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The presence of a high left ventricular end-diastolic diameter (LVEDD) has been linked to a less favorable outcome in patients undergoing coronary artery bypass grafting (CABG) procedures. However, by taking into consideration the reference of left ventricular size and volume measurements relative to the patient's body surface area (BSA), it has been suggested that the accuracy of the predicting outcomes may be improved.
We propose that BSA weighted LVEDD (bLVEDD) is a more accurate predictor of outcomes in patients undergoing CABG compared to simply using LVEDD alone.
This study was a comprehensive retrospective cohort study that was conducted across multiple medical centers. The inclusion criteria for this study were patients who were admitted for treatment between October 2016 and May 2021. Only elective surgery patients were included in the study, while those undergoing emergency surgery were not considered. All participants in the study received standard care, and their clinical data were collected through the institutional registry in accordance with the guidelines set forth by the Society of Thoracic Surgeons National Adult Cardiac Database. bLVEDD was defined as LVEDD divided by BSA. The primary outcome was in-hospital all-cause mortality (30 days), and the secondary outcomes were postoperative severe adverse events, including use of extracorporeal membrane oxygenation, multiorgan failure, use of intra-aortic balloon pump, postoperative stroke, and postoperative myocardial infarction.
In total, 9474 patients from 5 centers under the Chinese Cardiac Surgery Registry were eligible for analysis. We found that a high LVEDD was a negative factor for male patients’ mortality (odds ratio 1.44,
bLVEDD is an important predictor for male mortality in CABG, removing the bias of BSA and showing a strong capability to accurately predict mortality outcomes.
ClinicalTrials.gov NCT02400125; https://clinicaltrials.gov/ct2/show/NCT02400125
Coronary artery disease causes angina pectoris, myocardial infarction, and ischemic heart failure and thereby contributes significantly to the cardiovascular disease being the leading cause of death worldwide [
Body surface area (BSA) is a simple calculation based on the patients’ height and weight [
Hence, this study investigated the respective effect of LVEDD, BSA, and bLVEDD on early clinical outcomes in patients undergoing CABG by using clinical data from 5 top cardiac centers in China (Beijing Anzhen Hospital, Beijing Tongren Hospital, Beijing Hospital, Peking University People’s Hospital, and Beijing Xuanwu Hospital) under the Chinese Cardiac Surgery Registry database, to reveal (1) the effects of LVEDD on the perioperative prognosis, (2) the relationship between BSA and LVEDD, and (3) whether bLVEDD was associated with perioperative complications and mortality in patients undergoing CABG.
This study was a multicenter retrospective analysis of observational data. A total of 9474 inpatients across the nation (
The study protocol had been approved by the Ethics Committee of Fuwai Hospital (Approval No. 2017-943). The study is registered at ClinicalTrials.gov (NCT02400125). To protect patient privacy, all patient data were deidentified (ie, patient names were replaced with the identification code, and all private patient information was deleted before analysis). The Peking University Clinical Research Institute has created a data committee to evaluate the data quality and supervise data collection. All patients were treated with standard care, and no additional intervention was performed as described previously [
Patient demographics and clinical characteristics were collected and analyzed. This included the patient’s past cardiovascular medical history (peripheral vascular disease, previous cerebrovascular event, previous myocardial infarction [MI], and previous percutaneous coronary intervention and New York Heart Association classification. The last preoperative test results of serum creatinine, total serum cholesterol, serum low-density lipoprotein, blood glucose, and estimated glomerular filtration rate (eGFR) were acquired. The patient’s previous echocardiogram before surgery was also analyzed for LVEDD and left atrial dimension. Intraoperative factors, such as cardiopulmonary bypass time, and aortic cross-clamp time were also analyzed. Variables for concomitant cardiac drugs (ie, nitrate lipid drugs, catecholamines, β-blockers, angiotensin-converting enzyme inhibitor, angiotensin receptor blocker, statins, aspirin, clopidogrel, and ticagrelor) were documented as comprehensively as possible. The primary outcome was in-hospital all-cause mortality (30 days). The secondary outcomes were postoperative severe adverse events, including use of extracorporeal membrane oxygenation, multiorgan failure, use of intra-aortic balloon pump, postoperative stroke, and postoperative MI. The BSA is calculated as follows [
Variables with missing values or outliers warranted interpolation by multiple imputations using the MICE package [
In total, 9474 patients were eligible for the final analysis, of which 7232 (76.34%) were male and 2242 (23.66%) were female. Among female patients, the mean age was 65.26 (SD 7.49) years, and 1032 (46.03%) had an LVEDD of <46 mm. In the male patients, mean age was 61.78 (SD 9.00) years, and 3615 (49.99%) had an LVEDD of <50 mm. Moreover, male patients with an LVEDD of <50 mm had a higher rate of smoking and comorbidity of hyperlipidemia, abnormal serum total cholesterol, and creatinine; a higher risk of previous MI; and a higher score of New York Heart Association (
Patient characteristics according to LVEDDa category.
