Mehmet Melek

The Effects of Vitamin D Deficiency on Atrial Fibrillation

Background: Vitamin D deficiency is associated with cardiovascular disease such as coronary artery disease, heart failure, and hypertension. Vitamin D deficiency activates the renin–angiotensin–aldosterone system, which affects the cardiovascular system. For this reason, it could be suggested that there is a relationship between vitamin D deficiency and atrial fibrillation (AF). In our study, we compared 25-hydroxyvitamin D (25-OHD) levels between nonvalvular AF, valvular AF, and control groups in sinus rhythm. Method: A total of 102 patients with nonvalvular chronic AF without any other cardiovascular disease (mean age 62.51 ± 5.88; group I) and 96 patients with AF, which is associated with mitral valve disease (mean age 61.51 ± 5; group II) were included in our study. Of all, 100 age-matched healthy people with sinus rhythm were accepted as control groups (mean age 61.35 ± 5.44). Routine biochemical parameters, 25-OHD and parathormone levels were performed. Results: Baseline characteristics of the study groups were comparable. Group I patients had a lower vitamin D level than group II and the control group (6.51 ± 4.89, 9.24 ± 7.39, and 11.18 ± 6.98 ng/mL, P < .001, respectively). In groups I and II, the patients’ left atrium diameter and systolic pulmonary artery pressure are higher than the control group. Conclusion: As a result, our study revealed a relationship between vitamin D deficiency and nonvalvular AF.

Predictive value of atrial electromechanical delay for atrial fibrillation recurrence

BACKGROUND We investigated the predictive value of atrial electromechanical delay (AEMD) for recurrence of atrial fibrillation (AF) at 1-month after cardioversion. METHODS Seventy-seven patients with persistent AF were evaluated and finally 50 patients (12 men, 38 women) were included. All patients underwent transthoracic electrical DC cardioversion under amiodarone treatment. AEMD was measured as the time interval from the onset of the P wave on electrogram (ECG) to the beginning of late diastolic wave (Am) from the ventricular annulus and atrial walls on tissue Doppler imaging, in the apical 4-chamber view 24 h after cardiversion. P wave maximum-duration (Pmax), P wave minimum-duration (Pmin) and P wave dispersion-duration (Pdis) were calculated on the 12-lead ECG at 24-h postcardioversion. We followed the heart rate and rhythm by 12-lead ECG at 24-h, 1-week and 1-month. RESULTS At 1-month follow-up after cardioversion, 28 (56%) patients were in sinus rhythm (SR), whereas 22 (44%) patients reverted to AF. The AEMD durations were longer in AF group than SR group (p < 0.001) and were signifi cantly correlated with Pmax and Pdis (p < 0.001 for both). For AF recurrence; duration of AF, left atrial (LA) diameter, maximum LA volume index, mitral A velocity and LA lateral AEMD were significant parameters in univariate-analysis, however LA lateral AEMD was the only significant parameter in multivariate-analysis (OR: 1.46; 95% CI 1.02-2.11; p = 0.03). CONCLUSIONS Our results suggest that AEMD is associated with an increased risk of recurrence of AF within 1-month. These data may have implications for the identification of patients who are most likely to experience substantial benefit from cardiversion therapy for AF.

The effects of eosinophil on the left atrial thrombus in patients with atrial fibrillation.

Background: Atrial fibrillation (AF) is the most common cardiac rhythm disorder. Atrial fibrillation causes a 5-fold increased risk for thromboembolic stroke. It is known that eosinophils play an important role in thrombosis. We aimed to compare the number of eosinophil counts of the patients with and without thrombi in the left atrium (LA) or in the left atrial appendage (LAA) and to ascertain the association of eosinophil counts with the presence of thrombi. Method: The study included 89 patients diagnosed with persistent AF who underwent transesophageal echocardiography and designated to undergo cardioversion. The patients were divided into 2 groups: group 1 consisted of 40 patients (18 male; average age 63.27 ± 1.4) who had thrombus formation in the LA or LAA, and group 2 consisted of 49 patients (23 male; average age 66.53 ± 1.56) who did not have any thrombus in the LA or LAA. These patients underwent concurrent routine biochemical tests and eosinophil count on whole blood count was also performed. Results: Baseline characteristics of the study groups were comparable. Group 1 patients had higher eosinophil and mean platelet volume values than group 2 (233.0 ± 30.7 vs 118.9 ± 11.8 and 9.77 ± 0.20 vs 8.27 ± 0.12 fL, P < .001, respectively). In group 1, the patients’ LA diameter is higher than that in group II. Conclusion: As a result, our study revealed a relationship between eosinophil count and LA thrombus in patients with nonvalvular AF.

