Dynamic Change of Cardiovascular Health Metrics and Long-Term Risk of Sudden Cardiac Death: The ARIC Study.

Background The change of cardiovascular health (CVH) status has been associated with risk of cardiovascular disease. However, no studies have explored the change patterns of CVH in relation to risk of sudden cardiac death (SCD). We aim to examine the link between baseline CVH and change of CVH over time with the risk of SCD. Methods and Results Analyses were conducted in the prospective cohort ARIC (Atherosclerosis Risk in Communities) study, started in 1987 to 1989. ARIC enrolled 15 792 individuals 45 to 64 years of age from 4 US communities (Forsyth County, North Carolina; Jackson, Mississippi; suburbs of Minneapolis, Minnesota; and Washington County, Maryland). Subjects with 0 to 2, 3 to 4, and 5 to 7 ideal metrics of CVH were categorized as having poor, intermediate, or ideal CVH, respectively. Change in CVH over 6 years between 1987 to 1989 and 1993 to 1995 was considered. The primary study outcome was physician adjudicated SCD. The study population consisted of 15 026 subjects, of whom 12 207 had data about CVH change. Over a median follow-up of 23.0 years, 583 cases of SCD were recorded. There was a strong inverse association between baseline CVH metrics and time varying CVH metrics with risk of SCD. Compared with subjects with consistently poor CVH, risk of SCD was lower in those changed from poor to intermediate/ideal (hazard ratio [HR], 0.67 [95% CI, 0.48-0.94]), intermediate to poor (HR, 0.73 [95% CI, 0.54-0.99]), intermediate to ideal (HR, 0.49 [95% CI, 0.24-0.99]), ideal to poor/intermediate CVH (HR, 0.23 [95% CI, 0.10-0.52]), or those with consistently intermediate (HR, 0.49 [95% CI, 0.36-0.66]) or consistently ideal CVH (HR, 0.31 [95% CI, 0.13-0.76]). Similar results were also observed for non-SCD. Conclusions Compared with consistently poor CVH, other patterns of change in CVH were associated with lower risk of SCD. These findings highlight the importance of promotion of ideal CVH in the primordial prevention of SCD.

Psychological Disturbances and Their Association with Sleep Disturbance in Patients Admitted for Arrhythmia Diseases.

Objectives: This study aimed to assess the depression and anxiety status and their association with sleep disturbance among one single center Chinese inpatients with arrhythmia and help cardiologists better identify patients who need psychological care. Methods: A cross-sectional survey was conducted among 495 inpatients with arrhythmia treated in Fuwai Hospital from October to December 2019. The psychological status and sleep quality were assessed using the Zung Self-Rating Anxiety Scale (SAS), the Zung Self-Rating Depression Scale (SDS) and the Pittsburgh Sleep Quality Index (PSQI). Multivariate logistic regression was used to identify the potential risk factors for anxiety and depression. Results: The mean age of the participants was 52.8 ± 14.4 years, and 58.0% were male. Approximately 18.3% were in an anxious state, and 33.5% were in a depressive state. In multivariate logistic regression, age from 50 to 59 (p = 0.03), unemployment (p = 0.026) and sleep disturbance (p < 0.001) were the risk factors for anxiety status. Cardiac implanted electronic devices (CIEDs) (p = 0.004) and sleep disturbance (p < 0.001) were the risk factors for depression status. A total of 150 patients (30.3%) were categorized as having poor sleep quality (PSQI > 7). The adjusted odds ratio (OR) of having poor sleep quality was 4.30-fold higher in patients with both anxiety and depression (OR: 4.30; 95% confidence interval [CI]: 2.52-7.35); 2.67-fold higher in patients with depression (OR: 2.67; 95% CI: 1.78-4.00); and 3.94-fold higher in patients with anxiety (OR: 3.94; 95% CI: 2.41-6.44). Conclusions: Psychological intervention is critical for Chinese inpatients with arrhythmia, especially for patients aged 50-59, unemployed, or those using CIEDs. Poor sleep quality could be an important risk factor linked to psychological disturbances.

