Treatment of cardiac disease via the epicardium fell under the domain of cardiac surgery due to the need for an open thoracotomy. Since an open thoracotomy is invasive in nature and has the potential for complications, a minimally invasive and percutaneous approach would be more attractive for suitable patients. The recent success of epicardial ablation of refractory arrhythmia via the percutaneous pericardial approach has increased the potential for delivery of epicardial therapies. Epicardial ablation has increased the success and safety since anti-coagulation and transseptal catheterization for left atrial arrhythmias is not required. The pericardial space has also been used to deliver therapy for several cardiac diseases. There are reports on successful delivery of drugs and their efficacy. Even though there was a wide range of efficacies reported in those studies, the reported complication rates are strikingly low, which suggests that direct delivery of drugs to the epicardium via the pericardial space is safe. Furthermore, recent animal studies have supported the feasibility of epicardial delivery of biological agents, including genes, cells, and even genetically engineered tissue for therapeutic purposes. In conclusion, percutaneous pericardial cannulation of closed pericardial space can play a significant role in providing non-surgical therapy for cardiovascular diseases. However, it requires skills and operator experiences. Therefore, there is need to further develop new tools, safer techniques, and effective procedure environment before generalizing this procedure.
Animals ; Arrhythmias, Cardiac ; Biological Agents ; Cardiovascular Diseases ; Catheterization ; Catheters ; Drug Administration Routes ; Heart Diseases ; Humans ; Pericardium ; Thoracic Surgery ; Thoracotomy

The efficacy and safety of catheter ablation for the management of atrial fibrillation (AF) has been improved in recent years. Radiofrequency (RF) catheter ablation for maintaining sinus rhythm is superior to the current antiarrhythmic drug therapy in selected patients. Pulmonary vein isolation (PVI) is the cornerstone of various catheter ablation strategies. It is well recognized that pulmonary vein (PV) antrum contributes to the AF initiation and/or perpetuation. Since PV stenosis is a complication of ablation within a PV, the ablation site for PVI has shifted to the junction between the left atrium and the PV rather than the ostium of the PV. However, PV reconnection after ablation is the major cause of recurrence of AF. The recovery of PV conduction could be caused by anatomical variations such as the failure to produce complete transmural lesion or gaps at the ablation line due to the transient electrophysiologic effects from the RF ablation. In this review, we discussed several factors to be considered for the achievement of the best PVI, including clinical aspects and technical aspects.
Atrial Fibrillation ; Catheter Ablation ; Constriction, Pathologic ; Drug Therapy ; Heart Atria ; Humans ; Pulmonary Veins* ; Recurrence

BACKGROUND: Although it is well known that bone mineral density (BMD) loss occurs after menopausal transition, there are only few previous studies that describe differences of BMD and biochemical bone markers in women of pre- and postmenopausal periods. The purpose of this study was to find factors that contribute to loss of BMD after menopause and to show changes of BMD and biochemical bone markers during pre- and postmenopausal periods by retrospective cohort study. METHODS: This retrospective cohort study was performed from Jan. 1995 to Jan. 2001 at a health promotion center. Twenty one healthy perimenopausal women were enrolled. BMD and biochemical bone markers were checked more than two times during the study period. Changes of BMD and biochemical bone markers between pre- and postmenopausal state were compared by paired t-test. Pearson correlation and multiple regression were performed to find the contributing factors to loss of BMD after menopause. RESULTS: Postmenopausal BMD (164.65 36.34 mg/cm3) was significantly decreased to 16.49 16.91 mg/cm3 (P<0.001) as compared with premenopausal BMD (181.14 40.81 mg/cm3). In biochemical bone markers only urine deoxypyridinoline had a significant difference (3.30 3.97 nMDP/mMcre, P<0.05) Only premenopausal BMD contributed to decreasing rate of BMD between the two states and the loss of BMD after menopause (P<0.05). CONCLUSION: In perimenopausal healthy women, postmenopausal BMD was significantly decreased as compared with premenopausal BMD. And only premenopausal BMD was shown to be a contributing factor to decreasing rate of BMD between the two states and the loss of BMD after menopause. It suggests that premenopausal BMD is important in predicting postmenopausal osteoporosis and efforts to prevent loss of BMD before menopause can prevent progress of postmenopausal osteoporosis.
Bone Density* ; Cohort Studies* ; Female ; Health Promotion ; Humans ; Menopause ; Osteoporosis, Postmenopausal ; Postmenopause ; Retrospective Studies*

