A novel drug-coated scoring balloon for the treatment of coronary in-stent restenosis: Results from the multi-center randomized controlled PATENT-C first in human trial.

BACKGROUND: Scoring balloons produce excellent acute results in the treatment of in-stent restenosis (ISR), fibro-calcific and bifurcation lesions but have not been shown to affect the restenosis rate. A novel paclitaxel-coated scoring balloon (SB) was developed and tested to overcome this limitation. METHODS AND RESULTS: SB were coated with paclitaxel admixed with a specific excipient. Patients at four clinical sites in Germany and one in Brazil with ISR of coronary bare metal stent (BMS) were randomized 1:1 to treatment with either a drug-coated or uncoated SB. Baseline and 6-month follow-up quantitative coronary angiography was performed by an independent blinded core lab and all patients will be evaluated clinically for up to one year. The primary endpoint was angiographic in-segment late lumen loss (LLL). Secondary endpoints included the rate of clinically driven target lesion revascularization (TLR), composite of major adverse cardiovascular events (MACE), stent thrombosis and other variables. Sixty-one patients were randomized (28 uncoated and 33 drug-coated SB); mean age 65 years, males 72%, and presence of diabetes 39%. At 6-month angiography, in-segment LLL was 0.48 ± 0.51 mm in the uncoated SB group versus 0.17 ± 0.40 mm in the drug-coated SB group (P = 0.01; ITT analysis). The rate of binary restenosis was 41% in the uncoated SB group versus 7% in the drug-coated SB group (P = 0.004). The MACE rate was 32% with the uncoated SB vs. 6% in the drug-coated SB group (P = 0.016). This difference was primarily due to the reduced need for clinically driven TLR in the coated SB group (3% vs. 32% P = 0.004). CONCLUSIONS: A novel paclitaxel-coated coronary SB has been developed and successfully used in a first-in-human randomized controlled trial [ClinicalTrials.gov Identifier: NCT01495533]. © 2015 Wiley Periodicals, Inc.

Influence of a paclitaxel coated balloon in combination with a bare metal stent on restenosis and endothelial function: comparison with a drug eluting stent and a bare metal stent.

AIMS: Different approaches of local intravascular drug delivery may influence endothelial and microvascular function. The aim of this trial was to study the influence of a paclitaxel coated balloon in combination with a bare metal stent (DCB + BMS) versus a bare metal stent (BMS) or a sirolimus-eluting stent (DES) on coronary restenosis and endothelial function. METHODS AND RESULTS: This prospective trial included 77 patients with coronary de novo lesions. The patients were assigned to either one of the treatment groups. After 9 months, patients underwent angiographic follow-up including invasive measurement of coronary endothelial function. After 9 months, late lumen loss in-stent was highest in the BMS group (0.85 ± 0.73 mm), lower in DCB + BMS (0.36 ± 0.46 mm); and lowest in the DES group (0.25 ± 0.34 mm; P = 0.001 [ANOVA]). When compared to the BMS group, in-segment late lumen loss was significantly reduced in the DCB + BMS group (0.27 ± 0.43 mm vs. 0.60 ± 0.55 mm, P = 0.029) and the DES group (0.28 ± 0.40 mm, P = 0.045). Coronary flow reserve was significantly higher with the DCB + BMS treatment (3.16 ± 0.97 vs. 2.42 ± 0.99 [BMS], P = 0.036) whereas the increase in the DES group did not reach the significance level (3.06 ± 1.39, P = 0.144 vs. BMS). Parameters of endothelial function like intracoronary flow velocity and vessel diameter distal to the stented area showed similar patterns of response to adenosine, acetylcholine, and nitro in all groups. CONCLUSION: DES and the combination of DCB + BMS showed a significant reduction of late lumen loss as compared to a BMS alone. Furthermore, both types of local drug delivery were not associated with a deterioration of microvascular function at 9 months [ClinicalTrials.gov Identifier: NCT00473499].

Inhibition of neo-intimal hyperplasia in porcine coronary arteries utilizing a novel paclitaxel-coated scoring balloon catheter.

