High Level of Real Urban Air Pollution Promotes Cardiac Arrhythmia in Healthy Mice

Background and Objectives@#Ambient particulate matter (PM) in real urban air pollution (RUA) is an environmental health risk factor associated with increased cardiac events. This study investigated the threshold level to induce arrhythmia, as well as arrhythmogenic mechanism of RUA that mainly consisted of PM <2.5 μm in aerodynamic diameter close to ultrafine particles. @*Methods@#RUA was artificially produced by a lately developed pyrolysis based RUA generator.C57BL/6 mice were divided into 4 groups: a control group (control, n=12) and three groups with exposure to RUA with the concentration of 200 µg/㎥ (n=12), 400 µg/㎥ (n=12), and 800 µg/㎥ (n=12). Mice were exposed to RUA at each concentration for 8 hr/day and 5 day/week to mimic ordinary human activity during 3 weeks. @*Results@#The QRS and QTc intervals, as well as intracellular Ca2+ duration, apicobasal action potential duration (APD) gradient, fibrosis, and inflammation of left ventricle of mouse hearts were increased dose-dependently with the increase of RUA concentration, and significantly increased at RUA concentration of 400 µg/㎥ compared to control (all p<0.001). In mice exposed to RUA concentration of 800 µg/㎥ , spontaneous ventricular arrhythmia was observed in 42%, with significant increase of inflammatory markers, phosphorylated Ca2+ /calmodulindependent protein kinase II (CaMKII), and phospholamban (PLB) compared to control. @*Conclusions@#RUA could induce electrophysiological changes such as APD and QT prolongation, fibrosis, and inflammation dose-dependently, with significant increase of ventricular arrhythmia at the concentration of 400 µg/㎥ . RUA concentration of 800 µg/㎥ increased phosphorylation of CaMKII and PLB.

High Level of Real Urban Air Pollution Promotes Cardiac Arrhythmia in Healthy Mice

Background and Objectives@#Ambient particulate matter (PM) in real urban air pollution (RUA) is an environmental health risk factor associated with increased cardiac events. This study investigated the threshold level to induce arrhythmia, as well as arrhythmogenic mechanism of RUA that mainly consisted of PM <2.5 μm in aerodynamic diameter close to ultrafine particles. @*Methods@#RUA was artificially produced by a lately developed pyrolysis based RUA generator.C57BL/6 mice were divided into 4 groups: a control group (control, n=12) and three groups with exposure to RUA with the concentration of 200 µg/㎥ (n=12), 400 µg/㎥ (n=12), and 800 µg/㎥ (n=12). Mice were exposed to RUA at each concentration for 8 hr/day and 5 day/week to mimic ordinary human activity during 3 weeks. @*Results@#The QRS and QTc intervals, as well as intracellular Ca2+ duration, apicobasal action potential duration (APD) gradient, fibrosis, and inflammation of left ventricle of mouse hearts were increased dose-dependently with the increase of RUA concentration, and significantly increased at RUA concentration of 400 µg/㎥ compared to control (all p<0.001). In mice exposed to RUA concentration of 800 µg/㎥ , spontaneous ventricular arrhythmia was observed in 42%, with significant increase of inflammatory markers, phosphorylated Ca2+ /calmodulindependent protein kinase II (CaMKII), and phospholamban (PLB) compared to control. @*Conclusions@#RUA could induce electrophysiological changes such as APD and QT prolongation, fibrosis, and inflammation dose-dependently, with significant increase of ventricular arrhythmia at the concentration of 400 µg/㎥ . RUA concentration of 800 µg/㎥ increased phosphorylation of CaMKII and PLB.

Long-Term Prognosis of Patients with an Implantable Cardioverter-Defibrillator in Korea

