Kudret Aytemir

P Wave Dispersion on 12-Lead Electrocardiography in Patients with Paroxysmal Atrial Fibrillation

The prolongation of intraatrial and interatrial conduction time and the inhomogeneous propagation of sinus impulses have been shown in patients with atrial fibrillation. Recently P wave dispersion (PWD), which is believed to reflect inhomogeneous atrial conduction, has been proposed as being useful for the prediction of paroxysmal atrial fibrillation (PAF). Ninety consecutive patients (46 men, 44 women; aged 55 ± 13 years) with a history of idiopathic PAF and 70 healthy subjects (42 men, 28 women; mean age, 53 ± 14 years) were studied. The P wave duration was calculated in all 12 leads of the surface ECC. The difference between the maximum and minimum P wave duration was calculated and this difference was defined as P wave dispersion (PWD = Pmax ‐ Pmin). All patients and controls were also evaluated by echocardiography to measure the left atrial diameter and left ventricular ejection fraction (LVEF). There was no difference between patients and controls in gender (P = 0.26), age (P = 0.12), LVEF (66 ± 4% vs 67 ± 5%, P = 0.8) and left atrial diameter (36 ± 4 mm vs 34 ± 6 mm, P = 0.13). P maximum duration was found to be significantly higher in patients with a history of PAF (116 ± 17 ms) than controls (101 ±11 ms. P < 0.001). P wave dispersion was also significantly higher in patients than in controls (44 ± 15 ms vs 27 ± 10 ms, P < 0.001). There was a weak correlation between age and P wave dispersion (r = 0.27, P < 0.001). A P maximum value of 106 ms separated patients with PAF from control subjects with a sensitivity of 83%, a specificity of 72%, and a positive predictive accuracy of 79%. A P wave dispersion value of 36 ms separated patients from control subjects with a sensitivity of 77%, a specificity of 82%, and a positive predictive accuracy of 85%. In conclusion, P maximum duration and P wave dispersion calculated on a standard surface ECG are simple ECG markers that could be used to identify the patients with idiopathic paroxysmal atrial fibrillation.

Assessment of Endothelial Function in Alzheimer's Disease: Is Alzheimer's Disease a Vascular Disease?

OBJECTIVES: To compare endothelial function of people with Alzheimers disease (AD) with that of people without.

Methylene tetrahydrofolate reductase genotype and the risk and extent of coronary artery disease in a population with low plasma folate

OBJECTIVE To determine the effects of the thermolabile methylene tetrahydrofolate reductase (MTHFR) mutation on the presence and extent of coronary atherosclerosis in a population with low plasma folate. METHODS 242 consecutive patients undergoing coronary angiography were prospectively evaluated for conventional risk factors, plasma homocysteine, vitamin B-12, and folate, and MTHFR genotype. The severity of coronary atherosclerosis was determined by the Leaman score. RESULTS Mean (SD) plasma homocysteine was 15.6 (10) μmol/l in controls and 18.5 (11) μmol/l in patients with coronary artery disease (p > 0.05). Plasma homocysteine concentrations above 15 μmol/l were a risk factor for coronary artery disease (p = 0.03, risk ratio 2.1, 95% confidence interval (CI) 1.07 to 4.4). Homocysteine remained an independent risk factor on multivariate analysis when conventional risk factors were taken into account (p = 0.04). Homocysteine concentrations above 15 μmol/l were correlated with the extent of atherosclerosis (p = 0.04, risk ratio 3.2, 95% CI 1.3 to 8.2). Homocysteine had no effect on other lipid variables (p > 0.05). Plasma folate was 15.8 (7.2) nmol/l in controls and 11.5 (2.9) nmol/l in patients with coronary artery disease. Plasma folate concentrations below 12.9 nmol/l (5.7 ng/ml) conferred a risk for coronary artery disease (p = 0.03, risk ratio 2.42, 95% CI 1.05 to 5.59). When the MTHFR genotype was determined, the TT genotype was present in 7.4% of patients and 5.2% of controls (p > 0.05). The prevalence of alleles was within the Hardy–Weinberg equilibrium (TT 7, CT 40, CC 53, χ2 = 2.3, p = 0.3). The highest homocysteine concentrations were found in patients with the TT genotype and folate below the median of the population (p = 0.01). The extent of coronary atherosclerosis judged by the Leaman score was significantly higher in patients with the TT genotype (p = 0.03). CONCLUSIONS Plasma homocysteine over 15 μmol/l was a significant risk factor for the presence and extent of coronary artery disease. The mean plasma folate of the population was low and correlated negatively with homocysteine. Although TT genotype was not an independent predictor of coronary artery disease, it was an important predictor of the extent of coronary atherosclerosis and plasma homocysteine, especially in the presence of plasma folate values below the median of the population. These findings may have important implications for folate replacement in patients with the TT genotype.

