Heart Failure ; prevention & control ; Humans ; Mitochondria

Heart Failure, Diastolic ; diagnosis ; prevention & control ; Humans

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.
Death, Sudden, Cardiac ; Defibrillators, Implantable* ; Follow-Up Studies ; Heart Failure ; Humans ; Korea* ; Primary Prevention ; Prognosis* ; Secondary Prevention

Chronic heart failure(CHF) has become a worldwide public health problem due to its high morbidity and mortality, which seriously endangers people's lifespan and quality of life. In recent years, the treatment strategy of CHF has shifted its emphasis on short-term improvement and transformation of hemodynamics to long-term repair as well as improvement of the biological properties of heart failure. At present, with the continuous deepening of medical research, it has been found that histone acetylation is closely related to the occurrence and development of CHF. Traditional Chinese medicine, via regulating histone acetylation, delays ventricular remodeling, improves energy metabolism, inhibits fibrosis and cardiomyocyte hypertrophy, and intervenes in the development process of heart failure, thus reducing the mortality and the readmission rate and ultimately improving long-term prognosis. Therefore, this study reviewed the mechanism of histone acetylation in the treatment of heart failure as well as its prevention and treatment with traditional Chinese medicine, to provide reference for clinical treatment of CHF.
Humans ; Medicine, Chinese Traditional ; Histones/therapeutic use* ; Acetylation ; Quality of Life ; Heart Failure/prevention & control*

The use of an implantable cardioverter-defibrillator (ICD) is an effective treatment strategy for patients with aborted sudden cardiac death (SCD) and ventricular tachyarrhythmias. Primary prevention of SCD is a strategy involving the use of ICDs in patients who are at high risk for but who have not had any previous events of ventricular arrhythmias or cardiac arrest. Cardiac resynchronization therapy (CRT) improves symptoms of heart failure and left ventricular systolic function when used in patients with severe heart failure symptoms, reduced left ventricular ejection, and a wide QRS complex. CRT has also been proven to reduce the rate of hospitalization due to heart failure as well as the rate of death from any cause. In this review, we discuss the clinical trials and current clinical indications for the ICD and CRT.
Arrhythmias, Cardiac ; Cardiac Resynchronization Therapy* ; Death, Sudden, Cardiac ; Defibrillators, Implantable* ; Heart Arrest ; Heart Failure ; Hospitalization ; Humans ; Primary Prevention ; Tachycardia

BACKGROUND AND OBJECTIVES: This study was performed to describe clinical characteristics of patients with left ventriculars (LV) dysfunction and implantable cardioverter-defibrillator (ICD), and to evaluate the effect of ICD therapy on survival in Yeongnam province of Korea. SUBJECTS AND METHODS: From a community-based device registry (9 centers, Yeongnam province, from November 1999 to September 2012), 146 patients with LV dysfunction and an ICD implanted for primary or secondary prophylaxis, were analyzed. The patients were divided into two groups, based on the etiology (73 with ischemic cardiomyopathy and 73 with non-ischemic cardiomyopathy), and indication for the device implantation (36 for primary prevention and 110 for secondary prevention). The cumulative first shock rate, all cause death, and type and mode of death, were determined according to the etiology and indication. RESULTS: Over a mean follow-up of 3.5 years, the overall ICD shock rate was about 39.0%. ICD shock therapy was significantly more frequent in the secondary prevention group (46.4% vs. 16.7%, p=0.002). The cumulative probability of a first appropriate shock was higher in the secondary prevention group (p=0.015). There was no significant difference in the all-cause death, cardiac death, and mode of death between the groups according to the etiology and indication. CONCLUSION: Studies from this multicenter regional registry data shows that in both ischemic and non-ischemic cardiomyopathy patients, the ICD shock therapy rate was higher in the secondary prevention group than primary prevention group.
Cardiomyopathies ; Convulsive Therapy ; Death ; Defibrillators, Implantable* ; Follow-Up Studies ; Heart Failure* ; Heart* ; Humans ; Korea* ; Mortality ; Primary Prevention ; Secondary Prevention ; Shock ; Ventricular Dysfunction, Left

