Introduction
Paediatric infective endocarditis has a lower prevalence than in the adult population; however, management strategies are based on adult guidelines. The complexity of paediatric infective endocarditis necessitates multidisciplinary care and often includes both antibiotics and surgery.Reference Carrillo, Duenas and Blaney1,Reference Vicent, Luna and Martínez-Sellés2 The potential for morbidity and mortality in the paediatric population is high; therefore, prompt treatment and adequate visualisation are imperative.Reference Shamszad, Khan and Rossano3,Reference Dodge-Khatami, Dodge-Khatami and Nguyen4 Surgical indications for infective endocarditis include progressive heart failure, perivalvular extension of infection, abscess formation, new onset arrhythmia/heart block, bacteraemia that is not improving with antibiotics, and embolic complications.Reference Carrillo, Duenas and Blaney1 Surgical treatment may be more beneficial if completed soon after diagnosis rather than after the active and acute phases of infection.Reference Shamszad, Khan and Rossano3,Reference Khoo, Buratto and Fricke5 When treated via median sternotomy, patients are at risk for post-operative complications such as deep sternal wound infections.Reference Zukowska and Zukowski6,Reference Dodge-Khatami, Gil-Jaurena and Hörer7 This risk is increased if the patient is actively infected with or is a carrier of Staphylococcus aureus.Reference Zukowska and Zukowski6 Compared to a median sternotomy for mitral valve surgery, a right axillary approach has been associated with a decrease in the risk of deep sternal wound infections.Reference Dodge-Khatami, Gil-Jaurena and Hörer7 It is intuitive that this decreased infection risk should be true for other operations as well such as those for endocarditis.
In addition, minimally invasive paediatric cardiac surgery is gaining popularity due to improved cosmesis, decreased surgical trauma, decreased hospital length of stay, and faster rates of recovery with minimal to no requirement for outpatient cardiac rehabilitation—all while reducing overall morbidity and mortality.Reference Dodge-Khatami, Gil-Jaurena and Hörer7,Reference Dodge-Khatami and Dodge-Khatami8 While thoracotomy approaches in children have been used in simple and even some complex repairs, a right axillary thoracotomy approach for treatment of infective endocarditis has not been described. We report on a previously healthy patient diagnosed with tricuspid valve endocarditis who underwent minimally invasive repair.
Clinical summary
A 7-year-old, 29 kg boy without a history of any genetic syndromes, heart disease, or prior surgery presented to the emergency department with fever (39.3 °C) for 24 hours following 6 days of reduced mobility and pain in his left leg. The patient was admitted to the ICU and ceftriaxone and vancomycin were initiated. The patient remained febrile (39.4–40.5 °C) and tachycardic (130–155 beats per minute) with repeatedly positive blood cultures for methicillin-resistant Staphylococcus aureus. On hospital day three, he developed Janeway lesions, and the following day, echocardiogram showed three vegetations on the tricuspid valve: two on the atrial side (measuring 1 × 0.9 cm and 0.5 × 0.8 cm) and one on the ventricular side (measuring 1.6 cm × 0.8 cm) [Figure 1]. There was mild tricuspid valve regurgitation and normal right ventricular function. On hospital day five, CT angiography showed irregularly shaped nodular lesions suggestive of septic pulmonary emboli. After a multidisciplinary review, surgery was recommended and occurred on the eighth day of admission. Preoperative imaging revealed no evidence of a patent foramen ovale or an atrial septal defect. The patient was placed in left lateral decubitus position, and a vertical right axillary thoracotomy in the fourth intercostal space was performed in a muscle-sparing approach. Cannulation of the aorta, inferior vena cava, and superior vena cava was performed to initiate cardiopulmonary bypass, a right atriotomy was performed, and retraction sutures were placed to improve tricuspid valve visualisation [Figure 2(a)]. A large vegetation on the septal leaflet was resected, debrided, and the area was irrigated with clindamycin and betadine. The resulting defect in the leaflet was repaired with an autologous pericardial patch [Figure 2(b)]. Fluid testing yielded some tricuspid regurgitation, prompting the placement of an anteroseptal commissuroplasty stitch. Following this, there was no obvious tricuspid regurgitation on fluid testing. The atriotomy was closed, and the patient regained normal sinus rhythm prior to being weaned from bypass. Post-repair transesophageal echocardiogram (TEE) demonstrated mild tricuspid regurgitation. Atrial pacing wires were placed, the ribs were reapproximated, and soft tissue closure was completed in layers. The patient returned to the cardiac ICU and was extubated on milrinone; post-operative blood cultures were negative. On post-operative day four, the patient developed a left-sided effusion and developed febrile tachycardia. On post-operative day seven, a CT showed a left pleural effusion and cavitation of the posterior upper lobe segment suggestive of septic emboli. A chest tube was placed and drained 250 cc of exudative fluid positive for Staphylococcus aureus. Tissue plasminogen activator was instilled into the chest tubes to further facilitate exudative drainage. Twelve days after surgery, CT showed resolution of the pleural effusion, and the chest tube was removed. The patient was then discharged on an antibiotic regimen of daptomycin (six weeks) and linezolid (three weeks). The patient was seen six weeks postoperatively in the clinic, where physical examination revealed a well-healing surgical site. Surveillance blood cultures were negative. Follow-up echocardiogram showed mild residual tricuspid regurgitation, no tricuspid stenosis, and normal right ventricular size and systolic function.
