Clinical impact of left atrial remodeling pattern in patients with atrial fibrillation: Comparison of volumetric, electrical, and combined remodeling.

INTRODUCTION: Atrial fibrillation (AF) is accompanied by various types of remodeling, including volumetric enlargement and histological degeneration. Electrical remodeling reportedly reflects histological degeneration. PURPOSE: To clarify the differences in determinants and clinical impacts among types of remodeling. METHODS: This observational study included 1118 consecutive patients undergoing initial ablation for AF. Patients were divided into four groups: minimal remodeling (left atrial volume index [LAVI] < mean value and no low-voltage area [LVA], n = 477); volumetric remodeling (LAVI ≥ mean value and no LVA, n = 361); electrical remodeling (LAVI < mean value and LVA presence, n = 96); and combined remodeling (LAVI ≥ mean value and LVA presence, n = 184). AF recurrence and other clinical outcomes were followed up for 2 and 5 years, respectively. RESULTS: Major determinants of each remodeling pattern were high age for electrical (odds ratio = 2.32, 95% confidence interval = 1.68-3.25) and combined remodeling (2.57, 1.88-3.49); female for electrical (3.85, 2.21-6.71) and combined remodeling (4.92, 2.90-8.25); persistent AF for combined remodeling (7.09, 3.75-13.4); and heart failure for volumetric (1.71, 1.51-2.53) and combined remodeling (2.21, 1.30-3.75). Recurrence rate after initial ablation increased in the order of minimal remodeling (20.1%), volumetric (27.4%) or electrical remodeling (36.5%), and combined remodeling (50.0%, p < .0001). A composite endpoint of heart failure, stroke, and death occurred in the order of minimal (3.4%), volumetric (7.5%) or electrical (8.3%), and combined remodeling (15.2%, p < .0001). CONCLUSION: Volumetric, electrical, and combined remodeling were each associated with a unique patient background, and defined rhythm and other clinical outcomes.

Impact of diabetes mellitus and poor glycemic control on the prevalence of left atrial low-voltage areas and rhythm outcome in patients with atrial fibrillation ablation.

INTRODUCTION: Left atrial low-voltage areas (LVAs) are known to be correlated with atrial scarring and atrial fibrillation (AF) recurrence after ablation. However, the association between LVAs and glycemic status before ablation has not been fully clarified. The purpose of this study was to investigate associations among the prevalence of diabetes mellitus (DM), glycemic control, and the prevalence of LVAs in patients with AF ablation. METHODS: In total, 912 (age, 68 ± 10 years; female, 299 [33%]; persistent AF, 513 [56%]) consecutive patients who underwent initial AF ablation were included. A preprocedure glycated hemoglobin A1c (HbA1c) ≥7% was set as the cutoff for poor glycemic control in patients with DM. LVAs were defined as areas with a bipolar voltage of <0.5 mV covering ≥5 cm2 of left atrium. RESULTS: LVAs existed in 208 (23%) patients, and 168 (18%) patients had DM. LVAs were found more frequently in patients with DM and poor glycemic control. On multivariate analysis, DM with HbA1c ≥7% was an independent predictor of LVAs (odds ratio, 3.3; 95% confidence interval: 1.6-6.7; p = .001). In patients with LVAs, freedom from AF recurrence during the 24-month study period was significantly lower in patients who had DM with HbA1c ≥7% than in those without DM (37.9% vs. 54.7%, p = .02). CONCLUSION: In patients with AF ablation, LVAs were found more frequently in patients with DM and poor glycemic control. DM with HbA1c ≥7% was an independent predictor of LVAs.

Impact of Procedural Techniques on Midterm Patency of Fluoropolymer-Based Drug-Eluting Stent Placed in the Femoropopliteal Artery.

PURPOSE: To investigate the impact of compliance with recommended procedural techniques on the midterm patency of a fluoropolymer-based drug-eluting stent (FP-DES) in the femoropopliteal artery. MATERIALS AND METHODS: This retrospective study included 200 femoropopliteal lesions (chronic limb-threatening ischemia, 59%; chronic total occlusion, 41%) in 173 patients (male, 66%; diabetes mellitus, 62%; hemodialysis, 40%) with lower extremity arterial disease who underwent intravascular ultrasound (IVUS)-guided endovascular therapy with FP-DES between January 2016 and July 2021. The primary outcome measure was restenosis, defined as a peak systolic velocity ratio of >2.4 based on the duplex US findings. The association between procedural techniques and incidence of restenosis was investigated using Cox proportional hazards regression models. RESULTS: The 2-year cumulative incidence of restenosis was 19.5% (SD ± 3.3). Multivariate analysis revealed that noncompliance with recommended procedural techniques, such as plaque burden at the stent edge of <50%, a minimum stent area (MSA) of >12 mm2, and stent placement within the P1 segment, was independently associated with an increased risk of restenosis (hazard ratios [HRs], 3.22, 4.71, and 4.67 and P = .004, P < .001, and P < .001, respectively). The 2-year restenosis risk for procedures performed in compliance with all 3-technical criteria was 8.4% (SD ± 3.4), whereas the risks for those in compliance with 2-technical criteria or 0- or 1-technical criteria were 25.0% (SD ± 6.2) and 48.6% (SD ± 10.4), respectively. HRs relative to 3-technical criteria compliance were 3.79 (P = .007) and 11.85 (P < .001), respectively. CONCLUSIONS: Noncompliance with recommended procedural techniques, including plaque burden at the stent edge of <50%, MSA of >12 mm2, and stent placement within the P1 segment, was significantly associated with an increased risk of 2-year restenosis after FP-DES implantation in the femoropopliteal artery.

