Initial studies on the implanting sites of high and low ventricular septa using leadless cardiac pacemakers.

OBJECTIVE: To study the safety and electrical characteristics of various implanting sites of the Micra pacemaker. METHOD: A total of 15 patients from Beijing Anzhen Hospital, Capital Medical University, were included, who were implanted with Micra leadless pacemakers and allocated to either the high ventricular septum group (eight patients) or the low ventricular septum group (seven patients) based on their individual patient factors and clinical conditions. The baseline of the patients, the implanting area, the electrocardiogram change after implantation, the implantation data, the threshold, R wave, impedance, and the date of the 1-month follow-up were then analyzed. With all of the data, the characteristics of different implantation sites of the Micra pacemaker were determined. RESULTS: Overall, the thresholds were low at implantation and remained stable over the 1-, 3-, 6-month, 1-, 2-, 3-, and 4-year follow-ups. On comparing the two groups, there was no difference in QRS duration at pacing (140.00 [40.00] ms vs. 179.00 [50.00] ms), threshold at implantation (0.38 [0.22] mV vs. 0.63 [1.00] mV), R wave at implantation ([10.85 ± 4.71] V vs. [7.26 ± 2.98] V), or impedance at implantation ([906.25 ± 162.39] Ω vs. [750.00 ± 173.40] Ω). While the difference in QRS duration between the two groups was not significant, the QRS duration of the high ventricular septum group exhibited a reduced tendency compared with that of the low ventricular group. The corrected QT interval during pacing exhibited a significant difference (440.00 [80.00] ms vs. 520.00 [100.00] ms; p < .05). For the 1-, 3-, 6-month, 1-, 2-, 3-, and 4-year follow-ups, there was no difference between the threshold of the high ventricular septum group and that of the low ventricular septum group (p > .05). CONCLUSION: High ventricular septum pacing appears to be a safe site for implantation of the Micra pacemaker. It could entail a shorter QRS duration at pacing and could be more physiological than low ventricular septum pacing.

A tiled multi-city urban objects dataset for city-scale building energy simulation.

City-scale building energy simulation provides a significant reference for planning and urban management. However, large-scale building energy simulation is often unfeasible due to the huge amount of computational resources required and the lack of high-precision building models. For such reasons, this study developed a tiled multi-city urban objects dataset and a distributed data ontology. Such a data metric not only transforms the conventional whole-city simulation model into patch-based distributed simulations but also incorporates interactive relationships among objects in cities. The dataset stores urban objects (8,196,003 buildings; 238,736 vegetations; 2,381,6698 streets; 430,364 UrbanTiles; 430,464 UrbanPatches) from thirty major cities in the United States. It also aggregated morphological features for each UrbanTile. To validate the performance of the developed dataset, a sample test was conducted in one city subset (Portland). The results conclude that the linear increase of time usage of modeling and simulation with the increase of building numbers. With the tiled data structure, the proposed dataset is also efficient for the building microclimate estimation.

Catheter ablation of ventricular premature depolarizations originating from the mid interventricular septum: Significance of electrocardiographic morphology for predicting origin.

BACKGROUND: Ventricular premature depolarizations (VPDs) originating from the mid interventricular septum (IVS) adjacent to the atrioventricular annulus between the His bundle and the coronary sinus ostium (mid IVS VPDs) have not been characterized. OBJECTIVE: The aim of this study was to investigate the electrophysiological characteristics of mid IVS VPDs. METHODS: Thirty-eight patients with mid IVS VPDs were enrolled. VPDs were divided into different types according to precordial transition of the electrocardiogram (ECG) and QRS morphology in lead V1. RESULTS: Four types of VPDs were divided. The precordial transition zone appeared earlier and earlier from types 1 to 4. The notch in lead V1 moved gradually backward, and its amplitude gradually became higher, resulting in the transition from left to right bundle branch block morphology in lead V1 from types 1 to 4. Based on activation and pace mapping, ablation response, and 3830 electrode pacing morphology in the mid IVS, the 4 types of ECG morphology corresponded to an origin in the right endocardial side, right/mid intramural region, left intramural region, and left endocardial side of the mid IVS, respectively. An intramural origin was identified for 50% of VPDs. Eighty-nine percent of mid IVS VPDs could be eliminated. Bilateral ablation (waiting for delayed efficacy) or bipolar ablation was sometimes needed for intramural VPDs. CONCLUSION: Mid IVS VPDs were found to have unique electrophysiological characteristics. The ECG characteristics of mid IVS VPDs were important in terms of prediction of its exact origin, the choice of ablation method, and the likelihood of treatment being successful.

