Author + information
- Received February 24, 1993
- Revision received September 27, 1993
- Accepted November 4, 1993
- Published online March 15, 1994.
- Andrés Iñiguez, MD, PhD, FESC,
- Carlos Macaya, MD, PhD, FESC∗,
- Fernando Alfonso, MD, PhD, FESC,
- Javier Goicolea, MD,
- Rosana Hernandez, MD and
- Pedro Zarco, MD, PhD, FACC
- ↵∗Address for correspondence: Dr. Carlos Macaya, Departamento Cardiopulmonar, Hospital Universitario San Carlos, c/o Profesor Martin Lagos s/n, Madrid 28040, Spain.
Objectives. The purpose of this study was to assess the effects and clinical implications of Palmaz-Schatz stent implantation on coronary blood flow in side branches arising from a stented coronary artery segment.
Background. The occlusion of a side branch is a well defined risk after balloon angioplasty. However, the impact of stenting on the coronary flow in side branches arising within the stented segment is unknown.
Methods. Forty-six stented coronary artery segments with 79 side branches emerging from the stented segment were analyzed. Angiographic studies were performed before angioplasty, after balloon dilation, immediately after stenting and 24 h later. Side branches were classified as follows: type A (≥1 mm in diameter, with ostial narrowing), type B (≥1 mm in diameter, without ostial narrowing), type C (<1 mm in diameter, with ostial narrowing) and type D (< 1 mm in diameter, without ostial narrowing). Quantitative angiography was used to assess the diameter of the side branches.
Results. Stents were implanted electively in lesions with restenosis (41 stents, 89%) or with a suboptimal result after angioplasty (5 stents, 11%). Nine side branches (11%) were type A, 25 (32%) type B, 7 (9%) type C and 38 (48%) type D. At baseline, 68 side branches had Thrombolysis in Myocardial Infarction (TIMI) trial flow grade 3; 10 had grade 2; and 1 had grade 1. Flow worsened (TIMI grade ≥1) in six side branches (8%) after balloon dilation and in four side branches (5%) after stenting. One additional side branch (1%) was occluded at 24 h. Of the 34 side branches ≥1 mm in diameter (mean diameter 1.5 ± 0.3 mm), 2 (6%) had flow impairment after stenting. Three patients experienced transient angina, but no acute myocardial infarction occurred as a result of a side branch occlusion.
Conclusions. Coronary artery stenting does not modify anterograde flow in 90% of side branches. Coronary flow is reduced after stenting in a few branches, but this does not appear to have major clinical relevance.
☆ This work was supported in part by Fondo Investigations Sanitarias (FIS) Grant 91/0733.
- Received February 24, 1993.
- Revision received September 27, 1993.
- Accepted November 4, 1993.