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Unusual Cardiac Complications of Staphylococcus aureus Endocarditis
Unusual Cardiac Complications of Staphylococcus aureus Endocarditis Chandra Kunavarapu, MD, Yefin Olkovsky, MD, James C. Lafferty, MD, Ali R. Homayuni, MD, Sowjanya S. Mohan, MD, Joseph McGinn, MD Augusta, Georgia; and Staten Island, New York
Bacterial endocarditis is a complex disease that is associated with significant morbidity and mortality. Staphylococcus aureus is an organism commonly responsible for acute bacterial infective endocarditis. Patients many times develop an acute fulminant infection resulting in multiple complications, even in the face of adequate therapy. We report an unusual case of S aureus acute bacterial infective endocarditis in an immunocompromised patient resulting in multiple cardiac complications, including bacterial pericarditis with effusion, mycotic aneurysm of one of the coronary arteries, a valvular vegetation leading to an aneurysmal dilatation at the mitral-aortic junction (intervalvular fibrosa), and a fistulous communication between the left ventricle and left atrium. We present detailed echocardiographic images of these anomalies, which were subsequently confirmed intraoperatively. The patient underwent open heart surgery with pericardial patch repair of the mitral-aortic intervalvular fibrosa aneurysm and fistula.
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taphylococci, as a group, cause at least 20% to 30% of infective endocarditis and in some areas may be the leading cause of infective endocarditis.1 We report rare cardiac complications of Staphylococcus aureus endocarditis in an immunocompromised patient resulting in bacterial pericarditis with effusion, an aneurysmal dilatation at the
From the Department of Cardiology, (C.K.) and Department of Infectious Disease (S.S.M), Medical College of Georgia, Augusta, Georgia; Department of Cardiology (Y.O., J.C.L., A.R.H.) and Department of Cardiothoracic Surgery (J.M.), Staten Island University Hospital, Staten Island, New York. Reprint requests: Chandra Kunavarapu, Department of Cardiology, Medical College of Georgia, 1120 15 St, BBR 6515B, Augusta, GA 30912 (E-mail: [email protected]). 0894-7317/$34.00 Copyright 2008 by the American Society of Echocardiography. doi:10.1016/j.echo.2007.06.016
Figure 1 Midesophageal long-axis view on transesophageal echocardiography demonstrating echogenic mass suggestive of endocarditis (pointer).
mitral-aortic junction (intervalvular fibrosa) (MAIVF) and a fistulous communication between the left ventricle (LV) and left atrium (LA). We present detailed echocardiographic images of these anomalies. The case not only illustrates the destructive nature of S aureus endocarditis, but also the potential for unusual complications, which require a high degree of clinical suspicion and early intervention to prevent further morbidity and mortality. CASE REPORT A 59-year-old man presented to the emergency department with symptoms of fever, chills, fatigue, and loss of appetite for 5 days. His medical history was significant for cadaveric renal transplantation 10 years before presentation, with mild renal insufficiency, type 2 diabetes mellitus, peripheral arterial disease, and a chronic right lateral foot ulcer. The patient’s medications included cyclosporine (100 mg twice a day), prednisone (5 mg once a day), insulin, and folic acid.
Figure 2 Midesophageal 5-chamber view on transesophageal echocardiography demonstrating aneurysmal dilation of mitral aortic intervalvular fibrosa (pointer). 187.e3
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Figure 3 Coronary angiogram, right anterior oblique caudal view demonstrating aneurysm at site of proximal portion of left circumflex artery. Chest radiograph revealed a widened mediastinum and a left pleural effusion. A bedside transthoracic echocardiogram revealed a large pericardial effusion with no evidence of cardiac tamponade. A pericardial window procedure was performed and 600 mL of serosanguineous fluid was drained–laboratory analysis determined it was an exudate. A biopsy specimen of the pericardium revealed acute and chronic pericarditis. Blood cultures drawn at the time of admission and pericardial fluid cultures revealed S aureus sensitive to methicillin. A transesophageal echocardiogram (TEE) was obtained and revealed low-normal LV function and a mobile density on the mitral anterior valve annulus site that
Journal of the American Society of Echocardiography February 2008
Figure 4 Midesophageal long-axis view on transesophageal echocardiography demonstrating Doppler color flow evidence of fistula from left ventricular outflow tract to left atrium; there is also evidence of mild to moderate mitral regurgitation.
