Femoropopliteal dissection: Fix or prevent?

September 2018

E D U C AT I O N A L S U P P L E M E N T

FEMOROPOPLITEAL DISSECTION: FIX OR PREVENT?

Courtesy of Prof. Stavros Spiliopoulos

This educational supplement has been sponsored by Medtronic. For distribution within Europe only.

Arterial dissection

Arterial dissection after balloon angioplasty: an underestimated cause of excessive stenting and patency loss

By Stavros Spiliopoulos Asst. Professor of Interventional Radiology, Attikon University Hospital, Athens, Greece

Arterial dissection is an immediate complication of balloon angioplasty and is mainly noted in cases of balloon over sizing and treatment of complex calcified lesions.1 However, angioplasty per se creates vessel wall dissection, as its mechanism of action is based on the fragmentation and redistribution of the atherosclerotic plaque within the arterial layers, in order to forcefully increase the diameter of the affected lumen.2

A

s the atheromatous plaque is incompressible, it has been histologically proven that balloon dilatation provokes cracking of the intima and separation from the media, fracture of the internal elastic lamina and dissection of the media.2,3 Therefore, balloon angioplasty by definition causes dissection to various extents, even when technically optimal. In order to describe the degree of arterial dissection in peripheral arterial procedures, physicians have adopted the National Heart, Lung and Blood Institute (NHLBI) classification for coronary dissections which divides dissections into six different types of angiographic appearance.4 Bailout stenting is recommended in types C to F (severe, flow-limiting dissections), in order to avoid imminent lumen reocclusion.

However, immediate thrombosis due to interrupted blood flow is not the only mechanism by which dissection contributes to patency loss. Several studies have demonstrated that postangioplasty dissections are more frequent than believed and are also correlated with the loss of both immediate and long-term patency.

Fujihara et al investigated the various patterns of angiographic dissection and their correlation with long-term outcomes following femoropopliteal angioplasty.5 In only 16% of the cases, dissection was not evident at completion angiography, while NHLBI type A (minor radiolucent areas) and type B dissections (linear dissection) were noted in 19% and 23% of the cases, respectively. Severe, flowlimiting dissections (persistent staining or new filling defects or occlusion) were noted in the

2

remaining 42% of the cases.

Patients with severe type C to E dissections had significantly reduced primary patency rates and more reinterventions at two-years follow-up compared to those with non-severe type A and B dissections. Interestingly, worse outcomes were observed despite the fact that the vast majority of severe dissections underwent bailout stenting (stenting rate: 82% for type C, 87% for type D, 90% for type E and 94% for type F), while many events of patency loss were noted after six- and 12-months follow up, indicating that acute thrombosis is probably not the only mechanism of reocclusion in cases of severe dissection. The authors also reported that treatment of long or occluded lesions and a small vessel diameter (<5mm) were associated with severe dissection.5 These outcomes are in line with previously reported data from the THUNDER trial which correlated severe dissection with poor patency6 but also from the only randomised trial comparing short (30 seconds) versus long (180 seconds) balloon inflation. The authors reported that extensive dissections (extensive dissection membrane, not flow limiting or flow-limiting flap) were noted in the short-time dilation group (43% vs. 14%; p=0.009), while significantly less reinterventions were performed following prolonged inflation, indicating that less severe dissections could be related with increased clinical patency.7 Additionally, this study demonstrated what was already known among vascular specialists—prolonged balloon inflation reduces the rate of severe dissections and consequently the rate of bailout

All rights reserved. Published by BIBA Publishing, London T:+44 (0)207736 8788, publishing@bibamedical.com. The opinions expressed in this supplement are solely those of Medtronic and the physicians and may not reflect the views of Vascular News.

stenting.

Recently, Shammas et al proposed a new intravascular ultrasound (IVUS)-based dissection classification system which combines the depth of injury from intima to adventitia and the circumference of dissection (the “iDissection” classification system).8 The same group used IVUS in order to investigate the morphology and incidence of dissections after femoropopliteal atherectomy and adjunctive angioplasty.

Outcomes highlighted two very interesting points. First, the concept of non-traumatic vessel preparation with atherectomy as to reduce dissections and therefore minimise bailout stenting should be reassessed with IVUS imaging. Second, this study points out that dissections are significantly underestimated by digital subtraction angiography. Specifically, dissections following atherectomy depicted by angiography were significantly less than those detected by IVUS (8 vs. 43, p<0.01; ratio, 5.75 to 1). Significantly more dissections were also detected

by IVUS following adjunctive angioplasty (39 vs. 11, p=<0.01; ratio, 3.55 to 1).9 The authors proposed that deeper vessel wall injuries not seen on angiography could be the cause of aggressive restenosis in apparently successful atherectomy procedures.

