Abstract
Because of anticipated antiplatelet medication risks, patients who are not DES candidates or who are at particularly high risk for bleeding events have been targeted initially for treatment with the COBRA PzF Coronary Stent System. We report the case of a successful experience with a new, Polyzene™-F COBRA PzF™ Coronary Stent System, designed to impart thrombo-resistance and reduce inflammation, to achieve shorter dual antiplatelet therapy duration while reducing restenosis incidence in a high risk patient with atrial fibrillation.
1
Introduction
Even with the use of new-generation drug-eluting stents (DES), stent thrombosis and major adverse cardiac and cerebrovascular events (MACCE; composite of death, myocardial infarction or stroke) continue to be clinical risks associated with coronary stent placement. Mitigation of these risks is accomplished with consideration of the patient’s comorbidities and stent selection. Typically, stent choice requires pharmacologic antiplatelet medication for a minimum of 1 month of dual antiplatelet therapy (DAPT; combination of ASA and a P2Y12 inhibitor) post bare metal stent (BMS) placement or for a minimum of 6–12 months DAPT after placement of a drug-eluting stent (DES) per ACCF/AHA/SCAI 2011 PCI and ESC/EACTS 2014 Guidelines on elective percutaneous coronary intervention (PCI) .
Patients treated for atrial fibrillation (AF) are at additional risk when undergoing PCI. Combining chronic oral anticoagulation (OAC) therapy with DAPT, resulting in triple antithrombotic therapy, has been and continues to be intensely scrutinized. Prevention of thromboembolic (stroke) and atherothrombotic (stent thrombosis) events is balanced against the increase risk of severe bleeding in all, but in particular, the triple therapy patients . Careful deliberation includes reducing the duration of or eliminating one or more antithrombotic medications as well as consideration of alternative stent designs for patients at higher risk of bleeding events.
A middle ground in stent design, available through use of Polyzene™-F nano-coating, is designed to impart thrombo-resistance and reduce in-situ inflammation. This coating on the COBRA PzF™ Coronary Stent System offers a compromise position by shortening DAPT duration to one month with the potential of reducing restenosis incidence. Patients who are not DES candidates or who are at higher risk for bleeding events have been targeted initially for treatment with the COBRA PzF Coronary Stent System and this report provides a description of one of the first uses of the device system with its special properties.
2
Case report
A 72-year-old female with a history of significant comorbidities, including atrial fibrillation, angina (CCS III), arterial hypertension, heart failure, hyperlipidemia, diabetes mellitus type 2 and history of ischemic stroke, was diagnosed with a 75% stenotic mid-LAD lesion; see Fig. 1 .
Additional risk assessments included a CHA 2 DS 2 -VASc score of 7, which is associated with a 9.6% per year risk of stroke without warfarin treatment , and a HAS-BLED score of 4, which is associated with a 4.9%–19.6% one year bleeding risk while on oral anticoagulants . This particular subject’s specific, but not atypical, profile places her at significant bleeding risk so appropriate stent selection was critical. In April 2014, she received a cobalt chromium alloy COBRA PzF Stent with Polyzene™-F nano-coating (CeloNova BioSciences, Inc., San Antonio, Texas). The COBRA PzF Stent (CE marked) is indicated for improving coronary luminal diameter in patients with symptomatic ischemic heart disease due to coronary artery lesions and is intended for use in patients eligible for percutaneous transluminal coronary angioplasty (PTCA, PCI) with reference vessel diameter of 2.5–4.0 mm.
With 5F guide catheter compatibility and low (0.89 mm) crossing profile, due in part to the thin (71 μm) struts, the COBRA PzF stent proved its deliverability. Stent delivery and deployment were unremarkable and the stent’s radiopacity permitted an appreciation of full apposition within the target vessel; see Fig. 2 .
2.1
Medical therapy
Post-procedure antiplatelet therapy consisted of clopidogrel (75 mg) and acetylsalicylic acid (100 mg) daily for 4 weeks. Due to atrial fibrillation, phenprocoumon, a coumarin vitamin K antagonist, was administered, targeting an INR of 2.0–2.5, during the same 4 week period, after which rivaroxaban (20 mg), a direct factor Xa inhibitor, was prescribed daily. The modification in anticoagulation regimen from phenprocoumon to rivaroxaban after 4 weeks was made on the patients’ desire to avoid INR controls and require as few tablets as possible. This anticoagulation regimen may also have a reduction of hemorrhagic infarcts . Aspirin was stopped after 4 weeks, in accordance with the consensus document . No medication compliance concerns were noted.
2.2
Follow-up
To date, the patient has not experienced any adverse or serious adverse events. Assessments have been made, including clinic visits and ECGs, in-hospital and at 30, 180 and 270 days post-procedure. The patient has reported a decrease in symptoms and increased physical activity has been observed.
2
Case report
A 72-year-old female with a history of significant comorbidities, including atrial fibrillation, angina (CCS III), arterial hypertension, heart failure, hyperlipidemia, diabetes mellitus type 2 and history of ischemic stroke, was diagnosed with a 75% stenotic mid-LAD lesion; see Fig. 1 .
Additional risk assessments included a CHA 2 DS 2 -VASc score of 7, which is associated with a 9.6% per year risk of stroke without warfarin treatment , and a HAS-BLED score of 4, which is associated with a 4.9%–19.6% one year bleeding risk while on oral anticoagulants . This particular subject’s specific, but not atypical, profile places her at significant bleeding risk so appropriate stent selection was critical. In April 2014, she received a cobalt chromium alloy COBRA PzF Stent with Polyzene™-F nano-coating (CeloNova BioSciences, Inc., San Antonio, Texas). The COBRA PzF Stent (CE marked) is indicated for improving coronary luminal diameter in patients with symptomatic ischemic heart disease due to coronary artery lesions and is intended for use in patients eligible for percutaneous transluminal coronary angioplasty (PTCA, PCI) with reference vessel diameter of 2.5–4.0 mm.
With 5F guide catheter compatibility and low (0.89 mm) crossing profile, due in part to the thin (71 μm) struts, the COBRA PzF stent proved its deliverability. Stent delivery and deployment were unremarkable and the stent’s radiopacity permitted an appreciation of full apposition within the target vessel; see Fig. 2 .