Background: The muscular discontinuities or lack of myocardial extensions around the pulmonary veins (PVs) antrum were previously reported. The objective of our study was to compare the efficacy of a partial antral ablation for PV iso‑ lation (PVI) using ultra-high density (UHD) mapping with a conventional wide antral circumferential ablation (WACA) in atrial fibrillation (AF) patients. Methods: A total of 119 patients medical records who received catheter ablation for AF in our hospital were ana‑ lyzed. In one group of patients, detailed activation mapping of each PV was performed using a UHD mapping system.Each PV antral segment’s activation pattern was classified into “directly-activated from the LA” or “passively-activated from an adjacent PV segment” patterns. The ablation applications were performed at the directly-activated PV antral segment only for the PVI when the PV had “passively-activated segments” (partial antral ablation; PA-UHD group).Another patient group received a conventional WACA for the PVI (WACA group). Results: Sixty patients received partial antral ablation (PA-UHD), and age/sex-matched 59 patients received WACA.In the PA-UHD group, passively-activated segments were observed in 58.3% of all PV segments. The success rate of a partial antral ablation for the PVI in PVs with passively-activated segments was 85%. The 1-year atrial tachyarrhyth‑ mia recurrence did not differ between the PA-UHD and WACA groups. Conclusions Our study revealed the presence of passively-activated PV segments, which could potentially indicate muscular discontinuity at the PV-LA junction. In most PVs with passively-activated segments, PVI was successfully achieved by ablation with only directly-activated segments. The 1-year recurrence rate of atrial tachyarrhythmia in PAUHD group was comparable to that observed in the WACA group.

BACKGROUND: Studies on the efficacy of implantable cardioverter-defibrillator (ICD) therapy for primary prevention in Asian patients are relatively lacking compared to those for secondary prevention. Also, it is important to stratify which patients will benefit from ICD therapy for primary prevention.METHODS: Of 483 consecutive patients who received new implantation of ICD in 9 centers in Korea, 305 patients with reduced left ventricular systolic function and/or documented ventricular fibrillation/tachycardia were enrolled and divided into primary (n = 167) and secondary prevention groups (n = 138).RESULTS: During mean follow-up duration of 2.6 ± 1.6 years, appropriate ICD therapy occurred in 78 patients (25.6%), and appropriate ICD shock and anti-tachycardia pacing occurred in 15.1% and 15.1% of patients, respectively. Appropriate ICD shock rate was not different between the two groups (primary 12% vs. secondary 18.8%, P = 0.118). However, appropriate ICD therapy rate including shock and anti-tachycardia pacing was significantly higher (primary 18% vs. secondary 34.8%, P = 0.001) in the secondary prevention group. Type of prevention and etiology, appropriate and inappropriate ICD shock did not affect all-cause death. High levels of N-terminal pro-B-type natriuretic peptide, New York Heart Association functional class, low levels of estimated glomerular filtration ratio, and body mass index were associated with death before appropriate ICD shock in the primary prevention group. When patients were categorized in 5 risk score groups according to the sum of values defined by each cut-off level, significant differences in death rate before appropriate ICD shock were observed among risk 0 (0%), 1 (3.6%), 2 (3%), 3 (26.5%), and 4 (40%) (P < 0.001).CONCLUSION: In this multicenter regional registry, the frequency of appropriate ICD therapy is not low in the primary prevention group. In addition, combination of poor prognostic factors of heart failure is useful in risk stratification of patients who are not benefiting from ICD therapy for primary prevention.
Asian Continental Ancestry Group ; Body Mass Index ; Defibrillators, Implantable ; Filtration ; Follow-Up Studies ; Heart ; Heart Failure ; Humans ; Korea ; Mortality ; Primary Prevention ; Risk Assessment ; Secondary Prevention ; Shock