To conclude, severe arterial dissections following balloon angioplasty are more frequent than previously believed and seem to significantly affect outcomes.

In order to avoid severe dissections especially during endovascular treatment of

Stavros Spiliopoulos

hard, calcified lesions, several new balloon types have been proposed and are currently under investigation.10–12 Appropriate balloon type, accurate sizing and prolonged inflation seems to decrease the rate of severe dissections, enhance angioplasty outcomes and allow scaffoldfree endovascular treatment options.

References 1. Sharma SK, Israel DH, Kamean JL, et al. Clinical, angiographic, and procedural determinants of major and minor coronary dissection during angioplasty. Am Heart J. 1993; 126(1):39-47.

2. Castaneda-Zuniga WR, Formanek A, Tadavarthy M, et al. The mechanism of balloon angioplasty. Radiology. 1980; 135(3):565-71.

3. Bennett MR, O’Sullivan M. Mechanisms of angioplasty and stent restenosis: implications for design of rational therapy. Pharmacol Ther.

2001; 91(2):149-66.

4. Rogers JH, Lasala JM. Coronary artery dissection and perforation complicating percutaneous coronary intervention. J Invasive Cardiol. 2004; 16:493–499.

5. Fujihara M, Takahara M, Sasaki S, et al.

Angiographic Dissection Patterns and Patency Outcomes After Balloon Angioplasty for Superficial Femoral Artery Disease. J Endovasc Ther. 2017; 24(3):367-375.

6. Tepe G, Zeller T, Schnorr B, et al. Highgrade, non-flow-limiting dissections do not negatively impact long-term outcome after paclitaxel-coated balloon angioplasty: an additional analysis from the THUNDER study. J Endovasc Ther. 2013; 20:792-800.

7. Zorger N, Manke C, Lenhart M, Peripheral arterial balloon angioplasty: effect of short versus long balloon inflation times on the morphologic results. J Vasc Interv Radiol.

2002; 13(4):355-9.

8. Shammas NW, Torey JT, Shammas WJ, et al. Intravascular Ultrasound Assessment and Correlation With Angiographic Findings Demonstrating Femoropopliteal Arterial Dissections Post Atherectomy: Results From the iDissection Study. J Invasive Cardiol. 2018; 30(7):240-244.

9. Shammas NW, Torey JT, Shammas WJ. Dissections in Peripheral Vascular Interventions: A Proposed Classification Using Intravascular Ultrasound. J Invasive Cardiol. 2018; 30(4):145-146.

10. Díaz, J, Gómez-Menchero, A, Cardenal, R, Extremely High-Pressure Dilation with a New Noncompliant Balloon. Tex Heart Inst J. 2012; 39(5): 635–638.

11. Rigatelli, G, Palena, M, Cardaioli, P, et al.

Prolonged high-pressure balloon angioplasty of femoropopliteal lesions: Impact on stent implantation rate and mid-term outcome. J Geriatr Cardiol. 2014; 11(2): 126–130.

12. Graziani L. Low-Profile and Long Balloons.

What is the role of this technology in diabetic macroangiopathy and complex infrapopliteal interventions? Endovascular Today, May 2012.

By Konstantinos Stavroulakis St Franziskus Hospital Münster/University Hospital of Münster, Münster, Germany

Leaving nothing behind

Leave nothing behind in the femoropopliteal segment: is vessel preparation followed by drug-coated balloon the ultimate tool?

The introduction of drug-coated balloons (DCB) led to a paradigm shift in the endovascular therapy of femoropopliteal atherosclerotic disease. Numerous randomised controlled trials demonstrated a clear benefit of antiproliferative treatment over plain old balloon angioplasty (POBA) in terms of improved patency and reduced reintervention rates.1

