Analysis of surgical versus medical therapy in active complicated native valve infective endocarditis

Bridging Molecular and Clinical Sciences to Achieve the Best Treatment of Enterococcus faecalis Endocarditis

Enterococcus faecalis (E. faecalis) is a commensal bacterium that causes various infections in surgical sites, the urinary tract, and blood. The bacterium is becoming a significant concern because it tends to affect the elderly population, which has a high prevalence of undiagnosed degenerative valvular disease and is often subjected to invasive procedures and implanted medical devices. The bacterium's actions are influenced by specific characteristics like pili activity and biofilm formation. This resistance significantly impedes the effectiveness of numerous antibiotic therapies, particularly in cases of endocarditis. While current guidelines recommend antimicrobial therapy, the emergence of resistant strains has introduced complexity in managing these patients, especially with the increasing use of transcatheter therapies for those who are not suitable for surgery. Presentations of the condition are often varied and associated with generalised symptoms, which may pose a diagnostic challenge. We share our encounter with a case study that concerns an octogenarian who had a TAVI valve and developed endocarditis. We also conducted a literature review to identify the essential treatment algorithms for such cases.

Early versus Delayed Surgery in Patients with Left-Sided Infective Endocarditis and Stroke

BACKGROUND

Timing of surgery remains controversial in patients with infective endocarditis and stroke. Guidelines on infective endocarditis suggest delaying surgery for up to 4 weeks. However, with early heart failure due to progression of the infection or recurrent septic embolism, urgent surgery becomes imperative.

METHODS

Out of 688 patients who were surgically treated for left-sided infective endocarditis, 187 presented with preoperative neurological events. The date of cerebral stroke onset was documented in 147 patients. The patients were stratified according to timing of surgery: 61 in the early group (0-7 days) vs. 86 in the delayed group (>7 days). Postoperative neurological outcome was assessed by the modified Rankin Scale.

RESULTS

Preoperative sepsis was more prevalent in patients with preoperative neurological complications (46.0% vs. 29.5%, p < 0.001). Patients with haemorrhagic stroke were operated on later (19.8% vs. 3.3%, p = 0.003). Postoperative cerebrovascular accidents were comparable between both groups (p = 0.13). Overall, we observed good neurological outcomes (p = 0.80) and a high recovery rate, with only 5% of cases showing neurological deterioration after surgery (p = 0.29). In-hospital mortality and long-term survival were not significantly different in the early and delayed surgery groups (log-rank, p = 0.22).

CONCLUSIONS

Early valve surgery in high-risk patients with infective endocarditis and stroke can be performed safely and is not associated with worse outcomes.

Five-year outcomes following complex reconstructive surgery for infective endocarditis involving the intervalvular fibrous body

OBJECTIVES

Destruction of the intervalvular fibrous body (IFB) due to infective endocarditis (IE) warrants a complex operation involving radical debridement of all infected tissue, followed by double valve replacement (aortic and mitral valve replacement) with patch reconstruction of the IFB. This study assesses the 5-year outcomes in patients undergoing this complex procedure for treatment of double valve IE with IFB involvement.

METHODS

A total of 127 consecutive patients underwent double valve replacement with reconstruction of the IFB for active complex IE between January 1999 and December 2018. Primary outcomes were 3-year and 5-year survival, as well as 5-year freedom from reoperation.

RESULTS

Patients' mean age was 65.3 ± 12.9 years. Preoperative cardiogenic shock and sepsis were present in 17.3% and 18.9%, respectively. The majority of patients (81.3%) had undergone previous cardiac surgery. Overall, 30-day and 90-day mortality rates were 28.3% and 37.0%, respectively. The 3- and 5-year survival rates for all patients were 45.3 ± 5.1% and 41.8 ± 5.8%, and for those who survived the first 90 postoperative days 75.8 ± 6.1% and 70.0 ± 8.0%, respectively. The overall 5-year freedom from reoperation was 85.1 ± 5.7%. Preoperative predictors for 30-day mortality were Staphylococcus aureus [odds ratio (OR) 1.65; P = 0.04] and left ventricular ejection fraction (LVEF) <35% (OR 12.06; P = 0.03), for 90-day mortality acute kidney injury requiring dialysis (OR 6.2; P = 0.02) and LVEF <35% (OR 9.66; P = 0.03) and for long-term mortality cardiogenic shock (hazard ratio 2.46; P = 0.01).

CONCLUSIONS

Double valve replacement with reconstruction of the IFB in patients with complex IE is a challenging operation associated with high morbidity and mortality, particularly in the first 90 days after surgery. Survival and freedom from reoperation rates are acceptable thereafter, particularly considering the severity of disease and complex surgery.

A narrative review of early surgery versus conventional treatment for infective endocarditis: do we have an answer?

The most appropriate strategy and timing for surgery in infective endocarditis (IE) remains an argument of debate. Despite some authors promote the adoption of an early surgical approach (within 48 hours) to limit mortality and complications, no robust randomized trials are available on this argument and the evidence on this subject remain at the "expert opinion" level. Additionally, the different messages promulgated by the American and European guidelines contributed to fuel confusion regarding the relative priority of the surgical over medical therapy in IE. The European Society of Cardiology (ESC) guidelines individuates three level of urgency: emergency surgery, to be performed within 24 hours; urgent surgery, recommended within a few days; elective surgery to be performed after 1-2 weeks of antibiotic therapy. Urgent surgery is recommended for most cases of IE. In the American Heart Association (AHA)'s guidelines define early surgery as "during the initial hospitalization and before completion of a full course of antibiotics." Some of the available evidences showed that are no proven benefits in delaying surgery if a definite diagnosis of IE has been established. However, this argument is controversial across the literature and several factors including the center specific experience can play a role in decision-making. In this review the latest evidences on IE clinical and surgical characteristics along with the current studies on the adoption of an early surgical approach are analyzed to clarify whether enough evidence is available to inform an update of the guidelines.