Characteristics | Gender | |||||||||||||||||
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Female | Male | ||||||||||||||||
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Total | LVEDD<46 | LVEDD≥46 | Total | LVEDD<50 | LVEDD≥50 | ||||||||||||
Total, n | 2242 | 1032 | 1210 | N/Ab | 7232 | 3615 | 3617 | N/A | ||||||||||
Age (years), mean (SD) | 65.26 (7.49) | 65.29 (7.6) | 65.24 (7.39) | .87 | 61.78 (9.00) | 62.12 (8.74) | 61.43 (9.23) | .01 | ||||||||||
BMI (kg/m2), mean (SD) | 25.34 (3.41) | 24.76 (3.26) | 25.82 (3.47) | <.001 | 25.77 (3.06 | 25.38 (3.04) | 26..05 (3.05) | <.001 | ||||||||||
BSAc, mean (SD) | 1.66 (0.14) | 1.63 (0.13) | 1.68 (0.14) | <.001 | 1.87 (0.14) | 1.85 (0.14) | 1.89 (0.14) | <.001 | ||||||||||
Smokingd, n (%) | 193 (8.61) | 85 (8.24) | 108 (8.93) | .56 | 4075 (56.35) | 1953 (54.02) | 2122 (58.67) | <.001 | ||||||||||
Diabetes, n (%) | 1027 (45.81) | 473 (45.83) | 554 (45.79) | .98 | 2708 (37.44) | 1317 (36.43) | 1391 (38.46) | .08 | ||||||||||
Hypertension, n (%) | 1604 (71.54) | 713 (69.09) | 891 (73.64) | .02 | 4401 (60.85) | 2189 (60.55) | 2212 (61.16) | .60 | ||||||||||
Hyperlipidemia, n (%) | 762 (33.99) | 347 (33.62) | 415 (34.3) | .74 | 2457 (33.97) | 1289 (35.66) | 1168 (32.29) | .003 | ||||||||||
Peripheral vascular disease, n (%) | 73 (3.26) | 32 (3.1) | 41 (3.39) | .70 | 252 (3.48) | 120 (3.32) | 132 (3.65) | .44 | ||||||||||
Previous cerebrovascular event, n (%) | 303 (13.51) | 139 (13.47) | 164 (13.55) | .95 | 986 (13.63) | 500 (13.83) | 486 (13.44) | .62 | ||||||||||
Previous MIe, n (%) | 311 (13.87) | 134 (12.98) | 177 (14.63) | <.001 | 1331 (18.40) | 503 (12.81) | 828 (22.89) | <.001 | ||||||||||
Previous PCIf, n (%) | 270 (12.04) | 119 (11.53) | 151 (12.48) | .49 | 1021 (14.12) | 485 (13.42) | 536 (14.82) | .86 | ||||||||||
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NYHA1 | 1801 (80.33) | 831 (80.52) | 970 (80.17) | .29 | 5595 (77.36) | 2717 (75.16) | 2878 (79.57) | <.001 | |||||||||
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NYHA2 | 1311 (58.47) | 623 (60.37) | 688 (56.86) | —h | 4084 (56.47) | 2015 (55.74) | 2069 (57.2) | — | |||||||||
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NYHA3 | 459 (20.47) | 195 (18.9) | 264 (21.82) | — | 1423 (19.68) | 677 (18.73) | 746 (20.62) | — | |||||||||
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NYHA4 | 31 (1.38) | 13 (1.26) | 18 (1.49) | — | 88 (1.22) | 25 (0.69) | 63 (1.74) | — | |||||||||
Serum creatinine (umol/L)i, mean (SD) | 63.58 (20.44) | 63.21 (21.18) | 63.89 (19.79) | .43 | 78.02 (22.23) | 76.77 (20.19) | 79.26 (24.04) | <.001 | ||||||||||
