Chronic performance of a leadless cardiac pacemaker: 1-year follow-up of the LEADLESS trial.

BACKGROUND: A leadless cardiac pacemaker (LCP) system was recently introduced to overcome lead-related complications of conventional pacing systems. To date, long-term results of an LCP system are unknown. OBJECTIVES: The aim of this study was to assess the complication incidence, electrical performance, and rate response characteristics within the first year of follow-up of patients implanted with an LCP. METHODS: We retrospectively assessed intermediate-term follow-up data for 31 of 33 patients from the LEADLESS trial cohort who had an indication for single-chamber pacing and received an LCP between December 2012 and April 2013. RESULTS: The mean age of the cohort was 76 ± 8 years, and 65% were male. Between 3 and 12 months of follow-up, there were no pacemaker-related adverse events reported. The pacing performance results at 6- and 12-month follow-up were, respectively, as follows: mean pacing threshold (at a 0.4-ms pulse width), 0.40 ± 0.26 V and 0.43 ± 0.30 V; R-wave amplitude 10.6 ± 2.6 mV and 10.3 ± 2.2 mV; and impedance 625 ± 205 Ω and 627 ± 209 Ω. At the 12-month follow-up in 61% of the patients (n = 19 of 31), the rate response sensor was activated, and an adequate rate response was observed in all patients. CONCLUSIONS: The LCP demonstrates very stable performance and reassuring safety results during intermediate-term follow-up. These results support the use of the LCP as a promising alternative to conventional pacemaker systems. Continued evaluation is warranted to further characterize this system. (Evaluation of a New Cardiac Pacemaker; NCT01700244).

Permanent leadless cardiac pacing: results of the LEADLESS trial.

BACKGROUND: Conventional cardiac pacemakers are associated with several potential short- and long-term complications related to either the transvenous lead or subcutaneous pulse generator. We tested the safety and clinical performance of a novel, completely self-contained leadless cardiac pacemaker. METHODS AND RESULTS: The primary safety end point was freedom from complications at 90 days. Secondary performance end points included implant success rate, implant time, and measures of device performance (pacing/sensing thresholds and rate-responsive performance). The mean age of the patient cohort (n=33) was 77±8 years, and 67% of the patients were male (n=22/33). The most common indication for cardiac pacing was permanent atrial fibrillation with atrioventricular block (n=22, 67%). The implant success rate was 97% (n=32). Five patients (15%) required the use of >1 leadless cardiac pacemaker during the procedure. One patient developed right ventricular perforation and cardiac tamponade during the implant procedure, and eventually died as the result of a stroke. The overall complication-free rate was 94% (31/33). After 3 months of follow-up, the measures of pacing performance (sensing, impedance, and pacing threshold) either improved or were stable within the accepted range. CONCLUSIONS: In a prospective nonrandomized study, a completely self-contained, single-chamber leadless cardiac pacemaker has shown to be safe and feasible. The absence of a transvenous lead and subcutaneous pulse generator could represent a paradigm shift in cardiac pacing. CLINICAL TRIAL REGISTRATION URL: http://clinicaltrials.gov. Unique identifier: NCT01700244.

[Early repolarisation syndrome and idiopathic ventricular fibrillation]. / Syndrom casné repolarizace a idiopatická fibrilace komor.

Syndrome of early repolarisation is a relatively not common electrocardiographic pattern with typically elevated J wave in most of the cases in lead II, III, aVF and V3-V6. There is increasing evidence that the early repolarisation might be associated with increased risk of sudden cardiac death in otherwise healthy individuals. Early repolarisation ECG pattern in inferolateral leads is associated with sudden death in younger otherwise healthy individuals. Identification of this risky group based on pure ECG criteria is still challenging but it must be considered in individuals with family history of sudden cardiac death or cardiac arrest.

N-terminal pro B-type natriuretic peptide as prognostic marker for mortality in coronary patients without clinically manifest heart failure.

