Epidemiology of infective endocarditis: novel aspects in the twenty-first century

Analysis of Aetiological Agents in Infectious Endocarditis in the Central Military Emergency University Hospital "Dr. Carol Davila" Bucharest

BACKGROUND

Infective endocarditis (IE) is a pathological condition caused by various microbial agents that can lead to severe complications affecting the heart. Accurate diagnosis is crucial for the effective management of patients with IE. Blood culture is the gold standard for identifying the primary infectious agents, which is a key factor in diagnosing IE using the modified Duke criteria.

OBJECTIVE

The main objective of this study was to investigate the distribution of the etiological agents of IE and the most common secondary diagnoses associated with it.

METHOD

A total of 152 patients aged 23-95 years with a diagnosis of IE and proven etiology (through blood cultures or serological tests) were included in this study.

RESULTS

The most common etiological agent identified through blood tests was Enterococcus faecalis, which was detected in 39 patients (23.5%). Staphylococcus aureus was the second most common agent and was identified in 33 patients (19.9%), followed by Staphylococcus epidermidis, which was identified in 12 patients (13.1%). Nine patients (5.8%) had high levels of anti-Coxiella burnetti IgG phase I and II antibodies.

CONCLUSIONS

IE is a leading cause of death in the Department of Infectious Diseases. Early and accurate diagnosis, along with interdisciplinary treatment, can significantly increase the chances of patient survival. Currently, Enterococcus faecalis and Staphylococcus aureus are the dominant etiological agents of IE, highlighting the need to revise protocols for prophylaxis, diagnosis, and initial treatment of this condition.

Healthcare exposures and associated risk of endocarditis after open-heart cardiac valve surgery

BACKGROUND

Infective endocarditis (IE) following cardiac valve surgery is associated with high morbidity and mortality. Data on the impact of iatrogenic healthcare exposures on this risk are sparse. This study aimed to investigate risk factors including healthcare exposures for post open-heart cardiac valve surgery endocarditis (PVE).

METHODS

In this population-linkage cohort study, 23,720 patients who had their first cardiac valve surgery between 2001 and 2017 were identified from an Australian state-wide hospital-admission database and followed-up to 31 December 2018. Risk factors for PVE were identified from multivariable Cox regression analysis and verified using a case-crossover design sensitivity analysis.

RESULTS

In 23,720 study participants (median age 73, 63% male), the cumulative incidence of PVE 15 years after cardiac valve surgery was 7.8% (95% CI 7.3-8.3%). Thirty-seven percent of PVE was healthcare-associated, which included red cell transfusions (16% of healthcare exposures) and coronary angiograms (7%). The risk of PVE was elevated for 90 days after red cell transfusion (HR = 3.4, 95% CI 2.1-5.4), coronary angiogram (HR = 4.0, 95% CI 2.3-7.0), and healthcare exposures in general (HR = 4.0, 95% CI 3.3-4.8) (all p < 0.001). Sensitivity analysis confirmed red cell transfusion (odds ratio [OR] = 3.9, 95% CI 1.8-8.1) and coronary angiogram (OR = 2.6, 95% CI 1.5-4.6) (both p < 0.001) were associated with PVE. Six-month mortality after PVE was 24% and was higher for healthcare-associated PVE than for non-healthcare-associated PVE (HR = 1.3, 95% CI 1.1-1.5, p = 0.002).

CONCLUSIONS

The risk of PVE is significantly higher for 90 days after healthcare exposures and associated with high mortality.

Septic Pulmonary Embolism: A Contemporary Profile

Septic pulmonary embolism (SPE) is a rare clinical entity that is distinct from the classic and more common non-septic thrombotic pulmonary embolism. SPE should be suspected in patients with a systemic acute inflammatory reaction or sepsis who develop signs and symptoms of pulmonary involvement. The diagnosis of SPE depends on the specific radiologic finding of multiple, peripheral, nodular, possibly cavitated lesions. SPE should prompt an immediate search for the primary source of infection; typically, right-sided infective endocarditis, cardiac implantable electronic devices, and septic thrombophlebitis as a complication of bone, skin, and soft tissue infection including Lemierre's syndrome, indwelling catheters, or direct inoculation via injection drug use. Invasive treatment of the infection source may be necessary; in thrombophlebitis, the efficacy and safety of anticoagulation remain undefined. Blood cultures may be negative, particularly among patients with recent antibiotic exposure, and broad-spectrum antimicrobial therapy should be considered. The in-hospital mortality of SPE ranges up to 20% in published case series. While trends in the incidence of SPE are unknown, the opioid epidemic, the growing use of cardiac implantable electronic devices worldwide, and the reported increase in cases of septic thrombophlebitis may be leading to an escalation in SPE cases. We provide a contemporary profile of SPE and propose a clinical management algorithm in patients with suspected or confirmed SPE.

Vacuum-Implemented Removal of Lead Vegetations in Cardiac Device-Related Infective Endocarditis

When approaching infected lead removal in cardiac device-related infective endocarditis (CDRIE), a surgical consideration for large (>20 mm) vegetations is recommended. We report our experience with the removal of large CDRIE vegetations using the AngioVac system, as an alternative to conventional surgery. We retrospectively reviewed all infected lead extractions performed with a prior debulking using the AngioVac system, between October 2016 and April 2022 at our institution. A total of 13 patients presented a mean of 2(1) infected leads after a mean of 5.7(5.7) years from implantation (seven implantable cardioverter-defibrillators, four cardiac resynchronization therapy-defibrillators, and two pacemakers). The AngioVac system was used as a venous−venous bypass in six cases (46.2%), venous−venous ECMO-like circuit (with an oxygenator) in five (38.5%), and venous−arterial ECMO-like circuit in two cases (15.4%). Successful (>70%) aspiration of the vegetations was achieved in 12 patients (92.3%) and an intraoperative complication (cardiac perforation) only occurred in 1 case (7.7%). Subsequent lead extraction was successful in all cases, either manually (38.5%) or using mechanical tools (61.5%). The AngioVac system is a promising effective and safe option for large vegetation debulking in CDRIE. Planning the extracorporeal circuit design may represent the optimal strategy to enhance the tolerability of the procedure and minimize adverse events.