PubMed Health⌕ Search

Biomedical subjects

Dov Freimark

Publications and source records attributed to Dov Freimark.

At least 19 recordsLinked to original sources
PubMed2006

Long-term versus intermediate-term supervised exercise training in advanced heart failure: effects on exercise tolerance and mortality.

AIM: To date there have been no studies exploring the effects of long-term versus intermediate-term and short-term supervised exercise training program in patients with severe chronic heart failure (CHF) on optimal medical therapy. We assessed exercise tolerance and mortality in CHF patients undergoing long- versus intermediate-term exercise training (ET). METHODS: Forty-two consecutive severe CHF patients (New York Heart Association functional class III) were referred for a supervised exercise and cardiac rehabilitation program and were followed-up for 3 years: 20/42 (48%) patients discontinued ET after intermediate-term period of 1.6+/-0.8 years (Group A, intermediate-term ET), and 22/42 (52%) remained on the ET program for 3.0+/-0.3 years (Group B, long-term ET). Exercise duration, 6-min walked distance and metabolic equivalents (METs) assessed by modified Bruce protocol were recorded before, 4.5 months after, and 3 years after initiation of ET. RESULTS: Both groups were comparable regarding age, gender, prevalence of ischemic etiology, mean ejection fraction and medications. Risk factors for ischemic heart disease were similar, except for the prevalence of diabetes, which was higher in Group A compared to Group B (11/20 versus 5/22, p=0.03). Significantly more Group A patients died after ET discontinuation (4/20 versus 0/22, p=0.01). At the end of follow-up a significant improvement could be seen in Group B patients compared to A in exercise duration, 6-min walked distance and metabolic equivalents (p<0.01 for all). CONCLUSIONS: Higher survival rate was observed in severe CHF patients undergoing long-term versus intermediate-term exercise training. Long-term supervised exercise training is safe and improves exercise tolerance in these patients.

Exercise Therapy↗
PubMed2006

Short-term sibutramine therapy is associated with weight loss and improved endothelial function in obese patients with coronary artery disease.

In obese patients with coronary artery disease (CAD), the vascular endothelium is usually impaired, and the modification or reversal of endothelial dysfunction may significantly enhance treatment. Sibutramine, a serotonin and norepinephrine transporter blocker, is widely used as an adjunctive obesity treatment, but its impact on endothelial function in obese patients with CAD has not yet been investigated. Eighty consecutive obese, nonhypertensive, stable patients with CAD (65 men; mean age 65 +/- 11 years, mean body mass index 32 +/- 3 kg/m2) were randomly assigned to either sibutramine 10 mg/day (n = 40) or routine treatment (n = 40; controls) for 4 months. The percentage improvement in endothelium-dependent brachial artery flow-mediated dilation (%FMD) and endothelium-independent nitroglycerin-mediated vasodilation were assessed at baseline and after 4 months using high-resolution ultrasound. At baseline, all patients had %FMD of 5.4 +/- 3.1% and percentage improvement in endothelium-independent nitroglycerin-mediated vasodilation of 9.2 +/- 2.9%, showing no significant differences. After 4 months, however, initial body weight was reduced by 11.4 +/- 1.2% in the sibutramine group compared with only 2.2 +/- 1.3% in controls (p <0.001), demonstrating a significant improvement in postintervention %FMD (8.9 +/- 2.4%, p = 0.01, compared with baseline) in the sibutramine group compared with controls (5.2 +/- 3.6%, p = 0.68, compared with baseline). No significant therapeutic effect on the percentage improvement in endothelium-independent nitroglycerin-mediated vasodilation was seen in either group (9.2 +/- 2.5% vs 9.1 +/- 3.0%, respectively, p = 0.792). In addition, sibutramine therapy was associated with significant C-reactive protein reduction compared with routine treatment (44% vs 9%, p = 0.035). Thus, short-term therapy with sibutramine, together with diet and lifestyle intervention, is associated with improved endothelial function assessed by brachial artery %FMD in nonhypertensive, stable patients with CAD.

Aged↗
PubMed2006

Improvement of congestive heart failure by upgrading of conventional to resynchronization pacemakers.

