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Aleksandar N Nesković

Publications and source records attributed to Aleksandar N Nesković.

12 recordsLinked to original sources
PubMed2006

The fate of the radial artery conduit in coronary artery bypass grafting surgery.

Coronary artery bypass grafting (CABG) is the standard surgical procedure for the treatment of advanced coronary artery disease. CABG surgery has been demonstrated to improve symptoms and, in specific subgroups of patients, to prolong life. Despite its success, the long-term outcome of coronary bypass surgery is strongly influenced by the fate of the vascular conduits used. Impressive long-term disease-free patency rate of the left internal thoracic artery-left anterior descending coronary artery (LITA-LAD) graft, coupled with proven long-term survival benefits, has led to its becoming a 'golden standard' of CABG. Previous long-term studies have also shown unsatisfactory patency of saphenous vein grafts used for myocardial revascularization, compared with internal thoracic artery grafts. Thus, the use of arterial conduits has expanded beyond the internal thoracic arteries (ITAs) to include the right gastroepiploic artery, the inferior epigastric artery, and the radial artery. The assumption is that although the performance of one or two arterial ITA graft is superb, more arterial grafts should perform better in the long-term follow-up. Several studies concerning the use of the radial artery bypass grafts have documented excellent clinical results and satisfactory short-term as well as mid-term patency rates at restudy angiography, supporting its continued use as a bypass conduit. However, a note of caution concerning radial artery conduit patency rate have appeared in few recent reports. Thus, in this paper, we summarize the current evidence about the radial artery as a conduit in CABG surgery, with special emphasis on the clinical results.

Coronary Artery Bypass↗
PubMed2005

Right vs. left ventricular contractile reserve in one-year prognosis of patients with idiopathic dilated cardiomyopathy: assessment by dobutamine stress echocardiography.

AIM: To determine prognostic implications of the assessment of right (RV) vs. left ventricular (LV) contractile reserve with dobutamine echocardiography in patients with idiopathic dilated cardiomyopathy. METHODS AND RESULTS: Forty-eight consecutive patients (41 male, NYHA class III/IV 13 patients, LV ejection fraction 19+/-8%) were subjected to dobutamine stress echocardiography in incremental stages lasting 5 min each. Contractile reserve was defined as the difference between the values of LV ejection fraction and RV fractional area change obtained at peak dobutamine dose and the baseline values. Patients were followed for one year after enrollment for combined end-point of cardiac death, partial left ventriculectomy and hospitalization for congestive heart failure. During the follow-up 15/48 patients reached combined end-point. Patients who reached end-point had lower RV and LV contractile reserves (14+/-5 vs. 8+/-6%, p=0.0014, and 9+/-5 vs. 3+/-2%, p<0.001, respectively). Kaplan-Meier curves demonstrated that both LV and RV contractile reserves can identify patients with dismal prognosis (log rank=17.02 and log rank=14.66, respectively, p<0.001 for both). Multivariate analysis identified dobutamine induced change in LV functional reserve as the only independent predictor of combined end-point (beta=-0.63, p=0.0035). CONCLUSION: Both RV and LV contractile reserves can be used for prognostic stratification in patients with idiopathic dilated cardiomyopathy. It appears that dobutamine induced change in LV functional reserve may better identify patients with dismal prognosis.

Adult↗
PubMed2005

Relation of myocardial histomorphometric features and left ventricular contractile reserve assessed by high-dose dobutamine stress echocardiography in patients with idiopathic dilated cardiomyopathy.

BACKGROUND: This study was designed to determine the relationship between histomorphometric features and contractile reserve assessed by high-dose dobutamine stress echocardiography in patients with idiopathic dilated cardiomyopathy. METHODS: Twenty-four consecutive patients (21 men, aged 43.4+/-8.7 years) with idiopathic dilated cardiomyopathy underwent dobutamine stress echocardiography. Wall motion score index, ejection fraction, cardiac power output and end-systolic pressure/volume ratio were used as indices of left ventricular contractility. Left ventricular endomyocardial biopsy specimens (3-5 per patient) were routinely processed and stained with Masson trichrome, interstitial fibrosis and myocyte diameter were calculated quantitatively. RESULTS: Myocyte diameter and interstitial fibrosis showed strongest correlation with change in wall motion score index (r=-0.667, p<0.001, and r=-0.567, p=0.004, respectively), followed by change in ejection fraction (r=-0.603, p=0.002, and r=-0.467, p=0.021, respectively). Interstitial fibrosis showed no correlation with change of cardiac power output and end-systolic pressure/volume ratio, whereas myocyte diameter was associated with change of both indices (r=-0.565, p=0.004, and r=-0.455, p=0.025). CONCLUSIONS: Contractile reserve elicited by high-dose dobutamine is strongly related to the degree of histological disruption in patients with idiopathic dilated cardiomyopathy.

