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Vegetectomy: An alternative surgical treatment for infective endocarditis of the atrioventricular valves in drug addicts
J THoRAc CARDIOVASC SURG 1988;95:857-61
Vegetectomy: An alternative surgical treatment for infective endocarditis of the atrioventricular valves in drug addicts The case of a patient in whom two separate episodes of infective endocarditis were treated by excision of the infected vegetation ("vegetectomy") is reported. In carefully selected patients, early conservative operation may preserve the native valve and avoid the hazards of anticoagulative medication and prosthetic endocarditis in habitual drug abusers.
Clifford F. Hughes, MB, BS, FRACS, FACS, and Neil Noble, MB, BS, FRACP, Concord and Camperdown, Australia
Infective endocarditis is one of the most serious complications of intravenous drug abuse. The pattern of the disease differs from its course in nonabusers in that the right side of the heart is more commonly involved, there is an unusually low incidence of preexisting valve disease, and the clinical picture is dominated by repeated episodes of septic emboli. I Although the majority of the patients with right-sided lesions respond to medical therapy, some patients will require operation for uncontrolled sepsis, recurrent emboli, or cardiac failure.':' Valve replacement in addicts is complicated by poor patient compliance and recurrent endocarditis on the prosthetic valve." 5 In the tricuspid position, the infected valve may be excised, although some of these patients will require later valve replacement." Most left-sided lesions have necessitated valve replacement.v' We report the case of a drug abuser in whom two separate episodes of staphylococcal endocarditis (one tricuspid, one mitral) were treated by simple excision of the vegetation with preservation of the native valve.
Case report A 31-year-old female heroin addict was admitted in June 1985; she had had fever, headache, and pain in the left side of
From the Department of Cardiothoracic Surgery, Repatriation General Hospital, Concord, NSW, and Cardiothoracic Surgical Unit, Royal Prince Alfred Hospital, Camperdown, NSW, Australia. Received for publication Feb. 5, 1987. Accepted for publication April 3, 1987. Address for reprints: Dr. C. F. Hughes, FRACS, Cardiothoracic Surgical Unit, Royal Prince Alfred Hospital, Missenden Road, Camperdown, NSW, 2050, Australia.
the chest for 2 weeks. Previously, in 1980 and 1981, staphylococcal bacterial endocarditis had been treated conservatively. On both occasions she was noted to have tricuspid regurgitation, but no vegetations were detected on echocardiography. On examination she was in a toxic condition with the hallmarks of intravenous heroin addiction and severe tricuspid regurgitation. The chest x-ray film was normal but the echocardiogram showed a mobile vegetation on the posterior leaflet of the tricuspid valve (Fig. I). Staphylococcus aureus sensitive to penicillin grew in blood cultures taken on admission. The patient had had multiple drug allergies and was treated initially with cephalothin and then erythromycin and fusidic acid. Her fever began to settle, but subsequent chest x-ray films showed progressive cardiac enlargement and the serial development of bilateral foci consistent with pulmonary embolism. Serial echocardiograms showed a significant increase in the vegetation size. Operation was advised because of recurrent emboli, progressive right ventricular failure, and the development of a hemolytic anemia. At operation, the tricuspid anulus was widely dilated. There was a large polypoid vegetation attached to the free margin of the posterior leaflet by a thin pedicle. The rest of the valve apparatus was normal (Fig. 2). The vegetation was excised with a few millimeters of the free edge of the leaflet, and a Carpentier ring was inserted. Although the patient remained afebrile, antibiotic therapy was continued for 4 weeks, and the patient was discharged in good condition 32 days after operation (Fig. 3). An echocardiogram at I month showed no vegetations. A soft pansystolic murmur at the right sternal edge was the only evidence of mild tricuspid regurgitation. In March 1986, the patient returned with a 4-week history of fever, weight loss (28 pounds), pain in the right side of the chest, and shortness of breath. She was febrile (39.8° C) with fresh puncture marks and bruising over both arms, splinter hemorrhages under her nails, and a grade III pansystolic murmur at the left sternal edge. Gross left ventricular failure was diagnosed. Blood cultures grew a Staphylococcus aureus sensitive to fusidic acid and erythromycin. The chest x-ray film
857
The Journal of
8 5 8 Hughes and Noble
Thoracic and Cardiovascular Surgery
Fig. I. Two-dimensional echocardiogram showing vegetation on tricuspid valve.
