Clinical outcomes of patients treated with the cutting balloon and Sr-90 beta-irradiation for instent restenosis

Clinical outcome of patients undergoing low aggressive angioplasty combined with brachytherapy and short-term dual antiplatelet therapy for in-stent restenosis

OBJECTIVE

The impact of vessel injury on the outcome of patients undergoing percutaneous coronary intervention combined with brachytherapy for in-stent restenosis is under investigation. We report our clinical experience adopting a low aggressive balloon angioplasty technique, to limit vessel trauma, associated with brachytherapy and short-term dual antiplatelet therapy.

METHODS

Forty-nine consecutive patients, undergoing percutaneous coronary intervention with brachytherapy for symptomatic in-stent restenosis, were prospectively observed for a median time of 21 + or - 8 months. Clinical follow-up included anginal status, death, myocardial infarction and repeat revascularization; only patients with evidence of ischaemia repeated coronary angiography. Low aggressive angioplasty consisted in the use of a conventional balloon with a balloon to artery ratio < or = 1, avoiding high inflation pressures and the use of other devices. Dual antiplatelet therapy was continued for 3-6 months.

RESULTS

Early angiographic result was good and the need for additional stent implantation was low (3.9%). At follow-up, we did not observe death, acute myocardial infarction or stent thrombosis, but 10 patients repeated coronary angiography for recurrence of ischaemia: disease progression was present in two cases (4.1%). Restenosis emerged in the remaining eight patients (16.3%): two cases showed restenosis within the target lesion segment, one case within the injured segment, one case within the radiated segment, and four cases at the edges. The consequent new revascularization was surgical in three patients and percutaneous in seven patients.

CONCLUSIONS

Our data suggest that low aggressive angioplasty followed by brachytherapy and short-term dual antiplatelet therapy for in-stent restenosis is related to a good outcome, with a low restenosis rate and without stent thrombosis.

Angiographic and clinical outcomes at 8 months of cutting balloon angioplasty and beta-brachytherapy for native vessel in-stent restenosis (BETACUT): results from a stopped randomized controlled trial

The objective of this study was to assess angiographic and clinical outcomes of cutting balloon (CB) angioplasty and concomitant Sr/Y-90 beta-brachytherapy as a treatment modality for patients with native vessel in-stent restenosis (ISR). Procedural advantages over the standard balloon (SB) have been claimed for the CB. Intracoronary brachytherapy preceded by SB angioplasty is regarded as the treatment of choice in patients with ISR. In an interim analysis of a prospective randomized trial designed for 652 patients, 100 consecutive patients with ISR were assigned to treatment with SB angioplasty (n = 51) or CB angioplasty (n = 49), followed in either case by Sr/Y-90 beta-brachytherapy. Quantitative coronary angiography at baseline, postintervention, and at 8 months was performed by an independent central laboratory. More than 90% of target lesions in the overall patient population were diffuse, with 14% of stents totally occluded. Procedural parameters and immediate angiographic outcomes were essentially the same in either study arm. At 8 months, no statistically significant differences were observed in recurrent angiographic restenosis (SB = 26.1%; CB = 29.5%; P = 0.82), target lesion revascularizations (SB = 13.7%; CB = 8.2%; P = 0.53), and major adverse cardiac events (SB = 15.7%; CB = 8.2%; P = 0.36). In this interim analysis, there was no indication of a beneficial effect of CB use over SB use in terms of angiographic or clinical outcomes at 8-month follow-up. CB angioplasty appears to be as safe and efficacious as SB angioplasty in beta-radiation treatment of patients with predominantly diffuse native vessel ISR. It was decided to discontinue the trial.

Cutting Balloon: Review on Principles and Background of Use in Peripheral Arteries

This review describes peripheral use of cutting balloon (CB) angioplasty (CBA), its characteristics, and its distinction from conventional BA and describes the experimental and clinical background of its current use in peripheral arteries.

Intracoronary 166Holmium brachytherapy combined with cutting balloon angioplasty for the treatment of in-stent restenosis

BACKGROUND

Brachytherapy is the only effective treatment for in-stent restenosis (ISR). The preliminary data regarding cutting balloon angioplasty (CBA) are encouraging and suggest a possible additive effect of CBA with combination with vascular brachytherapy. Hence, in this study, we evaluated the efficacy, feasibility and safety of cutting balloon angioplasty followed by intracoronary Holmium (166Ho) brachytherapy for the treatment of in-stent restenosis.

METHODS AND MATERIALS

Fifty-six patients with in-stent restenosis were treated with cutting balloon angioplasty and intracoronary 166Ho brachytherapy. For irradiation, a balloon approximately 10 mm longer than the initially deployed stent was filled with liquid 166Ho and placed at the in-stent restenosis lesion. The patients were followed angiographically at 6 months and clinically for 19.0+/-9.8 months.

