Cardiac surgery in HIV-positive intravenous drug addicts: influence of cardiopulmonary bypass on the progression to AIDS

Infective Endocarditis in Intravenous Drug Abusers

Infective endocarditis (IE) is one of the most severe complications in intravenous drug abusers (IVDA). IE usually involves the tricuspid valve, Staphylococcus aureus is the most common etiologic agent, and it has a relatively good prognosis. Currently, between 40% and 90% of IVDA with IE are HIV infected, and the HIV epidemic has caused a decrease in the incidence of this disease, probably due to changes in drug administration habits undertaken by addicts in order to avoid HIV transmission. This review focuses on progress made over the past few years in some aspects of IE in IVDA. The pathogenesis of tricuspid endocarditis is still unknown more than 60 years after the first series. The most important advance in antibiotic therapy is that noncomplicated S. aureus right-sided endocarditis can be successfully treated with an intravenous 2-week course of nafcillin or cloxacillin plus an aminoglycoside, although probably the aminoglycoside administration could be stopped after the first 3 to 5 days. Surgery in HIV-infected IVDA with IE does not worsen the prognosis. Considering the possibility of reinfection in IVDA, prosthetic material is usually avoided. Tricuspid valvulectomy or valve repair should be considered the technique of choice in IVDA with right-sided IE. Replacement of the tricuspid valve by a cryopreserved mitral homograft is the latest introduction into clinical practice. It provides atrioventricular competence, thereby avoiding late right heart failure. Reinfections can be treated medically with a negligible reoperation rate. Overall mortality for HIV-infected or non-HIV-infected IVDA with IE is similar. However, among HIV-infected IVDA, mortality is significantly higher in those who are most severely immunosuppressed, with CD4(+) cell counts below 200/L or with AIDS criteria.

Infective endocarditis and cardiac surgery in intravenous drug abusers and HIV-1 infected patients

Infective endocarditis (IE) is one of the most severe complications of parenteral drug abuse. The incidence of IE in intravenous drug abusers (IVDAs) is 2% to 5% per year, being responsible for 5% to 10% of the overall death rate. The prevalence of HIV infection among IVDAs with IE ranges between 30% and 70% in developed countries and HIV-infection by itself increases the risk of IE in IVDAs. The incidence of IE in IVDAs is currently decreasing in some areas, probably due to changes in drug administration habits by addicts to avoid HIV transmission. Overall, Staphylococcus aureus is the most common etiological agent, being usually sensitive to methicillin (MSSA). The tricuspid valve is the most frequently affected (60% to 70%), followed by the mitral and aortic valves (20% to 30%). HIV-positive IVDAs have a higher ratio of right-sided IE and S aureus IE than HIV-negative IVDAs. Response to antibiotic therapy is similar. Drug addicts with non-complicated MSSA right-sided IE can be treated with an i.v. short-course regimen of nafcillin or cloxacillin for 2 weeks, with or without addition of an aminoglycoside during the first 3 to 7 days. The prognosis of right-sided endocarditis is generally good; overall mortality is less than 5%, and with surgery is less than 2%. In contrast, the prognosis of left-sided IE is less favorable; mortality is 20% to 30%, and even with surgery is 15% to 25%. IE caused by GNB or fungi has the worst prognosis. Mortality between HIV-infected or non-HIV-infected IVDAs with IE is similar. However, among HIV-infected IVDAs, mortality is significantly higher in those who are most severely immunosuppressed, with CD4+ cell count < 200/microL or with AIDS criteria. Conversely, IE in HIV-infected patients who are not drug abusers is rare. The epidemiology of cardiac surgery in IVDAs and/or HIV-infected patients has changed in recent years. There is a decrease in IE and an increase of patients undergoing surgery (CABS) for coronary artery disease secondary to the hyperlipidemia and lipodystrophy induced by highly active antiretroviral therapy (HAART). Cardiac surgery in HIV-infected patients with or without IE does not worsen the prognosis because extracorporeal circulation did not affect the immune status after surgery. Morbidity and mortality seems to stay within the same range as the non-infected patients. In our experience, in the IE in HIV-infected IVDA group, the 1-year survival is 65% and the 5 and 10-year actuarial survival is 35%. For patients operated on for coronary artery disease, the 5-year survival is 100%.

Infective endocarditis in intravenous drug abusers and HIV-1 infected patients

Infective endocarditis (IE) is one of the most severe complications of parenteral drug abuse. The incidence of IE in intravenous drug abusers (IVDAs) is 2% to 5% per year, being responsible for 5% to 20% of hospital admissions and 5% to 10% of the overall death rate. IVDAs often develop recurrent IE. The prevalence of HIV infection among IVDAs with IE ranges between 30% and 70% in urban areas in developed countries. The incidence of IE in IVDAs is currently decreasing in some geographical areas, probably due to changes in drug administration habits undertaken by addicts in order to avoid HIV transmission. Overall, Staphylococcus aureus is the most common etiological agent, being in most geographical areas sensitive to methicillin (MSSA). The remainder of cases is caused by streptocococci, enterococci, GNR, Candida spp, and other less common organisms. Polymicrobial infection occurs in 2% to 5% of cases. The tricuspid valve is the most frequently affected (60% to 70%), followed by the mitral and aortic valves (20% to 30%); pulmonic valve infection is rare (< 1%). More than one valve is infected in 5% to 10% of cases. HIV-positive IVDAs have a higher ratio of right-sided IE and S. aureus IE than HIV-negative IVDAs. Response to antibiotic therapy is similar among HIV-infected or non-HIV-infected IVDAs. Drug addicts with non-complicated MSSA right-sided IE can be treated successfully with an i.v. short-course regimen of nafcillin or cloxacillin for 2 weeks, with or without addition of an aminoglycoside during the first 3 to 7 days. Surgery in HIV-infected IVDAs with IE does not worsen the prognosis. The prognosis of right-sided endocarditis is generally good; overall mortality is less than 5%, and with surgery less than 2%. In contrast, the prognosis of left-sided IE is less favorable; mortality is 20% to 30%, and even with surgery is 15% to 25%. IE caused by GNB or fungi has the worst prognosis. Mortality between HIV-infected or non-HIV-infected IVDAs with IE is similar. However, among HIV-infected IVDAs, mortality is significantly higher in those who are most severely immunosuppressed, with CD4+ cell count < 200/microL or with AIDS criteria. Finally, IE in HIV-infected patients who are not drug abusers is rare.

Coronary artery bypass grafting in a patient with human immunodeficiency virus: role of perioperative active anti-retroviral therapy

In a patient with severe ischemic heart disease and advanced human immunodeficiency virus (HIV) infection, vigorous perioperative treatment with anti-retroviral agents was given and coronary artery bypass surgery using cardiopulmonary bypass was successfully performed. This strategy could become the standard for patients with cardiovascular disease and advanced HIV infection. The following aspects of this case require further investigation: (1) lack of a reactive increase in the neutrophil count, (2) transient extreme reduction of lymphocytes, and (3) a relative decrease in the CD8+ cell ratio.