Role of surgery in infective endocarditis

Early surgery for active infective endocarditis

OBJECTIVE

The timing of surgery for active infective endocarditis remains controversial. In this report, we have reviewed 26 patients who underwent surgery for active infective native-valve endocarditis between April 1992 and December 1998.

PATIENTS AND METHOD

There were 19 male and 7 female patients (mean age 45 years). The aortic valve was involved in 8 patients, the mitral valve in 6 patients, tricuspid valve in 2 patients, both aortic and mitral valves in 7 patients, both aortic and tricuspid valve in 2 patients, and both mitral and tricuspid valve in one patient. The most common microorganisms were streptococcal species. Preoperative high New York Heart Association functional class (III and IV) was presented in 20 patients (77%). Progressive heart failure and the echocardiographic findings of vegetation (larger than 1 cm) were the main operative indications. Emergency or urgent surgery was required in 18 patients (70%). All patients underwent valve replacement, involving 25 mechanical prosthesis and 8 bioprosthesis.

RESULTS

The operative mortality was 7.8% (n = 2). In the two patients who died, the infection had extended to the deep cardiac tissue and to the cerebral artery. The mean follow-up of the 24 survivors was 33 months (range from 6 to 82 months). There was no late death and no recurrence of infective endocarditis.

CONCLUSION

In case of active infective endocarditis, early surgical intervention is recommended in patients with rapidly progressive cardiac deterioration or vegetation seen on echocardiography.

Are blood and valve cultures predictive for long-term outcome following surgery for infective endocarditis?

OBJECTIVE

To evaluate whether perioperative bacteria identification in blood and/or in valve cultures can predict early and late outcome of surgery for infective endocarditis, a retrospective study was performed.

METHODS

Between January 1978 and December 1998, 232 patients, 79 (34.1%) female and 153 (65.9%) male with mean age of 44. 95+/-1.03 years (range 8-79) underwent surgery for infective endocarditis on a native (162 cases) or prosthetic (70 cases) valve. Patients were divided into three groups according to the perioperative x of microbiological tests: Group A: patients with preoperative positive blood cultures (83 cases); Group B: patients with positive valve cultures (35 cases); Group C: patients with negative blood and valve cultures (114 cases). Categorical values were compared by chi(2) analysis, whereas continuous data were compared by ANOVA and Bonferroni correction for post hoc comparisons. Analysis of late survival and complications was performed with Kaplan-Meier and Log Rank test. Late mortality, reoperation, perivalvular leak, recurrence of infection were considered as treatment failure. All data were presented as mean+/-standard error.

RESULTS

Hospital mortality was 10.8% (9/83) in Group A, 8.6% (3/35) in Group B, and 14.9% (17/114) in Group C (P=0.52; not significant (NS)). Ten-year survival was 62.7+/-8% in Group A, 43.9+/-19% in Group B and 62.7+/-7% in Group C (P=0.38; NS). Ten-year freedom from reoperation was 85.2+/-6% in Group A, 37.9+/-20% in Group B and 80+/-6% in Group C (P=0.0034). Ten-year freedom from treatment failure was 56.3+/-8% in Group A, 31.6+/-16% in Group B and 55. 3+/-7% in Group C (P=0.46; NS).

CONCLUSIONS

Positive blood and tissue cultures are not predictive for hospital mortality and late treatment failure in patients with infective endocarditis. Positive valve cultures, a common finding in patients with staphylococcal endocarditis, are predictive for a higher risk of reoperation.

A 10-year retrospective study of infective endocarditis at a university hospital with special regard to the timing of surgical evaluation in S. viridans endocarditis

A total of 154 episodes of infective endocarditis (IE) in 149 patients were studied retrospectively with special regard to the major aetiological groups and the surgical evaluation. There were 136 episodes of native valve endocarditis (NVE) (88%) and 18 episodes of prosthetic valve endocarditis (PVE) (12%). Three major groups of NVE crystallized: Streptococcus viridans in 37 (27%), Staphylococcus aureus in 39 (29%) and culture negative IE in 28 (21%) episodes. In these groups surgery during the active phase was required in 41, 28 and 18%, respectively. At the operation myocardial abscess was found in as many as 7/15 cases with S. viridans, but in only in 3/11 cases with S. aureus and 1/5 cases with culture negative IE. The mean duration of preoperative antibiotic treatment was 34 d. This long period of unsuccessful pharmacotherapy, preceded by a mean of 47 d from start of symptoms to admission to hospital, has probably resulted in the high frequency of myocardial abscess in S. viridans NVE. Surgical evaluation should be considered when fever persists beyond 10 d of adequate treatment, even in the absence of clinically apparent complications. Among the PVE episodes, 11/18 were managed with pharmacological treatment alone. Uncomplicated PVE may thus often be successfully treated with antibiotics alone.

Surgical treatment of endocarditis

Since early investigators first suggested that the treatment of endocarditis should include valve replacement for infections not readily controlled with medical therapy alone, the role of surgery has become expanded, yet refined, to improve the outcome of patients with this potentially fatal disease. Innovative surgical techniques have also been developed in an effort to improve the results of surgical treatment for complex sequelae of invasive infections. This article examines the current indications for surgical intervention, compares the various surgical options, and assesses the expected short-and long-term outcome after valve replacement for patients with native valve or prosthetic valve endocarditis.

Prosthetic valve endocarditis

Prosthetic valve endocarditis is an infrequent but serious complication of valve surgery. It occurred in 25 (3.2%) of 772 patients who received aortic, mitral or double valve replacement in 1971-1987. The total follow-up time was 3,976 patient years, giving an incidence of 0.63/100 patient years. Staphylococci were the most common of the cultured organisms in early and late infections-60% and 64%, respectively. The endocarditis was disclosed at autopsy in two cases. Treatment was antibiotics alone in 11 cases, and surgery was required in 12, the indication always being congestive heart failure. C-reactive protein level fell more rapidly than erythrocyte sedimentation rate in response to antibiotic or surgical management. The mortality rate was 73% in the antibiotic group and 33% in the surgical group. The findings demonstrated that an infected valve prosthesis should be replaced without delay if complications develop.

Valvular heart disease: clinical approach to acute decompensation of left-sided lesions

Acute valvular heart disease is often life-threatening. The diagnosis of acute valvular decompensation is made by attention to the physical assessment and appropriate use of diagnostic techniques. Recent advances in valvular heart disease have centered around noninvasive diagnostics. Doppler echocardiography can accurately diagnose and quantify stenotic and regurgitant lesions; its use with M-mode and two-dimensional echocardiography makes these the noninvasive diagnostic procedures of choice. Acute decompensation is often related to preexisting critical aortic or mitral stenosis, or more commonly, acute severe regurgitation. Although of different etiologies, acute mitral and aortic regurgitation are associated with similar diagnostic and therapeutic modalities. Emergency treatment consists of vasodilator and, possibly, inotropic therapy. However, definitive therapy generally requires surgical intervention.