Spatial Distribution of Idiopathic Ventricular Arrhythmias Originating Around the Pulmonary Root: Lessons From Intracardiac Echocardiography.

OBJECTIVES: The purpose of this study was to investigate the spatial distribution of ventricular arrhythmias (VAs) and their relationship with anatomic landmarks in the right ventricular outflow tract (RVOT). BACKGROUND: Although controversy has mainly focused on whether VAs ablated in the RVOT originate above or below the pulmonary sinus, little is known about their actual distribution. METHODS: We performed mapping and ablation in the reconstructed RVOT using intracardiac echocardiography (ICE) and summarized the spatial electroanatomic characteristics of RVOT-VAs. RESULTS: A total of 50 VAs were recruited and were distributed among the 3 subregions: the pulmonary sinuses (19 of 50, 38%), sinus junctions (18 of 50, 36%), and infundibulum (13 of 50, 26%). In total, 70% (35 of 50) of ablation targets were within 10 mm (mean 4.3 ± 2.7 mm) of the pulmonary valve hinge point. An ablation target with both amplitude ≤1.14 mV and duration ≥101.5 milliseconds predicted an origin above the pulmonary sinus with a sensitivity of 84.2% and specificity of 84.4%. For the ablation targets (13 of 50, 26%) located in the infundibulum of the RVOT, 4 were surrounded by trabeculations, whereas only 1 ablation target in the sinus junction abutted the trabeculation (30.8% vs 5.6%). CONCLUSIONS: Ablation targets of RVOT-VAs were mainly distributed around the hinge point of the pulmonary valve and the trabeculation of the infundibulum. ICE can clearly and precisely locate those anatomic landmarks of the RVOT.

Mitral Regurgitation and Body Mass Index Increase the Predictability of Perioperative Bleeding in Anticoagulated Patients With Nonvalvular Atrial Fibrillation.

Background: Catheter ablation (CA) effectively restores sinus rhythm in atrial fibrillation (AF) but causes a short-term fluctuation in the coagulation state. Potential risk factors and better management during this perioperative period remain understudied. Methods: We consecutively included 940 patients with nonvalvular AF who received CA at Fuwai Hospital, Beijing, China. Patients were divided into two groups according to their bleeding status during 3 months' anticoagulation. Any adverse events related to bleeding in the 3 months were evaluated. The HAS-BLED score and ABC-bleeding score, as well as other potential factors, were explored to predict bleeding risk. Results: In this observational study, 8.0% and 0.9% of the whole population suffered from bleeding and thromboembolic events, respectively. After adjusting for known factors related to bleeding, mitral regurgitation (MR, p for trend <0.001) and body mass index (BMI, odds ratio (OR) = 0.920, 95% CI 0.852-0.993, p = 0.033) were the most significant ones. C-indexes of the HAS-BLED score and ABC-bleeding score for bleeding were 0.558 (0.492-0.624) and 0.585 (0.515-0.655), respectively. The incorporation of MR and BMI significantly improved the predictive value based on HAS-BLED score (C-index = 0.650, 95% CI 0.585-0.715, p = 0.004) and ABC-bleeding score (C-index = 0.671, 95% CI 0.611-0.731, p < 0.001). The relative risk of mild-moderate MR was 4.500 (95% CI 1.625-12.460) in patients with AF having HAS-BLED = 1 and 4.654 (95% CI 1.496-14.475) in HAS-BLED ≥ 2, while it was not observed in patients with HAS-BLED = 0 (p = 0.722). Conclusion: More severe MR and lower BMI are associated with a higher incidence of perioperative bleeding, which helps improve the predictability of increased individual bleeding risk of a patient with nonvalvular AF who has received CA therapy and oral anticoagulants.

Catheter ablation of premature ventricular complexes associated with left ventricular false tendons.

