Tip Detection-Antegrade Dissection and Re-Entry With New Puncture Wire in CTO Intervention: Revolution Through 3D-Wiring

Background

The authors devised the tip detection (TD) method and developed AnteOwl WR intravascular ultrasound to standardize intravascular ultrasound-based 3-dimensional wiring for intraplaque tracking in chronic total occlusion (CTO)-percutaneous coronary intervention (PCI). The TD method also allowed antegrade dissection and re-entry (ADR). Combining TD-ADR with Conquest Pro 12 Sharpened Tip (CP12ST) wire, a new ADR wire with the strongest penetration force developed to date, enabled re-entry anywhere except calcification sites.

Objectives

This study investigated the efficacy and feasibility of TD-ADR by comparison of procedural outcomes with Stingray-ADR in CTO-PCI.

Methods

Twenty-seven consecutive CTO cases treated by TD-ADR with CP12ST wire between August 2021 and April 2023 and 27 consecutive CTO cases treated by Stingray-ADR with Conquest 8-20 (CP20) wire between March 2018 and July 2021 were retrospectively enrolled as the TD-ADR by CP12ST wire group and Stingray-ADR by CP20 wire group, respectively, from 4 facilities that could share technical information on these procedures.

Results

The success rate of the ADR procedure was significantly improved (27 of 27 cases [100%] vs 18 of 27 cases [67%], respectively; P = 0.002) and total procedural time was significantly reduced (median procedural time: 145.0 [Q1-Q3: 118.0-240.0] minutes vs 185.0 [Q1-Q3: 159.5-248.0] minutes, respectively; P = 0.028) in the TD-ADR by CP12ST wire group compared to the Stingray-ADR by CP20 wire group. There were few in-hospital major adverse cardiac and cerebrovascular events or no complications in either group.

Conclusions

TD-ADR by CP12ST wire can standardize highly accurate ADR in CTO-PCI.

The WATCH-DM risk score estimates clinical outcomes in type 2 diabetic patients with heart failure with preserved ejection fraction

The coexistence of heart failure is frequent and associated with higher mortality in patients with type 2 diabetes (T2DM), and its management is a critical issue. The WATCH-DM risk score is a tool to predict heart failure in patients with type 2 diabetes mellitus (T2DM). We investigated whether it could estimate outcomes in T2DM patients with heart failure with preserved ejection fraction (HFpEF). The WATCH-DM risk score was calculated in 418 patients with T2DM hospitalized for HFpEF (male 49.5%, age 80 ± 9 years, HbA1c 6.8 ± 1.0%), and they were divided into the "average or lower" (≤ 10 points), "high" (11-13 points) and "very high" (≥ 14 points) risk groups. We followed patients to observe all-cause death for 386 days (median). We compared the area under the curve (AUC) of the WATCH-DM score for predicting 1-year mortality with that of the Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) score and of the Barcelona Bio-Heart Failure Risk (BCN Bio-HF). Among the study patients, 108 patients (25.8%) had average or lower risk scores, 147 patients (35.2%) had high risk scores, and 163 patients (39.0%) had very high risk scores. The Cox proportional hazard model selected the WATCH-DM score as an independent predictor of all-cause death (HR per unit 1.10, 95% CI 1.03 to 1.19), and the "average or lower" risk group had lower mortality than the other groups (p = 0.047 by log-rank test). The AUC of the WATCH-DM for 1-year mortality was 0.64 (95% CI 0.45 to 0.74), which was not different from that of the MAGGIC score (0.72, 95% CI 0.63 to 0.80, p = 0.08) or that of BCN Bio-HF (0.70, 0.61 to 0.80, p = 0.25). The WATCH-DM risk score can estimate prognosis in T2DM patients with HFpEF and can identify patients at higher risk of mortality.

Influence of ultrasound transmit frequency on measurement of global longitudinal strain on 2D speckle tracking echocardiography

The reproducibility of longitudinal strain measured by 2D speckle tracking echocardiography (2DSTE) may be affected by ultrasound settings. This study investigated the effect of transmit ultrasound frequency on global longitudinal strain (GLS) by 2DSTE. Apical, 2- and 4-chamber, and long-axis views were obtained in consecutive 162 patients using Philips ultrasound devices. Three different frequency presets were used sequentially: high resolution (HRES, 1.9 to 2.1 MHz), general (HGEN, 1.6 to 1.8 MHz), and penetration mode (HPEN, 1.3 to 1.6 MHz). GLS values were determined for each preset using the Philips Q-station software, resulting in GLS-HRES, GLS-HGEN, and GLS-HPEN. Among the 151 patients with successfully measured GLS, a significant difference in GLS was observed among the three presets (p < 0.0001). GLS-HRES (- 17.9 ± 4.4%) showed a slightly smaller magnitude compared to GLS-HGEN (- 18.8 ± 4.5%, p < 0.0001) and GLS-HPEN (- 18.8 ± 4.5%, p < 0.0001), with absolute differences of 1.1 ± 1.0% and 1.1 ± 1.2%, respectively. This variation in GLS with frequency was evident in patients with both optimal (n = 104) and suboptimal (n = 47) image quality and remained consistent regardless of ultrasound devices, ischemic etiology, or ejection fraction. In conclusion, ultrasound frequency had only a modest effect on GLS measurements. GLS may be reliably assessed in most cases regardless of the ultrasound frequency used.

Guide extension proximal locking method: standardization of maximum backup force in percutaneous coronary intervention

We developed the smallest diameter guide-extension catheter (GUIDE PLUS® 5Fr) to enable a new technique, the guide-extension proximal locking method (GP-Lock), and assessed its efficacy in the present experimental and clinical study. Sufficient guide catheter backup is sometimes crucial for PCI. We developed the KIWAMI-Lock direct anchoring method to obtain the strongest backup force by locking a Kiwami® 4Fr child catheter (Terumo Corp. Tokyo, Japan) directly to the coronary artery by ballooning from outside the child catheter. However, this method is complicated due to the requirement for a child catheter. We compared the backup power of the GP-Lock method and other conventional methods in an experimental study and compared the procedural outcomes of 17 cases treated using the initial GP-Lock method with 17 cases using the recent KIWAMI-Lock method before GP-Lock. The GP-Lock method had the highest backup force among the methods examined (GP-Lock: 293.7 ± 10.2 g force (gf), KIWAMI-Lock: 270.4 ± 12.9 gf, side branch balloon anchoring technique: 182.7 ± 8.1 gf, respectively, P < 0.0001). The preparation time was significantly shorter for the GP-Lock group than the KIWAMI-Lock group (5.0 [4.0, 5.0] min vs. 11.0 [8.0, 13.0] min, respectively, P < 0.001). The GP-Lock method makes it possible to easily obtain the strongest backup force, which can overcome situations where devices cannot pass through, especially in complex PCI procedures.

PI3K/mTOR Inhibitor Dactolisib Attenuates Allergic Response Through Inhibitions of the Sensitization and Mast Cell Activation

The aim of this study was to evaluate the anti-allergic potentials of dactolisib, a dual PI3K/mTOR kinase inhibitor, on two important events for allergy: sensitization and the onset of anaphylactic symptoms. After sensitization with the antigen ovalbumin (OVA), five successive oral administrations of dactolisib effectively decreased serum anti-OVA antibody-an indicator of sensitization-levels in mice. In parallel with the antibody levels in their serum, anaphylactic rectal temperature decrease induced by the re-administration of OVA to dactolisib-treated mice was strongly diminished compared to that in vehicle-treated mice. The inhibitor also inhibited ex vivo splenic B cell activation indicated by the increase of phosphorylation of Akt, CD69 expression levels, and proliferation upon anti-B cell receptor antibody treatment, suggesting that suppressive effects of the inhibitor on B cell activation plays a role in its ability to decrease sensitization in vivo. We concurrently observed the anti-anaphylactic ability of dactolisib in vivoand in vitro. A single oral administration of the inhibitor attenuated the anaphylactic rectal temperature decrease induced in a mouse model of passive systemic anaphylaxis. In in vitro mast cell models, pretreatment with the drug inhibited the degranulation response and cytokine production in RBL2H3 cells triggered by IgE and antigens, without affecting cell viability. These results suggest that dactolisib, as well as other PI3K/mTOR inhibitors, might be a good candidate for anti-allergic drugs that exhibit both anti-sensitizing and anti-anaphylactic effects.

Sleep apnea severity in patients undergoing atrial fibrillation ablation: Home sleep apnea-test and polysomnography comparison

BACKGROUND

Sleep apnea (SA) is highly prevalent and should be treated in patients referred for catheter ablation (CA) of atrial fibrillation (AF). Watch-type peripheral arterial tonometry (WP) for home SA testing has demonstrated a high correlation of the apnea-hypopnea index (AHI) with Polysomnography (PSG), but the evidence of its accuracy in AF patients is not adequate.

METHODS

This study was conducted under a retrospective, single-center, observational design. We included 464 consecutive AF patients (age 65 ± 11 years, 76.5% male, 45.0% paroxysmal-AF) who received both WP and PSG during the periprocedural period of the CA. We compared the AHI using the WP (WP-AHI) to that using PSG (PSG-AHI).

RESULTS

The WP-AHI was 25.9 ± 12.7 and PSG-AHI 31.4 ± 18.9 (r = .48). Among 325 patients with a WP-AHI < 30, 116 (35.7%) exhibited a PSG-AHI ≥ 30. Only 12.5% of the patients were indicated for continuous positive airway pressure (CPAP) treatment only by the WP-AHI, while 70.9% were indicated for CPAP by the PSG-AHI according to the Japanese health insurance system. The best cut-off value of the WP-AHI was 18.1 to predict a PSG-AHI ≥ 20 with an area under the curve of 0.72 (95% confidence interval, 0.67-0.76).

CONCLUSIONS

The WP-AHI and PSG-AHI were weakly correlated in AF patients receiving CA. About one-third of the patients with moderate SA using the WP was diagnosed with severe SA evaluated by PSG. The majority required PSG for the CPAP indication.