was consistent with an infective vegetation. There was no clear evidence of an abscess (Figure 1). A 6-week course of antibiotics was started and a repeated TEE was performed after 4 weeks because the patient had acute worsening of symptoms (shortness of breath, fatigue). Figures 2 and 3, and Movies 1 and 2, reveal the findings. The vegetation is no longer visualized, but a large pulsatile, thin-walled echolucent space in the region of the MAIVF is seen protruding into the LA. There was a systolic expansion within the area of the MAIVF with color flow
Figure 5 Intraoperative view looking into aortic valve from above: anterior mitral valve leaflet is dehisced from aortic annulus and pink fleshy looking aneurysm is visualized. On palpation of aneurysm communication was felt into left atrium. MAIVF, Mitral aortic intervalvular fibrosa.
Kunavarapu et al
Journal of the American Society of Echocardiography Volume 21 Number 2
evidence of an eccentric high-velocity systolic jet between the LV and the LA. There was also mild mitral regurgitation, evidence of right heart volume overload, and mildly depressed global LV function. There was no evidence of abscess or pericardial effusion. A cardiac catheterization was performed that demonstrated an aneurysm at the proximal site in the left circumflex artery (Figure 4 and Movie 3) and moderate left anterior descending coronary artery disease. Based on these findings, the patient was referred for open heart surgery. Intraoperatively, an aneurysm adjacent to the noncoronary cusp of the aortic valve and the anterior mitral valve was visualized. The anterior mitral valve leaflet had dehisced from the annulus site, resulting in an aneurysm (Figure 5). In addition, on palpation of the aneurysm, a communication was felt between the LV outflow tract and the LA, confirming the TEE findings. A pericardial patch was used to close the fistula and repair the aneurysm. DISCUSSION S aureus is a leading pathogen involved in both community acquired and nosocomial infections. Staphylococcal bacteremia remains a disease with high mortality and morbidity despite appropriate antibiotic therapy. The presence of prosthetic devices and host immunosuppression increase risk for morbidity and mortality.1-3 The case presented illustrates a very unusual complication of staphylococcal acute bacterial infective endocarditis. The MAIVF is a thin area of fibrous tissue between the base of the anterior mitral leaflet and the posterior aortic root. It is an avascular region that can become secondarily infected as a result of acute bacterial infective endocarditis involving the aortic valve. Aneurysms of this region are rare, prone to rupture and embolization, and can lead to further destruction of the aortic or mitral valve apparatus.4-6 TEE has been demonstrated to be highly accurate in the diagnosis of these complications. In one series of 55 patients with aortic valve endocarditis, 11 patients
187.e5
developed either an MAIVF aneurysm or a rupture into the LA.4 In all, 8 of the 11 patients who developed these complications had a prosthetic valve endocarditis and 45% of these patients had poor outcomes (death, persistent infection, or perforation). With a high proportion of acute bacterial endocarditis caused by S aureus and in view of its highly destructive nature, clinicians should be acutely suspicious of adverse changes in a patient’s clinical course– even after institution of appropriate antibiotic therapy. TEE will be of high diagnostic value in identifying these complications. REFERENCES 1. Miro JM, Anguera I, Cabell CH, Chen AY, Stafford JA, Corey GR, et al; International Collaboration on Endocarditis Merged Database Study Group. Staphylococcus aureus native valve infective endocarditis: report of 566 episodes from the international collaboration on endocarditis merged database. Clin Infect Dis 2005;41:507-14. 2. Fowler VG Jr, Miro JM, Hoen B, Cabell CH, Abrutyn E, Rubinstein E, et al; ICE Investigators. Staphylococcus aureus endocarditis: a consequence of medical progress [erratum in JAMA 2005;294:900]. JAMA 2005;293: 3012-21. 3. Mansur AJ, Grinburg M, da Luz PL, Bellotti G. The complications of infective endocarditis: a reappraisal in the 1980s. Arch Intern Med 1992; 152:2428. 4. Karalis DG, Bansal RC, Hauck AJ, Ross JJ Jr, Applegate PM, Jutzy KR, et al. Transesophageal echocardiographic recognition of subaortic complications in aortic valve endocarditis: clinical and surgical implications. Circulation 1992;86:353-62. 5. Koch R, Kapoor A, Spencer KT. Stroke in patient with an intervalvular fibrosa pseudoaneurysm and aortic pseudoaneurysm. J Am Soc Echocardiogr 2003;16:894-6. 6. Afridi I, Apostolidou MA, Saad RM, Zoghbi WA. Pseudoaneurysms of the mitral-aortic intervalvular fibrosa: dynamic characterization using transesophageal echocardiographic and Doppler techniques. J Am Coll Cardiol 1995; 25:137-45.