AIMS: To compare the clinical response of patients with right ventricular apical pacing (RVAP) upgraded to cardiac resynchronization therapy (CRT) to that of previously nonpaced heart failure (HF) patients who had de novo CRT implantation. BACKGROUND: The role of CRT in patients with wide QRS and HF due to RVAP is less well established than in other CRT candidates. METHODS: Ninety-eight consecutive patients with CRT were studied (mean age 70, mean ejection fraction 0.23). Group A: patients having RVAP prior to CRT implantation (n = 25), group B: patients without prior RVAP (n = 73). Clinical and echocardiographic parameters were recorded prior to, and 3 months after, CRT implantation. RESULTS: Group A patients had a wider QRS at baseline compared to group B (203 +/- 32 ms vs 163 +/- 30 ms respectively, P < 0.001), and a shorter 6-minute walking distance (222 +/- 118 m vs 362 +/- 119 m, respectively, P < 0.005). Otherwise, clinical and echocardiographic parameters were not different. At follow up, group A patients had an average 0.7 +/- 0.5 decrease in their NYHA functional class, compared to 0.3 +/- 0.7 in group B patients (P < 0.05). Six-minute walking distance increased by 93 +/- 113 m in group A, versus 36 +/- 120 m in group B (P = 0.22). There was no difference in echocardiographic response to CRT between the groups. CONCLUSIONS: HF patients with prior RVAP demonstrate clinical improvement after upgrading to CRT that is comparable, and in some aspects, even better than that observed in HF patients with native conduction delay who undergo de novo CRT implantation.

Aged↗
PubMed2005

Cognitive functions in severe congestive heart failure before and after an exercise training program.

BACKGROUND: Congestive heart failure is associated with cognitive impairment, particularly of attentional skills. We assessed, in a hypothesis-generating study, the effect of an exercise training program on cognitive functions among patients with severe congestive heart failure. METHODS: Patients with severe congestive heart failure (n=20; New York Heart Association functional class III; left ventricular ejection fraction < or =35%) were evaluated before and following a standardized and supervised exercise training program (x2/week for 18 weeks; exercise group), while 5 additional patients did not undergo an exercise training program (control group). A battery of cognitive tests was used to assess cognitive functions. Physical performance was assessed by the 6-min walk test and the modified Bruce exercise test, cardiac index and systemic vascular resistance using thoracic electrical bioimpedance, and cerebral vasomotor reactivity to hypercapnia by means of the breath-holding index using transcranial Doppler. RESULTS: Time of completion of the trail making A (105+/-116 to 75+/-52; p=0.02) and B (169+/-100 to 119+/-65; p=0.002) tests, and of the Stroop part A (40+/-13 to 37+/-13; p=0.04) was shorter in patients completing the exercise training program, but not in control patients, while the other neuropsychological measures remained unchanged in both groups. Cerebral vasomotor reactivity to hypercapnia remained diminished (breath-holding index 0.64+/-0.27 vs. 0.68+/-0.37) despite significant improvements in exercise capacity (6-min walk test 308+/-87 to 423+/-91 m, p<0.001; modified Bruce exercise test 5.6+/-3.8 to 9.8+/-3.4 min, p<0.001). CONCLUSIONS: Patients with severe congestive heart failure undergoing an exercise training program improve in some measures of cognitive functions that are limited to general attention and psychomotor speed. Based on these preliminary findings, further evaluations are designed within the framework of a larger controlled clinical trial.

Adult↗
PubMed2005

Impact of left ventricular filling properties on the benefit of exercise training in patients with advanced chronic heart failure secondary to ischemic or nonischemic cardiomyopathy.

This study examined left ventricular (LV) filling properties and exercise hemodynamics noninvasively before and after an exercise training program in patients with chronic heart failure (HF). Although exercise training did not improve LV filling properties in patients with advanced HF, LV filling properties determined the hemodynamic benefit attainable from exercise in this patient group.

Chronic Disease↗
PubMed2005

Genetic ideology of dilated cardiompathy.

