Intravascular Ultrasound Assessment and Correlation With Angiographic Findings of Arterial Dissections Following Auryon Laser Atherectomy and Adjunctive Balloon Angioplasty: Results of the iDissection Auryon Laser Study.

BACKGROUND: Femoropopliteal arterial angiographic dissections with the use of the Auryon laser atherectomy system (previously the B-laser) have been infrequent and non-flow limiting. However, the pattern of these dissections (depth and arc) using intravascular ultrasound remains unknown. MATERIALS AND METHODS: We prospectively enrolled 29 patients in the iDissection Auryon study. The primary objective was to define the occurrence of new adventitial injury with intravascular ultrasound (IVUS). Secondary objectives included distal embolization and bailout stenting as judged by the operator because of 30% or more residual narrowing and/or NHLBI (National Heart, Lung, and Blood Institute) angiographic dissection C and higher. Core laboratory analysis was carried on all cases except for 1 patient (that crossed over to Jetstream atherectomy). Dissections were classified according to the iDissection classification as involving the intima (A), media (B), and adventitia (C) and ≤ 180-° arc (1) or >180-° arc (2). Overall, 22 of 29 patients had an embolic filter (per protocol). RESULTS: Median lesion and treated lengths were 100.0 and 150.0 mm, respectively. Vessel diameter by IVUS was 6.5 ± 1.5 mm. Chronic total occlusion (CTO) was present in 24.1% of cases. The arc of calcium was: no calcium in 27.6%, <90° in 13.8%, 90° to 180° in 20.7%, and >180° in 34.4%. Lesion severity was reduced to a median of 14% post laser and adjunctive percutaneous transluminal angioplasty (PTA) from a baseline of 76%. Bailout stenting occurred in 6 of 28 (21.4%) patients (3 for dissections, 2 for residual >30%, and 1 for both) and primary stenting in 1 of 28 (3.6%). By IVUS, there were 9 new dissections post laser (1 adventitial; 3≥180°) and 21 new dissections post laser and PTA (3 adventitial; 1≥180°). No distal embolization requiring treatment was seen and no macrodebris ≥2 mm was recovered in the filters. CONCLUSION: The Auryon laser atherectomy system had minimal rate of adventitial injury despite complex disease with relatively low bailout stent rate and no clinically significant macrodebris.

Optimal Vessel Sizing and Understanding Dissections in Infrapopliteal Interventions: Data From the iDissection Below the Knee Study.

PURPOSE: To investigate if imaging with intravascular ultrasound (IVUS) yields a more accurate estimate of vessel diameter and the presence of dissections than angiography after intervention in the infrapopliteal arteries. MATERIALS AND METHODS: A prospective, single-center study enrolled 20 consecutive patients (mean age 74.1±12.4 years; 12 women) with infrapopliteal disease who were treated with percutaneous transluminal angioplasty (PTA; n=10) or orbital atherectomy (OA) followed by PTA (n=10). The majority of patients were hypertensive and half were diabetic. The overall lesion length was 7.3±6.3 cm, and the diameter stenosis was 80.3%±22.1%. The baseline characteristics did not differ between the groups. Vessel diameters were measured using IVUS from the internal elastic lamina (IEL) to the IEL. IVUS was performed at baseline, post PTA or OA, and post OA+PTA. Quantitative vascular angiography (QVA) and IVUS were analyzed by a core laboratory. Dissections on cine images were categorized based on the National Heart Lung and Blood Institute (NHLBI) classification, while the arc and depth were used to characterize dissections on IVUS images. RESULTS: Mean vessel diameter by QVA was 2.9±0.6 vs 4.0±1.0 mm by IVUS according to the core laboratory (mean difference 1.1±0.9, p<0.001). On angiography, there were 7 dissections after PTA (6 C, 1 D), 1 dissection after OA (1 B), and 2 dissections after OA+PTA (1 A, 1 B; p=0.028 vs post PTA). IVUS uncovered 3.8 times more dissections than seen on angiography. There were 23 dissections after PTA (18 intima, 3 media, 2 adventitia), 12 dissections after OA (8 intima, 1 media, 3 adventitia), and 11 dissections following OA+PTA (7 intima, 1 media, 3 adventitia; p=0.425 vs PTA). Bailout stenting (all due to angiographic dissections ≥C) was necessary in 6 of the PTA cohort and none of the OA+PTA group. CONCLUSION: In addition to underestimating the infrapopliteal vessel diameter by ~25%, angiography underappreciated the presence and severity of post-intervention dissections vs IVUS, particularly in the OA+PTA group.