I

nterestingly, despite the short-term transfer of paclitaxel in the vessel wall, DCB angioplasty is associated with a sustained clinical benefit over POBA up to four years.2 Thus paclitaxel coated balloons became the treatment of choice for de novo and re-stenotic TASC II A and B femoropopliteal lesions.3 Additionally, current recommendations suggest DCB angioplasty as an alternative treatment option to permanent scaffolding in the treatment of superficial femoral (SFA) and popliteal artery lesions up to 25cm.4 On the other hand, the complexity of the target lesion may negatively affect the outcomes of DCB angioplasty. Similar to standard balloon catheters, DCBs are associated with an increased risk for flow-limiting dissections

and bailout stent deployment. Furthermore, the calcium burden might lead to suboptimal vessel expansion and inhibits the transfer of paclitaxel in the adventitial layer explaining inferior outcomes of DCBs in severely calcified lesions.5-7 Vessel preparation has the goal of preparing the vessel with maximum lumen gain while minimising dissection and vessel trauma overall without the need of a permanent scaffold.

Vessel preparation prior to the application of the antiproliferative agent might potentially, improve the results of DCBs and extend the use of “leave nothing behind” strategies in more challenging lesions.

Among many different vessel preparation technologies there are two concepts gaining consensus among interventionalists: atherectomy and advanced dilatation technologies. These tools propose alternative ways to achieve revascularisation.

Plaque debulking

Among several debulking technologies, the concept of plaque excision with directional atherectomy prior to anti-restenotic therapy (DAART) 1a: Initial angiogram has shown favourable

1b: Treatment with directional atherectomy (Hawk One) and DCB angioplasty

Konstantinos Stavroulakis

outcomes in calcified, restenotic and long lesions as well as in anatomical areas exposed in high mechanical stress.8-11 In the Directional Atherectomy Followed by a Paclitaxel-Coated Balloon to Inhibit Restenosis and Maintain Vessel Patency (DEFINITIVE AR) trial, DAART suggested trends to higher patency rates compared to DCB angioplasty alone (82.4% vs. 71.8%, respectively). Nonetheless, this study was not powered to show significant differences between the two modalities. Lesion calcification and lesion length >10cm were identified as potential predictors for superior outcomes after DAART.8 In our single centre analysis, combination therapy showed higher 12 months patency- and reduced reintervention rates than DCB angioplasty alone for isolated popliteal artery disease.9 Finally, in a further retrospective study preparation of the atherosclerotic common femoral artery with directional atherectomy prior to paclitaxel application led to higher primary patency than DCB angioplasty, but

1c: Final result

3

The future of angioplasty

the difference was not statistically significant.10 Sufficient vessel preparation might additionally reduce the rates of flow-limiting dissections and consequently the need for a permanent scaffold. In the DEFINITVE AR trial DAART led to a significant reduction of dissections (19% for DCB and 2% for DA+DCB [p=0.01]), while reduced bailout stenting and dissection rates were observed in our published experience for popliteal and common femoral atherosclerotic disease.8-10 This finding could be particularly meaningful in the treatment of “nostenting zones” like the common femoral and the popliteal artery or anastomotic bypass graft stenosis.

Controlled dilatation

In this context, angioplasty with a nitinol constrained balloon catheter might serve as an alternative vessel preparation option in non-severe calcified lesions. The Chocolate catheter

is characterised from a mounted nitinol constraining structure, which is designed to facilitate a modulated dilatation and creation of small balloon segments (‘‘pillows’’ and “grooves”). The unique structure of the catheter minimises the elongation of the balloon during inflation and enables a “smooth” angioplasty, which reduces the radial force exerted on the arterial wall, the risk of post-angioplasty inflammation and flow-limiting dissection. In the CHOCOLATE BAR study, the authors reported a 0% core lab adjudicated flow-limiting dissection rate and 1.6% bailout stent rate in patients with severe claudication and femoropopliteal disease, suggesting a potential role for this technology in preparing the vessel prior to DCB angioplasty.

Despite the lack of consensus regarding the reporting standards of “leave nothing behind” studies, and the fact that no definitive conclusions can yet be drawn, the

current body of evidence suggests an added benefit from vessel preparation in calcified lesions as well as in anatomical areas where stent deployment should be avoided—such as, the popliteal, the common femoral and the distal superficial femoral artery.

Preparation of the vessel wall can significantly reduce the need for permanent scaffolding and improve the outcomes of “leave nothing behind” in challenging lesions.

References: 1. Katsanos K, Spiliopoulos S, Paraskevopoulos I et al. Systematic Review and Meta-analysis of Randomized Controlled Trials of Paclitaxel-Coated Balloon Angioplasty in the Femoropopliteal Arteries: Role of Paclitaxel Dose and Bioavailability.

