Tomasz Grycewicz

The effect of diabetic autonomic neuropathy on P-wave duration, dispersion and atrial fibrillation.

Introduction Atrial fibrillation (AF) is the most common sustained arrhythmia. Diabetic autonomic neuropathy (DAN) is a frequent complication of diabetes mellitus and has a negative impact on the cardiovascular system. There are no data about the occurrence of paroxysmal atrial fibrillation (PAF) in the population with DAN. Material and methods We analysed the data of 100 patients with PAF. The study population was divided into three groups: group I: 28 patients with diabetes mellitus (DM) and DAN, group II: 34 patients with DM without DAN, and group III: 38 patients without DM. P-wave duration (FPD) and dispersion (PWD) were measured during sinus rhythm and AF episodes were counted during 12 months of follow-up. Results Recurrence of PAF was higher in group I (47 episodes/year) compared to groups II and III (26 and 22 episodes/year) – p<0.01. The FPD was longer in group I (137.4 ±12.0 ms vs. 126 ±23.0 ms in II group and 129 ±18.3 ms in group III; p<0.001). The PWD was longer in patients with DAN (53 ±19 ms vs. 36 ±18 ms and 34 ± 20 ms, p<0.001). Conclusions The results showed that the presence of DAN caused a significant increase in P-wave duration and dispersion, which might be responsible for the recurrence of AF.

Endothelial function and left ventricular remodeling in diabetic and non-diabetic patients after acute coronary syndrome

Summary Background Endothelial dysfunction is an independent predictor of future cardiac events. Material/Methods We evaluated the relationship between flow-mediated dilation (FMD) in brachial artery and coronary risk factors in 93 patients (70 males, mean age: 62±8 years) with ACS treated with primary angioplasty (PCI). The patients were divided into 2 subgroups: 43 patients with diabetes mellitus type 2 (DM) and 50 non-diabetics (non-DM). Patients were examined on the 3rd day after ACS and after 6 months. FMD on the 3rd day were significantly lower in DM than in non-DM (5.8±2.2% vs. 8.8±4.9%, p=0.0007) and after 6 months (6.2±2.6% vs. 9.4±4.4%, p<0.0001). It was also observed that the improvement of FMD in both groups after a 6-month follow-up inversely correlated with the increase of left ventricular end-diastolic volume (LVEDV) (r=−0.41, p<0.001). Results There was an inverse relationship between FMD and age (r=−0.26, p<0.01), BMI (r=−0.26, p<0,005), total cholesterol (r=−0.56, p<0.001) and LDL cholesterol (r=−0.53, p<0.001). There was no relationship between triglycerides, hypertension and history of smoking. In the DM group, FMD negatively correlated with HbA1c (r=−0.68, p<0.001). Restenosis rate was significantly higher in the DM group (19% vs. 6%, p<0.001) but there was no relationship between FMD and restenosis. Conclusions Impaired FMD is more significant in diabetics than in non-diabetic patients with ACS. Lack of improvement of FMD after acute coronary syndrome can be a predictor of detrimental left ventricular remodeling in patients with ACS.

Platelet reactivity and mean platelet volume as risk markers of thrombogenesis in atrial fibrillation

Atrial fibrillation (AF) is associated with increased risk of thromboembolic complications. One of the markers of the increased risk of hypercoagulable state is platelet hyperreactivity. The aim of the study was to assess impact of arrhythmia on platelet reactivity. METHODS The study included 36 (mean age 48,3; range 21-60) male patients with lone atrial fibrillation, with exclusion of concomitant diseases known to trigger hypercoagulable state. The AF patients underwent cardioversion to restore sinus rhythm and were subsequently under observation for 1month. Echocardiography, ECG and blood collection was performed before cardioversion (T0) and 4weeks after successful cardioversion (T1). During the study period patients have been contacted and examined every week and 24h ECG monitoring was performed. Platelet reactivity was assessed based on changes of CD62 and CD42b expression on platelet surface after stimulation with thrombin. Also changes in MPV were assessed. RESULTS In all patients sinus rhythm was maintained at the end of the study period, however in 14 patients recurrences of AF were observed, confirmed by 24h ECG monitoring (atrial fibrillation recurrence group - AFR) and 22 patients maintained sinus rhythm throughout the whole study period (SR group). Mean fluorescence intensity (MFI) of CD62 on thrombin stimulated platelets decreased significantly 4weeks after electrical cardioversion as compared to T0 (48.04±22.42 vs 41.47±16.03; p<0.01). Also MFI of CD42b on thrombin stimulated platelets decreased significantly 4weeks after electrical cardioversion as compared to T0 (22.16±10.82 vs 12.06±5.99; p<0.0001). Platelets reactivity estimated by CD 62 expression in SR group decreased significantly after 4weeks observation (58.01±15.26 vs 46.57±13.44; p<0.001) opposite to AFR group 35.66±21.87 vs 34.54±16.4; p-ns). Moreover there were significant differences between basal reactivity during AF between SR and AFR groups (58.01±15.26 vs 35.66±21.87; p-0.01). MFI of CD42b on thrombin stimulated platelets decreased significantly both in AFR and SR groups (22.05±11.36 vs 13.8±6.03; p<0.001 and 21.87±14.18 vs 10.04±5.09; p<0005). MPV decreased significantly 4weeks after electrical cardioversion as compared to T0 (8.81±0.19 vs 8.42±0.14; p<0.0001). CONCLUSION The changes of platelet reactivity to thrombin observed after restoration of sinus rhythm in patients prove that arrhythmia intrinsically leads to increased reactivity of platelets.