Serum total cholesterol (mmol/L), mean (SD) | 4.23 (1.04) | 4.28 (1.02) | 4.19 (1.05) | .04 | 3.92 (0.97) | 3.95 (0.97) | 3.9 (0.97) | .03 | ||||||||||
Serum low-density lipoprotein, mean (SD) | 2.51 (0.86) | 2.53 (0.85) | 2.49 (0.86) | .19 | 2.34 (0.81) | 2.35 (0.81) | 2.34 (0.81) | .74 | ||||||||||
eGFRj (mL/min/1.73m2), mean (SD) | 99.91 (11.76) | 100.14 (11.7) | 99.71 (11.81) | .38 | 93.88 (10.95) | 94.08 (10.5) | 93.69 (11.39) | .12 | ||||||||||
Blood glucose (mmol/L), mean (SD) | 6.65 (2.02) | 6.57 (1.96) | 6.72 (2.08) | .08 | 6.44 (2.09) | 6.4 (1.92) | 6.48 (2.25) | .11 | ||||||||||
LVEFk, mean (SD) | 61.65 (8.25) | 63.34 (6.81) | 60.22 (9.07) | <.001 | 59.31 (9.08) | 62.38 (6.6) | 56.24 (10.13) | <.001 | ||||||||||
LADl (mm), mean (SD) | 34.83 (7.94) | 34 (7.18) | 35.53 (8.48) | <.001 | 36.52 (7.78) | 35.4 (6.92) | 37.63 (8.4) | <.001 | ||||||||||
LVEDD (mm), mean (SD) | 46.32 (4.96) | 42.28 (2.55) | 49.75 (3.78) | <.001 | 49.99 (5.9) | 45.46 (3.09) | 54.52 (4.38) | <.001 | ||||||||||
Normalized by weight, mean (SD) | 0.75 (0.12) | 0.7 (0.11) | 0.78 (0.13) | <.001 | 0.68v(0.12) | 0.63 (0.1) | 0.73 (0.11) | <.001 | ||||||||||
Normalized by BMI, mean (SD) | 1.86 (0.3) | 1.74 (0.25) | 1.96 (0.3) | <.001 | 1.97 (0.32) | 1.79 (0.24) | 2.09 (0.3) | <.001 | ||||||||||
Normalized by BSA, mean (SD) | 28.05 (3.43) | 26.09 (2.49) | 29.73 (3.23) | <.001 | 26.85 (3.54) | 24.72 (2.45) | 28.99 (3.15) | <.001 | ||||||||||
Nitrate lipid drugsm, n (%) | 547 (24.4) | 232 (22.48) | 315 (26.03) | .51 | 1696 (23.45) | 787 (21.77) | 909 (25.13) | <.001 | ||||||||||
Catecholaminesn, n (%) | 15 (0.67) | 6 (0.58) | 9 (0.74) | .64 | 33 (0.46) | 17 (0.47) | 16 (0.44) | .86 | ||||||||||
β-blockerso, n (%) | 1860 (82.96) | 866 (83.91) | 994 (82.15) | .27 | 6011 (83.12) | 2974 (82.27) | 3037 (83.96) | .05 | ||||||||||
ACEIp or ARBq,r, n (%) | 539 (24.04) | 230 (22.29) | 309 (25.54) | .07 | 1489 (20.59) | 704 (19.47) | 785 (21.7) | .02 | ||||||||||
Statins, n (%) | 1519 (67.75) | 708 (68.6) | 811 (67.02) | .42 | 4942 (68.34) | 2460 (68.05) | 2482 (68.62) | .60 | ||||||||||
Aspirins, n (%) | 672 (29.97) | 295 (28.59) | 377 (31.16) | .19 | 2234 (30.89) | 1016 (28.11) | 1218 (33.67) | <.001 | ||||||||||
Clopidogrel, n (%) | 145 (6.47) | 74 (7.17) | 71 (5.87) | .21 | 547 (7.56) | 276 (7.63) | 271 (7.49) | .82 | ||||||||||
Ticagrelor, n (%) | 86 (3.92) | 46 (4.6) | 40 (3.36) | .14 | 343 (4.84) | 188 (5.37) | 155 (4.33) | .04 |
aLVEDD: left ventricular end-diastolic diameter.