Fig. 2. Large polypoid vegetation arising from dilated tricuspid valve. confirmed congestive cardiac failure, and the echocardiogram showed a large polypoid vegetation on the posterior leaflet of the mitral valve. The tricuspid valve appeared normal (Fig. 4). Because of our encouraging previous experience, and in the face of catastrophic cardiac failure, we elected to proceed with urgent operation with a view of valve conservation. At operation, a small polypoid vegetation was found on the left side of the interatrial septum. There was a large polypoid vegetation attached to the free margin of the posterior mitral leaflet (Figs. 5 and 6). Both leaflets and all chordae were normal. Both vegetations were simply lifted off by the pedicle and the site of attachment scraped with a curette. The mitral valve then appeared to be fully competent. There was no mitral
regurgitation postoperatively. The tricuspid valve was not visualized. The patient was afebrile from the day of operation but continued to receive fusidic acid, gentamicin, and erythromycin for an additional 6 weeks. She was discharged in good condition on day 44. The patient remains under the surveillance of the Drug and Rehabilitation Service of another hospital. She continues on a supervised methadone program but has resumed her habit, at least sporadically.
Discussion
Infective endocarditis has become a major problem among intravenous drug abusers and is responsible for
Volume 95 Number 5
859
Vegetectomy for infective endocarditis
May 1988
39
• Cephelothin
~
Tricuspid Endocarditis
Fusidic Acid Erythromycin
Cardiac Failure
38
P E R A T
TempOC
f
I
o
Pulmonary Embolus
36
N
f Ec ho -5
-4
-3
-2
-1
o
Days
2
3
4
5
2
3
4
5
Mitral Endocarditis
Gentam ic;n ] Erythromycin -
39
+
FU81dic: Acid
o
38
P E R
TempoC 37
o
.
A
T I
o
36
N
f
Echo
-5
-4
-3
-2
Echo = 2 DtmenSM>flal Echocardiooraphy
-1
o
Days
Fig. 3. Clinical course of two episodes of endocarditis.
Fig. 4. Two-dimensional echocardiogram showing vegetation on mitral valve.
14% of all deaths in this group.' The tricuspid valve, usually an uncommon site of endocarditis, is involved in between 40% and 100% of addicts with endocarditis. 3,4 Staphylococcus aureus is the most common organism found in addicts although Pseudomonas has been the
major pathogen in some.v' Combined M-mode and two-dimensional echocardiography may detect vegetations in up to 80% of patients with infective endocarditis, although the sensitivity of this technique remains unknown." Two-dimensional echocardiography appears
The Journal of
860
Thoracic and Cardiovascular Surgery
Hughes and Noble
Fig. 5. Small vegetation on interatrial septum.
"
Fig. 6. Large lobulated vegetation arising from posterior leaflet on mitral valve. significantly better than M-mode echocardiography. The echocardiographic dimensions of the vegetations correlate well with the surgical specimens.'? In one study, 10 patients who failed to respond to medical therapy all had vegetations larger than 1 em on echocardiography and at operation.' However, other studies have not shown M-mode or two-dimensional echocardiographic features to be predictive of outcome. 10 Whereas most authors have noted that tricuspid valve endocarditis responds well to conventional antibiotic therapy, those patients with severe cardiac decompensa-
tion have a mortality rate of 50% to 90% unless operated on.n 10-12 In one study, 93% of drug addicts required operation during the active phase of infection for unresolved sepsis, recurrent emboli, or cardiac failure. I] In contradistinction to most patients with infective endocarditis, addicts usually have normal valves before the infection occurs. 14, 15 Our patient was typical of these reports: Staphylococcus aureus grew in the blood and there was a demonstrable 1.5 em tricuspid vegetation, right-sided heart failure, and recurrent pulmonary emboli despite optimal medical therapy. Furthermore, apart from annular
Volume 95 Number 5 May 1988