Impact of wall thickness on the tissue cooling effect of cryoballoon ablation.

AIMS: Understanding of the tissue cooling properties of cryoballoon ablation during pulmonary vein (PV) isolation is lacking. The purpose of this study was to delineate the depth of the tissue cooling effect during cryoballoon freezing at the pulmonary venous ostium. METHODS AND RESULTS: A left atrial-PV model was constructed using a three-dimensional printer with data from a patient to which porcine thigh muscle of various thicknesses could be affixed. The model was placed in a 37°C water tank with a PV water flow at a rate that mimicked biological blood flow. Cryofreezing at the PV ostium was performed five times each for sliced porcine thigh muscle of 2, 4, and 6 mm thickness, and sliced muscle cooling on the side opposite the balloon was monitored. The cooling effect was assessed using the average temperature of 12 evenly distributed thermocouples covering the roof region of the left superior PV. Tissue cooling effects were in the order of the 2, 4, and 6 mm thicknesses, with an average temperature of -41.4 ± 4.2°C for 2 mm, -33.0 ± 4.0°C for 4 mm, and 8.0 ± 8.7°C for 6 mm at 180 s (P for trend <0.0001). In addition, tissue temperature drops were steeper in thin muscle (maximum temperature drop per 5 s: 5.2 ± 0.9°C, 3.9 ± 0.7°C, and 1.3 ± 0.7°C, P for trend <0.0001). CONCLUSION: The cooling effect of cryoballoon freezing is weaker in the deeper layers. Cryoballoon ablation should be performed with consideration to myocardial thickness.

Comparison of voltage maps using OCTARAY catheter and PENTARAY catheter.

BACKGROUND: Recently, a new OCTARAY® mapping catheter was commercially launched. The catheter is designed to enable high-density mapping and precise signal recording via 48 small electrodes arranged on eight radiating splines. The purpose of this study was to compare bipolar voltage and low-voltage-area size, and mapping efficacy between the OCTARAY catheter and the PENTARAY® catheter METHODS: Twelve consecutive patients who underwent initial and second ablations for persistent atrial fibrillation within 2 years were considered for enrollment. Voltage mapping was performed twice, first during the initial ablation using the PENTARY catheter and second during the second ablation using the OCTARAY Long 3-3-3-3-3 (L3) catheter. RESULTS: Mean voltage with the OCTARAY-L3 catheter (1.64 ± 0.57 mV) was 32.3% greater than that with the PENTARAY catheter (1.24 ± 0.46 mV, p < .0001) in total left atrium. Low-voltage-area (<0.50 mV) size with the OCTARAY-L3 catheter was smaller than that with the PENTARAY catheter (6.9 ± 9.7 vs. 11.4 ± 13.0 cm2 , p < .0001). The OCTARAY-L3 catheter demonstrated greater efficacy than the PENTARAY catheter in terms of shorter mapping time (606 ± 99 vs. 782 ± 211 s, p = .008) and more mapping points (3,026 ± 838 vs. 781 ± 342 points, p < .0001). CONCLUSION: The OCTARAY catheter demonstrated higher voltage recordings, narrower low-voltage areas, and a more efficacious mapping procedure than the PENTARAY catheter.

Impact of calcified nodule on target lesion failure after stent implantation in hemodialysis patients.