Familial cardiomyopathies represent a substantial portion of idiopathic dilated cardiomyopathy in clinical practice. Diversity of clinical presentations and variability in penetrance lead to under-recognition of this disease entity as an inherited disorder. The mechanisms by which mutations in different genes perturb cardiac function and lead to pathologic remodeling help us understand the molecular pathways in disease pathogenesis and define the potential targets for therapeutic interventions. Appreciating when DCM is inherited might spare unnecessary diagnostic efforts and, instead, help give appropriate attention to the timely detection of subclinically affected family members. Establishing preventive therapy in asymptomatic family members showing early signs of cardiac dysfunction might prevent death and slow down progression to end-stage heart failure.

Age of Onset↗
PubMed2005

The intensive statin therapy myth.

Statins play an important role in the treatment and prevention of coronary artery disease and atherosclerosis. Currently, however, despite its important qualities, the use of statin therapy in the treatment of CAD patients ranges only between 30 and 60% in Europe, the United States and Israel. A wide gap still exists between the numerous scientific publications demonstrating the beneficial effects of statins and the low rate of implementing the guidelines in practice. A Medline search up to June 2005 on all prospective, double-blind, randomized clinical trials evaluating the impact of intensive statin therapy (any statin dose >40 mg/daily) on clinical outcomes after a 1 year follow-up revealed only eight trials. In all the eight trials, with a follow-up period of 12-60 months, intensive statin therapy was significantly more effective than and at least as safe as placebo or other standard statin regimens. Thus, based on the current evidence-based medicine, intensive statin therapy enables more patients with CAD to achieve the current National Cholesterol Education Program goal for low density lipoprotein, while ensuring a relatively high safety profile.

Cholesterol, LDL↗
PubMed2004

Impact of short-term intermittent intravenous dobutamine therapy on endothelial function in patients with severe chronic heart failure.

BACKGROUND: Intermittent intravenous dobutamine therapy is used to treat patients with decompensated end-stage chronic heart failure (CHF), in whom the vascular endothelium is usually impaired. Although it has been suggested that modification or reversal of endothelial dysfunction may be of significant therapeutic benefit, the impact of short-term intermittent intravenous dobutamine therapy on flow-mediated dilation (FMD) in patients with severe decompensated end-stage chronic CHF has not been assessed. METHODS: We prospectively assessed the impact of intermittent intravenous low-dose dobutamine therapy on endothelium-dependent brachial artery FMD and endothelium-independent nitroglycerin (NTG)-mediated vasodilation using high resolution ultrasound scanning in 20 consecutive male patients with severe CHF and ischemic cardiomyopathy (New York Heart Association functional class IV), at baseline and after 4 months, and compared them to 20 age- and sex-matched control subjects. The cardiac index (CI), stroke index (SI), and systemic vascular resistance (SVR) were assessed non-invasively with a thoracic electrical bioimpedance device before and after intravenous dobutamine therapy. RESULTS: Intermittent intravenous dobutamine therapy resulted in significant improvement in post-intervention FMD compared with baseline (7.7% +/- 2.4% vs 1.1% +/- 2.6%; P = .001), a finding not evident in control subjects (1.3% +/- 2.6% vs 1.2% +/- 2.1%; P = .78). There was no significant effect of dobutamine treatment compared with control subjects on NTG-induced vasodilation (7.6% +/- 5.5% vs 7.5% +/- 8.8%, P = .979). Short-term dobutamine therapy also significantly improved SVR (1797 +/- 926 dyne sec/cm5 vs 2172 +/- 1133 dyne sec/cm5, P = .05), CI (2. 4+/- 0.6 L/min/m2 vs 1.9 +/- 0.6 L/min/m2, P = .01), and SI (33.5 +/- 11.7 mL/m(2) vs 27.2 +/- 12.4 mL/m2, P = .02). CONCLUSIONS: Short-term intermittent intravenous low-dose dobutamine therapy significantly improved vascular endothelial function, perhaps demonstrating an additional mechanism for improved SVR, CI, and SI in patients with severe CHF.

Adrenergic beta-Agonists↗
PubMed2004

Ischemic preconditioning: nearly two decades of research. A comprehensive review.