Brain natriuretic peptide (BNP) and its inactive N-terminal fragment (NT-proBNP) are strong prognostic markers in patients with manifest heart failure and acute coronary syndromes. We aimed to establish the association between NT-proBNP and all-cause mortality in patients with stable chronic coronary heart disease. Three-hundred-eighty-five patients, 6-24 months after acute coronary syndrome or coronary revascularisation, but without history or symptoms of chronic heart failure, were included into the cohort study. The NT-proBNP was measured at baseline and all-cause mortality was ascertained after more than 6 years of follow-up. Patients with NT-proBNP above 862 pmol/l (i.e. in top quintile) showed significantly higher mortality rates, than patients with lower NT-proBNP; the adjusted odds ratio (and 95% confidence intervals) for all-cause death was in patients with NT-proBNP >862 pmol/l 3.26 (1.40-7.62). In conclusion, the asymptomatic elevation of NT-proBNP provides prognostic information also in stable coronary patients not yet manifesting any symptoms of heart failure.

High-sensitivity C-reactive protein and the hypertriglyceridemic waist in patients with type 2 diabetes and metabolic syndrome.

BACKGROUND: High-sensitivity C-reactive protein is an important biomarker of systemic inflammation. We studied the contribution to cardiovascular risk of increased high-sensitivity C-reactive protein in patients with type 2 diabetes with or without concomitant metabolic syndrome. MATERIAL/METHODS: The series included 381 patients (199 men, 182 women; median age, 66 years; age range, 50-80 years) with a mean duration of type 2 diabetes of 9+/-8 years. Standard physical examinations and laboratory investigations were administered to all patients. Modified National Cholesterol Education Program III criteria for defining the metabolic syndrome were used. High-sensitivity C-reactive protein was estimated by immunoturbidimetry and other laboratory tests using standard methods. RESULTS: High-sensitivity C-reactive protein correlated (Spearman's correlation) significantly positively with body mass index and waist size, fasting plasma triglyceride levels, apolipoprotein-B, gamma glutamyl transferase, homeostasis model assessment of insulin resistance, and fibrinogen, and negatively with high-density lipoprotein cholesterol. However, only waist, fibrinogen, apolipoprotein-B, plasma glucose, and gamma glutamyl transferase levels appeared to be associated with high-sensitivity C-reactive protein on multiple logistic regression model analyses. In those diabetic patients with concomitant metabolic syndrome, the hypertriglyceridemic waist appeared to be a major factor for an increased high-sensitivity C-reactive protein concentration. CONCLUSIONS: The hypertriglyceridemic waist contributes to the metabolic syndrome and most likely is an important factor increasing high-sensitivity C-reactive protein levels and consequently, relative coronary risk in patients with type 2 diabetes of any sex and age.

Hypothyroidism in coronary heart disease and its relation to selected risk factors.

INTRODUCTION: Hypothyroidism (HT) has been found a predictor of cardiovascular diseases. We aimed to ascertain the prevalence of HT in patients with manifest coronary heart disease (CHD), and to establish its association with conventional risk factors. METHODS: 410 patients, 6-24 months after hospitalization for acute coronary syndrome, and/or revascularization, were included into the cross-sectional study. RESULTS: The prevalence of thyroid dysfunction was found in males and females as follows: overt HT, ie, thyroid stimulating hormone (TSH) > 3.65 mIU/L and free thyroxine (fT4) < 9 pmol/L and/or L-thyroxine substitution, in 2.6% and 8.4%, respectively; subclinical HT (TSH > 3.65, fT4 9-23 and no substitution) in 4.3% and 15.0%, respectively. Higher prevalence of HT was found in females with hypercholesterolemia, and in males and females with concomitant positive thyroid peroxidase antibodies. Hypothyroid subjects had higher total homocysteine in both genders and von Willebrand factor in males only. Hypothyroid females had higher total and LDL cholesterol, and were more often treated for diabetes. CONCLUSIONS: HT was found highly prevalent in patient with clinical coronary heart disease, mainly in females, and was associated with several cardiovascular risk factors.

Short to long term mortality of patients hospitalised with heart failure in the Czech Republic--a report from the EuroHeart Failure Survey.

