Emergency replacement of valves in endocarditis

Indications for cardiac surgery in patients with active infective endocarditis

Currently, absolute indications for valve replacement during active infective endocarditis include severe heart failure, the presence of an infecting microorganism that is not susceptible to available antimicrobial agents, and, in patients with an infected prosthetic valve, an unstable device. Relative indications include an etiologic microorganism other than a susceptible Streptococcus, relapse after presumed effective therapy, evidence of intracardiac extension of the infection, two or more systemic emboli, vegetations large enough to be demonstrated by echocardiography, and, in patients with an infected prosthetic device, early disease and periprosthetic leak. With use of data from the medical literature, a study generated by the cardiovascular surgical group at the University of Alabama School of Medicine, and a brief cost analysis, a point system was constructed to assist in decision-making concerning surgery in patients with active infective endocarditis. The usefulness of this system will depend on experience generated from its utilization in a larger number of patients as well as new data relative to a more complete understanding of the risks and benefits of surgery in this condition.

Infective endocarditis: a lethal disease

One-hundred-and-eighty-nine episodes of infective Endocarditis were seen in 177 patients in the Green Lane Cardiology Unit over a 18-year period. Hospital survival was 79% and 13-year actuarial survival was 47%. A number of factors including the underlying cardiac lesion, infecting organism, clinical features and surgical intervention were related to outcome. No patient with extreme heart failure survived without operation. Hospital survival in patients with severe heart failure was 69% (9/13 patients) where surgery was carried out before completion of antibiotic treatment, and 40% (6/15 patients) where the antibiotic course was completed. Survival was 53% in patients who still had a fever after one week of antibiotic treatment and 96% if the temperature was normal. In 61% of patients with a fever at one week, extended infected pannus was present compared with 6--10% where the temperature was normal. In patients undergoing operation before completion of antibiotics, the surgical mortality was higher but neither the incidence of recurrence of endocarditis nor the need for re-operation was increased. We believe that better results will be achieved with a policy of surgical intervention when signs of infection and heart failure have not settled within one week of treatment.

Surgical management of left ventricular-aortic discontinuity complicating bacterial endocarditis

Successful hemodynamic repair of left ventricular-aortic discontinuity complicating bacterial endocarditis in 2 patients was achieved using a composite valve-woven Dacron tube graft. The prosthetic valve was sutured without tension into the remaining aortic annulus, ventricular muscle, and base of the aortic leaflet of the mitral valve. Use of the composite graft allows adequate debridement of the abscess, restores ventricular-aortic continuity, excludes the abscess wall from systemic pressure, and does not require saphenous vein coronary bypass. Total exclusion of the aortic root, as described, is a lifesaving alternative repair in the care of desperately ill patients with this condition.

Valve replacement in patients with active infective endocarditis

Eleven of 138 patients with infective endocarditis (IE) who underwent cardiac valve replacement for IE during a 12 1/2-year period had active IE. Eight of the 11 (all with aortic IE) had positive blood cultures within 48 hours preoperatively; six of the eight had positive Gram stains and cultures of the excised cardiac tissue. All 11 patients had Class IV cardiac functional disability (New York Heart Association classification) at the time of surgery. Staphylococci (three patients with Staphylococcus aureus and one with S. epidermidis) were the most frequent isolates. Three patients died; two of these three deaths occurred in patients who had a sudden onset preoperatively of severe aortic regurgitation and heart failure. In one patient (S. epidermidis infection) prosthetic valve endocarditis developed. Cardiac valve replacement may be performed successfully in patients with active IE even when blood cultures are positive in the immediate perioperative period. The hemodynamic status of patients with IE should be the determining factor in the timing of cardiac valve replacement, rather than the activity of the infection or the length of preoperative antimicrobial therapy. A radical surgical procedure may be necessary in patients with myocardial or aortic abscesses in whom conventional aortic valve replacement is not possible.