Impact of Residual Functional Mitral Regurgitation After Atrial Fibrillation Ablation on Clinical Outcomes in Patients With Left Ventricular Systolic Dysfunction

Functional mitral regurgitation (FMR) negatively impacts the prognosis in patients with atrial fibrillation (AF) and reduced left ventricular (LV) ejection fraction (LVEF). Although structural reverse remodeling after AF ablation can reduce FMR severity, the prognostic impact of FMR and its evolution remain unclear. Of 491 patients with baseline LVEF <50% who underwent first-time AF ablation, 134 patients (27%) had grade 2 to 4 FMR at baseline. Among them, 88 patients (66%) exhibited FMR improvement to grade 0 to 1 FMR 6 months after AF ablation. Conversely, among 357 with baseline grade 0 to 1 FMR, 13 patients (3.6%) exhibited FMR worsening to grade 2 to 4 FMR despite AF ablation. Assessment with multidetector computed tomography revealed that an increase in the left atrial emptying fraction (odds ratio 3.55 per 10% increase; 95% confidence interval 2.12 to 5.95) and a reduction in the LV end-diastolic volume index (1.35 per 10-ml/m² decrease; 1.04 to 1.76) were identified as contributors to the FMR improvement. During a follow-up of 43 months, patients with postprocedural grade 2 to 4 FMR more frequently experienced hospitalizations for heart failure or cardiovascular death than those with grade 0 to 1 FMR (30.5% vs 4.6%, log-rank p <0.001). An age-adjusted multivariate Cox regression analysis including baseline and postprocedural FMR revealed that postprocedural grade 2 to 4 FMR (hazard ratio, 3.24; 95% confidence interval 1.43 to 7.35) was significantly associated with unfavorable events. In conclusion, AF ablation modified and often improved FMR severity in patients with reduced LVEF. Residual grade 2 to 4 FMR 6 months after AF ablation was associated with a poor prognosis.

Atrial Fibrillation Ablation Outcomes and Heart Failure (from the Kansai Plus Atrial Fibrillation Registry)

The impact of rhythm outcomes on heart failure (HF) hospitalizations remains unknown after radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). We sought to elucidate whether AF recurrence was associated with HF hospitalizations after AF RFCA. We conducted a large-scale, prospective, multicenter, observational study (Kansai Plus Atrial Fibrillation Registry), enrolling 5,010 consecutive patients (age 64 ± 10 years, 27.3% female, and 35.7% nonparoxysmal AF) who underwent an initial AF RFCA at 26 centers. The median follow-up duration was 2.9 years. The cumulative 3-year incidence of HF hospitalizations after the initial RFCA was 1.84% (0.69%/year). Hospitalized patients with HF were older with a higher prevalence of nonparoxysmal AF, renal dysfunction, diabetes, and underlying heart disease pre-RFCA. HF hospitalizations occurred more often in patients with than without recurrences (3.27 vs 0.84%, log-rank p <0.0001). After adjusting for confounders using a Cox model, AF recurrence remained an independent predictor of HF hospitalizations (hazard ratio [HR] 2.84, 95% confidence interval [CI] 1.80 to 4.47, p <0.0001). AF recurrence was a distinct HF hospitalization risk in patients with a left ventricular ejection fraction ≥50% (HR 4.54, 95% CI 2.38 to 8.65, p <0.0001) but not <50% (HR 1.31, 95% CI 0.65 to 2.62, p = 0.45), with significant interactions. Furthermore, patients with AF recurrences within 1 year had a greater HF hospitalization risk after 1 year (1.61% vs 0.79%, log-rank p = 0.019). In conclusion, AF recurrence after RFCA was independently associated with HF hospitalizations.

Extensive ablation strategy for persistent atrial fibrillation impairs left atrial function but reduces recurrence rate

Background

In catheter ablation for persistent atrial fibrillation (AF), extensive ablation strategy, such as linear ablation and/or complex fractionated atrial electrogram (CFAE) ablation in addition to pulmonary vein isolation (PVI-plus), might impair left atrial function more severely than PVI-alone strategy.

Purpose

The aim of this study is to investigate the impact of extensive ablation strategy on LA function and assess the relationship between post-ablation LA function and recurrence.

Methods

This study is a post-hoc subanalysis of the EARNEST-PVI randomized controlled trial, which investigated the efficacy of the PVI-alone strategy in comparison with PVI-plus strategy for persistent AF. From the 497 participants of EARNEST-PVI trial, we enrolled 191 patients with full datasets of pre- and post-ablation cardiac computed tomography (CT) at our Hospital. Patients were divided into PVI-alone and PVI-plus groups. Within one month before and 3 months after ablation, LA volume index (LAVI) and LA emptying fraction (LAEF) were calculated by using the Comprehensive Cardiac Analysis software on the Extended Brilliance Workspace. We assessed i) post-ablation LA function, ii) AF/atrial tachycardia (AT) -free rate after single and final session, and iii) relationship between post-ablation LAEF and ablation success in each group.

Results

The indices of baseline LA remodeling were not different between PVI-alone (N=96) and PVI-plus groups (N=95) [LAVI: 71.4 (57.8, 82.0) vs. 68.7 (61.0, 78.1), P=0.92, LAEF: 13.7 (10.0, 17.4) vs. 13.0 (10.0, 16.9), PVI-alone vs. PVI-plus, P=0.78]. In overall patients, post-ablation LAEF did not differ among them [34.4 (26.1, 40.7) vs. 31.6 (26.0, 37.4), P=0.13]. In the analysis of patients showing sinus rhythm during the CT study, LAEF was significantly higher in PVI-alone (N=87) than in PVI-plus group (N=93) [35.7 (29.0, 41.0) vs. 31.7 (26.1, 37.5), P=0.011] (Figure 1A). AF/AT-free survival rate during median follow-up of 44 months was not different after first session (63.5% vs. 68.4%, P=0.33), while PVI-plus had a tendency towards higher success rate after final session (72.9% vs. 84.2%, P=0.053) (Figure 2). In receiver operating characteristics analysis for recurrence after first session, post-ablation decreased LAEF had significantly related to recurrence after PVI-alone (AUC: 0.733, P&lt;0.0001), but not after PVI-plus (AUC: 0.567, P=0.31) (Figure 1B, C).

Conclusion

Compared with PVI-alone strategy, PVI-plus strategy damaged LA function more severely, but tended to be related to higher success rate. Post-ablation LA function was related to recurrence in PVI-alone, but not in PVI-plus. Extensive ablation might have additional anti-arrhythmic effect regardless of iatrogenic myocardial damage. Myocardial injury by extensive ablation may less attribute to recurrence than intrinsic damage of LA.

Funding Acknowledgement

Type of funding sources: None.

Development of the new risk score to predict occurrence of atrial fibrillation early after acute myocardial infarction

Background/Introduction

New onset of atrial fibrillation (AF) is associated with adverse short- and long-term outcomes after acute myocardial infarction (AMI), and its prediction is relevant for the risk stratification in patients with AMI. Although several risk scores were developed for AF in the general population, there is no established risk score for AF occurrence after AMI.

Purpose

To develop a risk score to predict occurrence of AF early after AMI.

Methods

We enrolled consecutive 751 patients with AMI who admitted to our hospital between April 2006 and September 2012 for the present study. New occurrence of AF was defined as AF detected during hospital stay in a patient showing normal regular sinus rhythm at admission. Parameters relevant to the occurrence of AF was selected from the clinical characteristics, physical status and blood test data at admission, and peak CK/CK-MB, by stepwise logistic regression analysis. We constructed a risk score model to predict the new occurrence of AF, using selected parameters and their logistic regression coefficients. C-statistics was determined by constructing a receiver operating characteristic curve to evaluate the accuracy of the risk score for prediction of AF occurrence.

Results

We excluded 48 patients (6.4%) who had AF at admission, and 208 patients without sufficient data at admission, and thus, the study group consisted of 459 patients (age; 65±13 years, male gender; 79.6%). New AF occurrence was observed in 72 patients (14.5%). The following 7 parameters was selected as parameters related with AF (as p&lt;0.1); Inferior/posterior AMI, use of β blockers, use of diuretics, single vessel disease, absence of reperfusion therapy, systolic blood pressure (sBP) at admission, and smoking. One point was given to sBP&gt;128mmHg, 2 points to absence of reperfusion, and one point to other parameters. Sum of these points was calculated as the AF risk score (Table 1). AF occurred in 27.1% of patients with ≥5 points whereas it was observed 5.2% of those with &lt;5 points. C-statistics of the risk score was 0.75 (95% CI 0.68–0.83).

Conclusion

We developed a novel risk score to estimate the risk of AF occurrence early after AMI, which can be a useful tool for the risk stratification after AMI.

Funding Acknowledgement

Type of funding sources: None.

Untreated sleep apnea and left atrial dilatation in patients with atrial fibrillation prior to catheter ablation

Background

Sleep apnea and left atrial dilatation are both risk factors for an arrhythmia recurrence after catheter ablation (CA) of atrial fibrillation (AF). Negative intrathoracic pressure fluctuations during an obstructive apnea episode may cause the left atrium to distend and stretch its wall. Whether sleep apnea is associated with left atrial dilatation in patients receiving CA of AF remains unknown.

Purpose

We sought to elucidate whether moderate or severe untreated sleep apnea was associated with left atrial dilatation in patients with AF before CA.

Methods

This study was conducted under a retrospective, single-center, observational design. The data were derived from screening tests for sleep apnea, which were routinely performed in patients scheduled to receive CA of AF in our institution. After excluding patients who were already diagnosed with sleep apnea, we enrolled 1265 consecutive patients (age 65±11 years, 27.8% females, and 46.2% of non-paroxysmal AF) who underwent both home sleep apnea testing and multidetector computed tomography (MDCT) before the CA of AF. The severity of the sleep apnea was evaluated by the apnea-hypopnea index (AHI) using a watch-type peripheral arterial tonometry. Left atrial dilatation was evaluated by the left atrial maximum volume (LA max V) using 256-slice MDCT.

Results

The age was 65±11 years, 27.8% were females, and 46.2% had non-paroxysmal AF. The mean AHI was 20.3±15.3 and LA max V 105±34 ml (R2=0.075, p&lt;0.0001). LA dilatation was defined by larger than mean LA max V (LA max V≥105 ml). We examined an LA max V≥105 ml as a predictor. After an adjustment by an advanced age (≥65 years), non-paroxysmal AF, male sex, obesity, hypertension, and congestive heart failure, all of which were significant predictors of an LA max V≥105ml in the univariate analysis, moderate or severe sleep apnea (AHI≥15) was a significant predictor of an LA max V≥105 ml (odds ratio 1.63, 95% confidence interval 1.24–2.14, p=0.0005).

Conclusion

Among the patients scheduled to receive catheter ablation of AF, moderate or severe sleep apnea was independently associated with left atrial dilatation.

Funding Acknowledgement

Type of funding sources: None.

Sex differences in terms of recurrent atrial fibrillation after catheter ablation according to the history of heart failure: insights from the Kansai Plus Atrial Fibrillation (KPAF) registry

Background

There are significant differences in the prevalence and prognosis of cardiovascular diseases between male and female. We previously reported that catheter ablation (CA) of atrial fibrillation (AF) was less effective in female than male, but whether their history of heart failure influence the recurrence after CA of AF remains still unknown.

