Influence of atrioventricular optimization on hemodynamic parameters and quality of life in patients with dual chamber pacemaker with ventricular lead in right ventricular outflow tract.

BACKGROUND: The aim of this study was to ascertain whether individual atrioventricular delay (AVD) optimization using impedance cardiography (ICG) offers beneficial hemodynamic effects as well as improved exercise tolerance and quality of life in patients with requiring constant right ventricular pacing. METHODS: There were 37 patients with advanced AV block included in the study. Several examinations were performed at the beginning. Next, the optimization of AVD by ICG was done. The next step of the study patients have been randomized into optimal AVD group (AVDopt) or factory setting group (AVDfab). After 3 months, the follow-up all data were collected again and crossover was performed. After another 3 months, during the final follow-up all these measures were repeated. RESULTS: In 87.5% patients, AVDopt were different than factory value. Cardiac output (CO), cardiac index (CI), and stroke volume (SV) were significantly (P < 0.001) higher in AVDopt group than in AVDfab group (CO: 6.0 ± 1.4 L/minute vs. 5.3 ± 1.2 L/minute; SV: 85.8 ± 25.7 mL vs.76.9 ± 22.5 mL; CI: 3.2 ± 0.7 L/minute/m(2) vs. 2.7 ± 0.6 L/minute/m(2) ). There was a statistical significant (P < 0.05) reduction of proBNP and NYHA class in patients with AVDopt compared to AVDfab (proBNP: 196.4 ± 144.7pg/mL vs. 269.4 ± 235.8 pg/mL; NYHA class: 1.7 ± 0.5 vs. 2.3 ± 0.6). Six-minute walking test was significantly (P < 0.05) higher in AVDopt group (409 ± 90 m) than in AVDfab group (362 ± 93 m). There were no statistically significant differences in echocardiographic parameters between AVDopt and AVDfab settings. CONCLUSION: Our study results suggest that AVD optimization in patients with DDD pacemaker with ICG improves hemodynamic when compared to the default factory settings. Furthermore, optimally programmed AVD reduces BNP and improves exercise tolerance and functional class.

[Atrial fibrillation in athletes]. / Migotanie przedsionków u sportowców.

Atrial fibrillation (AF) is the most common cardiac arrhythmia affecting up to 1-1.5% of the population. Regular physical activity reduces the risk of cardiovascular diseases, however several studies have shown paradoxically increased incidence of AF in people practicing sport, especially in elite athletes. The results of studies suggest a U-shape relationship between sport and risk of arrhythmia. Minor regular exertion protects from arrhythmia through reduction in AF risk factors, while intense physical activity increases the risk of arrhythmia. The etiopathogenesis of arrhythmia in athletes has not been fully elucidated yet, but it is definitely multifactorial. Arrhythmia's occurrence may be related to adaptative remodeling of a heart, autonomic nervous system alteration as well as may be associated with other factors like inflammation or dyselectrolitaemia. Atrial Fibrillation in athletes should always be considered as an abnormality which requires further investigation as in small percentage of cases arrhythmia may be the first manifestation of a structural heart disease or chanellopathy potentially leading to sudden cardiac death. Taking into account several problems related to pharmacotherapy, AF ablation has become the first line treatment in athletes.

[Value and circadian variations of QT dispersion in patients with diabetes mellitus and coronary artery disease]. / Wartosc dyspersji QT i jej zmiennosc dobowa u chorych na cukrzyce i chorobe wiencowa.