BACKGROUND: Little is known about intravascular imaging predictors of cardiac events after drug-eluting stent (DES) implantation in hemodialysis (HD) patients. We aimed to reveal the association between calcified nodules (CN) and target lesion failure (TLF) in HD patients after DES implantation. METHODS: We enrolled 114 HD patients who underwent DES implantation between October 2016 and October 2020. The patients were divided into a CN group (39%, 44 patients) and a non-CN group (61%, 70 patients). The primary endpoint was the incidence of TLF, including cardiac death, target vessel myocardial infarction, and clinically driven target lesion revascularization. RESULTS: HD duration was longer, and the calcium burden was higher in the CN group than in the non-CN group. Over a median follow-up of 607 days [interquartile range: 349-965 days], the cumulative incidence curve showed that the CN group had a significantly higher incidence of TLF than the non-CN group (31.8% vs. 11.4% within 3 years, p = 0.008).　On Fine-Gray sub-distribution hazard model analysis, the CN group was associated with an increased rate of TLF (hazard ratio [HR]: 2.86; 95% confidence interval [CI]: 1.21-6.75, p = 0.016). An in-stent CN was observed in 73% of the lesions with target lesion revascularization in the CN group, whereas no in-stent CN was observed in the non-CN group (p = 0.026). CONCLUSIONS: CN was an independent predictor of TLF in patients undergoing HD. In-stent CN was an important cause of TLF after DES implantation in CN lesions in HD patients; therefore, a different strategy should be considered for treating the lesions.

Angiographic patterns of restenosis after drug-coated balloon angioplasty for femoropopliteal lesions and 1-year prognosis after repeat endovascular therapy.

AIM: The aim of the current study sought to investigate the angiographic patterns of restenosis after drug-coated balloon (DCB) angioplasty for femoropopliteal (FP) lesions and which repeat endovascular therapy (EVT) for DCB restenosis would provide more freedom from recurrent restenosis. METHODS: This retrospective multicenter study included 119 limbs (chronic limb-threatening ischemia [CLTI]: 55%, lesion length: 136.9 ± 89.6 mm, chronic total occlusion: 25%) of 95 patients (diabetes mellitus: 70%, hemodialysis: 56%) who were diagnosed with DCB restenosis between January 2018 and December 2019. The cases were classified into three groups based on angiographic patterns of restenosis: Class I: focal lesions ≤50 mm, Class II: diffuse lesions >50 mm, and Class III: totally occluded lesions. The DCB restenosis patterns and frequency and predictors of recurrent restenosis after repeated EVT (re-EVT) were investigated. RESULTS: The mean follow-up duration was 29.8 ± 9.5 months. Groups I, II, and III comprised of 30 (25.2%), 55 (46.2%), and 34 (29.0%) cases, respectively. The overall rate of 1-year freedom from recurrent restenosis was 58.2%. One-year rate of freedom from recurrent restenosis after repeat DCB was not statistically different from that after scaffolding (71.1% vs. 74.6%, respectively, p = 0.911); however, it was significantly better than that after noncoated balloon angioplasty (repeat DCB vs. noncoated balloon angioplasty: 71.1% vs. 25.7%, respectively, p < 0.001). Multivariate analysis demonstrated that CLTI (hazard ratio [HR]: 5.15, p < 0.001) and re-EVT with noncoated balloon (HR: 3.16, p < 0.001) were significantly associated with recurrent restenosis; however, Class III pattern of DCB restenosis was not associated with recurrent restenosis (HR: 1.04, p = 0.918). CONCLUSIONS: This study revealed the angiographic patterns of restenosis after DCB therapy for FP lesions and the 1-year rate of recurrent restenosis after repeat revascularization. Repeat DCB therapy demonstrated acceptable 1-year recurrent restenosis rates.

Impact of Cardiac Function on Loss of Patency in Patients With Peripheral Artery Disease Presenting the Femoropopliteal Lesions Endovascularly Treated With New-Generation Devices.

PURPOSE: The current study sought to investigate the impact of cardiac condition on loss of patency after endovascular therapy (EVT) using new-generation devices for femoropopliteal (FP) lesions. MATERIALS AND METHODS: We retrospectively studied 547 lesions (chronic limb-threatening ischemia: 44%, TASC II C/D lesion: 61%, chronic total occlusion: 37%, in-stent restenosis: 13%, involving popliteal arterial lesion: 45%) belonging to 416 patients (average age: 75±9 years, male: 69%, diabetes mellitus: 62%, hemodialysis: 33%) who underwent EVT with new-generation FP-specific devices (polymer-free paclitaxel-eluting stent, n=186; stent graft, n=119; fluoropolymer-based paclitaxel-eluting stent, n=29; interwoven stent, n=17; drug-coated balloon, n=196) from June 2012 to May 2019. Cardiac function was evaluated using echocardiography. The primary outcome measure was primary patency, which was defined as free from peak systolic velocity ratio (PSVR) >2.5 assessed by duplex ultrasound. Predictors for loss of patency were evaluated using Cox proportional hazards regression analysis. RESULTS: Overall 12 primary patency were 80.0±1.8%. After the multivariate analysis, reduced stroke volume evaluated by echocardiography (hazard ratio [HR]=0.99, 95% confidence interval [CI]=0.97-0.99, p=0.03), chronic heart failure (HR=1.76, 95% CI=1.05-2.97, p=0.03), and a smaller distal reference vessel diameter (HR=0.73, 95% CI=0.55-0.97, p=0.03) were significantly associated with loss of 12-month primary patency, whereas lesion length (HR=1.01, 95% CI=0.99-1.03, p=0.33) and presence of chronic total occlusion (CTO; HR=0.92, 95% CI=0.61-1.40, p=0.70) were not statistically significant. CONCLUSION: The current study revealed that cardiac function represented by reduced stroke volume and presence of chronic heart failure as well as a smaller distal reference vessel diameter were significantly associated with loss of 12-month primary patency in patients with peripheral artery disease (PAD) presenting FP lesions endovascularly treated with new-generation devices.