Visualisation of vegetation on the septal leaflet of the tricuspid valve as visualised upon preoperative echocardiogram.
(a) Representation of the surgical field through a right axillary thoracotomy approach to visualise the tricuspid valve. (b) Post-operative visualisation of the repaired septal leaflet.
Discussion
Compared to adults, the paediatric population has a lower incidence of minimally invasive cardiac surgery.Reference Dodge-Khatami, Gil-Jaurena and Hörer7,Reference Dodge-Khatami and Dodge-Khatami8 However, techniques for minimally invasive surgery in the adult population have been adopted for congenital heart operations.Reference Alnajar, Chatterjee and Olive9 Within the adult population, minimally invasive techniques have become a commonly utilised approach for surgical treatment of mitral valve infective endocarditis.Reference Barbero, Pocar and Brenna10 These approaches were initially intended to yield cosmetically favourable incisions, but technologic advances have projected this field towards optimising patient care by eliminating post-operative sternal precautions and therefore improving paediatric patients’ quality of life.Reference Dodge-Khatami, Dodge-Khatami and Nguyen4 Additional unfavourable effects of cardiac surgery such as length of hospital stay, cardiac rehabilitation requirements, risk of post-operative complications such as deep sternal wound infections can be mitigated with a right axillary approach as compared to a traditional median sternotomy.Reference Zukowska and Zukowski6,Reference Dodge-Khatami, Gil-Jaurena and Hörer7 Mini sternotomy and thoracotomy techniques have been developed to repair atrial septal defects, ventricular septal defects, patent ductus arteriosus, vascular rings, and other defects.Reference Dodge-Khatami, Gil-Jaurena and Hörer7 Despite the potential benefits of less invasive approaches, these approaches have not hitherto been employed in the surgical treatment of endocarditis in children.
While this patient had a good outcome, it is important to recognise that the axillary thoracotomy approach has some limitations in the presence of endocarditis or other disease that may require reintervention. A sternotomy could have offered the option of widely draining both pleural spaces, with the theoretical goal of sterilising the spaces and preventing empyema formation. However, there was no evidence of pleural effusion preoperatively, and therefore, there was no indication for empiric drainage and sterilisation of the pleural spaces. In cases where empyema is present or suspected in the left pleural space, drainage must be performed separately when performing a right axillary approach for endocarditis. While redo thoracotomy has been widely reported in adult mitral valve surgery, experience with redo thoracotomy for minimally invasive cardiac procedures in children is limited.Reference Suzuki11 We hypothesise that a reintervention via thoracotomy would be possible and that it would likely have a similar safety profile as would a redo sternotomy. Furthermore, because the pericardium was not violated anteriorly and the sternum was never divided, a sternotomy for future cardiac interventions should be considerably less complicated than would be a traditional redo sternotomy. It is important to note that this approach was pursued after careful review of the anatomy and after deeming that repair would likely be accomplished with simple vegetectomy and patch placement. We cannot comment on how feasible more complex repairs would be through this approach, though there were no significant technical challenges encountered. Finally, the senior authors of this manuscript have considerable experience in right axillary thoracotomy approaches for cardiac surgery and would recommend that surgeons wishing to incorporate right axillary thoracotomy into their practice start with less complicated procedures before attempting a valve repair such as this.
Conclusion
This case represents a unique approach to the surgical management of infective tricuspid valve endocarditis in paediatric patients. There are potential advantages of the axillary thoracotomy approach, including cosmesis, the lack of sternal precautions, and decreased risk of sternal wound infections. We hope that this technique may prove to be useful as minimally invasive surgical methods are further integrated into CHD.
Acknowledgements
Illustrations for this article were created by Eo Trueblood and Stream Studios, Philadelphia, PA.
Financial support
This research received no specific grant from any funding agency, commercial, or not-for-profit sectors.
Competing interests
The authors declare none.
Ethical standards
N/A.