Adult↗
PubMed2005

Semiquantitative histomorphometric analysis of myocardium following partial left ventriculectomy: 1-year follow-up.

BACKGROUND: Although partial left ventriculectomy (PLV) may have beneficial clinical effects in patients with dilated cardiomyopathy (DCM), there are no reports on effects of PLV on myocardial histology. The objective of this study was to assess histological properties of the LV myocardium 1 year following PLV as compared to histology at the time of the operation. METHODS: The study group consisted of 15 consecutive PLV survivors, predominantly male (13/15), aged 45+/-12 years. Surgical specimens and endomyocardial biopsies, taken 12 months postoperatively, were processed routinely and stained with Masson-trichrome. The following morphometric parameters were assessed semiquantitavely: (1) degree of hypertrophy and attenuation; (2) nuclear evidence of hypertrophy; (3) myofibrillar volume fraction; (4) degree of degenerative vacuolar changes; and (5) fibrosis volume fraction. RESULTS: Both New York Heart Association (NYHA) functional class and ejection fraction (EF) improved 12 months following surgery as compared to preoperative values (2.40+/-0.69 vs. 3.33+/-0.49, p<0.001, and 33.21+/-12.05% vs. 20.21+/-9.07%, p<0.001, respectively). Morphometric analysis demonstrated postoperative decrease in the degree of attenuation as compared to preoperative values (1.40+/-0.51 vs. 2.47+/-0.64, p<0.01), as well as a decrease in fibrosis volume fraction (2.07+/-0.80 vs. 2.67+/-0.49, p<0.001) and nuclear hypertrophy (1.27+/-0.46 vs. 1.67+/-0.62, p<0.05). On the other hand, postoperative increase in myofibrillar volume fraction (1.87+/-0.61 vs. 1.40+/-0.61, p<0.01) was noted. CONCLUSION: One year postoperatively, PLV has favourable effects on myocardial morphology that parallels improvement in the patient's functional status and LV systolic function.

Adult↗
PubMed2004

Hyperbaric oxygen treatment does not affect left ventricular chamber stiffness after myocardial infarction treated with thrombolysis.

BACKGROUND: It has been shown that transient increase in left ventricular stiffness, assessed by Doppler-derived early filling deceleration time, occurs during the first 24 to 48 hours after myocardial infarction but returns to normal within several days. It has been reported that hyperbaric oxygen treatment has a favorable effect on left ventricular systolic function in patients with acute myocardial infarction treated with thrombolysis. However, there are no data on the effects of hyperbaric oxygen on diastolic function after myocardial infarction. METHODS: To assess acute and short-term effects of hyperbaric oxygen on left ventricular chamber stiffness, we studied 74 consecutive patients with first acute myocardial infarction who were randomly assigned to treatment with hyperbaric oxygen combined with streptokinase or streptokinase alone. After thrombolysis, patients in the hyperbaric oxygen group received 100% oxygen at 2 atm for 60 minutes in a hyperbaric chamber. All patients underwent 2-dimensional and Doppler echocardiography 1 (after thrombolysis), 2, 3, 7, 21, and 42 days after myocardial infarction. RESULTS: Patient characteristics, including age, sex, risk factors, adjunctive postinfarction therapy, infarct location, and baseline left ventricular volumes and ejection fraction, were similar between groups (P >.05 for all). For both groups, deceleration time decreased nonsignificantly from day 1 to day 3 and increased on day 7 (P <.001, for both groups), increasing nonsignificantly subsequently. The E/A ratio increased in the entire study group throughout the time of study (P <.001, for both groups). The pattern of changes of deceleration time was similar in both groups (P >.05 by analysis of variance), as was in subgroups determined by early reperfusion success. CONCLUSIONS: These data in a small clinical trial do not support a benefit of hyperbaric oxygen on left ventricular diastolic filling in patients with acute myocardial infarction treated with thrombolysis.

