Association between defibrillation-to-adrenaline interval and short-term outcomes in patients with out-of-hospital cardiac arrest and an initial shockable rhythm.

Aim: The optimal timing of adrenaline administration after defibrillation in patients with out-of-hospital cardiac arrest (OHCA) and an initial shockable rhythm is unknown. We investigated the association between the defibrillation-to-adrenaline interval and clinical outcomes. Methods: Between 2011 and 2020, we enrolled 1,259,960 patients with OHCA into a nationwide prospective population-based registry in Japan. After applying exclusion criteria, 20,905 patients with an initial shockable rhythm documented at emergency medical services (EMS) arrival who received adrenaline after defibrillation were eligible for this study. Multivariable logistic regression analysis was used to predict favourable short-term outcomes: prehospital return of spontaneous circulation (ROSC), 30-day survival, or a favourable neurological outcome (Cerebral Performance Category 1 or 2) at 30 days. Patients were categorised into 2-minute defibrillation-to-adrenaline intervals up to 18 min, or more than 18 min. Results: At 30 days, 1,618 patients (8%) had a favourable neurological outcome. The defibrillation-to-adrenaline interval in these patients was significantly shorter than in patients with an unfavourable neurological outcome [8 (5-12) vs 11 (7-16) minutes; P < 0.001]. The proportion of patients with prehospital ROSC, 30-day survival, or a favourable neurological outcome at 30 days decreased as the defibrillation-to-adrenaline interval increased (P < 0.001 for trend). Multivariable analysis revealed that a defibrillation-to-adrenaline interval of > 6 min was an independent predictor of worse prehospital ROSC, 30-day survival, or neurological outcome at 30 days when compared with an interval of 4-6 min. Conclusion: A longer defibrillation-to-adrenaline interval was significantly associated with worse short-term outcomes in patients with OHCA and an initial shockable rhythm.

Role of Vascular Function in the Prognosis of Heart Failure Patients.

Background: Blood vessels have the Windkessel effect and are involved in blood circulation. The breakdown of this mechanism is also involved in the pathogenesis of heart failure (HF); however, the relationship between vascular dysfunction and HF prognosis is not fully understood. Methods: We evaluated 214 patients hospitalized for HF at our institution who underwent a cardio-ankle vascular index (CAVI), which evaluates vascular function, between January 2012 and July 2018. To investigate factors (including CAVI) associated with major adverse cardiac events (MACE) during 1 year after patients with HF were discharged, we evaluated clinical profiles, blood tests, chest X-P, 12-lead electrocardiography, and transthoracic echocardiographic findings. MACE was defined as cardiovascular death or readmission for HF. Results: The severity of HF between the MACE and non-MACE was not significantly different. Previous HF and chronic kidney disease were significantly more common in the MACE group. CAVI and % mean atrial pressure in the MACE group were statistically higher than those in the non-MACE group. The cardiac shadow as shown by chest X-P and left ventricular size in the MACE group were significantly bigger, and HF preserved ejection fraction (EF) (EF > 50%) was significantly more common in the MACE group. In multivariate analysis, CAVI was an independent predictive factor for the occurrence of MACE (model 1; hazard ratio (HR): 1.33, 95% confidence interval (CI): 1.05-1.68, p = 0.018; model 2; HR: 1.31, 95% CI: 1.07-1.60, p = 0.009). Conclusions: Because high CAVI is associated with poor prognosis of HF, these patients require more careful treatment.

Impact of post-procedural peripheral fractional flow reserve after drug-coated balloon angioplasty in femoropopliteal lesions.

PURPOSE: The aim of this study was to determine if postprocedural peripheral fractional flow reserve (pFFR) is associated with patency one year after drug-coated balloon (DCB) angioplasty for femoropopliteal (FP) lesions. MATERIALS AND METHODS: Forty-five consecutive patients having 49 de novo FP lesions were enrolled in this prospective, observational study conducted from April 2022 to Aug 2023. The pFFR was measured under hyperemic conditions after the administration of 30 mg of papaverine. The relationship between pFFR and restenosis 12 months after the procedure was determined using receiver operating characteristic (ROC) curve analysis. RESULTS: The one-year follow-up was completed for 47 lesions (95.9 %). Restenosis was detected in 7 lesions (14.9 %). Postprocedural pFFR was significantly higher in the nonrestenosis group compared with the pFFR in the stenosis group (0.95 ± 0.054 vs. 0.88 ± 0.090, p = 0.010). The optimal pFFR cutoff value for predicting restenosis was 0.92 (sensitivity, 0.824; specificity, 0.600). The area under the curve for pFFR was numerically higher than the area under the curve for minimum lumen area (0.73 vs. 0.64, p = 0.22). Rates of freedom from restenosis at one year were significantly higher in the pFFR >0.92 group compared with the pFFR ≤0.92 group (p = 0.0042). CONCLUSION: Postprocedural pFFR was associated with patency at one year after DCB angioplasty for FP lesions.