dilatation, the valve leaflets appeared normal. The vegetation was truly polypoid and total preservation of the valve seemed much preferable to either a prosthesis or valvulectomy. Arbulu and associates" first performed a successful valvulectomy in 1970 and Arbula and Asfaw" have since reported a series of 61 patients (52 of whom were addicts) with a 30-day mortality rate of 6% and another seven late deaths. Eleven patients required subsequent insertion of a prosthesis. Stern and associates) reported on 10 patients (all addicts) in whom tricuspid valve replacement was used when medical treatment failed. All 10 left the hospital, but bioprosthetic infection developed in the three addicts who returned to the habit, and two of them died.' While immediate valve replacement can be performed with a low mortality rate,3.13.17 the risk of poorly controlled anticoagulation therapy and reintroduced sepsis remain a problem in the addicted population. Chandraratna and co-workers" first described the simple excision of a vegetation on a tricuspid valve in 1978. One other case, that of a 16-year-old male patient with acute fulminant ulcerative colitis, has been described." Weare not aware of a similar procedure having been done on the mitral valve nor of any case in which sequential "vegetectomies" have been done. Management of the second episode of our patient was influenced by the sure knowledge that the patient would return to intravenous drug abuse. Encouraged by our first experience with the patient and by the reports in the literature, operation was undertaken with a view to repeating the vegetectomy with or without annuloplasty. However, the value was fully competent after excision of the vegetation, and we have assumed that the mitral regurgitation was a mechanical effect of this very large vegetation. To our delight and to the patient's good fortune such a procedure was possible. The patient remains free of further bacterial endocarditis, at least in the short term. We do not propose that all, or even many, patients will be amenable to early vegetectomy. However, we would suggest that, where indicated, early operation and vegetectomy may have even greater benefits than have been previously appreciated, including preservation of the normal, native valve, preservation of normal hemodynamic function, abolition of the risks of anticoagulative medication, and abolition of the risks of prosthetic endocarditis. REFERENCES I. Conway N. Endocarditis in heroin addicts. Br Heart J 1969;31:543-5. 2. Graham DY, Real GJ, Martin R, Morton J, Kennedy
Vegetectomy for infective endocarditis
86 1
JH. Infective endocarditis in drug addicts: experiences with medical and surgical treatment. Circulation 1973; 48(Pt 3):III37-41. 3. Stern HJ, Sisto DA, Strom JA, Soeira R, Jones SR, Frater RWM. Immediate tricuspid valve replacement for endocarditis. J THoRAc CARDIOVASC SURG 1986;91: 163-7. 4. Boyd AD, Spencer FC, Isom OW, et al. Infective endocarditis: an analysis of 54 surgically treated patients. J THORAC CARDIOVASC SURG 1977;73:23-30. 5. Mammana RB, Levitsky S, Sernaque 0, Beckman CB, Silverman NA. Valve replacement for left sided endocarditis in drug addicts. Ann Thorac Surg 1983;35:436-41. 6. Arbulu A, Asfaw I. Tricuspid valvulectomy without prosthetic replacement: ten years of clinical experience. J THoRAc CARDIOVASC SURG 1981;82:684-91. 7. Sapira JD. The narcotic addict as a medical patient. Am J Med 1968;45:555-8. 8. Dreyer NP, Fields BN. Heroin-associated infective endocarditis: a report of 28 cases. Ann Intern Med 1973; 78:699-702. 9. Panadis IP, Kotler MN, Mintz GS, Segal BL, Ross JJ. Right heart endocarditis: clinical and echocardiographic features. Am Heart J 1984;107:759-64. 10. Ginzton LE, Siegel RJ, Criley JM: Natural history of tricuspid valve endocarditis: a two dimensional echocardiographic study. Am J Cardiol 1982;49: 1853-9. II. Rapaport E. The changing role of surgery in the management of infective endocarditis [Editorial]. Circulation 1978;58:598-9. 12. Menda KB, Gorbach SL. Favourable experience with bacterial endocarditis in heroin addicts. Ann Intern Med 1973;78:25-32. 13. Nelson RT, Harley DP, French W J, Bayer AS. Favourable ten-year experience with valve procedures for active infective endocarditis. J THoRAc CARDIOVASC SURG 1984; 87:493-502. 14. Banks T, Fletcher R, Ali N. Infective endocarditis in heroin addicts. Am J Med 1973;55:444-51. 15. Roberts WC, Buchbinder NA. Right-sided valvular infective endocarditis: a clinicopathologic study of twelve necropsy patients. Am J Med 1972;53:7-19. 16. Arbulu A, Thoms NW, Chiscan A, Wilson RF. Total tricuspid valvulectomy without replacement in the treatment of Pseudomonas endocarditis. Surg Forum 1971; 22:162-4. 17. Jung JY, Soab SB, Almond CH. The case for early surgical treatment of left-sided primary infective endocarditis: a collective review. J THORAC CARDIOVASC SURG 1975;70:509-18. 18. Chandraratna PAN, Reagan RB, Imaizumi T, Langevin E, Elkins RC. Infective endocarditis cured by resection of a tricuspid valve vegetation. Ann Intern Med 1978; 89:517-9. 19. Jagger JD, McCaughan BC, Pawsey CP, Bradbury R. Tricuspid valve endocarditis cured by excision of a single vegetation. Am Heart J 1986; 112:626-7.