J Endovasc Ther. 2016;23(2):356-70.

2. Schneider P. 4-year outcomes from the IN.PACT SFA trial. Presented at VIVA 2017 3. Cortese B, Granada JF, Scheller B et al.

Drug-coated balloon treatment for lower extremity vascular disease intervention: an international positioning document. Eur Heart J. 2016;37(14):1096-103.

4. Aboyans V, Ricko JB, Bartelink MEL et al. 2017 ESC Guidelines on the Diagnosis and Treatment of Peripheral Arterial Diseases, in collaboration with the European Society for Vascular Surgery (ESVS): Document covering atherosclerotic disease of extracranial carotid and vertebral, mes-

enteric, renal, upper and lower extremity arteries.

Eur Heart J. 2018;39(9):763-816.

5. Tepe G. IN.PACT global drug-coated balloon for complete total occlusion. Presented at Charing Cross International Symposium 2016.

6. Tepe G, Beschorner U, Ruether C et al. DrugEluting Balloon Therapy for Femoropopliteal Occlusive Disease: Predictors of Outcome With a Special Emphasis on Calcium. J Endovasc Ther.

2015;22(5):727-33.

7. Fanelli F, Cannavale A, Gazzetti M, et al.

Calcium Burden Assessment and Impact on DrugEluting Balloons in Peripheral Arterial Disease.

Cardiovasc Intervent Radiol. 2014;37(4):898-907 8. Zeller T, Langhoff R, Rocha-Singh KJ, et al; DEFINITIVE AR Investigators. Directional atherectomy followed by a paclitaxel-coated balloon to inhibit restenosis and maintain vessel patency: twelve-month results of the DEFINITIVE AR study. Circ Cardiovasc Interv.

2017;10:e004848.

9. Stavroulakis K, Schwindt A, Torsello G, et al. Directional atherectomy with antirestenotic therapy vs drug-coated balloon angioplasty alone for isolated popliteal artery lesions. J Endovasc Ther. 2017;24:181-188.

10. Stavroulakis K, Schwindt A, Torsello G et al. Directional atherectomy with antirestenotic therapy vs drug-coated balloon angioplasty alone for common femoral artery atherosclerotic disease. J Endovasc Ther. 2018;25(1):92-99.

11. Cioppa A, Stabile E, Popusoi G, et al.

Combined treatment of heavy calcified femoropopliteal lesions using directional atherectomy and a paclitaxel coated balloon: one-year single centre clinical results. Cardiovasc Revasc Med. 2012;13:219–223.

12. Stavroulakis K, Bisdas T, Beropoulis E. Endovascular Treatment of a Severe Calcified Popliteal Artery Lesion by Endovascular Lithoplasty and Drug-Coated Balloon Angioplasty in a Patient With Critical Limb Ischemia and Chronic Kidney Disease. Vascular Disease Management 2018;15(6):E53-E55.

13. Mustapha et al. Catheter Cardiovasc Interv.

2018;1–5.

Is POBA dead? New concepts towards Angioplasty 2.0

By Gaston Schütz Medical Director of Hôpitaux Robert Schuman, Luxembourg

Over 50 years ago, Dr Charles Dotter performed the first angioplasty in the leg by passing progressively larger catheters through narrowed arteries. A ‘real’ balloon catheter for opening the iliac artery was developed in 1973 by Dr Werner Porstmann; Dr Andreas Gruentzig then performed the first balloon angioplasty of a coronary artery.

T

hese developments and interventions were the beginning of interventional medicine and an incredible journey in developing new and better devices to treat our patients.

Despite its merits, plain old balloon angioplasty (POBA) is often associated with suboptimal outcomes due to complications following balloon inflation related to vessel trauma and flow-limiting dissections that may require bail out stenting. The technique of balloon inflation during angioplasty is extremely important to the final result as underinflation can lead to elastic recoil, while over inflation can lead to neointimal hyperplasia, either of which could result in restenosis. The importance of vessel preparation prior to drug delivery has focused our attention on understanding how a regular angioplasty balloon behaves in a vessel.

Blood Vessel

Plaque

Shear Stress Formation

A standard balloon unfolds from its wrapped state with inflation, resulting in the application of force in a nonuniform manner to the stenotic lesion. Uncontrolled expansion with the standard angioplasty balloon results in increased torsional (Figure 1), longitudinal (Figure 2), and radial (Figure 3) stresses that can strain the vessel wall and lead to increased incidence of dissection and elastic recoil.