OBJECTIVE: Scoring balloons are particularly useful in the acute treatment of fibro-calcific, bifurcation and in-stent restenosis lesions but have not been shown to affect the restenosis rate. Conventional balloons coated with paclitaxel have recently been shown to reduce restenosis rates in certain lesion subsets, but are associated with suboptimal acute results. A novel paclitaxel-coated scoring balloon was developed to overcome these limitations. DESIGN: AngioSculpt(®) scoring balloons (SB) were coated with paclitaxel admixed with a specific excipient. SETTING AND INTERVENTIONS: Four in vitro and in vivo studies were performed: (a) loss of the drug during passage to the lesion, (b) transfer of the drug to the vessel wall; (c) inhibition of neo-intimal proliferation in porcine coronary arteries as compared to uncoated SB and the Paccocath™, and (d) evaluation of the dose-response to 1.5-12 µg of paclitaxel/mm(2) . MAIN OUTCOME MEASURES AND RESULTS: Drug loss during delivery to the lesion was 17% ± 8%, and transfer to the vessel wall was 9% ± 4% of dose on unused balloons. The paclitaxel-coated SB resulted in a lower late lumen loss of 0.27 ± 0.24 mm compared to 1.4 ± 0.7 mm with the uncoated SB (P = 0.001). Histomorphometry revealed larger luminal areas of 6.8 ± 1.6 mm(2) (paclitaxel-coated SB) and 5.8 ± 1.7 mm(2) (Paccocath) as compared to the uncoated SB (2.3 ± 1.5 mm(2) ; P = 0.001). No coating related adverse effects were observed on follow-up angiography or histologic examination at the treatment site or downstream myocardium. CONCLUSION: A novel paclitaxel-coated SB leads to a significant inhibition of neointimal proliferation in the porcine coronary model.

Long-term effects on vascular healing of bare metal stents delivered via paclitaxel-coated balloons in the porcine model of restenosis.

BACKGROUND: Clinical trials have consistently demonstrated benefits of paclitaxel-coated balloons (PCB) in particular clinical situations such as in-stent restenosis and peripheral vascular interventions. However, the long-term vascular effects of bare metal stents (BMS) delivered via PCB (PCB+BMS) are still unknown. The aim of this study was to assess the long-term effects of PCB+BMS on vascular healing and neointimal formation (NF). METHODS: A total of 208 stents: 56 BMS crimped on PCB, 50 BMS crimped on uncoated balloons (UCB+BMS), 52 Taxus and 50 Cypher stents were implanted in normal coronary arteries of 104 pigs using 1.2:1.0 stent-to-artery ratio. Follow-up occurred at 3, 7, 28, 90, and 180 days. Vascular effects were assessed based on angiographic and histological analysis. Endothelialization was evaluated using an anti von-Willebrand Factor stain. RESULTS: At 28 days, delivery of a BMS using a PCB led to a significant reduction in NF compared to the UCB+BMS and the Taxus stent (P < 0.01). Between 28 and 180 days, the progression of NF tended to be lower in the PCB+BMS compared to all DES groups. At 90 days, the PCB+BMS (2.56 ± 0.43) and the Taxus stents (2.60 ± 0.59) had a trend toward higher inflammatory scores compared to the UCB+BMS group (1.85 ± 1.13, P = 0.09). By 180 days, inflammation and NF had completely normalized between the groups. Expression of peristrut vWF was comparable among all tested groups at 28 days. CONCLUSION: The long-term pattern of vascular healing occurring following PCB+BMS deployment appears to be comparable to what has been reported with DES technologies.

Survival After Coronary Revascularization With Paclitaxel-Coated Balloons.

BACKGROUND: Drug-coated balloons (DCBs) are accepted treatment strategies for coronary in-stent restenosis and are under clinical investigation for lesions without prior stent implantation. A recently published meta-analysis suggested an increased risk of death associated with the use of paclitaxel-coated devices in the superficial femoral artery. The reasons are incompletely understood as potential underlying pathomechanisms remain elusive, and no relationship to the administered dose has been documented. OBJECTIVES: The purpose of this analysis was to investigate the available data on survival after coronary intervention with paclitaxel-coated balloons from randomized controlled trials (RCTs). METHODS: PubMed, Web of science, and the Cochrane library database were searched, and a meta-analysis from RCT was performed comparing DCB with non-DCB devices (such as conventional balloon angioplasty, bare-metal stents, or drug-eluting stents) for the treatment of coronary in-stent restenosis or de novo lesions. The primary outcome was all-cause death. The number of patients lost to follow-up was observed at different time points. Risk estimates are reported as risk ratios (RRs) with 95% confidence intervals (CIs). RESULTS: A total of 4,590 patients enrolled in 26 RCTs published between 2006 and 2019 were analyzed. At follow-up of 6 to 12 months, no significant difference in all-cause mortality was found, however, with numerically lower rates after DCB treatment (RR: 0.74; 95% CI: 0.51 to 1.08; p = 0.116). Risk of death at 2 years (n = 1,477, 8 RCTs) was similar between the 2 groups (RR: 0.84; 95% CI: 0.51 to 1.37; p = 0.478). After 3 years of follow-up (n = 1,775, 9 RCTs), all-cause mortality was significantly lower in the DCB group when compared with control treatment (RR: 0.73; 95% CI: 0.53 to 1.00; p = 0.047) with a number needed to treat of 36 to prevent 1 death. A similar reduction was seen in cardiac mortality (RR: 0.53; 95% CI: 0.33 to 0.85; p = 0.009). CONCLUSIONS: In this meta-analysis, the use of paclitaxel DCBs for treatment of coronary artery disease was not associated with increased mortality, as has been suggested for peripheral arteries. On the contrary, use of coronary paclitaxel-coated balloons was associated with a trend toward lower mortality when compared with control treatments.

