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Pulmonary vein isolation is an well-established treatment strategy for atrial fibrillation (AF), and it is especially effective for patients with paroxysmal AF. However, the success rate is limited for patients with persistent AF, because non-pul‑ monary vein triggers which increase AF recurrence are frequently found in these patients. The major non-pulmonary vein triggers are from the left atrial posterior wall, left atrial appendage, ligament of Marshall, coronary sinus, superior vena cava, and crista terminalis, but other atrial sites can also generate AF triggers. All these sites have been known to contain atrial myocytes with potential arrhythmogenic electrical activity. The prevalence and clinical characteristics of these non-pulmonary vein triggers are well studied; however, the clinical outcome of catheter ablation for persistent AF is still unclear. Here, we reviewed the current ablation strategies for persistent AF and the clinical implications of major non-pulmonary vein triggers.
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Background and Objectives@#Atrial tachycardias (ATs) from noncoronary aortic cusp (NCC) uncovered after radiofrequency ablation for atrial fibrillation (AF) are rarely reported. This study was conducted to investigate the prevalence and clinical characteristics of NCC ATs detected during AF ablation and compare their characteristics with de novo NCC ATs without AF. @*Methods@#Consecutive patients who underwent radiofrequency catheter ablation for AF were reviewed from the multicenter AF ablation registry of 11 tertiary hospitals. The clinical and electrophysiological characteristics of NCC AT newly detected during AF ablation were compared with its comparators (de novo NCC AT ablation cases without AF). @*Results@#Among 10,178 AF cases, including 1,301 redo ablation cases, 8 (0.08%) NCC AT cases were discovered after pulmonary vein isolation (PVI; 0.07% in first ablation and 0.15% in redo ablation cases). All ATs were reproducibly inducible spontaneously or with programmed atrial stimulation without isoproterenol infusion. The P-wave morphological features of tachycardia were variable depending on the case, and most cases exhibited 1:1 atrioventricular conduction. AF recurrence rate after PVI and NCC AT successful ablation was 12.5% (1 of 8). Tachycardia cycle length was shorter than that of 17 de novo ATs from NCC (303 versus 378, p=0.012). No AV block occurred during and after successful AT ablation. @*Conclusions@#Uncommon NCC ATs (0.08% in AF ablation cases) uncovered after PVI, showing different characteristics compared to de-novo NCC ATs, should be suspected irrespective of P-wave morphologies when AT shows broad propagation from the anterior interatrial septum.
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Background@#The major cause of recurrence after pulmonary vein (PV) isolation for atrial fibrillation (AF) is PV recon‑ nection, and thicker wall could be associated with reconnection. @*Objectives@#This study aimed to evaluate the wall thickness of the PV antrum in reconnection sites using a threedimensional (3D) wall thickness map. @*Methods@#A total of 91 patients who underwent a second ablation procedure due to AF recurrence were evalu‑ ated. The locations of the PV reconnection sites were confirmed in electroanatomical maps. A 3D atrial wall thickness (AWT) map was created using computed tomography scan data. The AWT values of the ablation lines of the index procedure were graded in each segment of the PV antrum: grade 1, 0.5 2.5 mm. @*Results@#A total of 281 PV reconnection sites among 1256 segments of the PV antrum in 79 patients were detected. The average AWT grades were 2.7 ± 1.0 and 2.2 ± 1.0 in the reconnected and non-reconnected segments, respectively (P < 0.01). Higher AWT grades were observed in the reconnected superior segments of the left superior PV, carina and inferior segments of the left inferior PV, superior and posterior segments of the right superior PV, and posterior and inferior segments of the right inferior PV. @*Conclusion@#The reconnected segments of the PV antrum showed thicker myocardium than the non-reconnected ones in patients with recurrent AF after catheter ablation. A wall thickness map for PV isolation could be considered for customized ablation in order to reduce PV reconnection.