These restrictions of the POBA technique, which already includes the word ‘old’, has led to the development of a new kind of angioplasty balloon that address many of the limitations of the ‘classic’ balloons. The Chocolate PTA balloon was thus specifically designed to address the challenges of plain old balloon angioplasty.

Chocolate is constrained by a nitinol cage that limits balloon torsion and elongation Dissection Blood Vessel

Plaque Plaque

Folded Balloon PRE-INFLATION

Partially Inflated Balloon DURING INFLATION

Figure 1

4

during inflation. The nitinol cage sub-segments the balloon when inflated, creating pillows and grooves on the balloon Gaston Schütz surface that increase the balloon contact surface area (Figure 4). The intent of this balloon design is to disperse the force associated with angioplasty along this increased contact surface resulting in a controlled and differential dilatation approach to minimise overall vessel trauma. It is important to underline that the nitinol cage does not

Inflated Balloon

Stress Formation/ Dissection

Plaque

Folded Balloon

Partially Inflated Balloon PRE-INFLATION

Plaque

Longitudinal Stress

Stress Formation/ Dissection

Longitudinal Stress

DURING INFLATION

END OF INFLATION

Figure 2

Blood Vessel

Plaque

Plaque

design and comes in 0.014- and 0.018-inch guidewires. It is available in sizes to treat both above- and below-the-knee lesions with balloon diameters of 2.5–6mm, balloon lengths of 40–120mm, and 120–150cm RadialStress Formation

Partially Inflated Balloon

Folded Balloon PRE-INFLATION

Plaque

DURING INFLATION

catheter lengths.

of the treated vessel segment.

The Chocolate balloon addresses the shortcomings of traditional angioplasty balloons. Its unique design minimises unwanted torsion, elongation and stretching

The rates and gravity of dissections can be reduced significantly, lowering the need for bailout stenting and potentially leading to better clinical outcomes.

Dissection

Pressure Relief Grooves

Uniform Dilation Pillows

Chocolate PTA Balloon evidence

score nor cut the vessel wall, on the contrary, it is designed to minimise overall stress transmitted to the vessel wall with the goal of minimising dissection while maximising vessel gain.

Chocolate has an over-the-wire

Inflated Balloon END OF INFLATION

Figure 3

Nitinol Constraining Structure

Figure 4

Chocolate PTA Balloon: is there any evidence?

By Francesco Speziale Full Professor of Vascular Surgery, Chief Vascular and Endovascular Surgery Unit, Department of Surgery “Paride Stefanini”, “Sapienza” University of Rome, Italy Percutaneous transluminal angioplasty (PTA) has become the first-choice treatment for most patients. Unfortunately, simple PTA, even using drug-coated balloons (DCB), could be associated with acute complications following inflation and deflation of standard balloons. These complications are related to vessel trauma resulting in flow-limiting dissections or in unsatisfactory angioplasty results often requiring bailout stenting in up to 40% of cases.

D

espite the fact that randomised trials have demonstrated early patency rates with stents superior to those observed with PTA alone, long-term results are still affected by a non-negligible rate of complications. All of the above are compelling physicians to avoid stenting whenever feasible, instead adopting a new strategy consisting of proper vessel preparation with PTA or plaque debulking devices before drug delivery

by DCBs. Among the solutions proposed, promising results were reported using the Chocolate PTA Balloon Catheter (Medtronic) in the “Chocolate BAR Registry” (Mustapha et al. Catheter Cardiovasc Interv. 2018;1–5). The authors treated femoropopliteal lesions at 30 US centres between 2012 and 2014, and they reported a procedural success rate of 85.1%, and a freedom from stenting of 93.1%, without flow-limiting dissections.

Here I report my centre’s experience treating intermittent claudication patients using the Chocolate PTA Balloon, a ‘‘nitinol-constrained’’ balloon for vessel preparation before routine DCBs in a standardised protocol.

Consecutive intermittent claudication patients presenting with femoropopliteal lesions were treated by a standardised protocol consisting of: PTA using the Chocolate PTA Balloon Catheter, followed by drug-coated balloon and bailout stenting with drug-eluting stents, if required.

In cases of stenosis, target lesions were crossed by a 0.035-inch hydrophilic guidewire, thereafter changed to a 0.018-inch guidewire. Subsequently, PTA with nitinol-constrained balloons (nominal

pressure for at least three minutes) was performed and followed by DCB. In cases of chronic total occlusions (CTOs), first, intraluminal recanalisation attempts were performed.