Vegetectomy: An alternative surgical treatment for infective endocarditis of the atrioventricular valves in drug addicts The case of a patient in whom two separate episodes of infective endocarditis were treated by excision of the infected vegetation ("vegetectomy") is reported. In carefully selected patients, early conservative operation may preserve the native valve and avoid the hazards of anticoagulative medication and prosthetic endocarditis in habitual drug abusers.
Clifford F. Hughes, MB, BS, FRACS, FACS, and Neil Noble, MB, BS, FRACP, Concord and Camperdown, Australia
Infective endocarditis is one of the most serious complications of intravenous drug abuse. The pattern of the disease differs from its course in nonabusers in that the right side of the heart is more commonly involved, there is an unusually low incidence of preexisting valve disease, and the clinical picture is dominated by repeated episodes of septic emboli. I Although the majority of the patients with right-sided lesions respond to medical therapy, some patients will require operation for uncontrolled sepsis, recurrent emboli, or cardiac failure.':' Valve replacement in addicts is complicated by poor patient compliance and recurrent endocarditis on the prosthetic valve." 5 In the tricuspid position, the infected valve may be excised, although some of these patients will require later valve replacement." Most left-sided lesions have necessitated valve replacement.v' We report the case of a drug abuser in whom two separate episodes of staphylococcal endocarditis (one tricuspid, one mitral) were treated by simple excision of the vegetation with preservation of the native valve.
Case report A 31-year-old female heroin addict was admitted in June 1985; she had had fever, headache, and pain in the left side of
From the Department of Cardiothoracic Surgery, Repatriation General Hospital, Concord, NSW, and Cardiothoracic Surgical Unit, Royal Prince Alfred Hospital, Camperdown, NSW, Australia. Received for publication Feb. 5, 1987. Accepted for publication April 3, 1987. Address for reprints: Dr. C. F. Hughes, FRACS, Cardiothoracic Surgical Unit, Royal Prince Alfred Hospital, Missenden Road, Camperdown, NSW, 2050, Australia.
the chest for 2 weeks. Previously, in 1980 and 1981, staphylococcal bacterial endocarditis had been treated conservatively. On both occasions she was noted to have tricuspid regurgitation, but no vegetations were detected on echocardiography. On examination she was in a toxic condition with the hallmarks of intravenous heroin addiction and severe tricuspid regurgitation. The chest x-ray film was normal but the echocardiogram showed a mobile vegetation on the posterior leaflet of the tricuspid valve (Fig. I). Staphylococcus aureus sensitive to penicillin grew in blood cultures taken on admission. The patient had had multiple drug allergies and was treated initially with cephalothin and then erythromycin and fusidic acid. Her fever began to settle, but subsequent chest x-ray films showed progressive cardiac enlargement and the serial development of bilateral foci consistent with pulmonary embolism. Serial echocardiograms showed a significant increase in the vegetation size. Operation was advised because of recurrent emboli, progressive right ventricular failure, and the development of a hemolytic anemia. At operation, the tricuspid anulus was widely dilated. There was a large polypoid vegetation attached to the free margin of the posterior leaflet by a thin pedicle. The rest of the valve apparatus was normal (Fig. 2). The vegetation was excised with a few millimeters of the free edge of the leaflet, and a Carpentier ring was inserted. Although the patient remained afebrile, antibiotic therapy was continued for 4 weeks, and the patient was discharged in good condition 32 days after operation (Fig. 3). An echocardiogram at I month showed no vegetations. A soft pansystolic murmur at the right sternal edge was the only evidence of mild tricuspid regurgitation. In March 1986, the patient returned with a 4-week history of fever, weight loss (28 pounds), pain in the right side of the chest, and shortness of breath. She was febrile (39.8° C) with fresh puncture marks and bruising over both arms, splinter hemorrhages under her nails, and a grade III pansystolic murmur at the left sternal edge. Gross left ventricular failure was diagnosed. Blood cultures grew a Staphylococcus aureus sensitive to fusidic acid and erythromycin. The chest x-ray film
857
The Journal of
8 5 8 Hughes and Noble
Thoracic and Cardiovascular Surgery
Fig. I. Two-dimensional echocardiogram showing vegetation on tricuspid valve.