UNLABELLED: The frequency of onset of acute coronary syndromes and sudden cardiac death has been reported to have circadian variations, with a peak incidence in early morning hours. It has also been known that acute ischemia is a potent stimulus to increased dispersion of repolarization and development of malignant arrhythmias. QT dispersion (QTd) is used as an index of heterogenity of the ventricular repolarization and increases in patients with ischemic heart disease. The aim of the study was to investigate diurnal variations of QTd in patient with triple-vessel coronary artery disease (CAD) with and without diabetes mellitus type 2 (DM). MATERIAL AND METHODS: We investigated of 28 patients with stable triple-vessel CAD and 32 patients with similar advancement of changes in coronary circulation with co-existing DM. We excluded patients with prior myocardial infarction, taking oral medications which might alter QT interval and patients in which measurements of QT were difficult to perform or impossible. QTd measurements were taken semi-automatically every hour from 24 hours 12 leads Holter monitoring system (SUPRIMA 12). Measurements were verified independently by three observers. RESULTS: CAD patients without DM had QTd significantly greater in the morning hours (6 a.m. to 9 a.m.) in comparison with the other times (p < 0.01). The shortest QTd was measured during the night between 10 p.m. and 1 a.m. We did not observed circadian variations of QTd in patients with co-existent DM and values of QTd in this group was significantly greater then in CAD without DM group (p < 0.001). CONCLUSIONS: Our data proved that QTd in patients with CAD had a circadian variation with a peak value in the morning hours shortly after awakening. Patients with DM and CAD had not circadian variation of QTd but QTd values, during whole day and night, were significantly greater then patients without DM.

Reduced blood platelet sensitivity to aspirin in coronary artery disease: are dyslipidaemia and inflammatory states possible factors predisposing to sub-optimal platelet response to aspirin?

The study was designed to assess blood platelet sensitivity to acetylsalicylic acid and its associations with dyslipidaemia and inflammation in coronary artery disease patients. Platelet non-responsiveness to aspirin is associated with an increased risk of serious cardiovascular events. Several environmental and hereditary factors are reportedly involved in sub-optimal acetylsalicylic acid response. Forty-five coronary artery disease patients and 45 non-coronary artery disease controls received acetylsalicylic acid at a daily dose of 75-150 mg. Controls were examined twice: on the day of entering the study and 10 days later. Urinary 11-dehydrothromboxane B2 was assessed as the marker of platelet thromboxane generation. Aggregation was studied in platelet-rich plasma using turbidimetric aggregometry with collagen and arachidonic acid. Fifty to seventy percent of coronary artery disease patients showed an extent of collagen-induced aggregation above the upper quartile of the reference range compared with 8-15% in controls (P<0.003). For arachidonic acid-activated aggregation these proportions were 45-50% in coronary artery disease versus 7% in controls (P<0.007). In coronary artery disease patients, the acetylsalicylic acid-mediated platelet inhibition positively correlated with increased triglycerides (in arachidonic acid-stimulated platelets, r=0.30, P=0.0018), total cholesterol (r=0.33, P<0.0001 in coll and arachidonic acid-activated platelets) and elevated serum C-reactive protein (CRP) (r=0.27, P=0.0024). In coronary artery disease patients urine 11-dehydrothromboxane B2 concentrations were significantly increased compared to controls after 10 day acetylsalicylic acid intake (563; 313-728 pg/mg creatinine versus 321; 246-488 pg/mg creatinine, P=0.04). The incidence of suboptimal acetylsalicylic acid response incidence was more common in patients with coronary artery disease. Acetylsalicylic acid inhibition of blood platelet reactivity and thromboxane generation was less effective in these patients. Dyslipidaemia and chronic inflammatory states may promote suboptimal acetylsalicylic acid response in coronary artery disease patients.

[Right ventricle pacing site optimization guided by intracardiac echocardiography]. / Optymalizacja lokalizacji elektrody komorowej ukladu stymulujacego pod kontrola echokardiografii wewnatrzsercowej.

UNLABELLED: Right ventricle outflow tract (RVOT) is an alternative pacing site to right ventricle apex (RVA). Intracardiac echocardiography (ICE) is a new method for intracardiac structures visualization. THE AIM: is comparison of functional effects of DDD permanent ventricular pacing in patients with lead implanted in RVA or in RVOT with the use of traditional fluoroscopy or in RVOT guided by ICE. MATERIAL AND METHODS: 33 patients with AV block grade I/III no older than 75 y (mean age 65,9+/-0,3 years). Group 1: 10 patients with RVA lead implantation. Group II: 12 patients with leads implanted in RVOT with the use of ICE. Group IlI: 11 patients with lead positioned in RVOT with the use of fluoroscopy. High septum was established as an target pacing site for RVOT implantation. On 3 day and 3 months after implantation the following parameters were collected: VO2 max, 6-minute walking test distance, level of NT-proBNP. The comparison of relative changes was done, 3 month vs. 3 day for each parameter. RESULTS: Statistically significant greater decrease in NT-proBNP was found in Group II in comparison with both Group I and Ill (respectively p = 0.021 and p _ 0.034). Significantly greater increase in VO2 max was detected in patients Group II comparing to Group I (p = 0.047). Moreover it was found that ICE guided implantation is most effective in precise lead positioning. CONCLUSION: ICE guided lead localization on high interventricular septum seems to have better functional characteristics than other right ventricle pacing sites.

