Two-year clinical outcomes of drug-coated balloon angioplasty and angiographic predictors of restenosis among patients with de novo femoropopliteal lesions.

OBJECTIVES: We analyzed the 2-year clinical outcomes of patients with de novo femoropopliteal (FP) lesions who underwent drug-coated balloon (DCB) angioplasty and the angiographic predictors of restenosis. METHODS: This single-center, retrospective, and observational study evaluated 129 de novo FP lesions treated with DCB angioplasty without bailout stenting. Clinical outcomes and risk factors for loss of primary patency were analyzed using univariate and multivariate Cox proportional hazards regression models. RESULTS: The participants were aged 48-93 (mean: 73.6 ± 9.8) years, and 31% were women. Approximately 33% of the patients were receiving regular dialysis, and 35% of the affected limbs had critical ischemia. The mean lesion length was 132 ± 96 mm, and the mean reference vessel diameter (RVD) was 4.7 ± 0.8 mm. Forty-three (33%) limbs had chronic total occlusion of the target artery segment. Fifty-seven (44%) and 72 (56%) lesions were treated with DCB angioplasty using IN.PACT Admiral and Lutonix, respectively. The primary patency and amputation-free survival at 2 years were 59.3% and 89.5%, respectively. RVD was found to be an independent predictor of loss of primary patency. Based on the receiver operating characteristic analysis, an RVD of 4.2 mm was the best predictor of loss of primary patency at 2 years. CONCLUSIONS: The short-term clinical outcome of DCB angioplasty for de novo FP lesions was acceptable. Moreover, an RVD of <4.2 mm was an independent predictor of restenosis after DCB angioplasty.

Impact of "black rock" on clinical outcomes after endovascular therapy for de novo calcified femoropopliteal lesions.

The relationship between severity of calcification and clinical outcomes after endovascular therapy (EVT) for femoropopliteal lesions is well known. We often encounter dense calcifications in our daily practice, which are darker than normal calcifications on angiography. Accordingly, we named it "black rock" (BR), and investigated its impact on clinical outcomes after EVT. We retrospectively analyzed 677 lesions in 495 patients who underwent EVT for de novo calcified femoropopliteal lesions at our hospital between April 2007 and June 2020. BR is defined as a calcification which is 1 cm or more in length, occupies more than half of the vessel diameter, and appears darker than the body of the femur on angiography. Propensity score matching analysis was performed to compare clinical outcomes between lesions with BR [BR (+) group] and without BR [BR (-) group]. A total of 119 matched pairs of lesions were analyzed. Primary patency at 2 years was significantly lower in the BR (+) group than in the BR (-) group (48% vs. 75%, p = .0007). Multivariate analysis revealed that the presence of BR [hazard ratio (HR) = 2.23, 95% confidence interval (CI); 1.48-3.38, p = .0001], lesion length (HR = 1.03, 95%CI; 1.00-1.06, p = .0244), and no scaffold use (HR = 1.58, 95%CI; 1.06-2.36, p = .0246) were predictors of restenosis. The presence of BR is independently associated with clinical outcomes after EVT for de novo calcified femoropopliteal lesions.

Predictive performance of J-Calc-CTO score for guidewire crossing through chronic total occlusion lesions within 30 minutes: J-CTO score modified by computed tomography coronary angiography.