Impact of High-Voltage Device Implantation in Elderly Japanese Patients With Heart Failure as Primary Prevention　- Post Hoc Analysis of HINODE.

BACKGROUND: Despite an increased incidence of chronic heart failure (HF) and sudden cardiac death (SCD), the use of implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy (CRT) is much lower in Japan than in Western countries. The HF Indication and SCD Prevention Trial Japan (HINODE) prospectively assessed the mortality rate, appropriately treated ventricular arrhythmias (VA), and HF in Japanese patients with a higher risk of HF.Methods and Results: HINODE consisted of ICD, CRT-defibrillator (CRT-D), pacing, and non-device treatment cohorts. This subanalysis evaluated the impact of the implantation of high-voltage devices (HVD; ICD and CRT-D) in 171 Japanese patients. We compared all-cause mortality, VA, and HF events between elderly (age >70 years at study enrollment) and non-elderly HVD recipients. The estimated survival rate through 24 months in the HVD cohort was 85.8% (97.5% lower control limit 77.6%). The risk of all-cause mortality was increased for the elderly vs. non-elderly (hazard ratio [HR] 2.82; 95% confidence interval [CI] 1.01-7.91; P=0.039), but did not differ after excluding ICD patients with CRT-D indication (HR 2.32; 95% CI 0.79-6.78; P=0.11). There were no differences in VA and HF event-free rates between elderly and non-elderly HVD recipients (P=0.73 and P=0.55, respectively). CONCLUSIONS: Although elderly patients may have a higher risk of mortality in general, the benefit of HVD therapy in this group is comparable to that in non-elderly patients.

Gastrointestinal bleeding in elderly patients with atrial fibrillation: prespecified All Nippon Atrial Fibrillation in the Elderly (ANAFIE) Registry subgroup analysis.

Gastrointestinal (GI) bleeding control is critical in elderly patients with atrial fibrillation (AF) receiving oral anticoagulants (OAC). This subgroup analysis aimed to clarify the actual state and significance of GI bleeding in elderly non-valvular AF (NVAF) patients. We evaluated the incidence and risk factors of GI bleeding during the 2-year follow-up and examined the GI bleeding impact on mortality. Of the 32,275 patients in the ANAFIE Registry, 1139 patients (3.5%) experienced GI bleeding (incidence rate, 1.92 events per 100 person-years; mean follow-up, 1.88 years); 339 upper and 760 lower GI bleeding events occurred. GI bleeding risk factors included age ≥ 85 years, body mass index ≥ 25.0 kg/m2, prior major bleeding, hyperuricaemia, heart failure, P-glycoprotein inhibitor use, GI disease, and polypharmacy (≥ 5 drugs). No significant differences in GI bleeding risk were found between direct OAC (DOAC) vs warfarin users (adjusted hazard ratios [95% confidence interval], 1.01 [0.88-1.15]). The 1-year post-GI bleeding mortality rate was numerically higher in patients with upper (19.6%) than lower GI bleeding (8.9%). In elderly Japanese NVAF patients, this large-scale study found no significant difference in GI bleeding risk between DOAC vs. warfarin users or 1-year mortality after upper or lower GI bleeding.

Electrophysiological evidence of right atrial epicardial connections in a case with recurrent common atrial flutter.

The majority of the cavotricuspid isthmus (CTI) region consists of discretely arranged muscle bundles separated by connective tissue. Heterogeneity in the anatomic arrangement of the muscle bundles results in differences in the endocardial and epicardial activation patterns. We present a case of recurrent atrial flutter (AFL) despite the presence of a complete endocardial CTI block. We found epicardial-endocardial breakthrough (EEB) sites on the right atrial high septum. In addition, the epicardial excitation confirmed by endocardial activation mapping was detected as far-field potentials. Radiofrequency ablation was performed at the EEB site. No AFL has recurred for 12 months after the present procedure.

Impact of Atrial Fibrillation Triggers on Long-Term Outcomes of a Second Catheter Ablation of Nonparoxysmal Atrial Fibrillation.