Purpose

We sought to clarify sex differences in terms of AF recurrence after RFCA of AF according to the history of heart failure.

Methods

We conducted a large-scale, prospective, multicenter, observational study (Kansai Plus Atrial Fibrillation Registry). We enrolled 5010 consecutive patients who underwent an initial RFCA of AF at 26 centers (64±10 years; 1369 [27.3%] females; non-paroxysmal AF, 35.7%). The median follow-up duration was 2.9 years.

Results

Fourteen % of female had a history of heart failure prior to CA, while 12.8% of male had a history of heart failure at baseline (p=0.29). The 3-year cumulative incidence of AF recurrence after a single procedure was 43.3% in female and 39.0% in male (log rank P=0.0046). In patients with the history of heart failure, AF recurrence rates were 42.2% in female and 45.8% in male (log rank P=0.51). On the other hand, in patients without history of heart failure, more females experienced AF recurrence (female vs. male, 43.5% vs. 38.0%, log rank P=0.001).

The rate of AF recurrence after multiple procedures was higher in female (24.2% vs. 19.6%, log rank P&lt;0.0001). AF recurrence rates were similar between sexes in patients with history of heart failure (female vs. male, 26.0% vs. 26.7%, log rank P=0.86), while AF recurrence rates were higher in female without history of heart failure than those in male (females vs. males, 23.9% vs. 18.5%, log rank P&lt;0.0001).

Conclusion

The Kansai Plus Atrial Fibrillation Registry revealed a distinct sex difference in terms of the AF recurrence after CA of AF. Females had higher recurrence rates compared with males in patients without history of heart failure, while recurrence rates were similar between sexes in patients with history of heart failure.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Research Institute for Production Development in Kyoto, Japan.

POS0390 GENES OF “DEFENSE RESPONSE TO VIRUS” IN PERIPHERAL BLOOD OF ANTI-MDA5 POSITIVE DERMATOMYOSITIS WERE UPREGULATED AS COMPARE WITH OTHER FORMS OF DERMATOMYOSITIS. ~SUPPRESSING RIG-I LIKE RECEPTOR SIGNALING OR TYPE 1/2 INTERFERON SIGNALING WERE THE KEYS FOR SURVIVAL

Background

Anti-melanoma differentiation-associated gene 5–positive dermatomyositis (MDA5 DM) is a rare but distinct subtype of idiopathic inflammatory myopathy (IIM) that is characterized by high mortality due to rapid progressive interstitial lung disease (ILD). MDA5 is a cytosolic protein and a family of retinoic-acid inducible gene-I (RIG-I) like receptor, which functions as a virus RNA sensor and induces the production of type I interferons (IFN-I) and proinflammatory cytokines. This leads to the death of infected cells and the activation of the antigen-specific antiviral immune response. Although the pathogenesis of MDA5 DM is largely unknown, a hypothesis that pathogenic involvement of anti-MDA5 antibodies has been proposed. Recently, similarities have been noted between multifaceted features of COVID-19 and MDA5 DM, which suggests shared underlying autoinflammatory mechanisms.

Objectives

To detect the critical actors in the pathogenesis of MDA5 DM by gene expression analysis of peripheral blood.

Methods

Total of 31 DM cases were investigated, including anti-aminoacyl-tRNA synthetase positive (ARS) DM (n=12), MDA5 DM (n=7, survivor=3) and others (n=12). Peripheral blood was drawn at baseline and 2 to 3 months after treatments. Total RNAs were then extracted with using PAXgene miRNA kit. After quantifying the expressions of transcripts by multiplex sequencing. And then, hierarchical clustering analysis, enrichment analysis using gene ontology (GO) terms, single sample gene set enrichment analysis (ssGSEA) and weighted gene co-expression network analysis (WGCNA) were performed.

Results

The hierarchical clustering with expression profiles of peripheral blood at baseline showed major 3 clusters. Interestingly, ARS DM cases were segregated into right side of the 3rd cluster while MDA5 DM cases fell into 1st and 2nd clusters. ARS and MDA5 DM were clearly discriminated if differentially expressed genes (DEGs) between these subtypes of DM were analyzed. By GO enrichment analysis, the terms, such as related to “defense response to virus” including “type1 interferon signaling pathway” were found in the DEGs. In the MDA5 DM cases, ssGSEA revealed that genes of “Fcγ receptor mediated phagocytosis pathway” or “complement and coagulation cascade” were significantly enriched and WGCNA showed that pathways of “T-cell antigen receptor signaling” or “lung fibrosis” were significantly upregulated. Next, we also investigated the DEGs of peripheral blood at 2-3 months after treatment between survival and fatal cases in MDA5 DM. We found that suppressing RIG-I like receptor and type 1 and type 2 interferon (IFN) signaling were the keys for survival.

Conclusion

MDA5 is a key sensor of several RNA viruses including coronavirus families and then activate antiviral gene transcription such as type 1 IFN genes, leading to establish an antiviral host response. As the pulmonary damage of COVID-19 is known to be difficult to distinguish from the ILD associated with anti-MDA5 DM, the life-threating ILD of MDA5 DM may be caused by the over-activation of RIG-I like receptor signaling via MDA5. The hypothesis is supported by our findings that the defining features of MDA5 DM are activation of “type 1 IFN pathways” and antigen-specific antiviral immune responses including “Fcγ receptor mediated phagocytosis pathway” or “T-cell antigen receptor signaling”. As the levels of anti-MDA5 antibodies reported to be important prognostic parameter, it may be involved in pathogenesis of MDA5 DM. As we found that suppression of type 1 and type 2 IFN signaling were the keys for survival, it seems to be reasonable to use inhibitors of Janus Kinases (JAK) for treatment of MDA5 DM.

Disclosure of Interests

Yoshinobu Koyama Speakers bureau: Abbvie, Asahikasei, Ayumi, BMS, Eli-Lilly, Mitsubishi Tanabe, Grant/research support from: Abbvie, GSK, Yoshiharu Sato: None declared, Moe Sakamoto: None declared

Absence of first-pass isolation is associated with poor pulmonary vein isolation durability and atrial fibrillation ablation outcomes

BACKGROUND

Pulmonary vein (PV) reconnection is the main cause of atrial fibrillation (AF) recurrence. This study aimed to examine the effect of first-pass PV isolation (PVI) on PV reconnection frequency during the procedure and on AF ablation outcomes.

METHODS

This retrospective study included 446 patients with drug-refractory AF (370 men, aged 64 ± 10 years) who underwent initial PVI using an open-irrigated contact force catheter between January 2015 and October 2016. We investigated the effect of first-pass PVI on PV reconnection during spontaneous PV reconnection and dormant conduction after an adenosine triphosphate challenge.

RESULTS

First-pass PVI was achieved in 69% (617/892) of ipsilateral PVs, of which we observed PV reconnection during the procedure in 134 (22%) PVs. This value was significantly lower than that observed in those without first-pass PVI (50%, 138/275) (P < .0001). We divided the subjects into two groups based on the presence or absence of first-pass PVI in at least one of two ipsilateral PVs: first-pass (n = 383, 86%) and non-first-pass groups (n = 63, 14%). The 2-year AF recurrence-free rate was significantly higher in the first-pass group than in the other group (75% vs 59%, log-rank P = .032). In 78 patients with repeat AF ablation, the PV reconnection rate in the second procedure was significantly lower in PVs that had first-pass isolation in the first procedure (34% vs 73%, P < .0001).

CONCLUSIONS

Absence of first-pass PVI was associated with a higher frequency of spontaneous PV reconnection and dormant conduction and poor ablation outcomes. First-pass isolation may be a useful marker for better PVI durability.

The number of circulating CD34-positive cells is an independent predictor of coronary artery calcification progression: Sub-analysis of a prospective multicenter study

Background

Decreases in circulating CD34-positive cells are associated with increases in cardiovascular events. We investigated the association between the number of CD34-positive cells and the progression of coronary artery calcification (CAC), a marker of atherosclerosis, in patients with hypercholesteremia under statin therapy in a sub-analysis of a multicenter study.

Methods

In the principal study, patients with CAC scores of 1–999 were treated with pitavastatin. Measurement of CAC by non-enhanced computed tomography and a blood test were performed at baseline and at 1-year follow-up. Patients were divided into two groups: CAC progression (change in CAC score > 0) and non-progression. The number of circulating CD34-positive cells was counted using flow cytometry.

Results

A total of 156 patients (mean age 67 years, 55% men) were included in this sub-analysis. CD34 positive cell numbers at baseline as a continuous variable was inversely correlated with annual change in the log-transformed CAC score (r = –0.19, p = 0.02). When patients were divided into high and low CD34 groups based on the median value of 0.8 cells/μL, the adjusted change in CAC score in the low-CD34 group was significantly greater than that in the high-CD34 group (54.2% vs. 20.8%, respectively, p = 0.04). In multiple logistic analysis, a low CD34-positive cell number was an independent predictor of CAC progression, with an odds ratio of 2.88 (95% confidence interval 1.28–6.49, p = 0.01).

Conclusions

Low numbers of CD34-positive cells are associated with CAC progression in patients with hypercholesterolemia under statin therapy. The number of CD34-positive cells may help to identify patients at increased cardiovascular risk.

Association between myocardial wall thickness and left ventricular functional recovery after catheter ablation of atrial fibrillation in patients with reduced ejection fraction

Background

Catheter ablation of atrial fibrillation (AFCA) is an effective treatment to develop left ventricular (LV) functional recovery. However, the degree of recovery differs between individuals due to the different extent of myocardial fibrosis and scarring.

Purpose

To examine whether pre-ablation LV wall thickness (WT) and its regional heterogeneity predict LV functional recovery after AFCA in patients with LV systolic dysfunction.

Methods

Of 3682 consecutive patients who underwent first-time AFCA between January 2012 and September 2020 in our institution, 174 (age, 63±10 years; male, 83%; ischemic cardiomyopathy, 14%) with a baseline LV ejection fraction (LVEF) of &lt;40% were retrospectively evaluated. They were subjected to 256-slice MDCT scanning at baseline and 3 months after AFCA. Baseline WT was evaluated by 16-segment model. Mean and standard deviation (SD) of 16 regional WT were calculated in both end-systolic and end-diastolic phase.