Prospective, Multi-center, Single-Arm Study of the Auryon Laser System for Treatment of Below-the-Knee Arteries in Patients With Chronic Limb-Threatening Ischemia: 30-Day Results of the Auryon BTK.

The 355 nm Auryon laser (AngioDynamics, Inc., Latham, New York) has been shown to be effective and safe in treating various morphology lesions in the femoropopliteal arteries. There are limited data on the Auryon laser in treating below-the-knee (BTK) arteries in patients with chronic limb-threatening ischemia. We present the 30-day efficacy and safety findings from the ongoing Auryon BTK study. Patients with chronic limb-threatening ischemia were prospectively enrolled in the Auryon BTK study between March 2022 and February 2023 in 4 US centers after obtaining written informed consent. The primary safety end point included major adverse limb events + postoperative death at 30 days, defined as a composite of all-cause death, major amputation, and target vessel revascularization. Demographic, procedural, angiographic, and outcome data were collected. A total of 60 patients (61 lesions) were treated. The mean age was 74.6 ± 10.3 years, with 65.0% men, 58.3% with diabetes, 43.3% Rutherford Becker (RB) IV, and 56.7% RB V. Of the 61 lesions, 59% had severe calcification, 31.1% were chronic total occlusions, and 90.2% were de novo disease. The baseline diameter stenosis was 80.2 ± 16.4%, after laser 57.4 ± 21.7%, and after final treatment 24.0 ± 23.1% (p <0.0050). The primary performance end point showed a procedure success rate of 37 of 68 (63.8%). Bailout stenting occurred in 1 of 61 lesions (1.6%). The RB category was 100% RB IV or higher at baseline versus 35.3% at 30 days. At 30 days, there was no target vessel revascularization and the patency was 88.9% (Peak Systolic Velocity Ratio (PSVR) ≤2.4). In conclusion, the Auryon laser is safe and relatively effective in treating BTK lesions with minimal complications.

Location of Dissections Post Balloon Angioplasty in Patients With Femoropopliteal Arterial Disease as Seen on Intravascular Ultrasound.

We reviewed images from our intravascular ultrasound core lab to define the various locations of dissections in femoropopliteal arteries post balloon angioplasty in relation to plaque morphology.

Dissections in Peripheral Vascular Interventions: A Proposed Classification Using Intravascular Ultrasound.

Dissections following interventions in the infrainguinal arteries occur very frequently and are mostly under-appreciated on angiographic imaging. Media and external elastic lamina injury can contribute to loss of patency, and intravascular ultrasound (IVUS) can identify this type of injury. The circumference of injury also has been proposed to be a predictor of outcome. We therefore propose a classification combining depth of injury from intima to adventitia with circumference of dissection. This classification exhibits six dissection grades (A1, A2, B1, B2, C1, and C2) as seen on IVUS (the "iDissection" classification).

Tryton dedicated bifurcation stent in treatment of unprotected distal left main bifurcation disease.

Percutaneous coronary interventions involving coronary bifurcation lesions are more complex and associated with adverse outcomes (both angiographic and clinical) compared to non-bifurcation lesions. Tryton, a dedicated bifurcation stent, has been introduced with the aim to simplify treatment of bifurcation lesions. Tryton stent in combination with conventional drug eluting stent is safe and associated with reduced stenosis and bail-out stenting of side branch compared to provisional stenting involving a large side. However, little is known regarding safety and efficacy of Tryton stent in left main (LM) bifurcation lesion. We describe two cases of unprotected LM bifurcation stenting using Tryton stent in combination with drug eluting stent.

Intravascular Ultrasound Assessment and Correlation With Angiographic Findings Demonstrating Femoropopliteal Arterial Dissections Post Atherectomy: Results From the iDissection Study.