bN/A: not applicable.
cBSA: body surface area.
dSmoking within 2 weeks before surgery.
eMI: myocardial infarction.
fPCI: percutaneous coronary intervention.
gNYHA: New York Heart Association.
hNot available.
iSerum creatinine, serum total cholesterol, serum low-density lipoprotein, eGFR, blood glucose, LVEF, LVEDD, and LAD are the last tests before surgery.
jeGFR: estimated glomerular filtration rate.
kLVEF: left ventricular ejection fraction.
lLAD: left atrial dimension.
mNitrate lipid drugs are administered intravenously 24 hours before surgery.
nCatecholamines are administered intravenously 48 hours before surgery.
oβ-blockers and statins are administered orally 24 hours before surgery.
pACEI: angiotensin-converting enzyme inhibitor.
qARB: angiotensin receptor blocker.
rACEI or ARB are administered orally 48 hours before surgery.
sAspirin, clopidogrel, and ticagrelor are administered orally 5 days before surgery.
As shown in
Patient outcomes according to left ventricular end-diastolic diameter (LVEDD) category.
Characteristics | Gender | ||||||||
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Female | Male | |||||||
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Total | LVEDD<46 | LVEDD≥46 | Total | LVEDD<50 | LVEDD≥50 | |||
Perioperative blood transfusion, n (%) | 1672 (74.58) | 763 (73.93) | 909 (75.12) | .52 | 4740 (65.54) | 2393 (66.2) | 2347 (64.89) | .24 | |
Mechanical ventilation duration (hour), mean (SD) | 26.22 (29.58) | 25.57 (28.2) | 26.77 (30.7) | .34 | 24.43 (26.9) | 23.05 (23.29) | 25.8 (30.03) | <.001 | |
Initial ICUa length of stay (hour), mean (SD) | 37.79 (39.99) | 36.5 (38.19) | 38.89 (41.45) | .16 | 36.45 (39.83) | 32.9 (33.39) | 39.99 (45.08) | <.001 | |
Perioperative blood loss (ml), mean (SD) | 915.1 (809.39) | 899.53 (809.24) | 928.38 (809.62) | .40 | 1087.39 (900.03) | 1081.72 (929.07) | 1093.05 (870.12) | .59 | |
Serum creatinineb (umol/L), mean (SD) | 78.45 (43.49) | 77.08 (45.72) | 79.62 (41.48) | .17 | 91.7 (40.37) | 89.9 (38.2) | 93.51 (42.37) | <.001 | |
eGFRc (mL/min/1.73m2), mean (SD) | 105.15 (34.46) | 107.53 (34.24) | 103.12 (34.53) | .003 | 87.6 (28.3) | 88.64 (27.82) | 86.55 (28.74) | .002 | |
AKId, n (%) | 313 (13.96) | 136 (13.18) | 177 (14.63) | .32 | 715 (9.89) | 348 (9.63) | 367 (10.15) | .46 | |
Use of IAPBe, n (%) | 155 (6.91) | 65 (6.3) | 90 (7.44) | .29 | 522 (7.22) | 208 (5.75) | 314 (8.68) | <.001 | |
Use of ECMOf, n (%) | 18 (0.8) | 9 (0.87) | 9 (0.74) | .73 | 53 (0.73) | 28 (0.77) | 25 (0.69) | .67 | |
Multiorgan failure, n (%) | 31 (1.38) | 12 (1.16) | 19 (1.57) | .41 | 64 (0.88) | 25 (0.69) | 39 (1.08) | .08 | |
Reoperation, n (%) | 49 (2.19) | 24 (2.33) | 25 (2.07) | .90 | 151 (2.09) | 73 (2.02) | 78 (2.16) | .58 | |
Postoperative MIg, n (%) | 10 (0.45) | 4 (0.39) | 6 (0.5) | .70 | 64 (0.88) | 29 (0.8) | 35 (0.97) | .45 | |
Postoperative stroke, n (%) | 33 (1.47) | 14 (1.36) | 19 (1.57) | .68 | 64 (0.88) | 30 (0.83) | 34 (0.94) | .62 | |
Reintubation, n (%) | 21 (0.94) | 9 (0.87) | 12 (0.99) | .77 | 77 (1.06) | 22 (0.61) | 55 (1.52) | <.001 | |
Re-enter ICU, n (%) | 45 (2.01) | 16 (1.55) | 29 (2.4) | .15 | 118 (1.63) | 56 (1.55) | 62 (1.71) | .58 | |
Dead, n (%) | 54 (2.41) | 23 (2.23) | 31 (2.56) | .61 | 107 (1.48) | 33 (0.91) | 74 (2.05) | <.001 |
aICU: intensive care unit.