Clinical Impact of the Size of Drug-Coated Balloon Therapy on Restenosis Rate in Femoropopliteal Lesions.

PURPOSE: Although the size of drug-coated balloons (DCBs) is determined according to the vessel diameter during femoropopliteal (FP)-endovascular therapy (EVT), the measurements of the vessel diameter vary among modalities and its definitions. The aim of this study was to reveal whether the DCB size fitting (1) angiographically-measured lumen diameter (Angio-lumen size), (2) intravascular ultrasound (IVUS)-measured lumen diameter (IVUS-lumen size), or (3) IVUS-measured external elastic membrane (EEM) diameter (IVUS-EEM size) would be beneficial in restenosis occurrence. MATERIALS AND METHODS: This retrospective, single-center study included 231 de novo FP lesions in 165 patients with peripheral artery disease treated with IN.PACT Admiral DCB under IVUS evaluation. The reference vessel diameter was evaluated as the lumen or EEM diameter at the healthy site distal to the lesion. We retrospectively determined whether the DCB size was close to (ie, equal to or different by <0.5 mm from) Angio-lumen size, IVUS-lumen size, and IVUS-EEM size. The association of the size of DCB with restenosis risk was investigated. RESULTS: The mean lesion length was 13 ± 9 cm and the prevalence of chronic total occlusion was 18%. During a mean follow-up period of 17 ± 9 months, restenosis occurred in 26% of lesions. Lesions treated with a DCB of IVUS-EEM size had a lower 2 year restenosis rate than those treated with a DCB over/under IVUS-EEM size (19.7 ± 5.7% vs 34.5 ± 4.7%, p=0.02 by the log-rank test), while the restenosis rate was not significantly different between DCBs of Angio-lumen size or IVUS-lumen size and those over/under the size (both p>0.05). The multivariate Cox regression analysis revealed that DCBs of IVUS-EEM size were independently associated with a reduced risk of restenosis (adjusted hazard ratio 0.50; 95% confidence interval 0.27-0.95; p=0.03). CONCLUSION: The DCBs of IVUS-EEM size, but not of Angio-lumen size or IVUS-lumen size, were associated with a reduced risk of restenosis after FP-EVT. Determining the DCB size according to IVUS-evaluated EEM diameter would be potentially beneficial in restenosis occurrence.

Factors Associated With Early and Late Restenosis Following Drug-Coated Balloon Treatment for Patients With Femoropopliteal Lesions.

PURPOSE: Clinical trials have demonstrated the superiority of drug-coated balloon (DCB) to noncoated balloon angioplasty for the treatment of femoropopliteal (FP) lesions. In those trials, the difference of primary patency between DCB and noncoated angioplasty widens especially after 6 months, speculating that the antirestenosis effect of paclitaxel is manifested after 6 months. Factors associated with restenosis after 6 months differ from those associated with restenosis within 6 months. This study aimed to elucidate the prognostic factors associated with early (within 6 months) and late (after 6 months) restenosis following DCB treatment in real-world FP practice. MATERIALS AND METHODS: This multicenter, retrospective study analyzed 486 FP lesions (mean lesion length, 11.9±10.1 cm; chronic total occlusion, 21.0%) in 423 patients (diabetes mellitus, 59.3%; hemodialysis, 37.1%; chronic limb-threatening ischemia, 41.6%) who underwent successful DCB treatment between January 2018 and December 2019. The outcome measure was restenosis which is defined as a peak systolic velocity ratio >2.4 based on duplex ultrasound findings. Early and late restenosis were classified by the cutoff period of 6 months after the procedure. The associations of baseline and procedural characteristics with early and late restenosis were explored using Cox proportional hazards regression analysis. RESULTS: The mean follow-up period was 25.3±12.1 months. The 6, 12, 18, and 24 month cumulative incidences of restenosis were 7.4%±2.4%, 20.9%±3.9%, 29.9%±4.5%, and 38.4%±5.1%, respectively. During the follow-up period, early and late restenosis was evident in a total of 31 lesions and 138 lesions, respectively. Multivariate analysis revealed that chronic total occlusion (hazard ratio [HR], 2.29; 95% confidence interval [CI], 1.07-4.92; p=0.033) and superficial femoral artery ostial lesion (HR, 2.73; 95% CI, 1.28-5.80; p=0.009) were significantly associated with early restenosis. On the other hand, calcification circumference over 270° (HR, 1.67; 95% CI, 1.17-2.37; p=0.004), distal external elastic membrane diameter under 5 mm assessed by intravascular ultrasound (HR, 1.90; 95% CI, 1.29-2.79; p=0.001), and involving popliteal arterial lesion (HR, 1.54; 95% CI, 1.08-2.21; p=0.017) were significantly associated with late restenosis. CONCLUSION: The prognostic factors associated with late restenosis differed from those associated with early restenosis in the real-world FP-DCB practice. CLINICAL IMPACT: The current multicenter, retrospective study revealed that factors associated with early restenosis differed from those with late restenosis in the real-world FP-DCB practice. CTO and SFA ostial lesion were associated with early restenosis, while severe calcification, smaller vessel, and involving popliteal arterial lesions were associated with late restenosis.Early restenosis indicates "balloon failure" and would potentially result from recoil, which primary stent implantation might be required. On the other hand, late restenosis after 6 months would be attributed to "DCB failure", with inadequate drug uptake into the arterial wall, which might be minimized by the use of atherectomy devices.