BACKGROUND: Dissections occur post atherectomy of the infrainguinal arteries. We hypothesized that angiography under-estimates their presence significantly. METHODS: In this prospective pilot study, a total of 15 patients were evaluated by intravascular ultrasound (IVUS) following treatment of femoropopliteal de novo or non-stent restenosis using atherectomy. Eagle Eye Platinum ST IVUS catheters (Philips) were used in this study. Thirteen Jetstream XC atherectomy devices (Boston Scientific) and 2 investigational B-laser atherectomy devices (Eximo Medical) were used. Cine and IVUS images were obtained at baseline, after atherectomy, and after adjunctive balloon angioplasty. Angiographic and IVUS core labs analyzed the images. RESULTS: Mean age was 70.6 ± 8.0 years. Diabetes and claudication were present in 60% and 73%, respectively. Mean baseline, post-atherectomy, and post-adjunctive angioplasty stenosis severity was 71.4%, 38.1%, and 19.7%, respectively (P<.001 for both baseline vs post atherectomy and post atherectomy vs adjunctive angioplasty). Lesion length was 108.5 ± 43.1 mm. Forty-six dissections were identified on IVUS post atherectomy vs 8 dissections on angiogram (P<.01) (ratio, 5.75 to 1). Post adjunctive angioplasty, there were 39 dissections on IVUS vs 11 on angiogram (P<.01) (ratio, 3.55 to 1). Of these dissections, 13% and 30.8% were ≥180° in circumference post atherectomy and adjunctive balloon angioplasty, respectively (P=.047). Also, 39.1% and 33.3% involved the media and/or adventitia as seen on IVUS post atherectomy and adjunctive balloon angioplasty, respectively (P=.58). Longer lesions correlated with more dissections post atherectomy on IVUS (P=.03), but not on angiogram (P=.28). CONCLUSION: Dissections post atherectomy are grossly under-appreciated on angiogram when compared to IVUS. A multicenter registry correlating these findings with clinical outcomes is needed.

Infrainguinal CTO Recanalization Assessed by Intravascular Ultrasound: Results of the CENTRAL Study.

OBJECTIVES: CENTRAL was a prospective, multicenter, 100 patient study designed to evaluate the ability of a recanalization catheter system to cross chronic total occlusions (CTOs) of the superficial femoral artery while staying within the central vessel lumen. METHODS: The primary endpoint was the successful crossing of a CTO (≥90% of the length) with the recanalization catheter in the central lumen of the superficial femoral artery in at least one-half of the studied patient population, confirmed by intravascular ultrasound. Secondary endpoints included standardized anatomic damage assessment (the TAPE method) and an assessment of the relationship between the percent of CTO crossing and TAPE scores to the rate of target-lesion revascularization (TLR) at 30 days and 6 months. RESULTS: The mean age of the occlusions was 16.6 ± 22.28 months (range, 1-120 months), the average occlusion length reported by the sites was 132.1 ± 87.69 mm (range, 4-300 mm), and a majority of lesions were moderately (42.0%) or severely (32.0%) calcified. In 43/85 (50.6%) of the evaluable intravascular ultrasound images, the recanalization catheter successfully navigated the central lumen of the CTO (ie, ≥90% luminal crossing) with >50% luminal crossing in 64/85 (75.3%) of cases. The 6-month TLR rate was significantly lower in patients where the CTO was crossed ≥90% in the central vessel lumen (4.7%) compared with crossings <90% (20.6%; P=.04). The 6-month TLR rate was 3.5% in patients with a favorable TAPE score of 0-4 and 36.8% with an unfavorable TAPE score of 5-8 (P<.001). CONCLUSION: Use of a recanalization catheter in complex superficial femoral artery CTO crossings achieved intraluminal crossings in >50% of cases and decreased anatomic damage, which appeared to offer a significant advantage in 6-month TLR rates.

Sealed with a kick: a case of posttraumatic coronary artery dissection and cardiomyopathy.

Blunt chest trauma can lead to a variety of cardiac injuries, one of which is nonatherosclerotic myocardial infarction caused by intimal laceration and thrombotic process activation. Here we present a case of anterior myocardial infarction secondary to blunt trauma involving a kick to the chest.

Tissue removal by ultrasound evaluation (the TRUE study): the Jetstream G2 system post-market peripheral vascular IVUS study.

BACKGROUND: Balloon angioplasty and stenting of infra-inguinal lesions is limited by poor long-term patency rates. Atherectomy decreases plaque burden and provides an alternative means of revascularizing patients with peripheral arterial disease. The Jetstream G2™ (Pathway Medical Technologies, Inc., Kirkland, Washington) is a newer rotational aspiration atherectomy device, uniquely combining rotablation with aspiration capability. We evaluated the debulking properties of this device by analyzing changes in the plaque volume and composition and vessel size using intravascular ultrasound (IVUS) and virtual histology (VH). Freedom from target lesion revascularization (TLR) at 6 and 12 months was also evaluated. METHODS AND RESULTS: Eighteen patients with peripheral arterial disease requiring intervention (severe claudication despite optimal medical treatment or critical limb ischemia) were treated with rotational atherectomy. The mean age was 69.6 ± 11 years, 66.7% were male, and 44.4% had diabetes. The mean total plaque volume decreased by 56.6 mm³ (479.8 ± 172.5 mm³ to 423.2 ± 156.6 mm³; p < 0.0001), which resulted in a mean luminal volume increase of 64.3 mm³ (148.4 ± 84.1 mm³ to 212.7 ± 72.1 mm³; p < 0.0001). This was achieved without significant Dotter effect with either technique, as evidenced by the virtually unchanged vessel volume before and after treatment (628.3 ± 158.5 mm³ and 635.9 ± 169.0 mm³, respectively; p = 0.22). There was a significant reduction in fibrotic and fibro-fatty plaque volume, with no appreciable effect on necrotic core and dense calcium. There were no reported procedure-related complications and the 6- and 12-month TLR rate was 11% (2/18). CONCLUSION: Atherectomy with the Jetstream G2 system results in substantial plaque volume reduction by removing fibrotic and fibro-fatty plaque. This resulted in substantial luminal volume expansion without concomitant vessel expansion. There were no major procedure-related complications, along with a relatively low 6- and 12-month rate of TLR. Future studies involving a larger number of patients are warranted to examine the potential clinical benefits of this promising technology.

