P5652Catheter ablation outcome and heart failure hospitalization in atrial fibrillation patients with preserved left ventricular ejection fraction: insights from the Kansai plus atrial fibrillation (KPAF)

Background

Heart failure (HF) is the leading cause of death in patients with atrial fibrillation (AF), and AF is an independent prognostic factor in HF patients with preserved left ventricular ejection fraction (LVEF). Radiofrequency catheter ablation (RFCA) for AF is effective to maintain sinus rhythm.

Purpose

We sought to clarify incidence of HF hospitalization and whether AF ablation outcome influenced incidence of HF hospitalization after the procedures in patients with preserved LVEF.

Methods

We conducted a large-scale, prospective, multicenter, observational study. A total of 4522 consecutive patients with normal LVEF (>/- 50%) who underwent an initial RFCA for AF in 26 centers were enrolled (average age, 64±10 years; non-paroxysmal AF, 33.7%). The median follow-up duration was 2.9 years.

Results

The 3-year cumulative incidence of AF recurrence after a single procedure was 40.3%. Hospitalization for HF was observed in 60 patients (1.3%) and was significantly higher in patients with AF recurrence than those without it (2.63% vs 0.44%, log-rank p<0.001). After adjustment by age ≥65 years, estimated glomerular filtration rate ≤60ml/min, history of HF, and female, all of which were statistically associated with a risk of HF hospitalization, AF recurrence after the index RFCA was an independent predictor of HF hospitalization (hazard ratio; 4.75, 95% confidence interval; 2.59–9.42, p<0.001).

Conclusions

Recurrence after RFCA for AF was a significant risk of HF hospitalization among AF patients with preserved LVEF.

Acknowledgement/Funding

This study was supported by the Research Institute for Production Development in Kyoto, Japan.

P6402Ischemic and bleeding events during dual antiplatelet therapy after second-generation drug-eluting stent implantation in hemodialysis patients: a propensity score-matched analysis

Background

Dual-antiplatelet therapy (DAPT) after second-generation drug eluting stent (2-DES) implantation reduced the risk of stent thrombosis and subsequent ischemic events, with an increase in bleeding risk. Although chronic kidney disease patients have high ischemic and bleeding risk, little is known about both risks in hemodialysis patients after 2-DES implantation during DAPT.

Method

From July 2009 to March 2017, we retrospectively analyzed post-discharge major adverse cardiac and cerebrovascular events [MACCE: cardiac death, myocardial infarction, target vessel revascularization (TVR) and cerebral infarction] and bleeding events in 644 consecutive patients during DAPT after 2-DES implantation. We divided them into 2 groups [102 hemodialysis (HD) and 518 non-hemodialysis (Non-HD) patients, mean age, 71±10 years] after excluding 24 patients (lost to follow up and peritoneal dialysis). Follow-up period was 49±24 months. Median DAPT duration was 12 months. The primary endpoint was MACCE. The secondary endpoint was bleeding events according to the Bleeding Academic Research Consortium (BARC) type 2, 3, or 5. MACCE and bleeding events were compared between HD and Non-HD by using the propensity score-matching (PSM) method.

Results

Among the 620 eligible patients, the primary and secondary events occurred in 207 (33.3%) and 76 (12.3%) patients, respectively. The rates of unadjusted MACCE [HD vs Non-HD: 53.9% vs 29.3%; Hazard ratio (HR) 2.39, p<0.01] and bleeding events (HD vs Non-HD: 21.6% vs 10.4%; HR 2.50, p<0.01) were significantly higher in HD than Non-HD.

After 1-to-1 propensity score adjustment for baseline differences (hypertension, diabetes mellitus, low ejection fraction, low albumin, anemia, and high C-reactive protein), a total of 160 patients (80 HD vs 80 Non-HD) was created. The rate of MACCE [HD vs Non-HD: 52.5% vs 31.3%; adjusted HR 2.04, p<0.01] was significantly higher in HD than Non-HD. Regarding MACCE, cardiac death (HD vs Non-HD: 18.8% vs 8.8%; adjusted HR 2.65, p=0.03) and TVR (HD vs Non-HD: 15.0% vs 6.3%; adjusted HR 2.74, p=0.046) occurred significantly higher in HD. On the other hand, bleeding events did not exhibit significant differences though HD had a numerically higher event rate (HD vs Non-HD: 25.0% vs 16.3%; adjusted HR 1.68, p=0.15), indicating that the bleeding risk in HD would be strongly dependent on the patient's background.

Conclusions

As a result of PSM, HD was shown to contribute to ischemic risk rather than bleeding risk. Even in the 2-DES era, HD was an independent risk factor of cardiac death and TVR. Therefore, further study on the current regimen of DAPT would be necessary while balancing both ischemic and bleeding risk.

P3587Tip detection method using the new short-tip IVUS with pull-back system which facilitates the 3D wiring technique in percutaneous coronary intervention for chronic total occlusion

Background

The strategy of intravascular ultrasound (IVUS)-guided wiring for CTO PCI, that is, leading the second guidewire into the true lumen under observing by IVUS from subintimal space, is the last resort. We developed the angiography-based 3D wiring method. During establishment of the angiography-based 3D wiring method, we deduced that observation of the guidewire tip as well as the shaft named “The tip detection method” simplifies and facilitates 3D wiring under IVUS-guided wiring. Therefore, we produced New CTO IVUS which is the upgraded version of Navifocus WR IVUS by adding the pull-back transducer system. This pull-back system enables us to detect the tip as well as the shaft of the second guidewire in real time (tip detection method), which facilitates the 3D wiring technique under IVUS-guided wiring.