Fig. 2. Large polypoid vegetation arising from dilated tricuspid valve. confirmed congestive cardiac failure, and the echocardiogram showed a large polypoid vegetation on the posterior leaflet of the mitral valve. The tricuspid valve appeared normal (Fig. 4). Because of our encouraging previous experience, and in the face of catastrophic cardiac failure, we elected to proceed with urgent operation with a view of valve conservation. At operation, a small polypoid vegetation was found on the left side of the interatrial septum. There was a large polypoid vegetation attached to the free margin of the posterior mitral leaflet (Figs. 5 and 6). Both leaflets and all chordae were normal. Both vegetations were simply lifted off by the pedicle and the site of attachment scraped with a curette. The mitral valve then appeared to be fully competent. There was no mitral
regurgitation postoperatively. The tricuspid valve was not visualized. The patient was afebrile from the day of operation but continued to receive fusidic acid, gentamicin, and erythromycin for an additional 6 weeks. She was discharged in good condition on day 44. The patient remains under the surveillance of the Drug and Rehabilitation Service of another hospital. She continues on a supervised methadone program but has resumed her habit, at least sporadically.
Discussion
Infective endocarditis has become a major problem among intravenous drug abusers and is responsible for
Volume 95 Number 5
859
Vegetectomy for infective endocarditis
May 1988
39
• Cephelothin
~
Tricuspid Endocarditis
Fusidic Acid Erythromycin
Cardiac Failure
38
P E R A T
TempOC
f
I
o
Pulmonary Embolus
36
N
f Ec ho -5
-4
-3
-2
-1
o
Days
2
3
4
5
2
3
4
5
Mitral Endocarditis
Gentam ic;n ] Erythromycin -
39
+
FU81dic: Acid
o
38
P E R
TempoC 37
o
.
A
T I
o
36
N
f
Echo
-5
-4
-3
-2
Echo = 2 DtmenSM>flal Echocardiooraphy
-1
o
Days
Fig. 3. Clinical course of two episodes of endocarditis.
Fig. 4. Two-dimensional echocardiogram showing vegetation on mitral valve.
14% of all deaths in this group.' The tricuspid valve, usually an uncommon site of endocarditis, is involved in between 40% and 100% of addicts with endocarditis. 3,4 Staphylococcus aureus is the most common organism found in addicts although Pseudomonas has been the
major pathogen in some.v' Combined M-mode and two-dimensional echocardiography may detect vegetations in up to 80% of patients with infective endocarditis, although the sensitivity of this technique remains unknown." Two-dimensional echocardiography appears
The Journal of
860
Thoracic and Cardiovascular Surgery
Hughes and Noble
Fig. 5. Small vegetation on interatrial septum.
"
Fig. 6. Large lobulated vegetation arising from posterior leaflet on mitral valve. significantly better than M-mode echocardiography. The echocardiographic dimensions of the vegetations correlate well with the surgical specimens.'? In one study, 10 patients who failed to respond to medical therapy all had vegetations larger than 1 em on echocardiography and at operation.' However, other studies have not shown M-mode or two-dimensional echocardiographic features to be predictive of outcome. 10 Whereas most authors have noted that tricuspid valve endocarditis responds well to conventional antibiotic therapy, those patients with severe cardiac decompensa-
tion have a mortality rate of 50% to 90% unless operated on.n 10-12 In one study, 93% of drug addicts required operation during the active phase of infection for unresolved sepsis, recurrent emboli, or cardiac failure. I] In contradistinction to most patients with infective endocarditis, addicts usually have normal valves before the infection occurs. 14, 15 Our patient was typical of these reports: Staphylococcus aureus grew in the blood and there was a demonstrable 1.5 em tricuspid vegetation, right-sided heart failure, and recurrent pulmonary emboli despite optimal medical therapy. Furthermore, apart from annular
Volume 95 Number 5 May 1988
