Biophysical evaluation of clinical bipolar radiofrequency ablation approaches in a porcine ex-vivo model

Abstract Funding Acknowledgements Type of funding sources: None. Background Bipolar radiofrequency catheter ablation (BA) is an important therapeutic option for therapy refractory ventricular arrhythmias. BA approaches may frequently include titration of energy from lower to higher levels and target epicardial sites with overlying fat tissue. However, the actual effect on lesion formation has not been evaluated. Purpose Investigating lesion modalities during BA (a) using low-to-high energy titration, (b) conducting prior sequential unipolar ablation additional to BA and (c) in epicardial fat tissue. Methods An ex-vivo model consisting of freshly explanted swine hearts positioned in a circulating temperature-controlled saline bath was established. An irrigated active and ground ablation catheter with a 3.5mm tip connected to a novel single generator capable of performing BA were positioned on both sides of the left ventricular/ventricular septal myocardium orthogonal to respective swine tissue. Radiofrequency energy was applied with a fixed force of 10 g for 60 s using different approaches: (1) Titration group, BA of 30 W following BA of 50W; (2) sequential group, ablating unipolar from both catheters using 30 W; (3) epicardial fat group (fat thickness >1 cm) with BA of 50W; (4) sequential + BA group, applying unipolar energy of 30 W first on both catheters with consecutive BA of 50W; (5) control group, with BA of 30, 40 or 50 W only. Dimensions of set lesion as well as bipolar generator impedance during ablation were assessed. Results A total of 65 ablation lesions were analyzed. The mean tissue thickness was 18 ± 3 mm (range 11-23 mm), with a mean fat thickness of 3.5 ± 1.1 mm in the epicardial fat group. Overall, transmurality was observed in 17 lesions (26%) with the highest rates in the titration and sequential + BA group (75 / 100%), while no difference to the control group applying 50 W was detected (Kruskal-Wallis test, p = 0.30/0.19) and no lesion displaying transmurality in the epicardial fat group (p < 0.001). The maximum impedance drop during ablation was highest in the control group applying 50 W and lowest in the epicardial fat group (51 ± 24 vs 23 ± 12 Ω, p = 0.02). The lesion volume did not differ between titration and control group applying 50 W (455 ± 230 vs 426 ± 268 mm3, p > 0.99), whereas being significantly larger than in the epicardial fat group [median 59 (interquartile range 41-92 mm3), p = 0.02/0.01]. The sequential + BA group showed significantly increased lesion volume compared with both titration and control group [1401 (1093-1728) mm3, p = 0.004, Figure]. Eleven steam pops (17%) were registered with similar distribution between groups (p = 0.24). Conclusion Lesion dimensions were similar between the BA titration approach and BA solely applying 50 W. Prior sequential unipolar ablation may significantly increase ablation lesion volumes during BA. The effect of BA at sites of significant epicardial fat tissue >1 cm may be severely limited, which should be considered during procedure planning. Abstract Figure. Lesion dimensions in BA approaches

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Evaluation of epicardial fat tissue thickness and aortic stiffness in patients with gestational diabetes mellitus

Perinatal Journal ◽

10.2399/prn.21.0291006 ◽

2021 ◽

Vol 29 (1) ◽

pp. 33-38

Author(s):

Melike Nur Akın ◽

Burcu Kasap ◽

Fatih Akın ◽

Burak Sezgin ◽

İbrahim Altun ◽

...

Keyword(s):