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Purpose@#To provide a new insight on a novel safe cardiac radioablation using deep inspiration breath-hold (DIBH) to reduce gastrointestinal dose. @*Materials and Methods@#For treating incessant ventricular tachycardia (VT) originated from left ventricle inferior scar abutting the stomach, a target delineation and treatment planning for cardiac radioablation was performed. With four different computed tomography (CT) scan protocols—DIBH, full expiration breath-hold, four-dimensional (4D) CT without and with abdominal compression, the distances between the target and the stomach were compared. @*Results@#Among the protocols, the CT scan with DIBH showed largest distance between the target and the stomach and selected for the treatment planning. The prescribed dose was 25 Gy in a single fraction, and satisfactory dosimetric parameters were achieved with the DIBH. The patient was successfully treated with the DIBH, and experienced no acute toxicity. @*Conclusion@#To gain the best benefit from cardiac radioablation, understanding the possible toxicity in the adjacent organs is crucial. By moving the heart with thoraco-diaphragmatic movement by DIBH, the target could be physically separated from the stomach.
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Background/Aims@#Comparative occurrence of ischemic stroke for rhythm versus rate control strategy in patients with non-valvular atrial fibrillation (NVAF) is still inconclusive. The purpose of this study was to investigate whether the rhythm control strategy is associated with a lower risk of ischemic stroke compared to the rate control strategy in NVAF patients. @*Methods@#The CODE-AF registry prospectively enrolled 6,280 consecutive patients who were treated for NVAF at 10 tertiary referral centers in South Korea. Of these, 2,513 NVAF patients (age, 67 ± 10 years; male, 61.8%) were clinically followed up for over 1-year and divided into rate and rhythm control groups. @*Results@#Those treated with the rhythm control strategy were younger and had less proportions of underlying disease compared to those treated with the rate control strategy. After the propensity matching analysis, those treated with the rhythm control strategy had similar baseline characteristics including the CHA 2 DS 2 -VASC score compared to those treated with the rate control strategy.The rate of oral anticoagulation, all bleeding, and hospitalization were also similarly between the two groups. The incidence rate of ischemic stroke in the rhythm control group was significantly lower than in the rate control group (0.7 vs. 6.9 per 1,000 person-years, p = 0.011). @*Conclusions@#The rhythm control strategy demonstrated a beneficial effect to lower the risk of ischemic stroke during a 1-year follow-up compared to the rate control strategy.
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The prevalence of atrial fibrillation (AF) is gradually increasing with the aging of the population, and there is also increasing interest in AF with the development of various single-lead electrocardiography measurement methods for diagnosis. Further, the current diagnosis and treatment policies for AF do not reflect its progression and complexity. In addition, the various factors related to AF diagnosis and treatment are not simple due to the diversification of tools, advances in treatment methods, and complex mechanism of AF. Therefore, there are many challenges to developing a simple AF classification system. To overcome these, there have been a number of attempts to systematically characterize AF according to treatment and prognosis rather than using a uniform classification. Further, as mentioned in the previous AF guidelines, further research is being conducted on an integrated patient–physician approach to AF. Such an approach would be the basis for consistent treatment based on the guidelines, and would help to improve patient outcomes. Further, for the integrated management of AF patients, some changes should be made to the current approach to develop a multidisciplinary approach, including changes to the behavior of team members, patients, their family members, and physicians. The Korean Heart Rhythm will introduce an integrated approach to the classification and structure of AF management, and provide guidelines for its application in clinical practice.
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Purpose@#To provide a new insight on a novel safe cardiac radioablation using deep inspiration breath-hold (DIBH) to reduce gastrointestinal dose. @*Materials and Methods@#For treating incessant ventricular tachycardia (VT) originated from left ventricle inferior scar abutting the stomach, a target delineation and treatment planning for cardiac radioablation was performed. With four different computed tomography (CT) scan protocols—DIBH, full expiration breath-hold, four-dimensional (4D) CT without and with abdominal compression, the distances between the target and the stomach were compared. @*Results@#Among the protocols, the CT scan with DIBH showed largest distance between the target and the stomach and selected for the treatment planning. The prescribed dose was 25 Gy in a single fraction, and satisfactory dosimetric parameters were achieved with the DIBH. The patient was successfully treated with the DIBH, and experienced no acute toxicity. @*Conclusion@#To gain the best benefit from cardiac radioablation, understanding the possible toxicity in the adjacent organs is crucial. By moving the heart with thoraco-diaphragmatic movement by DIBH, the target could be physically separated from the stomach.
