1. Introduction
Infective endocarditis (IE) is a complex and heterogeneous disease with an estimated incidence of 13.8 cases per 100,000 individuals [1, 2]. Despite changes in etiological, microbiological, and epidemiological factors, in-hospital mortality remains around 15%–40% [3, 4].
Surgery is indicated in more than 50% of patients with IE [1, 5]. The surgical benefit, even in high-risk patients, is significant in terms of reducing morbidity and mortality. Although clinical guidelines establish the main indications for surgery, in routine practice, this decision is much more complex and requires an individualized evaluation for each patient [1, 5].
The main goal of this study is to present a detailed account of our experience in the surgical treatment of left-sided valvular IE.
2. Materials and Methods
A retrospective analysis was performed on our database of patients who underwent surgery for IE with left-sided valvular involvement from March 2006 to August 2023.
Baseline, intraoperative, and postoperative characteristics were analyzed. Hospital mortality was defined as death during the hospital stay or within the first 30 days after surgery. Mortality during follow-up was assessed by cross-referencing our database with the National Death Index (INDEF). Emergency surgery was defined as surgery performed before the start of the next working day, urgent surgery as that performed within 72 h of the indication, and scheduled surgery as that performed during the same admission that prompted the indication [6]. Relapse was defined as the recurrence of endocarditis by the same microorganism within the first 6 months after the initial episode, and reinfection as caused by a different microorganism or the same species more than 6 months after treatment of the initial episode [7].
Periannular complications were defined as the evidence of abscess, vegetations, perforations or ruptures, pseudoaneurysm, fistulas, or prosthetic dehiscence [1].
Preoperative cardiogenic shock was defined by the American Heart Association as the state in which ineffective cardiac output caused by a primary cardiac disorder results in clinical and biochemical manifestations of inadequate tissue perfusion [8]. Postoperative low output syndrome is characterized by an inadequate cardiac pump function resulting in reduced oxygen delivery and tissue hypoxia. It is a symptomatic state that ranges from mild myocardial stunning to severe cardiogenic shock with the need for vasoactive support or mechanical ventricular assistance [9].
The study was approved by the hospital’s Ethics Committee, and written informed consent was obtained from all participating patients.
2.1. Statistical Analysis
The Shapiro–Wilk normality test was applied to all continuous variables, which were expressed as mean and standard deviation or median and interquartile range (IQR) depending on the normality of the distribution. Categorical variables were expressed as absolute and relative frequency (%).
A fine-gray competitive risk regression model was used with recurrences and death as competing events. The regression model was estimated from the cumulative incidence function of recurrences. Variables with a p-value < 0.2 in the univariable analysis were included in the multivariable analysis.
A logistic regression model was conducted to analyze independent risk variables associated with hospital mortality, and a Cox regression model was used for independent risk variables associated with long-term mortality. Variables with p < 0.2 in the univariable analysis were included in the multivariable analysis along with those considered clinically relevant. The final model was constructed using forward selection and backward elimination techniques. Significance levels for selection and elimination were < 0.05 and ≥ 0.10, respectively. Overall survival was estimated using the Kaplan–Meier method. Differences with a p-value < 0.05 were considered statistically significant. Statistical analysis was performed using Stata 17 (StataCorp 2017, College Station, TX, USA).
3. Results
Between March 2006 and August 2023, 566 patients were diagnosed with IE at our center. Surgery was required for 371 patients (65.6%) during their admission, of which 352 were for left-sided valvular involvement (Figures 1 and 2). Of these, 65.9% (n = 232) were male with a median age of 67.8 years (IQR 57.4–75.9). The main characteristics are summarized in Table 1.
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Table 1 Baseline characteristics.
N = 352 | |
Male sex | 232 (65.9%) |
Age | 67.8 (IQR 57.4–75.9) |
BMI | 26.6 (IQR 24.2–29.8) |
Obesity (BMI > 29) | 31 (9.9%) |
Diabetes | 104 (29.6%) |
Hypertension | 203 (57.7%) |
Dyslipidemia | 175 (50.4%) |
Smoking | |
Current smoker | 46 (13.1%) |
Former smoker | 113 (32.3%) |
COPD | 42 (11.9%) |
Chronic kidney disease KIDGO > 3 | 147 (41.8%) |
Peripheral artery disease | 38 (10.8%) |
Previous stroke | 57 (16.2%) |
Acute previous stroke | 44 (12.5%) |
History of major cardiac surgery | 148 (42.0%) |
Lack of social support | 21 (5.9%) |
Alcohol use disorder | 21 (6.0%) |
IVDA | 8 (2.3%) |
Congenital heart disease | 28 (8.0%) |
Previous valvular heart disease | 144 (40.9%) |
LVEF | |
Mild dysfunction (51%–55%) | 34 (9.7%) |
Moderate dysfunction (21%–30%) | 28 (8.0%) |
Severe dysfunction (< 30%) | 2 (0.6%) |
Severe pulmonary hypertension (> 55 mmHg) | 59 (16.8%) |
The mean EuroSCORE II was 14.5% (SD 15.9), and the mean RISK-E Score was 27.6% (SD 18.6). Prosthetic endocarditis was present in 39.2% (n = 138).
