Ali Serdar Fak

Colchicine and Secondary Amyloidosis

Excerpt To the Editors:We are writing to support the observations in the letter by Zemer and Langevitz that secondary amyloidosis could be treated with colchicine (1). We have followed a 52-year-ol...

Effects of a single dose of oral estrogen on left ventricular diastolic function in hypertensive postmenopausal women with diastolic dysfunction

Abstract Objective: To evaluate the acute effects of a single dose of oral estrogen on left ventricular diastolic function in hypertensive postmenopausal women with diastolic dysfunction. Design: Prospective, double-blind, placebo-controlled, clinical study. Setting: Cardiology and postmenopausal outpatient clinics of a university hospital. Patient(s): Thirty postmenopausal women with hypertension (diastolic blood pressure of >90 mm Hg) and left ventricular diastolic dysfunction (mitral E/A ratio [the ratio of peak velocity of early mitral diastolic filling to late diastolic filling] of 100 ms) were included in the study. Thirty normotensive postmenopausal women with normal left ventricular diastolic function served as the control group. Intervention(s): Conjugated equine estrogen (0.625 mg) was given orally. Left ventricular diastolic function was assessed by Doppler echocardiography at baseline and 3 hours after the administration of estrogen. Main Outcome Measure(s): Left ventricular diastolic filling as assessed by Doppler echocardiography. Result(s): Estrogen had no effect on heart rate or blood pressure in either study group. The baseline E/A ratios were 0.72 ± 0.26 and 1.22 ± 0.30, and the isovolumic relaxation times were 122 ± 18 ms and 89 ± 14 ms in the hypertensive and normotensive groups, respectively. Estrogen had no significant effect on any of the Doppler parameters in the normotensive group. In the hypertensive group, there was a trend toward normalization of the E/A ratio (from 0.73 ± 0.11 to 0.84 ± 20) and a significant improvement in the isovolumic relaxation time (from 124 ± 20 ms to 105 ± 13 ms) in response to the administration of estrogen compared with placebo. Conclusion(s): A single dose of oral estrogen caused a significant improvement in left ventricular diastolic filling in hypertensive postmenopausal women with diastolic dysfunction.

P Wave Dispersion Increases during Hemodialysis Sessions

Background/Aims: Atrial fibrillation (AF) is common among hemodialysis (HD) patients and is associated with high mortality. P wave dispersion (PWD) is a noninvasive electrocardiographic marker of paroxysmal AF. Our aim was to evaluate the effect of HD session on PWD. Methods: Twenty-five patients (mean age 63 years, 10 males) with sinus rhythm and undergoing chronic HD treatment were included. Blood samples were drawn and 12-lead electrocardiograms were recorded immediately before HD session, at the 2nd hour during HD and at the end of the HD session. The difference between maximum and minimum P wave durations was calculated as PWD. Results: PWD significantly increased during HD sessions compared with predialysis values (41 ± 12 vs. 21 ± 10 ms, respectively, p < 0.001), then decreased to a value of 24 ± 7 ms at the completion of HD, which was not significantly different from the predialysis values. PWD during HD was significantly correlated with predialysis systolic and diastolic blood pressure (r = 0.42, p = 0.037, and r = 0.59, p = 0.002, respectively) and predialysis serum potassium level (r = 0.44, p = 0.031). Linear regression model revealed that predialysis diastolic blood pressure (p = 0.002), predialysis serum potassium level (p = 0.037) and the amount of ultrafiltration (p = 0.048) were the significant predictors of prolonged PWD during HD. Conclusion: PWD increases significantly during HD sessions. This may increase the risk of AF episodes during HD. High diastolic blood pressure and serum potassium level before HD and ultrafiltration amount may predict prolonged PWD during HD.

Polymorphisms of the angiotensin-converting enzyme and angiotensinogen gene in patients with atrial fibrillation

Activation of the renin–angiotensin system (RAS) is associated with atrial fibrillation (AF). The aim of this study was to investigate the relation between AF and polymorphisms in RAS. One hundred and fifty patients with AF, 100 patients with no documented episode of AF and 100 healthy subjects were consecutively recruited into the study. The angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism, and the M235T, A-20C, and G-6A polymorphisms of the angiotensinogen gene were genotyped. Patients with AF had significantly lower frequency of II genotype of ACE I/D and higher frequency of angiotensinogen M235T polymorphism T allele and TT genotype and G-6A polymorphism G allele and GG genotype compared with the controls. AF patients had significantly larger left atrium, higher left ventricular mass index (LVMI) and higher frequency of significant valvular pathology. ACE I/D polymorphism II genotype, angiotensinogen M235T polymorphism TT genotype and G allele and GG genotype of angiotensinogen G-6A polymorphism were still independently associated with AF when adjusted for left atrium, LVMI and presence of significant valvular pathology. Genetic predisposition might be underlying the prevalence of acquired AF. Patients with a specific genetic variation in the RAS genes may be more liable to develop AF.