The effect of varenicline on Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio in healthy smokers and nonsmokers

BACKGROUND Varenicline could affect the T wave and QT interval. The interval from the peak to the end of the electrocardiographic (ECG) T wave (Tp-e) may correspond to the transmural dispersion of repolarization, and increased Tp-e interval and Tp-e/QT ratio are associated with malignant ventricular arrhythmias. In this study, we assessed the effects of varenicline on Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio. METHODS Thirty healthy volunteers (15 healthy non-smokers [NS] and 15 healthy smokers [S]) were included in the randomized, double-blind, placebo-controlled, crossover study. Varenicline (2 mg single dose) or placebo was administered in two different testing sessions (5 days after the first period, performed the second period). Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio were assessed in the supine position and during handgrip exercise before and after the participants were given placebo or varenicline. Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio were calculated from continuous ECG recordings and averages were used in the final analysis. RESULT There were no statistically significant differences among any of the Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio before and after placebo administration in both groups (S and NS). In the S group, Tp-e and QTc interval, and Tp-e/QT and Tp-e/QTc ratio were significantly increased after varenicline administration (Tp-e: 64.28 ± 8.78 vs. 70.42 ± ± 13.12; p = 0.02, QTc: 409.57 ± 28.17 vs. 425.28 ± 32.79; p = 0.02, Tp-e/QT: 0.18 ± 0.02 vs. 0.19 ± 0.03; p = 0.04, Tp-e/QTc: 0.17 ± 0.02 vs. 0.19 ± 0.02; p = 001) but these parameters were not changed in the NS group. CONCLUSIONS Tp-e and QTc interval, and Tpe/QT and Tpe/QTc ratio were increased after varenicline administration in smokers.

A Comparison of Two Electrophysiology Centers in Different Social And Economic Regions Of Turkey During First Quarter of the Year

Introduction: More and more patients have been undergoing electrophysiological study (EPS) as the number of rhythmologists have increased. Due to the increased interest in the study, today EPS applications are made even in second step public hospitals or private hospitals. Our aim is to compare two electrophysiology labs, that are in different regions with social and economic development, in terms of patient demography, diagnosis, amount of diagnostic and curative interventions. Materials and Methods: In this study, two centers from two different regions of Turkey were selected; a training and research center (center 1) in the Western part and a public hospital (center 2) in the Eastern part of the country. Records of the patients who undergone EPS in these two centers were retrospectively analyzed. Independent parametric data were evaluated by T-test, and categorical data via Mann-Whitney U test. A p value below 0.05 was accepted for significance. Results: A total of 83 patients were retrospectively analyzed (42 from center 1, 41 from center 2). Patients’ baseline demographic data was similar except intellectual status. Nevertheless, both groups differed based on the number of patients with diagnosis of atrioventricular reciprocating tachycardia (p=0.047). There was a significant difference in procedure types. Center 1 performed significantly higher number of curative procedures (p=0.039) than center 2. Conclusions: Nowadays, EPS is spread from specialized centers to middle-sized hospitals. Since specialized centers have more access to the advanced devices such as electro-anatomic mapping rather than conventional equipment, they are evaluating more complex cases with a variety of different diagnosis. Constructing a referral system from peripheral hospitals to distinguished centers in electrophysiology field would eliminate unnecessary and/or repeated procedures and decrease the expenses.

OP-105 RENAL SYMPATHETIC DENERVATION FOR RESISTANT HYPERTENSION AND DOUBLE LEFT RENAL ARTERY ABLATION

Background: Hypertension is a major global health problem. An estimated 25–30% of the adult population in the world suffer from this condition. Resistant hypertension is defined as when a treatment that has included attention to lifestyle measures and the prescription of at least three drugs (including a diuretic) in adequate doses has failed to lower systolic and diastolic blood pressure to goal. Prevalence of resistant hypertension is nearly 10%. Percutaneous renal sympathetic denervation is a novel approach for resistant hypertension treatment. Method: Renal sympathetic denervation was performed for three patients who had resistant hypertension. For renal denervation first of all renal arteries canulate with 6F guidewire (RDC-I, Vista britetip, Cordis, FL, USA), then we performed renal angiography and showed that renal arteries size (diameter >4mm, length >30mm). We performed renal denervation with renal denervation catheter (RDN 006, Symplicity Catheter, Ardian, Inc, USA). The third patient had double left renal artery (Figure 1); we performed renal denervation for both left renal artery. At the end of the denervation we performed renal angiography and showed the denervation points. Results: Patients characteristics, treatment, procedural characteristics, plasma renin activity and norepinephrine values are shown in Table 1. Three patients were followed in terms of blood pressure and complications for 6 months and we achieved target blood pressure for the first and second patients and the number of antihypertensive drugs were reduced (the antihypertensive drug number reduced from 6 to 3 for the first patient and reduced from 6 to 4 for the second patient) (Table 1). We have not achieved target blood pressure for the third patient yet. Conclusion: Renal denervation was performed successfuly and blood pressure was significantly decreased in patients with resistance hypertension. More data are needed to investigate the usefulness of renal denervation procedure in the management of the double renal artery.