Microvascular Dysfunction in COVID-19 Patients with Acute Coronary Syndrome

Objective

Coronavirus disease 2019 (COVID-19) is considered to deteriorate endothelial function through hyperinflammation. We aimed to investigate microvascular dysfunction using the angiographic parameters thrombolysis in myocardial infarction frame count (TFC) and myocardial blush grade (MBG), in COVID-19 patients with acute coronary syndrome (ACS).

Methods

One hundred and sixty-five patients presented with ACS (62.4% ST elevated myocardial infarction) and underwent percutaneous coronary intervention between March 1 and June 30, 2020, were enrolled in the study. The polymerase chain reaction test was performed in case of suggestive symptoms or typical computerized tomography findings.

Results

Twenty-six patients (15.7%) were tested positive for COVID-19. Significantly higher values were observed in TFC in patients with COVID-19 (p<0.001), whereas COVID-19 patients had significantly lower MBGs (Grade 0 and 1) (p<0.001). Peak troponin-I value was also higher in the COVID-19 group (27335 vs. 15959 ng/dL, p=0.006). Mortality risk was higher in COVID-19 patients (38.4% vs. 7.2%, p<0.001). TFC and ejection fraction may predict in-hospital mortality among COVID-19 patients with ACS according to logistic regression results. In correlation analysis, TFC correlated positively with C-reactive protein (r=0.340, p<0.001) and peak troponin-I value (r=0.369, p<0.001).

Conclusion

COVID-19 is associated with slow coronary flow and microvascular impairment in ACS.

Systemic and local factors associated with reduced thrombolysis in myocardial infarction flow in ST-segment elevation myocardial infarction patients with plaque erosion detected by intravascular optical coherence tomography

Local factors of plaque rupture (e.g. lipid burden) are related to preprocedural thrombolysis in myocardial infarction (TIMI) flow grade during primary percutaneous coronary intervention (PCI). However, the pathological mechanism differs between plaque erosion and rupture. We aimed to identify the factors associated with reduced TIMI flow in plaque erosion. A total of 329 ST-segment elevation myocardial infarction (STEMI) patients with optical coherence tomography (OCT) identified plaque erosion were divided into 2 groups by preprocedural TIMI flow grade [TIMI 0-1 group (n = 219) and TIMI 2-3 group (n = 110)]. Patients in TIMI 0-1 group were older (age > 50 years, 68.5% vs. 51.8%, P = 0.003), and had more diabetes mellitus (18.3% vs. 8.2%, P = 0.015). Plaque erosion with TIMI flow 0-1 was less frequently located in the left anterior descending artery (LAD, 58.4% vs. 72.7%, P = 0.011), but more frequently located in the right coronary artery (RCA, 34.2% vs. 7.3%, P = 0.001) than those with TIMI flow 2-3. TIMI 0-1 group had more lipid plaques (53.9% vs. 41.8%, P = 0.039), macrophage accumulation (59.8% vs. 41.8%, P = 0.002), and calcification (34.2% vs. 21.8%, P = 0.020). In the multivariable analysis, age > 50 years, diabetes mellitus, RCA location, and macrophage accumulation were the independent predictors of reduced TIMI flow grade in STEMI patients with plaque erosion. Systemic factors (older age and diabetes mellitus) and local factors (RCA location and macrophage accumulation) were independently associated with reduced coronary flow in STEMI patients with plaque erosion. CLINICAL TRIAL REGISTRATION : ClinicalTrials.gov NCT03084991 May 17, 2017 (retrospectively registered).