Comparing Predictors Influencing Restenosis Following High-Dose Drug-Coated Balloon Angioplasty and Fluoropolymer-Based Drug-Eluting Stenting in Femoropopliteal Artery Lesions.

PURPOSE: Despite widespread use of anti-restenosis devices, drug-coated balloons (DCBs) and drug-eluting stents (DESs), their appropriate use for femoropopliteal (FP) lesions has not been well investigated and the risk factors for restenosis have not been compared. To investigate risk factors associated with restenosis after endovascular therapy using DCB and DES for contemporary FP lesions. MATERIALS AND METHODS: This single-center, retrospective, observational study evaluated 378 FP lesions in 273 patients treated with DCB (278 lesions in 193 patients) or DES (120 lesions in 106 patients). The DCB used was high-dose DCB (IN.PACT, Admiral. Medtronic, Inc.) and DES was fluoropolymer-based DES (ELUVIA, Boston Scientific). Vessel preparation failure was defined as a residual stenosis of ≥50% and a dissection grade of D or greater on pre-dilatation angiography. The outcome measure was restenosis, and factors associated with restenosis in the DCB and DES groups were assessed using a Cox proportional hazards model. RESULTS: The 2-year restenosis rate was not significantly different between the DCB and DES groups (29%±4% vs. 24%±5%, p=0.42). Interaction analysis demonstrated that popliteal lesions and plaque burden of ≥50% were restenosis-related factors for DES but not for DCB, whereas vessel preparation failure was a factor for DCB but not for DES (p<0.05). Vessel diameter of <6 mm and nodular calcification were risk factors in both groups (p<0.05). CONCLUSION: In contemporary FP lesions, smaller vessels and nodular calcification were shared restenosis-related factors for high-dose DCB and fluoropolymer-based DES. Popliteal lesions and plaque burden of ≥50% were restenosis-related factors for fluoropolymer-based DES and vessel preparation failure for high-dose DCB. CLINICAL IMPACT: Shared and differential restenosis-related factors after endovascular therapy using high-dose drug-coated balloons (DCBs) and fluoropolymer-based drug-eluting stents (DESs) in contemporary femoropopliteal (FP) lesions are unclear. This single-center retrospective study included 378 FP lesions in 273 patients with lower-extremity arterial disease (high-dose DCB, 278 lesions in 193 patients; fluoropolymer-based DES, 120 lesions in 106 patients). Smaller vessels and calcified nodules were shared restenosis-related factors for both high-dose DCB and fluoropolymer-based DES, whereas popliteal lesions and plaque burden of ≥50% were restenosis-related factors for fluoropolymer-based DES and vessel preparation failure for high-dose DCB.

Factors in Sufficient Endovascular Vessel Preparation for Severely Calcified Femoropopliteal Lesions.

BACKGROUND: Vessel preparation for endovascular treatment (EVT) is important but because the contributory factors for favorable outcomes are not yet known, we conducted the present study to elucidate the factors associated with sufficient vessel preparation for severely calcified femoropopliteal (FP) lesions.Methods and Results: This was a single-center retrospective observational study of 97 patients (mean age, 75±8 years, 76% male) with 106 de novo severely calcified FP lesions who underwent EVT under intravascular ultrasound (IVUS) evaluation. The lesion definition was 360° of superficial calcification on IVUS. The primary outcome measure was sufficient vessel preparation, which was defined as successful cracking of severely calcified lesions evaluated by IVUS after predilation. The mean lesion length was 200±103 mm, and chronic total occlusion was present in 38% of patients. According to the greater difference between the preballoon size and the lumen diameter of the severely calcified lesion, the frequency of sufficient vessel preparation increased (odds ratio, 4.68; 95% confidence interval, 2.09-10.49; P<0.01). Balloon type (noncompliant, P=0.80; scoring: P=0.25) and pressure (P=0.27) were non-contributory. CONCLUSIONS: The difference between the lumen diameter at the severely calcified FP lesion site and the preballoon dilatation diameter was the sole factor contributing to sufficient vessel preparation.

