Prevalence, Clinical Characteristics, and In-Hospital Outcomes of patients with Angiographic Acute Total Thrombotic Occlusion presenting as NSTEMI.

E. Toledo-Aleman^a, H. Gonzalez-Pacheco^b, J. Sanchez-Nieto^a, R. Gopar-Nieto ^b, Daniel Sierra-Lara Martínez ^b, MA. Arias-Mendoza^b, D. Araiza Garaygordobil^b.

^a Division of Cardiology. Ignacio Chavez National Heart Institute, Mexico City, Mexico.

^b Coronary Care Unit, Ignacio Chavez National Heart Institute, Mexico City, Mexico.

Background: The current paradigm in the treatment of acute coronary syndromes classifies patients according to the presence of persistent ST-segment elevation as a potential marker of total coronary thrombosis, in whom immediate fibrinolysis or primary PCI is appropriate. However, patients with NSTEMI may present with a total acute thrombotic coronary occlusion and may not be detected by this approach, therefore precluding the benefits of early reperfusion strategies.

Purpose: The aim of the present study is to identify the prevalence of total thrombotic occlusion elicited by coronary angiography in patients with NSTEMI, and to analyze their baseline characteristics and in-hospital mortality.

Methods: a retrospective study including consecutive patients admitted with NSTEMI in a single center over a 15-year period. Patients with coronary angiography were further classified in three groups: patients with a total angiographic coronary thrombotic occlusion (TIMI thrombus V), patients with subtotal coronary thrombus (TIMI thrombus I-IV) and patients without angiographic thrombus. Baseline characteristics and in-hospital outcomes were compared among the three groups.

Results: a total of 4216 of NSTEMI patients were admitted within the study period, of whom 3191 underwent coronary angiography and constituted in the final analytic sample. In 211 patients (6.6%) a TIMI thrombus V was found. Table 1 resumes main characteristics among the three groups. Patients with total thrombotic occlusion were younger, a higher proportion were male, and showed a lower prevalence of major cardiovascular risk factors and previous cardiovascular events. During hospital follow up, 15 (7.1%) patients within the total thrombus group, 14 (4.3%) patients within the partial thrombus group and 112 (4.2%) patients within the no-thrombus group died; no statistically significant differences were noted when comparing total thrombotic occlusion vs. no thrombus (HR 1.69, 95% CI 0.94-3.01, p=0.07) (Figure 2).

Conclusions: In this retrospective study, 6.6% of the patients with NSTEMI presented an acute total thrombotic occlusion in coronary angiography. Patients with total thrombotic occlusion showed a different risk-factor profile and a similar in-hospital mortality when compared with non-total thrombus or no thrombus.

Table 1. Baseline Characteristics according to study groups.

Characteristic	NSTEMI total thrombotic ACO (N=211)	NSTEMI non-total thrombotic ACO (n=329)	NSTEMI non-thrombotic (n=2651)	P
Age, years	59.0	60.0	63	.559
Male sex, n (%)	180 (85.3)	270(82.1)	1994 (75.2%)	.000
Clinical Presentation Systolic Blood Pressure (IQR), mmHg Heart Rate (IQR) beats per minute. Killip-Kimball Class n (%) Class I Class ≥ II	128 (111-145) 75 (65-89) 153 (72.5) 11 (27.5)	130 (120-150) 75 (68-87) 253 (76.9) 76 (23.1)	130 (120-150) 76 (69-89) 1921 (72.5) 730 27.5)	.004 .005 .230
Comorbidities, n (%) Current Smoker Smoking History Dyslipidemia Hypertension Diabetes Mellitus	70(33.2) 69(32.7) 81 (38.4) 101 (47.9) 68 (32.2)	77(23.4) 121 (36.8) 144 (43.8) 197 (59.9) 112 (34)	552(20.8) 957 (36.1) 1229 (46.4) 1767 (66.7) 1135 (42.8)	.000 .580 .064 .000 .000
Medical History Myocardial Infarction Previous PCI Coronary bypass graft Stroke Atrial Fibrillation Known Heart Failure	67(31.8) 34 (16.1) 1 (0.5) 3 (1.4) 5 (2.4) 16 (7.6)	116 (35.3) 66 (20.1) 22 (6.7) 8 (2.4) 16 (4.9) 31 (9.4)	1126 (42.5) 618 (23.3) 196 (7.4) 75 (2.8) 81 (3.1) 367 (13.8)	.001 .029 .001 .455 .166 .004
Previous Medication Aspirin Statin	82 (38.9) 53 (25.1)	139 (42.2) 109 (33.1)	1432 (54) 1148 (43.3)	.000 .000
Electrocardiographic Findings ST segment depression ST segment depression in anterior leads	69 (32.7) 34 (16.1)	98 (29.8) 55 (16.7)	855 (32.3) 404 (15.2)	.649 .754
In-Hospital Outcomes Mortality	15 (7.1)	14 (4.3)	112 (4.3)	.144

ACO, Acute Coronary Occlusion. IQR, interquartile range. PCI, percutaneous coronary intervention.