Objective

We evaluated the efficacy of the tip detection method during 3D wiring for CTO PCI with New CTO IVUS.

Method

We created a target pinpoint penetration model and performed the procedures using an experimental heartbeat model. The target (a tube with a lumen 0.6 mm in diameter) was placed in the distal part of a CTO 20 mm in length made of 2.5% agar. After the second guidewire (Conquest-12g) was advanced into the CTO lesion to within 5mm of the target using the angiography-based wiring, IVUS-guided wiring was performed by using Navifocus WR or New CTO IVUS each five times.

Result

The frequency of the puncture time was reduced using the new CTO IVUS compared to the Navifocus WR (1.7±0.8 vs. 28.8±23.2, p=0.17). The procedure time was significantly shorter using the new CTO IVUS compared to the Navifocus WR (103±61 vs. 459±373 seconds, p=0.04).

Conclusion

The tip detection method during 3D wiring with the new short tip IVUS with the pull-back system enables us to easily perform 3D wiring and will change the CTO PCI strategy.

P2677A combination of HEART score and a 0-hour/1-hour algorithm for early and safe triage tool for patients in observe zone

Background

The European Society Cardiology guidelines recommend that a 0-hour/1-hour (0–1hr) algorithm using high sensitivity cardiac troponin T (hs-cTnT) improves the early triage of patients with suspected non-ST elevation acute coronary syndrome (NSTE-ACS). However, diagnostic uncertainty remains in the 25–30% of patients assigned to “observe” group.

Purpose

To establish a step wise risk score system using HEART score and 0-hour/1-hour algorithm to identify the low risk group from observation group.

Methods

This study was a prospective, multi-center, observational study of patients with suspected NSTE-ACS admitted to five hospitals in Japan and Taiwan from 2014 to 2018, respectively. We applied the algorithm and calculated HEART score simultaneously. Patients were divided into three groups according to the algorithm: hs-cTnT below 12 ng/L and delta 1 hour below 3 ng/L were the “rule out” group; hs-cTnT at least 52 ng/L or delta 1 hour at least 5 ng/L were in the “rule in” group; the remaining patients were classified as the “observe” group. All patients underwent a clinical assessment the included medical history, physical examination, 12-lead ECG, continuous ECG monitoring, pulse oximetry, standard blood test, chest radiography, cardiac and abdominal ultrasonography. Patients presenting with congestive heart failure, terminal kidney disease on hemodialysis state, arrhythmia, or infection disease (which causes to increase troponin level) were excluded. Thirty-day MACE was defined as acute myocardial infarction, unstable angina (UA), or death.

Results

Of the 1,332 patients enrolled, 933 patients were analyzed after exclusion. NSTE-ACS was the final diagnosis for 122 (13.1%) patients and none of death. The HEART score less than 4 points in observation groups identified as very low risk with a negative predictive value (NPV) of 98.1% (95% confidential interval (CI); 90.1%-100%) and sensitivity of 98.0% (95% CI; 89.6%-100%). There were only one patient (0.5%) with AMI. In case of the HEART score less than 5 points, it could also identify as very low risk with a NPV of 96.7% (95% CI; 90.8%-99.3%%) and sensitivity of 94.1% (95% CI; 83.8%-98.8%). There were only three patients (1.2%) with AMI.

Conclusion

A combination of HEART score and the 0-hour/1-hour algorithm strategy rapidly identified the patient in observation group of 30-day MACE including UA where nor further cardiac testing would be needed.

Acknowledgement/Funding

JSPS KAKENHI Grant Number JP18K09554

P4368Estimation of pulmonary artery pressure from right atrial strain and tricuspid regurgitation velocity

Background

Systolic pulmonary artery pressure (SPAP) can be estimated non-invasively as the sum of indices for right atrial (RA) pressure and tricuspid regurgitation (TR) pressure gradient. Although echocardiographic evaluation of inferior vena cava diameter and collapsibility is currently being used to estimate RA pressure (IVC method), RA strain may be an alternative since atrial strain is related to atrial pressure.

Objective

We tested if RA strain by speckle tracking echocardiography can be used as a surrogate of mean RA pressure (RA strain method), and by adding the TR pressure gradient, be used to estimate SPAP.

Methods

We retrospectively analyzed 91 patients (mean age, 58 years) referred to right heart catheterization due to unexplained dyspnea or suspected pulmonary hypertension. Echocardiography was performed within 24 hours of the invasive procedure. RA reservoir strain was calculated from apical four-chamber view. SPAP was calculated as the sum of peak TR pressure gradient and estimated RA pressure by the IVC or RA strain methods.