Occurrence of ventricular septal perforation in patients with permanent left bundle branch pacing followed up using echocardiographic and computed tomography images.

OBJECTIVE: To explore short-term changes after left bundle branch pacing (LBBP) using echocardiography and computed tomography (CT), especially for postoperative ventricular septal perforation. METHODS: Between January and September 2019, 33 patients with atrioventricular block underwent LBBP at Beijing Anzhen Hospital. All the patients were evaluated using electrocardiography, pacing, parameters and echocardiographic measurements, including for major complications, during the 1, 3, 6, 12 and 24-month follow-up. Interval perforations were examined during a 1-month follow-up echocardiogram and CT. RESULTS: Left bundle branch pacing was successfully performed in 100% (33/33) of patients. The mean seizure threshold was stable and unchanged postoperatively at the 1, 3, 6, 12 and 24-month follow-up. The paced QRS duration of the LBBP was 119.72 ± 2.53 ms and <130 ms in all patients. Unipolar impedance during the procedure was higher than 500 Ω (662.00 ± 181.50 Ω). No ventricular septal perforation occurred at the end of the procedure. At the 1-month follow-up, two patients reported transthoracic echocardiography, with CT revealing septal lead perforation. Through CT, two other patients were found to have septal lead perforation, and echocardiography indicated that the pacing lead had penetrated the interventricular septum and entered the left subendocardium. At the 1, 3, 6, 12 and 24-month follow-up, these four patients exhibited no significant increase in pacing threshold or impedance (p > .05). No ventricular thrombus or stroke was detected. CONCLUSION: Permanent LBBP is safe and feasible in patients with bradycardia. Echocardiography and/or CT can more accurately evaluate changes in cardiac structure and function after LBBP.

Perceptual decision-making 'in the wild': How risk propensity and injury exposure experience influence the neural signatures of occupational hazard recognition.

While previous studies have extensively explored the neural mechanisms of perceptual decision-making, most of them used paradigms with limited real-life consequences and largely neglected participants' individual differences. In this study, to resemble a perceptual decision-making scenario with real-life consequences, construction workers were recruited for an occupational hazard recognition task by categorizing construction site images as hazardous or safe with their EEG recorded. Event-related potential (ERP) analysis revealed distinct influences of perceptual decision-making by two dispositional factors of risk propensity and injury exposure experience. Risk propensity was positively correlated with the stimulus-locked difference waveforms (hazardous minus safe) at approximately 200 ms post-stimuli-onset over right-lateralized parietal-occipital areas. The difference waveforms showed reversed polarity between groups with high and low-risk propensity. Injury exposure experience was negatively correlated with the response-locked difference waveforms approximately 450 ms before motor response over right-lateralized parietal-occipital regions. To the best of our knowledge, this study is the first to report how individuals' injury exposure experience influenced the neural signatures of one's perceptual decision-making. These results extended previous findings for perceptual decision-making by setting up a scenario with high ecological validity and suggested possibly substantial different mechanisms for individual workers by the intrinsic factor of risk propensity and the extrinsic factor of injury exposure experience.

Optimizing safety-measure combinations to address construction risks.