The phenomenon of "ischemic preconditioning" has been recognized for almost two decades. In experimental animals and humans, a brief period of ischemia has been shown to protect the heart from more prolonged episodes of ischemia, and reduce the degree of impaired ventricular function or subsequent damage. Ischemic preconditioning is classified into two distinct components: the classic early preconditioning and the delayed or late preconditioning, each with its own biologic mechanism of adaptation. A comprehensive understanding of these mechanisms and application to clinical scenarios has the promise of providing unique opportunities, particularly regarding the development of preconditioning mimetic agents. Administration of these mimetic drugs or procedures could potentially advance the use of preconditioning as a therapeutic tool and/or preventive factor for cardiovascular disease.

Animals↗
PubMed2004

Hemodynamics during humoral rejection events with total versus standard orthotopic heart transplantation.

PURPOSE: We hypothesized that total orthotopic heart transplantation (TOHT) improves humoral rejection hemodynamics compared with biatrial transplantation or standard orthotopic heart transplantation (SOHT). METHODS: We reviewed 1942 biopsies from 134 patients (pts) and right heart catheterization data obtained at endomyocardial biopsy. Biopsies that displayed humoral rejection by histological findings and positive immunofluorescence for immunoglobulins and complement were analyzed. Patients with pacemakers, atrial fibrillation or beta-blocker therapy at the time of biopsy were excluded. Thirty-two pts after TOHT and 22 after SOHT matching these criteria were identified. RESULTS: Demographic data, underlying disease, pretransplant hemodynamics, and donor demographics were similar. Cardiac output and index were higher in the total orthotopic group (5.9+/-1.1 vs 5.1+/-1.4 L/min, p=0.027; 3.3+/-0.5 vs 2.8+/-0.6 L/min/m2, p=0.016). Right atrial and pulmonary capillary wedge pressure were lower after TOHT (7+/-3 vs 11+/-5 mmHg, p<0.001; 13+/-4 vs 16+/-5 mmHg, p=0.035). Pulmonary pressures, pulmonary vascular resistance and heart rate were similar. CONCLUSION: TOHT offers improved hemodynamics during humoral rejection as evidenced by higher cardiac output and index with lower right atrial and pulmonary capillary wedge pressures. Future studies must examine the potential benefits of TOHT during combined cellular and humoral rejection events.

Anastomosis, Surgical↗
PubMed2003

Association of elevated homocysteine levels with a higher risk of recurrent coronary events and mortality in patients with acute myocardial infarction.

BACKGROUND: Despite the prothrombotic and proinflammatory effects associated with elevated homocysteine levels, only limited data exist regarding the effect of homocysteine levels on outcome of patients with acute myocardial infarction. METHODS: Homocysteine levels were determined within 24 hours of presentation in 157 consecutive patients with acute myocardial infarction. Patients were allocated to 2 groups: those with homocysteine levels of 2.7 mg/L (20 micro mol/L) or more (n = 22 [14%]) and those with homocysteine levels of less than 2.7 mg/L (n = 135 [86%]). RESULTS: Female and diabetic patients had significantly lower homocysteine levels than males (P<.01) and nondiabetic patients (P =.005), respectively, with no significant correlation with age (r = 0.07, P =.42) or other risk factors. Patients with homocysteine levels greater than or equal to 2.7 mg/L and less than 2.7 mg/L did not differ significantly regarding extent of coronary artery disease as reflected by prevalence of multivessel disease (54% vs 61%; P =.87), and their in-hospital course. However, in a mean +/-SD follow-up of 30 +/- 10 months, patients with homocysteine levels greater than or equal to 2.7 mg/L had a higher incidence of recurrent coronary events (36% vs 17%; P =.04) and death (18% vs 5%; P<.05). Homocysteine levels greater than or equal to 2.7 mg/L remain a significant determinant of recurrent coronary event and/or death after controlling for potential cofounders by multivariate analysis (odds ratio, 3.8; 95% confidence interval, 1.3-11.0). CONCLUSIONS: In patients with acute myocardial infarction, elevated homocysteine levels are associated with a higher risk of recurrent coronary events and death, independent of other risk factors and the extent of coronary artery disease.

Aged↗
PubMed2003

Primary angioplasty with routine stenting compared with thrombolytic therapy in elderly patients with acute myocardial infarction.