The primary indications for surgery were persistent heart failure despite medical treatment in 36.1% (n = 127), severe valvular insufficiency in 37.8% (n = 133), and vegetations larger than 10 mm in 31.1% (n = 110) (Table 2).
Table 2 Surgical indication.
N = 352 | |
Persistent heart failure | 127 (36.1%) |
Systemic embolization or high embolic risk | 48 (13.7%) |
Uncontrolled infection | |
Local uncontrolled infection | |
Severe valvular insufficiency | 133 (37.8%) |
Vegetations > 10 mm | 110 (31.3%) |
Perforations/ruptures | 57 (16.2%) |
Abscess | 39 (11.1%) |
Pseudoaneurysm | 29 (8.2%) |
Prosthetic dehiscence | 23 (6.5%) |
Fistulas | 6 (1.7%) |
Persistent positive blood cultures | 14 (3.8%) |
In 84.4% (n = 297) of the patients, the causative microorganism was isolated. The most frequent were coagulase-negative Staphylococci in 17.9%, followed by Enterococcus (12.1%), Viridans Streptococci (13.6%), and Staphylococcus aureus (13.6%) (Table 3). An increase in the incidence of IE caused by Staphylococcus aureus was observed in recent years (Figure 3).
Table 3 Causative microorganisms.
N = 352 | |
Coagulase-negative Staphylococcus | 63 (17.9%) |
Enterococcus | 50 (14.2%) |
Streptococcus viridans | 48 (13.6%) |
Staphylococcus aureus | 48 (13.6%) |
Other Streptococci | 27 (7.7%) |
Streptococcus bovis | 21 (6.0%) |
Fungicidal microorganisms | 15 (4.3%) |
Other microorganisms | 8 (2.3%) |
Gram negative bacilli | 7 (2.0%) |
Polymicrobial | 6 (1.7%) |
Anaerobes | 3 (0.9%) |
HACEK organisms | 1 (0.3%) |
Negative cultures | 55 (15.6%) |
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Urgent/emergency surgery was performed in 47.7% (n = 168) of cases (Table 4). The most common form was isolated aortic valve involvement in 43.5% (n = 153).
Table 4 Surgical characteristics.
N = 352 | |
Surgical priority | |
Preferred | 184 (52.3%) |
Urgent | 107 (30.4%) |
Emergent | 61 (17.3%) |
Access | |
Median sternotomy | 338 (96.0%) |
Mini-sternotomy | 13 (3.7%) |
Mini-thoracotomy | 1 (0.3%) |
Location | |
Isolated aortic valve | 153 (43.5%) |
Isolated mitral valve | 94 (26.7%) |
Multivalvular | 105 (29.8%) |
Aortic valve procedures | n = 253 |
Mechanical prostheses | 81 (32.0%) |
Biological prostheses | 172 (68.8%) |
Mitral valve procedures | n = 190 |
Mechanical prostheses | 129 (67.9%) |
Biological prostheses | 52 (27.4%) |
Valve repair | 9 (4.7%) |
Associated procedures | |
Ascended aortic surgery | 31 (16.3%) |
Supracoronary ascending aorta replacement | 4 (1.1%) |
Bentall–Bono procedure | 27 (7.7%) |
Tricuspid surgery | 14 (4.0%) |
Biological prostheses | 1 (0.3%) |
Aneuloplasty | 13 (3.7%) |
Mitro-aortic junction surgery | 20 (5.7%) |
Coronary artery bypass grafting | 15 (4.3%) |
Cardiopulmonary bypass time (minutes) | 100 (IQR 70–137.5) |
Ischemia time (minutes) | 78 (IQR 55–113.5) |
The median ICU length of stay was 3 days (IQR 1–6), and the median hospital stay was 25 days (IQR 13–43).
During the hospital stay, 36.7% (n = 129) of patients experienced AKIN III acute kidney injury, and 23.6% (n = 83) required mechanical ventilation for more than 24 h, of whom 25 patients required a tracheostomy (Table 5). Hospital mortality was 19.0% (n = 67). The main causes of death were septic shock (54.5%) and cardiogenic shock (30.4%) (Figure 4). Age over 69 years and preoperative cardiogenic shock were independent risk factors for hospital mortality (Table 6).
Table 5 Hospital morbidity and mortality.
N = 352 | |
AKIN III acute kidney injury | 129 (36.7%) |
Prolonged endotracheal intubation (> 24 h) | 83 (23.6%) |
Postoperative atrial fibrillation | 66 (18.8%) |
Reoperation for bleeding | 49 (13.9%) |
Postoperative stroke | 20 (5.7%) |
Postoperative myocardial infarction | 1 (0.3%) |
Intrahospital mortality | 67 (19.0%) |
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Table 6 Multivariate logistic regression analysis.