Objectives. Most methods used to develop construction risk responses address the risk-mitigation optimization problem by solving the objective functions. They are passively achieved by satisfying constraint conditions, which are not adequate for efficient construction management. This study aims to provide an active optimization strategy for selecting risk responses. Methods. We combined set pair analysis (SPA) with the technique for order preference by similarity to an ideal solution (TOPSIS) to control the construction risks to an acceptable level instead of excessively to the minimum level. SPA is employed to assess the pre-mitigation and post-mitigation risk levels based on the uncertainty theory, and the TOPSIS is used to rank safety measures based on their risk-mitigation effects. A case study of concrete pumping for a super high-rise building was used to exemplify how the proposed optimization model assists risk control and to validate its reasonability. Conclusion. The developed TOPSIS-SPA-based method figures out the optimal safety-measure combination reducing construction risks economically to an acceptable level with the fewest number of measures. The findings can assist decision-makers in formulating cost-effective risk-control schemes.

Sustained sustainable development actions of China from 1986 to 2020.

Achieving the Sustainable Development Goals (SDGs) is a long-term task, which puts forward high requirements on the sustainability of related policies and actions. Using the text analysis method, we analyze the China National Sustainable Communities (CNSCs) policy implemented over 30 years and its effects on achieving SDGs. We find that the national government needs to understand the scope of sustainable development more comprehensively, the sustained actions can produce positive effects under the right goals. The SDGs selection of local governments is affected by local development levels and resource conditions, regions with better economic foundations tend to focus on SDGs on human well-being, regions with weaker foundations show priority to basic SDGs on the economic development, infrastructures and industrialization.

Large-scale public venues as medical emergency sites in disasters: lessons from COVID-19 and the use of Fangcang shelter hospitals in Wuhan, China.

Since the COVID-19 outbreak, Wuhan has adopted three methods of admitting patients for treatment: designated hospitals, newly built temporary hospitals and Fangcang shelter hospitals. It has been proven that converting large-scale public venues such as stadiums and exhibition centres into Fangcang shelter hospitals, which serve as hospitals for isolation, treatment and disease monitoring of patients with mild symptoms, is the most effective way to control virus transmission and reduce mortality. This paper presents some experiences learnt from treating COVID-19 in Wuhan, the first city to report the outbreak and which suffered from a shortage of emergency supplies, heavy workload among staff and a shortage of hospital beds during the early stages of the pandemic. The experiences include location, accessibility, spacious outdoor area, spacious indoor space, power supply, architectural layout design and partition isolation, ventilation, sewage, and problems in the construction and management of Fangcang shelter hospitals. During the COVID-19 pandemic, traditional approaches to disaster preparedness have demonstrated intrinsic problems, such as poor economic performance, inefficiency and lack of flexibility. Converting large-scale public venues into Fangcang shelter hospitals is an important means to rapidly improve the function of the city's healthcare system during a pandemic. This valuable experience in Wuhan will help other countries in their battle against the current COVID-19 pandemic and will also contribute to disaster preparedness and mitigation in the future.

Initial experience with ablation of the innervation surrounding sinus and atrioventricular nodes to treat paroxysmal bradyarrhythmia.