Peripheral plaque volume changes pre- and post-rotational atherectomy followed by directional plaque excision: assessment by intravascular ultrasound and virtual histology.

Atherectomy in the infra-inguinal peripheral vascular bed may be an effective alternative to the balloon and stent-based approach. The change in plaque volume and composition with rotational atherectomy and directional plaque excision has not been studied. We performed rotational atherectomy (RA) followed by adjunctive plaque excision (PE) in 8 patients with infra-inguinal lesions. Lesions were assessed by quantitative angiography and intravascular ultrasound (IVUS) with virtual histology (VH) pretreatment, post-RA, and post-PE. Paired t-tests were used to assess the change in plaque volume, luminal area and dimensions and overall vessel size. Total plaque volume decreased by 24% (347 +/- 118 to 264 +/- 85 mm(3); p = 0.03), which resulted in a lumen increase of 66% (7.08 +/- 3 to 11.7 +/- 2.8 mm(2); p = 0.006). This was mainly due to PE compared to RA. This was achieved without any significant increase in the overall vessel area (27.4 +/- 6.3 to 28 +/- 6.7 mm(2); p = 0.42). The effect on minimal and maximal luminal diameters was synergistic between RA and PE. Fibrotic and fibrofatty plaque were amenable to PE, whereas necrotic core and dense calcium were less responsive to either atherectomy technique. In conclusion, RA followed by PE result in significant improvements in plaque volume and luminal area and diameter primarily by removing plaque rather than vessel expansion. This is mainly attributable to the removal of fibrotic and fibrofatty plaque.

The impact of coronary artery disease risk factors on intravascular ultrasound-derived morphologic indices of human coronaries.

OBJECTIVE: The relationship of intravascular ultrasound (IVUS)-derived measurements of atherosclerotic plaque to various coronary artery disease (CAD) risk factors is not well known. The purpose of this study was to examine the relationship of percent coronary luminal stenosis by IVUS to other IVUS measures of CAD, as well as the relationship of common IVUS measures of CAD to traditional CAD risk factors. We hypothesized that one or more IVUS measures of CAD might relate more strongly to CAD risk factors than does percent luminal coronary stenosis. METHODS: The records of 897 consecutive patients (57% men, mean age 62 years) who underwent IVUS investigation of their coronary arteries from 1996 through 2001 were retrospectively reviewed. IVUS was performed using a 20-MHz probe (Jomed, Rancho Cordoba, CA) and a manual pull-back technique to image the coronary arteries. Coronary artery remodeling ratio-i.e., the ratio of coronary lesion external elastic membrane cross-sectional area (EEM CSA) to proximal reference artery EEM CSA; plaque burden-i.e., plaque plus media CSA divided by EEM CSA; calcium arc; and percent stenosis of luminal cross-sectional area were measured by a single reader. RESULTS: Percent area stenosis, the most commonly used IVUS parameter, did not correlate with the other three IVUS-derived parameters, nor was it related to any of the CAD risk factors considered. In contrast, remodeling ratio was directly correlated with plaque burden (r=0.22, P<0.001), but inversely related to calcium arc (r=-0.13, P=0.01). IVUS plaque burden was significantly correlated with male gender (P<0.0001) and diabetes mellitus (DM) (P=0.003). In multivariate analyses including age, gender, and CAD risk factors, plaque burden was significantly associated with age, male gender, and DM, but not with chronic renal failure, hypertension, or hypercholesterolemia. The multivariate model also revealed that the calcium arc was significantly associated with male gender and age. These IVUS findings provide anatomic documentation that the traditional CAD risk factors relate more strongly to plaque burden than to percent coronary arterial luminal narrowing.