Bare metal or drug-eluting stent versus drug-coated balloon in non-ST-elevation myocardial infarction: the randomised PEPCAD NSTEMI trial.

AIMS: Drug-coated balloons (DCB) may avoid stent-associated long-term complications. This trial compared the clinical outcomes of patients with non-ST-elevation myocardial infarction (NSTEMI) treated with either DCB or stents. METHODS AND RESULTS: A total of 210 patients with NSTEMI were enrolled in a randomised, controlled, non-inferiority multicentre trial comparing a paclitaxel iopromide-coated DCB with primary stent treatment. The main inclusion criterion was an identifiable culprit lesion without angiographic evidence of large thrombus. The primary endpoint was target lesion failure (TLF; combined clinical endpoint consisting of cardiac or unknown death, reinfarction, and target lesion revascularisation) after nine months. Secondary endpoints included total major adverse cardiovascular events (MACE) and individual clinical endpoints. Mean age was 67±12 years, 67% were male, 62% had multivessel disease, and 31% were diabetics. One hundred and four patients were randomised to DCB, 106 to stent treatment. In the stent group, 56% of patients were treated with BMS, 44% with current-generation DES. In the DCB group, 85% of patients were treated with DCB only whereas 15% underwent additional stent implantation. During a follow-up of 9.2±0.7 months, DCB treatment was non-inferior to stent treatment with a TLF rate of 3.8% versus 6.6% (intention-to-treat, p=0.53). There was no significant difference between BMS and current-generation DES. The total MACE rate was 6.7% for DCB versus 14.2% for stent treatment (p=0.11), and 5.9% versus 14.4% in the per protocol analysis (p=0.056), respectively. CONCLUSIONS: In patients with NSTEMI, treatment of coronary de novo lesions with DCB was non-inferior to stenting with BMS or DES. These data warrant further investigation of DCB in this setting, in larger trials with DES as comparator (ClinicalTrials.gov Identifier: NCT01489449).

Drug Distribution and Basic Pharmacology of Paclitaxel/Resveratrol-Coated Balloon Catheters.

PURPOSE: To experimentally investigate a new homogenously paclitaxel/resveratrol-coated balloon catheter in terms of transport of the coating to the treated tissue and local effects including histology and functional tests. METHODS: Adherence of the coating to the balloon was explored by in vitro simulation of its passage to the lesion. Paclitaxel and resveratrol transfer to the vessel wall was investigated in porcine coronary and peripheral arteries. Matrix-assisted laser desorption/ionization (MALDI) was used for direct microscopic visualization of paclitaxel in arterial tissue. Inhibition of neointimal proliferation and tolerance of complete coating and resveratrol-only coating was investigated in pigs 4 weeks after treatment, and the effect of resveratrol on inflammation and healing after 3 and 7 days. RESULTS: Drug loss on the way to the lesion was < 10% of dose, while 65 ± 13% was detected at the site of balloon inflation. After treatment similar proportions of drug were detected in coronary and peripheral arteries, i.e., 7.4 ± 4.6% of dose or 125 ± 74 ng/mg tissue. MALDI showed circumferential deposition. Inhibition of neointimal proliferation by paclitaxel/resveratrol coating was significant (p = 0.001) whereas resveratrol-only coating did not inhibit neointimal proliferation. During the first week after treatment of peripheral arteries with resveratrol-only balloons, we observed nominally less inflammation and fibrin deposition along with a significant macrophage reduction and more pronounced re-endothelialization. No safety issues emerged including left ventricular ejection fraction for detection of potential distal embolization after high-dose treatment of coronary arteries. CONCLUSIONS: Paclitaxel/resveratrol-coated balloons were effective and safe in animal studies. Beyond acting as excipient resveratrol may contribute to vascular healing.