PURPOSE: The objective of this study was to elucidate the long-term prognosis of patients with implantable cardioverter-defibrillators (ICDs) in Korea. MATERIALS AND METHODS: We enrolled 405 patients (age, 57.7±16.7 years; 311 men) who had undergone ICD implantation. The patients were divided into three groups: heart failure (HF) and ICD for primary (group 1, n=118) and secondary prevention (group 2, n=93) and non-HF (group 3, n=194). We compared appropriate and inappropriate ICD therapy delivery among the groups and between high- (heart rate ≥200 /min) and low-rate (<200 /min) ICD therapy zones. RESULTS: During the follow-up period (58.9±49.8 months), the annual appropriate ICD therapy rate was higher in group 2 (10.4%) than in groups 1 and 3 (6.1% and 5.9%, respectively, p<0.001). There were no significant differences in annual inappropriate ICD therapy rate among the three groups. In group 1, the annual appropriate ICD therapy rate was significantly lower in patients with a high-rate versus a low-rate therapy zone (4.5% and 9.6%, respectively, p=0.026). In group 3, the annual inappropriate ICD therapy rate was significantly lower in patients with a high-rate versus a low-rate therapy zone (3.1% and 4.0%, respectively, p=0.048). CONCLUSION: Appropriate ICD therapy rates are not low in Korean patients with ICD, relative to prior large-scale studies in Western countries. Appropriate and inappropriate ICD therapy could be reduced by a high-rate therapy zone in patients with HF and ICD for primary prevention, as well as non-HF patients, respectively.

Focal Atrial Tachycardia Arising from the Inferior Vena Cava

The inferior vena cava (IVC) is a rare site of focal atrial tachycardia (AT). Here, we report a 20-year-old woman who underwent catheter ablation for anti-arrhythmic drug-resistant AT originating from the IVC. She had undergone open-heart surgery for patch closure of an atrial septal defect 17 years previously and permanent pacemaker implantation for sinus node dysfunction 6 years previously. The AT focus was at the anterolateral aspect of the IVC-right atrial junction, and it was successfully ablated under three-dimensional electroanatomical-mapping guidance. We suspect that the mechanism of this tachycardia was associated with previous IVC cannulation for open-heart surgery.

The Role of Preoperative NT-proBNP in Elderly Orthopedic Patients with Normal Left Ventricular Systolic Function / 대한내과학회지

BACKGROUND/AIMS: Preoperative N-terminal pro-brain natriuretic peptide (NT-proBNP) is a useful predictor of postoperative cardiovascular complications. The present study investigated whether blood NT-proBNP values are suitable for predicting postoperative cardiovascular complications after non-cardiac surgery in elderly patients showing normal left ventricular (LV) function on preoperative echocardiograms. METHODS: This study was performed by analyzing the medical records of elderly patients referred to the cardiology department for the purpose of assessing their cardiac function before orthopedic surgery. Of the patients who underwent echocardiography and NT-proBNP assessment simultaneously, 275 patients aged > or = 70 years and with an LV ejection fraction of > or = 55% were included in the study. RESULTS: Major adverse cardiac and cerebrovascular events (MACCEs) occurred in 33 (12%) of the 275 patients, and the NT-proBNP concentration was higher in patients with complications than in those without complications (1,904.20 +/- 2,300.23 vs. 530.58 +/- 882.27 pg/mL, p 80 years (odds ratio, 2.313; p = 0.047) and an increased blood NT-proBNP concentration (odds ratio, 3.189; p = 0.009) were independent risk factors for the prediction of MACCEs. CONCLUSIONS: Although elderly patients scheduled to undergo non-cardiac surgery may show normal LV systolic function on echocardiography, measurement of their preoperative blood NT-proBNP concentration is useful for predicting MACCEs occurring after non-cardiac surgery.

Autoimmune thyroiditis with minimal change disease presenting acute kidney injury / 영남의대학술지

Autoimmune thyroiditis is the most common cause of hypothyroidism in the world. It is characterized clinically by gradual thyroid failure, goiter formation, or both, because of the autoimmune-mediated destruction of the thyroid gland. Renal involvement presenting proteinuria in autoimmune thyroiditis is not uncommon, occurring in 10% to 30% of the cases. Glomerulonephropathy associated with autoimmune thyroiditis, however, is a rare disease. Most reports of autoimmune thyroiditis with glomerulonephropathy have demonstrated a mixed pathological morphology and have been predominantly associated with membranous glomerulopathy. The case of minimal-change disease associated with thyroiditis presenting acute kidney injury is a rare disease that has not been reported in South Korea. Reported herein is the case of a 16-year-old man diagnosed with Hashimoto's thyroiditis, with minimal-change disease presenting acute kidney injury. He revealed hypothyroidism, proteinuria, and impaired renal function. Renal biopsy showed minimal-change disease and minimal tubular atrophy. The patient was treated with thyroid hormone, and his renal function and proteinuria improved. Therefore, for patients with autoimmune thyroiditis presenting unexplained proteinuria, glomerulonephropathy should be ruled out. Conversely, for patients with glomerulonephropathy and persistent proteinuria despite proper treatment, thyroid function and antibody tests should be performed.