Quantitative comparison of coronary artery flow and myocardial perfusion in patients with acute myocardial infarction in the presence and absence of recent cocaine use.
BACKGROUND
Numerous factors have been implicated in the pathogenesis of cocaine associated myocardial infarction (CAMI). However, the relative contributions each of these mechanisms provide to the pathogenesis of CAMI have not been well defined. We hypothesized that significant angiographic differences exist between CAMI patients vs thrombotic AMI patients (TAMI) and normal controls.


METHODS
The TIMI Flow Grade, corrected TIMI Frame Count (CTFC), TIMI Myocardial Perfusion Grade (TMPG), presence of triple-vessel disease, stenosis severity, and presence of angiographically apparent thrombus were compared in patients who sustained CAMI to TAMI patients and normal controls.


RESULTS
2495 angiograms were analyzed (CAMI = 57, TAMI = 2403, Controls = 35). Impairment in both epicardial and microvascular flow in patients with CAMI was intermediate between TAMI and controls. Compared to TAMI patients, CAMI patients were less likely to have 3 vessel disease (8.9% vs. 19.1%; p < 0.05), epicardial stenosis was less severe (14.9+/-30.2 vs. 72.6+/-18.6; p < 0.0001), less thrombus was present (6.5% vs. 33.1%; p < 0.001) and TIMI grade 3 flow was observed more frequently (76% vs. 59%). Normal TMPG 3 perfusion was significantly impaired in both CAMI and TAMI patients when compared to controls without AMI (TMPG 3 was 40% and 26.6% vs. 100% respectively; p < 0.001 for both). The majority of patients in both AMI groups had diminished or absent tissue level perfusion (TMPG 0 flow, CAMI 53.9 vs. TAMI 56.8%).


CONCLUSIONS
Both epicardial and microvascular flow is impaired in CAMI. While epicardial flow among CAMI patients is slightly better than TAMI patients, the incidence of little or severely impaired tissue level perfusion is nearly identical.
Weber
Jim Edward
JE
The University of Michigan, Department of Emergency Medicine and Hurley Medical Center, USA.
Hollander
Judd E
JE
Murphy
Sabina A
SA
Braunwald
Eugene
E
Gibson
C Michael
CM
D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D019970:Cocaine-Related Disorders / Q000503:physiopathology*; D003326:Coronary Circulation / Q000187:drug effects / Q000502:physiology*; D003331:Coronary Vessels / Q000187:drug effects / Q000502:physiology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000188:drug therapy / Q000503:physiopathology*; D016032:Randomized Controlled Trials as Topic / Q000379:methods / Q000706:statistics & numerical data; D012307:Risk Factors; D018709:Statistics, Nonparametric