The original J-CTO score predicts the difficulty of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) lesions, but the grade of calcification has not been fully evaluated. We examined 137 patients (141 CTO lesions) who underwent coronary computed tomography angiography (CTA) pre-PCI between October 2016 and October 2021. They were randomly divided into derivation (n = 94) and validation (n = 47) groups. The degree and distribution of calcification in the occluded segment were assessed using CTA. The calcified index was defined as calcium volume divided by the length of the occluded segment. We created the J-Calc-CTO score consisting of calcification parameters associated with 30-min wire crossing in the derivation group. The validity of the J-Calc-CTO score was compared with that of the original J-CTO score using c-statistics. The procedural success rate was 96%, and 30-min wire crossing during the procedure was achieved in 29%. Dense calcification (calcified-index >12) (odds ratio [OR]: 4.63; 95% confidence interval [CI]: 1.24-22.2; p = 0.04) and calcification in the center of the lumen (OR: 7.25; 95% CI: 1.48-32.1; p = 0.02) were independently associated with 30-min wire crossing as variables evaluated using CTA. The J-Calc-CTO score was created by adding 1 point to the two parameters in place of "calcification" in the original J-CTO score. The J-Calc-CTO score showed a higher predictive value of 30-min wire crossing than the J-CTO score in the derivation (c-statistics; 0.836 vs. 0.670; p > 0.01) and validation groups (c-statistics; 0.879 vs. 0.767, p > 0.01). The degree and distribution of calcification evaluated using CTA refined the predictive value of the original J-CTO score for 30-min wire crossing.

Impact of Chocolate percutaneous transluminal angioplasty balloon on vessel preparation in drug-coated balloon angioplasty for femoropopliteal lesion.

PURPOSE: To compare the impact of Chocolate and conventional balloons on vessel preparation in percutaneous transluminal angioplasty. MATERIALS AND METHODS: This single-center retrospective study included 111 endovascular therapy consecutive cases of femoropopliteal lesions using drug-coated balloon strategy with a 1:1 pre-dilation balloon diameter between February 2020 and August 2021, divided into the Chocolate percutaneous transluminal angioplasty (n = 48) and conventional (n = 63) groups. Before the availability of Chocolate balloons in Japan (December 2020), a standard semi-compliant or non-compliant balloon was used for vessel preparation. The primary endpoint was rate of severe dissection after pre-dilatation. Secondary endpoints were angiographic percent diameter stenosis, bailout stent rate, primary patency rate, and freedom from target-lesion-revascularization rate at six months. RESULTS: There was no significant difference in patient and lesion characteristics. The procedural characteristics comprised balloon length 90 ± 37 and 149 ± 95 mm (P = 0.004) and inflation pressure 11 ± 3 and 16 ± 7 atm (P < 0.001) in the Chocolate and conventional groups, respectively. Regarding primary endpoint, rates of severe dissection were 4.2% and 25% (P = 0.003); regarding secondary endpoints, percent diameter stenosis was 18 ± 15% and 20 ± 17% (P = 0.409), and the rate of bailout stenting was 2.1% and 15.9% (P = 0.016) in the Chocolate and conventional groups, respectively. The primary patency rates at six months were 89.1% and 85.2% (P = 0.670), and freedom from target-lesion-revascularization rate at six months was 100% and 92.8% (P = 0.691) in the Chocolate and conventional groups, respectively. CONCLUSION: Chocolate percutaneous transluminal angioplasty balloons reduce the rate of severe dissection while maintaining a sufficient dilatation effect during drug-coated balloon vessel preparation.

Accuracy of quantitative vessel analysis in endovascular treatment for femoropopliteal lesions.

BACKGROUND: Our aim was to evaluate the accuracy of quantitative vessel analysis (QVA) in measuring the reference vessel diameter (RVD) of femoropopliteal lesions. METHODS: Between October 2014 and September 2015, 30 consecutive femoropopliteal lesions in 25 patients who underwent endovascular therapy (EVT) under intravascular ultrasound (IVUS) guidance were analyzed. RVDs measured using QVAsheath (calibrated using a 6-Fr sheath in the common femoral artery) and QVAruler (calibrated using a ruler on the angiography table) were compared to those obtained using IVUS as the reference values. RESULTS: The mean QVAsheath-measured RVD was significantly larger than the mean IVUS-measured RVD (5.34±1.29 vs. 5.07±1.20 mm, P=0.001). In contrast, mean QVAruler-measured RVD was 4.60±1.04 mm, which was significantly smaller than both the mean IVUS- and mean QVAsheath-measured RVD (both P<0.001). Bland-Altman analysis revealed that the 95% limits of agreement versus IVUS ranged from -0.94 to 1.49 mm for QVAsheath and -1.69 to 0.76 mm for QVAruler, respectively. Agreement with tolerance of ±1.00 mm accounted for 88% of QVAsheath and 83% of QVAruler (P=0.60). The difference between QVA- and IVUS-measured RVDs was inversely correlated with the distance from the table (P=0.029 for QVAsheath and P=0.003 for QVAruler). CONCLUSIONS: The accuracy of both QVAsheath and QVAruler in measuring RVD were similarly suboptimal. Over- and under-estimation of RVD is not rare in QVA.