The PPAR-gamma agonist pioglitazone increases neoangiogenesis and prevents apoptosis of endothelial progenitor cells.

PPAR-gamma agonists (thiazolidinediones, TZDs) may improve endothelial function independently of insulin sensitizing. Bone marrow-derived endothelial progenitor cells (EPC) contribute to neoangiogenesis. Mice were treated with pioglitazone, 20mg/kg/day for 10 days. Treatment with TZD upregulated circulating Sca-1/VEGFR-2 positive EPC in the blood (235+/-60%) and the bone marrow (166+/-30%), cultured spleen-derived DiLDL/lectin positive EPC increased to 231+/-21% (n=24 per group). Upregulation of EPC was persistent after 20 days. TZD increased SDF-1-induced migratory capacity per number of EPC by 246+/-73% and increased expression of telomere repeat-binding factor 2 by 320+/-50%. In vivo neoangiogenesis was increased two-fold (214+/-42%, 20 days). The NOS inhibitor L-NAME did not inhibit the TZD-induced upregulation of EPC. EPC from TZD-treated animals showed reduced in vivo apoptosis (65+/-2.8% of vehicle). In cultured human EPC, pre-treatment with pioglitazone prevented H(2)O(2)-induced apoptosis. Inhibition of EPC apoptosis by TZD was abolished in the presence of wortmannin but not by LNMA. In summary, TZD upregulates both number and functional capacity of endothelial progenitor cells. Pioglitazone prevents apoptosis of EPC in mice as well as in human EPC in a PI3K-dependent but NO-independent manner. Reduction of EPC apoptosis by TZD may be a potentially beneficial mechanism for patients with vascular diseases.

A novel constrained, paclitaxel-coated angioplasty balloon catheter.

AIMS: The study aimed to assess drug adherence, transfer to the vessel wall, tolerance and efficacy of a constrained angioplasty balloon coated with an excipient-enhanced paclitaxel coating (Chocolate coated balloon [CCB]) in the porcine model. METHODS AND RESULTS: Drug adherence was investigated in vitro. Drug transfer was evaluated in porcine arteries. A stent overstretch model was chosen to provoke intimal thickening in the efficacy and tolerance study. Conventional uncoated balloons were used as controls. CCB were coated with a nominal (3 µg/mm2) and high dose (two completely overlapping inflations each at 6 µg/mm2) of paclitaxel. Efficacy was assessed by histomorphometry and quantitative coronary angiography (QCA). Tolerance, including potential downstream effects, was assessed by myocardial function and histopathology. The CCB lost 6±12% of dose during in vitro simulated delivery to the lesion; drug transfer to the vessel wall was 14±4%. QCA and histomorphometry revealed no baseline differences between treatment groups. Thirty days after treatment, both doses of the CCB resulted in a 50% reduction in neointimal thickening of arteries relative to the uncoated balloon group. Maximum neointimal thickness was 1.12±0.36 mm for uncoated control specimens and 0.46±0.06 mm and 0.44±0.30 mm for the two CCB doses (3 and 2×6 µg/mm2), respectively. There were no device-related animal deaths or changes in left ventricular ejection fraction or device-specific myocardial histopathologies. There were no statistically significant differences between inflammatory scores among treatment groups. CONCLUSIONS: The results demonstrate efficacy and tolerance of a mechanically unique constrained angioplasty balloon within the tested dose range of the selected paclitaxel coating in the chosen porcine preclinical model.

Treatment of chronic total occlusions in native coronary arteries by drug-coated balloons without stenting - A feasibility and safety study.