BACKGROUND: Clinical studies have suggested that there is a significant correlation between left ventricular (LV) false tendon and premature ventricular complexes (PVCs). OBJECTIVE: This study aimed to investigate the electrophysiological characteristics and the outcome of radiofrequency catheter ablation (RFCA) for this category of PVCs. METHODS: From a total of 2284 patients with idiopathic PVCs who underwent catheter ablation at 6 institutions in China, intracardiac echocardiography (ICE) was used during the procedure in 346 cases; 10 patients (2.9%) with PVCs associated with false tendon were retrospectively reviewed and enrolled in the present study. Activation mapping and pace mapping were performed to localize the origin of PVCs. ICE was used in all patients. If the false tendon was directly visualized and identified, we attempted to identify the distinct relationship with the PVC origin. RESULTS: The PVCs were successfully eliminated by ablation in all patients. The target sites were confirmed to be related to false tendon. The origin of PVCs was located at the attachment of the false tendon to the papillary muscle, LV septum, or LV apex. At the target site, high-frequency Purkinje potentials were observed preceding local ventricular activation in 7 patients. CONCLUSION: LV false tendon can be associated with PVCs, which can be cured by RFCA. An ICE-guided electroanatomical approach should be considered to improve the safety and feasibility of this procedure.

Association Between Silent Myocardial Infarction and Long-Term Risk of Sudden Cardiac Death.

Background Although silent myocardial infarction (SMI) is prognostically important, the risk of sudden cardiac death (SCD) among patients with incident SMI is not well established. Methods and Results We examined 2 community-based cohorts: the ARIC (Atherosclerosis Risk in Communities) study (n=13 725) and the CHS (Cardiovascular Health Study) (n=5207). Incident SMI was defined as electrocardiographic evidence of new myocardial infarction during follow-up visits that was not present at the baseline. The primary study end point was physician-adjudicated SCD. In the ARIC study, 513 SMIs, 441 clinically recognized myocardial infarctions (CMIs), and 527 SCD events occurred during a median follow-up of 25.4 years. The multivariable hazard ratios of SMI and CMI for SCD were 5.20 (95% CI, 3.81-7.10) and 3.80 (95% CI, 2.76-5.23), respectively. In the CHS, 1070 SMIs, 632 CMIs, and 526 SCD events occurred during a median follow-up of 12.1 years. The multivariable hazard ratios of SMI and CMI for SCD were 1.70 (95% CI, 1.32-2.19) and 4.08 (95% CI, 3.29-5.06), respectively. The pooled hazard ratios of SMI and CMI for SCD were 2.65 (2.18-3.23) and 3.99 (3.34-4.77), respectively. The risk of SCD associated with SMI is stronger with White individuals, men, and younger age. The population-attributable fraction of SCD was 11.1% for SMI, and SMI was associated with an absolute risk increase of 8.9 SCDs per 1000 person-years. Addition of SMI significantly improved the predictive power for both SCD and non-SCD. Conclusions Incident SMI is independently associated with an increased risk of SCD in the general population. Additional research should address screening for SMI and the role of standard post-myocardial infarction therapy.

Redefining the Blanking Period by a Long-Term Follow-Up after Atrial Fibrillation Ablation Using Second-Generation Cryoballoon.

On the basis of radiofrequency ablation of atrial fibrillation (AF), some studies suggested that early recurrences of atrial tachyarrhythmia (ERATs) were associated with late AF recurrence (LAFR), and some also suspected and challenged the current recommended 90 day blanking period. We aim to evaluate the impact of ERAT on long-term success and to determine the optimum blanking period after AF ablation using second-generation cryoballoon (sg-CB). From August 2016 to October 2018, 369 consecutive patients who successfully underwent initial AF ablation using sg-CB at the Fuwai Hospital were finally enrolled. All patients were followed up no less than 12 months. Receiver operating characteristic curve analysis was used to determine the optimum blanking period after AF ablation. There were 62 (16.8%) who experienced ERAT. After a median follow-up of 615 days, 74.5% were free of LAFR after the 90 day blanking period. Incidence of freedom from LAFR during the long-term follow-up was markedly lower in patients with ERAT than in those without ERAT (27.4% versus 84.0%; log-rank P < 0.001). Furthermore, only ERAT (HR 8.579; 95% CI 5.604-13.133; P < 0.001) was significantly associated with an increased risk of LAFR after adjusting for other factors. The optimum cut-off time point for the blanking period was 21.5 days (sensitivity: 71.1%, specificity: 94.1%). In conclusion, ERAT was an independent predictor of LAFR after AF ablation using sg-CB. Based on our findings, blanking period was advised to be shorten to 21.5 days or about 3 weeks instead of 90 days after CB ablation.