Background: Catheter ablation (CA) of atrial fibrillation (AF) triggers, including non-pulmonary vein (PV) foci, contributes to improved procedural outcomes. However, the clinical significance of an AF trigger ablation during second CA procedures for nonparoxysmal AF is unknown. Methods and Results: We enrolled 94 patients with nonparoxysmal AF undergoing a second CA. Intracardiac cardioversion during AF using high-dose isoproterenol was performed to determine the presence or absence of AF triggers. PV re-isolations were performed if PV potentials recurred, and if AF triggers appeared from any non-PV sites, additional ablation was added to those sites. We investigated the incidence of atrial arrhythmia recurrence (AAR) >3 months post-CA. Of the 94 enrolled patients, AF triggers were identified in 65 (69.1%), and of those with AF triggers, successful elimination of the triggers was achieved in 47 patients (72.3%). Multivariate analysis revealed that no observed AF triggers were a significant predictor of AAR (hazard ratio [HR] 1.97, 95% confidence interval [CI] 1.21-3.46, P=0.019). In a subanalysis of the patients with AF triggers, multivariate analysis showed that unsuccessful trigger ablation was significantly associated with AAR (HR 5.84, 95% CI 2.79-12.22, P<0.01). Conclusions: Having no observed AF triggers during a second CA session significantly increased the risk of AAR, as did unsuccessful CA of AF triggers.

Expert consensus document on automated diagnosis of the electrocardiogram: The task force on automated diagnosis of the electrocardiogram in Japan part 3: Inappropriate internal processing in the automatic diagnosis of electrocardiograms and its problems.

Computer diagnosis of electrocardiograms is widely used to provide useful information in clinical practice and medical checkups. However, it is common for users to be confused by the inappropriate diagnosis. We illustrate some examples of inappropriate automatic diagnoses and discuss the actual situation of inappropriate automatic processing and its problems.

Impact of Updating the Cardiopulmonary Resuscitation Guidelines on Out-of-Hospital Shockable Cardiac Arrest: A Population-Based Cohort Study in Japan.

BACKGROUND: International consensus on cardiopulmonary resuscitation (CPR) and emergency cardiovascular care science and treatment recommendations (CoSTR) have reported updates on CPR maneuvers every 5 years since 2000. However, few national population-based studies have investigated the comprehensive effectiveness of those updates for out-of-hospital cardiac arrest due to shockable rhythms. The primary objective of the present study was to determine whether CPR based on CoSTR 2005 or 2010 was associated with improved outcomes in Japan, as compared with CPR based on Guidelines 2000. METHODS AND RESULTS: From the All-Japan Utstein Registry between 2005 and 2015, we included 73 578 adults who had shockable out-of-hospital cardiac arrest witnessed by bystanders or emergency medical service responders. The study outcomes over an 11-year period were compared between 2005 of the Guidelines 2000 era, from 2006 to 2010 of the CoSTR 2005 era, and from 2011 to 2015 of the CoSTR 2010 era. In the bystander-witnessed group, the adjusted odds ratios for favorable neurological outcomes at 30 days after out-of-hospital cardiac arrest by enrollment year increased year by year (1.19 in 2006, and 3.01 in 2015). Similar results were seen in the emergency medical service responder-witnessed group and several subgroups. CONCLUSIONS: Compared with CPR maneuvers for shockable out-of-hospital cardiac arrest recommended in the Guidelines 2000, CPR maneuver updates in CoSTR 2005 and 2010 were associated with improved neurologically intact survival year by year in Japan. Increased public awareness and greater dissemination of basic life support may be responsible for the observed improvement in outcomes. REGISTRATION: URL: https://www.umin.ac.jp/ctr/; Unique identifier: 000009918.

Coronary events in elderly patients with non-valvular atrial fibrillation: a prespecified sub-analysis of the ANAFIE registry.

