Table 1 Baseline characteristics and perioperative variables of the study population

Age (years)

47.6 ± 12.8

46.3 ± 11.6

48.9 ± 13.8

0.284

Female

48 (42.5)

22 (39.3)

26 (45.6)

0.496

Body mass index (kg/m²)

24.3 ± 3.8

24.8 ± 4.3

23.7 ± 3.3

0.129

Family history of hypertrophic cardiomyopathy

14 (12.4)

4 (7.1)

10 (17.5)

0.093

Family history of sudden death

10 (8.8)

4 (7.1)

6 (10.5)

0.742

History of syncope

35 (31.0)

15 (26.8)

20 (35.1)

0.340

Duration of clinical symptoms (years)

3.0 (1.0, 7.0)

2.0 (1.0, 5.0)

5.0 (2.0, 10.0)

0.031

Comorbidities

Hypertension

48 (42.5)

25 (44.6)

23 (40.4)

0.644

Coronary artery disease

19 (16.8)

10 (17.9)

9 (15.8)

0.769

Pulmonary arterial hypertension

11 (9.7)

4 (7.1)

7 (12.3)

0.357

Diabetes

3 (2.7)

3 (5.4)

0 (0)

0.118

Stoke

4 (3.5)

2 (3.6)

2 (3.5)

1.000

Atrial fibrillation

5 (4.4)

3 (5.4)

2 (3.5)

0.679

Preoperative medications

Aspirin or Clopidogrel

15 (13.3)

7 (12.5)

8 (14)

0.81

Diuretics

6 (5.3)

3 (5.4)

3 (5.3)

1.000

β-blocker

40 (35.4)

17 (30.4)

23 (40.4)

0.267

Statin

3 (2.7)

2 (3.6)

1 (1.8)

1.000

ACEI or ARB

21 (18.6)

11 (19.6)

10 (17.5)

0.774

Laboratory variables

Baseline partial thromboplastin time (s)

11.2 ± 1.5

11.2 ± 1.0

11.1 ± 1.8

0.785

Baseline activated partial thromboplastin time (s)

27.4 ± 5.2

27.2 ± 5.4

27.6 ± 5.1

0.720

Baseline international normalized ratio

1.0 (1.0, 1.1)

1.0 (0.9, 1.0)

1.0 (1.0, 1.1)

0.115

Baseline hemoglobin (g/L)

138.7 ± 22.2

136.1 ± 25.4

141.2 ± 18.4

0.224

Baseline platelet count (10⁹/L)

189.4 ± 63.3

219.6 ± 65.4

159.6 ± 44.7

< 0.001

Nadir platelet count within postoperative four days (10⁹/L)

99.0 (80.0, 137.0)

137.0 (116.5, 165.0)

80.0 (67.0, 87.0)

< 0.001

The absolute decrease from baseline in platelets (10⁹/L)

71.5 (43.8, 110.2)

66.0(29.8,94.5)

81.0 (53.0, 115.0)

0.059

Percentage decrease from baseline in platelets (%)

42.6 (29.0, 52.4)

33.8(17.5,40.0)

50.3 (42.8, 57.3)

< 0.001

Preoperative echocardiography

Left atrium dimension (mm)

45.8 ± 6.4

45.6 ± 6.3

46.1 ± 6.5

0.68

Ejection fraction (%)

61.9 ± 6.0

60.9 ± 5.9

62.8 ± 5.9

0.087

Maximal septal thickness (mm)

24.2 ± 6.3

23.8 ± 5.3

24.7 ± 7.1

0.431

Resting LVOT gradient (mm Hg)

81.0 (44.0, 108.0)

73.0 (35.0, 97.2)

84.0 (53.0, 117.0)

0.098

With systolic anterior motion

93 (82.3)

45 (80.4)

48 (84.2)

0.592

Intraoperative parameters

Anesthesia time (min)

273.1 ± 76.7

253.1 ± 55.0

292.7 ± 89.5

0.006

Surgical time (min)

240.8 ± 70.9

219.6 ± 51.2

261.6 ± 81.2

0.001

Cardiopulmonary bypass time (min)

121.0 (95.0, 153.0)

118.5 (85.8, 143.2)

128.0 (104.0, 172.0)

0.028

Cross-clamp time (min)

70.0 (51.0, 90.0)

69.5 (48.0, 88.0)

74.0 (52.0, 95.0)

0.115

Concomitant other procedure

36 (31.9)

16 (28.6)

20 (35.1)

0.457

Hypotension time (min)

150.0 (115.0, 200.0)

135.0 (113.8, 187.5)

155.0 (115.0, 210.0)

0.157

Intraoperative fluid management

Fluid intake (mL)

1600.0 (1300.0, 2000.0)

1600.0 (1300.0, 1862.0)

1500.0 (1250.0, 2010.0)

0.966

Red blood cells (units)

2.0 (0.0, 2.0)

1.5 (0.0, 2.0)

2.0 (0.0, 2.0)

0.878

Plasma (mL)

0.0 (0.0, 200.0)

0.0 (0.0, 200.0)

0.0 (0.0, 200.0)

0.584

Total output (mL)

980.0 (700.0, 1450.0)

980.0 (700.0, 1500.0)

980.0 (700.0, 1400.0)

0.713

Blood loss (mL)

300.0 (300.0, 400.0)

300.0 (300.0, 400.0)

300.0 (300.0, 400.0)

0.548

Urine volume (mL)

400.0 (200.0, 600.0)

425.0 (200.0, 700.0)

400.0 (300.0, 600.0)

0.441

Blood products within postoperative four days

Red blood cells (units)

0.0 (0.0, 2.5)

0.0 (0.0, 2.0)

2.0 (0.0, 4.0)

0.004

Plasma (mL)

740.0 (370.0, 1090.0)

550.0 (327.5, 970.0)

800.0 (400.0, 1510.0)

0.026

Cryoprecipitate

12 (10.6)

4 (7.1)

8 (14)

0.234

Platelet

5 (4.4)

2 (3.6)

3 (5.3)

1

Blood loss within postoperative four days (mL)

580.0 (370.0, 830.0)

475.0 (303.8, 662.5)

735.0 (475.0, 900.0)

0.001