Univariable OR (CI 95%) | p | Multivariable OR (CI 95%) | p | |
Age | ||||
60–69 years | 2.3 (1.0–5.7)∗ | 0.063 | 2.7 (1.0–7.3) | 0.050 |
70–79 years | 3.6 (1.5–8.4) | 0.003 | 4.0 (1.6–10.5) | 0.003 |
> 80 years | 6.0 (2.4–15.3) | 0.001 | 8.7 (3.0–25.5) | 0.001 |
Preoperative cardiogenic shock | 3.2 (1.6–6.4)∗ | 0.001 | 4.0 (1.6–9.9) | 0.003 |
NYHA functional classification | ||||
II | 2.6 (1.0–7.0)∗ | 0.058 | 1.6 (0.6–4.6) | 0.381 |
III | 4.2 (1.6–10.7) | 0.003 | 2.5 (0.9–6.9) | 0.066 |
IV | 5.5 (1.0–14.7) | 0.001 | 2.0 (0.6–6.2) | 0.249 |
Periannular complications | 1.6 (0.4–1.4)∗ | 0.406 | — | — |
Prosthetic endocarditis | 1.1 (0.7–1.9)∗ | 0.630 | — | |
Intervention priority | 0.7 (0.5–1.0)∗ | 0.081 | — | — |
LVEF | ||||
Mild dysfunction (51%–55%) | 2.5 (1.1–5.5)∗ | 0.021 | 2.0 (0.9–4.9) | 0.110 |
Moderate dysfunction (21%–30%) | 2.5 (1.1–5.9) | 0.036 | 2.5 (1.0–6.5) | 0.059 |
Severe dysfunction (< 30%) | 5.3 (0.3–85.6) | 0.234 | 5.4 (0.3–92.8) | 0.249 |
Hypertension | 1.7 (1.1–2.7)∗ | 0.028 | — | — |
Diabetes | 1.3 (1.0–1.6)∗ | 0.021 | — | — |
Sex | 1.0 (0.6–1.8) | 0.964 | — | — |
COPD | 1.9 (0.9–3.8)∗ | 0.097 | — | — |
Peripheral artery disease | 1.6 (0.8–3.6) | 0.217 | — | — |
Causative microorganism | 1.0 (0.9–1.1) | 0.930 | — | — |
Previous major cardiac surgery | 1.1 (0.6–1.8) | 0.820 | — | — |
The median follow-up was 42.6 months (IQR 7.2–97.4). During the follow-up period, 11.7% (n = 41) of patients experienced a recurrence. In 15 patients (4.2%), it was a reinfection, and in 26 patients (7.4%), it was a relapse. The median time to recurrence was 13 months (IQR 1.4%–48.1%).
In the fine-gray competitive risk analysis using death as a competing risk factor for recurrence, being aged between 60 and 69 years was a protective factor against recurrence (p = 0.036), whereas the presence of prosthetic endocarditis increased the risk of recurrence (HR 2.03 [95% CI 1.09–3.79]; p = 0.004) (Table 7). Figure 5 depicts the cumulative incidence of recurrence. The cumulative incidence of recurrence at 1, 5, and 10 years was 4.5%, 8.2%, and 11.7%, respectively.
Table 7 Fine-Gray competing risk model.
Univariable HR (CI 95%) | p | Multivariable HR (CI 95%) | p | |
Age | ||||
60–69 years | 0.47 (0.21–1.09) | 0.081 | 0.41 (0.18–0.94) | 0.036 |
70–79 years | 0.63 (0.29–1.34) | 0.227 | 0.50 (0.21–1.18) | 0.115 |
> 80 years | 0.46 (0.15–1.35) | 0.155 | 0.38 (0.13–1.15) | 0.088 |
Previous major cardiac surgery | 1.63 (0.88–3.03) | 0.121 | 0.85 (0.43–1.71) | 0.656 |
Prosthetic endocarditis | 2.03 (1.09–3.79) | 0.026 | 2.69 (1.38–5.27) | 0.004 |
Concomitant aortic surgery | 1.76 (0.78–3.95) | 0.171 | 1.14 (0.47–2.77) | 0.772 |
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Mortality during follow-up among patients who experienced a recurrence was 34.2% (n = 14), with a higher mortality rate observed in recurrences (40.0%) compared to reinfections (25.0%).
The incidence of valve reintervention for any cause during follow-up was 14.2% (n = 50), of which 6.3% (n = 22) were due to recurrence of endocarditis.
Overall survival at 1 year, 5 years, and 10 years was 75.2%, 66.2%, and 47.1%, respectively (Figure 6). A Cox regression analysis was conducted to identify variables associated with long-term mortality. Age over 60 years, preoperative cardiogenic shock, moderate preoperative left ventricular dysfunction, mitral valve surgery, low postoperative cardiac output, postoperative acute kidney injury AKIN III, and postoperative stroke were identified as variables associated with long-term mortality (Table 8).
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Table 8 Independent risk variables associated with long-term mortality in patients with infective endocarditis.
