CRT: Japanese data show promise for Promus Element in small vessels
WASHINGTON, D.C.—The 2.25 mm Promus Element everolimus-eluting stent demonstrated safety and effectiveness in the PLATINUM Japan Small Vessel (SV) study, presented Feb. 6 at the Cardiovascular Research Technologies (CRT) meeting.
Small coronary vessel diameter is associated with high restenosis rates and adverse clinical outcomes, said lead author Shigeru Saito, MD, director of cardiology and catheterization laboratories at Shonan Kamakura General Hospital in Kamakura, Japan.
The PLATINUM trial found that the platinum chromium Promus Element everolimus-eluting stent (Boston Scientific) demonstrated non-inferior clinical outcomes, compared with Xience V (Abbott) in arteries at least 2.5 mm (J Am Coll Cardiol 2011;57:1700-1708). Thus, Saito and his colleagues conducted the prospective, multicenter Japan Small Vessel study to assess results in small caliber arteries less than 2.5 mm in Japan.
The researchers targeted single de novo lesion at least 28 mm long, native coronary artery 2.25 mm or less to less than 2.50 mm in diameter (visual estimate), stenosis at least 50 percent and less than 100 percent with TIMI flow greater than 1.
The primary endpoint of the trial was major adverse cardiac events at nine months in the intent-to-treat analysis set assessing cardiac death, MI or ischemia-driven target lesion revascularization. The pre-specified performance goal of 24.1 percent was based on historical balloon angioplasty results (chosen because there were no commercially available small diameter [less than 2.5 mm] everolimus-eluting stents in Japan when the study was designed), according to Saito.
The researchers enrolled 60 patients at 14 sites, randomizing at a 1:1 basis to an angiography subset (32 patients, 29 patients with angiographies completed) or no-angiography subset (28 patients). Angiography was performed at the 12-month clinic visit.
Evaluating the two arms, the baseline characteristics of the 60 patients (68.3 percent of the participants were male at an approximate age of 69 years old) with 36.7 percent having diabetes, 76.7 percent having hyperlipidemia, 85 percent having hypertension and 26.7 having had a previous MI.
Saito reported that their pre-procedure medication adherence of thienopyridine and aspirin was 100 percent at pre-PCI and discharge. However, the 12-month rate of aspirin was 100 percent, and the thienopyridine adherence rate was 90 percent.
He also reported that the nine-month rate of major adverse events was zero. “With a one-sided 95 percent upper confidence bound of 4.9 percent, the result is significantly less than the performance goal of 24.1 percent,” Saito said.
There was zero percent of all death, MI, target vessel revascularization, target lesion revascularization and stent thrombosis (Academic Research Consortium definite/probable). Also, the technical success rate per stent and clinical procedural success was reported as 100 percent.
At 369 days, the PLATINUM Japan SV study found that the rates of death, MI and stent thrombosis were zero percent, while the rates of target vessel revascularization (TVR) and target lesion revascularization (TLR) were both 3.3 percent. After angiographic assessments (366 to 396 days), one patient had a TLR and one patient had a TLR plus a non-TLR TVR, Saito explained.
Also, in the angiography subset of 29 patients, in-stent late loss was 0.18 mm. Saito reiterated that there were no deaths, MIs, revascularizations or incidence of stent thrombosis through 12-month clinical follow-up.
In commenting on the trial, Ashequl Islam, MD, an interventional cardiologist from Baystate Medical Center in Springfield, Mass., pointed out that U.S. physicians can’t stent lesions based on angiographies. However, Islam acknowledged the clinical standards are different in Japan.
Small coronary vessel diameter is associated with high restenosis rates and adverse clinical outcomes, said lead author Shigeru Saito, MD, director of cardiology and catheterization laboratories at Shonan Kamakura General Hospital in Kamakura, Japan.
The PLATINUM trial found that the platinum chromium Promus Element everolimus-eluting stent (Boston Scientific) demonstrated non-inferior clinical outcomes, compared with Xience V (Abbott) in arteries at least 2.5 mm (J Am Coll Cardiol 2011;57:1700-1708). Thus, Saito and his colleagues conducted the prospective, multicenter Japan Small Vessel study to assess results in small caliber arteries less than 2.5 mm in Japan.
The researchers targeted single de novo lesion at least 28 mm long, native coronary artery 2.25 mm or less to less than 2.50 mm in diameter (visual estimate), stenosis at least 50 percent and less than 100 percent with TIMI flow greater than 1.
The primary endpoint of the trial was major adverse cardiac events at nine months in the intent-to-treat analysis set assessing cardiac death, MI or ischemia-driven target lesion revascularization. The pre-specified performance goal of 24.1 percent was based on historical balloon angioplasty results (chosen because there were no commercially available small diameter [less than 2.5 mm] everolimus-eluting stents in Japan when the study was designed), according to Saito.
The researchers enrolled 60 patients at 14 sites, randomizing at a 1:1 basis to an angiography subset (32 patients, 29 patients with angiographies completed) or no-angiography subset (28 patients). Angiography was performed at the 12-month clinic visit.
Evaluating the two arms, the baseline characteristics of the 60 patients (68.3 percent of the participants were male at an approximate age of 69 years old) with 36.7 percent having diabetes, 76.7 percent having hyperlipidemia, 85 percent having hypertension and 26.7 having had a previous MI.
Saito reported that their pre-procedure medication adherence of thienopyridine and aspirin was 100 percent at pre-PCI and discharge. However, the 12-month rate of aspirin was 100 percent, and the thienopyridine adherence rate was 90 percent.
He also reported that the nine-month rate of major adverse events was zero. “With a one-sided 95 percent upper confidence bound of 4.9 percent, the result is significantly less than the performance goal of 24.1 percent,” Saito said.
There was zero percent of all death, MI, target vessel revascularization, target lesion revascularization and stent thrombosis (Academic Research Consortium definite/probable). Also, the technical success rate per stent and clinical procedural success was reported as 100 percent.
At 369 days, the PLATINUM Japan SV study found that the rates of death, MI and stent thrombosis were zero percent, while the rates of target vessel revascularization (TVR) and target lesion revascularization (TLR) were both 3.3 percent. After angiographic assessments (366 to 396 days), one patient had a TLR and one patient had a TLR plus a non-TLR TVR, Saito explained.
Also, in the angiography subset of 29 patients, in-stent late loss was 0.18 mm. Saito reiterated that there were no deaths, MIs, revascularizations or incidence of stent thrombosis through 12-month clinical follow-up.
In commenting on the trial, Ashequl Islam, MD, an interventional cardiologist from Baystate Medical Center in Springfield, Mass., pointed out that U.S. physicians can’t stent lesions based on angiographies. However, Islam acknowledged the clinical standards are different in Japan.