After successful recanalisation, both intraluminally or subintimally, the guidewires were changed to a 0.018-inch one and PTAs with nitinol-constrained balloon plus DCB were executed. Bailout stenting was performed in cases of haemodynamically significant residual stenoses, or flow-limiting dissections.

One hundred and sixty-eight limbs were treated in intermittent claudication patients presenting at Rutherford Category 3, 156 procedures were performed for de novo lesions, one for poststenting occlusion, and 11 for post-PTA vessel re-occlusion. Fifty-eight limbs (34.5%) presented with severe stenosis with an average lesion length of 65.8±31mm. The rates of CTOs were 65.5%, and the average occlusion length was 187.26±73mm; in 36 limbs, CTO was >150mm.

Successful recanalisation was achieved in 162 lesions, while in six cases several recanalisation attempts were conducted without success. After recanalisation, in all patients, nitinol-constrained balloon PTA followed by DCB was performed by protocol. The bailout stenting rate was 9.8% (16/162).

All patients completed 30-day clinical and laboratory assessments: primary patency and freedom from target lesion revascularisation were 100%, and 122 patients were completely asymptomatic for intermittent claudication. Ankle Brachial Index (ABI) for the entire cohort was 0.98±0.007.

Francesco Speziale

Clinical improvement (two or more Rutherford categories) was evident in 98.8% of cases.

Clinical and laboratory assessments (ABI and duplex ultrasound) were obtained in all treated limbs at three months (ABI mean ± SD: 0.97±0.007), in 96 at 12 months (ABI 0.92±0.02), and in 32 at 24 months (ABI 0.67±0.16). At three-month follow-up, four patients presented with target lesion re-occlusion and two with severe restenosis. At 12-month follow-up, 56% of patients were completely asymptomatic (Rutherford category 0), with an improvement of two or more Rutherford categories in 85.4% of patients. ABIs measured at 12 months were significantly higher with respect to preoperative values: 0.51 versus 0.92; p<0.001. Overall primary patency was 98.8%, assisted patency and secondary patency were 98.8%, and freedom from target lesion revascularisation was 97.6%. No differences in outcomes were recorded between patients presenting with stenosis and/or CTOs with a primary patency of 96.5% and 96.4%, respectively (p=0725).

On the basis of my experience, I could suggest the use of the Chocolate PTA Balloon as standard vessel preparation technique in all patients presenting with intermittent claudication due to femoropopliteal lesions.

5

Real-world experience

Chocolate PTA balloon: real-world experience Vascular News speaks to Dr Lorenzo Salute (Casa di Cura Pierangeli, Pescara, Italy), Dr Gaston Schütz (Hôpitaux Robert Schuman, Luxembourg) and Professor Francesco Speziale (“La Sapienza” University of Rome, Italy) about their personal experience with the Chocolate Balloon Catheter, how it has changed their practice and how it fits into their workflow.

What do you think the consequences of dissection are when treating femoropopliteal lesions?

Salute: Intimal dissection is a

physiological mechanism of PTA that involves the various arterial layers and detaching the intima from the media produces a dissection. What is important is that the dissection is not extensive and is not limiting the flow in any way, otherwise the physiological turns into pathological mechanism and the result of the PTA is not optimal and can lead to early restenosis or acute obstructions.

Schütz: Dissections, when they appear, always pose a decisional dilemma. On the one hand, being among the believers in the ‘leave nothing behind’ movement, I like to avoid stenting with non-resorbable materials whenever possible.

However, bailout stenting is still too commonly required in order to overcome flow-limiting dissections while using ‘conventional’ balloons.

New techniques, which can potentially lower the stenting rates, come more and more into focus in order to be able to avoid putting metal in our patients.

Speziale: When treating superficial femoral artery and popliteal lesions, especially in claudicant patients, the evidence of a post PTA flow-limiting dissection represents one of the worst complications for vascular surgeons. That is because PTA resulting in a flow-limiting dissection mandatorily requires aggressive management by stent implantation to achieve a satisfactory procedural result. All of the above, in my personal opinion, results in a major concern because stent implantation (despite better results in the very early period, in respect to simple PTA) results, by itself, in a severe risk factor for restenosis, re-occlusions, fractures, pseudoaneurysm development, and the need for reinterventions.

How has your practice changed since you started using the Chocolate PTA balloon?