Univariable HR (CI 95%) | p | Multivariable HR (CI 95%) | p | |
Age | ||||
60–69 years | 3.4 (1.9–6.0)∗ | 0.001 | 3.6 (2.0–6.4) | 0.001 |
70–79 years | 5.1 (2.9–8.9) | 0.001 | 5.3 (3.0–9.4) | 0.001 |
> 80 years | 7.0 (3.9–12.5) | 0.001 | 5.8 (3.1–10.7) | 0.001 |
Preoperative cardiogenic shock | 1.8 (1.1–2.9)∗ | 0.017 | 2.1 (1.2–3.4) | 0.006 |
NYHA functional classification | ||||
II | 2.4 (1.4–4.4)∗ | 0.003 | — | — |
III | 3.5 (2.0–5.9) | 0.001 | ||
IV | 3.0 (1.7–5.6) | 0.001 | ||
Periannular complications | 0.8 (0.6–1.1) | 0.278 | — | — |
Prosthetic endocarditis | 1.0 (0.7–1.5)∗ | 0.776 | — | — |
Intervention priority | 0.7 (0.5–1.0)∗ | 0.081 | — | — |
LVEF | ||||
Mild dysfunction (51%–55%) | 1.8 (1.1–3.1)∗ | 0.019 | 1.2 (0.7–2.1) | 0.419 |
Moderate dysfunction (21%–30%) | 1.7 (0.9–3.1) | 0.085 | 2.0 (1.1–3.8) | 0.032 |
Severe dysfunction (< 30%) | 1.8 (0.2–12.7) | 0.571 | 0.8 (0.1–6.1) | 0.842 |
Hypertension | 1.7 (1.3–2.3)∗ | 0.001 | — | — |
Diabetes | 1.3 (1.1–1.5)∗ | 0.001 | — | — |
Sex | 1.2 (0.9–1.7) | 0.262 | — | — |
COPD | 1.6 (1.0–2.6)∗ | 0.036 | — | — |
Previous stroke | 1.3 (0.8–2.0) | 0.249 | — | — |
Peripheral artery disease | 1.7 (1.0–2.7)∗ | 0.036 | — | — |
Causative microorganisms | 1.0 (0.9–1.1)∗ | 0.140 | — | — |
Previous major cardiac surgery | 1.2 (0.8–1.6) | 0.373 | — | — |
Concomitant aortic surgery | 0.7 (0.4–1.2)∗ | 0.171 | — | — |
Aortic valve surgery | 0.8 (0.5–1.1)∗ | 0.141 | — | — |
Mitral valve surgery | 1.5 (1.1–2.1)∗ | 0.019 | 2.0 (1.3–3.0) | 0.001 |
Tricuspid valve surgery | 2.0 (1.0–4.0)∗ | 0.040 | — | — |
Multivalvular surgery | 1.3 (0.9–1.8)∗ | 0.184 | — | — |
Type of aortic prosthesis | 0.9 (0.8–1.1) | 0.448 | — | — |
Typo of mitral prosthesis | 1.1 (0.9–1.3) | 0.296 | — | — |
Postoperative low output syndrome | 2.7 (1.9–3.9)∗ | 0.001 | 1.5 (1.0–2.2) | 0.044 |
AKIN III acute kidney injury | 3.5 (2.5–4.8)∗ | 0.001 | 2.7 (1.8–3.8) | 0.001 |
Reoperation for bleeding | 1.2 (0.8–1.9) | 0.405 | — | — |
Postoperative stroke | 2.9 (1.9–4.5)∗ | 0.001 | 2.4 (1.5–3.8) | 0.001 |
Postoperative myocardial infarction | 1.5 (0.5–4.6) | 0.525 | — | — |
Postoperative renal replacement | 1.0 (1.0–1.0)∗ | 0.002 | — | — |
Endocarditis recurrence | 0.8 (0.4–1.3)∗ | 0.340 | 0.8 (0.5–1.5) | 0.517 |
Valvular reoperation | 0.5 (0.3–0.9)∗ | 0.025 | — | — |
4. Discussion
IE is a severe and complex disease associated with high morbidity and mortality. Surgical treatment has been shown to improve survival by up to 20% during the first year [10, 11].
In our study, as in other series [12], the incidence was higher in men than in women, and the median age exceeded 65 years. The presence of IE with aortic involvement in our series was 43.5%, with mitral valve involvement at 26.7%, and multivalvular involvement at 29.8%. Most published studies on the subject report a higher proportion of patients with isolated aortic valve involvement [12].
In recent years, there has been an increase in the prevalence of IE associated with implantable cardiac devices and prosthetic endocarditis, accounting for approximately 20%–30% of the total cases. In our series, it was responsible for 39.2% [13, 14].
Intravenous drug use (IVDU) is a significant risk factor for IE, with a notable predilection for the right side of the heart, particularly the tricuspid valve. However, left-sided endocarditis can also occur in IV drug users, though it is less common [1]. In our series of left-sided endocarditis, a 2.3% of the patients were intravenous drug users.
Regarding the microorganisms involved, there has been a shift in the microbiological agents. Currently, Staphylococcus aureus is the most prevalent cause in approximately 30% of cases, followed by Streptococcus and Enterococcus [15–17]. In our patients, the causative microorganism was isolated in 84.4% of cases. Coagulase-negative Staphylococcus have been the most frequent group, accounting for 17.9% of the total. However, focusing on the last 6 years of the study, we observed that Staphylococcus aureus has become the most prevalent microorganism. Generally, in 10%–30% of cases, the causative microorganism is not detected, and the use of prior antimicrobial therapy has been associated with delays in diagnosis and poorer prognosis, with a higher incidence of associated complications [15, 17, 18].