Real-world data on coronary events (CE) in elderly patients with atrial fibrillation (AF) are lacking in the direct oral anticoagulant era. This prespecified sub-analysis of the ANAFIE Registry, a prospective observational study in > 30,000 Japanese patients aged ≥ 75 years with non-valvular AF (NVAF), investigated CE incidence and risk factors. The incidence and risk factors for new-onset CE (a composite of myocardial infarction [MI] and cardiac intervention for coronary heart diseases other than MI), MI, and cardiac intervention for coronary heart diseases other than MI during the 2-year follow-up were assessed. Bleeding events in CE patients were also examined. Among 32,275 patients, the incidence rate per 100 patient-years was 0.48 (95% confidence interval (CI): 0.42-0.53) for CE during the 2-year follow-up, 0.20 (0.16-0.23) for MI, and 0.29 (0.25-0.33) for cardiac intervention for coronary heart diseases other than MI; that of stroke/systemic embolism was 1.62 (1.52-1.73). Patients with CE (n = 287) likely had lower creatinine clearance (CrCL) and higher CHADS2 and HAS-BLED scores than patients without CE (n = 31,988). Significant risk factors associated with new-onset CE were male sex, systolic blood pressure of ≥ 130 mmHg, diabetes mellitus (glycated hemoglobin ≥ 6.0%), CE history, antiplatelet agent use, and CrCL < 50 mL/min. Major bleeding incidence was significantly higher in patients with new-onset CE vs without CE (odds ratio [95% CI], 3.35 [2.06-5.43]). In elderly patients with NVAF, CE incidence was lower than stroke/systemic embolism incidence. New-onset CE (vs no CE) was associated with a higher incidence of major bleeding.Trial registration: UMIN000024006.

The impact of statins treatments for plaque characteristics in stable angina pectoris patients with very low and high low-density lipoprotein cholesterol levels: an intracoronary optical coherence tomography study.

Low-density lipoprotein cholesterol (LDL-C) levels are recommended according to the patient's risk factors based on guidelines. In patients achieving low LDL-C levels, the need for statins is uncertain, and the plaque characteristics of patients not treated with statins are unclear. In addition, the difference in plaque characteristics with and without statins is unclear in similarly high LDL levels. We evaluate the impact of statins on plaque characteristics on optical coherence tomography (OCT) in patients with very low LDL-C levels and high LDL-C levels. A total of 173 stable angina pectoris patients with 173 lesions undergoing OCT before percutaneous coronary intervention were evaluated. We divided the LDL-C levels into three groups: < 70 mg/dL (n = 48), 70 mg/dL ≤ LDL-C < 100 mg/dL (n = 71), and ≥ 100 mg/dL (n = 54). Among patients with LDL-C < 70 mg/dL, patients not treated with statins showed a significantly higher C-reactive protein level (0.27 ± 0.22 mg/dL vs. 0.15 ± 0.19 mg/dL, p = 0.049), and higher incidence of thin-cap fibroatheromas (TCFAs; 44% [7/16] vs. 13% [4/32], p = 0.021) than those treated with statins. Among patients with LDL-C level ≥ 100 mg/dL, patients treated with statins showed a significantly higher prevalence of familial hypercholesterolemia (FH) (38% [6/16] vs. 5% [2/38], p = 0.004), lower incidence of TCFAs (6% [1/16] vs. 39% [15/38], p = 0.013), healed plaques (13% [2/16] vs. 47% [18/38], p = 0.015), and higher incidence of fibrous plaques (75% [12/16] vs. 42% [16/38], p = 0.027) than patients not treated with statins. While patients achieved a low LDL-C, patients not treated with statins had high plaque vulnerability and high systemic inflammation. While patients had a high LDL-C level with a high prevalence of FH, patients treated with statins had stable plaque characteristics.

Clinical outcomes and anticoagulation therapy in elderly non-valvular atrial fibrillation and heart failure patients.