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Subject(s)
Female , Humans , Male , Anticoagulants , Atrial Fibrillation , Heart Valve Diseases , Hemorrhage , Kidney Failure, Chronic , Multivariate Analysis , Myocardial Infarction , Platelet Aggregation Inhibitors , Prospective Studies , Smoke , Smoking , Stroke , WarfarinABSTRACT
Background@#In patients with atrial fibrillation (AF), most biomarkers are still of limited use due to cost-effectiveness and complexity in clinical practice.Hypotheses Biomarkers from routine blood tests improve the current risk stratification in AF patients. @*Methods@#This prospective study enrolled 600 patients diagnosed with non-valvular AF, of whom 537 were analyzed. Platelet count; platelet distribution width (PDW); red cell distribution width (RDW); and creatinine, D-dimer, and troponin I levels were measured at enrollment. @*Results@#During the mean follow-up period (2.2 ± 0.6 years), 1.9% patients developed ischemic stroke. According to the optimal cutoff of each biomarker, the risk of ischemic stroke was higher in patients with RDW ≥ 13.5%, creatinine ≥ 1.11 mg/dL, or PDW ≥ 13.2% (significant biomarkers; P value: < 0.01, 0.04, or 0.07, respectively). These 3 significant biomarkers had higher information gain than clinical risk factors in predicting ischemic stroke. The cumulative incidence of ischemic stroke was 1.2%, 1.1%, 8.4%, and 40.0% in patients with 0, 1, 2, and 3 significant biomarkers, respectively (P-for-trend < 0.001). Patients with ≥ 2 significant biomarkers had a significantly higher risk of ischemic stroke than those with < 2 significant biomarkers (adjusted hazard ratio 11.5, 95% confidence interval 3.3–40.2, P < 0.001). The predictability for ischemic stroke was significantly improved when ≥ 2 significant biomarkers were added to the CHA2DS2–VASc score (area under the curve 0.790 vs. 0.620, P = 0.043). @*Conclusion@#Routine blood tests can provide better risk stratification of AF along with clinical risk factors.
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Background@#Symptom burden is an important factor in determining the treatment of atrial fibrillation (AF). AF is frequently accompanied by heart failure (HF). This study investigated the characteristics of AF symptoms with concomitant HF. @*Methods@#A total of 4885 patients with AF were consecutively enrolled through a prospective observational registry (the Comparison Study of Drugs for Symptom Control and Complication Prevention of Atrial Fibrillation [CODE-AF] registry). Clinically diagnosed HF was divided into three categories (preserved, mid-range, and reduced ejection fraction [EF]). Symptom severity was assessed using the European Heart Rhythm Association (EHRA) classification. @*Results@#The presence of AF-related symptoms was comparable irrespective of concomitant HF. Patients with HF with reduced EF demonstrated severe (EHRA classes 3 and 4) and atypical symptoms. HF with preserved EF was also associated with atypical symptoms. Female sex and AF type were associated with the presence of symptoms in AF without HF, and non-maintenance of sinus rhythm and increased left atrial pressure (E/e′ ≥ 15) were factors related to the presence of symptoms in AF with HF. @*Conclusion@#AF with concomitant HF presented with more severe and atypical symptoms than AF without HF. Maintaining the sinus rhythm and reducing the E/e’ ratio are important factors for reducing symptoms in AF with concomitant HF.
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Purpose@#Dose reduction of non-vitamin K antagonist oral anticoagulants (NOACs) is indicated in patients with atrial fibrillation (AF) with renal impairment. This study investigated anticoagulation patterns and outcomes in patients with chronic kidney disease (CKD). @*Materials and methods@#In a prospective observational registry (CODE-AF), 3445 patients with non-valvular AF including 1129 with CKD (estimated glomerular filtration rate ≤ 60 mL min−1 1.73 m−2) were identified between June 1, 2016, and July 3, 2017. @*Results@#Compared with patients with no-CKD, patients with CKD more frequently had a high stroke risk (94.9% vs. 67.0%, p < 0.001) and higher NOAC usage rate (61.1% vs. 47.8%, p < 0.001). Among 718 patients with renal indication for dose reduction (RIDR), 7.5% were potentially overdosed. Among 2587 patients with no-RIDR, 79% were potentially underdosed. Compared with patients with no-RIDR, the underdose rates of dabigatran (0% vs. 88.6%, p = 0.001) and rivaroxaban (0% vs. 79.5%, p = 0.001) were lower in patients with RIDR. However, the underdose rate of apixaban was not different (62.5% vs. 53.9%, p = 0.089). The overdose rate of dabigatran (7.5% vs. 0%) and rivaroxaban (13.7% vs. 0%) was higher in RIDR than in no-RIDR patients. Stroke/transient ischemic attack was significantly higher in CKD patients (1.4 vs. 0.6 per 100 person-years, p = 0.045). Aspirin significantly increased minor bleeding in CKD patients compared with controls (p = 0.037). @*Conclusion@#CKD patients might have a high stroke risk and NOAC usage rate. The underdose rate of NOACs decreased in CKD patients, except for apixaban. Aspirin significantly increased minor bleeding in CKD patients.
