Clinical Overview of the Jetstream Atherectomy System

ABSTRACT: There has been significant interest in percutaneous atherectomy as a technique for treating peripheral arterial disease (PAD). Relatively recently, the Jetstream Atherectomy System was approved for use in the United States. This device is unique as it incorporates an aspiration component. This manuscript includes a description of the device, its method of use, and a summary of the available clinical data regarding its use in the lower extremities. 

VASCULAR DISEASE MANAGEMENT 2013:10(10):E212-E215

Key words: atherectomy, peripheral arterial disease, claudication

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While bypass surgery may still be considered the standard for peripheral revascularization, the requirement for anesthesia, the relatively high incidence of morbidity, and the significant time required for postoperative recovery remain a concern. Consequently, there has been growing interest in new technologies for the percutaneous revascularization of peripheral arterial disease (PAD) in patients with chronic limb ischemia and symptoms refractory to conservative medical treatment.  

In order to improve on the short- and long-term results of standard balloon angioplasty (PTA), several forms of atherectomy have been recently applied to peripheral revascularization. Our group was privileged to perform a first-in-man feasibility study in 2004 using a prototype Pathway Medical Technologies aspiration and atherectomy device for the treatment of femoral-popliteal and infrapopliteal disease. Since that time the device has gone through several iterations, dramatic refinement, and extensive clinical evaluation culminating in widespread commercial availability. A description of the device and brief summary of its clinical utility follow.  

Device Description

The Jetstream system (Bayer HealthCare) consists of two main components: (1) a nonsterile console which contains an electric motor and two peristaltic pumps (for saline infusion and blood/saline aspiration) which is mounted on an IV pole and (2) a control “pod” which is used by the operator for device activation (Figure 1). The console is attached to a standard electric power source and is reusable. The control pod is a sterile single-use component.

The current Jetstream expandable cutter (XC) catheters achieve graded atherectomy using two sets of rotating stainless steel blades. One set of blades sits within a fenestrated metal housing at the tip of the catheter. This set will affect cutting in a diameter of just over 3 mm when rotated clockwise. The second set of five blades are hinged and mounted just proximal to the distal housing. These blades will affect cutting in a diameter of 3 mm when rotated counterclockwise (Figure 2). Both sets are powered by an electric motor that spins them at 60 krpm to 70 krpm.  

The Jetstream single-cutter (SC) catheters designed for subpopliteal use. The SC devices are available in 1.6 mm and 1.85 mm sizes for use in vessels with a reference diameter of 2.0 mm to 3.0 mm.  The working shaft is also longer allowing the catheter to reach infrapopliteal disease. Both the XC and SC devices use the principal of differential cutting in which fibrous and calcified tissue/plaque is preferentially cut in favor of more compliant normal tissue.

All Jetstream devices must be used through a 7 Fr diameter sheath and are designed for use with 0.014” diameter, 300-cm-long guidewires. The Jetwire is a proprietary wire available through Bayer HealthCare. It should be noted that hydrophilic-coated wires are not recommended. During device activation, saline is infused through the distal tip of the catheter and aspirated at a similar rate in order to help prevent dissection and potentially retrieve small embolic material into a collection bag. Saline infusion and aspiration rates depend on both the catheter size and the blades down or up condition.  Variables that increase these rates are catheter size and the blade down condition. The large catheter has a maximum infusion rate of 43 mm/min and aspiration rate of 51 mm/min with the blades down. Although there is no formal data, many operators add
vasodilators and heparin to the infusate. In our lab we add 2,000 units of heparin, 5 mg of verapamil, and 1 mg of nitroglycerin to each liter of normal saline infusate.

Instructions for use state that the Jetstream G3 or Navitus device is intended for use in atherectomy of the peripheral vasculature and to break apart and remove thrombus from upper and lower extremity peripheral arteries ≥3 mm in diameter. It is not intended for coronary, carotid, iliac, or renal vasculature. Use of this device in the subintimal (or potentially subintimal) space should be avoided in order to reduce the chance of perforation.  

When advancing the device a “pecking” motion is recommended whereby the tip of the catheter is repeatedly advanced into the lesion with gentle pressure and then withdrawn. This allows for the infusate to infiltrate the lesion area and also prevents excessive aspiration/suction with tissue collapse around the catheter. This can result in intimal dissection and device stalling. When removing the device a reverse function is used on the control pod that causes aspiration alone without any blade action.

Clinical Data

In a seminal study designed to support regulatory approval, Zeller et al reported on a series of 210 lesions treated in 172 patients between 2006 and 2007 with the earlier pre-G2 iteration of the device. The patients were relatively complex with a high prevalence of diabetes (47%), hypertension (93.6%), renal disease (15.75%), prior lower extremity revascularization (51.2%) and documented coronary disease (16.9%). Maximum lesion lengths were ≤10 cm and ≤3 cm for femoral/popliteal and infrapopliteal lesions respectively. Fifty-one percent of lesions were moderately to heavily calcified and 31% of lesions were total occlusions. While thrombotic lesions were included, in-stent restenosis lesions were excluded. The lesion crossing and debulking success rate was 99% with a mean device activation time of 3.5 minutes. Only 7% of lesions were stented. Minor embolic events were noted in 10% of cases and 4 perforations (2%) occurred. At 6 months major adverse events had occurred in 19% of patients. Most of these events were target lesion revascularizations (TLR), which occurred in 15% and 26% of patients at 6 and 12 months respectively.¹

