Biomedical subjects

Jaroslav Meluzín

Publications and source records attributed to Jaroslav Meluzín.

6 recordsLinked to original sources

PubMed2006

Autologous transplantation of mononuclear bone marrow cells in patients with acute myocardial infarction: the effect of the dose of transplanted cells on myocardial function.

BACKGROUND: Despite the reports on successful treatment of acute myocardial infarction using autologous mononuclear bone marrow cell transplantation, many unresolved questions still remain. We studied the impact of the dose of transplanted cells on myocardial function and perfusion. METHODS: Sixty-six patients with a first acute myocardial infarction were randomized into 3 groups. Two groups were intracoronarily given mononuclear bone marrow cells in either higher (10(8) cells, higher cell dose [HD] group, n = 22) or lower (10(7) cells, lower cell dose [LD] group, n = 22) doses. Twenty-two patients without cell transplantation served as a control (C) group. RESULTS: At 3 months of follow-up, the baseline peak systolic velocities of longitudinal contraction of the infarcted wall of 5.2, 4.5, and 4.3 cm/s in C, LD, and HD groups increased by 0.0, 0.5 (P < .05 vs C group), and 0.9 cm/s (P < .05 vs LD group, P < .01 vs C group), respectively, as demonstrated by Doppler tissue imaging. Baseline left ventricular ejection fractions of 42%, 42%, and 41% in C, LD, and HD groups increased by 2%, 3%, and by 5% (P < .05 vs group C), respectively, as assessed by the gated technetium Tc 99m sestamibi single photon emission computed tomography. CONCLUSIONS: Mononuclear bone marrow cell transplantation improves regional myocardial function of the infarcted wall in a dose-dependent manner.

Bone Marrow Transplantation↗

PubMed2006

The role of quantitative Tc-99m-MIBI gated SPECT/F-18-FDG PET imaging in the monitoring of intracoronary bone marrow cell transplantation.

BACKGROUND: A lot of unresolved questions still exist concerning the exact mechanism of the beneficial effects of bone marrow cell (BMC) transplantation for myocardial regeneration. The aim of this communication is to report the cases of patients with and without post-transplantation left ventricular function improvement. MATERIAL AND METHODS: To this study we included consecutive patients with irreversible damage after a first acute ST-elevation myocardial infarction treated by coronary angioplasty with stent implantation. The irreversible damage was identified by dobutamine echocardiography and confirmed by rest gated Tc-99m-MIBI gated SPECT and in the majority of patients by F-18-FDG PET imaging as well. Using 4D-MSPECT software, we quantified MIBI/FDG uptake and gated SPECT left ventricular ejection fraction, end-diastolic/end-systolic volumes (LVEF, EDV/ESV) before BMC therapy and 3 months later. RESULTS: The results obtained in the initial group of patients in this study (27 patients in the BMC treated group, 16 patients in the control group) have been published previously [Eur J Nucl Med 2005; 32 (Suppl 1 ): S46]. Among the BMC group, we identified 13 responders to therapy with average LVEF improvement from 43.3% +/- 11% to 51.4% +/- 10.4% and EDV/ESV improvement from 145 ml/84 ml to 133 ml/67 ml. The remaining 14 patients were non-responders to therapy with no significant change in LVEF (39.1% +/- 8.1% versus 39.8% +/- 7.4%), the EDV/ESV increased from 166 ml/105 ml to 188 ml/116 ml. Responders to the cell therapy had prevailing MIBI uptake in the range of 31-50% of maximum in the infarction territory. On the other hand, non-responders to BMC therapy had prevailing MIBI uptake in the range of 0-30% of maximum. Two cases are presented in this report. CONCLUSIONS: Further studies with a larger cohort of patients would be helpful to evaluate our findings. We observed strong interindividual differences in the effectiveness of the cell therapy. Prevailing residual MIBI uptake in the range of 31-50% of maximum was in the subgroup of responders to the cell therapy.

Adult↗

PubMed2005

Right ventricular dysfunction in chronic heart failure patients.

AIM: To evaluate any differences in haemodynamic and echocardiographic parameters in patients with both left (LV) and right ventricular (RV) systolic dysfunction and in patients with isolated LV systolic dysfunction. STUDY GROUP: One hundred patients with RV systolic dysfunction defined as peak velocity of tricuspid annular motion in systole (Sa)<11.5 cm/s, and 55 patients without RV systolic dysfunction Sa>11.5 cm/s. All patients had LV systolic dysfunction, LV ejection fraction (EF) below 40%, NYHA II-IV. METHODS: LV diameters, volumes and EF were measured by echocardiography. Patients underwent tissue Doppler imaging (TDI) of tricuspid annular motion with measurement of peak systolic velocity (Sa), peak early (Ea) and peak late (Aa) diastolic velocities. Right heart catheterization was also performed. RESULTS: Patients with RV systolic dysfunction did not differ from those without RV systolic dysfunction in terms of LV function. Patients with RV systolic dysfunction had larger RV dimension 30.6+/-5.8 vs. 33.9+/-6.7 mm, p<0.002. The patients with RV systolic dysfunction had higher values on right heart catheterization: MPAP 29.6+/-12.1 vs. 24.9+/-11.4 mm Hg, p<0.02, PCWP 20.8+/-10.0 vs. 17.3+/-9.3 mm Hg, p<0.03, PVR 189.9+/-123.3 vs. 137.7+/-94.9 dyn s cm(-5), p<0.008, CVP 7.7+/-5.6 vs. 5.1+/-3.9 mm Hg, p<0.002. The patients with RV systolic dysfunction had more pronounced diastolic dysfunction measured by TDI: Ea 9.9+/-2.3 vs. 11.4+/-2.5 cm/s, p<0.0001 and Aa 13.1+/-4.0 vs. 16.5+/-4.7 cm/s, p<0.000007. CONCLUSION: Patients with heart failure and both left and right ventricular systolic dysfunction showed more serious findings on central haemodynamics as well as more pronounced right ventricular diastolic dysfunction than those with isolated left ventricular systolic dysfunction.