BACKGROUND AND AIM: The European Society of Cardiology initiated the EuroHeart Failure Survey to obtain more data about the quality of care in patients hospitalised with suspected heart failure (HF). The Czech Republic was 1 of the 24 European Society countries included in the survey. The aim of this report is to extend the original follow-up period of 12 weeks out to 4 years to assess mortality. METHODS: All admitted patients were screened according to the EuroHeart Survey Protocol, over a 6-week period in six hospitals in Pilsen, Prague and Brno in the year 2000. Annual mortality and cause of death were obtained from the Prague Institute for Health Statistical Information (UZIS Praha). RESULTS: A total of 2365 patients were screened and about 25% of all admitted patients fulfilled the criteria for HF. About 14% of patients died between admission and the 12-week follow-up, 36% of male and 42% of female patients died during the 4-year follow-up (2000-2003). Cardiovascular diseases were the main causes of death (92%). Deceased patients were significantly older, had lower haemoglobin and total plasma cholesterol level, and had renal insufficiency and higher levels of big endothelin and BNP than the survivors. Mortality risk was increased independently by positive history of previous myocardial infarction OR=2.39 (1.59-3.59), by age OR=1.03 (1.01-1.05) and by plasma creatinine level OR=1.04 (1.01-1.07). Treatment with diuretics and digoxin was associated with a higher risk of death; by contrast, a protective effect of beta-blockers and statins was found in these HF patients. CONCLUSION: Patients with HF were older and had a poor prognosis; approximately one third of the patients will die within 3 years.

Depressive disorders and the metabolic syndrome of insulin resistance.

Metabolic syndrome of insulin resistance and depression are both considered important cardiovascular risk factors. The aim of this study was to ascertain a possible association between these conditions in a population sample of 116 subjects (54 males, 62 females, aged 60 +/- 8 and 60 +/- 9 years, respectively). A standard questionnaire-the Hospital Anxiety Depression Scale-was used for the assessment of depressive disorder and clinical definition of insulin resistance, requiring the presence of three or more of the following factors: triglycerides > 1.7 mmol/L; and high-density lipoprotein cholesterol < 1.0 mmol/L; blood pressure >/= 130/85 mm Hg; waist circumference > 102 cm in males and > 88 cm in females; fasting glucose 6.1-7.8 mmol/L. Depressive disorders prevailed significantly more in women than in men (39% and 26%, respectively), and prevalence of depression in subjects with metabolic syndrome of insulin resistance (by definition) was about four times higher than in subjects without depression. Depressive subjects had also higher heart rate, waist circumference, lower high-density lipoprotein cholesterol, higher triglycerides, and higher body mass index. Higher sympathetic nervous activity in insulin-resistant subjects with depression was indicated.

Fibrate treatment and prevalence risk of mild hyperhomocysteinaemia in clinical coronary heart disease patients.

BACKGROUND: Several prospective studies reported that fibrates might increase blood total homocysteine (tHcy). In this study we aimed to establish whether the reported fibrate treatment was associated with an increased risk of mild hyperhomocysteinaemia in patients with clinical coronary heart disease, and to establish whether confounding variables may influence this effect. DESIGN: A retrospective, case-control analysis. METHODS: A total of 410 patients, 301 males and 109 females, mean age 59.2 were examined in a Czech sample from the EUROASPIRE II survey. In addition to examinations and measurements, defined by the protocol, we estimated serum total homocysteine (tHcy), folate, B12 vitamin and methylenetetrahydrofolate reductase (MTHFR) genotypes. RESULTS: We found significantly higher tHcy concentrations in patients with reported treatment with fibrate (16.6 +.- 0.66 micromol/l) compared with no lipid-lowering treatment (13.5 +/- 0.64 micromol/l, P<0.001) or to statin (12.4 +/- 0.39 micromol/l, P<0.001). Concentrations of tHcy > or =15 mmol/l (i.e. mild hyperhomocysteinaemia) as a dependent variable were positively associated with age (OR 1.18, P<0.0003), serum vitamin B12 (OR 0.87, P<0.003), serum creatinine (OR 1.35, P<0.0001 and treatment with fibrates (OR 1.30, P<0.0001), using multiple regression. Using unifactorial or multifactorial analyses, association between fibrate and tHcy is independent from conventional confounders such as age, gender, smoking, folate or B12 concentration, serum creatinine and MTHFR genotypes, however interference of low folate or B12 and fibrate treatment resulted in concentrations of tHcy more than 20 micromol/l. CONCLUSIONS: Fibrate treatment was associated with a significant increase in prevalence of the risk of mild hyperhomocysteinaemia in coronary patients, independently from conventional confounders.

Predictive value of classical risk factors and their control in coronary patients: a follow-up of the EUROASPIRE I cohort.