Aged↗
PubMed2003

Comparative value of single-beat load-independent contractility indices in dilated cardiomyopathy and mitral regurgitation.

OBJECTIVE: We sought to compare single-beat estimates of contractility indices. METHODS: Echocardiography was performed for 6 control patients, 8 patients with dilated cardiomyopathy, and 9 patients with mitral regurgitation (MR). Left ventricular volume waveform, outflow tract velocities, and mitral annulus velocities were recorded with carotid tonometry. Numeric simulations were used to generate the same data while varying contractility, compliance, and MR. Estimates of elastance (normalized systolic and bilinearly approximated), preload-recruitable stroke work, and preload-adjusted maximal power were calculated. RESULTS: Normalized systolic and bilinearly approximated elastance were decreased in patients with dilated cardiomyopathy (P <.005 for both) and MR (P =.0002 and.02, respectively). Preload-recruitable stroke work and preload-adjusted maximal power were decreased in patients with dilated cardiomyopathy only (P <.005 for both). Simulations confirmed that these differences are a result of dissimilar behavior of estimates if MR or compliance change. CONCLUSIONS: Single-beat indices are decreased in dilated cardiomyopathy, but in MR show dissimilar behavior.

Adult↗
PubMedDate not supplied

[Atherosclerosis plaque regression].

INTRODUCTION: The natural history of atherosclerosis can be assessed using different methods including quantitative coronary angiography, intravascular ultrasound, B-mode ultrasound, electron-beam computed tomography and magnetic resonance imaging. REGRESSION OF ATHEROSCLEROSIS: Although the first investigations regarding effects of low cholesterol diet on atherosclerosis progression in animals were performed almost 100 years ago, researches on potential induction of atherosclerosis regression in humans began only recently, in the past 20 years. To date, many studies assessing different drugs and study protocols on natural evolution of atherosclerosis have been performed. They include use of diet and physical activity, different hypolipemic drugs, especially statins, ACE inhibitors, calcium channel blockers, hormone replacement therapy, antioxidants, and recently, use of recombinant apolipoproteins. STATINS AND ATHEROSCLEROSIS: It has been established that statins given to patients with, or even without verified coronary artery disease, slow progression of atherosclerosis. These effects of statins are likely due to a combination of their metabolic and pleiotropic properties and might in part explain the positive effects of these drugs on overall cardiovascular mortality and morbidity. Furthermore, applied in high doses, these drugs may induce real atherosclerosis regression, especially in asymptomatic patients in the early stages of the disease.

Atherosclerosis↗
PubMedDate not supplied

[Head-to-head comparison of clinical, biochemical and functional effects of fosinopril and enalapril in patients with systolic heart failure].

INTRODUCTION: The aim of this study was to evaluate short-term clinical, biochemical and functional effects of fosinopril versus enalapril in patients with heart failure. MATERIAL AND METHODS: 59 consecutive patients (mean age 57 +/- 8 years, EF 18.9 +/- 6.3%, NYHA III or IV class 19/59) were randomized to receive fosinopril or enalapril for three months. All patients underwent echocardiography, metabolic testing, and a 6-minute walk test and completed the Minnesota questionnaire on inclusion and three months later. Additionally, serum creatinine, BUN, total cholesterol and triglycerides were measured. Kaplan-Meier curve was created to assess event-free survival for cardiac death and hospitalization for heart failure. RESULTS: There was no statistically significant difference in event-free survival between patients on fosinopril and enalapril (86.7% vs. 82.8%, log rank 4.21 p=0.43). However, time to the event was longer in patients on fosinopril (77.0 +/- 25.35 vs. 40.2 +/- 6.8 days, p=0.04). At the end of the study, no difference between fosinopril and enalapril group existed with respect to maximal oxygen consumption (20.90 +/- 4.47 vs. 20.89 +/- 6.86 ml/kg/min), ejection fraction (20.5 +/- 7.4 vs. 21.4 +/- 7.8%), distance during the 6-minute test walk (313 +/- 74 vs. 352 +/- 129 meters) and quality of life (23.8 +/- 15.8 vs. 25.6 +/- 20.3 points), but patients on enalapril had higher creatinine (99 +/- 13 vs. 113 +/- 17 micromol/L, p=0.002) and BUN (7.28 +/- 1.7 vs. 8.89 +/- 2.39 mmol/L, p=0.01) levels. Increase in fosinopril dose during the study was higher than increase in enalapril dose (24.1% +/- 23.8% vs. 9.5 +/- 24.5%, p=0.04). CONCLUSIONS: Fosinopril and enalapril have similar short-term effects on event-free survival, ejection fraction, functional capacity and quality of life in patients with heart failure. Patients on fosinopril presented with longer survival without event and had lower creatinine and BUN at the end-of the follow-up. Additionally, fosinopril can be easily titrated to the maximum therapeutic dose.