BACKGROUND: The symptomatic bradyarrhythmia is Class I indication for pacing therapy which is not a radical cure. The present study aimed to assess the feasibility and to present the initial results of the restricted ablation of the parasympathetic innervation surrounding sinus and atrioventricular (AV) nodes for treating patients with bradyarrhythmia. METHODS: A total of 13 patients with cardiogenic syncope were included from May 2008 to June 2015. Under the guidance of fluoroscopy and /or three-dimensional geometry by 64-slice spiral computed tomography, atrial activation sequence in sinus rhythm was mapped. Chamber geometry was reconstructed manually or automatically using the Niobe II magnetic navigation system integrated with the CARTO-remote magnetic technology (RMT) system. Cardioneuroablation was targeted at the high-amplitude fractionated electrograms surrounding the regions of His bundle and the site with the earliest activation in sinus rhythm. Areas surrounding the sinus node, AV node, and the phrenic nerve were avoided. RESULTS: Thirteen patients completed the studies. Ablation was successfully performed in 12 patients and failed in one. The high-frequency potential was recorded in atrial electrograms surrounding the sinus or AV nodes in all the patients and disappeared in 15 s after radiofrequency applications. The vagal reaction was observed before the improvement of the sinus and AV node function. No complications occurred during the procedures. Patients were followed up for a mean of 13.0 ±â€Š5.9 months. During the follow up ten patients remained free of symptoms, and two patients had a permanent cardiac pacemaker implanted due to spontaneous recurrence of syncope. The heart rate of post-ablation was higher than pre-ablation (69.0 ±â€Š11.0 vs. 49.0 ±â€Š10.0 beats/min, t = 4.56, P = 0.008). The sinus node recovery time, Wenckebach block point, and atrium-His bundle interval were significantly shorter after ablation (1386.0 ±â€Š165.0 vs. 921.0 ±â€Š64.0 ms, t = 7.45, P = 0.002; 590.0 ±â€Š96.0 vs. 464.0 ±â€Š39.0 ms, t = 2.38, P = 0.023; 106.0 ±â€Š5.0 vs. 90.0 ±â€Š12.0 ms, t = 9.80, P = 0.013 before and after ablation procedure, respectively). CONCLUSIONS: Ablation of sinoatrial and AV nodal peripheral fibrillar myocardium electrical activity might provide a new treatment to ameliorate paroxysmal sinus node dysfunction, high degree AV block, and vagal-mediated syncope.

Falls from Height in the Construction Industry: A Critical Review of the Scientific Literature.

Globally, falls from height (FFH) are a substantial public health jeopardy and are among the important leading causes of serious and fatal injuries for construction workers. A comprehensive understanding of the causal factors in FFH incidents is urgently required; however, the literature appears to lack a scientific review of FFH. In this study, 297 articles that contribute to the topic of fall incidents were reviewed. Seventy-five (75) articles met the criteria for relevance and were aggregated in a database to support a critical review. A synthesis of macro-variables approach was adopted rather than a structured meta-analysis. Such a method of analysis provides the flexibility to combine previous studies' findings. The most common factors associated with FFH are risky activities, individual characteristics, site conditions, organizational characteristics, agents (scaffolds/ladders) and weather conditions. The outcomes contributed to identifying the most significant research area for safety enhancement by improving engineering facilities, behaviour investigations and FFH prevention methods.

The Effects of Dinner-to-Bed Time and Post-Dinner Walk on Gastric Cancer Across Different Age Groups: A Multicenter Case-Control Study in Southeast China.

Gastric cancer (GC) remains a major killer throughout the world. Despite the dramatic decrease in GC over the last century, its etiology has not yet been well characterized. This study investigated the possible independent and combined effects of the dinner-to-bed time and post-dinner walk on the risk for GC across different age groups. A population-based, case-control study was conducted in southeast China, including 452 patients with GC and 465 age-, race-, and gender-matched controls. A self-designed questionnaire was used to collect information on demographic characteristics, dinner-to-bed time, post-dinner walk, and other behavioral factors. Conditional logistic regression models were used to estimate the effects of the dinner-to-bed time and post-dinner walk as well as their joint effect on the risk for GC across different age groups. Individuals with dinner-to-bed time <3 hours were more prone to have GC (P < 0.001), and the shorter the dinner-to-bed time was, the higher was the risk for GC (Ptrend < 0.001). Post-dinner nonwalk was associated with a 2.9-fold increased risk for GC compared with post-dinner walk (adjusted odds ratio [AOR] = 2.942, 95% confidence intervals [95% CIs] = 2.072-4.179). The interaction effect of dinner-to-bed time and post-dinner walk on GC risk was detected (AOR = 1.862, 95% CIs = 1.584-3.885, synergy index [SI] = 2.654, 95% CIs = 2.27-3.912). Participants with dinner-to-bed time <3 hours who did not walk after dinner were 7.4 times likely to suffer from GC (AOR = 7.401, 95% CIs = 4.523-13.16) than those with dinner-to-bed time ≥4 hours who took such walk. The risk of GC due to dinner-to-bed time <3 hours, post-dinner nonwalk and their interaction was positively correlated with age. The strongest risk was observed among people ≥70 years old, but the effects were not significant for people ≤55 years old. Dinner-to-bed time <3 hours and post-dinner nonwalk are independent risk factors for GC; the synergistic interaction between the 2 factors was positively related to age, which might significantly increase the risk for GC among people >55 years old.