Scoring model to predict low image quality of drug-eluting stent evaluated by computed tomography coronary angiography.

Evaluation of in-stent restenosis (ISR) by computed tomography coronary angiography (CTCA) is less invasive but often impossible. We aimed to create a scoring model for predicting which drug-eluting stents (DES) cannot be evaluated with CTCA. We enrolled 757 consecutive implanted DES assessed with CTCA. Non-diagnostic evaluation was defined as poor/not evaluative by two different observers. These stents were randomly divided into a derivation (n = 379) and validation (n = 378) group. In the derivation group, we assessed predictors using logistic regression analysis and created a scoring model that would stratify non-diagnostic evaluation of DES-ISR. The validity of this scoring model was evaluated in the validation group using receiver-operating characteristic analysis. The percentage of non-diagnostic stents was 19/21% in the derivation/validation group (p = 0.71). Non-diagnostic evaluation was independently associated with implanted stent diameter (2.25-2.5. vs. 2.5-3 vs. > 3.0 mm), severe calcification, stent-in-stent lesion, and type of DES (stainless vs. CoCr vs. PtCr) in the derivation group. The predicting system of implanted DES non-diagnostic by CTCA (PIDENT) for non-diagnostic evaluation, including these four baseline factors, was derived (C-statistic = 0.86 in derivation group, cutoff: 8 points). The PIDENT score had a high predictive value for non-diagnostic DES in the validation model (C-statistic = 0.87, sensitivity 86%, specificity 74%, cutoff 8 points, p < 0.001). The PIDENT score, consisting of baseline characteristics including implanted stent diameter, severe calcification, stent-in-stent lesion, and type of DES, could identify non-diagnostic evaluation of DES-ISR with CTCA. The PIDENT score was valuable in reducing nonevaluable and meaningless CTCA for DES-ISR.

Scoring Model to Predict Major Amputation in Patients With Chronic Limb-Threatening Ischemia at Wound, Ischemia, and Foot Infection Clinical Stage 4 After Endovascular Therapy.

PURPOSE: We investigated the predictors of major amputation (MA) at 1 year and prepared a scoring model to stratify the clinical outcomes of chronic limb-threatening ischemia (CLTI) patients at wound, ischemia, and foot infection (WIfI) clinical stage 4 after endovascular therapy (EVT). MATERIALS AND METHODS: This study was a retrospective, observational study performed at a single center. A total of 353 CLTI patients (390 limbs) were treated with EVT between April 2007 and December 2016. Among these, limbs at WIfI clinical stages 1, 2, and 3 were excluded, and 194 limbs at WIfI clinical stage 4 (49.7%) were enrolled. The primary endpoint was major amputation (MA) free rate at 1 year. Predictors of MA at 1 year was evaluated by Cox proportional hazard analysis. RESULTS: At 1 year, the incidence of MA was 18.0% (35 limbs). Cox proportional hazard analysis revealed that hemodialysis (hazard ratio [HR] 2.63; 95% confidence interval [CI], 1.24-5.58; p=0.012), fI3 (HR 2.54; 95% CI, 1.28-5.06; p=0.008), toe wounds (HR 0.29; 95% CI, 0.094-0.88; p=0.029), and visible blood flow to the wound (HR 0.43; 95% CI, 0.21-0.89; p=0.023) were associated with MA. We assigned 1 point for positive predictors of MA, hemodialysis, and fI3; 1 point was deducted for negative predictors of MA, toe wounds, and visible blood flow to the wound. A score of -2 or -1, was defined as the low-risk group, 0 was defined as the intermediate-risk group, and +1 or +2 were defined as the high-risk group. At 1 year, MA free rate, wound healing rate, and amputation-free survival rate were stratified according to a scoring model. MA free rate was 96.6% in low-risk, 72.4% in intermediate-risk, and 67.3% in high-risk (p<0.001); wound healing rate was 67.8% in low-risk, 27.6% in intermediate-risk, and 4.1% in high-risk (p<0.001); amputation-free survival rate was 65.3% in low-risk, 44.8% in intermediate-risk, and 18.4% in high-risk (p<0.001). CONCLUSIONS: The scoring model based on the predictors of MA stratified clinical outcomes in CLTI patients at WIfI clinical stage 4.