dilatation, the valve leaflets appeared normal. The vegetation was truly polypoid and total preservation of the valve seemed much preferable to either a prosthesis or valvulectomy. Arbulu and associates" first performed a successful valvulectomy in 1970 and Arbula and Asfaw" have since reported a series of 61 patients (52 of whom were addicts) with a 30-day mortality rate of 6% and another seven late deaths. Eleven patients required subsequent insertion of a prosthesis. Stern and associates) reported on 10 patients (all addicts) in whom tricuspid valve replacement was used when medical treatment failed. All 10 left the hospital, but bioprosthetic infection developed in the three addicts who returned to the habit, and two of them died.' While immediate valve replacement can be performed with a low mortality rate,3.13.17 the risk of poorly controlled anticoagulation therapy and reintroduced sepsis remain a problem in the addicted population. Chandraratna and co-workers" first described the simple excision of a vegetation on a tricuspid valve in 1978. One other case, that of a 16-year-old male patient with acute fulminant ulcerative colitis, has been described." Weare not aware of a similar procedure having been done on the mitral valve nor of any case in which sequential "vegetectomies" have been done. Management of the second episode of our patient was influenced by the sure knowledge that the patient would return to intravenous drug abuse. Encouraged by our first experience with the patient and by the reports in the literature, operation was undertaken with a view to repeating the vegetectomy with or without annuloplasty. However, the value was fully competent after excision of the vegetation, and we have assumed that the mitral regurgitation was a mechanical effect of this very large vegetation. To our delight and to the patient's good fortune such a procedure was possible. The patient remains free of further bacterial endocarditis, at least in the short term. We do not propose that all, or even many, patients will be amenable to early vegetectomy. However, we would suggest that, where indicated, early operation and vegetectomy may have even greater benefits than have been previously appreciated, including preservation of the normal, native valve, preservation of normal hemodynamic function, abolition of the risks of anticoagulative medication, and abolition of the risks of prosthetic endocarditis. REFERENCES I. Conway N. Endocarditis in heroin addicts. Br Heart J 1969;31:543-5. 2. Graham DY, Real GJ, Martin R, Morton J, Kennedy
Vegetectomy for infective endocarditis
86 1
JH. Infective endocarditis in drug addicts: experiences with medical and surgical treatment. Circulation 1973; 48(Pt 3):III37-41. 3. Stern HJ, Sisto DA, Strom JA, Soeira R, Jones SR, Frater RWM. Immediate tricuspid valve replacement for endocarditis. J THoRAc CARDIOVASC SURG 1986;91: 163-7. 4. Boyd AD, Spencer FC, Isom OW, et al. Infective endocarditis: an analysis of 54 surgically treated patients. J THORAC CARDIOVASC SURG 1977;73:23-30. 5. Mammana RB, Levitsky S, Sernaque 0, Beckman CB, Silverman NA. Valve replacement for left sided endocarditis in drug addicts. Ann Thorac Surg 1983;35:436-41. 6. Arbulu A, Asfaw I. Tricuspid valvulectomy without prosthetic replacement: ten years of clinical experience. J THoRAc CARDIOVASC SURG 1981;82:684-91. 7. Sapira JD. The narcotic addict as a medical patient. Am J Med 1968;45:555-8. 8. Dreyer NP, Fields BN. Heroin-associated infective endocarditis: a report of 28 cases. Ann Intern Med 1973; 78:699-702. 9. Panadis IP, Kotler MN, Mintz GS, Segal BL, Ross JJ. Right heart endocarditis: clinical and echocardiographic features. Am Heart J 1984;107:759-64. 10. Ginzton LE, Siegel RJ, Criley JM: Natural history of tricuspid valve endocarditis: a two dimensional echocardiographic study. Am J Cardiol 1982;49: 1853-9. II. Rapaport E. The changing role of surgery in the management of infective endocarditis [Editorial]. Circulation 1978;58:598-9. 12. Menda KB, Gorbach SL. Favourable experience with bacterial endocarditis in heroin addicts. Ann Intern Med 1973;78:25-32. 13. Nelson RT, Harley DP, French W J, Bayer AS. Favourable ten-year experience with valve procedures for active infective endocarditis. J THoRAc CARDIOVASC SURG 1984; 87:493-502. 14. Banks T, Fletcher R, Ali N. Infective endocarditis in heroin addicts. Am J Med 1973;55:444-51. 15. Roberts WC, Buchbinder NA. Right-sided valvular infective endocarditis: a clinicopathologic study of twelve necropsy patients. Am J Med 1972;53:7-19. 16. Arbulu A, Thoms NW, Chiscan A, Wilson RF. Total tricuspid valvulectomy without replacement in the treatment of Pseudomonas endocarditis. Surg Forum 1971; 22:162-4. 17. Jung JY, Soab SB, Almond CH. The case for early surgical treatment of left-sided primary infective endocarditis: a collective review. J THORAC CARDIOVASC SURG 1975;70:509-18. 18. Chandraratna PAN, Reagan RB, Imaizumi T, Langevin E, Elkins RC. Infective endocarditis cured by resection of a tricuspid valve vegetation. Ann Intern Med 1978; 89:517-9. 19. Jagger JD, McCaughan BC, Pawsey CP, Bradbury R. Tricuspid valve endocarditis cured by excision of a single vegetation. Am Heart J 1986; 112:626-7.