P Wave Dispersion in Hypertensive Patients with Paroxysmal Atrial Fibrillation

It is important to assess the risk of developing paroxysmal atrial fibrillation (PAF) in hypertensive patients since hypertension is a common disorder predisposing to PAF. We sought to determine if patients with hypertension at risk of PAF can be identified while in sinus rhythm by measurements of P wave dispersion. Twelve‐lead surface electrocardiograms were recorded in 44 hypertensive patients with history of PAF (group I, mean age = 60) and in 50 hypertensive patients without history of AF (group II, mean age = 57). The maximum P wave duration, the minimum P wave duration, and P wave dispersion (Pd = Pmax ‐Pmin) were calculated from 12‐lead surface ECGs. Left atrial dimension (LAD) and left ventricular ejection fraction (LVEF) were measured by echocardiography. P wave dispersion was significantly greater in group I than group II (50 ± 12 vs 38 ± 8 ms, P = 0.001). P minimum (75 ± 13 vs 87 ± 11 ms, P = 0.001) and LVEF (0.63 ± 0.05 vs 0.67 ± 0.04, P = 0.03) were significantly lower in group I than group II. However P maximum and LAD were not significantly different in group I than group II (P > 0.05). In univariate analysis, P minimum, P wave dispersion, and LVEF were significant predictors of PAF, whereas only P wave dispersion remained a significant independent predictor of PAF in a multivariate analysis. Measurement of P wave dispersion in sinus rhythm may be a useful noninvasive clinical tool to identify patients with hypertension at risk of developing atrial electrical instability and atrial fibrillation.

Effects of inspiratory muscle training in patients with heart failure

AIM To investigate the effects of inspiratory muscle training (IMT) on functional capacity and balance, respiratory and peripheral muscle strength, pulmonary function, dyspnea, fatigue, depression, and quality of life in heart failure patients. METHODS A prospective, randomized controlled, double-blinded study. Thirty patients with heart failure (NYHA II-III, LVEF<40%) were included. Sixteen patients received IMT at 40% of maximal inspiratory pressure (MIP), and 14 patients received sham therapy (15% of MIP) for 6 weeks. Functional capacity and balance, respiratory muscle strength, quadriceps femoris muscle strength, pulmonary function, dyspnea, fatigue, quality of life, and depression were evaluated. RESULTS Functional capacity and balance, respiratory and peripheral muscle strength, dyspnea, depression were significantly improved in the treatment group compared with controls; quality of life and fatigue were similarly improved within groups (p < 0.05). Functional capacity (418.59 ± 123.32 to 478.56 ± 131.58 m, p < 0.001), respiratory (MIP = 62.00 ± 33.57 to 97.13 ± 32.63 cmH(2)O, p < 0.001) and quadriceps femoris muscle strength (240.91 ± 106.08 to 301.82 ± 111.86 N, p < 0.001), FEV(1)%, FVC% and PEF%, functional balance (52.73 ± 3.15 to 54.25 ± 2.34, p < 0.001), functional dyspnea (2.27 ± 0.88 to 1.07 ± 0.79, p < 0.001), depression (11.47 ± 7.50 to 3.20 ± 4.09, p < 0.001), quality of life, fatigue (42.73 ± 11.75 to 29.07 ± 13.96, p < 0.001) were significantly improved in the treatment group. Respiratory muscle strength (MIP = 78.64 ± 35.95 to 90.86 ± 30.23 cmH(2)O, p = 0.001), FVC%, depression (14.36 ± 9.04 to 9.50 ± 10.42, p = 0.011), quality of life and fatigue (42.86 ± 12.67 to 32.93 ± 15.87, p = 0.008) were significantly improved in the control group. CONCLUSION The IMT improves functional capacity and balance, respiratory and peripheral muscle strength; decreases depression and dyspnea perception in patients with heart failure. IMT should be included effectively in pulmonary rehabilitation programs.