ULSOSEAL Technique: A Unique Technique to Achieve Hemostasis Using ExoSeal in High-Risk Patients after Common Femoral Artery Puncture.

This study aimed to assess the safety and feasibility of the ULtrasound-guided uSe Of exoSEAL technique (ULSOSEAL technique) in patients at a high risk of complications following the use of ExoSeal. ExoSeal is a novel, completely extravascular hemostatic device that can treat punctures of the common femoral artery; however, it is not preferable for use in cases that require hemostasis of complex puncture sites. From November 2019 to August 2020, the ULSOSEAL technique was performed in 35 patients with implanted stents (6 patients, 17%), severe calcification (32 patients, 91%), and plaque (7 patients, 20%) around the puncture site; the presence of these conditions is usually undesirable when using ExoSeal. The antegrade approach was used in 22 patients (71%). The size of the ExoSeal used was 5 Fr (13 patients, 37%), 6 Fr (21 patients, 60%), and 7 Fr (1 patient, 2%). Technical success was achieved in 34 patients (97%), while ExoSeal malfunction occurred in 1 patient. There was no incidence of vessel occlusion, pseudoaneurysm, arteriovenous fistula, infection, and secondary bleeding. One patient developed a hematoma (>5 cm in size); however, it occurred before the use of ExoSeal due to side leakage from the inserted sheath. The ULSOSEAL technique was safe and feasible for hemostasis in patients who were considered unsuitable for the ExoSeal device.

The feasibility of the flower stenting technique for ostial lesions of the common iliac artery.

BACKGROUND AND AIMS: A balloon-expandable stent (BES) is generally used for ostial lesions of the common iliac artery (CIA) owing to the positional ease of stent adjustment. However, there are potential risks such as vessel dissection and perforation due to vessel overstretching during. In our hospital, we performed endovascular therapy (EVT) for CIA ostial lesions via a novel method named "the flower stenting method," using a self-expandable stent. This study aimed to analyze the efficacy and safety of this method. METHODS: This study was single-center, retrospective, and observational. We enrolled 83 patients (91 limbs) who underwent EVT with SMART stent (Cordis, Miami, Florida) for CIA ostial lesions from 2007 to 2014. The primary endpoint was the rate of freedom from target lesion revascularization (TLR) in 5 years, and the secondary endpoint was the success rate of stent placement for the CIA ostium. RESULTS: The average patient age was 72.3 ± 9.4 years, 71% of the patients were men, 19% were receiving hemodialysis, and 60% had diabetes. Additionally, 38% of the lesions were Trans-Atlantic Inter-Society Consensus C/D lesions, while 37% were chronic total occlusion lesions. The average lesion length was 36 ± 23 mm, and the average vessel diameter was 10.7 ± 1.4 mm. The rate of freedom from TLR was 97.3% at 5 years, and the success rate of only stent placement was 90.1%. CONCLUSION: The flower stenting method leads to acceptable outcomes and is useful for accurate stent deployment.

Frequency, predictors, and effect of the slow-flow phenomenon after drug-coated balloon angioplasty for femoropopliteal lesions.

