Prognostic impact of oral anticoagulation therapy and atrial fibrillation in patients with type B acute aortic dissection.

Background: The prognostic impact of atrial fibrillation (AF) and oral anticoagulation (OAC) therapy in patients with type B acute aortic dissection (AAD) remains unclear. Therefore, we investigated the prognostic impact of AF and OAC therapy in patients with type B AAD. Methods: Consecutive patients diagnosed with AAD were included in this single-center, retrospective study. Patients with type B AAD were selected from the study population and divided into three groups: AF(+)/OAC(+), AF(+)/OAC(-), and AF(-)/OAC(-). The primary end point was major adverse cardiovascular and cerebrovascular events (MACCE), including all-cause death, progressive aortic events, cerebral infarction, and organ malperfusion. Results: In total, 139 patients diagnosed with type B AAD were analyzed. AF was observed in 27 patients (19%). Among them, 13 patients (9%) received OAC therapy for AF. MACCE occurred in 32 patients (23%) during the observation period: all-cause death in four patients, progressive aortic events in 24 patients, cerebral infarction events in two patients, and malperfusion events in two patients. The incidence of MACCE was higher in the AF(+)/OAC(+) group than in the AF(+)/OAC(-) group (hazard ratio[HR]: 3.875; 95% confidence interval [CI]: 1.153-17.496). In contrast, there was no significant difference in the incidence of MACCE between the AF(+)/OAC(-) and AF(-)/OAC(-) groups (HR: 1.001, 95% CI: 0.509-1.802). Conclusion: Among patients with type B AAD, the use of OAC for AF was associated with a higher risk of MACCE.

Fibroblasts activation by embryonic signal switching: A novel mechanism of placental growth factor-induced cardiac remodeling.

INTRODUCTION: Cardiac remodeling is defined as cellular interstitial changes that lead dysfunction of the heart after injury. Placental growth factor (PlGF), a member of the VEGF family, has been reported to regulate cardiac hypertrophy in hemodynamic state. We therefore analyze the function of PlGF during cardiac remodeling using cardiac cells and fibroblasts, under Angiotensin II (AngII) stimulation. METHODS: PlGF overexpressed mouse embryonic fibroblasts derived from C57BL/6 mice, were made by deficient retrovirus vector, designated as C57/PlGF. Only retrovirus vector introduced C57 cells (C57/EV) were used as control. After AngII stimulation, wound scratching assay and MTT proliferation assay with or without p38 MAPK inhibitor, SB205580 were performed in retrovirally-introduced C57 cells. Reactive oxygen species (ROS) production, NF-kB activation, IL-6 and TNF-α production were also measured. Then we assessed AngII-induced cell proliferation of mouse cardiac fibroblasts (CFs) and rat primary cardiomyocytes incubating with C57/PlGF conditioned-medium. RESULTS: The PlGF production in C57/PlGF were confirmed by ELISA (1093.48 ± 3.5 pg/ml, ±SE). AngII-induced cell migration, proliferation and H2O2 production were increased in C57/PlGF compared with C57/EV. SB205580 inhibited the AngII-induced cell proliferation in C57/PlGF. In C57/PlGF cells, NF-kB activation was higher, followed by up-regulation of IL-6 and TNF-α production. CFs and cardiomyocytes proliferation increased when stimulated with C57/PlGF conditioned-medium. DISCUSSION: The activation of fibroblast is stimulated by PlGF signaling via p38 MAPK/NF-kB pathway accompanied by elevation of ROS and inflammatory response. Furthermore, these signals stimulate the activation of CFs and cardiomyocytes, indicating that high circulating level of PlGF have a potential to regulate cardiac remodeling.

"Honey pot"-like lesion formation: Impact of catheter contact angle on lesion formation by novel diamond-embedded temperature-controlled ablation catheter in a porcine experimental model.

BACKGROUND: Novel diamond-embedded catheter enables precise temperature-controlled ablation. However, the effects of contact angle on lesion formation of this catheter are poorly understood. OBJECTIVE: The purpose of this study was to evaluate lesion formation using the temperature-controlled ablation catheter embedded with diamond at different angles in a porcine experimental model. METHODS: Freshly sacrificed porcine hearts were used. Radiofrequency catheter ablation was performed at 50 W for 15 seconds at an upper temperature setting of 60°C. The contact force (5g, 10g, 30g) and catheter contact angles (30°, 45°, 90°) were changed in each set (n = 13 each). Surface width, maximum lesion width, lesion depth, surface area, distance from the distal edge to the widest area, and impedance drop were evaluated. RESULTS: Surface width and maximum lesion width were longer at 30° than at 90° (P <.05). There were no significant differences in the lesion depth by catheter angle except at 30g. Surface area was larger at 30° than at 90° (P <.05). Distance from the distal edge to the widest area was longer at 30° than at 90° (P <.05). There were no significant differences in impedance drop according to catheter angle. CONCLUSION: With diamond-embedded temperature-controlled ablation catheters, lesion width increased at a shallower contact angle, whereas lesion depth did not. Surface area also increased at a shallower contact angle. This catheter created a large ablation lesion on the proximal side of the catheter, which looked like a "honey pot."

Steerable esophageal thermometer for atrial fibrillation ablation in a patient with esophageal achalasia: a case report.

Esophageal injury is a major concern during catheter ablation of atrial fibrillation. Operators avoid radiofrequency applications on the esophagus by changing ablation line; however, it is unavoidable in patients with a dilated esophagus, such as esophageal achalasia. Steerable esophageal thermometer is useful for evaluating precise temperatures to prevent esophageal injury.