The results for diabetic (n=80) and nondiabetic patients (n=92) in this study were compared. Other than higher weight in the diabetic cohort there were no significant differences in baseline clinical parameters between groups. Lesion-specific variables were also similar. Other than a higher incidence of embolic events noted in the diabetic group (13.8% vs 6.5%; P<.001), acute procedural outcomes were similar. At 12 months major adverse event rate (death, myocardial infarction, amputation, TLR, target vessel revascularization) was 25% for diabetics and 31.5% for nondiabetics (P=NS). Most events were related to TLR, which occurred in 20% and 28% of the diabetic and non-diabetic groups (P =NS).²

Use of this device in moderate and severely femoral/popliteal calcified lesions was examined by intravascular ultrasound (IVUS) in a small (n=26) single-center study. Baseline mean lesion length was 55 mm and diameter stenosis 82% with a calcium arc of ≥90°. The primary endpoint of the study was calcium removal and lumen gain as measured by IVUS. Lumen area significantly increased from 6.6 mm² to 9.8 mm² (P<.0001). Although there was not a significant decrease in the calcium arc following atherectomy, the maximum arc of calcium reverberations increased significantly (21° to 69°; P=.0006) and the convexity of the surface shape of the calcium decreased significantly (67% to 26%; P=.0004). The authors concluded that calcium modification contributed to the increase in lumen size. Importantly, there were no major adverse events reported at 30 days.³

Although a potential concern, clinically apparent hemolysis does not appear to be a frequent occurrence with Jetstream atherectomy. There is a single clinical report describing hemoglobinuria, elevated lactate dehydrogenase, low haptoglobin, and a decrease in serum hemoglobin (12.1 to 10.8 g/dL) occurring after a cumulative 11.7 minutes of device activation. The patient was observed overnight without any clinical deterioration. The urine cleared and there was no further drop in hemoglobin.⁴ 

A more relevant concern is the incidence and clinical importance of embolization related to device use. Boiangui et al examined particulate debris retrieved with an embolic protection device (Emboshield, Abbott Vascular) following Jetstream atherectomy in 22 patients with SFA disease (>70% stenosis, mean lesion length 120 mm). Macroscopic debris was retrieved in 95.4 % (n=21) patients with clinically significant emboli, defined as ≥2 mm in its longest axis, was recovered in 72.4% (n=16) of patients.⁵ Shrikande et al used prospective registry data to examine the incidence of embolization occurring in the treatment of 2,137 lesions (1,029 patients) undergoing atherectomy with four different atherectomy devices.⁶ Angiographic review of pre and post device run-off angiograms was performed. The overall rate of embolization was 1.6%. Higher rates of embolization were associated not only with more complex lesions such as in-stent stenotic lesions and chronic total occlusions compared to de-novo lesions and (3.2% vs 2.4% vs 0.9%; P=.01) but also with device type. The incidence of angiographically apparent emboli was 22% for Jetstream and 22% for Diamondback (Cardiovascular Systems, Inc.) compared to 1.9% for Silverhawk (Covidien) and 3.6% for laser (Spectranetics). It must be noted however that far fewer cases were performed with the former two devices compared to the latter (n=36 vs n=791), possibly indicating an operator effect. Importantly, these embolic events are, in general, successfully managed using endovascular techniques, as has been described.⁷

Further information regarding the clinical safety and efficacy of this device will be available following completion of the industry-sponsored JET registry (n=500) whose primary endpoint is 12-month binary restenosis determined by duplex ultrasound. Smaller studies investigating its utility in specific lesion subsets such as in-stent restenosis and calcified are also ongoing.   

Conclusion

Although published data are limited, the Jetstream atherectomy device appears to be safe and has a high rate of acute success providing acceptable mid- and long-term arterial patency rates. The use of embolization protection may be beneficial when using this device. 

Editor’s Note: Disclosure:  The author has completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The author reports honoraria from Medtronic and AstraZeneca.  

 Manuscript received August 26, 2013; provisional acceptance given September 9, 2013; final version accepted September 11, 2013.  

Address for correspondence: Ronald P. Caputo, MD, SJH Cardiology Associates, 4820 W Taft Rd, Liverpool NY, 13088,  United States. Email: caputo331@msn.com

References  

1. Zeller T, Krankenberg H, Steinkamp H, et al. One-year outcome of percutaneous rotational atherectomy with aspiration in infrainguinal peripheral arterial occlusive disease: the multicenter Pathway PVD trial. J Endovasc Ther. 2009;16(6):653-662.
2. Sixt S, Scheinert D, Rastan A, et al. Rotational and aspiration atherectomy in infrainguinal arteries in patient with and without type 2 diabetes mellitus. Ann Vasc Surg. 2011;25(4):520-529.
3. Maehara A, Mintz GS, Shimshak T, et al. Jetstream atherectomy can remove superficial calcium in severely calcified peripheral arteries. Poster presented at: ISET 2013; Miami, FL. https://www.eventscribe.com/2013/posters/isetcio/SplitViewer.asp?PID=MTEwNTg2MjU2#
4. Korabathina R, Staniloae CS. Intravascular hemolysis following peripheral atherectomy with the pathway Jetstream catheter. Vasc Dis Manag. 2010;7(4):110-111.
5. Boiangiu C, Fissha M, Kaid K, et al. Analysis of retrieved particulate debris after superficial femoral artery (SFA) atherectomy using the Pathway Jetstream G3 device. Paper presented at: SCAI 2011 Scientific Sessions; Baltimore, Maryland.
6. Shrikhande GV, Khan SZ, Hussain HG, Dayal R, McKinsey JF, Morrissey N. Lesion types and device characteristics that predict distal embolization during percutaneous lower extremity interventions. J Vasc Surg. 2011;53(2):347-352. 
7. Reeves R, Imsais JK, Prasad A. Successful management of lower extremity distal embolization following percutaneous atherectomy with the JetStream G3 device. J Invasive Cardiol. 2012;24(6):E124-E128.