Drug-coated balloon (DCB) angioplasty for femoropopliteal (FP) lesions has been available in Japan since 2018. In daily practice, we encountered cases of the slow-flow phenomenon after DCB angioplasty. However, no data regarding the slow-flow phenomenon after DCB angioplasty for FP lesions are available. This study aimed to investigate the frequency, predictors, and effect of the slow-flow phenomenon following DCB angioplasty for FP lesions. This single-center, retrospective, observational study analyzed 88 FP lesions treated by DCB angioplasty between April 2018 and July 2019. Patients were divided into the slow-flow group (n = 7) and non-slow-flow group (n = 81) and were analyzed. The primary endpoint was primary patency at 6 months. The slow-flow phenomenon was observed in seven cases (8.0%). The slow-flow group had higher incidence rates of critical limb ischemia (CLI) (71% vs. 25%, p < 0.01), chronic total occlusion (CTO) lesions (86% vs. 26%, p < 0.01), and poor tibial vessel runoff (86% vs. 33%, p < 0.01) and had a longer DCB length (237 ± 56 mm vs. 159 ± 97 mm, p = 0.03) than the non-slow-flow group. The primary patency rate at 6 months was 71% in the slow-flow group and 91% in the non-slow-flow group (p = 0.09). The rate of freedom from target lesion revascularization at 6 months was 71% in the slow-flow group and 97% in the non-slow-flow group (p < 0.01). The amputation-free survival rate at 6 months was 71% and 95% (p = 0.02), whereas the survival rate at 6 months was 71% and 95% (p = 0.02). The incidence rate of the slow-flow phenomenon after DCB angioplasty for FP lesions was 8.0%. CLI, a CTO lesion, poor tibial vessel runoff, and total DCB length were associated with the slow-flow phenomenon. Our results indicate that the slow-flow phenomenon is associated with poor short-term clinical outcomes.

Stentless Strategy by Drug-Coated Balloon Angioplasty following Directional Coronary Atherectomy for Left Main Bifurcation Lesion.

AIMS: We aimed to evaluate the efficacy of stentless strategy by drug-coated balloon (DCB) angioplasty following directional coronary atherectomy (DCA) for left main (LM) bifurcation lesions. METHODS: A total of 38 patients who underwent DCB angioplasty following DCA for LM bifurcation lesions were retrospectively enrolled. The primary endpoint was target vessel failure (TVF) at 12 months. Secondary endpoints included procedure-related major events during the hospitalization, major adverse cardiac events at 12 months, ischemia-driven target lesion revascularization (TLR) at 12 months, and bleeding complications defined as the Bleeding Academic Research Consortium criteria ≥2 at 12 months. RESULTS: Among these 38 lesions, 31 lesions were de novo LM bifurcation lesions and 7 lesions were stent edge restenosis at the left anterior descending (LAD) ostium. The mean % plaque area (%PA) after DCA was 44.0 ± 7.4%. TVF at 12 months occurred in 1 lesion (3.2%) of de novo LM bifurcation lesion and in 3 lesions (42.9%) of stent edge restenosis at the LAD ostium. All events of TVF were ischemia-driven TLR by percutaneous coronary intervention. Among 4 TLR cases, %PA after DCA was high (55.9%) in the de novo LM bifurcation lesions; on the other hand, %PA after DCA was low (42.4%, 38.7%, and 25.7% in the 3 cases) in stent edge restenosis at the LAD ostium. No procedure-related major events were observed during hospitalization. There was no cardiac death, no myocardial infarction, no coronary artery bypass grafting, and no bleeding complications at 12 months. CONCLUSIONS: Stentless strategy by DCB angioplasty following DCA for de novo LM bifurcation lesions resulted in acceptable outcomes. On the other hand, its efficacy was limited for stent edge restenosis at the LAD ostium even after aggressive debulking by DCA.

Atrial Fibrillation is Associated with Femoropopliteal Totally Occlusive In-Stent Restenosis: A Single-Center, Retrospective, Observational Study.