Angiotensin-Converting Enzyme Inhibitors↗
PubMedDate not supplied

[Outcome and prognosis of surgical treatment in patients with severe aortic stenosis with respect to the duration and severity of associated aortic regurgitation].

INTRODUCTION: It is not clear whether associated aortic regurgitation (AR) should be regarded as a risk factor in patients undergoing surgery for severe aortic stenosis (AS). Some authors have suggested that morbidity and mortality are increased in these patients as compared to patients operated for pure AS, whereas others have found no difference of the outcome and prognosis between these groups. OBJECTIVE: This study made an attempt to compare the outcome and prognosis following the surgical intervention in patients with severe AS and associated AR and those operated for pure AS, as well as to determine predictive value of clinical, functional and echocardiographic data for the outcome of surgery. METHODS: Study population consisted of 122 consecutive patients operated at Dedinje Cardiovascular Institute during 1999 due to severe AS, defined as mean gradient over aortic valve >30 mmHg. The patients were divided into AS group (63 patients with AS without AR or with mild AR) and AS+AR group (59 patients with AS and moderate, severe or very severe AR). The patients were subjected to control clinical, functional and echocardiographic examinations 12 and 18 months following the surgery. RESULTS AND DISCUSSION: Preoperatively, the patients in AS group were older and had coronary artery disease more frequently, whereas patients in AS+AR group had higher left ventricular volumes and mass. Preoperative NYHA class, ejection fraction, mean gradient over aortic valve, type and size of the implanted mechanical prosthesis, and the incidence of associated coronary artery bypass surgery were similar between the groups. Similarly, the operative mortality was similar in AS and AS+AR groups (1.6% vs 8.5%, respectively, p=0.11). Twelve months postoperatively, there were no difference of average NYHA class and NYHA class III/IV between the groups. The patients in AS+AR group were unable to walk >300 meters on 6 minute walk test more frequently than those in AS group (64% vs. 36%, respectively; p=0.043). Eighteen months postoperatively, NYHA class III/IV was found more frequently in AS+AR than in AS group (26% vs. 8%, respectively; p=0.0343). In patients with associated AR, there was no difference of NYHA class with respect to the severity of AR (p=0.815). Multivariate analysis found the association of more than mild AR as an independent predictor of poor functional capacity, irrespective of its severity. CONCLUSION: Patients with severe AS and associated AR have poorer postoperative functional capacity as compared to patients operated for pure AS.

Aortic Valve Insufficiency↗
PubMedDate not supplied

[Comparison of prognostic value of high-dose dobutamine stress-echocardiography and exercise testing in patients with idiopathic dilated cardiomyopathy].