Clinical observations of supraventricular arrhythmias in patients with brugada syndrome.

OBJECTIVE: To study various types of supraventricular arrhythmias in patients with Brugada Syndrome. METHODS: Forty six patients with ECG of spontaneous type Brugada and with ventricular and/or supraventricular tachyarrhythmia, without structural heart diseases which were excluded by echocardiography, underwent 24 h-Holter recording, electrophysiological study and/or radiofrequency ablation. RESULTS: There were thirty-nine male and seven female (mean age 37.44 years) among total forty-six patients. Twenty one patients had family histories of tachycardia, twentythree patients experienced episodes of syncope, and three patients were resuscitated from cardiac arrest. One patient had ventricular fibrillation and third degree atrioventricular block, eleven patients had polymorphic ventricular tachycardia and five patients had monomorphic ventricular tachycardia. Fourteen patients had atrial tachyarrhythmia, paroxysmal supraventricular tachycardia was found in five patients including four Wolf-Parkinson-White syndrome, two patients hadventricular tachycardia and third degree atrioventricular block, one of them had atrial fibrillation, two patients had both supraventricular tachycardia and ventricular tachycardia, three patients had both atrial tachyarrhythmia and supraventricular tachycardia, two third degree atrioventricular block patients had atrial flutter, one patienthad both atrial tachyrhythmia and ventricular tachycardia. Radiofrequency blation was performed in thirty-nine patients and succeed in thirty-two, four patients were implanted with pacemakers, and four patients had implantable cardioverter defibrillators. CONCLUSION: In addition to ventricular tachycardia and ventricular fibrillation, patients with Brugada syndrome exhibit various supraventricular tachyarrhythmia and third degree atrioventricular block. In patients with Brugada syndrome, the dysfunction of the cardiac ion channel, which related to mutation of cardiac sodium channelgene, is not limited in His Purkinje system and ventricular myocardium, but also in the atrium and atrioventricular node, which may serves as a cause of dispersion of repolarization and phase 2 reentry leading to various arrhythmias.

[Effects of irrigation amount and various fertigation methods on yield and quality of cucumber in greenhouse].

Taking cucumber as experimental plant, an experiment was conducted to study the effects of irrigation amount and fertigation methods on growth, yield and quality of cucumber in greenhouse. The experiment had designed two irrigation levels, i.e. 100% ET0 (W1) and 75% ET0 (W2), and four fertigation fertilization ratios, i.e. 100%, 66.6%, 33.3% and 0% (Z100, Z66 , Z33, Z0) fertigation of a total amount of (360:180:540 kg · hm(-2)) (N:P2O5:K2O) by 8 times with the corresponding remainders (0%, 33.3%, 66.6% and 100%) were applied to soil as basic fertilization before the planting according to the recommended fertilization rate, and no fertilizer treatment was set up as the control (CK). Results showed that irrigation and fertilization levels had positive correlations with plant height, leaf areas, dry mass, yield and quality of cucumber. Yield at W1Z100 was the highest, reaching 67760 kg · hm(-2). W2 treatment increased the mean water use efficiency (WUE) by 9.4% compared to W1. W2Z100 treatment had the highest WUE, reaching 47.13 kg · m(-3). Yield at W2Z100 was only 3.4% lower than the maximum, but saved 25% of water. Yield and dry matter at Z100 were 15.3% and 16.8% higher than at Z0, respectively, the cucumber fruit vitamin C, soluble protein and soluble sugar contents were increased, and the water use efficiency was increased by 19.1%. W2Z100 treatment was the best treatment which could enable cucumber to obtain both the high-yield and the high-quality.

