Femoropopliteal Arterial Dissections Following FLEX VP and Balloon Angioplasty Versus Balloon Angioplasty Alone: Intravascular Ultrasound Assessment and Correlation With Angiographic Findings.

BACKGROUND: The Flex VP is a longitudinal micro-incision catheter approved for vessel prepping of femoropopliteal arteries and arteriovenous fistulas. In this study, we evaluated the presence of deep dissections (adventitia) using IVUS in patients undergoing Flex VP followed by angioplasty (PTA) versus PTA alone. METHODS: 17 patients (20 limbs) with femoropopliteal artery (FP) disease were prospectively and consecutively included (10 limbs received PTA followed by 10 limbs that received FLEX VP microincision catheter treatment followed by adjunctive PTA). Dissections post PTA, FLEX VP and FLEX VP+ PTA were evaluated using intravascular ultrasound (iDissection classification) and angiographically (NHLBI classification) by core laboratory. The evaluated segment of the vessel was prespecified at 10 cm at the most severe lesion location. Statistical differences were analyzed between the 2 groups at each appropriate procedural point for dissections, minimal luminal diameter (MLD), minimal luminal area (MLA), and residual stenosis. Statistical significance was determined by a p-value <0.05. RESULTS: Baseline demographics and angiographic variables were similar between the PTA vs FLEX VP + PTA groups with the exception of more males (87.5 % vs 33.3 %, p = 0.0274) and longer treated length (median 300 mm vs 150 mm, p = 0.0240) in the FLEX VP + PTA group. Lesion length, chronic total occlusions, angiographic and IVUS evaluated segment length for dissections, calcium severity and final balloon pressures and inflation duration were all similar between the 2 groups. Angiographic dissections were similar between the 2 groups but the increase in severe dissections from index to post POBA on IVUS (involving the adventitia) were significantly more for PTA when compared to FLEX VP + PTA (0 to 12 and 0 to 1 respectively, p = 0.0353). Bailout stenting was statistically similar for PTA as compared to FLEX VP + PTA per core lab evaluation (50 % vs 20 %, p = 0.3498). Minimal luminal area (MLA) gain by IVUS was similar between the 2 groups following FLEX VP + PTA vs PTA (7.4 mm2 vs 6.5 mm2, p = 0.7250). No serious major adverse events occurred in either group. CONCLUSION: Vessel prepping with the FLEX VP + PTA vs PTA yielded lower rates of adventitial dissections as seen on IVUS. The long-term outcomes of these findings remain unclear.

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.

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.