bSerum creatinine is the maximum serum creatinine after surgery.
ceGFR: estimated glomerular filtration rate. This is the minimum eGFR after surgery.
dAKI: acute kidney injury.
eIAPB: intra-aortic balloon pump.
fECMO: extracorporeal membrane oxygenation.
gMI: myocardial infarction.
Adjusted and unadjusted logistic regression model of the association between body surface area weighted left ventricular end-diastolic diameter (bLVEDD) and prognosis of male patientsa.
Variables | Secondary outcomes | Mortality | |||||||||||||||||||||||
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Univariate | Multivariate | AUCb | Univariate | Multivariate | AUC | |||||||||||||||||||
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ORc | OR |
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OR | OR |
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Numerical bLVEDD | 1.13 (1.12~1.15) | <.001 | 1.12 (1.1~1.13) | <.001 | 0.61 | 1.21 (1.18~1.24) | <.001 | 1.18 (1.15~1.21) | <.001 | 0.71 | ||||||||||||||
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Categorized bLVEDD | 1.76 (1.66~1.86) | <.001 | 1.64 (1.55~1.73) | <.001 | 0.59 | 3.08 (2.69~3.53) | <.001 | 2.7 (2.36~3.1) | <.001 | 0.71 | ||||||||||||||
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<22.5 | 0.73 (0.57~0.92) | .17 | 0.65 (0.51~0.82) | 0.07 | N/Ae | 0 (0~0) | .98 | 0 (0~0) | .98 | N/A | ||||||||||||||
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(22.5, 26) | 1 | N/A | 1 | N/A | N/A | 1 | N/A | 1 | N/A | N/A | ||||||||||||||
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(26, 31.5) | 1.39 (1.26~1.53) | <.001 | 1.32 (1.19~1.45) | <.001 | N/A | 2.7 (2.07~3.52) | <.001 | 2.44 (1.87~3.19) | <.001 | N/A | ||||||||||||||
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(31.5, infinity) | 3.6 (3.2~4.06) | <.001 | 3 (2.65~3.39) | <.001 | N/A | 8.63 (6.52~11.43) | <.001 | 6.54 (4.9~8.73) | <.001 | N/A | ||||||||||||||
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Numerical LVEDD | 1.07 (1.06~1.07) | <.001 | 1.06 (1.05~1.07) | <.001 | 0.59 | 1.1 (1.09~1.12) | <.001 | 1.09 (1.08~1.11) | <.001 | 0.65 | ||||||||||||||
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Categorized LVEDD | 1.22 (1.18~1.26) | <.001 | 1.19 (1.16~1.23) | <.001 | 0.58 | 1.48 (1.36~1.6) | <.001 | 1.44 (1.33~1.56) | <.001 | 0.64 | ||||||||||||||
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<45 | 1 | N/A | 1 | N/A | N/A | 1 | N/A | 1 | N/A | N/A | ||||||||||||||
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(45, 48) | 1.18 (1.01~1.39) | .30 | 1.32 (1.12~1.55) | .09 | N/A | 1.93 (1.19~3.13) | .18 | 2.33 (1.43~3.79) | .08 | N/A | ||||||||||||||
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(48, 51) | 1.17 (0.98~1.38) | .37 | 1.25 (1.05~1.49) | .2 | N/A | 2.03 (1.23~3.35) | .16 | 2.3 (1.39~3.8) | .10 | N/A | ||||||||||||||
