Pressure wire guide provisional coronary stent implantation

OBJECTIVES: Whether coronary artery lesion successfully dilated by balloon angioplasty should be stented or not is unclear. The purpose of this study is to evaluate the provisional stent implantation method assessing residual ischemia by pressure wire. METHODS: Thirty-one patients with de-novo lesions suitable for stenting were enrolled in a pressure wire guided provisional stent study. The pressure wire was used to assess the fractional flow reserve(FFR) before and after balloon angioplasty. When the FFR after angioplasty was less than 0.75, stent implantation was planned. Patients with lesions consisting of an intermediate stenosis proximal to the target lesion, chronic total occlusion, bypass graft and left main lesion were excluded from the study. Stent implantation was permitted even if the FFR was more than 0.75 when the operator thought stenting was necessary. Medical treatment was given with aspirin 162 mg/day, cilostazol 200 mg/day for 6 months and additional ticlopidine 200 mg/day for a month after stenting the lesion. RESULTS: Target vessel was the left anterior descending coronary artery in 19 lesions, the right coronary artery in 3, and the circumflex coronary artery in 9. Stent implantation was performed in seven (23%) of 31 lesions and the other 24(77%) lesions were treated with only balloon angioplasty. The FFR before intervention was 0.58 +/- 0.16, and improved to 0.87 +/- 0.07 (p < 0.0001). Percentage diameter stenosis before intervention was 70.7 +/- 12.6% and improved to 20.1 +/- 13.3% (p < 0.0001) after intervention. There was no major cardiac event (death, coronary artery bypass grafting, myocardial infarction, stent thrombosis). Six months follow-up angiography was performed in 27 patients (87%). Angiographic restenosis (percentage diameter stenosis > or = 50%) was found in four patients (15%). A new lesion was found in two patients. Target vessel revascularization was performed in six patients (21%). CONCLUSIONS: Lesions successfully dilated by balloon angioplasty with FFR > or = 0.75 do not require stenting.