Angioscopic Evaluation of Vascular Response After Fluoropolymer-Based Drug-Eluting Stent Implantation for Femoropopliteal Artery Lesions.

BACKGROUND: Although favorable clinical outcomes have been demonstrated for fluoropolymer-based paclitaxel-eluting stents (FP-DES) in the treatment of femoropopliteal lesions, the vascular response after implantation has not been systematically studied through intravascular imaging.Methods and Results: We angioscopically compared FP-DES: 24 in the early phase (mean [±SD] 3±1 months), 26 in the middle phase (12±3 months), and 20 in the late phase (≥18 months) after implantation. The dominant neointimal coverage grade, heterogeneity of neointimal coverage grade, and thrombus adhesion in the stent segment were evaluated. Neointimal coverage was graded as follows: Grade 0, stent struts exposed; Grade 1, struts bulging into the lumen, although covered; Grade 2, struts embedded in the neointima, but visible; Grade 3, struts fully embedded and invisible. Dominant neointimal coverage and heterogeneity grades were significantly higher in the middle and late phases than in the early phase (all P<0.05), but did not differ significantly between the middle and late phases. The incidence of thrombus adhesion was recorded for all stents in each of the 3 different phases. CONCLUSIONS: The middle and late phases after FP-DES implantation were associated with significantly higher dominant neointimal coverage and heterogeneity grades than the early phase. However, thrombus adhesion was observed in all phases after FP-DES implantation. Arterial healing may not be completed even in the late phase after FP-DES implantation.

Impact of intravascular ultrasound parameters and platelet reactivity on primary patency after drug-coated balloon angioplasty for femoropopliteal artery disease.

Although the superiority of DCBs to uncoated balloon angioplasty for the treatment of femoropopliteal (FP) lesions has been demonstrated, the association of clinical factors, including anatomical features evaluated by intravascular ultrasound (IVUS) and platelet reactivity, with the loss of patency has not been systematically studied. The current prospective, observational study enrolled 160 consecutive patients (male 67.5%, mean age 74.7 ± 9.7 years) with 213 FP lesions treated with DCBs under IVUS evaluation. The platelet reactivity was measured in P2Y12 reaction units for all of the patients at the DCB treatment. The primary end point was primary patency at 12 months, while the secondary end points were freedom from target lesion revascularization (TLR), all-cause death, major target limb amputation and bleeding events at 12 months. Mean lesion length was 11.9 ± 9.4 cm and 34 (16.0%) were chronic total occlusions (CTOs). Thirty-four (16.0%) were severely calcified lesions. Primary patency by Kaplan-Meier estimate was 79.2% at 12 months, while the 12-month freedom from TLR, all-cause death and bleeding events were observed in 89.1%, 93.4% and 97.4%, respectively. There were no major target limb amputations through 12 months. Multivariate analysis showed that subintimal angioplasty for CTO lesions was a sole risk factor for loss of 12-month primary patency, while other IVUS parameters and platelet reactivity were not.

Impact of left atrial low-voltage areas during initial ablation procedures on very late recurrence of atrial fibrillation.

BACKGROUND: Very late recurrence of atrial fibrillation (VLRAF) occurring >1 year after catheter ablation may influence long-term follow-up strategies, including oral anticoagulant therapy. However, little is known about the predictors of this condition. Given that the prevalence of left atrial low-voltage areas (LVAs) is strongly associated with the recurrence of atrial tachyarrhythmias following catheter ablation, we hypothesized that VLRAF might occur more frequently in patients with LVAs at the time of initial ablation. The purpose of this study was to investigate the impact of LVAs on VLRAF. METHODS: This study included 1001 consecutive patients undergoing initial ablation procedures for AF. LVAs were defined as regions with bipolar peak-to-peak voltages of <0.50 mV on the voltage map obtained during sinus rhythm after pulmonary vein isolation. During a 1-year follow-up period, 248 patients had a late recurrence of AF (LRAF), defined as recurrence within 3-12 months after ablation. The occurrence of VLRAF was examined in 711 patients without LRAF who were followed for more than 1 year. RESULTS: A total of 711 patients who did not develop AF recurrence within 1 year and for whom clinical data were available after 1 year were analyzed. During a median follow-up of 25 (19, 37) months, VLRAF more than 1 year after the initial ablation was detected in 123 patients. On multivariate analysis, independent predictors of VLRAF were the existence of LVAs, female, left atrial diameter and early recurrence of AF. A Kaplan-Meier analysis showed that the AF-free survival rate was significantly lower in patients with LVAs than in those without LVAs within 1 year and on more than 1-year follow-up (p < .001). An additional Kaplan-Meier analysis of the incidence of VLRAF in propensity score-matched patients with and without LVAs showed that VLRAF occurred significantly more frequently in patients with LVAs (p = .003). CONCLUSIONS: LVAs during the initial AF ablation procedures have an impact on VLRAF occurrence.