Surgical treatment of acute aortic regurgitation in infective endocarditis

During a six-year period 15 consecutive patients with isolated aortic regurgitation due to infective endocarditis were encountered. None had prior significant aortic valve disease. Elective valve replacement was performed in 13 patients; emergency operation was needed in only 1 patient because of intractable pulmonary edema. One patient died suddenly from acute heart block while undergoing medical treatment. Preoperative cardiac catheterization studies in 10 of the 14 patients revealed gross elevations of left ventricular end-diastolic pressure, pulmonary hypertension, depressed cardiac output, and 3 to 4+ aortic regurgitation. There was 1 early and 1 late postoperative death, both due to systemic embolism, yielding an overall surgical mortality of 14%. After a mean follow-up of 18 months, 10 of the 11 patients are in New York Heart Association Functional Class I. Most patients with acute aortic regurgitation secondary to infective endocarditis have clinically observable congestive heart failure and will eventually require valve replacement. If congestive heart failure can be stabilized by a medical regimen, a course of antibiotic therapy can be administered and elective valve replacement can be performed. The time taken for preoperative antibiotic treatment is not associated with irreversible myocardial damage sufficient to influence the results of operation.

Echocardiography in bacterial endocarditis

We examined 129 standard M-mode echocardiograms obtained in 65 patients (16 to 73 years old) with bacterial endocarditis. Twenty of the 22 patients with vegetations recognizable by echocargiography died, or underwent cardiac operation (mean interval from admission 22 days, and range two to 120 days). Vegetations were seen on the echocardiograms in 22 (aortic 10, mitral nine and tricuspid three, with anatomic confirmation in 19). Of patients without vegetations on echocardiography none underwent emergency operation or died as a result of cardiac disease (mean follow-up period of 14 months, range of two to 38 months). Other echocardiographic findings in those with vegetations included early mitral-valve closure (six), "flail" aortic leaflet (three), and "flail" mitral leaflet (three). Echocardiography can provide a rapid, reliable noninvasive diagnosis of bacterial vegetations in certain patients with bacterial endocarditis and may identify patients with more severe disease who may require operative intervention.

A comparative study of 48 host valve and 24 prosthetic valve endocarditis cases

Forty-eight cases of host valve endocarditis and 24 cases of prosthetic valve endocarditis occurring during a concurrent period of time were analyzed to assess differences between the two groups. The over-all incidence of prosthetic valve endocarditis during this 40 month period was 4.4%. The symptoms and signs in both groups were similar, except that PVE patients had more frequent occurrences of changing heart murmurs and splenic and cerebral emboli. Spleen scans may be helpful in the diagnosis of selected cases of culture-negative prosthetic valve endocarditis. There was no significant difference between the two groups for the various infecting microorganisms. However, the culture-negative prosthetic valve group had a mortality rate of 77.7% compared to 46.2% for the host valve group. In the HVE patients the oral cavity or urinary tract was the probable source of infection in 50.0% of the patients. In about one third of HVE cases, there was strong evidence that the infection was related to a therapeutic procedure, whereas nearly half of the PVE patients had clinical evidence of an extracardiac infection at the time of open-heart surgery. We emphasize the need for good pre- and postoperative surveillance to eliminate possible predisposing infections and appropriate antibiotic prophylaxis in all patients with valvular disease at times of risk. The survival rate in patients with prosthetic valve endocarditis was highest in those patients who received "appropriate" antibiotics and, if significant congestive heart failure was present, surgical intervention was necessary.

Bacterial endocarditis at Blegdamshospitalet in Copenhagen 1944-1973

The clinical pattern of 34 cases ob subacute bacterial endocarditis (SBE) and 46 cases of acute bacterial endocarditis (ABE) is outlined. In the SBE group the mortality was 9% and the incidence of major complications during the treatment period was 15% for cerebrovascular accidents, 9% for other systemic or pulmonary emboli and 9% for congestive heart failure indicating valvular damage. In 31 bacteriologically proven cases growth was obtained in 68% of all blood cultures, and in 94% of the cases at least one positive culture was among the first 5 ones drawn. In the ABE group the overall mortality was 72% and mortality for cases occurring after 1960 was 58%. Major factors contributing to death were valvular incompetence, uncontrolled infection and embolisation. In order to reduce major complications and resulting disability in SBE it is suggested that treatment be started on clinical suspicion as soon as 5 blood cultures have been drawn over a period of 48 hours. Attempts to reduce mortality in ABE may include cardiac surgery in the acute phase.