An aggressive form of Haemophilus parainfluenzae infective endocarditis presenting with limb weakness

We present the case of a 49-year-old man with a bicuspid aortic valve who presented to the emergency department with limb weakness and a fever. Blood tests revealed a fulminant septic process with Haemophilus parainfluenzae bacteraemia, anaemia and thrombocytopenia. Imaging revealed a cervical spinal abscess and discitis causing spinal cord compression, in addition to multiple cerebral septic emboli, pleural effusions and ascites. A transoesophageal echocardiogram (TOE) performed post decompression of his spinal collection showed native aortic valve endocarditis with an associated large aortic root abscess. He underwent successful aortic valve surgery and a 6-week course of antibiotic therapy and made an excellent clinical recovery with no long-term complications from his condition.

Recognition and Treatment of Acute Aortic Regurgitation

Acute aortic regurgitation usually results from infective endocarditis, but is also caused by aortic dissection and trauma to the heart. Most of the left ventricular stroke volume is regurgitated back into the left ventricle; thus, the forward stroke volume to the body and the cardiac output may be severely compromised. An acute increase in left ventricular end-diastolic volume results in a marked increase in left ventricular end-diastolic pressure, and the mitral valve usually closes prematurely. Compensatory tachycardia is the rule and helps to shorten diastole; thus, the time available for aortic regurgitation to occur is reduced, and the cardiac output is often maintained.

On physical examination, there is tachycardia; the peripheral arterial pulse shows a rapid rise, but the systolic pressure is normal; the diastolic pressure is normal or even reduced; and the pulse pressure is often normal. The electrocardiogram (ECG) may be normal except for sinus tachycardia and often for nonspecific ST-T changes. The chest roentgenogram usually shows signs of pulmonary venous hypertension or even pulmonary edema. Echocardiography may show vegetations on the aortic valve, prolapse of an aortic leaflet into the left ventricle, and premature mitral valve closure. Doppler echocardiography is useful in detecting the presence of aortic regurgitation.

In cases of infective endocarditis, the appropriate antibiotic therapy must be given. Aortic regurgitation due to dissection of the aorta is usually an indication for surgery. In patients with severe aortic regurgitation, available medical therapy includes digitalis, diuretics, and vasodilators. When patients respond dramatically to the use of digitalis, diuretics, and arterial dilators, surgical therapy can be delayed until heart failure and infection are controlled and the patient is more stable. If the patient does not respond immediately and dramatically to therapy, then valve replacement should not be delayed, even if the infection is uncontrolled or the patient has had little antibiotic therapy.

Infective endocarditis

Infective endocarditis occurs worldwide, and is defined by infection of a native or prosthetic heart valve, the endocardial surface, or an indwelling cardiac device. The causes and epidemiology of the disease have evolved in recent decades with a doubling of the average patient age and an increased prevalence in patients with indwelling cardiac devices. The microbiology of the disease has also changed, and staphylococci, most often associated with health-care contact and invasive procedures, have overtaken streptococci as the most common cause of the disease. Although novel diagnostic and therapeutic strategies have emerged, 1 year mortality has not improved and remains at 30%, which is worse than for many cancers. Logistical barriers and an absence of randomised trials hinder clinical management, and longstanding controversies such as use of antibiotic prophylaxis remain unresolved. In this Seminar, we discuss clinical practice, controversies, and strategies needed to target this potentially devastating disease.

Timing for pacing after acquired conduction disease in the setting of endocarditis

A 53-year-old gentleman with a history of a mechanical aortic valve presented to the emergency department complaining of a sudden right-sided abdominal pain. He was found to have atrioventricular dissociation on his initial electrocardiogram and his blood cultures grew Streptococcus viridans. The suspicion for endocarditis with periaortic abscess was high so a transthoracic echocardiogram was performed and showed a mass in the left ventricular outflow tract. For better visualization, a transesophageal echocardiogram was recommended and revealed a bileaflet mechanical aortic valve with perivalvular abscess and valvular vegetation as well as severe eccentric paravalvular aortic regurgitation. After sterilization, the patient underwent a successful surgery. Postoperatively, he remained in complete heart block and a permanent pacemaker placement was performed after complete sterilization. He tolerated the procedure well and was discharged home in a stable condition. Perivalvular abscess is one of the most common cardiac complications of infective endocarditis and is associated with an increased risk of mortality. It is imperative to have appropriate treatment guidelines established. However, because of the relative nature of the disease process and the acuity at which intervention needs to be done, a true assessment of the duration of antibiotic therapy prior to surgical intervention, timing of pacemaker placement, and the type of pacemaker is controversial.

Double valve replacement and reconstruction of the intervalvular fibrous body in patients with active infective endocarditis

OBJECTIVES

Destruction of the intervalvular fibrous body, though uncommon, occurs due to paravalvular abscess formation following active infective endocarditis. This warrants a highly complex operation involving radical surgical debridement of the intervalvular fibrous body, followed by double valve (aortic and mitral) replacement with patch reconstruction of the anterior mitral annulus, the left ventricular outflow tract and the left atrial roof. The objective of this study was to review the early and mid-term outcomes in patients undergoing this operation.

METHODS

A total of 25 patients underwent double valve replacement with reconstruction of the intervalvular fibrous body for extensive infective endocarditis between January 1999 and March 2012. The mean age was 64.3 ± 10.5 years. Most of the patients (60%) were in New York Heart Association Class III-IV, 12% and in cardiogenic shock. Associated comorbidities like acute renal insufficiency and cerebrovascular accidents were observed in 40 and 20% of patients, respectively. Twenty patients had previous heart valve surgeries. The logistic EuroSCORE predicted risk of mortality was 55.1 ± 22.9%.

RESULTS

Overall, 30-day mortality was 32%. Postoperative complications like low cardiac output, stroke and acute renal failure developed in 16, 28 and 56%, respectively. Thirty-two percent of patients required re-exploration for bleeding. Nine patients were alive at a mean follow-up of 406 days (0-8 years). The 2- and 5-year survivals were 37.0 ± 11.1 and 24.6 ± 12.5%, respectively.