INTRODUCTION: The proportion of patients with comorbid atrial fibrillation (AF) and peripheral artery disease (PAD) has increased in this era. This study aimed to assess the relationship between AF and totally occlusive in-stent restenosis (ISR) in femoropopliteal (FP) lesions. METHODS: In this study, 363 patients (461 stents) who underwent endovascular therapy with de novo stent implantation in our hospital between April 2007 and December 2016 were retrospectively evaluated. The patients were divided into two groups according to the AF status (AF group, 61 patients; sinus group, 302 patients). The primary endpoint was the incidence of totally occlusive ISR within 3 years. The secondary endpoint was the incidence of acute limb ischemia (ALI) due to FP stent occlusion. RESULTS: Baseline characteristics were similar, except for higher age and a lower prevalence of dyslipidemia in the AF group. The incidence of a totally occlusive ISR was higher in the AF group than in the sinus group (29.5% vs. 14.6%, p=0.004). A multiple Cox regression model suggested that presence of AF (hazard ratio, 2.10) and CTO lesion (hazard ratio, 1.97) which were the independent predictors of a totally occlusive ISR within 3 years. The incidence of ALI was significantly higher in the AF group than in the sinus group (3.9% vs. 0%, p=0.0001). In the AF group, the introduction of an anticoagulant did not prevent the occurrence of totally occlusive ISR (p=0.71) for ALI (p=0.79). CONCLUSIONS: AF is independently associated with totally occlusive ISR of FP stents; however, anticoagulant use does not prevent stent occlusion.

Vascular Response after Directional Coronary Atherectomy for Left Main Bifurcation Lesion.

AIMS: To evaluate the vascular response after directional coronary atherectomy (DCA) for left main (LM) bifurcation lesion. METHODS: This study was a retrospective, single-center study enrolling 31 patients who underwent stentless therapy using DCA followed by drug-coated balloon (DCB) angioplasty for LM bifurcation lesion. We compared intravascular ultrasound (IVUS) findings before and after DCA. RESULTS: After DCA, the lumen and vessel areas significantly increased, whereas the plaque area (PA) and %PA were significantly reduced. When the lesions were divided into small vessel and large vessel groups using the median value of the vessel area, the maximum balloon pressure of the DCA catheter was greater in the large vessel group. Changes in the lumen and vessel areas were also significantly greater in the large vessel group. On the other hand, the changes in PA and %PA were similar between groups. CONCLUSIONS: The main vascular responses associated with lumen enlargement after DCA were plaque reduction and vessel expansion. Contribution of vessel expansion to lumen enlargement was larger than the effect of plaque reduction in large vessel lesions.

Usefulness of ultrasound-guided intraluminal approach for long occlusive femoropopliteal lesion.

To investigate the usefulness of ultrasound-guided (USG) intraluminal approach for femoropopliteal (FP) lesion. 64 patients (73 limbs) with de novo long occlusive (> 15 cm) FP lesions underwent USG intralumial approach from April 2012 to October 2016. Periprocedural intravascular ultrasound findings were collected. Clinical outcome and predictors of restenosis after USG intraluminal approach for de novo long occlusive FP lesion were investigated. Among the study participants, 34% were female, 50% had diabetes mellitus, and 10% received hemodialysis. Lesion and chronic total occlusion (CTO) lengths were 222 ± 55 mm and 201 ± 55 mm, respectively. Procedural success was achieved in 72 lesions (99%). Distal puncture was performed in 7 limbs (10%). The proportion of within-CTO intraplaque, subintimal, and medial routes were 87 ± 21%, 9 ± 15%, and 4 ± 11%, respectively. Primary patency was 71% and 69% at 1 and 2 years. Multivariate analysis revealed that within-CTO intraplaque route proportion [hazard ratio (HR) 0.81; 95% confidence interval (CI) 0.67-0.98, p = 0.0339] and lesion length (HR 1.11; CI 1.00-1.22; p = 0.0447) were independent predictors of restenosis.USG intraluminal approach facilitated acquisition of within-CTO intraplaque route in long occlusive FP lesions and could improve clinical outcome.

