Assessment of no-reflow phenomenon by non-constrast computed tomography in patients with acute myocardial infarction undergoing primary percutaneous coronary angioplasty

Type of funding sources: None.

  Coronary no-reflow phenomenon after primary percutaneous coronary angioplasty (pPCI) is an independent predictor of adverse clinical outcomes after AMI regardless of infarct size. The incidence of no-reflow varies widely depending on the diagnostic methods used.

Showing whether non-contrast CT performed after pPCI might be usefull as a diagnosis of no-reflow phenomenon.

Six STEMI patients (mean age = 68.3 y/o) underwent revascularization by pPCI and stent placement within 6 hours after onset of angina and within less than 90 minutes of door-to-balloon time.  Due to the outbreak of SARS-Cov-2, chest CT scanning was indicated in all patients before coronary unit admission (192 ± 102 mins after pPCI).  

  Three patients with a higher time than the mean angina time and than the mean door-to-ballon time (190 ± 149.3 versus 170 ± 107.5 and 63 ± 6.08 vs 56 ± 11.5, respectively) developed an interventional type of no-reflow phenomenon (Table 1) and CT scanning showed regional myocardial contrast retention related to the culprit coronary artery (Figure 1).  On the other hand, three patients with a lower time than the mean angina time and than the mean door-to-ballon time showed TIMI III flow after pPCI (Table 1) and CT scanning showed no regional myocardial contrast retention (Figure 2). 

Myocardial regional contrast retention, evaluated by non-contrast and non-ECG-gated computed tomography after pPCI, might be usefull for no-reflow diagnosis.

TABLE 1

AGE ANGINA-TIME DOOR-TO-BALLON-TIME  BASAL/cTnT  POST-pPCI/cTnT  CHANGE/cTnT

PTS 68 ± 17y/o 170 ± 107mins 56 ± 11mins 1635 ± 2549ng/L 9621 ± 4586ng/L 588% 

(N = 6)

NO-REFLOW

PATS 65 ± 25y/o 190 ± 149mins 63 ± 6mins 761 ± 837ng/L 11151 ± 2787ng/L 1465%

(N = 3)

TIMI-III FLOW

PTS 72 ± 9y/o 117 ± 76mins 49 ± 12mins 2219 ± 3653ng/L 18091 ± 6148ng/L 364%

(N = 3)