Background: Deep sternal wound/mediastinitis is a rare but feared complication in coronary artery bypass grafting (CABG) patients and seems to increase the risk of cardiac death, and is also associated with the risk of early internal mammary artery (IMA) graft obstruction. The pathological mechanism explaining the link between mediastinitis and IMA graft obstruction and the impact on mortality is complex, multifactorial, and not fully investigated. Objectives: Mediastinitis has been associated with increased concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin T (TnT) at mid-term follow-up, representing persistent low-grade myocardial injury and impaired cardiac function. However, whether mediastinitis is associated with all-cause mortality, or whether the association is driven by these cardiac-specific biomarkers (NT-proBNP and TnT), is not investigated. Methods: The present study provides the longest and most complete follow-up data in 82 patients undergoing CABG, including 41 with post-sternotomy mediastinitis. Results: The annualized incidence rate of mediastinitis was 0.14%/year and remained stable at 0.14% throughout the study period. During a mean follow-up of 12.7 ± 3.5 years, a total of 42 deaths occurred (27 [65.9%] in mediastinitis and 15 [36.6%] in non-mediastinitis group, p = 0.008). No association was found between IMA or saphenous vein graft obstruction with all-cause mortality. Mediastinitis was associated with a 1.9-fold increased risk of all-cause mortality. However, in the multivariable-adjusted models, age and higher TnT and NT-proBNP levels, but not mediastinitis per se were associated with all-cause mortality. Conclusions: Mediastinitis after CABG surgery was associated with a poor prognosis during a 15-year follow-up, showing a nearly two-fold higher frequency of all-cause mortality compared with non-mediastinitis group, with the differences in mortality rate occurring primarily after 10 years. The association between mediastinitis and all-cause mortality was modulated by subclinical myocardial damage and stretch, reflected by elevated TnT and NT-proBNP, measured at 2.7-year follow-up, underscoring that these could represent prognostic markers in CABG patients.

1.
Risnes
I
,
Abdelnoor
M
,
Almdahl
SM
,
Svennevig
JL
.
Mediastinitis after coronary artery bypass grafting risk factors and long term survival
.
Ann Thorac Surg
.
2010
;
89
(
5
):
1502
9
.
2.
Risnes
I
,
Abdelnoor
M
,
Ulimoen
G
,
Rynning
SE
,
Veel
T
,
Svennevig
JL
.
Mediastinitis after coronary artery bypass grafting increases the incidence of left internal mammary artery obstruction
.
Int Wound J
.
2014
;
11
(
6
):
594
600
.
3.
Risnes
I
,
Aukrust
P
,
Lundblad
R
,
Rødevand
O
,
Ueland
T
,
Rynning
SE
.
Increased levels of NT-proBNP and troponin T 2 years after coronary artery bypass grafting complicated by mediastinitis
.
Front Cardiovasc Med
.
2023 Feb 7
10
1008825
.
4.
Tocco
MP
,
Costantino
A
,
Ballardini
M
,
D’Andrea
C
,
Masala
M
,
Merico
E
.
Improved results of the vacuum assisted closure and Nitinol clips sternal closure after postoperative deep sternal wound infection
.
Eur J Cardio Thorac Surg
.
2009
;
35
(
5
):
833
8
.
5.
Hämäläinen
E
,
Laurikka
J
,
Huhtala
H
,
Järvinen
O
.
Risk factors for 1-year mortality after postoperative deep sternal wound infection
.
Scand J Surg
.
2023
;
112
(
1
):
41
7
.
6.
Milano
CA
,
Kesler
K
,
Archibald
N
,
Sexton
DJ
,
Jones
RH
.
Mediastinitis after coronary artery bypass graft surgery. Risk factors and long-term survival
.
Circulation
.
1995
;
92
(
8
):
2245
51
.
7.
Perrault
LP
,
Kirkwood
KA
,
Chang
HL
,
Mullen
JC
,
Gulack
BC
,
Argenziano
M
.
A prospective multi-institutional cohort study of mediastinal infections after cardiac operations
.
Ann Thorac Surg
.
2018
;
105
(
2
):
461
8
.
8.
Kaspersen
AE
,
Nielsen
SJ
,
Orrason
AW
,
Petursdottir
A
,
Sigurdsson
MI
,
Jeppsson
A
.
Short- and long-term mortality after deep sternal wound infection following cardiac surgery: experiences from SWEDEHEART
.
Eur J Cardio Thorac Surg
.
2021
;
60
(
2
):
233
41
.
9.
Saeed
S
,
Waje-Andreassen
U
,
Nilsson
PM
.
The association of the metabolic syndrome with target organ damage: focus on the heart, brain, and central arteries
.
Expert Rev Cardiovasc Ther
.
2020
;
18
(
9
):
601
14
.
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