ABC | Volume 115, Nº1, July 2020

Original Article Pessoa et al. Cost-effectiveness comparison between drug-eluting stents and bare-metal stents Arq Bras Cardiol. 2020; 115(1):80-89 was the same for both stent types, hindering the systematic use of DESs in private services involved in agreements with the Brazilian Ministry of Health. According to data from the DATASUS, 10  in 2008, 44,138 percutaneous coronary interventions (PCIs) were performed with or without stenting. Eight years later, 79,997 PCIs were performed. With this significant increase in procedures (72.84%), it is possible to project an increase in cases of restenosis that could potentially be reduced with more liberal use of DESs in the SUS. Despite the favorable scenario for the full incorporation of DESs into the SUS, scientific evidence based on the Brazilian reality is lacking. Therefore, this study aimed to analyze and estimate the incremental cost-effectiveness ratio (ICER) between DESs and BMSs in SUS patients. Objectives To evaluate the cost-effectiveness and major adverse events of DESs compared with BMSs in patients with single-vessel coronary artery disease undergoing PCI. Methods We conducted a randomized clinical study of patients undergoing PCI from November 2013 to October 2016 at Hospital Universitário Pedro Ernesto (HUPE) and at Hospital São Lucas de Nova Friburgo (HSL), Brazil. The study was approved by the Research Ethics Committees of both institutions, under number 923660. Written informed consent was obtained from each study participant, in accordance with the Brazilian National Health Council Resolution No. 466/2012. A total of 231 patients of both sexes with single-vessel lesions, an indication for PCI after preliminary coronary cineangiography, and symptoms of angina or noninvasive tests showing myocardial ischemia were assessed. The inclusion criteria were (1) age ≥18 years, (2) angiographically significant lesions (>70%) in a coronary artery of great anatomical importance, with irrigation of a large area of ​cardiac muscle, related to the presence of ischemia or typical angina symptoms, (3) single-vessel coronary artery disease, with a lesion amenable to treatment with a single stent, (4) presence or not of diabetes, and (5) stable coronary disease or acute coronary syndrome. The exclusion criteria were (1) multivessel coronary artery disease, (2) injury that required an approach with more than one stent, (3) previous coronary angioplasty with stenting, (4) allergy to aspirin and/or clopidogrel, (5) recent intestinal or genitourinary bleeding (in the last 6 months), (6) active peptic ulcer, (7) major surgery in the past 6 weeks, (8) stroke in the last year or permanent neurological sequelae, (9) pregnancy, and (10) presence of lesion >50% in the left main coronary artery. Participants were recruited sequentially and randomly assigned in a 1:2 ratio to receive a DES or BMS, according to a computer-generated list of random numbers (Program R 2.11). The DES group consisted of 77 patients who underwent PCI with implantation of a zotarolimus-eluting stent (Endeavor Sprint and Resolute, Medtronic) in single lesions with stenosis of >70% by visual estimation on angiography. The BMS group consisted of 154 patients who underwent PCI with implantation of a BMS in single lesions with stenosis of >70% by visual estimation on angiography. The BMSs used were Integrity (Medtronic), Tsunami (Terumo), and Tango (Microport). In-hospital evaluation included the assessment of clinical variables, angiographic variables, clinical complications, major vascular complications, major cardiac events (death, acute or subacute occlusion, and AMI), and costs. The 1-year clinical follow-up included the assessment of the following parameters: death, AMI, angina, in-stent restenosis (ISR), target lesion revascularization (TLR), late thrombosis, and costs related to re-intervention, if any. Follow-ups were conducted at the HUPE outpatient clinic and at HSL. The aim of PCI was always to obtain a residual lesion <10% on angiography in each treated artery, without signs of dissection or thrombus that would compromise the flow of the vessel. Patients in whom the procedure failed or who required additional stent implantation were excluded from the study. During intervention, any adjuvant medication was administered at the physician’s discretion. After intervention, patients in both groups received dual antiplatelet therapy (DAPT) with aspirin (100 mg/day) and clopidogrel (75 mg/ day), tailoring the duration of DAPT according to the type of stent used, the indication of the physician, and the clinical condition of the patient. Cost-effectiveness Analysis The study population was selected for a clinical trial considering 2 alternatives: PCI with DES or PCI with BMS. An analytical model was constructed by using a decision tree (Figure 1) based on these initial procedures, in a short-term version (1 year). Each avoided ISR was considered for the calculation of effectiveness. The model used probabilistic data from clinical outcomes of a systematic review of randomized clinical trials involving coronary angioplasty with stenting, extracted from the study by Polanczyk et al.  3 The cost of angioplasty was calculated from the perspective of the SUS, using as a reference the amounts reimbursed for previous hospitalizations, with monetary values expressed in Brazilian currency (R$). 3 The cost of BMS was defined as the amount reimbursed by the SUS (R$ 2,034.00). The cost of DES was defined as the average market price of zotarolimus- eluting stents (R$ 3,600.00). ICER was calculated by dividing the difference in costs (hospitalization, complementary tests, percutaneous procedures, and stent price) between the 2 groups by the difference in effectiveness (restenosis-free survival) between the 2 groups. The incremental value suggested by the World Health Organization (WHO) was used as a reference: up to 3 times the value of the GDP per capita, 11  which, according to the Brazilian Institute of Geography and Statistics (IBGE), was R$ 31,587.00 in 2017. 12 81