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Background@#The definitive pathologic diagnosis of cardiac sarcoidosis requires observation of a granuloma in the myocardial tissue. It is common, however, to receive a “negative” report for a clinically probable case. We would like to advise pathologists and clinicians on how to interpret “negative” biopsies. @*Methods@#Our study samples were 27 endomyocardial biopsies from 25 patients, three cardiac transplantation and an autopsied heart with suspected cardiac sarcoidosis. Pathologic, radiologic, and clinical features were compared. @*Results@#The presence of micro-granulomas or increased histiocytic infiltration was always (6/6 or 100%) associated with fatty infiltration and confluent fibrosis, and they showed radiological features of sarcoidosis. Three of five cases (60%) with fatty change and confluent fibrosis were probable for cardiac sarcoidosis on radiology. When either confluent fibrosis or fatty change was present, one-third (3/9) were radiologically probable for cardiac sarcoidosis. We interpreted cases with micro-granuloma as positive for cardiac sarcoidosis (five of 25, 20%). Cases with both confluent fibrosis and fatty change were interpreted as probable for cardiac sarcoidosis (seven of 25, 28%). Another 13 cases, including eight cases with either confluent fibrosis or fatty change, were interpreted as low probability based on endomyocardial biopsy. @*Conclusions@#The presence of micro-granuloma could be an evidence for positive diagnosis of cardiac sarcoidosis. Presence of both confluent fibrosis and fatty change is necessary for probable cardiac sarcoidosis in the absence of granuloma. Either of confluent fibrosis or fatty change may be an indirect pathological evidence but they are interpreted as nonspecific findings.
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Background/Aims@#Efforts to reduce stroke in patients with atrial fibrillation (AF) have focused on increasing physician adherence to oral anticoagulant (OAC) guidelines; however, the high early discontinuation rate of vitamin K antagonists (VKAs) is a limitation. Although non-VKA OACs (NOACs) are more convenient to administer than warfarin, their lack of monitoring may predispose patients to nonpersistence. We compared the persistence of NOAC and VKA treatment for AF in real-world practice. @*Methods@#In a prospective observational registry (COmparison study of Drugs for symptom control and complication prEvention of Atrial Fibrillation [CODE-AF] registry), 7,013 patients with nonvalvular AF (mean age 67.2 ± 10.9 years, women 36.4%) were consecutively enrolled between June 2016 and June 2017 from 10 tertiary hospitals in Korea. This study included 3,381 patients who started OAC 30 days before enrollment (maintenance group) and 572 patients who newly started OAC (new-starter group). The persistence rate of OAC was evaluated. @*Results@#In the maintenance group, persistence to OAC declined during 6 months, to 88.3% for VKA and 95.5% for NOAC (p < 0.0001). However, the persistence rate was not different among NOACs. In the new-starter group, persistence to OAC declined during 6 months, to 78.9% for VKA and 92.1% for NOAC (p < 0.0001). The persistence rate was lower for rivaroxaban (83.7%) than apixaban (94.6%) and edoxaban (94.1%, p < 0.001). In the new-starter group, diabetes, valve disease, and cancer were related to nonpersistence of OAC. @*Conclusions@#Nonpersistence was significantly lower with NOAC than VKA in both the maintenance and new-starter groups. In only the new-starter group, apixaban or edoxaban showed higher persistence rates than rivaroxaban.