Bacterial endocarditis is a complex disease that is associated with significant morbidity and mortality. Staphylococcus aureus is an organism commonly responsible for acute bacterial infective endocarditis. Patients many times develop an acute fulminant infection resulting in multiple complications, even in the face of adequate therapy. We report an unusual case of S aureus acute bacterial infective endocarditis in an immunocompromised patient resulting in multiple cardiac complications, including bacterial pericarditis with effusion, mycotic aneurysm of one of the coronary arteries, a valvular vegetation leading to an aneurysmal dilatation at the mitral-aortic junction (intervalvular fibrosa), and a fistulous communication between the left ventricle and left atrium. We present detailed echocardiographic images of these anomalies, which were subsequently confirmed intraoperatively. The patient underwent open heart surgery with pericardial patch repair of the mitral-aortic intervalvular fibrosa aneurysm and fistula.
S
taphylococci, as a group, cause at least 20% to 30% of infective endocarditis and in some areas may be the leading cause of infective endocarditis.1 We report rare cardiac complications of Staphylococcus aureus endocarditis in an immunocompromised patient resulting in bacterial pericarditis with effusion, an aneurysmal dilatation at the
From the Department of Cardiology, (C.K.) and Department of Infectious Disease (S.S.M), Medical College of Georgia, Augusta, Georgia; Department of Cardiology (Y.O., J.C.L., A.R.H.) and Department of Cardiothoracic Surgery (J.M.), Staten Island University Hospital, Staten Island, New York. Reprint requests: Chandra Kunavarapu, Department of Cardiology, Medical College of Georgia, 1120 15 St, BBR 6515B, Augusta, GA 30912 (E-mail: [email protected]). 0894-7317/$34.00 Copyright 2008 by the American Society of Echocardiography. doi:10.1016/j.echo.2007.06.016
Figure 1 Midesophageal long-axis view on transesophageal echocardiography demonstrating echogenic mass suggestive of endocarditis (pointer).
mitral-aortic junction (intervalvular fibrosa) (MAIVF) and a fistulous communication between the left ventricle (LV) and left atrium (LA). We present detailed echocardiographic images of these anomalies. The case not only illustrates the destructive nature of S aureus endocarditis, but also the potential for unusual complications, which require a high degree of clinical suspicion and early intervention to prevent further morbidity and mortality. CASE REPORT A 59-year-old man presented to the emergency department with symptoms of fever, chills, fatigue, and loss of appetite for 5 days. His medical history was significant for cadaveric renal transplantation 10 years before presentation, with mild renal insufficiency, type 2 diabetes mellitus, peripheral arterial disease, and a chronic right lateral foot ulcer. The patient’s medications included cyclosporine (100 mg twice a day), prednisone (5 mg once a day), insulin, and folic acid.
Figure 2 Midesophageal 5-chamber view on transesophageal echocardiography demonstrating aneurysmal dilation of mitral aortic intervalvular fibrosa (pointer). 187.e3
187.e4
Kunavarapu et al
Figure 3 Coronary angiogram, right anterior oblique caudal view demonstrating aneurysm at site of proximal portion of left circumflex artery. Chest radiograph revealed a widened mediastinum and a left pleural effusion. A bedside transthoracic echocardiogram revealed a large pericardial effusion with no evidence of cardiac tamponade. A pericardial window procedure was performed and 600 mL of serosanguineous fluid was drained–laboratory analysis determined it was an exudate. A biopsy specimen of the pericardium revealed acute and chronic pericarditis. Blood cultures drawn at the time of admission and pericardial fluid cultures revealed S aureus sensitive to methicillin. A transesophageal echocardiogram (TEE) was obtained and revealed low-normal LV function and a mobile density on the mitral anterior valve annulus site that
Journal of the American Society of Echocardiography February 2008
Figure 4 Midesophageal long-axis view on transesophageal echocardiography demonstrating Doppler color flow evidence of fistula from left ventricular outflow tract to left atrium; there is also evidence of mild to moderate mitral regurgitation.