According to clinical practice guidelines, surgical intervention is indicated in three primary contexts: the presence of heart failure, uncontrolled infection, or as a preventive measure against embolic events. However, it is not uncommon to encounter a combination of different factors [1, 19]. The incidence of embolic complications reported in the literature is approximately 20%–25% and is associated with increased mortality [20]. Patients without associated complications and with severe comorbidities who are too high a risk for surgery can often be successfully treated with antibiotics [1].
In our center, the main surgical indication was the presence of uncontrolled local infection and heart failure. Systemic embolization or high embolic risk was present in 13.7%. Currently, surgery is performed in approximately 50%–60% of all patients diagnosed with IE, with the primary goal of removing infected tissue and material, restoring cardiac integrity and function, and eliminating potential sources of emboli.
Several risk scores have been developed for patients with IE since conventional risk scales do not incorporate specific parameters crucial for assessing the risk in patients with IE [2, 21–23]. The RISK-E Score was developed to estimate the surgical risk of in-hospital mortality in patients with active left-sided IE. This risk score considers important variables such as the microorganisms involved, age, the presence of prosthetic endocarditis, preoperative septic or cardiogenic shock, thrombocytopenia, renal failure, or associated periannular complications [24]. In our study, the mean EuroSCORE II was 14.5% (SD 15.9), and the RISK-E Score was 27.6% (SD 18.6).
Regarding the optimal timing of surgical treatment, more and more studies support the benefit of early surgery to reduce morbidity and mortality in selected patients [25, 26]. Currently, most surgical interventions are performed on a preferential basis, which is within 3–5 days after diagnosis. Delaying surgery until the completion of antibiotic therapy has been associated with a higher incidence of death, hospitalization, embolic events, and recurrence of endocarditis [27–29]. In our study, 47.7% of patients underwent urgent/emergency surgery.
Regarding surgical treatment, in 63.6% of procedures, a biological prosthesis was implanted, in 59.7%, a mechanical prosthesis was used, and in 5.7%, surgery involved reconstruction of the mitral-aortic junction. Valve repair was performed in nine patients with mitral involvement. For decades, mitral valve replacement with a prosthesis has been the surgical treatment of choice for patients with IE. However, more recently, mitral valve repair has become popular whenever feasible, although the advantages and predictors of successful repair are less established in this context, with the feasibility of repairing infected valves ranging from 33% to 78% in different series [28]. Some studies comparing mitral valve repair and replacement in the context of IE have demonstrated better short- and long-term outcomes for mitral valve repair compared to replacement [30, 31]. The latest meta-analysis published in 2022, which included 3759 patients, found a lower risk of short-term mortality, higher long-term survival rates, and a lower risk of recurrence in patients who underwent mitral valve repair [32].
Hospital mortality in most series remains around 25%, with long-term survival rates between 45% and 70%. There are different factors contributing to the high mortality rate, with the most significant being the delay in diagnosis due to often nonspecific symptoms, which leads to late treatment. Additionally, rapid deterioration caused by valve rupture, regurgitation, heart failure, and the presence of septic emboli further exacerbates the condition [3, 17].
In our series, hospital mortality was 19%. Age and the presence of preoperative cardiogenic shock were identified as independent risk factors for hospital mortality, similar to other published series [22]. Other studies have also demonstrated that female sex and chronic kidney disease requiring dialysis are independent risk factors for hospital mortality [22].
The risk of recurrence of IE is estimated to be between 4% and 22%, and approximately 30% of these patients will require intervention. The microorganism most frequently associated with a higher risk of recurrence is Staphylococcus aureus [33, 34]. In our cohort, the recurrence rate was 11.7% (n = 41), with relapse being more common than reinfection (26 patients vs. 15 patients). In the fine-gray competitive risk analysis conducted, prosthetic endocarditis was an independent risk factor for recurrence, and age under 70 years was a protective risk factor (p < 0.05).
Regarding long-term survival, age over 60 years, preoperative cardiogenic shock, moderate preoperative left ventricular dysfunction, mitral valve surgery, low postoperative cardiac output, postoperative AKIN III acute kidney injury, and postoperative stroke were variables associated with long-term mortality in our series. Our findings like other publications suggest that valve location is critical to access the long-term mortality, with an especially high risk for the group of mitral valve procedures [35]. Additionally, multivalvular surgery, prosthetic endocarditis, and Staphylococcus aureus infections have also been shown to influence long-term survival in other series [36, 37]. In our study, the 1-year, 5-year, and 10-year survival rates were 75.2%, 66.2%, and 47.1%, respectively.
All our patients were evaluated by an “Endocarditis team” formed by cardiac surgeons, cardiologists, imaging specialist, microbiologists, and critical care medicine specialists. Due to the complexity of IE, it is necessary to form a multidisciplinary team to optimize outcomes by developing new tools for early diagnosis and improved treatment modalities [1]. This multidisciplinary approach is crucial not only during hospitalization but also in the outpatient setting to ensure close follow-up, provide patient education, and emphasize preventive measures to avoid relapses [38, 39].
4.1. Limitations
Our results should be interpreted with caution due to several limitations inherent in our study design.
This study was conducted in a single center, which may limit the external validity and generalizability of our findings to other institutions with different patient populations and management protocols. Additionally, the retrospective nature of data collection introduces potential biases, including information and selection biases. Despite adjusting for multiple variables in our multivariable models, residual confounding cannot be ruled out and unmeasured variables may have influenced outcomes. Moreover, the limited number of events in some subgroups may have reduced statistical power, affecting the precision of the hazard ratio estimates.