Salute: In fact, I have not changed the approach to treatment that was already in place before primary PTA. In case of steno-obstructive

6

Lorenzo Salute

Gaston Schütz

Francesco Speziale

lesions <10cm, in particular in the femoropopliteal or popliteal passage, I currently use Chocolate because—in light of the experience gained—I expect a minimal or no dissection. Stenting, then, is relegated to the rare and more complex bailout cases.

Schütz: The Chocolate PTA balloon has indeed rapidly changed our daily practice. Using this balloon on a regular basis for preparing the vessels before delivering the drug via a drug-coated ‘regular’ balloon has lowered our stent usage rates significantly. We still see dissections when using the Chocolate balloon, but they generally tend to be more localised and less flow limiting than the ones we saw doing vessel preparation with a regular PTA balloon.

Speziale: Honestly, my personal practice didn’t change significantly after I started to use Chocolate PTA Balloon Catheter. I was convinced, and still I am, that the endovascular approach should represent the first-line treatment for all claudicant patients presenting superficial femoral artery and popliteal diseases.

The major change (I would say the “revolution”) was represented by the drop in the bailout stenting rate.

Changing nothing except the use of the Chocolate PTA Balloon Catheter instead of a standard balloon for the first angioplasty, resulted in a dramatic decrease in bailout stenting—from 30% to less than 10%.

Now, the “leave nothing behind” concept is more than a dream in my experience: it is real!

treatment avoiding a double PTA as Chocolate is no longer than 12cm. I do not distinguish particular traits as it relates to the patient. Regarding the lesion, instead, I avoid treatment with Chocolate in lesions with strong calcific component, preferring to use non-compliant balloons in these cases.

Schütz: We use this device in all kinds of lesions (stenosis, occlusions, restenosis, calcified and noncalcified lesions, in-stent stenosis).

The device tracks well, inflation and deflation times are excellent, the pushability of the device is very good due to the braided shaft, and, astonishingly, the friction of the balloon, which is anticipated to be significant due to the nitinol cage at its surface, is quite acceptable.

Speziale: During the first months of our learning curve, my collaborators and I performed a kind of selection prior to using the Chocolate PTA Balloon Catheter. Initially, Chocolate was preferentially adopted in short TASC A/B lesions. The excellent results we have obtained have pushed us to do something more. At the current time, the Chocolate Balloon is routinely used as first-line therapy in all femoropopliteal lesions, regardless of TASC classification and lesion length. Moreover, Chocolate is also used to treat restenosis and reocclusion in the non-stented arterial segment. Some concerns still exist about the possibility of performing Chocolate Balloon PTA in in-stent restenosis or re-occlusion, because it is theoretically possible that the nitinol constraining structure of the balloon could entrap the stent’s struts during deflation.

guarantees the right stability.

I avoid pre-dilation which could affect the final result.

I normally choose a size appropriate to the calibre of the non-plaque points of the vessel (5 is the most widely used size on the femoropopliteal axis).

I use the balloon at low pressure (about 4atm) for about 20 seconds and then push at nominal pressure for at least three minutes.

Schütz: Using a Chocolate balloon is no different to using a regular PTA balloon. We try not to oversize in regard to the inner vessel lumen. On-table measurements of the pre-treatment angio proximal and distal to the lesion(s) give you a good reference for sizing. Inflation should be done gently, and usually the nominal pressure should be enough to get the job done. Up to now, we have not seen a balloon rupture. We carefully avoid going up to the RBP as potentially, a rupture of a Chocolate balloon in a vessel can be much worse than such an event in a normal balloon as the metal cage confines the rupture site to a small area, thus increasing the pressure of the outflowing liquid.

Speziale: The Chocolate PTA Balloon Catheter is a novel concept of angioplasty balloon and, thanks to its peculiar nitinol constraining structure, it promises unique performances. The Chocolate balloon is characterised by a mounted nitinol constraining structure, allowing uniform inflation and rapid deflation. The attributes of the nitinolconstrained balloon are designed for modulated dilatation and creation of small balloon segments (so-called ‘‘pillows’’), intended to minimise balloon elongation during angioplasty and radial stress on arterial walls, reducing vessel damage.

Despite those considerations, the Chocolate Balloon is a balloon. So, I have no particular technical tips to underline. I could suggest choosing

In which patients or for which lesions are you primarily using the Chocolate PTA balloon catheter?

Salute: I use Chocolate in

steno-obstructive lesions <10cm.