Safety and efficacy outcomes in patients undergoing pulmonary vein isolation with second-generation cryoballoon

AIMS The second-generation cryoballoon (Arctic Front Advance™) (Arc-Adv-CB) has a redesigned injection system which distributes the refrigerant homogenously to the frontal balloon surface. The aim of this study was to compare the efficacy and safety of the Arc-Adv-CB and its predecessor (Arctic Front™) (Arc-CB) in patients who underwent pulmonary vein isolation (PVI) for atrial fibrillation (AF). METHODS AND RESULTS Three hundred and six patients (55.35 ± 10.60 years, 47.05% male) were included in the study. A total of 1205 pulmonary veins were attempted for PVI with either Arc-CB or Arc-Adv-CB. The follow-up durations were 30 (23-38) and 10 (8-13) months in Arc-CB and Arc-Adv-CB groups, respectively (P < 0.001). When the blanking period was considered, freedom from AF after a single ablation procedure was 68.53 and 90.83% in patients undergoing PVI with Arc-CB and Arc-Adv-CB, respectively. The most frequent complication was transient phrenic nerve palsy (PNP) which occurred in five(2.54%) and nine(8.26%) of patients undergoing PVI with Arc-CB and Arc-Adv-CB, respectively (P = 0.040). Left atrial (LA) diameter (hazard ratio, HR: 3.552, 95% CI: 2.034-6.201, P < 0.001), smoking history (HR:1.643, 95% CI: 1.011-2.671, P = 0.045), persistent AF (HR:1.725, 95% CI: 1.021-2.915, P = 0.041), duration of AF (HR:1.039, 95% CI: 1.000-1.080, P = 0.047), and early AF recurrence (HR:2.399, 95% CI: 1.443-3.989, P < 0.001) were associated with increased late AF recurrence. On the other hand, intraprocedural vagal reactions (HR: 0.550, 95% CI: 0.331-0.915, P = 0.021) and Arc-Adv-CB use (HR: 0.441, 95% CI: 0.225-0.866, P = 0.017) were associated with lower late AF recurrence. Left atrial diameter (HR: 3.072, 95% CI: 1.646-5.732, P < 0.001), early AF recurrence (HR: 1.906, 95% CI: 1.103-3.291, P = 0.021), and Arc-Adv-CB use (HR: 0.472, 95% CI: 0.239-0.931, P = 0.030) were independent predictors for late AF recurrence. CONCLUSION Our study has shown that Arc-Adv-CB use is associated with lower late AF recurrences at the cost of an increased risk for PNP.

Prediction of atrial fibrillation recurrence after cardioversion by P wave signal-averaged electrocardiography

The purpose of this report was to determine prospectively whether P wave signal-averaged electrocardiography (ECG) is useful for the prediction of recurrences of atrial fibrillation after cardioversion. The P wave signal-averaged ECG was recorded in 73 patients after successful cardioversion. Duration of the filtered P wave and the root mean square voltages for the last 20 ms of the P wave were calculated. In addition to signal-averaged ECG P wave analysis, all patients were evaluated by echocardiography. During 6 months follow-up period recurrence of atrial fibrillation was observed in 31 (42.5%) patients and in 42 (57.5%) patients sinus rhythm was maintained. There was no difference in gender, age, presence of organic heart disease, left atrial diameter, left ventricular ejection fraction, use of antiarrhythmic drug, and duration of atrial fibrillation (P>0.05). The filtered P-wave duration was longer and the root mean square voltages for the last 20 ms of the P wave was lower in patients with recurrence of atrial fibrillation than in patients who maintained sinus rhythm (138.3+/-12.5 ms vs. 112.4+/-11.8 ms, P = 0.001; 1.9+/-0.7 microV vs. 2.5+/-0.6 microV, P = 0.001). A filtered P-wave duration > or =128 ms associated with a root mean square voltage for the last 20 ms of the P wave < or =2.1 microV had a sensitivity of 70% and specificity of 76% for the detection of patients with recurrence of atrial fibrillation after successful cardioversion of atrial fibrillation. We found that the likelihood of recurrence of atrial fibrillation after cardioversion was increased 4.31-fold (95% confidence interval 2.08-9.83) if these parameters were used. These results suggest that P wave signal-averaged ECG could be useful to identify patients at risk for recurrence of atrial fibrillation after cardioversion.