Our findings reflect the experience of a tertiary care hospital with a dedicated endocarditis team, which may not be representative of smaller centers with limited resources.
5. Conclusions
In patients with IE, surgical intervention is indicated in more than 60% of cases, with the aim of removing infected structures and restoring anatomical and hemodynamic function. Despite this, IE remains a complex condition associated with high in-hospital morbidity and mortality and reduced long-term survival.
- Stroke
- Cerebrovascular accident
- IE
- Infective endocarditis
- COPD
- Chronic obstructive pulmonary disease
- LVEF
- Left ventricular ejection fraction
- HTA
- High blood pressure
- AMI
- Acute myocardial infarction
Nomenclature
Data Availability Statement
The data that support the findings of this study titled “Surgical treatment of left-sided infective endocarditis: 15 years of experience” are available from the corresponding author upon reasonable request. All data and findings presented in the manuscript are accurate and derived from ethical research practices.
Conflicts of Interest
Lourdes Montero Cruces as the corresponding author of this paper, I make the following declarations on behalf of myself and all other coauthors:
- I have received confirmation from all other coauthors that the declarations below are true to the best of their knowledge.
- The manuscript complies with the submission guidelines of the Journal of Cardiac Surgery.
- Any potential conflicts of interest have been disclosed within the manuscript.
Author Contributions
All authors have reviewed and approved the final manuscript and have contributed significantly to the research.
Funding
This work titled “Surgical treatment of left-sided infective endocarditis: 15 years of experience” was supported by Fundación para la Investigación Biomédica Hospital Clínico San Carlos (IdISSC).
1 Delgado V., Ajmone Marsan N., De Waha S. et al., 2023 ESC Guidelines for the Management of Endocarditis, European Heart Journal. (2023) 44, no. 39, 3948–4042, https://doi.org/10.1093/eurheartj/ehad193.
2 Agrawal A., Arockiam D., Jamil Y. et al., Contemporary Risk Models for Infective Endocarditis Surgery: A Narrative Review, Therapeutic Advances in Cardiovascular Disease. (2023) 17, 17539447231193291–18, https://doi.org/10.1177/17539447231193291.
3 Rezar R., Lichtenauer M., Haar M. et al., Infective Endocarditis–A Review of Current Therapy and Future Challenges, Hellenic Journal of Cardiology. (2021) 62, no. 3, 190–200, https://doi.org/10.1016/j.hjc.2020.10.007.
4 Vincent L. and Otto C., Infective Endocarditis: Update on Epidemiology, Outcomes, and Management, Current Cardiology Reports. (2018) 20, no. 10, https://doi.org/10.1007/s11886-018-1043-2, 2-s2.0-85051709849.
5 Baddour L. M., Wilson W. R., Bayer A. S. et al., Infective Endocarditis in Adults: Diagnosis, Antimicrobial Therapy, and Management of Complications: A Scientific Statement for Healthcare Professionals From the American Heart Association, Circulation. (2015) 132, no. 15, 1435–86, https://doi.org/10.1161/cir.0000000000000296, 2-s2.0-84944054071.
6 Gutiérrez M., Castaño R., Hornero F. et al., Criterios de Ordenación Temporal de las Intervenciones Quirúrgicas en Patología Cardiovascular y Endovascular Adquirida. Versión 2022, Cirugía Cardiovascular. (2023) 30, no. 1, 24–33.
7 Chu V. H., Sexton D. J., Cabell C. H. et al., Repeat Infective Endocarditis:Differentiating Relapse from Reinfection, Clinical Infectious Diseases. (2005) 41, no. 3, 406–9, https://doi.org/10.1086/431590, 2-s2.0-22544458516.
8 Van Diepen S., Katz J. N., Albert N. M. et al., Contemporary Management of Cardiogenic Shock: A Scientific Statement From the American Heart Association, Circulation. (2017) 136, no. 16, e232–e268, https://doi.org/10.1161/cir.0000000000000525, 2-s2.0-85031940175.
9 Schoonen A., van Klei W. A., van Wolfswinkel L., and van Loon K., Definitions of Low Cardiac Output Syndrome After Cardiac Surgery and Their Effect on the Incidence of Intraoperative LCOS: A Literature Review and Cohort Study, Frontiers in Cardiovascular Medicine. (2022) 9, https://doi.org/10.3389/fcvm.2022.926957.
10 Elgharably H., Hussain S. T., Shrestha N. K., Blackstone E. H., and Pettersson G. B., Current Hypotheses in Cardiac Surgery: Biofilm in Infective Endocarditis, Seminars in Thoracic and Cardiovascular Surgery. (2016) 28, no. 1, 56–59, https://doi.org/10.1053/j.semtcvs.2015.12.005, 2-s2.0-84956922638.
11 Chu V. H., Park L. P., Athan E. et al., Association Between Surgical Indications, Operative Risk, and Clinical Outcome in Infective Endocarditis a Prospective Study from the International Collaboration on Endocarditis, Circulation. (2015) 131, no. 2, 131–140, https://doi.org/10.1161/circulationaha.114.012461, 2-s2.0-84925285609.