Development and validation of a fatigue assessment scale for U.S. construction workers.

OBJECTIVE: To develop a fatigue assessment scale and test its reliability and validity for commercial construction workers. METHODS: Using a two-phased approach, we first identified items (first phase) for the development of a Fatigue Assessment Scale for Construction Workers (FASCW) through review of existing scales in the scientific literature, key informant interviews (n = 11) and focus groups (three groups with six workers each) with construction workers. The second phase included assessment for the reliability, validity, and sensitivity of the new scale using a repeated-measures study design with a convenience sample of construction workers (n = 144). RESULTS: Phase one resulted in a 16-item preliminary scale that after factor analysis yielded a final 10-item scale with two sub-scales ("Lethargy" and "Bodily Ailment"). During phase two, the FASCW and its subscales demonstrated satisfactory internal consistency (alpha coefficients were FASCW [0.91], Lethargy [0.86] and Bodily Ailment [0.84]) and acceptable test-retest reliability (Pearson Correlations Coefficients: 0.59-0.68; Intraclass Correlation Coefficients: 0.74-0.80). Correlation analysis substantiated concurrent and convergent validity. A discriminant analysis demonstrated that the FASCW differentiated between groups with arthritis status and different work hours. CONCLUSIONS: The 10-item FASCW with good reliability and validity is an effective tool for assessing the severity of fatigue among construction workers.

Transient ST-segment elevation after transseptal puncture for atrial fibrillation ablation in two cases.

The present report demonstrates two cases of transient inferior ST-segment elevation accompanied by profound hypotension and bradycardia immediately after transseptal puncture for catheter ablation of atrial fibrillation. This rare complication of transseptal puncture was resolved quickly within several minutes. The most likely mechanism of this phenomenon is coronary vasospasm, although coronary embolism can not be ruled out completely. This complication is characterized as follows: (1) The right coronary artery might be the most likely involved vessel and therefore myocardial ischemia usually occurs in the inferior wall of left ventricular; (2) Reflex hypotension and bradycardia by the Bezold-Jarisch reflex secondary to inferior ischemia often occur at the same time. Though it appears to be a transient and completely reversible phenomenon, there are still potential life-threatening risks because of myocardial ischemia and profound haemodynamic instability. Clinical cardiologists should be aware of this rare complication and properly deal with it.

Ultrasonic destruction of albumin microbubbles enhances gene transfection and expression in cardiac myocytes.

BACKGROUND: It has been proven that ultrasonic destruction of microbubbles can enhance gene transfection efficiency into the noncardiac cells, but there are few reports about cardiac myocytes. Moreover, the exact mechanisms are not yet clear; whether the characteristic of microbubbles can affect the gene transfection efficiency or not is still controversial. This study was designed to investigate whether the ultrasound destruction of gene-loaded microbubbles could enhance the plasmids carried reporter gene transfection in primary cultured myocardial cell, and evaluate the effects of microbubbles characteristics on the transgene expression in cardiac myocytes. METHODS: The ß-galactosidase plasmids attached to the two types of microbubbles, air-contained sonicated dextrose albumin (ASDA) and perfluoropropane-exposed sonicated dextrose albumin (PESDA) were prepared. The gene transfection into cardiac myocytes was performed in vitro by naked plasmids, ultrasound exposure, ultrasonic destruction of gene-loaded microbubbles and calcium phosphate precipitation, and then the gene expression and cell viability were analyzed. RESULTS: The ultrasonic destruction of gene-loaded microbubbles enhanced gene expression in cardiac myocytes compared with naked plasmid transfection ((51.95 ± 2.41) U/g or (29.28 ± 3.65) U/g vs. (0.84 ± 0.21) U/g, P < 0.01), and ultrasonic destruction PESDA resulted in more significant gene expression than ASDA ((51.95 ± 2.41) U/g vs. (29.28 ± 3.65) U/g, P < 0.05). Ultrasonic destruction of microbubbles during calcium phosphate precipitation gene transfection enhanced ß-galactosidase activity nearly 8-fold compared with calcium phosphate precipitation gene transfection alone ((111.35 ± 11.21) U/g protein vs. (14.13 ± 2.58) U/g protein, P < 0.01). Even 6 hours after calcium phosphate precipitation gene transfection, ultrasound-mediated microbubbles destruction resulted in more intense gene expression ((35.63 ± 7.65) U/g vs. (14.13 ± 2.58) U/g, P < 0.05). CONCLUSIONS: Ultrasonic destruction of microbubbles might be a promising method for the delivery of non-viral DNA into cardiac myocytes, and the gene tranfection is related to the characteristics of microbubbles.