In an obstruction >15cm, I currently prefer to use a long balloon to obtain better uniformity of the

What are your technical tips for using the Chocolate PTA balloon?

Salute:

I use a 6F introducer sheath (or a 5F Destination) that—used in cross—accepts all the sizes and

How does Chocolate currently fit into your personal treatment algorithm?

Salute: The Chocolate PTA bal-

loon is currently the first choice in all cases in which plaque involves the femoropopliteal and popliteal segments, taking into account the patient’s age and leg runoff.

Schütz: The Chocolate PTA balloon has become our workhorse for vessel preparation before delivering drug to the vessel wall.

To us, the Chocolate balloon is the

vessel preparation device, and the drug-coated balloon (DCB) is the drug delivering device. Ideally, the DCB just delivers the drug without doing any (additional) harm to the prepared vessel. At present, we believe that using the Chocolate balloon creates less damage to the vessel during inflation than a regular PTA balloon, thus enabling us to have less need for bailout stenting. Potentially and hopefully, creating less ‘collateral’ damage to a vessel while recreating its lumen will translate in better patient outcomes.

Speziale: Nowadays, I have a simple and well codified treatment algorithm for all claudicant patients with femoropopliteal occlusive disease. Once the patient is scheduled for an endovascular procedure, the same standardised approach is used in my centre by myself and my collaborators: Contralateral femoral access; Intraluminal recanalisation, whenever possible; Chocolate PTA Balloon Catheter dilatation;

Drug-coated balloon angioplasty; Eventually, bailout stenting (always by a drug-eluting stent).

Can you describe a memorable case using the Chocolate PTA balloon?

Salute: My most memorable case using the Chocolate PTA balloon was an 88-year-old female patient with severe claudication <100m (type 2B). Pre-procedure angiography showed a short occlusion of about 3cm at in the distal portion of the left SFA. I used a 6F x 45cm introducer sheath in the presence of aortic and calcific aortic Carrefour. The lesion was crossed with a 0.018 inch guidewire. The lesion was crossed directly with a 5x40 Chocolate PTA balloon and an inflation of two minutes to 8–9 bars was applied. The post-procedure angiogram showed a new and totally satisfying angiographic result.

Schütz: The patient presented with 60% stenosis of the lower popliteal artery. The treatment included crossing with an 0.018 wire

and placement of a 5mm Chocolate balloon under Roadmap imaging.

Vessel preparation was done with an inflated Chocolate balloon, and the delivering device was a 5mm drug-coated balloon. I observed an excellent angiographic result without stenting.

Speziale: Of course, I can: I remember a lot of cases! Although the first case I did occupies a special place in my memory, today I prefer to talk of another one.

It was the case of a 76-year-old gentleman presenting with severe claudication with a free walking distance interval of less than 50 metres, due to a long, severely calcified femoropopliteal total occlusion. Despite the fact that the patient presented with a 25cm occlusion which extended to the P2 portion of the popliteal artery, multiple Chocolate PTA Balloon Catheter dilatation provided an excellent immediate result (case image). At two-years follow-up, treated arteries are still patent and the patient presents with complete symptoms relief.

Pre-procedure

C

Real-world experience

a 1:1 ratio to reference vessel diameter, as evaluated on preoperative imaging, and in cases of long lesions requiring more than one balloon, to adopt an overlap area of at least 10mm. The balloon should be inflated not exceeding nominal pressure and angioplasty continued for a long time (at least three minutes). As I mentioned before, a word of caution should be made when using the Chocolate Balloon Catheter in a previously stented arterial segment.

Post-procedure

D

E E F A B Dr Schütz’s case: (A) 60% Stenosis of the lower popliteal artery (B) Crossing with an 0.018 wire and placement of a 5mm Chocolate Balloon under Roadmap imaging (C) Advancing the device for vessel preparation with a 5mm Chocolate Balloon (D) Inflated Chocolate Balloon (E) 5mm drugcoated balloon as drug delivering device (F) Excellent angiographic result without stenting

B

A Dr Salute’s case: (A) Baseline (B) Dilatation with Chocolate 5x40 (C) Final result

C

Dr Speziale’s case: Pre-procedure diagnostic angiography (from top to bottom) showing flush SFA occlusion, severe calcification and distal run-off. Post-procedure completion angiography, after Chocolate balloon angioplasty, with good SFA patency in absence of flow-limiting dissection.

7