12-month mortality rates were similar in patients with and without abnormal admission blood glucose levels. CONCLUSIONS: Elevated admission blood glucose levels are associated with increased in-hospital and 60-day mortality, but not 6-month or 1-year mortality, in nondiabetic patients hospitalized because of HF.

Aged↗