12 Habib G., Erba P. A., Iung B. et al., Clinical Presentation, Aetiology and Outcome of Infective Endocarditis. Results of the ESC-EORP EURO-ENDO (European Infective Endocarditis) Registry: A Prospective Cohort Study, European Heart Journal. (2019) 40, no. 39, 3222–3232B, https://doi.org/10.1093/eurheartj/ehz620, 2-s2.0-85073182903.
13 Berisha B., Ragnarsson S., Olaison L., and Rasmussen M., Microbiological Etiology in Prosthetic Valve Endocarditis: A Nationwide Registry Study, Journal of Internal Medicine. (2022) 292, no. 3, 428–437, https://doi.org/10.1111/joim.13491.
14 Lin A. Y., Saul T., Aldaas O. M. et al., Early Versus Delayed Lead Extraction in Patients With Infected Cardiovascular Implantable Electronic Devices, JACC Clinical Electrophysiology. (2021) 7, no. 6, 755–763, https://doi.org/10.1016/j.jacep.2020.11.003.
15 Sebastian S. A., Co E. L., Mehendale M., Sudan S., Manchanda K., and Khan S., Challenges and Updates in the Diagnosis and Treatment of Infective Endocarditis, Current Problems in Cardiology. (2022) 47, no. 9, 101267–28, https://doi.org/10.1016/j.cpcardiol.2022.101267.
16 Cahill T. and Prendergast B., Infective Endocarditis, The Lancet. (2016) 387, no. 10021, 882–893, https://doi.org/10.1016/s0140-6736(15)00067-7, 2-s2.0-84959487788.
17 Cahill T. J., Baddour L. M., Habib G. et al., Challenges in Infective Endocarditis, Journal of the American College of Cardiology. (2017) 69, no. 3, 325–344, https://doi.org/10.1016/j.jacc.2016.10.066, 2-s2.0-85010007206.
18 Meidrops K., Zuravlova A., Osipovs J. D. et al., Comparison of Outcome Between Blood Culture Positive and Negative Infective Endocarditis Patients Undergoing Cardiac Surgery, Journal of Cardiothoracic Surgery. (2021) 16, no. 1, 147–7, https://doi.org/10.1186/s13019-021-01532-9.
19 Klein M. and Wang A., Infective Endocarditis, Journal of Intensive Care Medicine. (2016) 31, no. 3, 151–163, https://doi.org/10.1177/0885066614554906, 2-s2.0-84956554837.
20 Hu W., Wang X., and Su G., Infective Endocarditis Complicated by Embolic Events: Pathogenesis and Predictors, Clinical Cardiology. (2021) 44, no. 3, 307–315, https://doi.org/10.1002/clc.23554.
21 Fernandez-Felix B., Barca L., Garcia-Esquinas E. et al., Prognostic Models for Mortality After Cardiac Surgery in Patients With Infective Endocarditis: A Systematic Review and Aggregation of Prediction Models, Clinical Microbiology and Infection. (2021) 27, no. 10, 1422–1430, https://doi.org/10.1016/j.cmi.2021.05.051.
22 Jussli-Melchers J., Friedrich A., Mandler A. et al., Risk Factor Analysis for 30-Day Mortality After Surgery for Infective Endocarditis. Thoracic and Cardiovascular Surgery, 2024, https://www-thieme--connect-com.m-husc.a17.csinet.es/products/ejournals/abstract/10.1055/s-0044-1779709.
23 Luo L., Huang S., Liu C. et al., Machine Learning-Based Risk Model for Predicting Early Mortality After Surgery for Infective Endocarditis, Journal of the American Heart Association. (2022) 11, no. 11, https://doi.org/10.1161/jaha.122.025433.
24 Olmos C., Vilacosta I., Habib G. et al., Risk Score for Cardiac Surgery in Active Left-Sided Infective Endocarditis, Heart. (2017) 103, no. 18, 1435–1442, https://doi.org/10.1136/heartjnl-2016-311093, 2-s2.0-85028589929.
25 Nappi F., Spadaccio C., and Moon M., A Management Framework for Left Sided Endocarditis: A Narrative Review, Annals of Translational Medicine. (2020) 8, no. 23, 1627, https://doi.org/10.21037/atm-20-4439.
26 Kang D., Lee S., Kim Y. et al., Long-Term Results of Early Surgery Versus Conventional Treatment for Infective Endocarditis Trial, Korean Circulation Journal. (2016) 46, no. 6, 846–850, https://doi.org/10.4070/kcj.2016.46.6.846, 2-s2.0-84994666638.
27 Iaccarino A., Barbone A., Basciu A. et al., Surgical Challenges in Infective Endocarditis: State of the Art, Journal of Clinical Medicine. (2023) 12, no. 18, https://doi.org/10.3390/jcm12185891.
28 Llah S., Sharif S., Ullah S. et al., Infective Endocarditis Surgery Timing, Cardiovascular Revascularization Medicine. (2024) 58, 16–22, https://doi.org/10.1016/j.carrev.2023.07.007.