CONCLUSIONS

Double valve replacement with reconstruction of the intervalvular fibrous body for infective endocarditis is a complex, technically challenging operation associated with high perioperative morbidity and mortality. Nevertheless, being the only option available for such complex disease, it should be performed in these patients who, otherwise, face 100% mortality.

Evaluating treatment options for patients with infective endocarditis: when is it the right time for surgery?

Infective endocarditis remains a life-threatening condition with an unchanging incidence and mortality of nearly 30% at 1 year. Surgery is required in 25–50% of acute infections and 20–40% of patients during convalescence. Operative procedures are often technically challenging and high-risk, often due to coexistent multisystem disease. However, international guidelines provide clear indications for surgical intervention, which are applicable for the majority of patients. These are not, however, supported by particularly robust clinical evidence and decision-making often needs to be tailored to the advancing age of the overall patient cohort, the presence of multisystem disease, comorbidities, prior antibiotic therapy of varying duration and the availability of surgical expertise. Native valve endocarditis will be the initial focus of this article, along with subgroups including prosthetic valve endocarditis. We present the treatment options for patients with infective endocarditis, evaluate the evidence-base that supports current clinical practice and attempt to provide an insight and subsequent recommendations for the timing of surgery.

A case of staphylococcal tricuspid valve endocarditis with para-aortic abscess in a patient with bicuspid aortic valve

Paravalvular abscess is a serious complication of infective endocarditis. The aortic valve and its adjacent ring are more susceptible to abscess formation and paravalvular extension than the mitral valve. A 15-years old patient with bicuspid aortic valve presented with staphylococcal tricuspid valve endocarditis complicated by para-aortic abscess that ruptured into the aortic sinus. We report the clinical, laboratory and echocardiographic features and treatment of this patient and conduct a literature review on this subject.

Surgical management and mid-term outcomes of 108 patients with infective endocarditis

This study evaluates the early and mid-term outcomes, predictors of mortality and morbidity and quality of life of patients operated for infective endocarditis. Data on 108 patients undergoing 113 surgical procedures during October 1998 to January 2010 was prospectively collected. NYHA Class was >III in 49 (43.4%) cases. Thirty-seven (33%) patients had isolated mitral valve procedures, 58 (51%) had aortic valve, two had tricuspid valve and 16 had multivalvular procedures. Active endocarditis was noted in 86 (76%) procedures, native valve endocarditis in 105 (93%) and prosthetic valve endocarditis in eight procedures. Logistic EuroSCORE at presentation was >14 in 18 (17%) patients. Staphylococcus aureus was the most common organism isolated. Follow-up was carried out in 76/85 (88.37%) of surviving patients, and the mean follow-up time was 37.2 months. Functional class and quality of life (using EQ-5D Health Questionnaire) were assessed by telephone interviews. NYHA Class on follow-up was I-II in 62/76 (83%). Multivariate predictor of 30-day mortality was peripheral vascular disease (p = 0.025) whilst multivariate predictors of long-term survival were male sex (p = 0.01), peripheral vascular disease (p = 0.02) and bypass time (p = 0.006). The overall survival was 87% at one year and 80% at five years. Thirty-three percent (25/76) patients reported a score reflecting full health. Optimal antibiotic therapy and timely surgical intervention were associated with improved functional class, quality of life and mid-term survival.

Survival of surgically treated infective endocarditis: a comparison with the general Dutch population

BACKGROUND

Infective endocarditis (IE) remains associated with high in-hospital and long-term mortality. The outcome of patients with IE who are operated on has never been put into perspective by comparing it to the age-matched and gender-matched general population. The aim of the present study was to evaluate the long-term mortality of patients with IE who undergo operation in relation to the age-matched and gender-matched general population.

METHODS

A retrospective observational cohort study of 138 patients with IE who underwent consecutive operations (1998-2007) was conducted. Cumulative survival was analyzed using the Kaplan-Meier method. Comparison of patient survival with the general population was done using the Dutch population life table. The standardized mortality ratio was used to assess the degree of late deaths.

RESULTS

The observed in-hospital mortality risk was 10.9%. The observed long-term survival was 85% (95% confidence interval, 78% to 90%), 74% (95% confidence interval, 65% to 79%), 71% (95% confidence interval, 62% to 78%) after 1, 5, and 10 years, respectively. Age-matched and gender-matched survival in the general population was 99%, 93%, and 80% after a follow-up period of 1, 5, and 10 years, respectively. The standardized mortality ratio was 0.99 (95% confidence interval, 0.67 to 1.31).

CONCLUSIONS

Although mortality of IE patients who have undergone operation remains considerable during the immediate postoperative period, the mortality of hospital survivors is, with increasing follow-up time, comparable with the general population.

Role of surgery in infective endocarditis

One-hundred-and-thirteen patients with endocarditis and valvular insufficiency were studied retrospectively with special regard to indications for operation and the optimum time for cardiac valve surgery. Thirty patients (group I) had acute, 63 (group II) subacute and 20 (group III) prosthetic valve endocarditis. Group I: Eleven patients underwent surgery in the acute stage, 8 while bacteremic; 5 of the latter died perioperatively. Of the 19 patients treated medically, 16 died. Group II: All patients underwent operation in a bacteria-free state. The mortality was 5%. Group III: Eight patients had early (less than 60 days postoperatively) and 12 late endocarditis. Total mortality was 40% (71% early and 25% late mortality). Ten patients underwent reoperation, with a mortality of 20%, compared with 60% in the medically treated group. The results support the indication for early operation in acute endocarditis with progressive cardiac failure and renal failure and prosthetic valve endocarditis, even during bacteremia.

Ten years of infective endocarditis: a clinicopathologic study

The records of 46 patients with infective endocarditis diagnosed either clinically or post-mortem were analyzed. Twenty-six patients were over 60 years of age. S. aureus was the predominant organism, almost exclusively found in patients with acute endocarditis. Thirty-six patients had pre-existing heart disease, the most common being non-rheumatic valvular calcification and congenital defects. Two thirds of the patients, especially those with aortic valve regurgitation, developed new or progressive heart failure. A correct clinical diagnosis was established in only 30 patients. Twenty-three patients died, the mortality being 71% in acute and 32% in subacute disease. Only one of eight patients with prosthetic valve infection died. Four patients required urgent valve replacement. Early surgical intervention should be considered in patients with uncontrolled heart failure.