The surgical management of bacterial endocarditis: a review

A total of 239 surgically treated patients with primary endocarditis were reviewed both from the literature and from our own experience. The age range was 10 to 74 years with a male to female ratio of 3:1. A wide variety of organisms was found. However, as a group, gram positive organisms predominate. The onset of congestive failure was the major indication for surgery. The aortic valve was predominantly involved with the mitral valve running a distant second. The hospital mortality rate was 20% and the late mortality rate was 6.7% with an overall mortality of 26.7%. The prognosis in infective endocarditis when congestive failure develops, even in the presence of antibiotic therapy, is poor (79-89% mortality). In view of this poor prognosis, an aggressive attitude with regard to early surgical intervention can greatly improve the outcome of valvular endocarditis.

Emergency aortic valve replacement in active endocarditis with the Björk-Shiley tilting disc valve prosthesis

Because of severe and intractable heart failure in three patients with infective endocarditis, an emergency replacement of the aortic valve with a Björk-Shiley prosthesis was carried out. Heart failure, which is the most common cause of death in infective endocarditis, was in these cases due to acute aortic regurgitation caused by perforation and other damage of the aortic valve. One patient died in the early postoperative period because of myocardial damage and respiratory insufficiency. The other two survived and are in relatively good condition after follow-up periods of 2 years and 6 months, respectively. The emergency replacement of incompetent valves may be a lifesaving procedure during the course of active endocarditis.

Replacement of mitral valve in active infective endocarditis

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Open heart surgery iinfeive endocarditis

Fourteen patients with bacterial endocarditis had open heart surgery. Thirteen were operated upon because of congestive heart failure, and in one the indication for surgery was persistent infection. The aortic valve alone was involved in six patients; two patients had both aortic and mitral valve endocarditis. Five patients had infection of the mitral valve, and one patient had tricuspid valve involvement. All the patients received preoperative antibiotics for a variable period.

Ten patients left the hospital and four died in the hospital. Of the 10 patients discharged, one died 9 months later of congestive heart failure. Seven patients developed valvular leaks either through the suture line or the homograft, and two deaths resulted. Nine patients are alive and in good functional status. Antibiotics were given for 5 to 10 days postoperatively; one patient, however, received antibiotics for 49 days.

Early open heart surgery is recommended in bacterial endocarditis if heart failure is progressive. Shorter postoperative antibiotic therapy is proposed once the source of residual infection is removed.

Cardiac surgery in bacterial endocarditis

Open heart surgery has been performed at the Massachusetts General Hospital in 13 patients less than 6 months after the initiation of treatment for acute or subacute bacterial endocarditis. The endocarditis involved the aortic valve in 12 cases and a mitral valve prosthesis in the other. In two patients there was concomitant rupture of chordae tendineae of the mitral valve. One patient received no preoperative antibiotics, and four were still receiving their initial course of therapy at the time of surgery. The primary indication for surgery in all cases was progressive or intractable congestive heart failure. Ten underwent replacement of the aortic valve alone, two had both aortic and mitral valves replaced, and one had a mitral prosthesis replaced.

Of the 13 patients, 10 are alive and doing well, although paraprosthetic insufficiency developed in three, two of whom required subsequent surgical repair. Three patients died, two in the early postoperative period, and one, 8 months after surgery from paraprosthetic regurgitation with hemolysis and heart failure. Antibiotics were given during and after surgery for as long as 6 weeks. In no case has recurrent sepsis been a problem.

Our experience indicates that open heart surgery, when necessitated by progressive congestive heart failure due to valve destruction, can be safely and effectively performed during or shortly after treatment of bacterial endocarditis.

Early surgical treatment of acute pneumococcal aortic valvulitis with aortic insufficiency, acquired ventricular septal defect, and aortico-right ventricular shunt

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