BACKGROUND: Chronic total occlusions remain one of the biggest challenges for interventional cardiologists and the high risk of restenosis and stent thrombosis is still a major problem. Drug-coated balloons showed favorable results for the treatment of in-stent restenosis and other lesion types. The aim of this study was to evaluate the feasibility and outcome of a drug-coated balloon only approach for chronic total occlusion. METHODS: We included 34 patients with a native chronic total occlusion treated only by drug-coated balloons. A visual residual stenosis of 30% or less without major dissection was considered a satisfactory percutaneous intervention result according to the German Consensus Group recommendations for drug-coated balloon use. We collected clinical and procedural data. Angiograms were conducted during the procedure and at follow-up. Quantitative coronary analysis was performed and mean and minimal lumen diameter and late luminal changes were assessed. RESULTS: The recanalization was considered satisfactory in 79.4% (n=27). Restenosis occurred in 11.8% (n=4) and reocclusion in 5.9% (n=2). Out of the 27 patients with a satisfactory initial result, 3.7% (n=1) had reocclusion and 3.7% (n=1) had restenosis. In the subgroup without satisfactory result (n=7), restenosis occurred in 3 patients (42.9%) and reocclusion in 1 patient (14.3%). A luminal increase was found in 67.6% (n=23) and mean late luminal gain was 0.11±0.49mm. Angina class improved significantly (p<0.001). There was no death or myocardial infarction. CONCLUSIONS: Drug-coated balloon angioplasty without stenting is a feasible and well-tolerated treatment method for chronic total occlusions if the predilatation result is good.

Local paclitaxel induces late lumen enlargement in coronary arteries after balloon angioplasty.

BACKGROUND: This study investigated p aclitaxel-induced luminal changes following drug-coated balloon (DCB) angioplasty to treat coronary de novo lesions without additional stenting. DCB-mediated local drug delivery reduces late lumen loss in de novo coronary artery lesions. We performed a retrospective clinical assessment based on a pre-specified quantitative coronary angiography (QCA) protocol. METHODS: QCA was performed for each centre to assess the primary endpoint late lumen changes, i.e. the difference between in-lesion minimal lumen diameter (MLD) at the routine angiographic follow-up as compared to post-procedural in-lesion MLDs. These MLD changes were compared to corresponding reference vessel diameter changes as an intra-patient control. RESULTS: We evaluated 58 consecutive native coronary artery lesions directly after DCB angioplasty and at a routine target follow-up angiography of 4 months by QCA. Target lesion MLD increased significantly within the 4.1 ± 2.1 month observation period (1.75 ± 0.55 vs. 1.91 ± 0.55 mm, p < 0.001, diameter stenosis 33.8 ± 12.3 vs. 26.9 ± 13.8 %, p < 0.001), while there were no changes in non-target reference vessel diameters (2.33 ± 0.60 vs. 2.34 ± 0.61 mm, p = ns). A total of 69 % of patients showed luminal enlargement whereas 29 % had minor luminal loss. CONCLUSION: Local application of paclitaxel by DCB angioplasty to native coronary arteries after pre-dilatation without major dissection and recoil leads to late lumen increase.

Compassionate use of a paclitaxel coated balloon in patients with refractory recurrent coronary in-stent restenosis.

OBJECTIVE: Treatment of coronary in-stent restenosis (ISR) remains a challenge in interventional cardiology, especially after drug eluting stent (DES)-ISR. Drug coated balloons (DCB) provide a new therapeutic option in the treatment of ISR. In patients with multiple layers of stents due to refractory ISR and exclusion criteria for revascularization by coronary artery bypass grafting, DCB may be a last therapy option. This paper presents DCB therapy as compassionate use treatment before the balloons were available in Europe. PATIENTS: Compassionate use of DCB was approved by the local ethical committee. Fifteen patients with refractory ISR in 28 lesions were prospectively enrolled between 12/2006 and 04/2009. The frequency of prior ISR was 3.0 ± 1.1. Nine patients presented with coronary three-vessel disease and six patients with one- or two-vessel disease. Thirteen patients had DES-ISR, two patients with contraindication for prolonged dual anti-platelet therapy repeated BMS-ISR. Two or three layers of metal were present in eleven patients. Four patients had prior coronary artery bypass grafting. RESULTS: All lesions were treated with DCB (SeQuent™ Please, B.Braun, Germany). Angiographic follow-up was obtained in 14 patients. Clinical follow-up was available in all patients after 3.2 ± 0.8 years (maximum 4.8 years). Target lesion revascularization was done in 2 of 28 lesions (7.1 %), one patient with ischemic cardiomyopathy died after 1.5 years. No further MACE occurred. CONCLUSION: DCB appear to be safe and clinically useful in the treatment of ISR. DCB is a new promising option for high-risk patients with refractory ISR.

Treatment of a coronary bifurcation lesion with drug-coated balloons: lumen enlargement and plaque modification after 6 months.