[Timing and indications for surgical intervention in infective endocarditis]

This paper reviews current knowledge on the indications for and timing of cardiac surgery in patients with infective endocarditis. The main indications for surgery are haemodynamic compromise, persisting infection, peripheral embolisation, large size of vegetations, large valvular and paravalvular damage and infections caused by certain microorganisms.

Endocarditis and associated complications

Echocardiography is a most useful bedside tool to help in the diagnosis and subsequent management of patients with infective endocarditis. Transesophageal echocardiography provides complementary and often incremental information necessary in making a diagnosis, and in identifying associated intracardiac complications. This chapter will focus on the role of echocardiography in the diagnosis and management of infective endocarditis.

In-hospital and long-term mortality in infective endocarditis in injecting drug users compared to non-drug users: a retrospective study of 192 episodes

In a retrospective study, in-hospital and long-term mortality for patients with infective endocarditis (IE) was analysed. The study was conducted at a department of infectious diseases in Stockholm, Sweden. Mortality was compared between injecting drug users (IDUs) and patients without drug abuse (non-IDUs). 192 episodes of IE from 1995 to 2000 were analysed, 60 in IDUs and 135 in non-IDUs, median follow-up 4.4 y. Episodes were classified using the Duke criteria: 145 definite and 47 possible. Of 53 definite episodes in IDUs, 55% were right-sided IE and 43% left-sided IE (including combined left- and right-sided). Surgical treatment was used in 34/145 definite episodes, all being left-sided IE. The in-hospital mortality was 14/145 (9.6%). There was no difference in in-hospital mortality between patient groups with left-sided IE. The IDU patients with left-sided IE had a higher long-term mortality with the increased mortality rate explained by late deaths in the surgically treated IDUs. Treatment results for IDUs with right-sided IE were good with no in-hospital mortality, no relapses and no increase in long-term mortality. This difference in prognosis between left-sided and right-sided IE in IDUs makes high quality echocardiography important to identify patients with left-sided IE and worse prognosis.

Aortic valve endocarditis: is there an optimal surgical timing?

PURPOSE OF REVIEW

Patients with aortic valve infective endocarditis are likely to undergo surgery during the active phase of the disease. The indication and best timing for surgery, however, are still debated. The present review discusses the benefits and risks of early surgery in aortic endocarditis.

RECENT FINDINGS

Patients with acute aortic regurgitation and clinical or echocardiographic signs of poor tolerance require urgent surgery. Other indications for early surgery include severe perivalvular involvement and high embolic risk. Echocardiography plays an important role in the assessment of embolic risk and helps in choosing the best therapeutic strategy. Several recent studies have identified high-risk subgroups of patients that, without surgery, face poor prognosis. Patients with complicated endocarditis, particularly those with congestive heart failure, will benefit most from surgery. Patients with prosthetic valve endocarditis and cerebral complications represent specific subgroups in which surgical decision is more difficult.

SUMMARY

Patients with severe aortic leaflet destruction and congestive heart failure, patients with perivalvular extension or uncontrolled infection, and patients with high embolic risk have poor outcome under medical therapy. Early surgery is necessary in all such patients with 'complicated' endocarditis, unless severe comorbidity is present.

Periannular complications in infective endocarditis involving native aortic valves

The extension of infection in native valve infective endocarditis (IE) from valvular structures to the periannular tissue is incompletely understood. It is unknown, for example, whether the prognosis of patients with aortocavitary fistulae is worse than that of those with nonruptured abscesses. The aims of this study were to determine the distinct clinical characteristics of patients with aortocavitary fistulae and nonruptured abscesses in native valve IE and to evaluate the impact of fistulization on the outcomes of patients with native aortic valve IE complicated with periannular lesions. In a retrospective multicenter study of 2,055 native valve IE episodes, 201 patients (9.8%) with periannular complications in aortic valve IE were identified (46 with aortocavitary fistulization and 155 with nonruptured abscesses). Rates of heart failure (p = 0.07), ventricular septal defect (p <0.001), and third-degree atrioventricular block (p = 0.07) were higher in patients with fistulization. Surgical treatment was undertaken in 172 patients (86%), and in-hospital mortality in the overall population was 29%. Multivariate analysis identified age >60 years (odds ratio [OR] 2.6, 95% confidence interval [CI] 1.3 to 5.2), renal failure (OR 3.0, 95% CI 1.5 to 6.0), and moderate or severe heart failure (OR 2.5, 95% CI 1.2 to 5.2) as independent risk factors for death. There was a trend toward increased in-hospital mortality in patients with aortocavitary fistulae (OR 1.5, 95% CI 0.7 to 3.0). The actuarial 5-year survival rate in surgical survivors was 80% in patients with fistulae and 92% in patients with nonruptured abscesses (log-rank p = 0.6). In conclusion, aortocavitary fistulous tract formation in the setting of native valve IE is associated with higher rates of heart failure, ventricular septal defect, and atrioventricular block than nonruptured abscess. Despite these higher rates of complications, fistulous tract formation in the current era of IE is not an independent risk factor for mortality.

Importance of surgical timing on postoperative outcome in patients with native valve acute endocarditis

BACKGROUND

The present study was undertaken to establish whether surgical outcome could be influenced by surgical timing in patients affected by native valve endocarditis (NVE).

METHODS

From March 2002 to December 2004, 19 patients underwent surgical operation for NVE. Aortic valve replacement (AVR) was performed in ten patients (53%), mitral valve repair (MVRep) was performed in five patients (26%) and multivalvular procedures were performed in the remaining four patients (21%). In three patients (15.5%), emergency surgery was required for refractory congestive heart failure, urgent surgery was necessary in ten patients [in six patients (31%) for paravalvular abscess, in three patients (15.5%) for macrovegetations and in one patient (6%) for systemic embolism, respectively], five patients (26.3%) with isolated valve incompetence underwent elective surgery, whereas delayed surgery was reserved for one patient (6%) because of pre-operative embolic stroke.