Prognostic value of plasma N-terminal pro-B-type natriuretic peptide concentration in patients with normal and impaired left ventricular systolic function undergoing surgery for abdominal aortic aneurysm.

Introduction Implantation of an aortic-bifemoral prosthesis is characterised by a high (> 5%) rate of perioperative cardiovascular events. The main aim of the study is to demonstrate the usefulness of the determination of NT-proBNP concentration as a method of risk stratification of left ventricular dysfunction in patients subjected to surgery for aortic-bifemoral prosthesis implantation. Material and methods Forty consecutive patients were examined and subjected to aortic-bifemoral prosthesis implantation. The examined patients were divided into two groups: 1) with normal left ventricular systolic function and EF ≥ 58% (group I), 2) with left ventricular systolic dysfunction and EF < 58% (group II). Results In group I the median EF before surgery was 69.5% and the concentration of NT-proBNP 141.5 pg/ml. On day 7 after surgery respective values were EF 65.5%, NT-proBNP 498.55 pg/ml. In group II the median EF before surgery was 54%, and NT-proBNP concentration 303.9 pg/ml. Conclusions The concentration of plasma NT-proBNP before surgery well correlated with left ventricular ejection fraction. The values of NT-proBNP > 303.9 pg/ml strongly correlated with increased risk of left ventricular systolic dysfunction after surgery and they seem to have high prognostic value for the occurrence of cardiovascular events in this group of patients. The determination of NT-proBNP level on day 7 after surgery strongly correlated with the decrease of left ventricular ejection fraction in patients after the prosthesis implantation. It is a valuable diagnostic and prognostic factor of circulatory system efficiency before making a decision to discontinue hospitalization.

Effect of sinus rhythm restoration on platelet function in patients with lone atrial fibrillation.

Atrial fibrillation (AF) is associated with increased risk of thrombo- embolic complications. The aim of thestudywasto assessif arrhythmia, independent of other risk factors leads to increased platelet activation. The study involved 34 (mean age 50 +/� 9.03, range 21-59) male patients with lone persistent atrial fibrillation. The exclusion criteria were: age N60, coronary artery disease, left ventricular dysfunction (ejection fraction EF b 40%), congenital and acquired heart defects, artificial heart valve, diabetes, thyroid disease, inflammatory diseases, cancer, renal disease, and active smoking. The exclusion criteria precluded more than 95.4% of patients with AF hospitalized in our Department within the last 6 years. The AF patients underwent cardioversion to restore sinus rhythm and remained subsequently under observation for 1 month. Echocardi- ography, ECG and blood collection was performed before cardioversion (T0) and 4 weeks after successful cardioversion (T1). During the study period, patients were contacted and examined weekly along with 24-hour ECG monitoring. In all patients sinus rhythm was maintained at the end of the study period, however in 12 patients recurrence of AF was observed, confirmed by 24-hour ECG monitoring (atrial fibrillation recurrence group — AFR). In 10 patients the episodes of arrhythmia were asymp- tomatic, while only 2 patients complained of arrhythmia symptoms. In 22 patients no recurrence of AF in 24-hour ECG monitoring was observed (sinus rhythm group — SR). Parameters of resting platelets collected from peripheral blood activation was measured using flow cytometry. Platelet activation was assessed by expression of p-selectin (CD62) on platelets (CD61 positive cells). The platelet aggregate number was presented as a percentage of CD61+ blood elements bigger than platelets. The platelet derived microparticles (PDMPs) were assessed based on FSC histogram profile as CD61+ particles smaller than platelets. The leukocyte-platelet aggregates were detected based on coexpression of CD11b and CD62

Asymptomatic atrial fibrillation in patients with atrial fibrillation and implanted pacemaker

INTRODUCTION Atrial fibrillation is the most common chronic arrhythmia. Due to diagnostic difficulties, the exact prevalence of silent atrial fibrillation is not precisely defined. AIM The main aim of the present study was to assess the prevalence of asymptomatic atrial fibrillation and the relation between clinical status and presence of symptoms of atrial fibrillation. MATERIAL AND METHODS Fifty patients with implanted pacemaker with atrial fibrillation recording function and diagnosed paroxysmal atrial fibrillation were enrolled to the study in order to detect episodes of atrial fibrillation. Episodes lasting >1min were included into analysis. Patients were evaluated for presence of atrial fibrillation symptoms. RESULTS A total of 870 atrial fibrillation episodes were registered, the majority (93%) were asymptomatic. Episodes occurred more often during the day than during the night (p<0.001). Asymptomatic episodes occurred 13 times more frequently than symptomatic (p<0.001). Majority of episodes lasting up to 5min were asymptomatic, while episodes lasting over 24h were usually symptomatic (p<0.001). Furthermore, there were association between silent atrial fibrillation and lower HR (p=0.003), higher percentage of atrial (p=0.01) and ventricular pacing (p<0.001), male gender (p<0.001), presence of atrioventricular block (p<0.003), lower NYHA class (p<0.002), and calcium channel blockers (p=0.033) and diuretics intake (p<0.001). CONCLUSION In patients with bradycardia permanent pacemakers and paroxysmal atrial fibrillation, the proportion of asymptomatic episodes is very high. It was observed that shorter duration of the episodes, male gender, lower heart rate, presence of atrioventricular block, lower NYHA class, higher percentage of atrial and ventricular pacing, Ca2+ blockers, and diuretics intake predisposed to silent atrial fibrillation.