The relationship between sex hormones and lipid profile in men with coronary artery disease.

BACKGROUND: Men are more prone to develop coronary artery disease (CAD) than women and the mechanism of this different susceptibility is not well elucidated. The aim of this study was to evaluate the relationship between serum levels of several sex hormones and serum levels of lipoproteins, as well as the association between sex hormones and clinical covariates in men with stable coronary artery disease. METHODS: Study population consisted of 111 men (mean age 55 years) with stable coronary artery disease. In all patients levels of testosterone, dehydroepiandrosterone sulfate (DHEA-S), estradiol, sex hormone binding globuline (SHBG), luteinizing hormone (LH) and follicle stimulating hormone (FSH) were measured and free testosterone index (FTI) was calculated knowing SHBG. Standard lipid analysis included total cholesterol, HDL-cholesterol, LDL-cholesterol, and triglycerides. The extent of coronary artery disease was defined using semiquantitative coronary angiography score. RESULTS: Significant positive correlations were found between estradiol levels and levels of total cholesterol (r = 0.31; p = 0.005), LDL-cholesterol (r = 0.32; p=0.004), total cholesterol/HDL ratio (r = 0.26; p = 0.020), and triglycerides (r = 0.24; p = 0.030), whereas no significant association was found between levels of these lipids and testosterone or DHEA levels. HDL cholesterol showed a significant association with levels of FSH (r = 0.23; p = 0.03) and LH (r = 0.25; p = 0.02). CONCLUSIONS: Our results indicate a possible role of estradiol in promoting the development of atherogenic lipid milieu in men with CAD. Simultaneously, the observed association between increased FSH and LH levels with increased levels of HDL cholesterol might suggest a protective effect of these hormones.

Whether noninvasive optimization of AV and VV delays improves the response to cardiac resynchronization therapy.

BACKGROUND: Device optimization is not routinely performed in patients who underwent cardiac resynchronization therapy (CRT) device implantation. Noninvasive optimization of CRT devices by measurement of cardiac output (CO) can be used as a simple method to assess ventricular systolic performance. The aim of this study was to assess whether optimization of atrioventricular (AV) and interventricular (VV) delay can improve hemodynamic response to CRT and whether this optimization should be performed for each patient individually. METHODS: Twenty patients with advanced heart failure New York Heart Association (NYHA) class III/IV, left ventricular ejection fraction ≤ 35% and left bundle branch block (QRS ≥ 120 ms) in sinus rhythm were evaluated from 24 h to 48 h after implantation of a CRT device by means of impedance cardiography (ICG). CO was first measured at each patient's intrinsic rhythm. Patients then underwent adjustments of AV and VV delay from 80 ms to 140 ms and from -60 ms to +60 ms, respectively in 20 ms increment steps and CO at each setting was measured by ICG. Both AV and VV delays were programmed according to the greatest improvement in CO compared to intrinsic rhythm. RESULTS: There was a statistically signifi cant increase in CO measured at the intrinsic rhythm compared to different AV delay by mean of 21% (3.8 ± 1.0 vs. 4.6 ± 0.1 L/min, p < 0.05). Optimal AV/VV delays with left ventricle-preexcitation or simultaneous biventricular pacing caused additional increased CO from intrinsic rhythm by mean of 32.6% (3.8 ± 1.0 vs. 5.04 ± ± 1.0 L/min, p < 0.05). Optimal AV/VV setting delays also resulted in improved hemodynamic responses compared to VV factory setting delay. CONCLUSIONS: Both AV and VV delay optimization should be performed in clinical practice. Optimal AV delay improved outcome. However, combination of optimized AV/VV delays provided the best hemodynamic response. Optimized AV/VV delays with left ventricle-preexcitation or simultaneous biventricular pacing increased hemodynamic output compared to intrinsic rhythm and VV factory setting delay.