We report a male with a coronary bifurcation lesion in the mid circumflex artery (CX). After predilatation, the lesion was treated with two drug-coated balloons (DCB). Primary success in the posterolateral branch was good; however the CX lesion had a residual stenosis including a non-flow-limiting type A dissection. After 6 months, angiography showed slight lumen enlargement in both branches of the bifurcation. Intravascular ultrasound identified about 35 % atherosclerotic plaque load within the inner area of the bifurcation but more than 50 % concentric atherosclerotic plaque burden in the vessel areas proximal and distal to the DCB-treated area.

Inhibition of neointimal proliferation after bare metal stent implantation with low-pressure drug delivery using a paclitaxel-coated balloon in porcine coronary arteries.

A variety of mechanical and laser-based methods remove or shift atherosclerotic plaques and reopen the artery to its original lumen. Subsequent treatment with drug-coated balloons (DCB) may smooth the vessel wall but does not require high-pressure inflation. We investigated the efficacy of paclitaxel-coated balloons inflated with only 2 atm after bare metal stent implantation in coronary arteries of 24 pigs. Angiography and histomorphometry was performed on day 28. DCB inflated with 2 atm caused similar reduction of late lumen loss (LLL) as high-pressure inflation with 12 atm (0.89 ± 0.58 vs. 0.72 ± 0.39 mm, p = 0.34). Both DCB treatments significantly (p < 0.01) reduced LLL versus uncoated balloons (1.50 ± 0.51 mm). Treatment with low-pressure DCB resulted in less maximal intimal thickness (0.45 ± 0.15 vs. 0.67 ± 0.25 mm) and neointimal area (2.93 ± 0.73 vs. 3.82 ± 1.27 mm(2)) than treatment with uncoated balloons (p < 0.05). In conclusion, low-pressure treatment with DCB was similarly effective as high-pressure treatment justifying clinical trials in vessels which will benefit from inhibition of neointimal proliferation but may not tolerate high inflation pressure.

Do pharmacokinetics explain persistent restenosis inhibition by a single dose of paclitaxel?

BACKGROUND: The purpose of this study was to investigate the elimination of paclitaxel from the arterial wall after a single short administration with a coated balloon. METHODS AND RESULTS: Slightly oversized paclitaxel-coated balloons (dose 3 or 9 µg/mm(2)) without or with premounted stents were inflated in nonatherosclerotic coronary arteries of either young domestic pigs or adult Goettingen minipigs. The paclitaxel content of plasma, arterial segments, and residual hearts (without treated arteries) was measured for up to 180 days using high-performance liquid chromatography/ultraviolet detection or mass spectrometry. Angiograms were evaluated for lumen narrowing. The paclitaxel concentration in plasma remained <10 ng/mL. In arteries of domestic pigs and minipigs treated with paclitaxel-coated balloons with premounted stents, 10%±5% or 21%±8% of dose, respectively, was initially detected and decreased to 3.5%±3.1% of dose (domestic pig) by Day 7. Within 6 months it fell with a half-life of 1.9 months to 0.40%±0.35%. After 3 months the concentration in the arterial wall was 17±11 µmol/L. Without a stent, drug transfer to the vessel wall was somewhat reduced and elimination faster. Immediately after treatment up to 26%±4% of dose was detected in the residual whole hearts. It dropped with a half-life of 45 days to 1.5%±0.6% of dose (0.3 µmol/L) within 6 months. CONCLUSIONS: After a single local administration with coated balloons, paclitaxel stays in the vessel wall of pigs long enough to explain persistent inhibition of neointimal proliferation. The pharmacokinetics of paclitaxel does, however, not exclude other reasons for sustained efficacy such as early blocking of processes initiating excessive and prolonged neointimal proliferation.

Inhibition of neointimal hyperplasia with a novel zotarolimus coated balloon catheter.