The tip structure is one of the key factors to determine the performance of left ventricular assist device (LVAD) inflow cannulas. The tip structure influences the thrombosis, hemolysis in cannula and left ventricle and suction leading to obstruction in ventricle. We designed four kinds of inflow cannulas that had different tips and built the numerical models of the four historical used inflow cannulas inserted into the apex of left ventricle. We computed the hemodynamic characteristics of inflow cannulas insertion by Fluent software. We researched the backflow, turbulent flow and pressure distribution of the four inflow cannulas. The results showed that the trumpet tipped inflow cannula had smooth flow velocity distribution without backflow or low velocity flow. The trumpet tipped inflow cannula had the best blood compatibility characteristics. The trumpet structure could prevent obstruction. The caged tipped cannula had serious turbulent flow which could possibly cause thrombosis and the low pressure near left ventricle wall and easily lead to ventricle collapse. The trumpet tipped inflow cannula has the best blood compatibility and is difficult to be obstructed. The trumpet tipped inflow cannula is fit to long-term use LVAD.
Catheters ; Computer Simulation ; Equipment Design ; Heart Failure ; therapy ; Heart-Assist Devices ; adverse effects ; Hemolysis ; Humans ; Numerical Analysis, Computer-Assisted ; Thrombosis ; prevention & control ; Ventricular Dysfunction, Left ; prevention & control

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

OBJECTIVETo investigate whether Tpeak-Tend interval (Tp-e) and Tp-e/QT ratio are associated with malignant ventricular arrhythmia in patients with implantable cardioverter-defibrillator (ICD) for primary prevention.

METHODSA cohort of 68 consecutive patients with chronic heart failure undergoing standard ICD for primary prevention indications (NYHA function class II-III, left ventricular ejection fraction ≤35%, systolic cardiomyopathy without prior malignant ventricular arrhythmia) were enrolled in this study. The patients were followed up for 18-48 months and were divided into high-risk group and low-risk group according to the occurrence of the endpoint events of sudden cardiac death (SCD), ventricular tachycardia (VT), or ventricular fibrillation (VF). Electrocardiographic and echocardiographic characteristics, Tp-e, and Tp-e/QT ratio were analyzed in all cases before ICD implantation.

RESULTSDuring the follow-up, ICD shock for sustained ventricular tachycardia or ventricular fibrillation occurred in 11 patients; nonsustained ventricular tachycardia (NSVT) that did not require therapy was detected by ICD in 7 patients (high-risk group, 18 cases). ICD did not detect ventricular tachycardia or ventricular fibrillation in 50 patients (low-rsk group). Compared with the low-rsik group, the high-risk group had an increased Tp-e/QT ratio (0.27±0.04 vs 0.22±0.05 P<0.01) and an increased Tp-e (105±15 vs 90±17 ms P<0.01). ROC analysis revealed that a Tp-e/QT ratio ≥0.255 had a sensitivity of 72.2% and a specificity of 65.9%, and a Tp-e ≥103 ms had a sensitivity of 66.7% and a specificity of 67.9% for predicting VT and VF in these patients.

CONCLUSIONIncreased Tp-e and Tp-e/QT ratio are associated with increased risks of ventricular arrhythmias in patients with ICD for primary prevention.

Death, Sudden, Cardiac ; prevention & control ; Defibrillators, Implantable ; Electrocardiography ; Heart Failure ; therapy ; Humans ; Primary Prevention ; ROC Curve ; Tachycardia, Ventricular ; prevention & control ; Ventricular Fibrillation ; Ventricular Function, Left

BACKGROUNDP-wave dispersion (PWD) is a useful predictor of paroxysmal atrial fibrillation (AF). The effect of cardiac resynchronization therapy (CRT) on PWD and the prognostic implications of the improvement in PWD remain undefined. The aim of the study was to explore the clinical significance of the improvement of PWD after CRT.

METHODSElectrocardiographic studies were performed before and three months after CRT in 81 patients (57 men and 24 women; age (60.5 ± 11.2) years) with standard CRT indication but no history of AF. A significant improvement of PWD (PWD responder) was defined as a relative decrease ≥ 20% from baseline PWD. The primary endpoints were new-onset AF detected by electrocardiogram (ECG) or CRT.

RESULTSAfter (30.6 ± 7.5) months of follow-up, PWD responders (n = 43) had a significantly lower incidence of AF than did PWD nonresponders, 12% vs. 29% (P < 0.001). In Cox proportional hazard analysis, PWD responders was the only predictor of lower risk of new-onset AF (HR 0.33, 95% confidence interval 0.12 - 0.96, P = 0.033).

CONCLUSIONImprovement of P-wave dispersion after CRT was associated with a lower incidence of AF, which may be related to the significant improvement in left ventricular systolic function and the reverse modeling of the left atrium.

Adult ; Aged ; Atrial Fibrillation ; prevention & control ; Cardiac Resynchronization Therapy ; Echocardiography ; Electrocardiography ; Female ; Heart Failure ; physiopathology ; therapy ; Humans ; Male ; Middle Aged