Risk factors for atrial fibrillation: Not always severe heart disease, not always so 'lonely'.

The precise mechanisms that cause atrial fibrillation (AF) are not completely understood. Clinicians should ask themselves whether AF is truly 'lone' or is the effect of an underlying, 'masked' disorder. Atrial fibrillation shares strong epidemiological associations with other cardiovascular diseases such as heart failure, coronary artery disease, valvular heart disease, diabetes mellitus and hypertension. In this review, we discuss the 'new risk factors' and the mechanisms by which they lead to AF. Based on the most recent studies, we present the current knowledge about the relationship between AF occurrence and the following disorders: metabolic syndrome and its components, sleep apnea and inflammation. Moreover, some aspects of the influence of lifestyle (alcohol consumption and physical activity) on AF events are described.

Usefulness of prolonged P-wave duration on signal averaged ECG in predicting atrial fibrillation in acute myocardial infarction patients.

BACKGROUND: Atrial fibrillation (AF) is a frequent complication of acute myocardial infarction (AMI), with a reported incidence of 7-18%. The incidence of congestive heart failure, in-hospital mortality, and long-term mortality is higher in AMI patients with AF than in those without. P-wave duration (PWD) on Signal-Averaged ECG is a non-invasive marker of intra-atrial conduction disturbances, which are believed to be the main electrophysiological cause of AF. MATERIAL/METHODS: In the present study we investigated whether PWD can predict development of AF in 130 AMI patients (100 men and 30 women, aged 56.9+/-12). PWD was recorded, along with clinical and hemodynamic characteristics. RESULTS: During the observation period (up to 21 days) 22 patients (16.9%) developed AF. In univariate analysis the variables associated with development of AF were age>65, Killip class III-IV, and PWD>125 ms. Stepwise logistic regression analysis showed that age>65 and PWD>125 ms were independently associated with AF. CONCLUSIONS: PWD measured in a very early period of AMI is a useful tool in predicting AF.

P wave dispersion and P wave duration on SAECG in predicting atrial fibrillation in patients with acute myocardial infarction.

BACKGROUND: Atrial fibrillation (AF) is a frequent complication of acute myocardial infarction (AMI), with reported incidence of 7% to 18%. The incidence of congestive heart failure, in-hospital mortality, and long-term mortality is higher in AMI patients with AF than in AMI patients without AF. P wave duration on signal-averaged ECG (PWD) and P wave dispersion on standard ECG (Pd) are noninvasive markers of intra-atrial conduction disturbances, which are believed to be the main electrophysiological cause of AF. METHODS: In the present study we investigated prospectively whether P wave duration on SAECG and P wave dispersion on standard ECG can predict development of AF in a group of patients with AMI. One hundred and thirty patients (100 men and 30 women, aged 56.9 +/- 12) with AMI were investigated. PWD, Pd, their clinical and hemodynamic characteristics were collected. RESULTS: During the observation up to 14 days, 22 patients (16.9%) developed AF. Univariate analysis variables associated with development of AF: age > 65 years, Killip class III-IV, PWD > 125 ms, and Pd > 25 ms. Stepwise logistic regression analysis showed that age > 65 years, PWD > 125 ms, and Pd > 25 ms were independently associated with AF. CONCLUSIONS: PWD and Pd both measured in a very early period of AMI are useful in predicting AF.

Sex steroids and heart rate variability in patients after myocardial infarction.