Background and Objectives: As the coronavirus disease 2019 (COVID-19) spreads worldwide, cardiac injury in patients infected with COVID-19 becomes a significant concern. Thus, this study investigates the impact of several electrocardiogram (ECG) parameters and disease severity in COVID-19 patients. Methods: Seven medical centers in Daegu admitted 822 patients with COVID-19 between February and April 2020. This study examined 267 patients among them who underwent an ECG test and evaluated their biochemical parameters like C-reactive protein (CRP), log N-terminal pro-B-type Natriuretic Peptide (NT-proBNP), cardiac enzyme, and ECG parameters (heart rate, PR interval, QRS interval, T inversion, QT interval, and Tpe [the interval between peak to end in a T wave]). Results: Those patients were divided into 3 groups of mild (100 patients), moderate (89 patients), and severe (78 patients) according to clinical severity score. The level of CRP, log NT-proBNP, and creatinine kinase-myocardial band were significantly increased in severe patients. Meanwhile, severe patients exhibited prolonged QT intervals (QTc) and Tpe (Tpe-c) compared to mild or moderate patients. Moreover, deceased patients (58; 21.7%) showed increased dispersion of QTc and Tpe-c compared with surviving patients (78.2±41.1 vs. 40.8±24.6 ms and 60.2±37.3 vs. 40.8±24.5 ms, both p<0.05, respectively). The QTc dispersion of more than 56.1 ms could predict the mortality in multivariate analysis (odd ratio, 11.55; 95% confidence interval, 3.746–42.306). Conclusions COVID-19 infections could involve cardiac injuries, especially cardiac repolarization abnormalities. A prolonged QTc dispersion could be an independent predictable factor of mortality.

Background and Objectives: As the coronavirus disease 2019 (COVID-19) spreads worldwide, cardiac injury in patients infected with COVID-19 becomes a significant concern. Thus, this study investigates the impact of several electrocardiogram (ECG) parameters and disease severity in COVID-19 patients. Methods: Seven medical centers in Daegu admitted 822 patients with COVID-19 between February and April 2020. This study examined 267 patients among them who underwent an ECG test and evaluated their biochemical parameters like C-reactive protein (CRP), log N-terminal pro-B-type Natriuretic Peptide (NT-proBNP), cardiac enzyme, and ECG parameters (heart rate, PR interval, QRS interval, T inversion, QT interval, and Tpe [the interval between peak to end in a T wave]). Results: Those patients were divided into 3 groups of mild (100 patients), moderate (89 patients), and severe (78 patients) according to clinical severity score. The level of CRP, log NT-proBNP, and creatinine kinase-myocardial band were significantly increased in severe patients. Meanwhile, severe patients exhibited prolonged QT intervals (QTc) and Tpe (Tpe-c) compared to mild or moderate patients. Moreover, deceased patients (58; 21.7%) showed increased dispersion of QTc and Tpe-c compared with surviving patients (78.2±41.1 vs. 40.8±24.6 ms and 60.2±37.3 vs. 40.8±24.5 ms, both p<0.05, respectively). The QTc dispersion of more than 56.1 ms could predict the mortality in multivariate analysis (odd ratio, 11.55; 95% confidence interval, 3.746–42.306). Conclusions COVID-19 infections could involve cardiac injuries, especially cardiac repolarization abnormalities. A prolonged QTc dispersion could be an independent predictable factor of mortality.

Background: Implantable loop recorders (ILRs) can provide an enhanced possibility to detect atrial fibrillation (AF), but the accuracy, especially the positive predictive value (PPV), is controversial. This study aimed to evaluate the accuracy of ILRs for detecting AF through a comparison with Holter. Method and results: Thirteen patients who underwent AF ablation were enrolled. ILRs were implanted in all patients, who were scheduled to have Holter monitorings after the procedure. The incidence of AF was compared between the two modalities and analyzed for any correlations. A total of 51 Holters (67,985.5 min) and concomitant ILRs were available for the comparison. The judgment of the presence of AF did not perfectly correlate between the ILR and Holter (Kappa = 0.866, P < 0.001). In the ILR data, the sensitivity of detecting AF on the Holter was 81.6% (95% confidence interval [CI] 0.812–0.820; P < 0.001). The specificity was 99.9% (95% CI 0.998–0.999; P < 0.001). When the ILR detected AF, the PPV was 99.5% (95% CI 0.994–0.995), but the ILR did not detect AF, and the negative predictive value was 94.2% (95% CI 0.941–0.944). A separate analysis of AF/atrial tachycardia (AT) showed that the AT detection rate of the ILR was 2.3%. Conclusion The ILR had a low false positive value and high PPV for AF events. However, it was limited in identifying AT.