Results

LVEF significantly improved from 30±7% to 57±17% (p&lt;0.001) after AFCA. Increase in LVEF (delta-LVEF) was positively correlated with baseline end-diastolic WT (r=0.31, p&lt;0.001) and negatively correlated with SD of end-systolic WT (r=−0.21, p=0.007). Independent of WT measurements, delta-LVEF was negatively correlated with LV end-diastolic volume (r=−0.42, p&lt;0.001). We created a scoring system to predict the degree of wall motion recovery using the median value of the 3 variables; assigned 1 point each for end-diastolic WT &gt;7.4mm, SD of end-systolic WT &lt;1.61mm, and LV end-diastolic volume &lt;125ml. The model successfully predicted improvement in LVEF after AFCA (0 point (N=13) vs. 1 point (N=72) vs. 2–3 point (N=89), 11±16% vs. 20±17% vs. 33±12%, p&lt;0.001).

Conclusion

Myocardial WT and its regional heterogeneity as well as LV end-diastolic volume predicted functional recovery after AFCA in patients with reduced LVEF.

Funding Acknowledgement

Type of funding sources: None.

Prediction of functional capacity by the HFA-PEFF score in patients with acute decompensated heart failure with preserved ejection fraction: a post-hoc analysis from the PURSUIT-HFpEF registry

Background

Diagnosing heart failure with preserved ejection fraction (HFpEF) is still challenging, and the H2FPEF- and the HFA-PEFF score were proposed as simple and reliable diagnostic tools. We recently reported that the HFA-PEFF score was significantly associated with the composite endpoint of all-cause death and heart failure readmission in patients with acute decompensated HFpEF (Sotomi. Eur J Heart Fail, in press).

Purpose

To investigate the relation whether the HFA-PEFF or H2FPEF score can evaluate functional capacity in patients with HFpEF

Methods

We calculated H2FPEF score and the second step of HFA-PEFF score among the registered patients in the PURSUIT-HFpEF (Prospective, Multicenter, Observational Study of Patients with Heart Failure with Preserved Ejection Fraction) study, which is a multicenter registration of patients hospitalized for acute decompensated HFpEF. We performed 6 minute walk (6MW) test and measured NT-proBNP before discharge. We followed the study patients for median of 360 days (IQR 237–630 days) to observe the major adverse cardiovascular events (MACE; composite of death, heart failure hospitalization and stroke).

Results

We enrolled 757 patients (age 81±9 years, male gender 45%) hospitalized for acute decompensated HFpEF for the present study. The H2FPEF score was obtained in 588 (77.7%) patients and all patients had ≥2 points. The HFA-PEFF score was obtained in 615 (81.2%) patients, though global longitudinal strain was not available. We divided these patients into 3 groups based on the HFA-PEFF score (score 2 to 4, 5, and 6) or on the H2FPEF score (score 0 to 3, 4 to 5 and 6 to 8). There were a significant difference in NT-pro BNP between 3 groups based on HFA-PEFF score (p=0.01, Table 1), and patients with score 6 had significantly higher NT-proBNP than those with score 2 to 4 (p=0.02). A significant difference was observed in 6MW distance among these groups (p=0.04, Table), and those with score 6 had significantly shorter distance than those with score 2 to 4 (p=0.04). Cox proportional hazard model selected HFA-PEFF score as a significant predictor for MACE, and Kaplan-Meier survival analysis demonstrated that classification of HFA-PEFF score significantly stratified the patients' risk for MACE. On the other hand, there was no significant difference in 6MW distance among 3 groups based on H2FPEF score (p=0.53), and H2FPEF score was not an independent predictor for MCE by the Cox model analysis. Moreover, the lowest H2PEF score group had higher NT-proBNP than other 2 groups (p=0.02)

Conclusions

The HFA-PEFF score predicted functional capacity as well as prognosis in patients hospitalized for HFpEF, while the H2PEF score did not.

Funding Acknowledgement

Type of funding sources: None. Table 1

Tissue Mitral Annular Displacement in Patients With Myocardial Infarction - Comparison With Global Longitudinal Strain

Background: Global longitudinal strain (GLS) can predict prognosis after myocardial infarction (MI). Tissue mitral annular displacement (TMAD) is another index of longitudinal left ventricular deformity, and is less dependent on image quality than GLS. We investigated the relationship between TMAD and GLS, and their ability to predict outcomes after MI. Methods and Results: GLS and TMAD were measured on echocardiograms 2 weeks after MI in 246 consecutive patients (median age 62 years, 85.7% male). TMAD was measured from apical 4- and 2-chamber views (TMAD_4ch and TMAD_2ch, respectively), and a mean value (TMAD_av) was calculated. TMAD_4ch, TMAD_2ch, and GLS were successfully measured in 240 (97.5%), 210 (85.3%) and 214 patients (87.0%), respectively. All TMAD parameters were significantly correlated with GLS (R=0.71-0.75) and left ventricular ejection fraction (LVEF; R=0.48-0.53). TMAD parameters were weakly correlated with peak creatine kinase (CK; R=0.20) and CK-MB (R=0.21-0.25). GLS and TMAD_av were significantly associated with LVEF after 6 months (R=0.48-0.53) and all-cause mortality during the follow-up period (median 1,242 days). TMAD_av discriminated patients with higher all-cause mortality when patients were divided into 3 groups, namely upper 25%, middle range, and lower 25% of TMAD_av (P=0.041, log-rank test). GLS detected high-risk patients using 15.0% as a cut-off value. Conclusions: TMAD could be a simple and reliable alternative to GLS for predicting outcomes in patients with MI.

Decrease in red cell distribution width as a useful predictor of success after catheter ablation for atrial fibrillation: a retrospective multi-center study

Red cell distribution width (RDW) is reportedly associated with cardiovascular events, including atrial fibrillation (AF). We investigated whether the RDW values were associated with the outcomes of catheter ablation for AF. This retrospective multicenter study included 501 patients with AF (239 paroxysmal AF cases, 196 persistent AF cases, and 66 long-standing persistent AF cases) who underwent initial AF ablation between March 2017 and May 2018. The RDW values were evaluated before and at 1-3 months after the procedure. The patients were stratified based on the recurrence of AF within 1 year after the index procedure with a blanking period of 3 months into recurrence group (107 patients, 21.4%) and no-recurrence group (394 patients, 78.6%). There were no significant differences in preoperative RDW values between the groups (p = 0.37). The RDW value did not change significantly after the ablation in the recurrence group (13.55-13.60%, p = 0.37), although it decreased significantly in the no-recurrence group (13.64-13.37%, p < 0.001). Multivariate Cox proportional hazards regression analyses revealed that a postoperative change in RDW (ΔRDW) was independently associated with AF recurrence (hazard ratio 2.00, 95% confidence interval 1.42-2.76, p < 0.001). Receiver operating characteristic curve analysis revealed that a ΔRDW cut-off value of - 0.1% provided a c-statistic of 0.65 for predicting AF recurrence. Decrease in RDW during the blanking period after ablation independently predicted the 1-year success of AF ablation.

Post-ablation left atrial function impacts long-term recurrence of atrial fibrillation after ablation

Left atrial (LA) function can help predict various cardiovascular events. Catheter ablation for atrial fibrillation (AF) modifies baseline LA function through the maintenance of sinus rhythm and myocardial injury. We investigated the impact of post-ablation LA function on recurrence of AF after ablation and identified the predictors of reduced post-ablation LA function. A total of 616 patients who underwent AF ablation (paroxysmal, N = 310; non-paroxysmal, N = 306) were retrospectively examined with cardiac computed tomography at baseline and 3 months after the final ablation procedure. Post-ablation LA emptying fraction (LAEF_post) was calculated. We evaluated the association between LAEF_post and recurrence of AF after the final ablation procedure. Further, we assessed the predictors of reduced LAEF_post. The recurrence rate of AF was 72.7% after the final ablation procedure [median follow-up 48 months (48.0, 48.0), total number of ablation sessions: 1.4 ± 0.7]. Multivariate analysis revealed that LAEF_post was associated with the recurrence of AF (hazard ratio/10% increase: 0.62, 95% confidence interval: 0.51-0.75, P < 0.0001). LAEF_post had a mild predictive power for recurrence of AF (c-statistics: 0.670, optimal cutoff: 26.36%, P < 0.0001). The recurrence-free proportion among patients with reduced LAEF_post (< 26.36%, N = 100) and those with preserved LAEF_post (≥ 26.36%, N = 516) was 40% and 79%, respectively (P < 0.0001). The predictors of reduced LAEF_post were low pre-ablation LAEF, high pre-ablation LA volume, low body mass index (BMI), and female sex. Further, reduced LAEF_post was associated with the total number of ablation sessions and extra-pulmonary vein LA ablation. In conclusion, reduced LAEF_post was associated with recurrence of AF after ablation. Advanced LA remodeling, low BMI, and female sex could predict reduced LAEF_post. Although additional ablation was associated with reduced LAEF_post, it remains unclear whether reduced LAEF_post resulted from the additional ablation. Reduced LAEF_post might help stratify patients with ablation-refractory AF.

Sex differences in atrial fibrillation ablation outcomes: insights from a large-scale multicentre registry

AIM

The impact of sex differences on the clinical outcomes of radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) is controversial. We investigated the sex differences regarding the efficacy and clinical outcomes of RFCA of AF.

METHODS AND RESULTS

We conducted a large-scale, prospective, multicentre, observational study (Kansai Plus Atrial Fibrillation Registry). We enrolled 5010 consecutive patients who underwent an initial RFCA of AF at 26 centres (64 ± 10 years; non-paroxysmal AF, 35.7%). The median follow-up duration was 2.9 years. Female patients (n = 1369, 27.3%) were older (female vs. male, 68 ± 9 vs. 63 ± 11 years, P < 0.0001) with a lower prevalence of non-paroxysmal AF (27.1% vs. 38.9%, P < 0.0001). Fewer females experienced time-dependent pulmonary vein (PV) reconnections and more females received a non-PV foci ablation than males in the index RFCA. The 3-year cumulative incidence of AF recurrences in the multivariate analysis after single procedures was significantly higher in females than males (43.3% vs. 39.0%, log rank P = 0.0046). Females remained an independent predictor of AF recurrence (hazard ratio 1.24; 95% confidence interval 1.12-1.38, P < 0.0001). The AF recurrence rates after multiple procedures were also higher in females, but fewer females experienced PV reconnections during second sessions. More females experienced de novo pacemaker implantations during the long-term follow-up. Females were associated with a higher risk of heart failure hospitalizations and major bleeding after RFCA in the multivariate analysis.

CONCLUSIONS

Females experienced more frequent AF recurrences probably due to non-PV arrhythmogenicity and de novo pacemaker implantations than males during the long-term follow-up after RFCA of AF.

