Failure of Stent Delivery in Lima PCI

Abstract

Back Ground: The internal mammary artery was the most effective conduit for coronary artery bypass surgery and it was associated with significantly better long term patency, survival, and reintervention rates compared to other bypass conduits. The internal mammary artery (IMA) is not immune to atherosclerosis. IMA interventions constitute low percentage out of all coronary interventions. In addition to the tortuous course, the long length of IMA than native coronaries adds procedural difficulties to IMA PCI.Aim: To analyze the acute outcomes of Percutaneous intervention procedures to the internal mammary artery and to found any association with clinical and demographic parameters to the procedural success at a single tertiary care hospital from IndiaMaterials And Methods: This study was a retrospective analysis of post CABG patient who required and undergone the IMA intervention. We collected the clinical, demographic and procedural details of the IMA intervention. We defined as failure of the procedure when the stent could not be delivered to the lesion site through IMA.Results: Total 21 patients were included in this retrospective analysis. Mean age of the study population was 56.1± 9.98 years and 18 patients were male. Twelve (57.1%) patients presented with chronic stable angina and six (28.6%) had Left ventricular dysfunction (LVD) (mild LVD in 5 and one patient had severe LVD). Mean stent diameter was 2.75±0.442 mm and the mean stent length was 17.71 ±5.63 mm. Transient slow flow occurred in 5 patients, but the end result of PCI procedure was good in them. In 4 (19.1%) patients stent could not be delivered. No LIMA dissections were observed. On binary logistic regression, there was no significant difference between successful PCI to the failed PCI with respect to age (p=0.9, z=0.16, OR=0.99, 95%CI=0.83to1.17), male sex (p=0.7, Z=0.34, OR=1.68), type of presentation (p=0.7, Z=0.38, OR=1.60, 95%CI= 0.14 to 17.7), presence of Left ventricular dysfunction (p=0.7, z=0.38, OR=1.60, 95%CI= 0.14 to 16.97) and with pre-dilatation during PCI (p=0.9, z=-0.16, OR=0.99).Conclusion: PCI to the internal mammary artery was associated with 80.95% of success. Not able to deliver the stent to the target lesion was the major problem with LIMA PCI, in addition, to slow or no flow. The success or failure of PCI were not dependent on the age, sex, type of presentation or LV dysfunction.