Incidence of Acute Thrombotic Occlusion and Its Predictors After Contemporary Femoropopliteal Endovascular Therapy in Patients With Peripheral Artery Disease.

PURPOSE: This study investigated the incidence of acute thrombotic occlusion (ATO) and its predictors after contemporary femoropopliteal (FP) endovascular therapy (EVT) for peripheral artery disease. MATERIALS AND METHODS: We retrospectively examined 763 limbs (chronic limb-threatening ischemia [CLTI]: 44%, involving popliteal lesion: 44%) in 644 patients (mean age: 75±9 years, male: 71%, hemodialysis: 34%) who successfully underwent EVT with contemporary FP devices (drug-coated stent: n=220, stent graft: n=158, drug-eluting stent: n=150, drug-coated balloon [DCB]: n=235) from June 2012 to July 2020. The outcome measure was ATO defined as acute onset of claudication and/or signs of CLTI in combination with angiographic evidence of occlusive thrombus formation within the treated segment. Cox proportional hazards regression models were used to identify baseline characteristics associated with the incidence of ATO after EVT treated with scaffold. To determine the impact of ATO occurrence and creatine phosphokinase (CPK) elevation on the subsequent composite outcome of mortality or major amputation, we developed the Cox model in which the trichotomous variable (free from ATO, ATO without CPK elevation, and ATO with CPK elevation) was a time-dependent covariate. RESULTS: The 24-month incidence of ATO in the overall population was 4.3%±0.8% (DCB: 1.0%±0.7% vs scaffold: 5.8%±1.1%, p<0.01). Hemodialysis (hazard ratio [HR]: 2.63, p=0.02) and involving popliteal lesion (HR: 8.22, p<0.01) were independently associated with an increased risk of ATO in patients treated with scaffold. Both ATO without CPK elevation and ATO with CPK elevation were significantly associated with a composite outcome of mortality or major amputation comparing free from ATO, with an HR of 2.39 and 9.87, respectively (p=0.02 and p<0.01). CONCLUSION: We found a substantial incidence of ATO after contemporary FP-EVT, particularly with scaffold. Hemodialysis and involving popliteal lesion were significantly associated with ATO risk in patients treated with scaffold. The occurrence of ATO, particularly with CPK elevation, was associated with an increased risk of a subsequent composite outcome of mortality or major amputation. The scaffold was safely used in patients without those risk factors of ATO, but a non-scaffolding strategy should be considered for patients with more risk factors. CLINICAL IMPACT: The scaffold was safely used in patients without hemodialysis and involving popliteal lesion, but a non-scaffolding strategy should be considered for patients with those risk factors. The occurrence of ATO, particulary with CPK elevation, was of high risk of mortality or amputation.

Low-Voltage-Area Ablation in Paroxysmal Atrial Fibrillation　- Extended Follow-up Results of the VOLCANO Trial.

BACKGROUND: The randomized controlled VOLCANO trial demonstrated comparable 1-year rhythm outcomes between patients with and without ablation targeting low-voltage areas (LVAs) in addition to pulmonary vein isolation among paroxysmal atrial fibrillation (PAF) patients with LVAsMethods and Results:An extended-follow-up study of 402 patients enrolled in the VOLCANO trial with PAF, divided into 4 groups based on the results of voltage mapping: group A, no LVA (n=336); group B, LVA ablation (n=30); group C, LVA without ablation (n=32); and group D, incomplete voltage map (n=4). At 25 (23, 31) months after the initial ablation, AF/atrial tachycardia (AT) recurrence rates were 19% in group A, 57% in group B, 59% in group C, and 100% in group D. Recurrence rates were higher in patients with LVAs than in those without (group A vs. B+C, P<0.0001), and were comparable between those with and without LVA ablation (group B vs. C, P=0.83). Among patients who underwent repeat ablation, ATs were more frequently observed in patients with LVAs (Group B+C, 50% vs. A, 14%, P<0.0001). In addition, LVA ablation increased the incidence of AT development (group B, 71% vs. C, 32%, P<0.0001). CONCLUSIONS: Patients with LVAs demonstrated poor long-term rhythm outcomes irrespective of LVA ablation. ATs were frequently observed in patients with LVAs, and LVA ablation might exacerbate the occurrence of iatrogenic ATs.