Development of an application tool to support returnees in Fukushima

To promote radiation protection and health promotion among returning residents (returnees) in coastal areas of Fukushima, eHealth principles were used to develop a new application tool (app) that can record radiation exposure and health status while providing comprehensive support to returnees. Intended users are returnees and health and welfare workers. After assessing their needs, a flowchart and prototype for operational logic were created using commercially available software tools. Professional developers will focus on improving the user interface and ensuring data security. The finished app will be compatible with mobile telephones and tablets. Utility and ease of use are paramount to serve returnees of all ages effectively.

POS0881 DETECTION OF THE GENE EXPRESSIONS IN PERIPHERAL BLOOD INVOLVED IN THE PROGRESSION OF PULMONARY VESSEL DISEASE AT THE SUBCLINICAL STAGE OF PULMONARY HYPERTENSION ASSOCIATED WITH SYSTEMIC SCLEROSIS

Background:

Pulmonary hypertension (PH) is prominent as a vascular involvement of systemic sclerosis (SSc), which remains a leading cause of death in spite of current best treatments. Recently, hemodynamic definition of PH was updated from mPAP≥25mmHg to mPAP>20mmHg and PVR≥3WU. Although new definition may improve the prognosis of PH associated with SSc by giving a chance to start management early, it may be insufficient as more than 2/3 of the pulmonary circulation is already impaired by the time of meeting the definition. Therefore, the ideal therapeutic intervention should be started at the subclinical stage of PH in SSc patients, but little is known about underlying pathological mechanisms at the stage. In this study, we investigate progression to exercise-induced PH (exPH)1), which is considered subclinical PH, in the prospective registry of high-risk population for developing PH associated with SSc.

Objectives:

To detect the gene expressions in peripheral blood involved in the progression of pulmonary vessel disease (PVD) at the subclinical stage of PH associated with SSc.

Methods:

Total of 180 patients who had not met PH criteria with Raynaud phenomenon, skin sclerosis or SSc-related autoantibody was registered. To detect the early PVD, exercise Doppler echocardiography (exDE) was carried out every 6 or 12 months for up to 6 years. The definition of exPH was maximum sPAP>40mmHg or increase in sPAP>20mmHg estimated by exDE during exercise. For gene expression analysis, total RNAs from whole peripheral blood cells were extracted by PAXgene system, and then multiplex sequencing was done. To identify candidate genes involved in the progression to exPH, random forest machine learning method was employed. Volcano plots, a scatter plots to visualize fold-changes and p-values of differentially expressed genes (DEGs) between exPH and others (exN), were also used for seeking the important genes for disease progression.

Results:

At the time of registration, 34.4% of patients met exPH criteria, and 15.6% of patients developed exPH during follow-up period (35.0±18.1 months). Expression of TNF gene was selected as the most useful genes to predict progression to exPH by random forest, and the accuracy of the model was about 87%. Volcano plots indicated that expressions of TMEM176A and TMEM176B were prominent (fold-change >2.4 and -log10 p-value >3.5) in exPH patients. The accuracy was improved to 90% if the expression of TNF and TMEMA/B were used for the prediction of progression to exPH. We found that statistically significant increase in the expression of TNF was eliminated at the time of fulfilling the exPH criteria, while increase in expressions of TMEM A/B were still kept.

Conclusion:

It was reported that TNFα drives pulmonary arterial hypertension by suppressing the BMP type-II receptor and altering NOTCH signalling2). Our findings suggest that TNFα plays important role only in the period of pre-exPH. On the other hand, increase in expressions of TMEM A/B were observed through the period of pre-exPH to post-exPH. It suggests that there are multiple phases before developing PH associated with SSc. It is very important to understand the phases for the precise treatment to arrest the progression of PVD.

References:

[1]R. Naeije et al., Am J resp and critical care med 187, 576-583 (2013). 2) LA. Hurst et al., Nat Commun. 13;8:14079 (2017).

Disclosure of Interests:

Yoshinobu Koyama Speakers bureau: Asahikasei, Ayumi, BMS, Mitsubishi Tanabe, Shin-nihon, Paid instructor for: Asahikasei, Asteras, BMS, Grant/research support from: Eli-Lilly, Yoshiharu Sato: None declared, Tatsuma Shoji: None declared, Soichiro Fuke: None declared, Takatsune Umayahara: None declared, Moe Sakamoto: None declared

Towards a Clinical Implementation of Measuring the Elastic Modulus of the Aorta from Cardiac Computed Tomography Images

OBJECTIVE

The elasticity of the aortic wall varies depending on age, vessel location, and the presence of aortic diseases. Noninvasive measurement will be a powerful tool to understand the mechanical state of the aorta in a living human body. This study aimed to determine the elastic modulus of the aorta using computed tomography images.

METHODS

We constructed our original formulae based on mechanics of materials. Then, we performed computed tomography scans of a silicon rubber tube by applying four pressure conditions to the lumen. The segment elastic modulus was calculated from the scanned images using our formulae. The actual modulus was measured using a tensile loading test for comparison.

RESULTS

The segment moduli of elasticity from the images were 0.525 [0.524, 0.527], 0.524 [0.520, 0.524], 0.520 [0.515, 0.523], and 0.522 [0.516, 0.532] (unit: MPa, median [25%, 75% quantiles]) for the four pressure conditions, respectively. The corresponding measurements in the tensile test were 0.548 [0.539, 0.566], 0.535 [0.528, 0.553], 0.526 [0.513, 0.543], and 0.523 [0.508, 0.530], respectively. These results indicated errors of 4.2%, 2.1%, 1.1%, and 0.2%, respectively.

CONCLUSION

Our formulae provided good estimations of the segment elastic moduli of a silicon rubber tube under physiological pressure conditions using the computed tomography images.

SIGNIFICANCE

In addition to the elasticity, the formulae provide the strain energy as well. These properties can be better predictors of aortic diseases. The formulae consist of clinical parameters commonly used in medical settings (pressure, diameter, and wall thickness).

Usefulness of Post-Procedural Plasma Brain Natriuretic Peptide Levels to Predict Recurrence After Catheter Ablation of Atrial Fibrillation in Patients With Left Ventricular Systolic Dysfunction

Catheter ablation (CA) of atrial fibrillation (AF) improves cardiac function, resulting in a decrease in plasma brain natriuretic peptide (BNP) levels in patients with reduced left ventricular ejection fraction (LVEF). This study sought to examine the pre-procedural and post-procedural correlations between BNP levels and cardiac function and the associations between the BNP levels and recurrence after CA in patients with AF and reduced LVEF. Of 3142 consecutive patients who underwent first-time CA of AF at our institute, a total of 217 patients with LVEF <50% were enrolled. Significant decrease in BNP levels (from a median of 198 [interquartile range 113 to 355] to 47.7 [22.7 to 135] pg/ml, p <0.001) and improvement in LVEF (from 39±9% to 61±16%, p <0.001) were observed 3 months after CA. There was a linear correlation between log-transformed BNP levels and cardiac measures (LVEF: r = -0.64; LV end-diastolic volume: r = 0.25; LV end-systolic volume: r = 0.43; left atrial volume: r = 0.52; all p <0.001). During a median follow-up of 35 months, AF recurrence after a 3-month blanking period was observed in 80 patients (37%). Cox proportional hazard regression analysis after adjustment for cardiac measures significant in univariate analysis revealed that early recurrence within the blanking period (hazard ratio, 4.88; 95% confidence interval, 2.89 to 8.25) and elevated post-procedural BNP levels (2.02 per unit log increase; 1.14 to 3.56) were significant predictors of AF recurrence, but pre-procedural BNP was not. In conclusion, post-procedural BNP levels at the end of the blanking period predicted subsequent AF recurrence in patients with reduced LVEF, independent of early recurrence.

Home Sleep Apnea Test to Screen Patients With Atrial Fibrillation for Sleep Apnea Prior to Catheter Ablation

BACKGROUND

Whether all atrial fibrillation (AF) patients should be evaluated for sleep apnea before catheter ablation (CA) remains controversial. Watch-type peripheral arterial tonometry (W-PAT) is a home sleep testing device and an easier tool for diagnosing sleep apnea than polysomnography. We investigated the prevalence and predictors of sleep apnea using W-PAT in unscreened sleep apnea patients with AF before CA.Methods and Results:The study was conducted under a retrospective, single-center, observational design. We included 776 consecutive patients who underwent both W-PAT and AF ablation. Sleep apnea assessments were successfully performed in 774 patients (99.7%; age 65±11 years, 73.3% male; body mass index [BMI] 24.1±3.5, 56.8% paroxysmal AF). The mean apnea-hypopnea index (AHI) was 20.1±15.6. Although 81.7% of the patients had normal Epworth sleepiness scores (mean 6.5), only 88 (11.4%) had a normal AHI (AHI <5) and 412 (53.2%) had moderate-severe sleep apnea (AHI ≥15). Obesity, male sex, nonparoxysmal AF, hypertension, and a left atrial diameter (LAd) ≥40 mm were predictors of moderate-severe sleep apnea. However, the prevalence of moderate-severe sleep apnea in patients without those predictors (i.e., non-obesity (44.2%), female sex (43.0%), paroxysmal AF (43.9%), no hypertension (45.5%)), and LAd <40 mm (41.0%) was considerably high.

CONCLUSIONS

Almost all patients successfully underwent W-PAT to diagnose sleep apnea. Patients undergoing AF ablation had a high prevalence of sleep apnea, and screening for sleep apnea was important in those patients even if they did not have sleepiness or risk factors.

The utility of a novel approach to quantify dyssynchrony by multidetector computed tomography

Funding Acknowledgements

Type of funding sources: None.

Background

Quantification of left ventricular (LV) dyssynchrony is of great interest for resynchronization therapy (CRT). Recently, cardiac computed tomography (CCT) is feasible for evaluation of dyssynchrony. Our aim was to assess a novel simplified approach using CCT to quantify LV dyssynchrony.

Methods

We studied 346 consecutive patients with a wide range of QRS width and ejection fractions (EF). Electrocardiogram-gated contrast-enhanced 256-slice multidetector CT (Brilliance 256 iCT, Philips Medical Systems) was performed before CRT. After CCT scan, the LV endocardial boundaries from short-axis images reconstructed at 5% increments of cardiac cycle were automatically detected, and a time from R-wave to maximal wall motion was calculated for each of the 16 standardized segments for all slices using software "Myocardial Contraction Map" (Argus, Inc Ehime, Japan). The standard deviation of all segments modified by mean heart rate (%SD) was respectively calculated as the global parameter of dyssynchrony. LVEF was also measured using MDCT.