Results

Right heart catheterization showed SPAP and mean RA pressures of 51±20 mmHg and 9±6 mmHg, respectively. RA reservoir strain was inversely correlated with mean RA pressure (r=−0.61, p<0.01). Thus, we set mean RA pressure as 5, 10 and 15 mmHg depending on high (≥25%), middle (10–25%) and low (≤10%) values of RA reservoir strain. As shown in the figure, both the RA strain and IVC methods when combined with peak TR velocity, provided good estimates of invasively measured SPAP.

Conclusions

RA strain provides a semiquantitative measure of RA pressure, which can be used in combination with peak TR velocity to estimate SPAP. This approach can be used as an alternative when the IVC method is not available in cases with poor subcostal window.

P1035Factors associated with quality-of-life improvement after catheter ablation of atrial fibrillation: insights from the Kansai Plus Atrial Fibrillation (KPAF) registry

Background

Improving the quality of life (QoL) is one of the main purposes of catheter ablation (CA) of persistent atrial fibrillation (AF). Factors associated with QoL improvement after CA of AF patients have not been clarified. The Kansai Plus Atrial Fibrillation (KPAF) Registry is a multi-center registry enrolling more than 5,000 consecutive patients undergoing the first radiofrequency catheter ablation of AF.

Purpose

The aim of this study was to investigate the QoL change after AF ablation and its associated factors.

Methods

A total of 2030 patients in whom the QoL score was assessed before and one year after the ablation were enrolled from the KPAF registry (age 64±10 years, 75% male, paroxysmal 66%, CHADS2 score 1.1±1.1). The QoL was evaluated using the AF specific QoL evaluation method (AFQLQ), which scores the patient QoL within a range of 0–98 points.

Results

Overall, catheter ablation showed a significant increase in the AFQLQ score (68±19 vs. 86±13 points, P<0.01). AF recurrence was observed in 372 cases (18%) during a 1-year follow-up period. A multivariate analysis showed that AF recurrence, symptomatic AF, long AF duration, high preprocedural heart rate (>110 bpm) and small left atrial diameter were independent predictors of a QoL improvement defined as a >10% score increase.

Multivariate analysis

Conclusions

CA of AF significantly improved the QoL. AF recurrence was one of the strong factors associated with QoL improvement. Symptomatic AF, long AF duration, high preprocedural heart rate and small left atrial diameter were independent predictors of QoL improvement.

P2452Application of left atrial strain for differentiation between pre- and post-capillary pulmonary hypertension

Background

Pulmonary hypertension (PH) is classified as pre- or post-capillary PH, and pulmonary capillary wedge pressure (PCWP) >15 mmHg is used as criterion for post-capillary PH. Elevated left atrial (LA) pressure is associated with reduced LA reservoir strain. Thus, LA strain may potentially serve to differentiate between these diagnoses.

Objectives

This study tested the hypothesis that LA strain can be used as a noninvasive parameter to differentiate between pre- and post-capillary PH.

Methods

We analyzed 103 patients (mean age: 58 years, 51 female) referred to right heart catheterization due to unexplained dyspnea or suspected heart failure. Echocardiography was performed within 24 hours of the invasive procedure. Mean pulmonary artery pressure (PAP) was noninvasively estimated from tricuspid regurgitation (TR) velocity and inferior vena cava (IVC) diameter and collapsibility. LA reservoir strain was calculated from apical four-chamber view by speckle tracking echocardiography, and was feasible in 101 patients.

Results

Twenty-eight patients were invasively confirmed with pre-capillary PH and 43 patients with post-capillary PH. The remaining 32 patients had no PH. LA reservoir strain was significantly lower in patients with post-capillary PH than patients with pre-capillary PH (9.9±5.5% vs. 24.6±8.2%, p<0.01). At a cut-off value of 15.4%, LA reservoir strain could predict elevated PCWP >15 mmHg with AUC=0.88, sensitivity=84.8% and specificity=81.8%. As shown in the figure, echocardiography with LA reservoir strain correctly differentiated 82% of patients into pre- and post-capillary PH.

Conclusions

These results suggest that LA reservoir strain can be used to predict elevated PCWP, thus allowing discrimination between pre- and post-capillary PH.

P1029Catheter ablation outcome and heart failure hospitalization in atrial fibrillation patients: insights from the Kansai plus atrial fibrillation (KPAF) registry

Background

Heart failure (HF) is the leading cause of death in patients with atrial fibrillation (AF). Radiofrequency catheter ablation (RFCA) for AF is effective to maintain sinus rhythm.

Purpose

We sought to clarify whether AF ablation outcome influenced incidence of HF hospitalization after the procedures.

Methods

We conducted a large-scale, prospective, multicenter, observational study. A total of 5010 consecutive patients who underwent an initial RFCA for AF in 26 centers were enrolled (average age, 64±10 years; non-paroxysmal AF, 35.6%). The median follow-up duration was 2.9 years.

Results

The 3-year cumulative incidence of AF recurrence after a single procedure was 40.2%. The 3-year incidence of hospitalization for HF was observed in 92 patients (1.8%) and was significantly higher in patients with AF recurrence than those without it (3.3% vs 0.84%, log-rank p<0.001). After adjustment by advanced age,(≥65 years), reduced left ventricular ejection fraction (≤50%), low estimated glomerular filtration rate (≤60ml/min), and history of HF, all of which were statistically associated with a risk of HF hospitalization (p<0.1, respectively), AF recurrence after the index RFCA was an independent predictor of HF hospitalization (hazard ratio [HR]; 3.17, 95% confidence interval [CI]; 2.06–5.04, p<0.001).Even after multiple procedures (1425 re-ablation sessions in 1274 patients [25.4%]), AF recurrence after the last procedure was an independent predictor of HF hospitalization (HR; 2.83, 95% CI; 1.89–4.24, p<0.001).