29 Liang F., Song B., Liu R., Yang L., Tang H., and Li Y., Optimal Timing for Early Surgery in Infective Endocarditis: A Meta-Analysis, Interactive Cardiovascular and Thoracic Surgery. (2016) 22, no. 3, 336–345, https://doi.org/10.1093/icvts/ivv368, 2-s2.0-84961246890.
30 Feringa H. H., Shaw L. J., Poldermans D. et al., Mitral Valve Repair and Replacement in Endocarditis: A Systematic Review of Literature, The Annals of Thoracic Surgery. (2007) 83, no. 2, 564–570, https://doi.org/10.1016/j.athoracsur.2006.09.023, 2-s2.0-33846395373.
31 Wang A., Gaca J., and Chu V., Management Considerations in Infective Endocarditis: A Review, JAMA, the Journal of the American Medical Association. (2018) 320, no. 1, 72–83, https://doi.org/10.1001/jama.2018.7596, 2-s2.0-85049716124.
32 He K., Song J., Luo H. et al., Valve Replacement or Repair in Native Mitral Valve Infective Endocarditis—Which Is Better? A Meta-Analysis and Systematic Review, Journal of Cardiac Surgery. (2022) 37, no. 4, 1004–1015, https://doi.org/10.1111/jocs.16227.
33 Citro R., Chan K. L., Miglioranza M. H. et al., Clinical Profile and Outcome of Recurrent Infective Endocarditis, Heart. (2022) 108, no. 21, 1729–1737, https://doi.org/10.1136/heartjnl-2021-320652.
34 Freitas-Ferraz A. B., Tirado-Conte G., Vilacosta I. et al., Contemporary Epidemiology and Outcomes in Recurrent Infective Endocarditis, Heart. (2020) 106, no. 8, 596–602, https://doi.org/10.1136/heartjnl-2019-315433, 2-s2.0-85073098769.
35 Østergaard L., Smerup M. H., Iversen K. et al., Differences in Mortality in Patients Undergoing Surgery for Infective Endocarditis According to Age and Valvular Surgery, BMC Infectious Diseases. (2020) 20, no. 1, https://doi.org/10.1186/s12879-020-05422-8.
36 Said S. M., Abdelsattar Z. M., Schaff H. V. et al., Outcomes of Surgery for Infective Endocarditis: A Single-Centre Experience of 801 Patients, European Journal of Cardio-Thoracic Surgery. (2018) 53, no. 2, 435–439, https://doi.org/10.1093/ejcts/ezx341, 2-s2.0-85041514187.
37 Pang P. Y. K., Sin Y. K., Lim C. H. et al., Surgical Management of Infective Endocarditis: An Analysis of Early and Late Outcomes, European Journal of Cardio-Thoracic Surgery. (2015) 47, no. 5, 826–832, https://doi.org/10.1093/ejcts/ezu281, 2-s2.0-84929145267.
38 Hubers S. A., DeSimone D. C., Gersh B. J., and Anavekar N. S., Infective Endocarditis: A Contemporary Review, Mayo Clinic Proceedings. (2020) 95, no. 5, 982–997, https://doi.org/10.1016/j.mayocp.2019.12.008.
39 Rajani R. and Klein J. L., Infective Endocarditis: A Contemporary Update, Clinical Medicine. (2020) 20, no. 1, 31–35, https://doi.org/10.7861/clinmed.cme.20.1.1.
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Abstract
Introduction and Objectives: Infective endocarditis (IE) presents a high mortality rate despite medical and surgical advances. The objective of this study is to describe our experience in the surgical treatment of left‐sided valvular IE.
Methods: A retrospective analysis was performed on patients operated for left‐sided valvular IE from March 2006 to August 2023. Fine‐gray competitive risk regression model was used to analyze recurrence, while logistic regression and Cox regression models were assessed to identify independent variables associated with hospital mortality and long‐term mortality.
Results: Out of 566 patients diagnosed with IE, 352 (62.2%) underwent surgery for left‐sided valvular involvement. Of these patients, 65.9% were male with a median age of 67.8 years. The causative microorganism was isolated in 84.4% of cases. Hospital mortality was 19.0% (n = 67). Age over 69 years and preoperative cardiogenic shock were independent risk factors for hospital mortality. A recurrence of endocarditis was observed in 11.7% (n = 41) of patients (26 relapses and 15 reinfections), with prosthetic endocarditis being an independent risk predictor (HR 2.03 (CI 1.09–3.79); p = 0.004). Survival rates at 1, 5, and 10 years were 75.2%, 66.2%, and 47.1%, respectively. Age over 60 years, preoperative cardiogenic shock, preoperative moderate left ventricular dysfunction, mitral surgery, postoperative low cardiac output, postoperative acute kidney injury AKIN III, and postoperative stroke were independent variables associated with long‐term mortality.
Conclusions: Surgery is indicated in more than 60% of patients with IE. Despite this, IE remains a complex disease associated with high in‐hospital morbidity and mortality and a decrease in long‐term survival.
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Details

1 Department of Cardiovascular Surgery, , Clínico San Carlos Hospital, , Madrid, , Spain
2 Department of Cardiology, , Clínico San Carlos Hospital, , Madrid, , Spain
3 Department of Microbiology, , Clínico San Carlos Hospital, , Madrid, , Spain