Background: Carvedilol is one of the most effective beta-blockers in reducing ventricular tachyarrhythmias and mortality in patients with heart failure. One of the possible antiarrhythmic mechanisms of carvedilol is the suppression of store overload-induced Ca2+ release, especially for the triggered activity. Objectives: Premature ventricular complex (PVC) originating from the ventricular outflow tract (OT) is the most common form of idiopathic PVC, and its main mechanism is related to triggered activity. We evaluate the efficacy of carvedilol to suppress the OT PVC. Methods: The electronic medical records at our hospital were screened to identify OT PVC patients treated with carvedilol. Clinical, electrocardiographic, and Holter monitoring studies were reviewed. Results: A total of 25 patients who underwent Holter monitoring before and after carvedilol administration were found and enrolled. The mean age of the patients was 54.9 ± 13.9 years, and the mean dose of carvedilol was 18.2 ± 10.2 mg (sustained release formulation, 8/16/32 mg). The 24-h burden of PVC in 18 (72%) of 25 patients was significantly reduced from 12.2 ± 9.7% to 4.4 ± 6.7% (P = 0.006). In seven patients, the burden of PVC was changed from 7.1 ± 6.1% to 9.8 ± 8.4% (P = 0.061). There was no difference in age, carvedilol dose, duration of treatment, ventricular function, and left atrial size between responding and non-responding groups. Conclusion In this retrospective pilot study, treatment with carvedilol showed PVC suppression in 72% of patients. Now, we are conducting a prospective, randomized, multicenter study to evaluate the effect of carvedilol on OT PVC (Clinical trial registration: FOREVER trial, Clinical-Trials.gov: NCT03587558).

BACKGROUND: Studies on the efficacy of implantable cardioverter-defibrillator (ICD) therapy for primary prevention in Asian patients are relatively lacking compared to those for secondary prevention. Also, it is important to stratify which patients will benefit from ICD therapy for primary prevention. METHODS: Of 483 consecutive patients who received new implantation of ICD in 9 centers in Korea, 305 patients with reduced left ventricular systolic function and/or documented ventricular fibrillation/tachycardia were enrolled and divided into primary (n = 167) and secondary prevention groups (n = 138). RESULTS: During mean follow-up duration of 2.6 ± 1.6 years, appropriate ICD therapy occurred in 78 patients (25.6%), and appropriate ICD shock and anti-tachycardia pacing occurred in 15.1% and 15.1% of patients, respectively. Appropriate ICD shock rate was not different between the two groups (primary 12% vs. secondary 18.8%, P = 0.118). However, appropriate ICD therapy rate including shock and anti-tachycardia pacing was significantly higher (primary 18% vs. secondary 34.8%, P = 0.001) in the secondary prevention group. Type of prevention and etiology, appropriate and inappropriate ICD shock did not affect all-cause death. High levels of N-terminal pro-B-type natriuretic peptide, New York Heart Association functional class, low levels of estimated glomerular filtration ratio, and body mass index were associated with death before appropriate ICD shock in the primary prevention group. When patients were categorized in 5 risk score groups according to the sum of values defined by each cut-off level, significant differences in death rate before appropriate ICD shock were observed among risk 0 (0%), 1 (3.6%), 2 (3%), 3 (26.5%), and 4 (40%) (P < 0.001). CONCLUSION In this multicenter regional registry, the frequency of appropriate ICD therapy is not low in the primary prevention group. In addition, combination of poor prognostic factors of heart failure is useful in risk stratification of patients who are not benefiting from ICD therapy for primary prevention.