Left Atrial Localized Low-Voltage Areas Indicate Whole Left Atrial Electrophysiological Degeneration in Atrial Fibrillation Patients.

BACKGROUND: The efficacy of ablation targeting low-voltage areas (LVAs) is controversial, although LVA presence is well known to be associated with atrial fibrillation (AF) recurrence after ablation. AF substrate may not localize within LVAs.Methods and Results:This observational study enrolled 405 consecutive patients who underwent an initial AF ablation procedure. The left atrial (LA) voltage map was obtained after pulmonary vein isolation. LVAs were defined as areas with voltage <0.5 mV. To estimate whole LA electrophysiological degeneration, mean regional voltage at each of the 6 regions and LA total conduction velocity were measured. LVAs existed in 143 of 405 (35.3%) patients. Patients with LVAs demonstrated lower mean regional voltages throughout all 6 regions compared to those without LVAs (1.3 [1.8, 0.8] vs. 0.6 [1.0, 0.2] mV for the anterior wall, P<0.001). In contrast, LA conduction velocity was lower in patients with LVAs than in those without (0.89 [1.01, 0.74] vs. 0.93 [1.03, 0.87] m/s, P<0.001). Multivariate analysis revealed that low LA total conduction velocity and a higher number of regions with mean voltage reduction were independently associated with AF recurrence, although LVA presence was not. CONCLUSIONS: Patients with localized LA LVAs were characterized by whole LA electrophysiological degeneration as assessed by mean regional voltage and conduction velocity. In addition, whole LA electrophysiological degeneration parameters were well associated with AF recurrence.

Comparison of 1-Month and 12-Month Vessel Responses Between the Polymer-Free Biolimus A9-Coated Stent and the Durable Polymer Everolimus-Eluting Stent.

BACKGROUND: A polymer-free biolimus A9-coated stent (PF-BCS) may achieve better arterial healing than a durable polymer drug-eluting stent owing to its polymer-free feature.Methods and Results: This multicenter, prospective, observational study enrolled 105 patients (132 lesions) who underwent PF-BCS (51 patients, 71 lesions) or durable polymer everolimus-eluting stent (DP-EES, 54 patients, 61 lesions) implantation. Serial coronary angioscopy (CAS) and optical coherence tomography (OCT) examinations were performed at 1 and 12 months, and the serial vessel responses were compared between PF-BCS and DP-EES. The primary outcome measure was the incidence of subclinical intrastent thrombus on CAS. The secondary outcome measures were: adequate strut coverage (≥40 µm) on OCT and maximum yellow color grade on CAS. The incidence of thrombus was high at 1 month (100% vs. 93%, P=0.091), but decreased at 12 months (18% vs. 25%, P=0.56), without a significant difference between PF-BCS and DP-EES. The adequate strut coverage rate was significantly higher (84±14% vs. 69±22%, P<0.001) and yellow color was significantly less intense (P=0.012) at 12 months in PF-BCS than in DP-EES; however, they were not significantly different at 1 month (adequate strut coverage: 47±21% vs. 50±17%, P=0.40; yellow color: P=0.99). CONCLUSIONS: Although the thrombogenicity of PF-BCS was similar to that of DP-EES, the adequate coverage and plaque stabilization rates of PF-BCS were superior to those of DP-EES at 12 months.

Long-Term Outcomes in Elderly Patients After Deferral of Coronary Revascularization Guided by Fractional Flow Reserve.

BACKGROUND: Little evidence is available regarding the long-term outcome in elderly patients after deferral of revascularization based on fractional flow reserve (FFR).Methods and Results: From the J-CONFIRM registry (long-term outcomes of Japanese patients with deferral of coronary intervention based on fractional flow reserve in multicenter registry), 1,262 patients were divided into 2 groups according to age: elderly and younger patients (aged ≥75 or <75 years, respectively). The primary endpoint was the cumulative 5-year incidence of target vessel failure (TVF), defined as a composite of cardiac death, target vessel-related myocardial infarction (TVMI), and clinically driven target vessel revascularization (CDTVR). Cumulative 5-year incidence of TVF was not significantly different between elderly and younger patients (14.3% vs. 10.8%, P=0.12). Cardiac death occurred more frequently in elderly patients than younger patients (4.4% vs. 0.8%, P<0.001), whereas TVMI and CDTVR did not differ between groups (1.3% vs. 0.9%, P=0.80; 10.7% vs. 10.1%, P=0.80, respectively). FFR values in lesions with diameter stenosis <50% were significantly higher in elderly patients than in younger patients (0.88±0.07 vs. 0.85±0.07, P=0.01), whereas this relationship was not observed in those with diameter stenosis ≥50%. CONCLUSIONS: Elderly patients had no excess risk of ischemic events related to the deferred coronary lesions by FFR, although FFR values in mild coronary artery stenosis were modestly different between elderly and younger patients.