Female↗

PubMed2005

Comparison of acoustic densitometry and dobutamine echocardiography for an assessment of myocardial viability.

AIM: The aim of this study has been to compare acoustic densitometry and dobutamine echocardiography for an assessment of myocardial viability. METHODS AND RESULTS: Thirty-four patients with coronary artery disease and dysfunctional myocardial segments, who were referred for myocardial revascularization, underwent a viability assessment using low-dose dobutamine echocardiography and acoustic densitometry. Results of the two techniques were compared to follow-up resting echocardiography. This follow-up examination was performed at a mean of 3 months after successful revascularization in order to assess the recovery of function in revascularized, initially dysfunctional segments. Echocardiography was performed in standard views using 16-segment model of the left ventricle. Viable myocardium was identified by the augmentation of systolic thickening of an abnormal segment by at least one grade during dobutamine infusion and by the value of the maximal amplitude of cyclic variation of integrated backscatter. Acoustic densitometry had the sensitivity and specificity to predict functional recovery 90% and 77%, respectively. Dobutamine echocardiography had the sensitivity and specificity to predict contractile reserve 83% and 81%, respectively. The results were statistically comparable. Concordance between these methods was 80%. CONCLUSION: Acoustic densitometry and dobutamine echocardiography did not statistically differ in the prediction of functional recovery dysfunctional myocardial segments after revascularization.

Acoustics↗

PubMed2003

Prognostic importance of the quantification of myocardial viability in revascularized patients with coronary artery disease and moderate-to-severe left ventricular dysfunction.

The aim of this study was to assess the prognostic value of the amount of dysfunctional but viable myocardium in revascularized patients with coronary artery disease and left ventricular dysfunction. To quantify the amount of dysfunctional but viable myocardium, low-dose dobutamine echocardiography was performed. The wall motion was scored using a 16-segment model. The dysfunctional segments were defined as viable if they exhibited functional improvement of at least 1 grade with any dose of dobutamine, or only worsening with dobutamine infusion. Two hundred and twenty patients were revascularized and followed-up for a mean period of 33+/-23 months (range, 0-86) for cardiac-related death and hospitalization for heart failure. Standard follow-up echocardiography was performed 3-6 months after revascularization. Receiver operating characteristic curve analysis identified six dysfunctional but viable segments as the optimal cutoff value for discriminating patients with and without risk of cardiac events. Thirty-eight patients exhibited a large amount of dysfunctional but viable myocardium (>or=6 segments, group A), 103 patients had a small amount of dysfunctional but viable myocardium (2-5 segments, group B), and 79 patients were found to have dysfunctional myocardium irreversibly damaged (group C). Similar baseline left ventricular ejection fractions of 36+/-4, 34+/-5, 35+/-5% in groups A, B, and C increased to 46+/-6% (P<0.01 versus baseline and versus groups B and C), to 39+/-5% (P<0.01 versus baseline and group C), and to 36+/-7% (P<0.01 versus baseline), respectively, after revascularization. The greatest functional improvement after revascularization in group A patients was accompanied by a lower frequency of cardiac events during follow-up (1 vs. 27 in group B, P<0.01, and versus 18 in group C, P<0.01) and by a better cardiac event-free survival according to Kaplan-Meier survival analysis (P<0.01 versus groups B and C, respectively). In conclusion, in revascularized patients with coronary artery disease and moderate-to-severe left ventricular dysfunction, the presence of >or=6 dysfunctional but viable segments identifies patients with the best prognosis.

Adult↗

PubMed2003

Prognosis of patients with chronic coronary artery disease and severe left ventricular dysfunction. The importance of myocardial viability.

BACKGROUND AND AIM: The choice of optimal treatment strategy in patients with coronary artery disease (CAD) and severe left ventricular (LV) dysfunction is often difficult. The aim of this study was to compare long-term results of patients with chronic CAD, severe heart failure and a defined scope of myocardial viability treated with coronary revascularization, heart transplantation, or kept on medical therapy. METHODS: From 1993 to 2000, viability evaluation using low-dose dobutamine echocardiography was performed in 124 patients with CAD and LV ejection fraction <or=30%. The dysfunctional myocardial segments were defined as viable if they exhibited improvement in their thickening at any dose of dobutamine or worsening without initial improvement. The patients were divided into five groups and followed up for a mean period of 27+/-23 months. Group A consisted of 39 patients with viability (at least two dysfunctional but viable segments) who were revascularized. Group B consisted of 29 patients with viability treated medically. Groups C (n=23) and D (n=22) comprised patients with non-viable dysfunctional myocardial segments who were revascularized or kept on medical therapy, respectively. Eleven patients referred for heart transplantation after dobutamine echocardiography and 62 patients with ischemic cardiomyopathy transplanted in the same time interval were included in the group of transplanted patients (Group E). RESULTS: The Kaplan-Meier survival analysis demonstrated a significantly better survival of group A patients as compared with group B patients (P<0.05). The prognostic benefit of revascularization in patients with viability was not manifested until 3 years after the procedure. At 5 years, survival in groups A, B, C, D and E was 89, 60, 67, 50 and 78%, respectively. CONCLUSION: In patients with CAD, severe LV dysfunction, and the evidence of viability in dysfunctional myocardium, coronary revascularization improves survival. At least 3-years follow-up is necessary to objectively assess the prognostic effect of coronary revascularization.

Adrenergic beta-Agonists↗