BACKGROUND: Prior studies have yielded conflicting data on the advantage of primary angioplasty compared with thrombolysis in elderly patients with acute myocardial infarction (AMI). These studies, however, were performed before the contemporary widespread use of intracoronary stents and glycoprotien IIb/IIIa antagonists. METHODS: We prospectively compared the outcome of 130 consecutive elderly patients (aged > or =70 years) with ST-elevation AMI who were admitted to 2 similar neighboring medical centers. Patients were assigned to receive either thrombolytic therapy with accelerated tissue-type plasminogen activator (center I) or primary angioplasty with routine stenting (center II). RESULTS: Of the patients assigned to receive primary angioplasty, 91% underwent stenting. At 6 months, patients treated with primary angioplasty, compared with those treated with thrombolytic therapy, had a lower incidence of reinfarction (2% vs 14%, P =.053) and revascularization for recurrent ischemia (9% vs 61%, P <.001) and a significant reduction in the prespecified combined end point of death, reinfarction, or revascularization for recurrent ischemia (29% vs 93%, P <.01). Primary angioplasty remained an independent predictor of the triple combined end point after controlling for potential covariables (relative risk 0.63, 95% CI 0.38-0.84). Major bleeding complications were also significantly reduced in the primary angioplasty group (0% vs 17%, P =.03). CONCLUSIONS: Compared with thrombolysis, primary angioplasty with routine stenting in elderly patients with AMI is associated with better clinical outcomes and a lower risk of bleeding complications.

Aged↗
PubMed2003

Functional class in patients with heart failure is associated with the development of diabetes.

PURPOSE: Recent reports suggest that decreased functional capacity in patients with heart failure may be associated with abnormalities in glucose metabolism. We followed patients with coronary artery disease who participated in the Bezafibrate Infarction Prevention study to determine the incidence of diabetes by baseline functional status during a 7.7-year follow-up. METHODS: The sample comprised 2616 nondiabetic patients aged 45 to 74 years with a fasting blood glucose level <7 mmol/L (126 mg/dL). They were divided into three groups by New York Heart Association (NYHA) criteria: class I (n = 1986 patients), class II (n = 518), and class III (n = 112). The detection of a fasting blood glucose level > or =7 mmol/L during follow-up was defined as the criterion for the development of diabetes. RESULTS: The study groups had similar demographic and clinical characteristics, except that patients with symptomatic heart failure (NYHA class II or III) were more likely to have angina. During follow-up, diabetes developed in 259 patients (13%) in NYHA class I, 76 (15%) in class II, and 22 (20%) in class III (P for trend = 0.05). At the last visit, patients in NYHA class III were twice as likely (17% [n = 19]) to have fasting blood glucose levels > or =7 mmol/L as those in NYHA class I (7.8% [n = 154]) or class II (8.7% [n = 45]) (P = 0.005). In a multivariate analysis, NYHA class III was associated with a 1.7-fold (95% confidence interval [CI]: 1.1 to 2.6) increase in the rate of development of diabetes, but NYHA class II was not (hazard ratio = 1.0; 95% CI: 0.8 to 1.3). CONCLUSION: Among patients with coronary artery disease, advanced heart failure (NYHA class III) is associated with a significantly increased risk of developing diabetes during a 6- to 9-year follow-up.

Age Distribution↗
PubMed2002

Timing of aspirin administration as a determinant of survival of patients with acute myocardial infarction treated with thrombolysis.

Unlike thrombolytic agents, there are conflicting data regarding the time-dependent effect of aspirin treatment on outcome in acute myocardial infarction (AMI). We sought to evaluate the impact of timing of aspirin administration (before vs after thrombolysis) on mortality of patients with AMI. Our study included 1,200 patients with ST elevation AMI treated with thrombolysis. Early (n = 364) versus late (n = 836) users were defined as those receiving emergency aspirin before versus after initiation of thrombolysis, respectively. Time (median) from symptom onset to initiation of aspirin treatment was significantly shorter in early versus late users (1.6 vs 3.5 hours; p <0.001). There were no significant differences between the 2 groups with respect to baseline clinical characteristics. Early aspirin users were more likely to develop reischemia, to be treated with beta blockers, to be referred to coronary angiography, percutaneous transluminal coronary angioplasty, or coronary artery bypass graft surgery. Early users experienced lower mortality at 7 days (2.5% vs 6.0%, p = 0.01), 30 days (3.3% vs 7.3%, p = 0.008), and 1 year (5.0% vs 10.6%, p = 0.002) than late users. This survival benefit persisted for patients with and without previous aspirin therapy or revascularization and after adjustment for baseline characteristics and therapies at 7 days (odds ratio 0.36, 95% confidence interval 0.15 to 0.79), at 30 days (odds ratio 0.39, 95% confidence interval 0.17 to 0.82), and at 1 year (odds ratio 0.41, 95% confidence interval 0.21 to 0.74). Our study proposes a time-dependent benefit from aspirin in patients with AMI treated with thrombolysis.