AIMS: Atrial fibrillation (AF) and heart failure (HF) often coexist. Older age is strongly associated with stroke, HF, and mortality. The association between coexistence of HF and a risk of clinical outcomes and the effectiveness of anticoagulation therapy including direct oral anticoagulants (DOACs) in elderly patients with AF and HF have not been investigated. We aimed to evaluate 2 years of outcomes and to elucidate the efficacy of DOACs or warfarin in elderly AF patients in the All Nippon AF In the Elderly (ANAFIE) Registry with and without a history of HF. METHODS AND RESULTS: The ANAFIE Registry is a multicentre, prospective observational study following elderly non-valvular AF patients aged ≥75 years for 2 years. Hazard ratios (HRs) were calculated based on the presence or absence of an HF diagnosis and DOAC or warfarin use at enrolment. Among 32 275 eligible patients, 12 116 (37.5%) had been diagnosed with HF. Patients with HF had significantly higher rates of HF hospitalization or cardiovascular death (HR 1.94, P < 0.001), cardiovascular events (HR 1.59, P < 0.001), cardiovascular death (HR 1.49, P < 0.001), all-cause death (HR 1.32, P < 0.001), and net clinical outcome including stroke/systemic embolism, major bleeding, and all-cause death (HR 1.23, P < 0.001), compared with those without HF; however, HRs for stroke/systemic embolism (HR 0.96, P = 0.56) and major bleeding (HR 1.14, P = 0.13) were similar. DOAC use was associated with a low risk of stroke/systemic embolism (HR 0.86, P = 0.19 in HF; HR 0.79, P = 0.016 in non-HF; P for interaction = 0.56), major bleeding (HR 0.71, P = 0.008 in HF; HR 0.75, P = 0.016 in non-HF; P for interaction = 0.74), HF hospitalization or cardiovascular death (HR 0.81, P < 0.001 in HF; HR 0.78, P < 0.001 in non-HF; P for interaction = 0.26), cardiovascular events (HR 0.83, P < 0.001 in HF; HR 0.82, P = 0.001 in non-HF; P for interaction = 0.65), cardiovascular death (HR 0.84, P = 0.12 in HF; HR 0.75, P = 0.035 in non-HF; P for interaction = 0.18), all-cause death (HR 0.89, P = 0.082 in HF; HR 0.80, P = 0.001 in non-HF; P for interaction = 0.091), and net clinical outcome (HR 0.88, P = 0.019 in HF; HR 0.81, P < 0.001 in non-HF; P for interaction = 0.21) compared with warfarin, irrespective of the presence or absence of HF. Analysis using the propensity score matching method showed similar associations. CONCLUSIONS: Non-valvular AF patients aged ≥75 years with a history of HF had higher risks of cardiovascular events and mortality. DOACs were favourable to warfarin regardless of the coexistence of HF. These results might encourage the use of DOACs in elderly patients with non-valvular AF with or without HF.

Impact of a national initiative to provide civilian cardiopulmonary resuscitation training courses on the rates of bystander intervention by citizens and survival after out-of-hospital cardiac arrest.

BACKGROUND: The impact of a national initiative to provide cardiopulmonary resuscitation (CPR) education to the public on the rates of citizen-initiated CPR and survival following out-of-hospital cardiac arrest (OHCA) remains uncertain. METHODS: We examined 358,025 cases of citizen-witnessed OHCA with presumed cardiac origin, recorded in the Japanese nationwide registry from 2005 to 2020. We assessed the relationship between the number of individuals certified in CPR courses, citizen interventions, and neurologically favorable survival at one month. RESULTS: The cumulative number of certified citizens has linearly increased from 9,930,327 in 2005 to 34,938,322 in 2020 (incidence rate ratio for annual number = 1.03, p < 0.001), encompassing 32.3% of the Japanese population aged 15 and above. Similarly, the prevalence of citizen-initiated CPR has consistently increased from 40.6% in 2005 to 56.8% in 2020 (P for trend < 0.001). Greater citizen CPR engagement was significantly associated with better outcome in initial shockable rhythm patients [chest compression only: odds ratio (OR) 1.24; 95% confidence interval (CI) 1.02-1.51; P = 0.029; chest compression with rescue breathing: OR 1.33; 95% CI 1.08-1.62; P = 0.006; defibrillation with chest compression: OR 2.27; 95% CI 1.83-2.83; P < 0.001; defibrillation with chest compression and rescue breathing: OR 2.15; 95% CI 1.70-2.73; P < 0.001 vs. no citizen CPR]. CONCLUSIONS: The incidence of citizen-initiated CPR across Japan has consistently and proportionately increased with the rising number of individuals certified in CPR courses. Greater citizen CPR involvement has been linked to neurologically favorable survival, particularly in cases with an initial shockable rhythm.

ISE/ISHNE expert consensus statement on the ECG diagnosis of left ventricular hypertrophy: The change of the paradigm.

The ECG diagnosis of LVH is predominantly based on the QRS voltage criteria. The classical paradigm postulates that the increased left ventricular mass generates a stronger electrical field, increasing the leftward and posterior QRS forces, reflected in the augmented QRS amplitude. However, the low sensitivity of voltage criteria has been repeatedly documented. We discuss possible reasons for this shortcoming and proposal of a new paradigm. The theoretical background for voltage measured at the body surface is defined by the solid angle theorem, which relates the measured voltage to spatial and non-spatial determinants. The spatial determinants are represented by the extent of the activation front and the distance of the recording electrodes. The non-spatial determinants comprise electrical characteristics of the myocardium, which are comparatively neglected in the interpretation of the QRS patterns. Various clinical conditions are associated with LVH. These conditions produce considerable diversity of electrical properties alterations thereby modifying the resultant QRS patterns. The spectrum of QRS patterns observed in LVH patients is quite broad, including also left axis deviation, left anterior fascicular block, incomplete and complete left bundle branch blocks, Q waves, and fragmented QRS. Importantly, the QRS complex can be within normal limits. The new paradigm stresses the electrophysiological background in interpreting QRS changes, i.e., the effect of the non-spatial determinants. This postulates that the role of ECG is not to estimate LV size in LVH, but to understand and decode the underlying electrical processes, which are crucial in relation to cardiovascular risk assessment.