The value of extensive catheter linear ablation on persistent atrial fibrillation (the CLEAR-AF Study).

BACKGROUND: The ablation therapy for persistent atrial fibrillation (PerAF) is still a challenge due to the high recurrence rate. This study was aimed to investigate the value of extensive linear ablation with contact force sensing techniques for PerAF. METHODS: A total of 214 patients with PerAF were enrolled in five centers. The patients were randomly assigned to Group I (PVI + LA roof line+ LA anterior wall line) and Group II (PVI + LA roof line), mitral valve isthmus lines were added in both groups if the atrial fibrillation (AF) could not be terminated after all approaches above. RESULTS: Acute success rate of AF termination during the ablation procedure in Group I was significantly higher than Group II (P = 0.028). Two-years follow-up showed no significant difference in the sinus rhythm maintenance rate between the two groups (63.4% in group I vs. 57.2% in group II, P = 0.218). More patients in Group I recurred as organized atrial tachycardia (AT) and can be precisely mapped during repeat ablation procedures (15 vs. 2, P = 0.001). The Kaplan-Meier estimates of AF/AT-free survival after repeat ablation procedures were 76.2% in Group I and 47.1% in Group II (P = 0.039). CONCLUSIONS: Extensive linear ablation with contact force monitoring did not improve the long-term outcomes for PerAF patients. Repeat ablation procedure showed a possible higher chance of sinus rhythm restoration during follow-up.

Catheter ablation of premature ventricular complexes associated with false tendons: A case report.

BACKGROUND: False tendon is a common intraventricular anatomical variation. It refers to a fibroid or fibromuscular structure that exists in the ventricle besides the normal connection of papillary muscle and mitral or tricuspid valve. A large number of clinical studies have suggested that there is a significant correlation between false tendons and premature ventricular complexes. However, few studies have verified this correlation during radiofrequency catheter ablation of premature ventricular complexes. CASE SUMMARY: A 45-year-old male was admitted to receive radiofrequency ablation for symptomatic premature ventricular complexes. A three-dimensional model of the left ventricle was established by intracardiac echocardiography using the CartoSoundTM mapping system. In addition to the left anterior papillary muscle, the posterior papillary muscle was mapped. False tendons were found at the base of the interventricular septum, and the other end was connected to the left ventricular free wall near the apex. An irrigated touch force catheter was advanced into the left ventricle via the retrograde approach. The earliest activation site was marked at the interventricular septum attachment of the false tendons and was successfully ablated. CONCLUSION: This case verified that false tendons can cause premature ventricular complexes and may be cured by radiofrequency ablation guided by intracardiac echocardiography with the CartoSoundTM system.

Early recurrence of atrial tachyarrhythmia during the 90-day blanking period after cryoballoon ablation in patients with atrial fibrillation: The characteristics and predictive value of early recurrence on long-term outcomes.