Diabetes Mellitus ◽

Gestational Diabetes ◽

Gestational Diabetes Mellitus ◽

Pregnant Women ◽

Aortic Stiffness ◽

Epicardial Fat ◽

Control Group ◽

Fat Tissue ◽

Tissue Thickness ◽

Epicardial Fat Tissue

Objective We aimed to assess the relationship between gestational diabetes mellitus and coronary artery disease by measuring epicardial fat tissue thickness and aortic stiffness in pregnant women diagnosed with gestational diabetes mellitus. Methods 28 pregnant women diagnosed with gestational diabetes mellitus and 25 pregnant women without gestational diabetes mellitus were included in the research. Body mass index, laboratory values, blood pressure measurements and obstetric history findings of the study population were recorded. All participants of the study population were evaluated with transthoracic echocardiography between 24 and 28 weeks of gestational period. The measurement of epicardial fat tissue thickness was taken and aortic stiffness index was also calculated. Results The age, gravidity, parity and obstetric history of the two groups were similar. Epicardial fat tissue thickness was found significantly higher in gestational diabetes mellitus group than control group (0.416 cm and 0.336 cm, respectively; p<0.001). However, no significant difference was found in aortic stiffness measurements of the two groups (p=0.079). Conclusion According to the results of our study, epicardial fat tissue thickness was found to be statistically significantly higher in pregnant women with gestational diabetes mellitus compared to the control group. The fact that no difference was detected in other cardiovascular parameters suggests that measurement of epicardial fat tissue thickness in gestational period may be a beneficial adjunctive tool in early detection of gestational diabetes mellitus.

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The relationship between epicardial fat tissue thickness and transit time flow measurement values of coronary artery bypass grafts

Journal of Cardiovascular and Thoracic Research ◽

10.34172/jcvtr.2020.50 ◽

2020 ◽

Vol 12 (4) ◽

pp. 307-312

Author(s):

Hacı Ali Uçak

Keyword(s):

Coronary Artery ◽

Coronary Artery Bypass ◽

Artery Bypass ◽

Epicardial Fat ◽

Fat Tissue ◽

Epicardial Fat Thickness ◽

Graft Flow ◽

Time Flow ◽

Epicardial Fat Tissue ◽

Fat Thickness

Introduction: Epicardial fat tissue, the true visceral adipose depot of the heart, has been associated with changes in both cardiac function and morphology. This study aimed to show the relationship between epicardial fat tissue (EFT) thickness and graft flow dynamics in arterial and venous grafts in coronary artery bypass graft surgery (CABG). Methods: Patients underwent transthoracic echocardiography before surgery and epicardial fat thickness were evaluated. The patients were divided into two groups as EFT value <5.5 (group 1) mm and ≥5.5 (group 2) mm. One hundred eighty-one patients with a total of 434 grafts (162 arterial and272 venous) underwent isolated coronary artery bypass grafting surgery. All grafts were examined by transit time flow meter intraoperatively. Results: The mean epicardial fat tissue thickness values were 4.9±0.8 mm and 6.1±1.3 mm, respectively.Mean graft flow values of left internal mammary artery was 44.21±23.2 mL/min in group 1 and39.65 ± 19.2 mL/min in group 2 (P = 0.041). Similarly, mean graft flow values were higher in group1 in all venous grafts regardless of which vessel bypass was performed. There is a significant negative correlation between epicardial fat thickness and mean graft flow. Conclusion: Epicardial fat thickness measurement preoperatively might provide additional data for the faith of the graft.

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The role of epicardial fat tissue in atrial fibrillation onset in patients with hypertension

European Heart Journal ◽

10.1093/ehjci/ehaa946.0365 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

A Tarzimanova ◽

V.I Podzolkov ◽

M.V Pisarev ◽

R.G Gataulin ◽

K.A Oganesian

Keyword(s):

Atrial Fibrillation ◽

Plasma Concentration ◽

Sinus Rhythm ◽

Epicardial Fat ◽

Funding Source ◽

Fat Tissue ◽

Hypertensive Patients ◽

Group I ◽

Epicardial Fat Tissue ◽

Group Ii

Abstract Aim To study the influence of epicardial fat tissue (EFT) on atrial fibrillation (AF) occurrence in hypertensive patients. Materials and methods The study included 195 patients with hypertension aged from 38 to 72 years (mean age was 61.5±1.8 years). All patients were divided into two groups: group I included 95 hypertensive patients with paroxysmal AF; 100 patients with hypertension in sinus rhythm were enrolled into group II. Echocardiography was performed to evaluate the thickness of EFT in a parasternal long-axis view. The EFT volume was assessed with computed tomography (CT) scan. The plasma concentration of tissue inhibitor of metalloproteinase-1 (TIMP-1) and metalloproteinase-9 (MMP-9) was measured to evaluate the myocardial fibrosis process. Results There was no significant difference between the studied groups of patients in body mass index: 34.43±1.2 kg/m2 in group I vs 31.97±1.67 kg/m2 in the group II. Waist circumference was significantly higher in group I in comparison with the group II patients: 118.9±3.3 cm vs 110.2±1.4 cm, respectively (p=0.038). EFT thickness was significantly higher in patients with paroxysmal AF (11.6±0.8 mm) in comparison with the patients in sinus rhythm (8.6±0.4 mm) (p<0.001). In group I patients a significant increase of EFT volume (4.6±0.4) in comparison with II group (3.5±0.25) (p=0.002) was noted. A significant positive correlation was revealed in hypertensive patients with paroxysmal AF between EFT volume and left atrial (LA) volume (r=0.7, p=0.022). Also, the plasma concentrations of TIMP-1 and MMP-1 were significantly higher in patients with paroxysmal AF and hypertension. There was a strong positive correlation between EFT volume and plasma concentration of TIMP-1 (r=0.72; p=0.01) and between the EFT volume and the LA volume (r=0.7, p=0.022) in group I patients. Multivariate regression analysis revealed the significant influence of increased EFT thickness more than 10 mm (prevalence ratio (PR) 4.1; 95% CI 1.1; 15.6) and EFT volume more than 6 ml (PR 3.7; 95% CI 1.0; 14.2) on AF occurrence. Conclusion Increased EFT thickness (more than 10 mm) and EFT volume (more than 6 ml) are predictors of AF onset in hypertensive patients. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): The complex subject of the Department

