Comparison of infective endocarditis in patients with and without previously recognized heart disease

Characteristics of patients with infective endocarditis and no underlying cardiac conditions

BACKGROUND

Infective endocarditis (IE) typically occurs in patients with underlying cardiac conditions (UCC). Little is known about IE in patients without UCC. We aimed to describe the clinical, microbiological and imaging characteristics, management, and in-hospital mortality of IE patients without UCC.

METHODS

We analysed the data of patients with definite IE included in an observatory between 1st January 2009 and 31st December 2019. We described patients without UCC compared to those with UCC.

RESULTS

Of 1502 IE patients, 475 (31.6%) had no UCC. They were younger (median 64.0 [19.0-101.0] vs. 70.0 [18.0-104.0] years, p < .001), more often on chronic haemodialysis (5.5% vs. 2.7%, p = .008), and had more often malignancy (22.5% vs. 17.3%, p = .017), immune deficiency (10.3% vs. 6.4%, p = .008), and an indwelling central venous line (14.5% vs. 7.0%, p < .001). They more often developed cerebral complications (34.7% vs. 27.5%, p = .004) and extracerebral embolism (48.6% vs. 36.1%, p < .001). Causative microorganisms were less often coagulase negative staphylococci (5.9% vs. 10.8%, p = .002) or enterococci (10.3% vs. 15.0%, p = .014) and more often group D streptococci (14.1% vs. 10.0%, p = 0.020). Vegetations were more common (92.8% vs. 77.0%, p < 0.001) and larger (14.0 [1.0-87.0], vs. 12.0 [0.5-60.0] mm, p = 0.002). They had more valve perforation or valve regurgitation (67.4% vs. 53.0%, p < 0.001) and underwent valve surgery more often (53.5% vs. 36.3%, p < 0.001). In-hospital mortality did not significantly differ between groups.

CONCLUSION

Patients with IE and no UCC were younger than those with UCC, had specific comorbidities and portals of entry, and a more severe disease course.

Incidence of infective endocarditis caused by viridans group streptococci in Sweden - effect of cessation of antibiotic prophylaxis in dentistry for risk individuals

Introduction

In October 2012, the Swedish Medical Products Agency published new recommendations for the cessation of prophylactic antibiotics in dentistry for the prevention of infective endocarditis (IE). Previously, 2 g of amoxicillin per os would be administered 1 h before invasive dental procedures to patients with valve prosthesis, complicated heart valve disease, and to those with previous endocarditis.

Objectives

The aim of this study was to evaluate whether the total incidence of IE caused by oral viridans group streptococci (VGS) or IE caused by staphylococci, increased in Sweden after the introduction of the new recommendations.

Methods

The incidence of IE in Sweden before and after October 2012 was calculated and compared using an interrupted time series analysis. Separate analyses were conducted for the total incidence of IE, and IE caused by VGS or Staphylococcus aureus. Cases of IE were identified using the Swedish national registry of IE, which has existed since 1995 and contains data from all Swedish hospital clinics specialising in infectious disease. All cases with hospital admission date from the 1^st of Jan 2008, to the 31^st of Dec 2017 were included. The incidence calculations were corrected for annual changes in population size using data from the Swedish government agency Statistics Sweden.

Results

The results show no statistically significant increase in the slope of the trend line of the total incidence of IE, IE caused by VGS or S. aureus in the Swedish general population after October 2012, compared to before.

Conclusion

The results suggest that the recommended cessation of prophylactic antibiotics for the prevention of IE in dentistry has not led to an increased incidence of IE caused by oral streptococci among the Swedish population.

Infective endocarditis involving an apparently structurally normal valve: new epidemiological trend?

Infective endocarditis (IE) has been increasingly diagnosed in patients without previously detected predisposing heart disease, but its clinical features have yet to be fully determined. A recent single-center study including echocardiographic images and surgical findings investigated the incidence of undiagnosed, clinically silent valvular or congenital heart diseases and healthcare-associated infective endocarditis (HAIE). The study confirmed that a large proportion of patients with IE have no previous history of heart disease. Analysis of underlying disease in these patients showed that undetected mitral valve prolapse was the most common disease, followed by an apparently structurally normal valve. The patients who developed IE of apparently structurally normal valves had different clinical characteristics and worse outcomes. IE involving a structurally normal valve was associated with both nosocomial and non-nosocomial HAIE, whereas community-acquired IE was more frequent than HAIE. The pathophysiologic mechanism involving the development of non-HAIE or community-acquired IE due to predominantly staphylococcal infection in an apparently structurally normal valve is not yet clearly understood. Structurally normal valves are not necessarily free of regurgitation or abnormal turbulence and, given the dynamic nature and fluctuating hemodynamic effects of conditions such as poorly controlled hypertension, end-stage renal disease, and sleep apnea, further investigation is necessary to evaluate the potential role of these diseases in the development of IE. An apparently normal-looking valve is associated with IE development in patients without previously recognized predisposing heart disease, warranting repartition of at-risk groups to achieve better clinical outcomes.