Results

%SD was feasible in all patients, respectably. %SD was significantly different between the different QRS duration groups; narrow QRS (&lt;120ms): 9 ± 5%, relatively wide QRS (120-150 ms): 11 ± 6%, and significantly wide QRS (&gt;150 ms): 14 ± 7% (p &lt;0.001). Moreover, there was significantly difference in %SD between the different morphology groups; normal: 9 ± 7%, Non-left bundle branch block (Non-LBBB): 10 ± 6%, LBBB: 17 ± 7% (p &lt;0.001).

Conclusion

This novel simplified approach by CCT can quantify dyssynchrony in different QRS duration and morphology groups. This method has promise for clinical applications to the evaluation of patients for CRT.

Abstract Figure.

Automated heart segmentation using a convolutional neural network accelerates 3D model creation for cardiac surgery

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Japan Organization of Occupational Health and Safety

onbehalf

J3D

Introduction

Improvements in cardiovascular imaging have contributed to the accurate diagnosis and treatment of cardiovascular diseases. In recent years, we can find a new demand from surgical departments, i.e., 3D heart models of patients for preoperative simulations. However, a 3D surgical model needs a detailed segmentation of heart structures from clinical images because these details are essential for achieving accurate polygon data of an exact 3D model. Thus, in most cases, manual segmentation is required for complicated heart shapes such as the chamber wall, valves, and papillary muscles, which causes a prolonged duration time.

Purpose

We aim to achieve an automated heart segmentation using a convolutional neural network (CNN) trained using deep learning techniques for the rapid creation of 3D surgical heart models of individual patients.

Methods

We constructed our original CNN program based on the latest artificial intelligence techniques and trained it to extract shapes of the heart from cardiac computed tomography (CT) images. The training data was 361 slices selected from CT scans of 10 patients. We used data augmentation to increase the amount and diversity of the data into 24,052 slices. The training result with the best Intersection over Union (IoU), one of the evaluation metrics used in deep learning, was saved. Finally, we used the best-trained CNN to construct 3D polygon data of two surgical cases of hypertrophic obstructive cardiomyopathy (HOCM) for preoperative assessments.

Results

The IoU attained 0.85 after deep learning. The time required to complete the 3D polygon data for the first HOCM case was 5 minutes for segmentation by the trained CNN and 3 hours for data correction by a human operator. Similarly, the time required for the second case was 5 minutes for segmentation without manual correction. We had to correct the segmentation for the first case because we needed an exact 3D model for the preoperative assessment (Fig. 1). According to our records of the other eight 3D heart models in the lab, the work for a 3D polygon shape from CT images needs a median 30 hours (quartiles 23-50 hours) when the procedure is fully manual and non-continuous with breaks in between.

Conclusion

The CNN-based segmentation aided the constructing heart shapes from cardiac CT images of preoperative patients. Although the performance, reaching IoU of 0.85, was insufficient for fully automatic segmentation, the methodology can shorten the process duration from several hours to several minutes for detailed segmentation of heart structures.

We previously applied the CNN-based segmentation to the aorta, aortic stenosis valves, and atheromatous plaque in clinical images, demonstrating adequate segmentation performance. The proposed methodology can be applied as a fundamental technology of cardiovascular imaging for obtaining the actual structures of a target object as 3D coordinate values or a 3D model within a reasonable duration time.

Abstract Figure 1

Clinical significance of left ventricular reverse remodeling after catheter ablation of atrial fibrillation in patients with left ventricular systolic dysfunction

BACKGROUND

Left ventricular (LV) reverse remodeling (LVRR) after catheter ablation of atrial fibrillation (AFCA) has not been fully described. This study investigated the predictors and clinical outcomes of LVRR after AFCA in patients with LV systolic dysfunction.

METHODS

Of 3319 consecutive patients who underwent first-time AFCA between January 2012 and October 2019, 376 with a baseline LV ejection fraction of <50% were retrospectively evaluated. They were subjected to 256-slice multidetector computed tomography (MDCT) scanning at baseline and 3 months after AFCA. The LVRR was defined as a decrease in the LV end-systolic volume of ≥15%.

RESULTS

The prevalence of LVRR was 83% (n = 306). Multivariate logistic regression analysis including age, body mass index, diabetic status, beta-blocker use, and LV diastolic diameter revealed that the predictors of LVRR were non-paroxysmal atrial fibrillation (AF) (odds ratio, 2.68; 95% confidence interval, 1.42-5.05; p = 0.002) and absence of apparent underlying structural heart disease (4.81; 2.31-10.0; p <0.001). The prevalence of LVRR differed depending on AF recurrence pattern prior to the post-MDCT [no episode vs. paroxysmal episode (lasting <7 days) vs. persistent episode (lasting ≥7 days), 84% vs. 81% vs. 63%, respectively, p = 0.023]. During a median follow-up of 32 months, the incidence of paroxysmal form of AF recurrence was similar, whereas persistent form of AF recurrence was less frequent in patients with LVRR (10.5% vs. 18.6%, p = 0.018). Heart failure hospitalizations (2.3% vs. 15.7%, p <0.001), cardiovascular deaths (0.7% vs. 4.3%, p = 0.015), and all-cause deaths (1.3% vs. 5.7%, p = 0.018) were similarly less frequent in those with LVRR.

CONCLUSIONS

LVRR after AFCA, which was predicted by non-paroxysmal AF without any apparent structural heart disease at baseline, was associated with persistent form of AF recurrence prior to the evaluation. LVRR was associated with favorable clinical outcomes.

Validation of the HFA-PEFF- and H2FPEF score in Japanese patients with heart failure with preserved ejection fraction

Background

Diagnosing heart failure with preserved ejection fraction (HFpEF) still remains challenging, and simple and reliable diagnostic tools have been required. Recently, novel and evidence-based diagnostic algorithms for HFpEF were proposed, such as H2FPEF score (Circulation. 2018) and HFA-PEFF score (Eur Heart J 2019), and their accuracy was validated in the outside patient group. However, there are regional and ethnic variations in patient characteristics of HFpEF, particularly between Western and Asian countries, and it is not elucidated whether these diagnostic scores are useful in Asian population.

Purpose

To investigate the validity of the HFA-PEFF- and H2FPEF score in Japanese patients with HFpEF.

Methods

We calculated H2FPEF score and the second step of HFA-PEFF score among the registered patients in the PURSUIT-HFpEF (Prospective, Multicenter, Observational Study of Patients with Heart Failure with Preserved Ejection Fraction) study, which is a multicenter registration of patients hospitalized for HFpEF. The obtained scores were compared with the scores of the HFpEF cohort in the previous validation studies. We followed the study patients for median of 360 days (IQR 237–630 days) to observe the major adverse cardiovascular events (MACE; composite of death, heart failure hospitalization and stroke).

Results

We enrolled 757 patients hospitalized for HFpEF between June 2016 and August 2019 for the present study. H2FPEF score was obtained in 588 (77.7%) patients among them. Compared with the HFpEF cohorts in the previously reported sub-analysis of TOPCAT trial, the PURSUIT-HFpEF cohort had lower mean value of HFpEF score (4.0±1.8 points vs. 6.0±2.0 points in Americans or 5.3±1.9 points in Russians). It had significantly higher proportion (40.3%, p&lt;0.001) of patients in the low likelihood of HFpEF category (0–3 points) than the TOPCAT cohorts (8.0% in Americans and 19.6% in Russians).

HFA-PEFF score was obtained in 615 (81.2%) patients, though global longitudinal strain was not available. The mean value of HFA-PEFF score was 5.0±0.8, and all patients had ≥2 points. The proportion of patients in the high likelihood of HFpEF category (5–6 points) was 88.3%, which was significantly higher (p&lt;0.001) than those of the HFpEF cohort from Europe and USA in the previous validation study (Eur J Heart Fail 2019). There was no correlation between H2FPEF score and HFA-PEFF score (R=0.06, p=0.14). Cox proportional hazard model selected HFA-PEFF score as a significant predictor for MACE during follow-up period, whereas H2PEF score was not selected. Kaplan-Meier survival analysis demonstrated that patients with 6 points of HFA-PEFF score had higher incidence rate of MACE than those with ≤5 points (p=0.002).

Conclusion

The HFA-PEFF score could be more useful for the diagnosis and risk stratification for HFpEF than the H2PEF score in the Japanese cohort.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Roche Diagnostics K.K.; Fuji Film Toyama Chemical Co. Ltd.

High incidence of left atrial dysfunction and low voltage zone in patients requiring multiple atrial fibrillation ablation

Background

While multiple catheter ablation for recurrent atrial fibrillation (AF) is effective for the maintenance of sinus rhythm, some of patients have ablation-refractory AF. Left atrial (LA) dysfunction and the presence of low voltage zone (LVZ) are associated with recurrence after AF ablation. The association between recurrence and LA dysfunction/ LVZ among patients undergoing multiple AF ablation remains unclear.

Purpose

We aimed to compare (i)LA function, (ii)the prevalence of LVZ among patients undergoing first, second and third or more AF ablation procedures. Further, we investigated whether LA dysfunction and LVZ are associated with recurrence after multiple procedures.

Methods

We retrospectively analyzed 460 patients undergoing AF ablation procedures including first, second and third or more sessions from January 2017 to October 2019 in our institute. Before each session, 256-slice MDCT was performed under sinus rhythm to measure pre-ablation LA emptying fraction (LAEF) as the representative of LA function. At the end of each session, we checked the presence of LVZ, which was defined as regions where bipolar peak-to-peak voltage was &lt;0.5mV. All patients underwent pulmonary vein isolation (PVI). If necessary, additional ablation (e.g. linear ablation, non-PV foci ablation and LVZ ablation) was performed.

Results

Out of 460 sessions, 295 were first (follow-up years: 1.5 [0.8, 2.0]), 134 were second (1.0 [0.5, 1.8]), and 31 were third or more sessions (1.2 [0.7, 2.0]). As the number of sessions increased, the recurrence rate was increased (19% vs. 31% vs. 61%, first vs. second vs. ≥third, P&lt;0.0001), LAEF decreased (39.7±10.5% vs. 32.6±10.1% vs. 25.3±11.8%, P&lt;0.0001) and the incidence of LVZ increased (18% vs. 34% vs. 68%, P&lt;0.0001) (Figure 1). In patients with recurrence (N=104) after multiple ablation (second or more sessions), LAEF was lower and the prevalence of LVZ was higher than those without recurrence (N=61) (LAEF: 27.3±10.3% vs. 33.5±10.5%, with vs. without, P=0.0003; LVZ: 57% vs. 31%, P=0.0014).