Conclusions

Among AF patients receiving RFCA, those with AF recurrence were at greater risk of heart failure hospitalization than were patients without AF recurrence. These differences should be noted when treating AF patients in actual clinical practice.

Acknowledgement/Funding

This study was supported by the Research Institute for Production Development in Kyoto, Japan.

P2676Prospective validation of the 2015 ESC 0-hour/1-hour algorithm using high-sensitivity cardiac troponin T in Asian countries

Background/Introduction

Implementation of the 2015 ESC 0-hour/1-hour algorithm using high-sensitivity troponin (hs-cTn) T in Asian countries presents a challenge for clinical practice.

Purpose

We aimed to prospectively validate the 0-hour/1-hour algorithm in Asian countries.

Methods

We conducted a prospective, multi-center, international cohort already utilizing 0-hour/1-hour algorithm using hs-cTnT for evaluation of patients with suspected of non-ST elevation acute coronary syndrome (NSTE-ACS). All patients underwent a clinical assessment the included medical history, physical examination, 12-lead ECG, continuous ECG monitoring, pulse oximetry, standard blood test, chest radiography, cardiac and abdominal ultrasonography. Patients presenting with congestive heart failure, terminal kidney disease on hemodialysis state, arrhythmia, or infection disease (which cause to increase troponin level) were excluded. Patients were divided into three groups according to the algorithm: hs-cTnT below 12 ng/L and delta 1 hour below 3 ng/L were the “rule out” group; hs-cTnT at least 52 ng/L or delta 1 hour at least 5 ng/L were in the “rule in” group; the remaining patients were classified as the “observational” group. The final diagnosis was then adjudicated by 2 independent cardiologists using all available information, including coronary angiography, coronary computed tomography, stress electrocardiography and follow-up data. The presence of acute myocardial infarction (AMI) was defined according to the Fourth Universal Definition of Myocardial Infarction.

Results

Of the 1,332 patients enrolled in 2014 to 2018, 933 patients were analyzed after exclusion. AMI was the final diagnosis for 122 (13.1%) patients. The algorithm ruled out AMI in 401 patients with a negative predictive value and sensitivity of 100% (95% confidential interval [CI], 98.6%-100%) and 100% (95% CI, 94.0%-100%), respectively, in the rule-out group. None of the patients were diagnosed with AMI. Among the 211 patients classified into the rule-in group, 90 were diagnosed as having AMI. The positive predictive value and specificity were 43.1% (95% CI, 36.2%-50.2%) and 78.3% (95% CI, 74.5%-81.7%), respectively. The median length of hospital stay was 159 min (142–180) in rule out group.

Conclusion(s)

Our findings suggest that the 0-hour/1-hour algorithm using hs-cTnT provides very high safety and efficacy for the triage toward rapid rule-out to rule-in of AMI.

Acknowledgement/Funding

JSPS KAKENHI Grant Number JP18K09554

P5650Improvement in ejection fraction predicts heart failure after catheter ablation for atrial fibrillation in patients with left ventricular systolic dysfunction: from the KPAF registry

Introduction

The presence of atrial fibrillation (AF) in patients with reduced left ventricular ejection fraction (LVEF) is associated with increased risks of mortality and hospitalization for heart failure (HF). Although prior studies reported that catheter ablation (CA) for AF in low LVEF patients reduced risks of all-cause mortality and HF hospitalization, the predictors of worsening HF after ablation has not been adequately evaluated.

Purpose

The purpose of this study was to investigate the impact of improvement in LVEF after AF ablation on the incidence of subsequent HF hospitalization in patients with low LVEF.

Methods

The Kansai Plus Atrial Fibrillation (KPAF) Registry is a multicenter registry enrolling 5,013 consecutive patients undergoing first-time ablation for AF. The current study population consisted of 1,031 patients with reduced LVEF of <60%. We divided the study population into 3 groups according to LVEF at follow-up; 678 patients (65.8%) with improved LVEF (≥5 U change in LVEF), 288 patients (27.9%) with unchanged LVEF (−5 U ≤ change in LVEF <5 U) and 65 patients (6.3%) with worsened LVEF (<−5 U change in LVEF).

Results

During the median follow-up of 1067 [879–1226] days, patients improved LVEF had lower rate of HF hospitalization, compared with those with unchanged and worsened LVEF (2.1%, 8.0%, and 21.5%, respectively, P<0.0001). Recurrent atrial tachyarrhythmias were documented in 43.5%, 47.2% and 67.7%, respectively (P=0.0008).

Figure 1

Conclusion

Among patients with reduced LVEF undergoing AF ablation, patients with subsequently improved LVEF in association with maintained sinus rhythm had markedly lower risk of HF hospitalization during follow-up as compared with those with unchanged or worsened LVEF.