INTRODUCTION: It is of the utmost importance to make an accurate assessment of prognosis in patients with idiopathic dilated cardiomyopathy. Both high-dose dobutamine stress-echocardiography and exercise testing have been used for prognostic stratification of these patients. OBJECTIVE: To make head-to-head comparison of high-dose dobutamine stress-echocardiography and exercise testing in prognostic stratification of patients with idiopathic dilated cardiomyopathy. METHODS: A total of 63 consecutive patients (55 men, mean age 50.1 +/- 9.6 years, mean ejection fraction 19.2 +/- 8.4%) with idiopathic dilated cardiomyopathy, left ventricular end-diastolic diameter >60mm, ejection fraction <35%, and adequate echocardiographic window have been studied. Dobutamine stress echocardiography was performed using 5, 10, 20, 30 and 40 mcg/kg/min infusions, in progressive stages lasting 5 minutes each. Wall motion score index and ejection fraction were considered the indices of the left ventricular contractility. Contractile reserve was defined as the difference between the values of these indices obtained at peak dobutamine dose during the test and the baseline values. Exercise testing was performed as supine bicycle ergometry in progressive stages of 25 W lasting 120 seconds each. Patients were followed one year for combined end-point consisting of cardiac death, partial left ventriculectomy and hospitalization for congestive heart failure. RESULTS: Out of 61, 19 (31%) patients met combined end-point during follow-up [cardiac death in 6/61 (10%), partial left ventriculectomy in 4/61 (7%) and hospitalization for heart failure in 9/61 (15%) patients]. Kaplan-Meier survival analysis demonstrated that dobutamine-induced change of wall motion score index was the best parameter for separation of patients in terms of prognosis during the follow-up (log rank=25.34, p<0.001), followed by change of ejection fraction (log rank=16.83, p<0.001) and duration of exercise testing (log rank 13.85, p=0.002). Cox model identified dobutamine-induced change of wall motion score index as the only independent predictor (p<0.001) of combined end-point during one-year follow-up. DISCUSSION: There is a number of studies dealing with the left ventricular contractile indices. These studies are different with respect to studied population, method used to elicit the left ventricular contractile response and the indices of contractile reserve. A number of studies has suggested that the amount of pharmacologically or physically induced change of wall motion score index and ejection fraction can identify patients with dismal prognosis. Peak oxygen consumption is traditionally considered the most accurate prognostic index, but its usefulness has been recently questioned. Our data suggest that high-dose dobutamine stress-echocardiography may be superior to exercise testing for prognostic stratification of patients with idiopathic dilated cardiomyopathy. The reasons for such observation are not clear, but it can be hypothesized that this may be due to multifactorial nature of the exercise tolerance. The most serious potential drawback of methodology is that, because of technical limitations, we did not test peak oxygen consumption in our patients, but since it has been shown that oxygen consumption correlates well with the duration of exercise, we believe that our methodology is valid. CONCLUSION: Both high-dose dobutamine stress-echocardiography and exercise testing can identify patients with dismal prognosis during one-year follow-up, but it appears that dobutamine stress-echocardiography may yield better prognostic significance.

Cardiomyopathy, Dilated↗
PubMedDate not supplied

[Effect of thrombolytic therapy on occurrence of complex ventricular arrhythmias in the late hospitalization period in acute myocardial infarct: relation with long-term remodeling of the left ventricle].

BACKGROUND: The impact of thrombolytic therapy on the incidence of complex ventricular arrhythmias is not yet clarified. The aim of this study was to investigate the impact of thrombolytic therapy on the incidence of complex ventricular arrhythmias, as well as long term association between complex ventricular arrhythmias and left ventricular remodelling, and their impact on five-year lethality. METHODS: Ninety seven consecutive patients with first acute myocardial infarction (streptokinase was administered in 58 patients), underwent 24-hours Holter monitoring at discharge. Ventricular arrhythmias were classified according to Lown classification, and patients were grouped into the group with simple ventricular arrhythmias (Lown class 0 to 2), and the group with complex ventricular arrhythmias (Lown class 3 to 5). Echocardiography was performed at discharge, and six and twelve months after the infarction. Left ventricular volume indexes and ejection fraction was determined using Simpson's biplane formula. RESULTS: In patients with complex ventricular arrhythmias left ventricular volume indexes were higher and ejection fraction was lower throughout the study, whereas wall motion score index was higher one year after the infarction. On the other hand, these variables were similar throughout the follow-up within the groups of patients with and without complex ventricular arrhythmias who received thrombolytic therapy. The incidence of complex ventricular arrhythmias was similar in thrombolyzed and non-thrombolyzed patients (11/58 vs. 5/39). There was no difference in five year lethality between patients with and without complex ventricular arrhythmias (4/16 vs. 13/81 patients). CONCLUSION: Our data indicated that left ventricular remodelling in patients with complex ventricular arrhythmias was not progressive after hospital discharge. The presence of complex ventricular arrhythmias was not associated with the increased five-year lethality, despite of more pronounced left ventricular remodelling. It occurred that thrombolysis per se had no influence on the incidence of complex ventricular arrhythmias in the late hospital phase after the first acute myocardial infarction.

Arrhythmias, Cardiac↗