Biomedical subjects

Jan Lukl

Publications and source records attributed to Jan Lukl.

13 recordsLinked to original sources

PubMed2006

Usefulness of bifocal pacing in patients with heart failure and intraventricular conduction delay.

BACKGROUND: Bifocal pacing (BFP) has been proposed as a feasible alternative to cardiac resynchronization therapy. AIM: To evaluate BFP in patients with severe heart failure and significant intraventricular conduction delay and to compare it with biventricular pacing (BVP). METHODS: Echocardiographic examination including TDI and invasive measurement of haemodynamics was performed under basal conditions, during BFP and during BVP. RESULTS: Fifty patients were included: 29 with ischaemic heart disease (IHD), 21 with idiopathic dilated cardiomyopathy (IDCM). LV dp/dt(max) increased during BFP compared to the basal state (13.4%, 95% CI 9.2-17.6%, p<0.0001) and a further increase was achieved during BVP (29.5%, 95% CI 23.7-35.4%, p<0.0001). A significant correlation was found between the distance of the right ventricular apical and outflow tract leads and percentage of dp/dt(max) increase in IDCM patients (r=0.72), but not in IHD patients. Interventricular mechanical delay (IVMD) decreased in BFP (43+/-22 ms vs. 53+/-31 ms, p=0.006), but BVP produced even shorter IVMD (22+/-19 ms, p<0.0001). In all patients, regional systolic contraction times were significantly shortened, corresponding with prolongation of the respective regional diastolic filling times during both BFP (p<0.05 for all segments) and BVP (p<0.001 for all segments). CONCLUSIONS: BFP improves LV haemodynamics by decreasing the inter- and intraventricular conduction delays. The leads in the right ventricle should be placed at the longest achievable distance. BVP is superior to BFP.

Aged↗

PubMed2006

Case report: Symptoms of advanced heart failure--a case for radiofrequency catheter ablation?

A sixty-year-old man with previous history of coronary artery disease was admitted due to progressive worsening of dyspnoea at exertion (NYHA III functional class) and no angina. Coronary angiography confirmed occlusion of the right coronary artery which was naturally bypassed by homocollaterals with TIMI 3 flow to the peripheral branches. The lesion was not technically suitable for percutaneous angioplasty. The left coronary artery was without stenosis. On echocardiography, both the left ventricle and the left atrium were dilated and hemodynamically significant mitral regurgitation was present. Surface ECG showed a left bundle branch block with repeated runs of monomorphic ventricular ectopic beats (PVC). Radiofrequency catheter ablation of the focus in the posteroseptal region of the left ventricle underneath the mitral valve was performed using electroanatomical mapping system. After the procedure, mitral regurgitation decreased and reverse remodeling of the left ventricle and the left atrium occurred with concomitant significant clinical improvement of the patient. The authors discuss several treatment strategies: mitral valve repair surgery combined with revascularization, implantation of a biventricular ICD system or elimination of the focus of monomorphic VT runs by radiofrequency catheter ablation as a possible causal approach in the treatment of PVC-induced cardiomyopathy.

Body Surface Potential Mapping↗

PubMed2006

Incidence of pericardial effusion in females stimulated in "in vitro fertilization" program.

AIMS: To evaluate the incidence of pericardial irritation in females after hormonal stimulation in in vitro fertilization program, and to set its clinical significance as a symptom of ovarian hyperstimulation syndrome (OHSS). PATIENTS: Thirty-nine females, aged 30 +/- 5 years (20-46), with a normal echo finding prior to hormonal stimulation. METHODS: Serial echocardiography: baseline A, in hCG application B, embryo-transfer C. RESULTS: Thirty-nine, 39, and 35 echocardiography examinations were done on A, B, and C respectively. On B, in 7 (17.9%) of 39 patients either new pericardial effusion "1," increased pericardial echogenicity "2," or both "3" were detected (4 patients, 2 patients, and 1 patient, i.e., 10.3%, 5.1%, and 2.6% respectively.). On C, in 8 of 35 patients (22.8 %) abnormalities were detected: "1" in 2 patients (5.7 %), "2" in 1 patient (2.9 %), and "3" in 5 patients (14.2 %). No clinical symptoms related to these findings were present. No OHSS occurred in these patients. On the contrary, clinical OHSS developed later in 2 patients, classified as medium degree (1 patient) and severe degree (1 patient)-both patients had negative echo during follow-up. CONCLUSION: Echocardiographic signs of mild pericardial irritation may appear also in patients with no clinical signs of OHSS. The incidence of these changes increases during stimulation procedure. Development of OHSS may not be preceded by the incidence of these warning signs. Consequently, routine echocardiographic examination during stimulation is not indicated, since significant pericardial effusion is rather a late sign of OHSS.