BACKGROUND: Non stent based delivery of antiproliferative agents using drug coated balloon catheters may offer additional flexibility and efficacy in a broad range of applications. The lipophilic antiproliferative drug zotarolimus makes it a potential candidate for balloon delivery. The aim of the present study was to evaluate the safety and efficacy of a prototype zotarolimus coated balloon (ZCB) catheter in comparison to a zotarolimus eluting stent (ZES) in the porcine coronary overstretch model. METHODS: Eighty-four stents (diameters 3.0 and 3.5 mm; length 15 mm) were implanted in LAD and Cx of 42 domestic pigs: control (TriMaxx, Abbott, polymer coated stent without drug, implanted with uncoated PCI catheter, n = 56); ZES (ZoMaxx, Abbott, stent coated with zotarolimus in polymer, implanted with uncoated PCI catheter, n = 14); ZCB (TriMaxx, Abbott, polymer coated stent without drug, implanted with zotarolimus coated PCI catheter, n = 14). Drug content of the vessel wall (n = 9) was measured about 10-30 min post intervention with ZCB in additional pigs. RESULTS: Immediately after ZCB treatment 101 ± 31 µg of zotarolimus was detected in the coronary arteries. After 28 days ZES led to a reduction of neointimal area from 4.32 ± 1.45 to 3.32 ± 1.11 mm2 (P = 0.019 vs. control). The effect of neointimal inhibition was more pronounced with the novel ZCB (2.79 ± 1.43 mm², P = 0.001 vs. control). Inflammation score was significantly reduced in vessels treated with the ZCB (0.75 ± 0.86 compared to control (1.45 ± 0.94, P = 0.013) and ZES (1.65 ± 0.90, P = 0.012). CONCLUSION: Zotarolimus coated balloons and stents were found to effectively reduce neointimal proliferation in the porcine coronary model. Inflammation scores were significantly reduced after treatment with the coated balloon. Zotarolimus balloon coating might be a novel option in preventing and treating restenosis.

Long-term follow-up after treatment of coronary in-stent restenosis with a paclitaxel-coated balloon catheter.

OBJECTIVES: This study presents long-term clinical follow-up, including binary restenosis rate and major adverse cardiovascular events, of the PACCOCATH-ISR (Treatment of In-Stent Restenosis by Paclitaxel Coated PTCA Balloons) I and II trial. BACKGROUND: The PACCOCATH-ISR trial was a first-in-human study with a drug-coated balloon catheter and the first study for the treatment of coronary ISR with a drug-coated balloon. So, far no long-term follow-up data have been presented. METHODS: This study enrolled 108 patients in a randomized, double-blinded multicenter trial on the efficacy and safety of a paclitaxel-coated balloon (3 µg/mm(2) balloon surface; PACCOCATH [Bayer AG, Germany]) compared with an uncoated balloon. The main inclusion criteria were a diameter stenosis of ≥ 70% and <30-mm length with a vessel diameter of 2.5 to 3.5 mm. The primary endpoint was angiographic late lumen loss in-segment after 6 months. Combined antiplatelet therapy was continued only for 1 month followed by treatment with aspirin alone. RESULTS: During a follow-up of 5.4 ± 1.2 years, the clinical event rate was significantly reduced in patients treated with the drug-coated balloon (major adverse cardiovascular events: 59.3% vs. 27.8%, p = 0.009), which was mainly driven by the reduction of target lesion revascularization from 38.9% to 9.3% (p = 0.004). CONCLUSIONS: Treatment of coronary ISR with paclitaxel-coated balloon catheters is safe and persistently reduces repeat revascularization during long-term follow-up. The initial results were sustained over the 5-year period. (Treatment of In-Stent Restenosis by Paclitaxel Coated PTCA Balloons [PACCOCATH ISR I]; NCT00106587. Treatment of In-Stent Restenosis by Paclitaxel Coated PTCA Balloons [PACCOCATH ISR II]; NCT00409981).

Long-term follow-up of early versus delayed invasive approach after fibrinolysis in acute myocardial infarction.

BACKGROUND: Optimal reperfusion strategy in ST-elevation myocardial infarction is controversial. Failure of fibrinolytic therapy is related to limited efficacy, high reocclusion rates, reinfarction, and systemic bleeding complications. Data on the impact of percutaneous coronary intervention (PCI) after fibrinolysis are conflicting. The Southwest German Interventional Study in Acute Myocardial Infarction (SIAM III) evaluated the effects of transfer for early PCI in acute ST-elevation-myocardial infarction compared with a delayed PCI strategy. METHODS AND RESULTS: SIAM III was a multicenter, randomized, prospective, controlled trial in patients with ST-elevation-myocardial infarction receiving fibrinolysis <12 hours after onset of symptoms. All patients received reteplase, aspirin in combination with ticlopidine, and heparin. Patients of the early PCI group were transferred within 6 hours after fibrinolysis for PCI. The delayed PCI group received elective PCI 2 weeks after fibrinolysis. In total, 197 patients were included; 163 were treated by PCI. The primary end point was the composite of death, reinfarction, target lesion revascularization, and ischemic events. During a mean follow-up time of 7.9±3.4 years (maximum, 11.2 years), early PCI was associated with a significant reduction of the primary end point (hazard ratio, 0.61 [95% confidence interval, 0.42 to 0.88]; P=0.008). Long-term survival was higher in the early PCI group (P=0.057). Ischemic events were significantly reduced after early PCI (P=0.003). CONCLUSIONS: Early PCI after fibrinolysis improves long-term event-free survival compared with a delayed PCI treatment strategy.