FEASIBILITY STUDY ON THE FUSION OF PHITS SIMULATIONS AND THE DLNN ALGORITHM FOR A NEW QUANTITATIVE METHOD OF IN-SITU MULTIPLE-CHANNEL DEPTH DISTRIBUTION SPECTROMETRY

We have recently have developed an in-situ multiple-channel depth distribution spectrometer (DDS) that can easily acquire on-site measurements of the depth distribution of specific radioactivities of Cs-134 and Cs-137 underground. Despite considerable improvements in the hardware developed for this device, the quantitative method for determining of radioactivities with this DDS device cannot yet achieve satisfactory performance for practical use. For example, this method cannot discriminate each γ-ray spectra of Cs-134 and Cs-137 acquired by the 20 thallium-doped caesium iodine CsI(Tl) scintillation crystal detectors of the DDS device from corresponding depth levels of underground soil. Therefore, we have applied deep learning neural network (DLNN) as a novel radiation measurement technique to discriminate the spectra and to determine the specific radioactivities of Cs-134 and Cs-137. We have developed model soil layers on a virtual space in Monte-Carlo based PHITS simulations and transported γ-ray radiation generated from a particular single soil layer or multiple layers as radiation sources; next, we performed PHITS calculations of those specific radioactivity measurements for each soil layer using DDS device based on machine learning via the DLNN algorithm. In this study, we obtained informative results regarding the feasibility of the proposal innovative radiation measurement method for further practical use in on-site applications.

NATURAL RADIOACTIVITY MEASUREMENT AND DOSE ASSESSMENT OF BEACH PLACER SANDS IN THE COASTAL REGION OF TAMIL NADU (INDIA)

A preliminary study was carried out to determine the radioactivity concentration of 232Th, 226Ra and 40K in beach placer sands from 13 locations along the coast line of Tamil Nadu state, India. The ambient dose rates varied from 9 to 467 nGy h-1. The activity concentrations of radionuclide 232Th, 226Ra and 40K ranged from 5.2 to 683 Bq kg-1, 13 to 198 Bq kg-1 and 107 to 421 Bq kg-1, respectively. The annual effective dose rate ranges from 27 to 620 μSv y-1 and was higher at seven beaches in comparison to the UNSCEAR annual worldwide average value.

P3590Impact of right ventricular branch slow flow phenomenon post percutaneous coronary intervention for acute coronary syndrome to predict sustained right ventricular dysfunction

Background

Although Right Ventricular dysfunction (RVD) is one of the predictor of poor prognosis, it is believed that ischemic RVD after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) restores quickly. Because right ventricular perfusion has more ischemic preconditioning compared with left ventricle, due to their complex perfusion system. However, little is known about the time courses of RVD after ACS-PCI andtheir prognosis. We evaluated the relationship between right ventricular branch slow flow phenomenon (RVB-SF) post ACS-PCI in right coronary artery (RCA) and RVD at 6–8 months follow-up.

Method

We retrospectively analyzed consecutive 82 patients who underwent PCI for ACS in proximal or mid portion of RCA from August 2011 to March 2018 in our institution. Finally, both baseline and follow-up data were obtained from 70 patients. We analyzed TIMI frame count (TFC) to confirm the presence of RVB-SF (TFC ≥40 frame) after PCI. We also analyzed right ventricular fractional area change (RVFAC) at baseline and follow-up using echocardiography to detect sustained RVD (RVFAC ≤35%).

Result

We divided the patients into two groups (RVB-SF: 36 patients, RVB non-SF: 34 patients). Patient clinical characteristics were similar in both groups (sex, age, risk factors, medication, onset to balloon time, left ventricular stroke volume, max creatine kinase). Baseline RVFAC and follow-up RVFAC was significantly smaller in RVB-SF than in RVB non-SF, respectively. (27.1±1.7% vs. 38.3±1.8%, 31.4±1.0% vs. 48.7±1.1%, P<0.0001). However, ΔRVFAC (follow-up RVFAC – baseline RVFAC) was similar between groups. The size of inferior vena cava and systolic pulmonary artery pressure at follow-up were similar in both groups (12.1±0.6 mm vs. 11.7±0.7 mm, P=0.67, 25.7±1.5 mmHg vs. 25.2±1.5 mmHg, P=0.82). In RVB non-SF, 10 patients (29.4%) were diagnosed clinical RVAMI. However, follow-up RVFAC were similar and preserved in both groups (RVAMI: 48.1±1.3%, non-RVAMI: 49.9±1.9%, P=0.85). In RVB-SF, 19 patients (52.7%) were diagnosed clinical RVAMI. Follow-up RVFAC did not improved significantly in both groups (RVAMI: 30.4±1.4% vs. non-RVAMI: 32.6±1.5%, P=0.70). Multivariate analysis showed RVB-SF was the only independent predictor of sustained RVD at 6–8 months follow-up after ACS-PCI.

Conclusion

RVB-SF findings after ACS-PCI for RCA could predict sustained RVD at mid-term follow-up, which may indicate future prolonged RVD.