The Effects of Amlodipine on Left Ventricular Mass and Diastolic Function in Concentric and Eccentric Left Ventricular Hypertrophy.

Background: The effects of the antihypertensive therapy with amlodipine (5-10 mg/day) on left ventricular mass and diastolic function were examined in 30 mild to moderate essential hypertensive patients who have left ventricular hypertrophy (LVH) and diastolic dysfunction. Methods and Results: Each patients left ventricular mass was measured, and left ventricular diastolic function was assessed by echocardiographic Doppler examination at entry, and at 3 and 6 months after the initiation of the treatment. Amlodipine reduced both blood pressure (from 164 ± 14/10 ± 6 mmHg to 134 ± 9/83 ± 4 mmHg) and left ventricular mass index (from 160 ± 30 g/m2 to 137 ± 26 g/m2) significantly at 3 months and both parameters maintained at these levels for 6 months. When the patients were classified according to the type of the LVH. a significant regression in left ventricular mass index was seen only in the patients who had concentric LVH with a relative wall thickness ≥ 0.44 (n = 16), but not in the eccentric LVH group (n = 14), although both groups were not significantly different from each other regarding the basal hemodynamic parameters. baseline left ventricular mass index and the decrease in blood pressure in response to amlodipine treatment. The mitral inflow E/A ratio did not show any significant change in either group. Conclusions: Across the three chronic heart disease risk strata, lovastatin appears to be significantly more potent than fluvastatin, on a per milligram basis, in lowering cholesterol levels.

QT Dispersion in Renal Transplant Recipients

An increased QT dispersion (QTd) is associated with a variety of cardiac diseases and predicts sudden death. Although chronic renal failure patients and patients on hemodialysis are shown to have an increased QTd, evidence of increased QTd in renal transplant patients is scarce. In this study, renal transplant patients were evaluated to find out if they had an increased QTd. Thirty-four renal transplant recipients aged 35 ± 8 years and 34 healthy control subjects aged 34 ± 8 years were included in the study. The mean time after transplantation was 51.8 ± 40.4 (range 5–154) months. The QT interval was measured by 12-lead electrocardiogram, and the QTd was defined as the difference between the maximum and minimum QT interval. Bazett’s formula was used to correct for the heart rate (QTc). Both QTd and QTc dispersion (QTcd) in renal transplant patients were compared with those of control subjects. All patients underwent transthoracic echocardiographic assessment and 24-hour ambulatory blood pressure monitoring. Renal transplant recipients had similar QTd (37 ± 15 vs. 39 ± 17 ms) and QTcd (50 ± 18 vs. 55 ± 20 ms) compared to control subjects. QTd and QTcd were similar in patients with and without left ventricular hypertrophy (QTd 37 ± 14 vs. 36 ± 17 ms and QTcd 50 ± 14 vs. 49 ± 21 ms, respectively). No association was found between QTd and left ventricular mass index or blood pressure measurements. The QTd was not found to be increased in renal transplant recipients as compared with that of healthy controls in this study. Normalization of the QTd after renal transplantation may be through the correction of several factors responsible for increased QTd in uremic patients.

A study to classify Non-Dipper/Dipper blood pressure pattern of type 2 diabetes mellitus patients without Holter device

The aim of this study was to design an expert system to predict the Non-Dipping or Dipping pattern by using several basic clinical and laboratory data through an artificial intelligence algorithm. Data Mining is a technique which extracts information from data sets by using a combination of both statistical analysis methods and artificial intelligence algorithms. Also in this study, the decision tree and naivebayes classification algorithms of this technique were used. Firstly, sixty-five patients (mean age 51±7 years, 40 females,) were included in the study. Systolic and diastolic dipping were found in 13 and 15 % of the patients, respectively. In the advancing process of the experiment, the number of instances were reduced, because of some missing data of the patients. The data sets were tested using the J48 decision tree algorithm. This classification algorithm was implemented on 56 instances, and also the number of attributes was reduced from 35 to 23. 66 % of the instances (37) were reserved for training and 44 % of the instances (19) were reserved for testing. When the algorithm was run, the Non-Dipper/Dipper pattern of the instances were correctly predicted in a rate of 73.6842 %. Model was built in 0.02 seconds. This pilot study shows that a machine learning algorithm can help in the prediction of diurnal blood pressure pattern relying on some basic demographic, clinical and laboratory data, with a reasonable accuracy.