Dose response to Paclitaxel-coated balloon catheters in the porcine coronary overstretch and stent implantation model.

OBJECTIVE: There is little published information regarding the efficacy of paclitaxel-coated balloon catheters except for the iopromide-containing formulation, and less is known about the kind of toxicity at overdose. The aim of our study was to assess 2 different paclitaxel matrix formulations on angioplasty balloon catheters in vitro, with respect to pharmacokinetics, and efficacy and tolerance to determine the minimum effective dose and local toxicity at extremely high dose which is only achieved in experimental studies. METHODS AND MATERIALS: Adherence of coatings was tested in vitro in dry state and during passage through hemostatic valves, guiding catheters, and blood. Drug release, transfer to the vessel wall during coronary angioplasty, inhibition of neointimal proliferation, and tolerance were investigated in swine. Efficacy and tolerance of balloons were examined for doses ranging from 1 to 9 µg/mm2 and 3 overlapping applications of balloons coated with 3 times the regular dose of 3 µg/mm2. Paclitaxel concentrations were determined by high performance liquid chromatography, efficacy and tolerance by vital signs, clinical observation, quantitative coronary angiography, and histomorphometry 4 weeks after implanting premounted bare stents in coronary arteries applying 1:1.2 overstretch. RESULTS: Under worst-case conditions, drug loss on the way through the guiding catheter and blood was in the range of 30%. After inflation of balloons coated with the clinically tested dose of 3 µg/mm2 in a coronary artery about 10% of drug remained on balloons, 20% to 30% was taken up into the vessel wall (∼200 µg). Neointimal area on cross sections was 6.8 ± 2.2 mm2 (uncoated control); 3.1 ± 1.1 mm2 (iopromide-matrix) and 3.0 ± 0.5 mm2 (urea-matrix) at 1 µg/mm2; 2.0 ± 0.4 mm2 versus 1.7 ± 1.1 mm2 at 3 µg/mm2 with no further decrease at higher doses. Thrombotic occlusions were observed in 3 of 15 vessel segments treated with overlapping inflations of 3 high-dose balloons but without any signs of aneurysms. CONCLUSION: In the animal model, 2 paclitaxel matrix formulations were similar in respect of uptake in the vessel wall, and effective already at a dose of 1 µg/mm2. Except thrombotic events for the intentionally excessive dose, paclitaxel-coated balloons were well tolerated in the animal model.

Paclitaxel and sirolimus differentially affect growth and motility of endothelial progenitor cells and coronary artery smooth muscle cells.

AIMS: EPC and hCASMC play an important role in the pathogenesis of restenosis and stent thrombosis. Drug-coated balloon catheters exert a local, short-term application of antiproliferative agents. This study investigates the time-dependent influence on growth and motility of paclitaxel and sirolimus alone and combined with the coating additive iopromide on EPC and hCASMC. METHODS AND RESULTS: Treatment of cultured human EPC and hCASMC with paclitaxel and sirolimus 1.5 and 15 µM for three seconds, three minutes and 24 hours, alone or combined with iopromide 0.197 M, resulted in a concentration- and time- dependent inhibition of proliferation and of migration. Paclitaxel and sirolimus increase apoptosis in either cell type. However, the effects of paclitaxel and sirolimus differed between the cell types: short-term exposure with paclitaxel leads to stronger inhibition of cell-density and apoptosis of hCASMC compared to EPC. In comparison to paclitaxel, short-term incubation with sirolimus showed a more effective inhibition of cell-density and migration as well as increased apoptosis in EPC in contrast to hCASMC. The effects of paclitaxel and sirolimus were increased in combination with iopromide. Interestingly, the antiproliferative effect of the paclitaxel-iopromide formulation on hCASMC was more potent compared to its effect on EPC. Endothelialisation in a porcine coronary stent model was similar with drug-coated balloons and uncoated controls, whereas it was delayed with drug-eluting stents. CONCLUSION: After short-term application, paclitaxel and sirolimus show differential, cell-specific effects on EPC and hCASMC. Iopromide used as a coating agent intensifies these effects.