A Comparative Analysis between Ultrasound-Guided and Conventional Distal Transradial Access for Coronary Angiography and Intervention.

OBJECTIVES: To compare feasibility and safety between ultrasound-guided and conventional distal transradial access (dTRA). BACKGROUND: Distal transradial access, a new technique for coronary angiography (CAG) and percutaneous coronary interventions (PCI), is safe and feasible and will become popular worldwide. Ultrasound-guided dTRA has been advocated to reduce failure rate and access-site complications. However, to date, the comparison of feasibility and safety between ultrasound-guided and conventional dTRA has not been reported. METHOD: Overall, 137 patients (144 procedures) who underwent CAG or PCI using dTRA between September 2018 and February 2019 were investigated. These patients were classified into two groups: C (dTRA with conventional punctures; 76 patients, 79 procedures) and U (dTRA with ultrasound-guided punctures; 61 patients, 65 procedures) groups. Successful procedural rate, procedural outcomes, and complication rate during hospital stays were compared between the two groups. RESULTS: The procedural success rate was significantly higher in the U group than in the C group (97% vs. 87%, P=0.0384). However, the rate of PCI, puncture time, total fluoroscopy time, the volume of contrast medium, the rate of access-site ecchymosis, and incidence of nerve disorder were similar between the two groups. Additionally, radial artery occlusion after the procedure did not occur in this study. CONCLUSION: The ultrasound-guided dTRA for CAG or PCI was associated with a lower failure rate than conventional dTRA. However, there were no significant differences in puncture time and complication rate between the two procedures.

Use of the orbital atherectomy system backed up with the guide-extension catheter for a severely tortuous calcified coronary lesion.

A 68-year-old man was scheduled to undergo percutaneous coronary intervention for in-stent total occlusion of the severely tortuous right coronary artery. Intravascular ultrasound revealed heavy in-stent calcification. Lesion atherectomy was required; however, severe proximal vessel tortuosity was detected. We introduced a 7-Fr guide-extension catheter beyond the severely tortuous part and performed rotational atherectomy with a 1.5 mm burr. However, the balloon could not expand; therefore, we changed to an orbital atherectomy system. Subsequently, the balloon successfully expanded, and intravascular ultrasound revealed an enlarged lumen. Severe proximal vessel tortuosity limits the use of atherectomy devices; however, a guide-extension catheter delivers the atherectomy device beyond the tortuosity. The delivery of the orbital atherectomy system inside the guide-extension catheter is easy due to its low profile; the debulking effect increases with the number of passes and rotational speed. This strategy is a useful option for treating severe calcified lesions with proximal vessel tortuosity.

Additional debulking efficacy of low-speed rotational atherectomy after high-speed rotational atherectomy for calcified coronary lesion.

We aimed to evaluate the additional debulking efficacy of low-speed rotational atherectomy (RA) after high-speed RA by using intravascular imaging. A total of 22 severe calcified coronary lesions in 19 patients (age, 74 ± 10 years; 74% male) were retrospectively analyzed. All of these lesions underwent RA under optical coherence tomography (OCT) or optical frequency domain imaging (OFDI) guidance. At first, we performed high-speed RA with 220,000 rpm until the reduction of rotational speed disappeared; then, low-speed RA with 120,000 rpm using the same burr size was performed. OCT or OFDI was performed after both high-speed and low-speed RAs, and the minimum lumen area were compared. The initial and final burr sizes of high-speed RA were 1.5 (1.5-1.75) and 1.75 (1.5-2.0) mm, respectively. The number of sessions, total duration time, and maximum decreased rotational speed during high-speed RA were 11 ± 5 times, 113 ± 47 s, and 4000 (3000-5000) rpm, respectively. During low-speed RA, the number of sessions, total duration time, and maximum reduction of rotational speed were 3 ± 1 times, 32 ± 11 s, and 1000 (0-2000) rpm, respectively. The minimum lumen area was similar between after high-speed and after low-speed RA [2.61 ± 1.03 mm2 (after high-speed RA) vs. 2.65 ± 1.00 mm2 (after low-speed RA); P = 0.91]. Additional low-speed RA immediately after sufficient debulking by high-speed RA was not associated with increased lumen enlargement. There was no clinical efficacy of low-speed RA after high-speed RA.