RESULTS

There were no surgical procedure, cardiac or infectious related deaths at 30 days in the entire group. One patient died from an intravenous overdose. Follow-up was 100% complete in the 18 hospital survivors and ranged from 4 to 37 months (mean 14.2 +/- 10 months). There were no late death, recurrence of endocarditis, or re-operation at follow-up.

CONCLUSIONS

The surgical results for NVE are excellent if surgical timing criteria are correctly applied during the acute phase of the infectious process. Immediate surgical correction is required when rapid hemodynamic deterioration occurs whereas a more aggressive surgical approach appears to be advisable in the case of paravalvular abscess, macrovegetations or systemic embolism. Delayed surgery is recommended when pre-operative stroke develops.

Complications of native and prosthetic valve infective endocarditis: Update in 2006

Infective endocarditis is a rare disease associated with significant morbidity and mortality. In the past decades, there have been significant improvements in the management of infective endocarditis. Complications are frequent and include heart failure, embolic episodes, periannular complications, and central nervous system events. Surgical therapy has been fundamental in the reduction of mortality in complicated cases. This paper is an overview of the main complications of native and prosthetic infective endocarditis and its treatment.

Predictors of Mortality in Paravalvular Abscess

BACKGROUND

Paravalvular abscess formation is an ominous complication of infective endocarditis; however, prognostic variables in paravalvular abscess are poorly defined.

METHODS

We examined our experience in patients with paravalvular abscess between 1987 and 2004. Clinical, echocardiographic, microbiologic, and surgical data were examined.

RESULTS

There were 45 patients (17 females), age 57 +/- 17 years. Twenty-four patients had prosthetic valve endocarditis. Methicillin-sensitive Staphylococcus aureus and coagulase-negative S. aureus were the most common organisms accounting for 25 (56%) cases. Thirty-eight patients (84%) underwent surgery during initial admission. Surgical mortality was 7%, in-hospital mortality was 31%, and 1-year mortality was 38%. Between patients who died and patients who survived, there were no differences in age (61 +/- 20 years vs 55 +/- 15 years, P = .3), type of microorganism, presence of prosthetic heart valves (47% vs 57%), presence of moderate to severe or severe regurgitation of involved valve (47% vs 57%, P = .37), presence of associated valvular vegetation (93% vs 93%), area of abscess (5.6 +/- 2.9 cm2 vs 4.4 +/- 3.2 cm2, P = .39), left ventricular systolic function (56% +/- 13% vs 56% +/- 10%, P = .9), white cell count (13 +/- 4 vs 13 +/- 7, P = .9), or polymorphonuclear leukocytosis (86% +/- 6% vs 81% +/- 9%, P = .1). Patients who died were sicker on admission compared with those who survived (33% had stroke or altered mental status vs 7%, P = .03) and had worse renal function compared with those who survived (creatinine 4 +/- 4 mg/dL vs 1.6 +/- 1.9 mg/dL, P = .009).

CONCLUSION

Neurologic impairment and renal impairment are significant determinants of 1-year survival in patients who present with paravalvular abscess.

Clinical characteristics and outcome of aortic endocarditis with periannular abscess in the International Collaboration on Endocarditis Merged Database

The aims of this study were to determine the clinical characteristics and outcome of patients who had definite infective endocarditis (IE) complicated by aortic ring abscess formation that was detected with transesophageal echocardiography (TEE) and to determine the prognostic significance of abscess formation in aortic valve IE. Patients who had aortic valve IE were selected from the International Collaboration on Endocarditis Merged Database (ICE-MD) if they underwent TEE. Among 311 patients who had definite aortic valve IE, 67 (22%) had periannular abscesses. They were more likely to have infection in the setting of a prosthetic valve (40% vs 19%, p <0.001) and coagulase-negative staphylococcal IE (18% vs 6%, p < 0.01) and less likely to have streptococcal IE than were patients who did not develop abscess (28% vs 46%, p = 0.01). Systemic embolization, central nervous system events, and heart failure did not differ between those who developed abscess and those who did not, but power was limited. Patients who had abscess were more likely to undergo surgery (84% vs 36%, p <0.001), and their in-hospital mortality rate was higher (19% vs 11%, p = 0.09). Multivariate analysis of prognostic factors of mortality in aortic IE identified age (odds ratio [OR] 1.6, 95% confidence interval [CI]1.2 to 2.1), Staphylococcus aureus (S. aureus) infection (OR 2.4, 95% CI 1.1 to 5.2), and heart failure (OR 2.9, 95% CI 1.4 to 6.1) as variables that were independently associated with increased risk of death. Periannular abscess formation showed a nonsignificant trend toward an increased risk of death (OR 1.9, 95% CI 0.9 to 3.8). Multivariate analysis of prognostic factors of mortality in complicated aortic IE with abscess formation identified S. aureus infection (OR 6.9, 95% CI 1.6 to 29.4) as independently associated with increased risk of death. In conclusion, in the current era of TEE and high use of surgical treatment, periannular abscess formation in aortic valve IE is not an independent risk factor for mortality. S. aureus infection is an independent prognostic factor for mortality in patients who have abscess formation.

Bacteriological Outcome after Valve Surgery for Active Infective Endocarditis: Implications for Duration of Treatment after Surgery

BACKGROUND

There has been no systematic evaluation of outcome after surgery for infective endocarditis with respect to duration of antibiotic treatment.

METHODS

We performed a retrospective chart review of episodes of valve surgery for active infective endocarditis at Green Lane Hospital (Auckland, New Zealand) for 1963-1999. We recorded the duration of antibiotic treatment before and after valve surgery; the extent of infection at operation; Gram stain, culture, and histopathological testing results for valve samples; and the bacteriological outcome after surgery. The primary outcome measure was relapse, defined as endocarditis due to the same species within 1 year after surgery.