Comparison of clinical features of left-sided infective endocarditis involving previously normal versus previously abnormal valves

Native valve infective endocarditis (IE) in patients with normal valves has increased in the last decades. Whether patients with normal valves present a similar prognosis to those with pathologic valves is unresolved. Our aim is to describe epidemiologic and clinical differences between patients with left-sided IE and normal valves and those with native pathologic valves. We analyzed 945 consecutive episodes of IE, 435 of which involved left-sided nonprosthetic IE. They were classified into 2 groups: episodes in normal valves (normal group, n=173) and episodes in pathologic valves (abnormal group, n=262). Patients in the normal group were younger, Staphylococcus aureus and Streptococcus bovis were more frequently isolated, and vegetations were more frequently found. Heart failure, septic shock, and the need for surgery or death were more common. Multivariate analysis identified the following as factors independently associated with normal valve IE: age<65 years, S bovis, S aureus, heart failure, and vegetation detection. Factors independently associated with in-hospital events included S aureus, periannular complications, heart failure, and septic shock development. In conclusion, compared with patients with abnormal valve IE, patients with IE on normal valves were younger, had a more virulent microbiological profile, developed heart failure and septic shock more frequently, needed more surgical procedures, and had worse prognosis.

Clinical and microbiologic features of multivalvular endocarditis

Multivalvular endocarditis accounts for 15% of all endocarditis. The mechanisms of spread of the infection differs whether endocarditis is only left-sided (involving both the mitral and aortic valves) or bilateral. In left-sided bivalvular endocarditis, it is often a secondary mitral lesion following a primary aortic endocarditis. Multivalvular endocarditis often results in severe and extensive cardiac lesions, well described at echocardiography and frequently responsible for severe heart failure. Patients often need surgery, which consists of radical debridement of all the infected tissue with reconstruction using different types of prostheses; therefore, the surgery may be very complex. The goal should be an early diagnosis of endocarditis to avoid spread of the infection to more than one valve, to improve the prognosis for those patients.

Cerebral ischemia caused by Streptococcus bovis aortic endocarditis: case report

Cerebral ischemic processes associated with infective endocarditis caused by Streptococcus bovis are rare; only 2 cases having been reported. Here we report a case of a 50-year-old man with S. bovis endocarditis who presented signs of frontal, parietal and occipital lobe cerebral ischemia. This is the first case reported in which the presence of hemianopsia preceded the endocarditis diagnosis. Initially, the clinical manifestations suggested a systemic vasculitis. Later, vegetating lesions were identified in the aortic valve and S. bovis grew in blood cultures. Antibiotic use and aortic valve replacement eliminated the infection and ceased thromboembolic events. A video colonoscopy examination revealed no mucosal lesions as a portal of entry in this case, although such lesions have been encountered in up to 70% of reported cases of S. bovis endocarditis.

Ischemic stroke and splenic rupture in a case of Streptococcus bovis endocarditis

A 58-year-old man with an acute stroke suffered from splenic rupture. Streptococcus bovis was found in blood cultures, and gram-negative cocci were found in the infarcted spleen. Hemorrhagic transformation of the stroke occurred. Echocardiography showed aortic endocarditis. Cardiac surgery was not performed because of concern about cerebral bleeding. The patient died due to cerebral rehemorrhage after 3 weeks.

[Risk factors associated with endocarditis without underlying heart disease]

Infective endocarditis (IE) pathogenesis has changed in the last decades and there is an increasing number of patients without predisposing heart condition. The aim of this study is to asses the clinical features of these non-drug addict patients affected with IE without underlying heart disease and to identify the potential risk factors. From 196 cases of IE, 49 (25% of the series) occurred in patients without underlying heart disease. A presumed portal of entry was identified in the majority (26 cases). The most frequent were digestive (6 cases), haemodialysis (6 cases) and central venous catheters (4 cases). Right heart valves were more often affected (29 vs 6%; p < 0.01). The distribution of the causative microorganism showed a higher proportion of Staphylococcus (57 vs 30%). Despite a similar in-hospital complication rate and a similar need of surgery during the active phase, their prognosis is better than in those with underlying heart disease.