BACKGROUND: Although the relationship between sex steroid levels and coronary artery disease (CAD) has been the subject of many studies there are still controversies concerning the role of sex steroids in CAD. In patients with CAD, especially after a myocardial infarction, there is evidence for autonomic nervous system dysfunction. However, there is no data detailing the relationship between sex steroids and cicardian autonomic activity in patients with CAD. The aim of the study was to evaluate the association between sex steroids and heart rate variability (HRV) parameters in postinfarction patients. METHODS: In 88 postinfarction men (aged 36-73, average 53 years), 24-hour Holter monitoring was performed to assess HRV parameters: SDNN, SDNNI, SDANN, rMSSD, pNN50, and levels of the following hormones were measured: testosterone, estradiol, free testosterone index, and estradiol/testosterone ratio. Univariate and multivariate regression analyses were used to investigate the relationship between HRV parameters and levels of tested hormones. RESULTS: Increased testosterone levels were associated with increased SDNN (r = 0.38, P = 0.03), increased rMSSD (r = 0.51, P = 0.002), and increased pNN50 (r = 0.45, P = 0.007). These associations remained significance after adjustment for age, ejection fraction, and other relevant clinical covariates. There was no significant association between estradiol and HRV parameters. CONCLUSION: In men with a history of myocardial infarction, higher levels of testosterone are associated with higher HRV measures of parasympathetic activity. These findings suggest that testosterone beneficially influences autonomic regulation of the heart.

[Sex steroids and heart rate variability in men with coronary artery disease after myocardial infarction]. / Steroidy plciowe a zmiennosc rytmu serca u mezczyzn z choroba wiencowa po zawale serca.

The role of sex steroids in coronary artery disease (CAD) has been studied for years. In patients after myocardial infarction autonomic nervous system dysfunction has been described. Heart rate variability (HRV) analysis is one of the method of autonomic nervous system evaluation. The aim of the study was to evaluate correlations between sex steroids and HRV in 88 men (aged 36-73, av. 53 yrs), with the history of MI, with angiographically documented CAD. In all the patients 24-hour Holter monitoring was performed to assess HRV time domain parameters: SDNN, SDNNI, SDANN, rMSSD, pNN50. Levels of testosterone and estradiol were measured in two subsequent blood samples, taken with 30 min interval. Free testosterone index as well as estradiol/testosterone ratio were assessed. For statistics r-Spearman test was used. Positive correlations were found between testosterone and SDNN (r = 0.38, p = 0.03), testosterone and rMSSD (r = 0.51, p = 0.002) and between testosterone and pNN50 (r = 0.45, p = 0.007). Since rMSSD and pNN50 are parameters describing parasympathetic activity, our results suggest that in CAD men with the history of myocardial infarction, testosterone may influences the function of autonomic nervous system promoting parasympathetic dominance. It can be favorable for the circulatory system function.

The impact of very late revascularization of occluded infarct-related artery on cardiac mortality and the incidence of sudden death in survivors of acute myocardial infarction - long-term observation.

BACKGROUND: In survivors of acute myocardial infarction (AMI), an occluded infarct-related artery (IRA) is an important predictor of cardiac death (CD) and sudden death (SD). Early reperfusion of the IRA was associated with improved survival rate. The purpose of the present study was to assess if late IRA revascularization, performed 10-30 days after AMI, also has a beneficial effect on the incidence of CD and SD during an 18-month follow-up. MATERIAL/METHODS: The study population consisted of 93 post-MI patients with occluded IRA on coronary angiography. The patients were divided into 2 groups according to IRA status at discharge -- revascularized (47 patients) or occluded (46 patients) -- and followed. Before revascularization, the two groups of patients did not differ in the prevalence of clinical and angiographic variables, or in the incidence of risk factors for SD. In patients who underwent angioplasty or bypass graft surgery of closed IRA, the markers of electrical instability demonstrated no significant improvement after revascularization. RESULTS: During the 18-month follow-up a significantly lower incidence of CD (0% vs 15%, p<0.01) and SD (0% vs 11%, p<0.03) was observed in the group of patients with revascularized IRA than in the group of patients with occluded IRA. CONCLUSIONS: In survivors of AMI, late reperfusion of occluded IRA is associated with reduced 18-month cardiac mortality. The beneficial effect of this procedure on the incidence of sudden death, not associated with improvement in myocardial electrical stability, suggests that ischemia can be considered an important factor modulating the arrhythmogenic substrate.