Sustained drug retention after paclitaxel-coated balloon angioplasty for superficial femoral artery disease: Follow-up intravascular imaging.

A 63 year-old woman with claudication underwent endovascular therapy for diffuse stenosis of the right superficial femoral artery in our hospital. We performed paclitaxel-coated balloon angioplasty using the IN.PACT™ Admiral™ and achieved acceptable results. After 42 days, we performed follow-up optical frequency domain imaging for the right superficial femoral artery lesion treated with paclitaxel-coated balloon and observed several high-intensity regions with attenuation on the lumen surface. Sustained drug availability is a notable characteristic of paclitaxel-coated balloon. To the best of our knowledge, this is the first report on the visualization of sustained drug retention on the lumen surface using follow-up optical frequency domain imaging after paclitaxel-coated balloon angioplasty in a human patient with superficial femoral artery disease.

Usefulness of a Guide Extension Catheter in Endovascular Therapy of Infrapopliteal Lesions.

Guide extension catheters have been available since 2015 for peripheral endovascular intervention. These devices are commonly used for active backup support. We successfully managed 2 cases of infrapopliteal arterial disease with the assistance of a guide extension catheter. In a patient with a posterior tibial artery occlusion, early elastic recoil occurred after balloon dilatation. We then deployed the guide extension catheter to maintain blood flow while ballooning for 15 min, resulting in good blood flow to the toes after device removal. Another patient had a severely calcified stenotic anterior tibial artery lesion. Although a guidewire could be advanced to the lesion, no device could be passed through the calcification. Using the guide extension catheter, we then safely delivered a 0.035-inch guidewire's tail to drill through the calcification. Thereafter, a balloon could be passed, and successful angioplasty was achieved. These cases illustrate the usefulness of a guide extension catheter in endovascular therapy of complex infrapopliteal lesions.

Clinical Impact and Predictors of the Slow-Flow Phenomenon after Endovascular Treatment of Infrapopliteal Lesions Using the Crosser Catheter in Patients with Critical Limb Ischemia.

PURPOSE: To determine the clinical impact and predictors of slow flow after endovascular treatment (EVT) using the Crosser catheter for debulking infrapopliteal lesions associated with critical limb ischemia. MATERIALS AND METHODS: This retrospective study included 65 patients with critical limb ischemia (70 limbs, 90 infrapopliteal lesions), who underwent EVT using the Crosser catheter between November 2011 and February 2017. The Crosser catheter was used when the balloon catheter could not be passed through the lesion or could not be dilated sufficiently. Slow flow was evaluated after atherectomy using Crosser and was defined as delayed antegrade flow to the foot (total number of cine frames >35). RESULTS: Following atherectomy, slow flow developed in 37 infrapopliteal lesions (41.1%). Despite secondary treatment, slow flow persisted in 29 of 37 lesions (78%). After atherectomy using the Crosser catheter, the balloon could be passed through the lesion in all cases. The wound healing rate at 1 year after EVT (overall, 67.8%) was significantly poorer in the presence of slow flow (rate with vs. without slow flow, 45.3% vs. 84.4%, respectively; P = .006), especially among patients with stage ≥3 baseline wound, ischemia, and foot infection. The active length of the Crosser catheter was a predictor of slow flow (odds ratio, 1.05; 95% confidence interval, 1.03-1.08; P < .001), with an optimal cutoff of 100 mm. CONCLUSIONS: Slow flow is associated with a poorer wound healing rate at 1 year, especially for patients with severe baseline ischemia. To reduce the risk of slow flow, the active length of the Crosser catheter should be kept at <100 mm.