Adult↗

PubMed2005

Dramatically improved left ventricular function after biventricular pacemaker implantation--a case report.

A case study of a patient suffering from severe chronic congestive heart failure resulting from ischemic cardiomyopathy in whom a biventricular (BiV) pacing system was implanted is reported. After a 1-year follow-up, left ventricular (LV) ejection fraction improved dramatically from an initial 15% to 60%, left ventricular end-diastolic diameter decreased, as did left atrial dimension. Tissue Doppler data and acute hemodynamic measurements taken during the biventricular pacemaker implantation procedure are presented. The case represents an exceptional example of left ventricular reverse remodeling with practically normalized left ventricular function after 1 year of synchronized pacing.

Aged↗

PubMed2005

Postmortem anatomy of the coronary sinus pacing lead.

Biventricular pacing nowadays represents a recognized method of nonpharmacological treatment of severe congestive heart failure refractory to medication. A growing number of biventricular implants is likely to bring an increasing demand for the extraction of specially designed coronary sinus (CS) leads for left ventricular pacing. There is a lot of data regarding conventional pacing or defibrillation lead extractions, but only very limited experience with the CS lead extractions. We describe the pathological-anatomical findings of a woman who died after 26 months postimplantation due to refractory ventricular fibrillation with focus on the left ventricular pacing lead course and feasibility of extraction.

Aged↗

PubMed2005

Risk factors for cardiovascular diseases in physicians.

The aim of the study was to determine the prevalence of risk factors for cardiovascular diseases among physicians at a teaching hospital. In total, 203 men and 167 women were included in the study. The participants filled in a questionnaire; their height, weight, blood pressure, serum cholesterol and glucose levels were added. 19.2 % males and 13.8 % females were smokers, hypertension was diagnosed in 10 % of males and in 6.6 % of females, 52.2 % males and 17.4 % females were overweight, 37 % males and 43.1 % females had hypercholesterolemia. The above findings suggest that Czech physicians have more favourable values of all the studied cardiovascular diseases risk factors than the general Czech population. However, Czech physicians smoke more than those in other countries and their level of cardiovascular diseases risk factors is unsatisfactory and calls for further intensive prevention. Preliminary outcomes of the study repeated after two years show no positive trends as well as physicians' low willingness to actively participate in lowering cardiovascular diseases risk factors.

Adult↗

PubMed2004

Prevention of atrial fibrillation after cardioversion: results of the PAFAC trial.

AIMS: In patients with persistent atrial fibrillation (AF), the efficacy and safety of two anti-arrhythmic drugs in preventing the recurrence of AF after successful direct current (DC) cardioversion was prospectively assessed in a multi-centre double-blind, placebo-controlled, randomised trial using daily trans-telephonic monitoring. METHODS AND RESULTS: 1182 patients with persistent AF were prospectively enrolled, 848 patients were successfully cardioverted and then randomised to either sotalol (383 patients), quinidine plus verapamil (377 patients) or placebo (88 patients). The primary outcome parameter was AF recurrence or death. All patients received an event recorder (Tele-ECG) and had to record and transmit via telephone at least one ECG per day during follow-up. The mean follow-up period was 266 days. A total of 191,103 Tele-ECGs were recorded and transmitted. The primary outcome parameter (AF recurrence of any kind or death) was observed in 572 patients (67%) in whom at least one episode of AF recurrence was documented during follow-up, in 348 patients (41%) AF recurrence was persistent. The recurrence rates after one year for any AF were 83% for placebo, 67% for sotalol and 65% for quinidine plus verapamil, the latter being statistically superior to placebo but not different from sotalol. The recurrence rates for the secondary outcome parameter persistent AF were 77%, 49% and 38%, respectively. Quinidine plus verapamil was significantly superior to placebo and to sotalol. About 95% of all AF recurrences were initially detected in the daily Tele-ECG, about 70% of all AF recurrences occurred completely asymptomatic. Adverse events on sotalol and quinidine plus verapamil were comparable with the exception that all torsade de pointes tachycardias occurred on sotalol. CONCLUSION: Anti-arrhythmic treatment after DC cardioversion of persistent AF significantly decreases the recurrence rates of persistent AF compared to placebo with superiority of quinidine plus verapamil compared to sotalol. Symptoms were not reliable as clinical surrogates to detect episodes of AF.