OBJECTIVE: To investigate the characteristics of early recurrence (ER) of atrial tachyarrhythmia (ATA) defined as atrial fibrillation (AF), atrial tachycardia (AT), or atrial flutter (AFL) during a 90-day blanking period after pulmonary vein isolation by cryoablation (PVI-C) in patients with symptomatic drug refractory AF. Specifically, to determine if ER of ATA during the blanking period can predict late recurrence (LR) during a 12-month follow-up period. METHOD: A total of 51 patients with symptomatic AF (who received PVI-C) were monitored by trans-telephonic wireless electrocardiogram (TWECG) event recording during the landmark 90-day blanking period following an index ablation. Recurrent ATA was defined as any AF, AT, or AFL lasting longer than 30 s (as recorded by 12­lead ECG, 24-hour Holter monitor, or TWECG). For data analysis, patients were grouped into ER and non-ER cohorts during the 90-day blanking period and then cohorted into LR or non-LR groups during the 12-month follow-up. RESULTS: During the 90-day blanking period, 23 patients had an ER event of ATA while 28 patients had a non-ER experience. Also, during the 12-month follow-up period, 15 patients had a LR event while 36 patients were free from ATA (and placed in the non-LR cohort). Overall, the average success rate of cryoablation for AF was 70.6% at the 12-month follow-up period. Compared to the non-LR group, patients with LR showed a higher average percentage of diabetes mellitic (33.3% vs. 5.56%; P = 0.008) and had a larger mean left atrium diameter (41.2 ±â€¯4.3 mm vs. 36.5 ±â€¯4.2 mm; P = 0.0006). During evaluation of the 90-day blanking period, the LR group had more frequent attacks of ATA than compared to the non-LR group (27.7% vs. 2.4%; P < 0.001). Only two patients (7.1%) without ER in the blanking period (non-ER cohort) had relapsed into a LR of ATA during the one-year period. After multi-logistic regression analysis, ER could individually predict the risk of LR (RR = 58.8; P = 0.001). CONCLUSION: In our study, ER of ATA was a common phenomenon during the 90-day blanking period after PVI-C for AF, and it mostly occurred in the first month following the index ablation across all patients. ER is not equal to the LR of ATA; however, patients with an ER event had a higher risk of a LR during the 12-month follow-up period.

Recurrence after successful catheter ablation for ventricular arrhythmia from the aortic root.

OBJECTIVE: The mechanism underlying recurrence after successful ablation of ventricular arrhythmias (VAs) was unclear. Spectrum analysis can help to identify near-field activation. The purpose of this study was to quantify the changes of near-field activation in response to ablation at the VAs origin in the aortic root (AR-VAs) and to assess its relationship with late ablation outcome. METHODS AND RESULTS: Patients who underwent acutely successful ablation for AR-VAs were analysed. Ventricular electrograms acquired before and after ablation at VAs origin were subjected to spectrum analysis. The area under the curve of the high frequency component (HFC, 50-200 Hz) and the low frequency component (LFC, 0-50 Hz) was measured. The proportion of HFC to the frequency spectrum of 0-200 Hz was defined as the HFC ratio (HFCR). The reduction of HFC and HFCR in response to ablation was defined as HFC pre-post and HFCR pre-post, respectively. Documentation of VAs with the same morphology after an acute successful procedure was defined as recurrence. Fifty-six patients were analysed, and VAs recurred in 17 patients. HFCR pre-post, HFC pre-post, and HFC pre-ablation were significantly higher in patients without recurrence. And HFCR pre-post has the highest predictive value (area under the receiver-operating characteristic curve: 0.975). A HFCR pre-post of 1.0% differentiated two groups (sensitivity = 84.6%, specificity = 100%). Higher HFCR pre-post was correlated with shorter VAs termination time (correlation coefficient = -0.399, p = .009). CONCLUSIONS: HFCR pre-post can quantify the near-field activation change during ablation. Incomplete destruction to the VAs foci could underlie recurrence after successful ablation.

Transoesophageal echocardiography prior to catheter ablation could be avoided in atrial fibrillation patients with a low risk of stroke and without filling defects in the late-phase MDCT scan: A retrospective analysis of 783 patients.

OBJECTIVES: To test whether multidetector computed tomography (MDCT) could completely replace transoesophageal echocardiography (TEE) to detect left atrial appendage (LAA) thrombi in atrial fibrillation (AF) patients using a large sample size. METHODS: 783 patients with AF who underwent MDCT and TEE before catheter ablation were retrospectively included. Demographic data were obtained. Two radiologists blinded to clinical data made the imaging diagnosis. RESULTS: Most of the patients (96.2 %) had a CHA2DS2-VASc score (congestive heart failure, hypertension, age ≥ 75 years old (doubled), diabetes, stroke/transient ischaemic attack/thromboembolism (doubled), vascular disease, age 65-74 years, female sex) ≤ 3. Eight thrombi were identified by TEE, all of which were detected by MDCT; no thrombus was observed with TEE without the observation of filling defects by late-phase MDCT scanning in any of the patients. Using TEE as reference standard, the sensitivity, specificity, positive predictive value and negative predictive value of MDCT for thrombus detection were 100 %, 95.74 % (95 % CI 94.33 %-97.15 %), 19.51 % (95 % CI 16.73 %-22.29 %) and 100 %, respectively. CONCLUSIONS: For AF patients with low risk of stroke, when MDCT images showed no filling defect in the late phase, TEE prior to catheter ablation can be avoided. KEY POINTS: • MDCT can help detect the presence of LAA thrombus. • TEE can be avoided when late-phase MDCT shows no filling defect. • TEE is required in patients whose MDCT images indicate thrombus.