RESULTS

For the 358 patients in our study, the median duration of follow-up was 4.8 years. Thirty-two patients (9%) had 36 subsequent episodes of endocarditis. Relapse occurred after 3 (0.8%) of the operations (95% CI, 0.2%-2.0%). Relapse of infection was unrelated to the duration of antibiotic treatment before or after surgery, positive valve culture results, positive Gram stain results, or perivalvular infection. Since 1994, we have reduced the duration of antibiotic treatment by approximately 7 days for those with positive valve culture results and by approximately 14 days for those with negative valve culture results, without any increase in the number of relapses.

CONCLUSIONS

Relapse is an uncommon event following surgery for endocarditis. Commonly suggested indications for prolonging postoperative treatment are not associated with higher relapse rates, and their relevance is debatable. We conclude that it is unnecessary to continue treatment for patients with negative valve culture results for an arbitrary 4-6-week period after surgery. Two weeks of treatment appears to be sufficient, and, for those operated on near the end of the standard period of treatment, simply completing the planned course should suffice.

Enterococcal endocarditis: 107 cases from the international collaboration on endocarditis merged database

PURPOSE

To describe clinical features and outcomes of enterococcal left-sided native valve endocarditis and to compare it to endocarditis caused by other pathogens.

SUBJECTS AND METHODS

Patients in the International Collaboration on Endocarditis-Merged Database were included if they had left-sided native valve endocarditis. Demographic characteristics, clinical features, and outcomes were analyzed. Multivariable analysis evaluated enterococcus as a predictor of mortality.

RESULTS

Of 1285 patients with left-sided native valve endocarditis, 107 had enterococcal endocarditis. Enterococcal endocarditis was most frequently seen in elderly men, frequently involved the aortic valve, tended to produce heart failure rather than embolic events, and had relatively low short-term mortality. Compared to patients with non-enterococcal endocarditis, patients with enterococcal endocarditis had similar rates of nosocomial acquisition, heart failure, embolization, surgery, and mortality. Compared to patients with streptococcal endocarditis, patients with enterococcal endocarditis were more likely to be nosocomially acquired (9 of 59 [15%] vs 2 of 400 [1%]; P <.0001) and have heart failure (49 of 107 [46%] vs 234 of 666 [35%]; P = 0.03). Compared to patients with S. aureus endocarditis, patients with enterococcal endocarditis were less likely to embolize (28 of 107 [26%] vs 155 of 314 [49%]; P <.0001) and less likely to die (12 of 107 [11%] vs 83 of 313 [27%]; P = 0.001). Multivariable analysis of all patients with left-sided native valve endocarditis showed that enterococcal endocarditis was associated with lower mortality (odds ratio [OR] 0.49; 95% confidence interval [CI] 0.24 to 0.97).

CONCLUSIONS

Enterococcal native valve endocarditis has a distinctive clinical picture with a good prognosis.

Mitral valve repair for active culture positive infective endocarditis

OBJECTIVE

To describe the clinical and echocardiographic outcome after mitral valve (MV) repair for active culture positive infective MV endocarditis.

PATIENTS AND METHODS

Between 1996 and 2004, 36 patients (mean (SD) age 53 (18) years) with positive blood culture up to three weeks before surgery (or positive culture of material removed at operation) and intraoperative evidence of endocarditis underwent MV repair. Staphylococci and streptococci were the most common pathogens. All patients had moderate or severe mitral regurgitation (MR). Mean New York Heart Association (NYHA) class was 2.3 (1.0). Follow up was complete (mean 38 (19) months).

RESULTS

Operative mortality was 2.8% (one patient). At follow up, endocarditis has not recurred. One patient developed severe recurrent MR and underwent valve replacement and one patient had moderate MR. There were two late deaths, both non-cardiac. Kaplan-Meier five year freedom from recurrent moderate to severe MR, freedom from repeat operation, and survival were 94 (4)%, 97 (3)%, and 93 (5)%, respectively. At the most recent review the mean NYHA class was 1.17 (0.3) (p < 0.0001). At the latest echocardiographic evaluation, left atrial diameters, left ventricular end diastolic diameter, and MV diameter were significantly reduced (p < 0.05) compared with preoperative values.

CONCLUSIONS

MV repair for active culture positive endocarditis is associated with low operative mortality and provides satisfactory freedom from recurrent infection, freedom from repeat operation, and survival. Hence, every effort should be made to repair infected MVs and valves should be replaced only when repair is not possible.

[Infective endocarditis of a rare etiology (Serratia marcescens)]

Infective endocarditis (IE) is a unique diagnostic and therapeutic challenge. It is a severe disease, fatal before penicillin discovery. Atypical presentations frequently led to delayed diagnosis and poor outcome. There was little information about the natural history of the vegetations during medical treatment or the relation of morphologic changes in vegetation to late complications. Application of a new diagnostic criteria and echocardiography, increased the number of definite diagnosis. Trans-thoracic and trans-esophageal echocardiography had an established role in the management of patients with IE. The evolution of vegetation size, its mobility, and consistency, the extent of the disease, and the severity of valvular regurgutation were related to late complications. With therapeutic options including modern antibiotic treatment and early surgical intervention IE turned out to be a curable disease. Reduction in mortality also depended on prevention. Antibiotic prophylaxis of IE was important, but low mortality was also the result of early treatment, especially in the event of early recognition of symptoms and signs of the disease.

Aorto-cavitary fistulous tract formation in infective endocarditis: clinical and echocardiographic features of 76 cases and risk factors for mortality

AIMS

To investigate the clinical features, echocardiographic characteristics, management, and prognostic factors of mortality of aorto-cavitary fistulization (ACF) in infective endocarditis (IE). Extension of infection in aortic valve IE beyond valvular structures may result in peri-annular complications with resulting necrosis and rupture, and subsequent development of ACF. Aorto-cavitary communications create intra-cardiac shunts, which may result in further clinical deterioration and haemodynamic instability.