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(51, 54) | 1.24 (1.07~1.44) | .15 | 1.37 (1.18~1.6) | .04 | N/A | 2.33 (1.47~3.68) | .07 | 2.85 (1.8~4.53) | .02 | N/A | ||||||||||||||
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(54, infinity) | 2.29 (1.99~2.64) | <.001 | 2.23 (1.93~2.58) | <.001 | N/A | 5.45 (3.53~8.41) | <.001 | 5.58 (3.61~8.64) | <.001 | N/A | ||||||||||||||
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Numerical BSA | 0.3 (0.23~0.41) | <.001 | 0.36 (0.27~0.49) | <.001 | 0.54 | 0.07 (0.04~0.14) | <.001 | 0.11 (0.06~0.23) | <.001 | 0.61 | ||||||||||||||
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Categorized BSA | 0.88 (0.85~0.91) | <.001 | 0.9 (0.87~0.93) | .002 | 0.54 | 0.72 (0.67~0.77) | <.001 | 0.76 (0.7~0.82) | <.001 | 0.62 | ||||||||||||||
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<1.75 | 1 | N/A | 1 | N/A | N/A | 1 | N/A | 1 | N/A | N/A | ||||||||||||||
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(1.75, 1.83) | 0.75 (0.64~0.87) | .06 | 0.75 (0.64~0.88) | .06 | N/A | 0.68 (0.5~0.92) | .20 | 0.7 (0.52~0.96) | .25 | N/A | ||||||||||||||
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(1.83, 1.91) | 0.67 (0.58~0.77) | <.001 | 0.68 (0.58~0.79) | .01 | N/A | 0.54 (0.4~0.73) | .04 | 0.57 (0.42~0.78) | .07 | N/A | ||||||||||||||
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(1.91, 1.99) | 0.6 (0.52~0.7) | <.001 | 0.63 (0.54~0.73) | .003 | N/A | 0.35 (0.25~0.48) | <.001 | 0.39 (0.28~0.55) | <.001 | N/A | ||||||||||||||
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(1.99, infinity) | 0.56 (0.48~0.65) | <.001 | 0.6 (0.52~0.71) | <.001 | N/A | 0.26 (0.19~0.37) | <.001 | 0.33 (0.23~0.47) | <.001 | N/A |
aAge, gender, smoking within 2 weeks before surgery, diabetes, hypertension, hyperlipidemia, last test of serum creatinine before surgery, last test of serum total cholesterol before surgery, last test of serum low-density lipoprotein before surgery, last test of blood glucose before surgery, use of cardiopulmonary bypass, preoperative estimated glomerular filtration rate, and previous cerebrovascular events were used for the multivariate regression. bLVEDD was categorized into 4 groups based on a weight of tree-like segmentation binning.
bAUC: area under the curve.
cOR: odds ratio.
dbLVEDD is LVEDD divided by BSA.
eN/A: not applicable.
fLVEDD: left ventricular end-diastolic diameter.
gBSA: body surface area.
Generalized additive models of body surface area (BSA), left ventricular end-diastolic diameter (LVEDD), and body surface area weighted left ventricular end-diastolic diameter (bLVEDD) for primary and secondary outcomes. (A-C) Probability of mortality. (D-F) Secondary outcomes using restricted cubic splines.