P-wave duration and dispersion in patients with obstructive sleep apnea

AIM P-wave dispersion (Pd) has been reported to be associated with inhomogeneous and discontinuous propagation of sinus impulses. The purpose of this study was to investigate Pd in patients with obstructive sleep apnea (OSA) and to determine its relationship with severity of the disease. METHODS The study population included 67 patients referred to sleep laboratory. The Apnea-Hypopnea Index (AHI) was defined as the number of apneas and hypopneas per hour of sleep. Of the sixty-seven patients, 48 had AHI5 and were diagnosed as OSA. Nineteen of the patients had AHI<5 and were diagnosed as OSA (-) (Group 1), 32 of the patients had AHI between 5-30 (mild and moderate, group 2), 16 of the patients had AHI>30 (severe, group 3). The P-wave duration was calculated in all leads of the surface electrocardiogram. The difference between the maximum (Pmax) and minimum P (Pmin) wave duration was calculated and was defined as the P-wave dispersion (Pd). Echocardiographic examination was also performed. RESULTS Pmax was longer in group 3 compared to group 2 and group 1 (p=0.002, p<0.001 respectively). Pmax was longer in group 2 compared to group 1 (s<0.001). Pd was greater in group 3 compared to group 2 and group 1 (p<0.001 for both comparison). Pd was greater in group 2 compared to group 1 (p<0.001). Pmin did not differ between the groups. In patients with OSA, Pd was positively correlated with AHI (r=0.56, p<0.001), BMI (r=0.43, p=0.03), and mitral early diastolic to late diastolic velocity (E/A) ratio (r=0.37, p=0.01). Multiple linear regression analysis showed that only AHI was independently associated with Pd (beta=0.39, p=0.02). CONCLUSION Pd was found to be greater in patients with OSA than patients without OSA and to be associated with severity of the disease.

Advanced Age Is Associated with Endothelial Dysfunction in Healthy Elderly Subjects

Background: Aging is associated with an increased risk for atherosclerosis in which endothelial dysfunction is an early marker. Objective: The purpose of this study was to determine if endothelial function is altered with increasing age in healthy subjects. Method: The study population consisted of 30 elderly and 36 younger subjects free from major cardiovascular risk factors. Transthoracic echocardiography was performed for each subject to rule out structural heart disease. Endothelial function was evaluated by flow-mediated dilation (FMD) of the brachial artery via ultrasound. Results: Baseline characteristics of the elderly and the younger group were similar, except for age (mean age: 71.3 ± 5.8 vs. 26.5 ± 7.2). Transthoracic echocardiography was normal in all subjects. FMD of the elderly group was significantly lower than the younger group (7.9 ± 3.1 in the elderly, 10.8 ± 1.9 in the younger group, p < 0.001). A negative relationship was found between FMD and age (r = –0.528, p < 0.001). Conclusion: It can be concluded that endothelial function detected by FMD declines with increasing age in healthy human subjects. Advanced age is a predictor of impaired endothelial function.

Detection of Subclinical Cardiac Involvement in Systemic Sclerosis by Echocardiographic Strain Imaging

Background: Cardiac involvement is one of the major problems in systemic sclerosis (SSc). Subclinical cardiac involvement has a higher frequency than thought previously. In this study we investigated whether subclinical cardiac involvement can be detected by using echocardiographic strain imaging in SSc patients without pulmonary hypertension. Methods: Echocardiographic examinations were performed to 27 SSc patients and 26 healthy controls. Left ventricular strain parameters were obtained from apical views and average strain value was calculated from these measurements. Results: There were no significant differences between patients and controls regarding two‐dimensional (2D), conventional Doppler and tissue Doppler velocity measurements. Strain was reduced in 6 of 12 segments of the left ventricle (LV) and in 1 of 2 segments of the right ventricle (RV). Strain rate (SR) was reduced in 2 of 12 segments of the LV and 1 of 2 segments of the RV in SSc patients as compared to controls (P < 0.05 for all). These involvements did not match any particular coronary artery distribution. More important differences were detected by average strain and SR values of the LV between patients and controls (19.78 ± 3.00% vs 23.41 ± 2.73%, P < 0.001; 2.01 ± 0.41 vs 2.23 ± 0.27/sec, P = 0.026, respectively). Furthermore, carbon monoxide diffusion capacity (DLCO) in scleroderma patients significantly correlated with LV average strain (r = 0.59; P = 0.001). Conclusion: Evaluation of ventricular function by using echocardiographic strain imaging appears to be useful to detect subclinical cardiac involvement in SSc patients with normal standard echocardiographic and tissue Doppler velocity findings.