P1038Device implantation after catheter ablation of paroxysmal atrial fibrillation with coexisting sick sinus syndrome: Insights from the Kansai Plus Atrial Fibrillation (KPAF) study

Background

Sick sinus syndrome (SSS) and atrial fibrillation (AF) frequently coexist and interact to initiate and perpetuate each other. Several retrospective or small cohort studies have suggested that successful catheter ablation of AF may help to waive device implantations in patients with paroxysmal AF plus SSS, however, no prospective large studies are so far available on this scenario.

Purpose

We aimed to elucidate the device implantation-free survival after catheter ablation of paroxysmal AF with coexisting SSS in a prospective large-scale registry. We also determined the risk factors for device implantations after catheter ablation of paroxysmal AF.

Methods

The Kansai Plus Atrial Fibrillation (KPAF) study is a multi-center prospective registry that enrolled 5,019 consecutive patients that underwent an initial pulmonary vein isolation-based radiofrequency catheter ablation of AF. This study was comprised of 3,226 patients with paroxysmal AF registered in the KPAF study (age, 64.8±10.5 years old; female, n=999 [31.0%]; left atrial diameter [LAD], 37.5±8.0 mm; left ventricular ejection fraction [LVEF], 65.3±8.4%, CHADS2 score, 1.09±1.05). The atrial tachyarrhythmia-free and device-free survivals after catheter ablation were compared between patients with SSS (n=368; tachy-brady syndrome, 88%) and without SSS (control; n=2,858).

Results

The atrial tachyarrhythmia-free survival was almost identical between the two groups both after the first ablation session (Fig.1A) and after the last procedure with an average of 1.3±0.5 sessions. At baseline, the devices had already been implanted in 53 (14.4%) SSS and 36 (1.3%) control patients. In the remaining patients, devices were newly implanted in 54 (17.1%) SSS and 62 (2.2%) control patients during the follow-up of 3 years after the catheter ablation (Figure 1B). In the SSS group, devices were implanted predominantly within 6 months after the catheter ablation, and atrial tachyarrhythmia recurrence preceded the device implantation in 48 (89%) patients. Multivariate predictors of device implantations after the paroxysmal AF ablation included: SSS (hazard ratio [HR] 6.85, 95% confidence interval [CI] 4.61–10.19, p<0.001), an age>75 years old (HR 1.69, 95% CI 1.08–2.64, p=0.019), a female gender (HR 2.16, 95% CI 1.44–3.24, p<0.001), the LAD (mm) (HR 1.05, 95% CI 1.02–1.08, p=0.006), and the LVEF (%) (95% CI 0.96, 95% CI 0.94–0.98, p<0.001).

Figure 1

Conclusions

Device implantations could be waived in >80% of patients with SSS at 3 years of follow-up after the catheter ablation of paroxysmal AF in this real world all comer prospective registry. In addition to coexisting SSS, predictors of device implantations after paroxysmal AF ablation included: the elderly, a female gender, a large LA, and a reduced LVEF.

Acknowledgement/Funding

None

P2458Restricted left atrial motion as a result of atrial stiffening in patients with cardiac amyloidosis

Background

Left atrial (LA) involvement of abnormal amyloid fibrils could induce LA dysfunction and stiffening in patients with cardiac amyloidosis (CA). Thus, the assessments of LA function and stiffness might be a potential approach to diagnose CA phenotype among patients with hypertrophied hearts.

Purpose

We sought to determine whether LA reservoir strain with speckle tracking echocardiography could be used a marker of LA stiffness in a derivation cohort. Furthermore, we tested to our hypothesis that LA reservoir strain could differentiate CA patients from hypertrophic cardiomyopathy (HCM) in an independent validation cohort.

Methods

In the derivation cohort, echocardiography was performed simultaneously with measurements of pulmonary capillary wedge pressure (PCWP) in 50 patients with suspected or established heart failure and relatively preserved left ventricular (LV) ejection fraction (56±10%). LA maximum and minimum volume index, and reservoir strain were measured from apical four-chamber view. LA stiffness index was computed as a pressure rise from x-trough to v-wave divided by an increase from minimum to maximum indexed LA volume (Figure A). In an independent validation group, we studied a total of 33 biopsy-proved CA patients and 127 HCM patients (LV ejection fraction: 57±11% vs. 66±10%, P<0.01) in sinus rhythm on the date of comprehensive echocardiographic study. Among them, cardiac magnetic resonance imaging (CMR) could be evaluated in 17 CA patients and 98 HCM patients. Furthermore, right heart catheterization was performed with 12 CA patients and 12 HCM patients in the CMR group.

Results

The derivation cohort study found that there was a significant curvilinear correlation of LA reservoir strain to LA stiffness index (Figure B). In the validation cohort, LA reservoir strain was reduced in patients with CA compared with HCM in all participants (11.6±5.6% vs. 18.5±6.9%, P<0.01), although there was no significant difference of LA maximal volume index between 2 groups (37±16 ml/m2 vs. 37±12 ml/m2, p=0.89). In the CMR group, the late gadolinium enhancement was observed in the LA wall in 16 patients with CA (94.1%) as shown in Figure C. In contrast, the LA enhancement revealed only in 1 patient with HCM (1.0%). Among patients with invasive measures, LA stiffness index [median (interquartile range)] was higher in patients with CA than that in patients with HCM [1.1 (0.4–2.8) vs. 0.2 (0.1–0.6), P=0.01].