METHODS AND RESULTS

In a retrospective multi-centre study over 4681 episodes of IE, a total of 76 patients with ACF [1.6%, confidence interval (CI) 95%: 1.2-2.0%] diagnosed by echocardiography or during surgery were identified. Fistulae were found in 1.8% of cases of native valve IE and in 3.5% of cases of prosthetic valve IE from the general population and in 0.4% of drug abusers. PVE was present in 31 (41%) cases of ACF. Transthoracic and transoesophageal echocardiography detected the fistulous tracts in 53 and 97% of cases, respectively. Peri-annular abscesses were detected in 78% of cases, fistulae originated in similar rates from the three sinuses of Valsalva, and the four cardiac chambers were equally involved in the fistulous tracts. Heart failure (HF) developed in 62% of cases and surgery was performed in 66 (87% CI 95% 77-93%) patients with a mortality of 41% (95% CI 30-53%) in the overall population. Multivariate analysis identified HF (OR 3.4, CI 95% 1.0-11.5), prosthetic IE (OR 4.6, CI 95% 1.4-15.4) and urgent or emergency surgical treatment (OR 4.3, CI 95% 1.3-16.6) as variables significantly associated with an increased risk of death. Major complications during follow-up (death, re-operation, or re-admission for HF) among the five operative survivors with residual fistulae occurred in 20 and 100% of patients at 1 and 2 years, respectively.

CONCLUSION

Aorto-cavitary fistulous tract formation is an uncommon but extremely serious complication of IE. In-hospital mortality was exceptionally high despite aggressive management with surgical intervention in the majority of patients. Prosthetic IE, urgent surgery, and the development of HF identify the subgroup of patients with IE and ACF that have significantly increased risk of in-hospital death.

Comparison of outcomes in patients with active infective endocarditis with versus without paravalvular abscess and with and without valve replacement

In 82 patients with infective endocarditis, including 11 with a perivalvular abscess detected by transesophageal echocardiography, age was a significant predictor of in-hospital mortality (p <0.001). At 3.8-year follow-up, 5 of 7 patients with an abscess who had valve replacement and 2 of 4 patients with an abscess who did not have surgery survived (p = NS); 13 of 22 patients (59%) with no abscess who had valve replacement and 20 of 49 patients (41%) with no abscess who did not have surgery survived (p = NS).

Risk factors for systemic emboli in infective endocarditis

A retrospective study was undertaken to analyse the risk factors for systemic emboli in infective endocarditis. Patients (n = 80; 70% males; mean age 65 years; range 20-91 years) with infective endocarditis, as defined by the Duke criteria and diagnosed using transoesophageal echocardiography during the period January 1995 to March 2001, were included. The average time between the start of the illness and the beginning of antibiotic treatment was 55 days (range 0-405 days). The pathogens identified were streptococci (n = 47), staphylococci (n = 11), enterococci (n = 9), and others (n = 4). In nine cases, blood cultures were sterile. Thirty patients with at least one embolic episode were compared with 50 control patients. According to univariate analysis, the main risk factor for systemic emboli was the size of the vegetation (12.4 mm vs. 7.8 mm; p = 0.0005). The risk of emboli was 57% when the vegetation measured > 10 mm and only 22% when it was < 10 mm (p = 0.003). The mobility of the vegetation was also a risk factor: 48% if the vegetation was mobile; and 9% if fixed (p = 0.003). Sex, age, pathogen, antibiotic treatment, type of valve and the number and position of the vegetations were not found to be risk factors. With multivariate analysis, only mobility was identified as a risk factor. Overall, mobile vegetations > 10 mm in size were associated with an increased risk of embolic episodes in infective endocarditis.

Current best practices and guidelines. Indications for surgical intervention in infective endocarditis

Optimal diagnosis and management of patients with infective endocarditis requires sound clinical judgment based on extensive experience. This is especially important in regard to the indications and timing for surgery. To achieve the best possible outcomes, surgical intervention during treatment is required in 25% to 30% of patients with infective endocarditis. Heart failure and progressive left-sided valvular dysfunction are the most common indications for operation. Valve repair should be considered as an alternative to valve replacement whenever feasible, especially in younger patients. Successful management of perivalvular abscesses and prosthetic valve infections requires radical removal of infected tissue followed by reconstructive procedures performed by experienced surgeons. Emergency or urgent surgery should seldom be delayed.

Gram stain, culture, and histopathological examination findings for heart valves removed because of infective endocarditis

Retrospective chart review was undertaken for 480 patients who underwent a total of 506 valve replacements or repair procedures for infective endocarditis. The influence of preoperative antimicrobial treatment on culture, Gram stain, and histopathological examination findings for resected valve specimens was examined. When valves were removed before the end of treatment, organisms were seen on the Gram stain of ground valve material performed in the microbiology laboratory and on Gram-stained histopathological sections in 231 (81%) of 285 and 140 (67%) of 208 specimens, respectively (P=.0007). Gram-positive cocci were either cultured from or observed in excised valve tissue in 42 (67%) of 63 episodes involving negative preoperative blood cultures. Positive Gram stain results for microbiological specimens should be reintroduced into the definite pathological criteria for infective endocarditis. When deciding on how long to continue antimicrobial therapy after valve replacement for endocarditis, valve culture results should be the only laboratory finding taken into account, because it takes months for dead bacteria to be removed from sterile vegetations.

Diagnosis and management of bacterial endocarditis in 2003

The diagnosis of infective endocarditis has been notoriously difficult. Over the last decade, the modified Duke criteria have assumed an increasingly important role in the early detection of this often occult disease. Echocardiography has assumed increasing importance. Transesophageal echocardiography is recognized as more sensitive and specific than transthoracic echocardiography at detecting vegetations less than 10 mm in diameter. Vegetations greater than 10 mm in diameter are thought to be at increased risk of embolizing. Combined medical and surgical medical management result in the lowest mortality for those patients with hemodynamic compromise.

Stentless aortic valves as an alternative to homografts for valve replacement in active infective endocarditis complicated by ring abscess

BACKGROUND

The valve substitute of choice in active infective aortic valve endocarditis complicated by annulus abscess in our institution is the cryopreserved homograft. To avoid implantation of any prosthetic material, the Shelhigh No-React stentless valves and conduits may be considered an alternative when no suitable homograft is available.