Multiple Intercostal Space Electrocardiogram Allows Accurate Localization of Outflow Tract Ventricular Arrhythmia Origin.

BACKGROUND: Multiple intercostal recordings were supposed to get a more comprehensive view of the depolarization vector of the outflow tract ventricular arrhythmia (OT-VA), which may help to identify the OT-VA more accurately. This study was undertaken to develop a more accurate electrocardiogram (ECG) criterion for differentiating between left and right OT-VA origins. METHODS: We studied OT-VA with a left bundle branch block pattern and inferior axis QRS morphology in 47 patients with successful catheter ablation in the right ventricular OT (RVOT; n = 37) or aortic coronary cusp (ACC; n = 10). Superior and inferior precordial leads were taken together with the routine 12-lead ECG. The ECG during the OT-VA and during sinus beats were analyzed. Transition ratio, transition zone (TZ) index, R/S amplitude ratio, and R-wave duration ratio were measured in the regular, superior, and inferior precordial leads. RESULTS: The combined TZ index, TZ index inferior was significantly smaller, while the V2 inferior transition ratio was significantly larger for ACC origins than RVOT origins (P < 0.05). The area under the curve for the combined TZ index by a receiver operating characteristic analysis was 0.974, which was significantly larger than other parameters. A cutoff value ≤0.25 predicted an ACC origin with 94% sensitivity and 100% specificity. This advantage of the parameter over others also held true for a subanalysis of OT-VAs with a lead V3 precordial transition or TZ index = 0. CONCLUSIONS: The combined TZ index outperformed other ECG criteria to differentiate left from right OT-VA origins.

Electrocardiographic difference between ventricular arrhythmias from the right ventricular outflow tract and idiopathic right ventricular arrhythmias.

BACKGROUND: Ventricular arrhythmias (VA) arising from arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) and idiopathic right ventricular outflow tract ventricular arrhythmias (RVOT-VA) share the pattern of left bundle branch block (LBBB)/inferior axis. The existence of QRS notching showed a discriminating effect of the two conditions in recent research; however, there are little data regarding the difference in the distribution of QRS notching. The aim of this study was to compare the VA morphology between the two conditions, especially evaluating the diagnostic role of QRS notching. METHODS: Electrocardiographic (ECG) recordings of VA episode with LBBB/inferior axis of 16 ARVD/C and 45 idiopathic RVOT-VA patients (30 originated from the septum, 15 from the free-wall) were gathered and compared. RESULTS: ARVD/C had longer mean QRS duration in all 12 leads, and significant differences existed in leads Ⅰ,Ⅱ,Ⅲ, aVL, aVF, and V1 (P < 0.05). Lead Ⅰ had the largest mean difference of 25.1 ± 5.8 ms. In addition, ARVD/C had more R-wave transition in lead V5 or later (37.5% vs 8.9%, P < 0.01).The presence of QRS notching (15/16 [93.8%] vs 36/45 [80.0%], P = 0.20) and the total number of leads expressing notching (2.88 ± 2.0 vs 2.80 ± 2.0, P = 0.90) were not different between ARVD/C and idiopathic RVOT-VA. However, QRS notching existing simultaneously in leads I and aVL was more common in ARVD/C (43.8% vs13.3%, P = 0.011). CONCLUSION: Longer QRS duration, later precordial R/S transition, and QRS notching in lateral leads (leads Ⅰ and aVL) are useful in discriminating ARVD/C from idiopathic RVOT-VA.