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Background@#Although multiple algorithms based on surface electrocardiographic criteria have been introduced to localize idiopathic ventricular arrhythmia (VA) origins from the outflow tract (OT), their diagnostic accuracy and clini‑ cal usefulness remain limited. We evaluated whether local activation time of the His bundle region could differentiate left and right ventricular OT VA origins in the early stage of electrophysiology study. @*Methods@#We studied 30 patients who underwent catheter ablation for OT VAs with a left bundle branch block pat‑ tern and inferior axis QRS morphology. The interval between the local V signal on the mapping catheter placed in the RVOT and His bundle region (V(RVOT)-V(HB) interval) and the interval from QRS complex onset to the local V signal on the His bundle region (QRS-V(HB) interval) were measured during VAs. @*Results@#The V(RVOT)-V(HB) and QRS-V(HB) intervals were significantly shorter in patients with LVOT VAs. The area under the curve (AUC) for the V(RVOT)-V(HB) interval by receiver operating characteristic analysis was 0.865. A cutoff value of ≤ 50 ms predicted an LVOT origin of VA with sensitivity, specificity, and positive and negative predictive values of 100%, 62.5%, 40%, and 100%, respectively. The QRS-V(HB) interval showed similar diagnostic accuracy (AUC, 0.840), and a cutoff value of ≤ 15 ms predicted an LVOT origin of VA with a sensitivity, specificity, and positive and negative predictive values of 100%, 70.8%, 45.2%, and 100%, respectively. @*Conclusion@#The V(RVOT)-V(HB) and QRS-V(HB) intervals could differentiate left from right OT origins of VA with high sensitivity and negative predictive values.
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Background@#Although multiple algorithms based on surface electrocardiographic criteria have been introduced to localize idiopathic ventricular arrhythmia (VA) origins from the outflow tract (OT), their diagnostic accuracy and clini‑ cal usefulness remain limited. We evaluated whether local activation time of the His bundle region could differentiate left and right ventricular OT VA origins in the early stage of electrophysiology study. @*Methods@#We studied 30 patients who underwent catheter ablation for OT VAs with a left bundle branch block pat‑ tern and inferior axis QRS morphology. The interval between the local V signal on the mapping catheter placed in the RVOT and His bundle region (V(RVOT)-V(HB) interval) and the interval from QRS complex onset to the local V signal on the His bundle region (QRS-V(HB) interval) were measured during VAs. @*Results@#The V(RVOT)-V(HB) and QRS-V(HB) intervals were significantly shorter in patients with LVOT VAs. The area under the curve (AUC) for the V(RVOT)-V(HB) interval by receiver operating characteristic analysis was 0.865. A cutoff value of ≤ 50 ms predicted an LVOT origin of VA with sensitivity, specificity, and positive and negative predictive values of 100%, 62.5%, 40%, and 100%, respectively. The QRS-V(HB) interval showed similar diagnostic accuracy (AUC, 0.840), and a cutoff value of ≤ 15 ms predicted an LVOT origin of VA with a sensitivity, specificity, and positive and negative predictive values of 100%, 70.8%, 45.2%, and 100%, respectively. @*Conclusion@#The V(RVOT)-V(HB) and QRS-V(HB) intervals could differentiate left from right OT origins of VA with high sensitivity and negative predictive values.
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Although non-vitamin K-antagonist oral anticoagulants (NOACs) reduce major bleeding events in patients with atrial fibrillation more effectively than does warfarin, a significant bleeding risk remains. Patients exhibiting current bleeding and those who are expected to bleed require appropriate management, because NOAC discontinuation may increase the thromboembolic risk. This article details general management principles for patients experiencing current bleeding and those undergoing invasive surgery while on NOACs.