In our cohort, the mean BSA was 1.66 m2 (SD 0.14 m2) for female and 1.87 m2 (SD 0.14 m2) for male patients, which showed a slightly positive relationship (
Since the LVEDD has not been analyzed together with BSA in patients in CABG previously, we speculated that bLVEDD, defined as LVEDD divided by BSA, could better predict postsurgery prognosis. To identify whether bLVEDD increases the risk of postoperative mortality and secondary outcomes as well as whether it is the better predictor of outcomes, both univariate and multivariate logistic regression analyses were performed. As a result, in male patients, bLVEDD showed a strong association with postsurgery mortality; that is, the risk of mortality (adjusted OR 2.70, 2.39-3.10,
To make bLVEDD more practical for male patients undergoing CABG, a weight of tree-like segmentation was used to binning bLVEDD to a categorical variable. As a result, our data set generated a categorization of (0, 22.5), (22.5, 26), (26, 31.5), (31.5, infinity; adjusted Kolmogorov-Smirnov 0.38,
Segmentation of bLVEDD and its ability to predict clinical outcome in male patients. (A) Supervised tree-like segmentation of bLVEDD; (B) receiver operating characteristics; (C) precision-recall for secondary outcomes; and (D,E) motility. bLVEDD: body surface area weighted left ventricular end-diastolic diameter; BSA: body surface area; LVEDD: left ventricular end-diastolic diameter.
In this multicenter cohort study, we reported the following: (1) a high LVEDD is a negative prognostic factor for both postoperative survival and secondary outcomes in male patients; (2) in male patients, high BSA was significantly associated with mortality and secondary outcomes, while female patients’ BSA is not associated with either mortality or secondary outcomes; (3) bLVEDD showed a strong association with postsurgery mortality; that is, the risk of mortality and secondary outcomes changed in parallel with bLVEDD increasing in male patients, but female patients’ bLVEDD did not reach statistical difference; (4) A bLVEDD of 31.5 is the threshold to categorize male patients undergoing CABG with a high or low risk of mortality.
It is known that severe left ventricular dysfunction is associated with increased mortality in patients undergoing CABG [
Echocardiography is widely used in the diagnosis of cardiac diseases, especially for patients undergoing cardiac surgery. The measurement of the size of the left ventricle should be a part of every echocardiography report, because it provides diagnostic clues and prognostic information and enables the clinician to follow up with patients in respect of disease progression [
There is evidence to suggest gender inequality in CABG [
There are some limitations in this study. First, our study is a retrospective cohort study. The data collection of patients in the past is limited, the preoperative activity tolerance of patients is difficult to obtain, the follow-up time was long, and the rate of loss to follow-up was high. Second, intractable heart failure and atrial fibrillation are also common complications after CABG, but they were not included in this study because they were difficult to record accurately during follow-up. Third, BSA is an empirical formula based on weight and height and cannot directly give the true numerical value of the human surface. Especially in this context, BSA is confounded with age, gender, race, etc; thus, a further study is needed to study the factors that have collinearity with BSA.
The bLVEDD is an important predictor for male mortality in CABG, removing the bias of BSA and showing a strong capability to accurately predict mortality outcomes. In predicting perioperative outcomes of CABG, it is important to comprehensively consider the risk factor of left ventricular enlargement and normalize LVEDD by BSA to eliminate bias in male patients. This research highlights significant benefits for enhancing the treatment standards of cardiac surgery and increasing the survival rate of patients following CABG.
Regional distribution of enrolled patients.
Adjusted and unadjusted logistic regression model of the association between body surface area weighted left ventricular end-diastolic diameter (bLVEDD) and prognosis of female patients.
Scatter plot and density distribution of left ventricular end-diastolic diameter (LVEDD) and body surface area (BSA).
Supervised tree-like segmentation of bLVEDD and its evaluation and validation. AUC: Area Under the Curve; F-1: F1 Score; FPR: False Positive Rate; K-S: Kolmogorov-Smirnov; P-R: Precision-Recall; ROC: Receiver Operating Characteristic; TPR: True Positive Rate.
area under the curve
body surface area weighted left ventricular end-diastolic diameter
body surface area
coronary artery bypass grafting
ejection fraction
estimated glomerular filtration rate
left ventricular end-diastolic diameter
myocardial infarction
odds ratio
This work is supported by the Beijing Science and Technology Commission of China (grant D171100002917001 and D171100002917003). The funder had no role in the study design, data collection, data analysis, data interpretation, or writing of the manuscript.
The data sets generated or analyzed during this study are available from the corresponding author on reasonable request.
None declared.