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The relation between epicardial fat tissue thickness and atrial fibrillation ın hemodialysis patients

Seminars in Dialysis ◽

10.1111/sdi.12901 ◽

2020 ◽

Vol 33 (5) ◽

pp. 428-434

Author(s):

Fatma Betül Guzel ◽

Orcun Altunoren ◽

Hakan Gunes ◽

Muhammed Seyithanoglu ◽

Murat Kerkutluoglu ◽

...

Keyword(s):

Atrial Fibrillation ◽

Hemodialysis Patients ◽

Epicardial Fat ◽

Fat Tissue ◽

Tissue Thickness ◽

Epicardial Fat Tissue

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Is there a relationship between serum paraoxonase level and epicardial fat tissue thickness?

Anadolu Kardiyoloji Dergisi/The Anatolian Journal of Cardiology ◽

10.5152/akd.2014.4742 ◽

2014 ◽

Vol 14 (2) ◽

pp. 115-120 ◽

Cited By ~ 1

Author(s):

Ahmet Goktug Ertem ◽

Ali Erayman ◽

Tolga Han Efe ◽

Bilge Duran Karaduman ◽

Halil Ibrahim Aydin ◽

...

Keyword(s):

Epicardial Fat ◽

Fat Tissue ◽

Tissue Thickness ◽

Epicardial Fat Tissue ◽

Serum Paraoxonase

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Relationship between neutrophil/lymphocyte ratio and epicardial fat tissue thickness in patients with newly diagnosed hypertension

Journal of International Medical Research ◽

10.1177/0300060517749130 ◽

2018 ◽

Vol 46 (3) ◽

pp. 940-950 ◽

Cited By ~ 6

Author(s):

Mehmet Ali Derya ◽

Vahit Demir ◽

Huseyin Ede

Keyword(s):

Blood Pressure ◽

Healthy Subjects ◽

Control Group ◽

Newly Diagnosed ◽

Fat Tissue ◽

Tissue Thickness ◽

Neutrophil Lymphocyte Ratio ◽

Lymphocyte Ratio ◽

Epicardial Fat Tissue ◽

The Relationship

Objective Epicardial fat tissue thickness (EFT) and the neutrophil/lymphocyte ratio (NLR) are associated with atherosclerosis. Few studies have focused on the relationship between these parameters in patients with newly diagnosed hypertension. In this study, we examined the relationship between EFT and the NLR in patients with newly diagnosed hypertension detected by 24-hour ambulatory blood pressure monitoring (ABPM). Methods Eighty consecutive patients without chronic illness who were diagnosed with hypertension according to ABPM results and 80 otherwise healthy subjects were enrolled in the study. EFT of each participant was measured echocardiographically. The C-reactive protein (CRP) concentration and NLR were measured from venous blood samples. Results The 24-hour average systolic blood pressure was significantly higher in the hypertension group than in the control group (143±17 vs. 117±7 mmHg, respectively). There were no significant differences in age, sex, or body mass index between the two groups. EFT, the NLR, and the CRP concentration were significantly higher in the hypertension group than control group. Additionally, a significantly positive correlation between EFT and the NLR was found in both the control group and hypertension group. Conclusion A higher EFT and NLR were detected in patients with newly diagnosed hypertension than in healthy subjects.

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