Angiotensin-converting enzyme gene polymorphism in arrhythmogenic right ventricular dysplasia: is DD genotype helpful in predicting syncope risk?

Introduction. Arrhythmogenic right ventricular dysplasia (ARVD) is a heritable disorder characterised by fibrofatty replacement of right ventricular myocytes and increased risk of ventricular arrhythmias and sudden cardiac death. Angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism affects myocardialACE levels. DD genotype favours myocardial fibrosis and is associated with malignant ventricular tachycardia.The aim of this study was to explore ACE gene polymorphism inARVD patients. Methods. Twenty-nine patients with ARVD and 24 controls were included.AllARVD patients had documented sustained ventricular tachycardia. Thirteen patients had syncopal episodes. Six patients were resuscitated from sudden cardiac death.ACE gene polymorphism was identified by polymerase chain reaction technique. Results. There was no significant difference in DD genotype frequency between ARVD patients and controls (44.8% vs. 45.8%, p=0.94). However, DD genotype frequency was significantly higher in ARVD patients with syncopal episodes compared to those without syncope (69.2% vs. 25.0%, p=0.017, odds ratio:6.750,95% confidence interval: 1.318—34.565). DD genotype was detected in higher frequency also in patients with a family history of sudden cardiac death (66.7% vs. 39.1%,p=0.36). Conclusion. High prevalence of DD genotype in ARVD patients with syncope suggests that ACE I/D polymorphism might be useful in identifying high-risk patients for syncope.

The Role of G Protein β3 Subunit Polymorphisms C825T, C1429T, and G5177A in Turkish Subjects with Essential Hypertension

Hypertension is a multifactorial disorder that constitutes a major risk factor for the cardiovascular system. Heterotrimeric G-proteins, which couple receptors for diverse extracellular enzymes or ion channels, are correlated with disease mechanisms. Several studies have demonstrated an association between G protein polymorphisms and essential hypertension in some populations, although contradictive results also exist. In this study, we have investigated the potential role of the C825T, C1429T, and G5177A polymorphisms of the β3 subunit of G-proteins in essential hypertension in a group of Turkish subjects. Genomic DNA from 106 normotensive individuals (117.4 ± 13.1, 75.2 ± 10.5; systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels, respectively) and 101 hypertensive subjects (152.3 ± 18.0, 92.5 ± 11.6; SBP and DBP levels, respectively) were studied by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing methods for these polymorphisms. Allele frequencies of the polymorphisms were consistent with Hardy Weinberg equilibrium, except for the C825T polymorphism (χ2 = 7.8). The frequencies of the 825T and 1429T variants were higher in hypertensive subjects compared to those of controls. Differences between hypertensives and controls were not statistically significant, though difference was very close to significance for C825T (p = 0.056 and 0.099 for 825T and 1429T, respectively). T allele frequency in overall population showed significant association with hypertension for C825T (0.0134). The prevalence of the 5177A-variant was very low and all subjects carrying it were heterozygotes in both groups.

Investigation of the Association Between Dopamine D1 Receptor Gene Polymorphisms and Essential Hypertension in a Group of Turkish Subjects

Dopamine has been shown to influence blood pressure by regulating renal sodium excretion through direct interaction with the dopamine receptors, especially with the Dopamine D1 receptor (DRD1). To better understand the role of polymorphisms in those effects, we investigated the association between two polymorphic sites in the DRD1 promoter region (A–48G, G–94A) and essential hypertension in the Turkish population. The DRD1 variants were genotyped by restriction fragment length polymorphism (RFLP) analysis. A total of 205 unrelated individuals were enrolled in the study. We found that genotype distributions and allele frequencies of the control and hypertensive subjects were very similar and did not show any significant difference with respect to blood pressure (BP) and hypertension. Contribution of the gene variances in BP or hypertension by sex differences and dependence on body mass index (BMI) were also evaluated. Distribution of genotypes and allele frequencies were found to be in line with previous reports. However, increments detected in hypertensive subjects were far from being statistically significant.