Management of focal atrial tachycardias originating from the atrial appendage with the combination of radiofrequency catheter ablation and minimally invasive atrial appendectomy.

BACKGROUND: Focal atrial tachycardias (ATs) originating from the left and the right atrial appendage (AA) were the most difficult to eliminate. OBJECTIVE: To evaluate the safety and long-term efficacy of minimally invasive surgical atrial appendectomy in combination with radiofrequency catheter ablation (RFCA) in the management of focal atrial appendage tachycardias (AATs). METHODS: We included 42 consecutive patients with 42 AATs confirmed by activation mapping and contrast venography. Thirty of them were successfully managed with RFCA (RFCA-successful group), while the remaining 12 (28.6%) finally resorted to video-assisted thoracoscopic atrial appendectomy owing to RFCA failure (resort-to-surgery group). We searched for predictors of RFCA failure, and the need for surgery by using a binomial logistic regression model. RESULTS: In the RFCA-successful group, 6 (20.0%) patients experienced recurrence and re-do ablation and 11 (36.7%) AATs originated from distal AAs. In the resort-to-surgery group, the tachycardias involved exclusively distal AAs and required more RFCA attempts compared with those of the RFCA-successful group (1.58 ± 0.51 vs 1.20 ± 0.41; P = .0165). During atrial appendectomy, incessant ATs were terminated immediately after resection of the AA at the base. Long-term success was achieved in all 42 patients with a follow-up of 29.1 ± 17.5 months. No complications occurred. Fourteen patients with tachycardia-induced cardiomyopathy recovered fully. We identified origin at distal AATs and longer time to tachycardia termination by ablation as predictors of RFCA failure and the need for surgical intervention. CONCLUSION: ATs originating from the distal portion of AA were more refractory to RFCA. The combination of catheter ablation and video-assisted thoracoscopic atrial appendectomy was an effective strategy to manage AATs.

Idiopathic ventricular fibrillation with fragmented QRS complex and J wave in resting electrocardiogram.

OBJECTIVE: To describe the clinical characteristics of idiopathic ventricular fibrillation (IVF) with fragmented QRS complex (f-QRS) and J wave in resting electrocardiogram. METHODS: We reviewed data from 21 case subjects in our hospital who were resuscitated after cardiac arrest due to IVF and assessed the prevalence of f-QRS and J wave in resting electrocardiogram (ECG). All the case subjects were classified among three groups based on the electrocardiographic morphology: group I, both f-QRS and J wave were observed (n = 6), group II, only J wave was observed (n = 9), group III, neither f-QRS nor J wave was observed (n = 6). Population characteristics, history of syncope or sudden cardiac arrest, incidence of ventricular fibrillation (VF), and circumstance of VF were evaluated among the three groups. RESULTS: The incidence of index events (syncope, survived cardiac arrest and VF episodes recorded in implantable cardioverter defibrillator (ICD) or pacemakers) was 13.4 ± 5.6 per-year in group I, 10.8 ± 3.9 per-year in group II, and 9.8 ± 4.2 per-year in group III. There were significant differences in incidences among the three groups, the most frequent index events were observed in group I. The hazard ratio for incidence was 3.2 (95%CI, 1.1-7.9; P = 0.01). The history and circumstance of the index events were different among the groups. In group I, all the index events occurred during sleep in early morning. In group II, four subjects suffered VF during strenuous physical activities or agitation state, two during sleep in early morning, three in usual activity. In group III, one subject suffered VF during sleep in early morning, one in agitation state, four in usual activity. CONCLUSIONS: This study suggests that the IVF patients with the combined appearance of f-QRS and J wave in the resting ECG suffer an increased risk of VF, this subgroup of IVF patients has a unique clinical feature.

Identification of the slow conduction zone in a macroreentry circuit of verapamil-sensitive idiopathic left ventricular tachycardia using electroanatomic mapping.