Aged↗
PubMed2002

The incidence, pathophysiology, treatment and prognosis of Cheyne-Stokes breathing disorder in patients with congestive heart failure.

DEFINITION: Cheyne-Stokes respiration is a breathing disorder characterized by recurrent central sleep apneas, mainly during sleep, alternating with a crescendo-decrescendo pattern of tidal volume. PATHOPHYSIOLOGY AND PROGNOSIS: The pathophysiology of Cheyne-Stokes respiration, involving the cardiovascular, pulmonary and sympathetic nervous systems, is still not well understood. Although 50% of moderate to severe congestive heart failure patients suffer from significant Cheyne-Stokes respiration, studies been undertaken to determine the prevalence of this phenomenon and its implications regarding patients' life expectancy and quality of life were conducted only in recent years. Other studies suggest that Cheyne-Stokes respiration has a negative prognostic value upon congestive heart failure patients. TREATMENT: Novel therapeutic approaches have been attempted in order to treat Cheyne-Stokes respiration; they include oxygen delivery, various pharmaceutical treatments aimed to stabilize the ventilatory system and other pharmaceutical treatments aimed to improve the left ventricular ejection fraction. However, none of them was effective. OBJECTIVES: This review summarizes some of the current knowledge regarding Cheyne-Stokes respiration pathophysiology, prevalence, prognostic implication and available treatments.

Cardiotonic Agents↗
PubMed2002

Effect of elevated homocysteine levels on clinical restenosis following percutaneous coronary intervention.

Since hyperhomocysteinemia confers a prothrombotic effect and promotes proliferation of smooth muscle cells in response to vascular injury, it might be implicated in the pathogenesis of restenosis after percutaneous coronary intervention (PCI). Our study comprised 55 patients who underwent successful PCI in the acute myocardial infarction (AMI) course. Homocysteine levels were determined within 24 h of admission. During a 1-year follow-up, 16 patients (31%) underwent repeated coronary angiography for recurrent angina or re-infarction, which demonstrated re-narrowing of > or =50% at the qualifying PCI site (clinical restenosis). Irrespective of stent deployment, clinical restenosis was not associated with higher homocysteine levels (12 +/- 7 vs. 14 +/- 11 micromol/l, p = 0.77). There was no correlation between homocysteine levels and time to restenosis (r(2) = 0.06, p = 0.35). In conclusion, elevated homocysteine levels do not predict a higher incidence of restenosis after PCI.

Adult↗
PubMed2002

Oscillations in peripheral arterial tone in congestive heart failure patients: a new marker for Cheyne-Stokes breathing.

Cheyne-Stokes breathing (CSB), which is a prevalent finding in congestive heart failure (CHF) patients, has been shown to be of prognostic value. The oscillations in respiration were shown to be associated with oscillations in sympathetic nerve activation. We tested the hypothesis that the peripheral arterial tone (PAT) as measured by a novel finger plethysmograph can be used to detect CSB. Using a novel technique to measure the PAT, we monitored 10 patients with advanced CHF simultaneously with conventional polysomnographic recordings for either 1 or 2 nights. Records were scored for CSB during 3-min periods based on either respiratory effort and nasal-buccal airflow or on the PAT signal alone. The PAT sensitivity and specificity for the detection of periods containing CSB were 91 and 91% for the entire recording, 90.7 and 92.9% for non-REM sleep, 90.7 and 70% for REM sleep, and 73 and 97.3% for awake periods, respectively. PAT is a reliable marker of CSB in CHF patients. The novel finger plethysmograph can be used for screening and monitoring CSB.

Adult↗