RESULTS

The initial procedures were successful in all of the patients. The preprocedural average minimal luminal diameter (MLD) and stenosis rate were 0.57+/-0.30 mm and 80.2+/-11.6%, respectively. The MLD and residual stenosis immediately after the procedure was 2.43+/-0.37 and 13.8+/-9.9%, respectively. Thirty-nine (69.6%) patients have completed their angiographic follow-up at 6 months. The MLD, late loss and loss index at follow-up were 1.97+/-0.79 mm, 0.72+/-0.69 mm and 0.36+/-0.34, respectively. The target lesion restenosis rate was 20.5% and the target lesion revascularization rate was 3.6%. None of these patients presented with adverse coronary events such as MI, sudden cardiac death or stent thrombosis during the follow up period.

CONCLUSION

The combination therapy using cutting balloon angioplasty and intracoronary 166Ho brachytherapy may be an effective new treatment modality for in-stent restenosis.

Novel simultaneous combination chemical thrombolysis/rheolytic thrombectomy therapy for acute critical limb ischemia: The power-pulse spray technique

The novel power-pulse spray (P-PS) technique maximizes and combines the advantages and minimizes the disadvantages of both chemical thrombolysis (CT) and rheolytic thrombectomy (RT). Forty-nine consecutive patients with iliofemoral thrombotic occlusion were treated via P-PS technique. Using a 6 Fr RT catheter, saline prime was exchanged for thrombolytic solution [group 1, 10-20 mg tenecteplase (TNK)/50 cc saline, n = 25; group 2, 1,000,000 urokinase (UK)/50 cc saline, n = 24]. The outflow port was closed, then the catheter was advanced at 1 mm increments while pulsing lytic agent. After 30-min lysis time, RT and definitive treatment of the underlying stenosis were performed. Procedure success was 23/25 (92%) and 22/24 (91.6%) for group 1 and 2, respectively. The mean total procedure time was 72 and 75 min in group 1 and 2, respectively. Thirty-day limb salvage was 91% in both groups. There were no major surgical complications. The P-PS technique is safe and effective using either UK or TNK, offering several potential advantages over monotherapy, including more rapid revascularization, decreases systemic lytic exposure and bleeding complications while facilitating both CT and RT capacity and efficacy.

Real-world clinical practice of intracoronary radiation therapy as compared to investigational trials

Intracoronary radiation therapy (IRT) is well established in clinical practice as an effective treatment for in-stent restenosis. We aimed to determine if the 6-month clinical outcome of patients treated postapproval for marketing [commercial radiation (CR)] is equivalent to those patients enrolled in the Washington Radiation for In-Stent Restenosis Trials [Gamma WRIST and Beta WRIST; investigational radiation (IR)]. The 6-month clinical outcome of 110 consecutive patients with 125 lesions who received IRT (gamma, (192)Ir, 15-18 Gy, n = 6; or beta, (32)P, 20 Gy, n = 20; or (90)Sr/Y, 18.4-23.0 Gy, n = 99) in CR was compared with the 6-month clinical outcome of 117 patients with 117 lesions who received IRT ((192)Ir, 15 Gy, n = 65, in Gamma WRIST; and (90)Y, 20.6 Gy, n = 52, in Beta WRIST) in IR. Patients in CR were treated with wider radiation margins. The CR received antiplatelet therapy for at least 6 months and the IR for 1 month. The baseline characteristics of both groups were similar. Use of atheroablation devices was less in CR than IR (15.2% vs. 32.8%, respectively; P = 0.001). The overall major adverse cardiac events (death, Q-wave myocardial infarction, and target vessel revascularization; 18.2% vs. 29.1% in IR; P = 0.05) were significantly lower in the CR when compared with patients in the IR. The real-world clinical practice of IRT demonstrates lower events and better clinical outcomes. This is most likely a result of implementation of the lessons learned from the clinical trials such as optimizing the dosimetry by using a higher dose, treating wider margins to minimize edge effect, and administering prolonged antiplatelet therapy to abolish late thrombosis.

Cutting balloon angioplasty vs. conventional balloon angioplasty in patients receiving intracoronary brachytherapy for the treatment of in-stent restenosis

The objective of this study was to evaluate the safety and efficacy of cutting balloon angioplasty (CBA) for the treatment of in-stent restenosis prior to intracoronary brachytherapy (ICB). Cutting balloon angioplasty may reduce the incidence of uncontrolled dissection requiring adjunctive stenting and may limit "melon seeding" and geographic miss in patients with in-stent restenosis who are subsequently treated with ICB. We performed a retrospective case-control analysis of 134 consecutive patients with in-stent restenosis who were treated with ICB preceded by either CBA or conventional balloon angioplasty. We identified 44 patients who underwent CBA and ICB, and 90 control patients who underwent conventional percutaneous transluminal coronary angioplasty (PTCA) and ICB for the treatment of in-stent restenosis. Adjunctive coronary stenting was performed in 13 patients (29.5%) in the CBA/ICB group and 41 patients (45.6%; P < 0.001) in the PTCA/ICB group. There was no difference in the injury length or active treatment (ICB) length. The procedural and angiographic success rates were similar in both groups. There were no statistically significant differences in the incidence of death, myocardial infarction, recurrent angina pectoris, subsequent target lumen revascularization, or the composite endpoint of all four clinical outcomes (P > 0.05). Despite sound theoretical reasons why CBA may be better than conventional balloon angioplasty for treatment of in-stent restenosis with ICB, and despite a reduction in the need for adjunctive coronary stenting, we were unable to identify differences in clinical outcome.