Adolescent↗

PubMed2004

Triple-site pacing in patients with biventricular device-incidence of the phenomenon and cardiac resynchronization benefit.

BACKGROUND: In patients with biventricular pacing (BIV), triple-site pacing (TSP), i.e. standard biventricular cathodal pacing of the right and the left ventricle plus additional anodal capture of the right ventricle, is sometimes present. AIMS: To evaluate the incidence of TSP phenomenon, to examine TSP-related QRS changes, and to assess the effect of TSP on intraventricular resynchronization by means of tissue Doppler imaging (TDI). METHODS AND RESULTS: 23 patients with a first generation biventricular device (Medtronic 8040) and 16 patients with a new generation device (Medtronic 8042) were evaluated to look for the presence of TSP. TSP was found in 6 patients (26%) with the Medtronic 8040 (group I) and in 13 patients (81%) with the Medtronic 8042 device (group II). QRS duration decreased by 10 to 20 ms and QRS amplitude of leads I and aVL increased in almost all patients in group I during TSP modality. In group II, QRS morphology, duration and amplitude did not change as obviously. TDI analysis of the left ventricular (LV) basal segments showed significant shortening of the systole, together with a corresponding prolongation of the diastole, at the inferior wall of the LV, during TSP compared to standard BIV in all patients ( p < 0.01). Other LV segments did not show any change. Qualitative TDI electro-mechanical activation pattern of all LV segments improved in 22%, while it remained unchanged in 72%. CONCLUSIONS: TSP phenomenon can be identified in approximately a quarter of patients with the first-generation biventricular devices on the basis of the QRS morphology changes. In the second-generation biventricular pacemakers it can be demonstrated in the vast majority of patients. TSP may increase the effectiveness of cardiac resynchronization therapy by counteracting the regional activation delay located at the inferior wall of the LV.

Aged↗

PubMed2004

Endothelial damage and activation of the hemostatic system during radiofrequency catheter isolation of pulmonary veins.

AIMS: To determine the systemic thrombogenic effect of radiofrequency catheter isolation of the pulmonary veins (PVI) in the treatment of atrial fibrillation. METHODS AND RESULTS: We studied endothelial damage marker (von Willebrand factor [vWf]), fibrinolysis markers (tissue plasminogen activator [t-PA], plasminogen activator inhibitor-1 [PAI-1]) and coagulation activation markers (D-dimer [DD]) in 30 patients (pts) undergoing PVI. Heparin was administered continuously after double transseptal puncture in all pts. Concentrations of vWf and t-PA were significantly increased after accomplishing PVI compared to the baseline values, and elevated levels persisted 24 hours later ( p < 0.01). PAI-1 levels decreased following PVI compared to the baseline levels ( p = 0.02). PAI-1 levels normalized 24 hours after the procedure. DD increased continuously during the procedure with the peak following PVI ( p < 0.01). Higher DD concentrations persisted 24 hours later ( p = 0.02). In a multivariate analysis, total procedure time correlated significantly with the peak vWf and DD concentrations, while total RF energy dose correlated only with peak vWf ( r = 0.82). Time to heparin administration correlated with DD levels prior to the first RF pulse ( r = 0.83, p < 0.01) as well as after PVI ( r = 0.75, p < 0.01). A group of patients heparinized within the first hour of the PVI procedure had normal preablation DD levels and significantly mitigated DD levels following PVI compared to the group of patients heparinized later ( p < 0.01). CONCLUSIONS: Pulmonary vein ablations cause an increased systemic procoagulant state as reflected by fibrin turnover, fibrinolysis activation and endothelial perturbation. The activation of the coagulation cascade could be decreased by early heparin administration.