METHODS

Between March 1986 and January 2001, 452 homografts were implanted in the aortic position. From January 2000 to August 2001, 75 Shelhigh No-React prostheses were implanted at our institution. In 25 consecutive patients (study group) with aortic annulus abscess, urgent aortic valve replacement with the Shelhigh SuperStentless and Stentless Aortic Valve Conduit was undertaken. Patients (16 male, 9 female; age, 49 +/- 19 years) were studied with follow-up until March 2002. The control group comprised 68 consecutive historical patients (46 male, 22 female; age, 53 +/- 14.4 years) with similar disease treated between January 1997 and December 1999 in whom an aortic homograft was implanted. This group was also followed up until March 2002. Demographic data and preoperative characteristics of the patients were without significant differences. Patients were studied by echocardiography.

RESULTS

Sixty-day mortality was 16% (11 patients) in the control group compared with 12% (3 patients) in the study group. Recurrent infection occurred in 4% in both groups. The instantaneous and mean Doppler gradients yielded no significant differences (19.4 +/- 10.4 mm Hg and 11.8 +/- 5.7 mm Hg versus 18.2 +/- 8.7 mm Hg and 10.9 +/- 5.3 mm Hg, respectively). The mean effective orifice area calculated from Doppler flow velocity for the stentless valve was 2.3 +/- 0.6 cm2. Preoperative evaluation of left ventricular dimensions and global left ventricular systolic function did not vary significantly between the two groups. However, postoperatively evaluated left ventricular end-diastolic diameter dimensions in the study group were significantly smaller than those in the control group (47.6 +/- 7.9 mm versus 56 +/- 9.5 mm; p = 0.05). Ejection fraction was similar in both groups (56.2% +/- 12.8% for the study [Shelhigh] and 52.6% +/- 16.8% for the control [homograft] group).

CONCLUSIONS

Our experience with both the Shelhigh No-React SuperStentless and Stentless Aortic Valve Conduit in patients with native or prosthetic aortic valve endocarditis appears to demonstrate good results, similar to those of cryopreserved homografts. Ease of implantation and favorable effective orifice area and pressure gradients, as well as the No-React anticalcification treatment, are promising factors.

Infective endocarditis: determinants of long term outcome

OBJECTIVE

To evaluate predictors of long term prognosis in infective endocarditis.

DESIGN

Retrospective cohort study.

SETTING

Tertiary care centre.

PATIENTS

212 consecutive patients with infective endocarditis between 1980 and 1995

MAIN OUTCOME MEASURES

Overall and cardiac mortality; event-free survival; and the following events: recurrence, need for late valve surgery, bleeding and embolic complications, cerebral dysfunction, congestive heart failure.

RESULTS

During a mean follow up period of 89 months (range 1-244 months), 56% of patients died. In 180 hospital survivors, overall and cardiac mortality amounted to 45% and 24%, respectively. By multivariate analysis, early surgical treatment, infection by streptococci, age < 55 years, absence of congestive heart failure, and > 6 symptoms or signs of endocarditis during active infection were predictive of improved overall long term survival. Independent determinants of event-free survival were infection by streptococci and age < 55 years. Event-free survival was 17% at the end of follow up both in medically-surgically treated patients and in medically treated patients.

CONCLUSIONS

Long term survival following infective endocarditis is 50% after 10 years and is predicted by early surgical treatment, age < 55 years, lack of congestive heart failure, and the initial presence of more symptoms of endocarditis.

Current best practices and guidelines indications for surgical intervention in infective endocarditis

Optimal diagnosis and management of patients with infective endocarditis requires sound clinical judgment based on extensive experience. This is especially important in regard to the indications and timing for surgery. To achieve the best possible outcomes, surgical intervention during treatment is required in 25% to 30% of patients with infective endocarditis. Heart failure and progressive left-sided valvular dysfunction are the most common indications for operation. Valve repair should be considered as an alternative to valve replacement whenever feasible, especially in younger patients. Successful management of perivalvular abscesses and prosthetic valve infections requires radical removal of infected tissue followed by reconstructive procedures performed by experienced surgeons. Emergency or urgent surgery should seldom be delayed.

Periannular extension of infective endocarditis

OBJECTIVES

This prospective study was designed to assess the current clinical course, risk factors, microbiologic profile and echocardiographic findings of patients with left-sided endocarditis and perivalvular complications.

BACKGROUND

Periannular complications worsen the prognosis of patients with endocarditis. The relation between these complications and the clinical and microbiologic data has not been clearly defined.

METHODS

In this clinical cohort study, 211 patients with left-sided endocarditis, according to the Duke criteria, were prospectively recruited. All patients underwent conventional and transesophageal echocardiography. The mean follow-up interval was 151 days.

RESULTS

Perivalvular complications were detected in 78 patients (37%). The incidence of periannular extension of infection in native and prosthetic valves was 29% and 55%, respectively. The presence of prosthesis (relative risk [RR] 1.88, 95% confidence interval [CI] 1.35 to 2.64) and previous endocarditis (RR 1.78, 95% CI 1.16 to 2.7) were the only pre-existing heart conditions associated with perivalvular complications. Aortic infection (RR 1.8, 95% CI 1.23 to 2.66) and the development of atrioventricular (AV) block (RR 2.55, 95% CI 1.91 to 3.41) were related with the existence of these complications. Coagulase-negative staphylococci were very common in patients with perivalvular complications (RR 1.77, 95% CI 1.21 to 2.59), and small vegetations were more frequent in these patients (RR l.45, 95% CI 0.95 to 2.22). An operation was more frequently performed in patients with perivalvular complications, but mortality was similar in patients with and without these complications.

CONCLUSIONS

Aortic infection, prosthetic endocarditis, new AV block and coagulase-negative staphylococci were independent risk factors of periannular complications. The period between symptom onset and diagnosis, the incidence of pericardial effusion and persistent signs of infection were similar between patients with and without perivalvular complications. Patients with perivalvular complications did not demonstrate a difference in the presence or size of vegetations or the frequency of embolism. An operation was more frequently performed in these patients, but mortality was similar in both groups.