Table 1.
Demographic and Operative Characteristics of Enrolled Patients
| Characteristics | Total cohort | hFABP POD 2 < post-CPB | hFABP POD 2 > post-CPB |
|---|---|---|---|
| Number of subjects (%) | 1298 | 1090 (90) | 120 (10) |
| Gender (% male) | 82 | 83 | 73* |
| Age (y) | 63 (57–72) | 63 (57–71) | 68 (60–76)† |
| Caucasian race (%) | 84 | 84 | 86 |
| Institution 1 (%) | 74 | 74 | 79 |
| Medical history | |||
| Preoperative LVEF (%) | 55 (45–60) | 55 (45–60) | 55 (45–60) |
| Insulin or noninsulin dependent diabetes (%) | 29 | 29 | 35 |
| Past or present smoker (%) | 70 | 70 | 64 |
| Pulmonary disease (%) | 4.6 | 4.5 | 4.2 |
| Preoperative creatinine (mg/dL) | 1 (0.9–1.2) | 1 (0.9–1.2) | 1.2 (1.0–1.4)† |
| Preoperative hematocrit (%) | 40.4 (37.2–43.6) | 40.5 (37.4–43.7) | 39.4 (36.1–43.1)* |
| Hypertension (%) | 75 | 74 | 83* |
| Hypercholesterolemia (%) | 74 | 75 | 72 |
| Previous myocardial infarction (%) | 44 | 43 | 52 |
| Preoperative medications | |||
| ACE inhibitor (%) | 46 | 46 | 45 |
| β-Blocker (%) | 77 | 78 | 71 |
| Ca++ antagonist (%) | 14 | 13 | 18 |
| Aspirin (%) | 76 | 78 | 66* |
| HMG-CoA reductase inhibitor (%) | 77 | 77 | 74 |
| Surgery | |||
| No. of CABG (%) | |||
| 1 | 2 | 2 | 3 |
| 2 | 13 | 13 | 16 |
| 3 | 45 | 45 | 43 |
| ≥4 | 40 | 40 | 38 |
| CPB duration (min) | 94 (66–118) | 93 (66–117) | 100 (68–125) |
| Aortic cross-clamp duration (min) | 70 (46–90) | 69 (46–89) | 72 (49–95) |
| Biomarkers—preoperative | |||
| CKMB, μg/L (median; IQR) | 0.6 (0.2–1.3) | 0.6 (0.2–1.3) | 0.7 (0.3–1.7)* |
| hFABP, μg/L (median; IQR) | 4.9 (3.5–7.2) | 4.7 (3.5–6.8) | 7.1 (5.2–10.0)† |
| Myoglobin, μg/L (median; IQR) | 61 (46–85) | 59 (45–83) | 79 (61–108)† |
| cTnI, μg/L (median; IQR) | 0 (0–0.04) | 0 (0–0.04) | 0 (0–0.05) |
| Postoperative data | |||
| HLOS (d) | 7 (6–9) | 7 (6–9) | 9 (7–13)† |
| Mortality N (%) up to 5 y | 79 (6) | 51 (4.7) | 22 (18.3)† |
| Ventricular dysfunction (%) | 12 | 11 | 20* |
Each variable is also listed for those patients whose hFABP level peaked at the post-cardiopulmonary bypass (CPB) time point or on postoperative day (POD) 2. Data are shown as percentage for dichotomous variables and median (25th, 75th percentiles for interquartile range [IQR]) for continuous variables. Columns 2 and 3 designate patients who have a decrease in hFABP level between POD2 and immediately post-CPB and those with an elevated hFABP on POD2 compared with immediately after CPB. Biomarker data on 88 additional patients was missing between POD 2 and post CPB.
P values are Kruskal-Wallis 1-way analysis of variance by ranks for continuous data and χ2 distribution or Fisher exact for nominal and ordinal data.
LVEF = left ventricular ejection fraction; ACE = angiotensin converting enzyme; HMG = 3-hydroxy-3-methyl-glutaryl-CoA reductase; CABG = coronary artery bypass graft; CKMB = creatinine kinase MB fraction; hFABP = heart-type fatty acid binding protein; cTnI = cardiac troponin I; CPB = cardiopulmonary bypass; HLOS = hospital length of stay.
P < 0.05,
P < 0.0001 (for hFABP POD 2 > versus < post-CPB).