The importance of sleep apnea index determination using 24 h ECG analysis in patients with heart rhythm disorders.

BACKGROUND/AIM: A possible cause of malignant heart rhythm disorders is the syndrome of sleep apnea (periodic cessation of breathing during sleep longer than 10 seconds). Recent 24 h ECG software systems have the option of determination ECG apnea index (AI) based on the change in voltage of QRS complexes. The aim of the study was to determine the significance of AI evaluation in routine 24-hour Holter ECG on a group of 12 patients. METHODS: We presented a total of 12 consecutive patients with previously documented arrhythmias and the history of breathing disorders during night. They were analyzed by 24 h ECG (Medilog AR 12 plus Darwin), that is able to determine AI. RESULTS: We presented a case series of 12 patients, 8 men and 4 women, mean age 58.75 years and the average AI 5.78. In the whole group there was a trend of increasing prevalence of complex rhythm disorders with increasing of AI and increased frequency of arrhythmias in the night phase vs. day phase. CONCLUSION: Determination of AI using routine long term (24 h) ECG analysis is important because sleep apnea can be successfully treated as an etiological or contributing factor of arrhythmias.

Correlation of N-terminal pro-B-type natriuretic peptide with clinical parameters in patients with hypertension.

BACKGROUND/AIM: Identification of patients with arterial hypertension and a possible onset of heart failure by determining the concentration of N-terminal pro-B-type natriuretic peptide (NT-proBNP) enables timely intensification of treatment and allows clinicians to prescribe and implement optimal and appropriate care. The aim of this study was to evaluate NT-proBNP in patients with longstanding hypertension and in patients with signs of hypertensive cardiomyopathy. METHODS: The study involved 3 groups, with 50 subjects each: "healthy" persons (control group), patients with hypertension and normal left ventricular systolic function (group 1) and patients with longstanding hypertension and signs of hypertensive cardiomyopathy with impaired left ventricular systolic function (group 2). We measured levels of NT-proBNP, C-reactive protein and creatinine according to the manufacturer's instructions. All the patients were clinically examined including physical examination of the heart with blood pressure, pulse rate, electrocardiogram (ECG) and echocardiogram. RESULTS: Our results showed that the determined parameters generally differed significantly (Student's t-test) among the groups. The mean (+/- SD) values of NT-proBNP in the control group, group 1 and group 2 were: 2.794 (+/- 1.515) pmol/L, 9.575 (+/- 5.449) pmol/L and 204.60 (84,93) pmol/L, respectively. NT-proBNP correlated significantly with the determined parameters both in the group 1 and the group 2. In the group 1, the highest correlation was obtained with C-reactive protein (r = 0.8424). In the group 2, the highest correlation was obtained with ejection fraction (r = -0.9111). NT-proBNP showed progressive increase in proportion to the New York Heart Association (NYHA) classification. The patients in the- group 2 who belonged to the II and III NYHA class had significantly higher levels of NT-proBNP than those in the NYHA class I (ANOVA test, p = 0.001). CONCLUSION: The obtained results suggest that NT-proBNP is a useful biomarker in the treatment of patients with longstanding hypertension who are at risk for heart failure.

Influence of peritoneal dialysis solution biocompatibility on long-term survival of patients on continuous ambulatory peritoneal dialysis and the technique itself.

BACKGROUND/AIM: Morbidity and mortality of continous ambulatory peritoneal dialysis (CAPD) patients is still very high. The aim of the study was to evaluate the effects of peritoneal dialysis (PD) solutions (standard vs biocompatible) on long-term patients' and the techique survival. METHODS: A total of 42 stable patients on CAPD participated in this cross-sectional study. They were prospectively followed-up during the twelve years. Patients with severe anemia (Hb < 10 g/L) and malignant disease ware excluded. Twenty one (50%/0) patients were treated with the standard PD solutions (CAPDP-1) while the other 21 (500/0) were treated with biocompatible PD solutions [(lower level of glucose degradation products, lower concentration of Ca(2+) and neutral pH (CAPDP-2)]. All patients were analyzed for a presence of vascular calcification, nutrition status, and parameters of inflammation after 2.5 +/- 0.6 years of starting CAPD, and these variables considered in the analysis as risk factors. RESULTS: The patients from the group CAPDP-2 compared to those from the group CAPDP-1 had lower level of high-sensitivity C-reactive protein (hs-CRP) (p = 0.003), and better nutritional status as confirmed by the mid-arm circumference (p = 0.015), and mid-arm muscle circumference (p = 0.002) and subjective global assessment (p = 0.000). Also, they had lower vascular calcifications as confirmed by intima media thickness (IMT) (p = 0.003), degree of carotid narrowing (p = 0.001) and calcified plaques of common carotid arteries (CCA) (p = 0.008). Kaplan-Meier analysis confirmed better survival of patients from the group CAPDP-2 than those from the group CAPDP-1 (1-, 5-, and 10-year patients survival rate was: 100%, 61.9% and 14.3% for the group CAPDP-1, and 100%, 85.7%, and 52.4% for the group CAPDP-2, respectively; p = 0.0345). The 1-, 5-, and 10-year technique survival rate was: 100%, 71.4%, and 38.1% for the group CAPDP-1, and 100%, 85.7%, and 76.2% for the group CAPDP-2, respectively; (p = 0.0719). Duration of dialysis, serum triglyceride and cardiovascular score (quantitative scoring system consisting of: ejection fraction (EF) of left ventricle < 50%; IMT > 1 mm; carotid narrowing degree > 50%, presence of carotid plaques in both common carotide, ischaemic heart disease, cerebrovascular event and peripheral vascular disease with or without amputation) were independent predictors of overall patient survival. Duration of dialysis was only independent predictor of overall technique survival. CONCLUSION: Although patients treated with biocompatible solutions showed significantly better survival, the role of biocompatibility of CAPD solutions in patients and technique survival have to be confirmed. Namely, multivariate analysis confirmed that duration of dialysis, serum triglyceride and cardiovascular score significantly predicted overall CAPD patients survival, while only duration of dialysis was found to be independent predictor of overall techique survival.