Adult↗

PubMed2004

Monocyte chemoattractant protein-1 in patients with peripheral arterial disease.

BACKGROUND: Chemokine-driven migration of inflammatory cells has been implicated in the pathogenesis of atherosclerotic conditions including peripheral arterial disease (PAD). Monocyte chemoattractant protein-1 (MCP-1) is elevated in patients with coronary artery disease and in hypertensive patients. This study therefore investigated MCP-1 in patients with PAD. METHODS: Serum MCP-1 was determined by enzyme-linked immunosorbent assay in 36 healthy, control subjects and in 19 patients with PAD. Statistical analysis utilised the Mann-Whitney test and Spearman correlation (p < 0.05). RESULTS: MCP-1 (pg/ml) was increased in patients compared with in controls (mean+/-standard error of the mean: PAD group, 748+/-60; control group, 459+/-27; p=0.0001). MCP-1 levels tended to decrease with progressing disease. From atherosclerosis risk factors, diabetes inclined to increase MCP-1 levels; hypertension had no effect. Serum MCP-1 correlated with cholesterol, triglycerides, low-density lipoprotein but not high-density lipoprotein. CONCLUSION: Elevation of MCP-1 in the circulation of PAD patients shown in the present pilot study implicates this CC chemokine ligand 2 in inflammatory processes contributing to PAD clinical symptomatology. Further investigations are necessary to evaluate whether MCP-1 can be used as a potential marker of peripheral arterial disease follow-up and/or prognosis.

Aged↗

PubMed2004

Short-term spectral analysis of heart rate variability during supine-standing-supine test in patients with paroxysmal atrial fibrillation.

The aim of the study was to assess the sympathovagal balance in group of 27 patients without significant structural heart disease after an attack of atrial fibrillation. The investigation was performed using spectral analysis of heart rate variability during examination under conditions of different orthostatic loads in single phases, called the supine-standing- supine test. The findings were compared with a group of healthy persons. These revealed a significantly decreased total spectral power (430.7 vs 1558.0 ms(2) supine1; 477.6 vs 1042,5 ms(2) standing; 567.5 vs 1948.5 ms(2) supine2), and spectral power of the high frequency spectral component (140.8 vs 619.3 ms(2) supine1; 96.2 vs 203.3 ms(2) standing; 186.3 vs 739.4 ms(2) supine2) in the studied group of patients in comparison with the control group.

Adult↗

PubMed2003

CC chemokine receptor (CCR)2 polymorphism in Czech patients with myocardial infarction.

Examining an association between myocardial infarction (MI) and the Val/Ile polymorphism in the gene for CC chemokine receptor (CCR)2 at the position 64 (CCR2-V64I), 122 MI Czech patients and 277 unrelated control (C) subjects were genotyped by PCR-SSP. The frequency of the VI genotype of CCR2-V64I was increased in MI patients in comparison with the control population (P=0.03). Further analysis revealed that relationship between the VI genotype and MI is specific only for females and, strikingly, this genotype was associated to an early MI onset (before or at the age of 50 years). Females with the VI genotype were seven times more prone to suffer from MI before 50 years than those with the VV genotype (P<0.01). If the VI genotype of the CCR2-V64I is indeed a risk factor for an earlier MI onset in females must be checked by independent studies in other centres and/or populations.

Case-Control Studies↗

PubMed2002

Assessment of spectral analysis of heart rate variability in patients with history of atrial fibrillation by means of age-dependent parameters.

Heart rate variability evaluation is a useful diagnostic tool for autonomic nervous balance assessment. The role of the autonomic nervous system in aetiology of atrial fibrillation is sometimes clear as a trigger from a patient's history, but mostly it acts as a modulating factor which is not easy to detect. The present study demonstrates results of spectral analysis of short-term heart rate variability during ortho-clinostatic tests processed by means of age-dependent parameters. An original telemetric system and a unique method for heart rate variability assessment, developed by the Faculty of Physical Culture, were applied for the first time to examine patients with the history of atrial fibrillation.

Adolescent↗