BACKGROUND: Both EUROASPIRE studies revealed the suboptimal management of coronary patients regarding lifestyle changes and prophylactic use of cardiovascular drugs. We report here on the mortality follow-up of the EUROASPIRE I cohort over a median period of 4.4 years. DESIGN AND METHODS: The EUROASPIRE I cohort consisted of a consecutive sample of patients aged < or =70 years from nine European countries, hospitalized because of coronary artery bypass graft, percutaneous transluminal coronary angioplasty, acute myocardial infarction or myocardial ischaemia. Baseline data, gathered in 1995-96 through standardized methods, were linked to cause-specific mortality as registered up to 1 April 2000 in 3343 patients. RESULTS: After adjustment for age, gender and diagnostic category according to Cox modelling, smoking, previous coronary heart disease and diabetes proved significant predictors of total, cardiovascular (CVD) and coronary heart disease (CHD) mortality. Obesity, low education, raised blood pressure, elevated total cholesterol and low HDL cholesterol, however, were not significantly associated with higher mortality rates. In multivariate analysis, smoking and diabetes emerged as the strongest predictors of CVD [risk ratios (RR) 2.2 and 2.5 respectively] and CHD mortality (RR 2.4 and 2.4 respectively). CONCLUSIONS: The results of the mortality follow-up of the EUROASPIRE I patients underline the importance of smoking and diabetes in the secondary prevention of CHD. Failure to find statistically significant associations between other classical risk factors, such as blood pressure and plasma lipid levels, and mortality may be related to the extensive use of antihypertensive and lipid-lowering drugs in this cohort.

Fenofibrate-induced hyperhomocysteinemia may be prevented by folate co-administration.

OBJECTIVES: Several prospective studies reported that fibrates might increase blood total homocysteine (tHcy) concentrations. Because of this adverse effect, elevated tHcy could potentially compromise the cardiovascular benefit resulting from lipid-lowering by fibrates. In our study we aimed to find out whether the folate co-administration would modify the fibrate-induced elevation of tHcy. METHODS: Twenty-four volunteers (m 17, f 7; mean age 54.9 years) with total cholesterol > or =6 mmol/L and triglycerides less than 5 mmol/L, with normal blood pressure, normal blood glucose and without any pharmacotherapy and/or clinical vascular or metabolic disease, were included in an open, randomised, prospective, crossover study. We measured lipids, tHcy, folate, vitamin B12 and renal function markers after diet, after a 6-month administration of 200 mg of fenofibrate (3 months in monotherapy followed by 3 months in combination with 10 mg of folate) and further on after an identical period of fluvastatin administration (3 months of 40 mg followed by 3 months of 80 mg). RESULTS: Fenofibrate in monotherapy, beside the expected lipid-lowering effect, increased tHcy from 10.0 to 14.2 microM/L ( p<0.001). Co-administration of folate decreased tHcy to 10.6 microM/L. In contrast, fluvastatin did not significantly influence the tHcy concentrations. CONCLUSION: Co-administration of folate to fenofibrate therapy has the potential to reverse the fibrate-induced elevation of tHcy.

The effects of folate supplementation on some coagulation parameters and oxidative status surrogates.

OBJECTIVE: To determine whether folate treatment, besides decreasing homocysteine (tHcy), improves coagulation status, oxidative stress and endothelial dysfunction and whether these depend on genetic polymorphism of the enzyme methylenetetrahydrofolate reductase (MTHFR). METHODS: Fifty-seven volunteers (males 30, females 27, mean age 61.2 years) with high coronary risk or manifest atherosclerotic disease and tHcy concentration of at least 20 micro mol/l participated in an open, prospective study - 1 month of placebo period, followed by 2 months of treatment with folate 10 mg daily. Concentrations of tHcy were measured using high-pressure liquid chromatography with fluorescence detection. Other variables were measured using commercial kits, and polymorphism of MTHFR was detected using a polymerase chain reaction. RESULTS: Folate treatment resulted in a significant decrease of tHcy and fibrinogen, while plasminogen and antithrombin III significantly increased. Glutathione peroxidase, glutathione and superoxide dismutase significantly increased after the folate treatment; moreover, malonyldialdehyde and von Willebrand factor decreased concomitantly. The individual MTHFR polymorphism did not influence the outcomes of folate treatment. CONCLUSION: Folate treatment resulted not only in tHcy decrease, but also in an improvement of hypercoagulation, oxidative stress and endothelial dysfunction. The sufficiently high dose of folate seems to be able to decrease plasma tHcy in all three individual MTHFR polymorphism groups, to almost the same post-treatment concentrations.