[Correlation between dialysis solution type and cardiovascular morbidity rate in patients undergoing continuous ambulatory peritoneal dialysis].

BACKGROUND/AIM: Peritoneal dialysis (PD) patients have an increased risk for cardiovascular diseases. The aim of the study was to evaluate the cardiovascular changes in patients undergoing chronic PD and the eventual existing differences depending on biocompatibility of dialysis solutions. METHODS: After 3 +/- 2 years of starting PD, 21 PD patients on the treatment with bioincompatible dialysis solutions (conventional glucose- based solutions: PDP-1), average age 47.43 +/- 12.87 years, and 21 PD patients on the treatment with biocompatible dialysis solutions (neutral solutions with lower level of glucose degradation products, lower concentration of Ca2+ and neutral pH: PDP-2), average age 68.62 +/- 13.98 years, participated in the longitudinal study. The average number of episodes of peritonitis was similar in both groups: 1 episode per 36 months of the treatment. The control group included 21 patients with preterminal phase of chronic renal failure (Glomerular Filtration Rate: 22.19 +/- 10.73 ml/min), average age 65.29 +/- 13.74 years. All the patients underwent transthoracal echocardiography (in order to detect: eject fraction (EF), left ventricular hypertrophy (LVH), and valvular calcification (VC) and B-mode ultrasonography of common carotid artery (CCA): IMT, lumen narrowing, and plaque detection. RESULTS: The values of EF were: in PDP-1 group 62.05 +/- 5.65%, in PDP-2 group 53.43 +/- 7.47%, and in the control group 56.71 +/- 8.12% (Bonferroni test, p = 0.001). The recorded LVH was: in PDP-1 group in 47.6% of the patients; in PDP-2 group in 61.9% of the patients; and in control the group in 52.4% (chi2 test; p = 0.639). The detected VC was: in PDP-1 in 52.4% of the patients, in PDP-2 group in 42.9% of the patients, and in the control group in 23.8% of the patients (chi2 test; p = 0.776). The IMT was: in PDP-1 group 1.26 +/- 0.54 mm, in PDP-2 group 1.23 +/- 0.32, and in the control group 1.25 +/- 0.27 mm (Bonferroni test; p = 0.981). An average lumen narrowing was: in PDP-1 group 13.78 +/- 18.26%, in PDP-2 group 18.57 +/- 22.98%, and in the control group 25.00 +/- 28.02% (Kruskal Wallis test; p = 0.413). Calcified plaques of CCA were detected in PDP-1 group in 61.9% of the patients, in PDP-2 group in 85.7%, of the patients and p = 0.159). CONCLUSION: Generally, PD had a significant influence on cardiovascular morbidity in the treated patients, especially on the left ventricular function and peripheral atherosclerosis. The age of the patients had more influence on acceleration of atherosclerosis than the length of dialysis or biocompatibility of dialysis solutions.

Amifostine protection against doxorubicin cardiotoxicity in rats.

Aminothiol amifostine (AMI) protects against toxic effects of both ionizing radiation and numerous anticancer drugs. The aim of this study was to investigate the potential protective effects of AMI against doxorubicin (DOX)-induced cardiotoxicity in rats. Male Wistar rats were treated with AMI (75 mg/kg i.p.) and/or DOX (1.25 mg/kg i.p.), 4 times per week, for 4 weeks. Mortality, general condition and body weight of the animals were observed during the whole treatment, and for a further 4 weeks, until the end of experiment. Evaluation of cardioprotective efficacy of AMI was performed by analyzing the electrocardiographic parameters and response to the pro-arrhythmic agent aconitine, as well as activity registration of the in situ rat heart preparations. Necropsy was also performed at the end of the experiment, and heart excision, weight and macroscopic examination were done before histological evaluation. Doxorubicin caused rat heart disturbances manifested by prominent electrocardiographic changes (Salpha-T prolongation and T-wave flattening), significantly enhanced response to aconitine, decrease of the heart rate and contractility, as well as histopathologically verified myocardial lesions. The heart changes were accompanied by 40% mortality rate, significant decline in body mass and severe effusion intensity score in 66.6% of the animals. Application of AMI before each dose of DOX significantly reduced or completely prevented its toxic effects. Therefore, since AMI had very good protective effects against a high dose of DOX given as a multiple, low, unitary dose regimen, not only on the heart but on the whole rat as well, it could be recommended for further investigation in this potentially new indication for clinical application.

[Acute poisoning with cardiovascular agents]. / Akutna trovanja kardiovaskularnim lekovima.

In order to determine the frequency, severity of poisoning, and the efficacy of the applied therapeutic measures, retrospective study of 391 patients treated for acute drug poisoning was performed during one-year period at the Clinic for Emergency and Clinical Toxicology and Pharmacology. In 49 (12.5%) patients cardiovascular agents were the cause of poisoning, most frequently beta-blockers and calcium antagonists (77.5%). Poisoning with antihypertensive agents was registered in 12.2% of patients, antiarrhythmics in 8.2%, and cardiotonics in 2.1%. Beta-blockers and calcium antagonists caused severe poisoning in over 40% of cases. Predominant clinical manifestations were registered on cardiovascular system, while central nervous system effects occurred secondary to cardiotoxicity. Symptomatic and supportive measures were performed most frequently, while specific agents, glucagon, calcium salts, and others, were used less often.