Impact of osteoporotic risk in women undergoing transcatheter aortic valve replacement.

Low body weight and advanced age are reported to be among the best predictors of osteoporosis, and osteoporosis self-assessment tool (OST) values are calculated using a simple formula to identify postmenopausal women at increased risk of osteoporosis. In our recent study, we demonstrated an association between fractures and poor outcomes in postmenopausal women following transcatheter aortic valve replacement (TAVR). In this study, we aimed to investigate the osteoporotic risk in women with severe aortic stenosis and determined whether an OST could predict all-cause mortality following TAVR. The study population comprised 619 women who underwent TAVR. Compared to a quarter of patients with diagnosis of osteoporosis, 92.4% of participants were at high risk of osteoporosis based on OST criteria. When divided into tertiles based on OST values, patients in tertile 1 (lowest OST) displayed increased frailty, a higher incidence of multiple fractures, and greater Society of Thoracic Surgeons scores. Estimated all-cause mortality survival rates 3 years post-TAVR were 84.2 ± 3.0%, 89.5 ± 2.6%, and 96.9 ± 1.7% for OST tertiles 1, 2, and 3, respectively (p = 0.001). Multivariate analysis showed that the OST tertile 3 was associated with decreased risk of all-cause mortality compared with OST tertile 1 as the referent. Notably, a history of osteoporosis was not associated with all-cause mortality. Patients with high osteoporotic risk are highly prevalent among those with aortic stenosis according to the OST criteria. OST value is a useful marker for predicting all-cause mortality in patients undergoing TAVR.

Left Atrial Appendage Closure with the Watchman FLX System in a Patient with Hypertrophic Cardiomyopathy on Dialysis for End-stage Renal Failure.

Patients with hypertrophic cardiomyopathy (HCM) often have atrial fibrillation, and empiric anticoagulation is recommended in these patients, regardless of other risk factors. However, anticoagulation is not recommended for patients who require hemodialysis (HD) because of the high bleeding risk. We herein report a case of left atrial appendage closure (LAAC) using the Watchman FLX system for a dilated phase HCM patient complicated by persistent atrial fibrillation and requiring HD. LAAC with the Watchman FLX system may be an alternative to antithrombotic medications in patients with dilated HCM complicated by atrial fibrillation and requiring HD.

Correlation between physiological assessment and imaging findings during drug-coated balloon treatment for femoropopliteal diseases.

BACKGROUND: This prospective cross-sectional study evaluated the correlation between physiological assessment (PA) and minimum lumen area (MLA) by intravascular ultrasound (IVUS) during drug-coated balloon (DCB) treatment for femoropopliteal (FP) diseases. METHODS: A total of 51 limbs of 44 patients undergoing endovascular treatment with DCB for de novo FP disease were examined from April 2022 to February 2023. PA was conducted at baseline, after balloon dilatation, and after DCB treatment. PA was measured before (pressure ratio; PR) and after vasodilation (peripheral flow fractional flow reserve; pFFR) with the administration of 30 mg papaverine through a guiding catheter. The correlation of PA with percent diameter stenosis (%DS) and MLA was examined, and factors correlated with higher pFFR after balloon dilatation were evaluated in a multivariate analysis. RESULTS: At baseline, there were correlations between pressure ratio (PR) and %DS (coefficients: 0.641 [p < 0.001]) and between pFFR and %DS (0.666 [p < 0.001]). After balloon dilatation, there was no correlation between PR and %DS (coefficients: 0.33 [p = 0.27]) or between pFFR and %DS (0.41 [p = 0.71]). At baseline, PR and MLA were correlated (coefficients: 0.757 [p < 0.001]) as were pFFR and MLA (0.762 [p < 0.001]). After balloon dilatation, PR and MLA were correlated (coefficients: 0.524 [p < 0.001]) as were pFFR and MLA (0.601 [p < 0.001]). Balloon/EEM ratio, calcification >270°, and chronic total occlusion were associated with pFFR after balloon dilatation. CONCLUSION: After balloon dilatation, PA was correlated with MLA by IVUS but not with %DS based on angiography.