Suboptimal coronary flow after PCI in STEMI patients: clinical implications and predictors

Abstract

Background Even in experienced angioplasty centers, percutaneous coronary intervention (PCI) in the acute setting of ST-elevation myocardial infarctions (STEMI) is associated with a low, but still significant rate of suboptimal coronary flow. Identification of its clinical impact and potential modifiable risk factors is important. Purpose To evaluate the clinical impact of suboptimal coronary flow after PCI in STEMI patients and to access potential predictors of suboptimal coronary flow. Methods We retrospectively evaluated 103 hospitalized patients with acute STEMI who were admitted to our center between 2018 and 2019 and underwent PCI. Coronary flow was accessed using the Thrombolysis in myocardial infarction (TIMI) Flow Grading System. Patients were divided into suboptimal patency of the culprit-vessel, defined as TIMI flow ≤2 (group 1, n=8 (7,8%)) and optimal patency of the culprit-vessel defined as TIMI flow 3 (group 2, n=95 (92,2%)). Glomerular filtration rate (GFR) was calculated using the Modification of Diet in Renal Disease (MDRD) formula. Results Mean age 58,15±12,6 years and 85,4% were males. Seventy-eight patients (75,7%) had history of smoking, 45 (43,7%) dyslipidemia, 20 (19,4%) previous acute coronary syndrome, 18 (17,5%) diabetes, 17 (15,5%) were obese and 4 (3,9%) had chronic kidney disease. The revascularization strategy was primary PCI in 55 (54,4%) patients and fibrinolytic therapy with facilitated PCI in 48 (46,6%) patients. Infarct-related artery was the left anterior descending artery in 45 (45,5%) and multivessel disease was present in 38 (38,0%). Angiographic no-reflow after PCI was 3,0%. Intrahospital cardiovascular death occurred in 4 (3,9%) patients and was significantly associated with suboptimal flow (p=0,036) and there was no association with stent thrombosis. Predictors of suboptimal flow were higher blood urea nitrogen, creatinine and GFR at hospital admission (p=0,017 and p=0,012), peak creatinine (p=0,012) and stent length (p=0,038). Suboptimal flow was associated with higher Zwolle score (p=0,010) and ischemic Paris score (p=0,036). Conclusion Failure to achieve optimal culprit-vessel patency after PCI in STEMI patients, although infrequent, is associated with increased hospital cardiovascular death. Longer stents could be and important modified risk factor. Renal dysfunction is an important comorbidity that should be promptly identified and could be partially improved with medical treatment. Funding Acknowledgement Type of funding sources: None.