Conclusions

As the number of sessions increased, the recurrence rate was increased. The prevalence of LA dysfunction and LVZ was high in patients requiring multiple ablation procedure. LA dysfunction and LVZ possibly reflect arrhytmogenic substrate causing recurrence of ablation-refractory AF. We should carefully consider repeated AF ablation in patients with severe LA dysfunction and extensive LVZ.

Figure 1

Funding Acknowledgement

Type of funding source: None

Pre-ablation left atrial function predicts the presence of low voltage zone in patients undergoing paroxysmal atrial fibrillation ablation: OLAF-LVZ predictive score

Background

Preoperative left atrial (LA) function is associated with paroxysmal atrial fibrillation (PAF) ablation outcome. The presence of left atrial low voltage zone (LVZ) is also associated with recurrence. We hypothesized that reduced pre-ablation LA function reflects the presence of LVZ.

Purpose

We investigated the association between baseline LA function and the presence of LVZ in patients undergoing initial PAF ablation. Further, we sought to create the new predictive scoring for the presence of LVZ.

Methods

Consecutive 305 patients who underwent LA voltage mapping during initial PAF ablation from January 2017 to October 2019 in our institute were retrospectively analyzed. We performed 256-slice MDCT at baseline. As the representative of LA function, we calculated LA emptying fraction (LAEF), where LAEF = {[(maximum LAV) − (minimum LAV)]/(maximum LAV)} x 100. LVZ was defined as regions where bipolar peak-to-peak voltage was &lt;0.5mV. We performed the univariate and multivariate analysis to assess the association between LAEF and the presence of LVZ. Second, we performed receiver operating characteristic (ROC) analysis for the prediction of LVZ. We combined multivariate predictors and created the predictive scoring for LVZ.

Results

Out of 305 pts, 56 pts (18%) had LVZ in LA. In univariate analysis, low body mass index, higher percentage of female sex, higher age, higher E/e', larger maximum LA volume and lower LAEF (29.3±11.8% vs. 41.2±9.7, P&lt;0.0001) was associated with the presence of LVZ. In multivariate logistic regression analysis, Low LAEF revealed the strongest predictor for LVZ (LAEF; Odds ratio [OR]/10% increase: 0.54, 95% CI: 0.39–0.82, P=0.0016). High age and female sex also remained as the independent predictors (Age; OR/10 y.o. increase: 1.80, 1.23–3.03, P=0.0042, Female; OR: 2.51, 1.15–5.49, P=0.0213). In ROC analysis, LAEF had moderate predictive accuracy for the presence of LVZ. (Area under the ROC curve: 0.77, Best cut-off value: 31%, P&lt;0.0001) (Figure 1). We created OLAF-LVZ predictive score by combining Old age (1 point, ≥65), LAEF (2 points, LAEF ≤31%) and Female sex (1 point). OLAF score had gradient effect on the incidence of LVZ (2%, 11%, 25%, 45%, 71%, OLAF score; 0, 1, 2, 3, 4, respectively, P&lt;0.0001) (Figure 2).

Conclusions

In PAF patients, preoperative LAEF was strongly associated with the presence of LVZ. LVZ might reflect the myocardial injury causing LA dysfunction. OLAF-LVZ predictive score: combination of Old age (≥65), Female sex, and LAEF (≤31%) could be useful to stratify the risk of the presence of LVZ.

Funding Acknowledgement

Type of funding source: None

Quantitative analysis of dyssynchrony assessed by multidetector computed tomography can predict clinical outcome after cardiac resynchronization therapy

Background

The degree of mechanical dyssynchrony has been suggested as a predictor for long-term survival after cardiac resynchronization therapy (CRT). There have been little reports of dyssynchrony assessment with the use of cardiac computed tomography (CCT).

Methods

We studied 35 heart failure (HF) patients (average age 67±10 years) referred for CRT with NYHA III-IV heart failure, left ventricular (LV) ejection fraction (EF) 20±10% (all ≤35%), and QRS duration 156±22 ms (all ≥120ms). Electrocardiogram-gated contrast-enhanced 256-slice multidetector CT was performed before CRT. Based on CCT, the LV endocardial boundaries from short-axis images reconstructed at 5% increments of cardiac cycle were automatically detected, and the time from R-wave to maximal wall motion was calculated for each of the 16 standardized segments for all slices using software “Myocardial Contraction Map”. The standard deviation modified by mean heart rate (%SD) was respectively calculated as the global parameter of dyssynchrony. LVEF was also measured using MDCT. The predefined primary end-point was the first HF hospitalization or death over 2 years.

Results

%SD was feasible in all patients, respectably. There were 16 events over 2 years; 11 HF hospitalizations and 5 deaths. Patients with %SD ≥22% (optimal cutoff for outcome by ROC curve analysis) had a better clinical outcome than patients with %SD &lt;22% (p=0.01, Figure).

Conclusion

Patients who had %SD ≥22% assessed by MDCT had a particularly favorable event-free survival following CRT, and this appears to be an important prognostic marker.

Funding Acknowledgement

Type of funding source: None

Evaluation of the local atrial function by regional speckle tracking imaging using intracardiac echocardiography

Background

It has been reported that low voltage areas and conduction abnormalities detected by electrophysiology catheters in the left atrium (LA) represent regional degeneration and fibrosis of the atrium and are related to a poor atrial fibrillation (AF) ablation outcome. Assessment of the local atrial function is clinically useful because atrial degeneration does not occur uniformly throughout the atrium. Though evaluating the global atrial function using speckle tracking imaging (STI) by transthoracic echocardiography (TTE) has been attempted, TTE does not have a sufficient image quality to assess local atrial STI.

Purpose

To evaluate the local atrial function by STI using intracardiac echocardiography (ICE) and to elucidate the characteristics of the STI in normal and abnormal voltage regions in the LA.

Methods

We included 9 patients undergoing AF ablation with written informed consent for this prospective observational study. After pulmonary vein isolation, we performed voltage mapping of the LA in sinus rhythm using a CARTO system (Biosense). Abnormal regions and normal regions were defined as those with low voltage areas (&lt;0.5 mV) and those with normal voltages, respectively. Echo images were recorded by an ACUSON SC2000 (Siemens) and SOUNDSTAR catheter (Biosense). We inserted the SOUNDSTAR catheter into the LA to obtain clear images, recorded the STI of the anterior and inferior wall, and performed an offline analysis of the atrial strain with an eSie VVI work station (Siemens) and the LA voltage data with CARTO system at each site simultaneously (left figure). We compared the strain during the atrial contraction phase (Sct) between the normal and abnormal regions.

Results

Among the study population, 5 patients had low voltage areas in the LA. We evaluated the STI at 26 normal regions and 44 abnormal regions. The typical regional speckle tracking waveform in the normal region was similar to a jugular vein pressure waveform (right figure). There was a difference in the amplitude of the Sct between the groups; it was significantly smaller in the abnormal regions (normal and abnormal regions, 9.8±5.0% and 5.6±3.8%, p=0.0001). The duration of the Sct was significantly more prolonged in the abnormal regions than normal regions (98.8±26.3ms and 118.2±33.9ms, p=0.015).

Conclusions

This pilot study demonstrated that the local atrial function was evaluable by STI using ICE and that the regional strain tracking waveform during the atrial contraction phase in abnormal voltage regions was smaller and more prolonged than that in normal regions. An evaluation of the regional STI with an ICE may be useful to detect regional abnormalities of the atrium.

Representative case

Funding Acknowledgement

Type of funding source: None

Calcified Nodules in the Superficial Femoral Artery Confirmed by Intravascular Ultrasound, Angioscopy, and Histology

An 84-year-old man was admitted to the authors' hospital for the treatment of intermittent claudication. Angiography revealed an exophytic calcified nodules in the distal superficial femoral artery. Angioscopy also revealed abundant exophytic atherosclerotic calcification. Histology confirmed the diagnosis. (Level of Difficulty: Beginner.).

Early recurrence during the blanking period and left atrial reverse remodeling after catheter ablation for non-paroxysmal atrial fibrillation

Background

Early recurrence of atrial tachyarrhythmia (ERAT) during a 90-day blanking period (BP) often occurs after atrial fibrillation (AF) ablation. Left atrial reverse remodeling (LARR), which is the reduction in LA volume (LAV), also occurs during the BP. Both ERAT and LARR are associated with late recurrence (LR, greater than 90 days after ablation). We investigated the association between ERAT and LARR following non-paroxysmal AF (NPAF) ablation.

Methods

We retrospectively reviewed 330 consecutive patients undergoing initial NPAF ablation (median follow-up: 4.0 years). Based on the timing of the final ERAT, we divided the patients into No-ERAT (N = 154, without ERAT), Early (N = 39, 0–7 days after ablation), Intermediate (N = 67, 8–30), and Late-ERAT (N = 70, 31–90) groups. We assessed the extent of LARR, defined as the percentage of decrease in LAV (%ΔLAV). The %ΔLAV cutoff value was determined by receiver operating characteristic analysis, and incorporated into a multivariate analysis to assess the association between ERAT and LARR.

Results

Late-ERAT was associated with LR (hazard ratio: 6.31, 95% confidence interval (CI): 4.21–9.47, p = 0.0001). The %ΔLAV in the Late-ERAT group was significantly smaller than the other groups (p < 0.0001). The predictive power of %ΔLAV for LR was slight (AUC, 0.604; best cutoff, 18.8% decrease; p = 0.0011). In the multivariate logistic regression analysis, Late-ERAT was associated with poor LARR (%ΔLAV < 18.8% decrease) (odds ratio, 0.13; 95%CI, 0.06–0.27; p < 0.001), whereas Early- and Intermediate-ERAT did not show any correlation.

Conclusions

Late-ERAT was strongly associated with poor LARR after NPAF ablation. Both Late-ERAT and poor LARR might reflect a residual arrhythmogenic substrate causing LR.

Anti-allergic effect of the Src family kinase inhibitor saracatinib

The aim of this study was to evaluate the anti-anaphylactic and anti-allergic potentials of saracatinib, a Src family kinase inhibitor that was already shown to be safe in clinical trials when it was used as an anti-cancer drug. Using in vitro mast cell models, we found that saracatinib inhibited the degranulation response and cytokine production in RBL2H3 cells that were stimulated with IgE and antigen without affecting cell viability. Phosphorylation of Lyn, Akt, a PI3K substrate, and MAPKs including ERK, JNK, and p38, as well as the intracellular Ca²⁺ increase induced by this stimulation were also suppressed by saracatinib. This drug also inhibited symptoms in our established anaphylaxis mouse model, anaphylaxis-dependent spotted distribution of immune complex in skin (ASDIS). The intravenous injection of the mixture of IgE and antigen induced acute spotted distribution of immune complex in skin in hairless HR-1 mice, and its inhibition by intradermal injection of saracatinib was observed. Moreover, toluidine blue-stained skin sections indicated that the degranulation ratio of dermal mast cells was reduced in saracatinib-treated skin compared with vehicle-treated skin. Because only a few signaling inhibitors are used as anti-anaphylaxis and anti-allergic drugs, these results indicated the valuable suggestion that saracatinib and the Src family kinase inhibitors are good candidates for anti-anaphylaxis and anti-allergic drugs.