Subject(s)
Humans , Anticoagulants , Atrial Fibrillation , Heart , Hemorrhage , Perioperative Care , WarfarinABSTRACT
PURPOSE: Label adherence for non-vitamin K antagonist oral anticoagulants (NOACs) has not been well evaluated in Asian patients with non-valvular atrial fibrillation (AF). The present study aimed to assess label adherence for NOACs in a Korean AF population and to determine risk factors of off-label prescriptions of NOACs. MATERIALS AND METHODS: In this COmparison study of Drugs for symptom control and complication prEvention of AF (CODE-AF) registry, patients with AF who were prescribed NOACs between June 2016 and May 2017 were included. Four NOAC doses were categorized as on- or off-label use according to Korea Food and Drug Regulations. RESULTS: We evaluated 3080 AF patients treated with NOACs (dabigatran 27.2%, rivaroxaban 23.9%, apixaban 36.9%, and edoxaban 12.0%). The mean age was 70.5±9.2 years; 56.0% were men; and the mean CHA₂DS₂-VASc score was 3.3±1.4. Only one-third of the patients (32.7%) was prescribed a standard dose of NOAC. More than one-third of the study population (n=1122, 36.4%) was prescribed an off-label reduced dose of NOAC. Compared to those with an on-label standard dosing, patients with an off-label reduced dose of NOAC were older (≥75 years), women, and had a lower body weight (≤60 kg), renal dysfunction (creatinine clearance ≤50 mL/min), previous stroke, previous bleeding, hypertension, concomitant dronedarone use, and anti-platelet use. CONCLUSION: In real-world practice, more than one-third of patients with NOAC prescriptions received an off-label reduced dose, which could result in an increased risk of stroke. Considering the high risk of stroke in these patients, on-label use of NOAC is recommended.
Subject(s)
Female , Humans , Male , Anticoagulants , Asian People , Atrial Fibrillation , Body Weight , Cohort Studies , Drug and Narcotic Control , Drug Labeling , Hemorrhage , Hypertension , Korea , Off-Label Use , Prescriptions , Prospective Studies , Risk Factors , Rivaroxaban , StrokeABSTRACT
Although non-vitamin K-antagonist oral anticoagulants (NOACs) reduce major bleeding events in patients with atrial fibrillation more effectively than does warfarin, a significant bleeding risk remains. Patients exhibiting current bleeding and those who are expected to bleed require appropriate management, because NOAC discontinuation may increase the thromboembolic risk. This article details general management principles for patients experiencing current bleeding and those undergoing invasive surgery while on NOACs.
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Syncope is a very common symptom that occurs in all age groups, especially in adolescents and elderly people. The cause of syncope is very diverse, and patients with syncope visit various medical departments such as general medicine, cardiology, neurology, and emergency medicine. If we do not perform appropriate diagnostic tests based on detailed history of syncope, we may have some difficulty to identify the cause of syncope. Failure to identify the cause of syncope can lead to physical trauma due to recurrence of syncope or may increase the risk of cardiovascular events in the future. However, there is no Korean guidelines for the diagnosis and treatment of syncope yet. Considering these circumstances in Korea, we prepared writing and publishing committee for evaluation and management guidelines of syncope in the Korean Society for Holter and Noninvasive Electrocardiology (KSHNE) under the Korean Heart Rhythm Society (KHRS). In this guideline, we reviewed the Korean published literatures and European / American guidelines on syncope.
Subject(s)
Adolescent , Aged , Humans , Cardiology , Diagnosis , Diagnostic Tests, Routine , Emergency Medicine , Heart , Korea , Neurology , Recurrence , Syncope , WritingABSTRACT
The general concept and initial approach to syncope patients has been mentioned in the general sections. This special sections have been described the characteristics, diagnosis, and treatment with patient education for the each syncope. It has been described in order of reflex syncope, orthostatic hypotension, postural orthostatic tachycardia syndrome (POTS), cardiac syncope, and unexplained syncope. Several clinical issues will have been dealt with in special issues. Neurological assessment is added when the patients were diagnosed with psychogenic pseudosyncope (PPS). Although many childhood syncope caused by reflex syncope, they are also presented as syncope caused by arrhythmic events in patients with congenital heart disease. In the elderly patients, syncope is because of not only a single cause of syncope but a combination of various conditions. In case of a syncope patient visiting the emergency department, a standardized systematic approach will be required to determine whether hospitalize the patient according to the risk of recurrence and the needs for the syncope management unit. We also mention recommendations on the limits of driving, exercising and social life style that are relevant to syncope in all patients. In this guideline, we reviewed the Korean published literatures and European/American guidelines on syncope. We, writing and publishing committee for evaluation and management guidelines of syncope in the Korean Society for Holter and Noninvasive Electrocardiography (KSHNE) under the Korean Heart Rhythm Society (KHRS) are very pleased to be able to publish this guideline. We also hope this guideline will be a good support to manage the syncope patients and a useful trigger for further research in Korea.