Table 1 Clinical characteristics of the training and validation cohorts

sex = male (%)

410 (89.9)

122 (89.1)

288 (90.3)

0.82

age (median [IQR])

62.00 [54.00, 67.00]

61.00 [52.00, 67.00]

63.00 [55.00, 68.00]

0.07

cigarette = yes (%)

284 (62.3)

82 (59.9)

202 (63.3)

0.55

drinking = yes (%)

218 (47.8)

62 (45.3)

156 (48.9)

0.54

diabetes = yes (%)

192 (42.1)

54 (39.4)

138 (43.3)

0.51

hypertension = yes (%)

264 (57.9)

80 (58.4)

184 (57.7)

0.97

hyperlipidemia = yes (%)

46 (10.1)

11 (8.0)

35 (11.0)

0.43

cerebrovascular accident = yes (%)

34 (7.5)

10 (7.3)

24 (7.5)

1.00

myocardial infarction = yes (%)

112 (24.6)

26 (19.0)

86 (27.0)

0.09

Previous PCI = yes (%)

50 (11.0)

11 (8.0)

39 (12.2)

0.25

NYHA ≥ III = yes (%)

142 (31.1)

43 (31.4)

99 (31.0)

1.00

EF (median [IQR])

60.05 [47.95, 67.17]

60.10 [47.30, 66.80]

60.00 [48.00, 67.80]

0.80

LVED (median [IQR])

49.05 [45.27, 53.00]

49.50 [45.50, 53.00]

48.90 [45.10, 52.85]

0.28

LAD (median [IQR])

35.70 [32.10, 39.28]

35.10 [32.50, 39.00]

35.70 [32.05, 39.60]

0.87

NTpro-BNP (mean (SD))

641.53 (977.16)

547.64 (797.59)

681.85 (1043.42)

0.18

Anesthesia duration (median [IQR])

314.00 [284.00, 344.00]

314.00 [290.00, 345.00]

312.00 [284.00, 344.00]

0.56

Last intraoperative blood potassium concentration (median [IQR])

4.10 [3.80, 4.50]

4.10 [3.80, 4.40]

4.10 [3.80, 4.50]

0.55

ICU mechanical ventilation time (median [IQR])

21.50 [19.00, 37.25]

21.00 [19.00, 31.00]

22.00 [19.00, 38.50]

0.22

ICU stay time (median [IQR])

67.00 [44.00, 94.00]

67.00 [44.00, 91.00]

67.00 [43.00, 95.00]

0.82

postoperative drainage volume (median [IQR])

937.50 [585.75, 1381.00]

914.00 [591.00, 1340.00]

965.00 [581.00, 1430.00]

0.88

POAF = yes (%)

101 (22.1)

30 (21.9)

71 (22.3)

1.00