Use of vertebral left atrial size for staging of dogs with myxomatous valve disease

INTRODUCTION/OBJECTIVES

The American College of Veterinary Internal Medicine (ACVIM) guidelines suggest that pimobendan should be initiated in dogs which meet all criteria of stage B2 myxomatous mitral valve disease (MMVD): murmur intensity ≥ 3/6, left atrial-to-aortic ratio ≥ 1.6, normalized left ventricular internal diameter in diastole ≥ 1.7, and vertebral heart size > 10.5. Recently, a new radiographic index for left atrial enlargement, vertebral left atrial size (VLAS), was proposed. The objective of the present study was to evaluate whether VLAS is useful in staging MMVD and if it can distinguish between ACVIM stages B1 and B2.

ANIMALS

Ninety-seven client-owned dogs with MMVD were evaluated and classified as ACVIM stage B1, B2, or C-D.

MATERIALS AND METHODS

The echocardiographs and radiographs of all the dogs were retrospectively evaluated to obtain left atrial-to-aortic ratio, normalized left ventricular internal diameter in diastole, and VLAS values. The data were analyzed to assess the correlation between these measurements and VLAS, and the optimal cutoff value of VLAS was determined.

RESULTS

A VLAS cutoff value of 2.6 provided the greatest diagnostic accuracy for identification of dogs with ACVIM stage B2 MMVD (area under the curve, 0.96; sensitivity, 95%; specificity, 84%). A VLAS ≥2.5 exhibited the highest sensitivity (sensitivity, 100%; specificity, 78%), and a VLAS ≥ 3.1 exhibited the highest specificity (sensitivity, 47%; specificity, 100%).

CONCLUSIONS

VLAS is a helpful index for monitoring MMVD using radiography. A VLAS cutoff value of 2.5 could be used to identify dogs that may benefit from echocardiography to determine if they have reached ACVIM stage B2.

SAT0119 PARADOXICAL NEUTROPHIL ACTIVATION BY ANTI-IL6 THERAPY: TRANSCRIPTOME ANALYSIS SHOWS A RATIONALE FOR DERMATOLOGICAL ADVERSE REACTIONS AND DECREASED NEUTROPHIL COUNTS AFTER TOCILIZUMAB TREATMENT

Background:

Skin rashes as a side effect of Tocilizumab therapy (TCZ- Tx) has not been paid much attention, because the incidence was only 1~2% in the drug information sheets. However, we experienced several RA cases with development of various skin rashes associated with neutrophil activation after TCZ-Tx. On the other hand, it is well known that the neutrophil counts in peripheral blood decreases after TCZ-Tx, whereas it does not affect the rate of serious infections. The detailed mechanism is still unclear.

Objectives:

To detect the characteristics of the changes in gene expressions of peripheral blood associated with TCZ-Tx and the development of skin rashes as its side effect.

Methods:

Total of 14 RA patients with TCZ-Tx were included. Among them, 4 patients developed TCZ-related rashes (group S) and 10 patients did not show any side effects (group C). Peripheral whole blood at just before (pre) and 3 months after (post) TCZ-Tx from each patient were subjected to the analysis. Total RNAs were extracted with PAXgene miRNA kit and analyzed with next-generation sequencing. First, group C was investigated for the normal response to TCZ-Tx. Differentially expressed genes (DEGs) were selected by paired comparison (post vs. pre). And then, enrichment analysis using gene ontology (GO) terms were performed. Second, to explore the characteristics of group S, all expressed genes in 14 cases at just before TCZ-Tx were subjected to a hierarchical clustering analysis. The DEGs (group S vs. C and post vs. pre) were also investigated with weighted gene co-expression network analysis (WGCNA) and GO analysis. Meanwhile, the total eigengene expressions of the important modules identified by WGCNA in each cases were also calculated.

Results:

Surprisingly, 8 out of the top 10 enriched GO terms in the up-regulated genes were relevant to leukocyte activation such as ‘neutrophil migration” by the analysis of DEGs (post vs. pre) in group C. The cluster analysis of ‘pre’ genes confirmed that the patterns of gene expression between group S and C was different. WGCNA analysis of DEGs (group S vs. C) revealed that genes related to acute inflammation such as ‘leukocyte mediated immunity’ were activated in group S. Interestingly, it was not correlated with disease activity score (DAS) of RA. By the analysis of DEGs (post vs. pre) of upregulated genes, we found that the total eigengene expressions of the module enriched with genes related to ‘cell adhesion’ or ‘leukocyte migration’ were significantly increased in all cases of group S.

Conclusion:

This is the first evidence that the genes associated with neutrophil migration is significantly activated after TCZ-Tx. It is noteworthy that the gene activation was observed in cases without any side effects. The decreased neutrophil counts in peripheral blood have been known after initiation of TCZ-Tx, which did not affect the rate of serious infections. Recently, It was reported that TCZ affects neutrophil trafficking to the bone marrow1). Our findings will provide a rationale for its cause. On the other hand, we experienced several RA cases with development of various skin rashes associated with neutrophil activation after TCZ-Tx. However, majority of patients do not develop the side effect, even though genes related to ‘neutrophil migration’ are activated. In group S, our findings indicate that the genes related to ‘leukocyte mediated immunity’ was already activated at the initiation of treatment without correlating to DAS of RA, furthermore, the gene upregulation related to ‘leukocyte migration’ was more prominent after TCZ-Tx. Although it is difficult to predict the patients developing skin rashes before TCZ-Tx, we do not recommend to use TCZ for the patients with neutrophilic dermatosis which is often associated with RA.

References: :

[1]Lok LSCet al.,Eur J Clin Invest. 47(10):736-745 (2017).

Disclosure of Interests: :

Moe Sakamoto: None declared, Akemi Senoh: None declared, Yoshiharu Sato: None declared, Hiroshi Iijima: None declared, Mari Yamaguchi: None declared, Toshie Higuchi: None declared, Yoshinobu Koyama Grant/research support from: Eli-Lilly and Mochida., Speakers bureau: BMS, Ayumi, Chugai, Ono, Mitsubishi Tanabe, Abbvie and Eisai.

THU0208 AFFECTING COMMON BIOLOGICAL PROCESSES OR DISPARATE?: COMPARISON OF GENE-EXPRESSION MODIFICATION PROFILES AMONG TARGETING IL-6 AND TARGETING SPECIFIC JAK TREATMENTS

Background:

After accumulation of evidences, it is recognized that inhibition of IL-6 signaling is one of the most established strategies for rheumatoid arthritis (RA) treatment. Tocilizumab (TCZ), an anti-IL6 receptor monoclonal antibody, is the pioneer which blocks IL-6 signaling by preventing IL-6 from binding to both membrane-bound and soluble receptors. Tofacitinib (TOF) inhibits Janus kinase (JAK) 1, JAK3 and, to a lesser extent, JAK2. Recently, Baricitinib (BAR), JAK 1 and JAK2 selective kinase inhibitor, were also approved to treat RA. These JAK inhibitors are known to inhibit cytokine signaling including interleukin (IL)-6. It is very important for clinicians to know whether these treatments affect common biological processes or disparate, because it will provide a rationale for switching each other if one of these treatments resulted in lack of efficacy.

Objectives:

To compare the gene-expression modification profiles among TOF, BAR and TCZ treatments.

Methods:

Total of 38 RA cases were analyzed, including TOF (n=15: 6-20mg/d), BAR (n=10: 2-4mg/d) and TCZ (n=13: 8mg/kg/4w or 163mg/2w) treatment groups. Peripheral blood was drawn at just before (pre) and 3 months after (post) these treatments. Total RNAs were then extracted with using PAXgene miRNA kit. After constructing single-stranded, strand-specific libraries, multiplex sequencing was done. After quantifying the expressions of transcripts, differentially expressed genes (DEGs) were selected by paired comparison (post vs. pre), setting thresholds at 2-fold change up/down and less than P=0.05 in paired T-test. And then, hierarchical clustering analysis and enrichment analysis using gene ontology (GO) terms were performed.

Results:

From the comparison of post- vs. pre-treatment of TOF, BAR and TCZ, the 120 (up-regulated=25/down-regulated=95), 62 (up=20/down=42) and 193 (up=54/ down=139) genes were selected as DEGs respectively. It seems to be discrete depending on the treatment, because overlapped genes were only 1.0% in up-regulated and 5.7% in down-regulated genes. The hierarchical clustering with expression profiles of these DEGs showed major 4 clusters. 92.3% of TCZ and 70% of BAR cases were segregated into 1stand 3rdclusters respectively, while those of TOF cases fell into 2ndand 4thclusters. Disparate GO terms were enriched in each DEGs group. For example, genes relevant to viral defense including ‘response to type I interferon (IFN)’ were suppressed in TOF group. Meanwhile, down regulation of genes involved in phosphorylation process including ‘IL-7 signaling’ seemed to be significant in BAR group. It is noteworthy that terms related to wound healing such as ‘platelet activation’ were enriched in the down-regulated genes of TCZ group.

Conclusion:

It is speculated that the downstream biological cascade for TOF, BAR and TCZ treatment might be shared, as IL-6 signaling is mediated by JAK1/JAK2/TYK2 activation. However, the influence of these treatments over the transcriptome in the peripheral blood seems to be disparate. Enrichment analysis using GO terms also indicated that different biological processes were involved in the effect of each treatment. Our findings will support a rationale for switching each other if one of these treatments resulted in lack of efficacy. An increased risk of herpes zoster by a treatment with JAK inhibitors has been well recognized. It makes sense because IFN signaling is also mediated by JAK/STAT pathway. On the other hand, we have experienced a case with exacerbation of skin ulcer during TCZ treatment despite the activity of RA was absolutely under control. It is accounted for by the suppression of genes involved in wound healing after TCZ treatment.

Disclosure of Interests: :

Yoshinobu Koyama Grant/research support from: Eli-Lilly and Mochida., Speakers bureau: BMS, Ayumi, Chugai, Ono, Mitsubishi Tanabe, Abbvie and Eisai., Yoshiharu Sato: None declared, Moe Sakamoto: None declared, Hiroshi Iijima: None declared, Toshie Higuchi: None declared