Conclusions

LA reservoir function was fairly limited in patients with CA compared with HCM. Restricted LA motion might be related to atrial amyloid deposits or fibrosis, which potentially provokes atrial chamber stiffening.

P1865Incidence and predictors of invasively-treated pericardial effusion during catheter ablation of atrial fibrillation in Japan

Purpose and method

Japanese Heart Rhythm Society requested electrophysiology centers to register the data of patients who underwent catheter ablation for atrial fibrillation (AF) in designated eight months from 2011 to 2017. We assessed the incidence and predictors of pericardial effusion (PE) as an early complication of AF ablation.

Results

More than two hundred EP centers reported the data of 13,233 AF ablation cases (age; 64.2±10.7 years, male; 72.6%, paroxysmal AF; 63.4%). Clinically significant complications occurred in 601 subjects (4.5%). Critical PE occurred in 116 patients (0.8%), while six of them required open-chest surgery. Overall complication rate did not show significant changes. In contrast, incidence of PE declined over time (2012:1.2%, 2017:0.5%, p=0.003). Multiple logistic regression analysis showed that seven factors were related with higher incidence of PE. Among these factors, primary extra-PV ablation and hypertrophic cardiomyopathy (HCM) were more remarkably associated with higher rate of PE (PVI[−] vs. PVI[+]= 9.0% vs. 0.8%, OR 12.3, p<0.001; HCM: [+] vs. [−] = 2.6% vs. 0.8%, OR 3.26, p=0.001). Comorbidity of coronary artery disease (CAD) and use of CARTO system were related with lower PE rate (CAD: [+] vs [−] = 0.2% vs. 0.9%, OR 0.22 [p=0.034], CARTO: [+] vs [−] = 0.7% vs. 1.2%, OR 0.52 [p=0.001]). None of cryobaloon ablation, gender, type of AF, center volume, periprocedural oral anticoagulant, or left atrial diameter was significantly related with the occurrence of PE.

Conclusions

Incidence of critical PE decreased recently. HCM and primary extra-PV ablation were outstanding predictors of critical PE.

P980Post-procedural plasma brain natriuretic peptide level early after catheter ablation predicts the future clinical outcome in patients with persistent atrial fibrillation and reduced ejection fraction

Background

Successful restoration of sinus rhythm (SR) by catheter ablation (CA) for persistent atrial fibrillation (AF) improves cardiac function, resulting in decrease of plasma brain natriuretic peptide (BNP) level. The exact significance and prognostic implications of this change have yet to be determined.

Purpose

To examine the impact of pre- and post-procedural BNP level on the clinical outcome after CA in patients with persistent AF and reduced left ventricular ejection fraction (LVEF).

Methods

Out of 242 patients with LVEF <50% who underwent first-time CA for persistent AF between March 2012 and September 2018 at our institute, we enrolled 137 patients (61±10 years, 83% male) whose plasma BNP level was available both at baseline and early after CA (during 1–3 month). We evaluated the impact of the BNP levels on future AF recurrence 3 months after CA as the primary endpoint. Additional secondary endpoints included heart failure (HF) hospitalization and cardiovascular death.

Results

All patients successfully restored SR at the end of CA. Within 3 months of a blanking period (BP), improvement of LVEF (from 39±10% to 65±12%, p<0.001) and reduction of BNP levels (from 178 [107–332] pg/ml to 42.3 [21.1–78.6] pg/ml, p<0.001) were observed. During the median follow-up of 21 months after BP, the incidence of AF recurrence, HF hospitalization, and cardiovascular death was 37% (n=50), 3% (n=4), and 1% (n=1), respectively. Cox proportional hazard regression analysis after adjustment for age and gender revealed that post-procedural BNP level was a significant predictor of the AF recurrence (hazard ratio [HR] per 100-pg/ml increase, 1.13; 95% confidence interval [CI], 1.02–1.25; p=0.023), but pre-procedural BNP level was not (1.02; 0.95–1.09; p=0.56). Receiver operating curve analysis determined the post-procedural BNP level of 55.5 pg/ml as the best cut-off value for predicting the AF recurrence, with area under the curve of 0.620 (95% CI, 0.534–0.702; p=0.018). The incidence of AF recurrence was significantly higher in patients with post-procedural BNP level >55.5 pg/ml (n=50) than the others (50% vs. 29%; HR, 3.99; 95% CI, 2.07–7.68; p<0.001). No patients with post-procedural BNP level ≤55.5 pg/ml experienced HF hospitalization and cardiovascular death (8% vs. 0% and 2% vs. 0%, p=0.006 and p=0.17, respectively)

Conclusions

Not pre-procedural but post-procedural BNP level early after CA predicted the future clinical outcome in patients with persistent AF and reduced LVEF. Decreased but still elevated BNP level after restoration of SR would identify the residual risk for developing unfavorable outcome.