BACKGROUND: Although idiopathic left ventricular tachycardia (ILVT) has been shown to possess a slow conduction zone (SCZ), the details of the electrophysiological and anatomic aspects are still not well understood. OBJECTIVE: We hypothesized that the SCZ can be identified using a 3-dimensional electroanatomic (EA) mapping system. METHODS: Ten patients with ILVT were mapped using a 3-dimensional electroanatomic (EA) mapping system. After a 3-dimensional endocardial geometry of the left ventricular was created, the conduction system with left Purkinje potential (PP) and the SCZ with diastolic potential (DP) in LV were mapped during sinus rhythm (SR) and ventricular tachycardia (VT) and were tagged as special landmarks in the geometry. The electrophysiological and anatomic aspects of it were investigated. RESULTS: EA mapping during SR and VT was successfully performed in 7 patients, during VT in 3 patients. The SCZ with DPs located at the inferoposterior septum was found in 7 patients during SR and all patients during VT. The length of the SCZ was 25.2 ± 2.3 mm with conduction velocity 0.08 ± 0.01 m/s. No differences in these parameters were found between patients during SR and VT (P > 0.05). An area with PP was found within the posterior septum. A crossover junction area with DP and PP was found in 7 patients during SR and VT. This area with DP and PP during SR coincided or were in proximity to such area during VT and radiofrequency ablation targeting the site within the area abolished VT in all patients. CONCLUSION: The ILVT substrate within the junction area of the SCZ and the posterior fascicular can be identified and can be used to guide the ablation of ILVT.

[Association between abnormal electrocardiographic features and disease severity in patients with arrhythmogenic right ventricular cardiomyopathy].

OBJECTIVE: To analyze the relationship between electrocardiographic (ECG) features and disease severity in patients with the arrhythmogenic right ventricular cardiomyopathy (ARVC). METHOD: The study group consisted of 61 subjects with a definite diagnosis of ARVC on the basis of published guideline criteria and patients were divided into 3 subgroups according to the extent of diseased myocardium defined by cardiac magnetic resonance imaging (MRI): Group A: local involvement (n = 19, 31%), Group B: diffuse involvement of whole right ventricle (n = 28, 46%) and Group C: involvement of both right and left ventricles (n = 14, 23%). RESULTS: Normal electrocardiogram was shown in 1 patient in each group. Epsilon wave was detected in 24 (39%) patients, QRS duration was prolonged [≥ 110 ms (V(1)-V(3))] in 21 (34%) patients, S-wave upstroke was prolonged (≥ 55 ms) in 17 (28%) patients, complete right branch bundle block was evidenced in 10 (16%) patients and pathologic Q waves was found in 9 (15%) patients. The incidence of above abnormal ECG changes was increased in proportion to the degree of disease severity (group A < group B < group C). Incidence of Epsilon wave and prolonged QRS duration [ ≥ 110 ms (V(1)-V(3))] were significantly higher in Group C than in Group A. Incidence of prolonged S-wave upstroke (≥ 55 ms) was significantly higher in Group C than in Group A and Group B. T-wave inversion in V(1) leads was often found in Group A. T-wave inversion in inferior leads (V(1)-V(3) leads or beyond V(3)) was often presented in Group B and Group C. CONCLUSIONS: Normal ECG does not exclude the possibility of diagnosis of ARVC. The extent of T-wave inversion in the precordial leads and incidence of Epsilon wave, prolonged QRS duration [ ≥ 110 ms (V(1)-V(3))] and prolonged S-wave upstroke (≥ 55 ms) were related to degree of disease severity in patients with ARVC.

Right phrenic injury after radiofrequency catheter ablation of atrial tachycardia at crista terminalis.

A 62-year-old woman with frequent occurrence of symptomatic atrial tachycardia with a foci located at the root of the upper crista terminalis was found to have right diaphragm paresis after receiving a total of 8 radiofrequency energy deliveries (40-60 W, 50-60ºC) and a total duration of 540 seconds of ablation therapy (7Fr 8 mm deflectable ablation catheter). The right diaphragm paresis remained resolved up to 14 months after the procedure as confirmed by repeated chest X-rays.