No abstract available.
Angiotensins* ; Atrial Fibrillation* ; Blood Pressure* ; Stroke*

No abstract available.
Bundle-Branch Block ; Heart Failure ; Heart ; Humans

The Korean National Health Information Database (NHID) contains nationwide claims data, including sociodemographic data, health care utilization, health screening data, and healthcare provider information. To compensate for the limitations of randomized clinical trials, real-world observational studies using claims data have emerged as a novel research tool. We summarized the structure of the Korean NHID and the recent researches conducted in the field of cardiovascular science. Epidemiological studies, prescription patterns, temporal trends, comparison of effectiveness and safety of treatments, variability index using laboratory data, and rare intractable disease constitute interesting topics of research in cardiovascular science using the NHID. The operational definition of covariates and clinical outcomes is important for researchers interested in using the NHID data as new tools to prove their hypothesis. A step-by-step approach adopted by a team of data scientists, epidemiologists, statisticians, and clinical researchers may be most effective while designing research studies. The ultimate direction of research using the NHID should aim to improve the welfare of the public by promoting public health, reducing medical costs, and guiding healthcare policies.

BACKGROUND AND OBJECTIVES: Major epicardial fat pads contain cardiac ganglionated plexi (GP) of the autonomic nervous system. Autonomic denervation may improve the success rate of atrial fibrillation (AF) ablation. This study was designed to elucidate the acute effects of blocking the right atrium-pulmonary vein (RA-PV) and left atrium-inferior vena cava (LA-IVC) fat pads on the electrophysiologic characteristics of the atrium and AF inducibility with a botulinum toxin injection. Materials and Methods: Eight mongrel dogs were studied. The RA-PV and LA-IVC fat pads were exposed through a median thoracotomy. Botulinum toxin (BT, 50 U to each fat pad, n=6) or normal saline (NS, n=2) was injected in the entire area of two fat pads. The study protocol was applied before injection and repeated at 1, 2, 3, 4, and 5 hours thereafter. The sinus rate, ventricular rate during rapid atrial pacing with a cycle length of 50 ms, and AF inducibility were measured with and without vagal stimulation (VS). Bilateral cervical VS was applied (20 Hz, 0.2 ms, 5.6+/-2.0 V). AF inducibility was evaluated with burst pacing with 200 impulses at a 50-ms cycle length. RESULTS: VS effects on the sinus node and AF inducibility were eliminated a few hours after injection of BT; these changes were not observed after injection of NS. CONCLUSION: Short-term autonomic denervation of the atria was achieved by blocking the major epicardial GP with BT.
Adipose Tissue ; Animals ; Atrial Fibrillation ; Autonomic Denervation ; Autonomic Nervous System ; Autonomic Pathways ; Botulinum Toxins ; Dogs ; Ganglion Cysts ; Sinoatrial Node ; Thoracotomy ; Veins

A 43-year-old man who had received mitral and aortic valve replacement surgery underwent the implantation of an implantable cardioverter defibrillator (ICD) for sustained ventricular tachycardia. The patient presented with a sudden jolting sensation in his left upper chest area one year after the device implantation. He had a history of vigorous upper body exercise during the several months of the follow-up period. Device interrogation revealed complete sensing and capture failure. The ventricular lead impedance was in the normal range, but the high voltage impedance had dropped to less than 10 Ω. Four inappropriate shocks for ventricular fibrillation had been delivered due to over-sensing of the atrial signal on the ventricular lead. Chest radiography showed ventricular lead displacement with extreme rotation and flipping-over of the generator. In the lead revision operation, the old ventricular lead was extracted and replaced, and the generator was fixed more deeply in the pocket with a non-absorbable ligature.
Adult ; Aortic Valve ; Defibrillators ; Defibrillators, Implantable* ; Electric Impedance ; Follow-Up Studies ; Humans ; Ligation ; Radiography ; Reference Values ; Sensation ; Shock* ; Tachycardia, Ventricular ; Thorax ; Ventricular Fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice and has been a major public health problem. The prevalence of AF globally has been reported to range from 0.4% to 2% in the adult population; however, the prevalence widely varies depending on the study population. Although AF prevalence in Asian population is about 1% lower than that in European and North American population, the number of AF patients in Asia is rapidly increasing concomitant with the increased aging of the population. However, previous studies that reported AF epidemiology in the Korean population are limited. According to a recent report based on the national health claims database, prevalence of AF in 2015 was 0.7% in the entire Korean adult population and showed a continuous increase with population aging. Additionally, among patients with AF, mean CHA2DS2-VASc score was significantly increased and the number of high thromboembolic risk patients has increased over time. Although oral anticoagulation (OAC) prescription in AF patients increased from 35% to 51%, especially after introduction of non-vitamin K antagonist anticoagulants, a substantial proportion of Korean patients with AF still remain undertreated. In this review, we aimed to summarize temporal changes in the prevalence and incidence of AF and to evaluate the thromboembolic risk in patients with AF. In addition, we also discussed the utilization of OAC therapy in patients with AF in Korean population.
Adult ; Aging ; Anticoagulants ; Arrhythmias, Cardiac ; Asia ; Asian Continental Ancestry Group ; Atrial Fibrillation* ; Epidemiology ; Humans ; Incidence ; Prescriptions ; Prevalence* ; Public Health ; Stroke

BACKGROUND: Although impaired endothelial function is well known in patients with diabetes mellitus, the precise mechanism and the factors that contribute to this dysfunction remain to be clarified. We examined the effect of acute hyperglycemia on patients with impaired glucose metabolism in vivo by plethysmography. METHODS: Seven patients with diabetes mellitus or impaired glucose metabolism were studied. In each patient, endothelial function was examined in the fasting state and at two levels of hyperglycemia, which were achieved by the infusion of glucose, insulin, and somatostatin. Forearm blood flow was measured while acetylcholine was infused in increasing concentrations(7.5, 15, and 30 microgram/min) through the brachial artery. RESULTS: Glucose concentrations increased accordingly at each stage, from 135.3+/-18.4 mg/dl at stage 1(the fasting state), to 239.0+/-15.2 mg/dl at stage 2(the first level of hyperglycemia), and to 378.3+/-25.3 at stage 3 (the second level of hyperglycemia) [p<0.01]. Maximal acetylcholine-dependent vasodilation achieved by infusion of acetylcholine at 30 microgram/min was significantly aftenuated during stages 2 and 3 compared with stage 1(p<0.05 by AVOVA; forearm blood flow ratio was 2.87+/-0.18 and 2.56+/-0.14 versus 3.58+/-0.21, respectively). This was also evident during the infusion of 15 microgram/min and 7.5 microgram/min of acetylcholine. CONCLUSIONS: Endothelium-dependent vasodilation is significantly aftenuated by acute hyperglycemia in patients with diabetes mellitus or impaired glucose metabolism. Our findings suggest that elevated glucose may contribute to the endothelial dysfunction observed in patients with diabetes mellitus or impaired glucose metabolism.
Acetylcholine ; Brachial Artery ; Diabetes Mellitus* ; Endothelium ; Fasting ; Forearm ; Glucose* ; Humans ; Hyperglycemia* ; Insulin ; Metabolism* ; Plethysmography ; Somatostatin ; Vasodilation*