IMPACT ON ABSORBED DOSE RATE IN AIR IN KANTO REGION BY FUKUSHIMA DAIICHI NUCLEAR POWER PLANT ACCIDENT

Absorbed dose rates in air were measured for the whole area of the Kanto region in 2015, 2016 and 2017 (n = 31 147). The mean absorbed dose rates in air for each prefecture measured by car-borne surveys were from 44 to 67 nGy h-1 (13-289 nGy h-1). The absorbed dose rate in air from artificial radionuclides (134Cs + 137Cs) measured by fixed-point observation (n = 507) was from 1 to 14 nGy h-1 (0-105 nGy h-1), and meaning that the contribution ratios of 134Cs and 137Cs were 3-22%. The deposited location of artificial radionuclides was less than 1000 m from ground level and depended on the topography, wind direction and precipitation field.

Dysfunction of Poly (ADP-Ribose) Glycohydrolase Induces a Synthetic Lethal Effect in Dual Specificity Phosphatase 22-Deficient Lung Cancer Cells

Poly (ADP-ribose) glycohydrolase (PARG) is the main enzyme responsible for catabolism of poly (ADP-ribose) (PAR), synthesized by PARP. PARG dysfunction sensitizes certain cancer cells to alkylating agents and cisplatin by perturbing the DNA damage response. The gene mutations that sensitize cancer cells to PARG dysfunction-induced death remain to be identified. Here, we performed a comprehensive analysis of synthetic lethal genes using inducible PARG knockdown cells and identified dual specificity phosphatase 22 (DUSP22) as a novel synthetic lethal gene related to PARG dysfunction. DUSP22 is considered a tumor suppressor and its mutation has been frequently reported in lung, colon, and other tumors. In the absence of DNA damage, dual depletion of PARG and DUSP22 in HeLa and lung cancer A549 cells reduced survival compared with single-knockdown counterparts. Dual depletion of PARG and DUSP22 increased the apoptotic sub-G₁ fraction and upregulated PUMA in lung cancer A549, PC14, and SBC5 cells, and inhibited the PI3K/AKT/mTOR pathway in A549 cells, suggesting that dual depletion of PARG and DUSP22 induced apoptosis by upregulating PUMA and suppressing the PI3K/AKT/mTOR pathway. Consistently, the growth of tumors derived from double knockdown A549 cells was slower compared with those derived from control siRNA-transfected cells. Taken together, these results indicate that DUSP22 deficiency exerts a synthetic lethal effect when combined with PARG dysfunction, suggesting that DUSP22 dysfunction could be a useful biomarker for cancer therapy using PARG inhibitors. SIGNIFICANCE: This study identified DUSP22 as a novel synthetic lethal gene under the condition of PARG dysfunction and elucidated the mechanism of synthetic lethality in lung cancer cells.

Precision Analysis of the ^{136}Xe Two-Neutrino ββ Spectrum in KamLAND-Zen and Its Impact on the Quenching of Nuclear Matrix Elements

We present a precision analysis of the ^{136}Xe two-neutrino ββ electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ββ rate allows us to measure the ratio of the leading and subleading 2νββ nuclear matrix elements (NMEs), ξ_{31}^{2ν}=-0.26_{-0.25}^{+0.31}. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ξ_{31}^{2ν} range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ξ_{31}^{2ν} values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ββ decay, ξ_{31}^{2ν} provides new insights toward reliable neutrinoless ββ NMEs.

Serum cell-free DNA levels are a useful marker for extramammary Paget disease

BACKGROUND

Although carcinoembryonic antigen (CEA) and cytokeratin 19 fragment (CYFRA) are useful markers for extramammary Paget disease (EMPD), serum CEA and CYFRA levels are not elevated in most patients with EMPD without metastasis. Cell-free (cf)DNA has attracted attention as an indicator of clinical conditions in several cancers.

OBJECTIVES

To identify further useful biomarkers for the detection of EMPD, including early lesions, and to study the clinical implications of cfDNA in EMPD.

METHODS

cfDNA were isolated from serum of patients with EMPD with and without metastasis, and from healthy volunteers. Serum extracts were amplified using polymerase chain reaction.

RESULTS

Serum cfDNA levels were significantly elevated in patients with EMPD with or without metastasis compared with those in healthy controls. Serum cfDNA was a better diagnostic marker for the presence of EMPD than serum CYFRA. Moreover, the postoperative serum cfDNA levels were significantly lower than those from the preoperative samples, and the change in serum cfDNA levels reflected the clinical courses of patients with EMPD treated with chemotherapy.

CONCLUSIONS

Taking the evidence together, serum cfDNA levels may be a useful marker for diagnosis and disease progression in EMPD. What's already known about this topic? Serum levels of carcinoembryonic antigen (CEA) and cytokeratin 19 fragment (CYFRA) are not elevated in most patients with extramammary Paget disease (EMPD) without metastasis. Cell-free (cf)DNA has attracted attention as an indicator of clinical conditions in several cancers. There are few reports of the clinical implications of cfDNA in dermatology. What does this study add? Serum cfDNA levels were significantly elevated in patients with EMPD with or without metastasis compared with those in healthy controls. Postoperative serum cfDNA levels were significantly lower than those from the preoperative samples. Changes in serum cfDNA levels reflected the clinical courses of patients with EMPD treated with chemotherapy. What is the translational message? Serum cfDNA levels in patients with EMPD are a useful marker for the detection of EMPD, including localized EMPD. Changes in serum cfDNA levels in an individual patient may reflect the clinical course of EMPD.