Ablation of right-sided accessory pathways with atrial insertion far from the tricuspid annulus using an electroanatomical mapping system.

BACKGROUND: It is difficult to ablate a right-sided accessory pathway (AP) with atrial insertion far from the tricuspid annulus (TA). We report our initial experience of ablating this rare AP by a 3-dimensional electroanatomical mapping system (CARTO). METHODS: From January of 2006 to April of 2008, 18 patients with right-sided APs who failed previous outside ablations were enrolled in this study. Retrograde AP conduction was mapped during pacing at the right ventricular apex by activation-mapping the right atrium (RA) using a 3-dimensional electroanatomical mapping system. AP atrial insertion was defined as the earliest retrograde atrial activations and successful ablation of the APs at this site. RESULTS: Among the 18 patients who had failed previous ablation, 10 patients (7 patients with right manifest APs and 3 patients with right conceal APs) had atrial insertions far from the TA. Of the 10 patients, the atrial insertions were found at the base of the RA appendage in 3 patients, at the high lateral RA in 5 patients, at the low lateral RA in other 2 patients. Ablation at the atrial insertions successfully abolished the AP conduction. The mean distance between the atrial insertion sites and the TA was 20.2 ± 2.7 mm. No patients reported recovered AP conduction or recurrent tachycardias after 6-month follow-up. CONCLUSIONS: The right-sided APs may have atrial insertion far from the TA. These uncommon variation of APs can be reliably identified and ablated using CARTO system.

Characteristics in image integration system guiding catheter ablation of atrial fibrillation with a common ostium of inferior pulmonary veins.

BACKGROUND: Common ostium of the inferior pulmonary veins (PVs) is a kind of unusual variation in pulmonary venous drainage to the left atrium (LA), whose feature of anatomy, electrophysiology, and catheter ablation is rarely demonstrated, and the consecutive series of research for catheter ablation of atrial fibrillation (AF) in patients with that anomaly have not been reported. METHODS: A total of 1,226 patients with drug-refractory AF received magnetic resonance angiography (MRA) or multidetector computed tomography (MDCT) scan before ablation. Electrophysiological mapping was used to detect the focal triggers in paroxysmal AF. Basic catheter ablation strategy was circumferential PV isolation with "tricircle" under the guidance of image integration system: two circles surround two superior PVs, and the other surround the common trunk. RESULTS: LA and PVs reconstruction by image integration system showed a common pulmonary venous ostium of the right and left inferior PVs before ablation in 11 patients (0.9%). This anomaly could be classified into two types: type A without a short common trunk of inferior PVs and type B with a short common trunk. Fifty-seven percent paroxysmal AF was revealed focal triggers in the common ostium. The success rate of that strategy was 90%. CONCLUSION: Common ostium of inferior PVs could be classified into two types according to the presence of a short common trunk or not. The common ostium was usually an important triggering focus in paroxysmal AF. Catheter ablation strategy of circumferential PV isolation with "tricircle" under the guidance of image integration system would be a good choice.