was consistent with an infective vegetation. There was no clear evidence of an abscess (Figure 1). A 6-week course of antibiotics was started and a repeated TEE was performed after 4 weeks because the patient had acute worsening of symptoms (shortness of breath, fatigue). Figures 2 and 3, and Movies 1 and 2, reveal the findings. The vegetation is no longer visualized, but a large pulsatile, thin-walled echolucent space in the region of the MAIVF is seen protruding into the LA. There was a systolic expansion within the area of the MAIVF with color flow
Figure 5 Intraoperative view looking into aortic valve from above: anterior mitral valve leaflet is dehisced from aortic annulus and pink fleshy looking aneurysm is visualized. On palpation of aneurysm communication was felt into left atrium. MAIVF, Mitral aortic intervalvular fibrosa.
Kunavarapu et al
Journal of the American Society of Echocardiography Volume 21 Number 2
evidence of an eccentric high-velocity systolic jet between the LV and the LA. There was also mild mitral regurgitation, evidence of right heart volume overload, and mildly depressed global LV function. There was no evidence of abscess or pericardial effusion. A cardiac catheterization was performed that demonstrated an aneurysm at the proximal site in the left circumflex artery (Figure 4 and Movie 3) and moderate left anterior descending coronary artery disease. Based on these findings, the patient was referred for open heart surgery. Intraoperatively, an aneurysm adjacent to the noncoronary cusp of the aortic valve and the anterior mitral valve was visualized. The anterior mitral valve leaflet had dehisced from the annulus site, resulting in an aneurysm (Figure 5). In addition, on palpation of the aneurysm, a communication was felt between the LV outflow tract and the LA, confirming the TEE findings. A pericardial patch was used to close the fistula and repair the aneurysm. DISCUSSION S aureus is a leading pathogen involved in both community acquired and nosocomial infections. Staphylococcal bacteremia remains a disease with high mortality and morbidity despite appropriate antibiotic therapy. The presence of prosthetic devices and host immunosuppression increase risk for morbidity and mortality.1-3 The case presented illustrates a very unusual complication of staphylococcal acute bacterial infective endocarditis. The MAIVF is a thin area of fibrous tissue between the base of the anterior mitral leaflet and the posterior aortic root. It is an avascular region that can become secondarily infected as a result of acute bacterial infective endocarditis involving the aortic valve. Aneurysms of this region are rare, prone to rupture and embolization, and can lead to further destruction of the aortic or mitral valve apparatus.4-6 TEE has been demonstrated to be highly accurate in the diagnosis of these complications. In one series of 55 patients with aortic valve endocarditis, 11 patients
187.e5
developed either an MAIVF aneurysm or a rupture into the LA.4 In all, 8 of the 11 patients who developed these complications had a prosthetic valve endocarditis and 45% of these patients had poor outcomes (death, persistent infection, or perforation). With a high proportion of acute bacterial endocarditis caused by S aureus and in view of its highly destructive nature, clinicians should be acutely suspicious of adverse changes in a patient’s clinical course– even after institution of appropriate antibiotic therapy. TEE will be of high diagnostic value in identifying these complications. REFERENCES 1. Miro JM, Anguera I, Cabell CH, Chen AY, Stafford JA, Corey GR, et al; International Collaboration on Endocarditis Merged Database Study Group. Staphylococcus aureus native valve infective endocarditis: report of 566 episodes from the international collaboration on endocarditis merged database. Clin Infect Dis 2005;41:507-14. 2. Fowler VG Jr, Miro JM, Hoen B, Cabell CH, Abrutyn E, Rubinstein E, et al; ICE Investigators. Staphylococcus aureus endocarditis: a consequence of medical progress [erratum in JAMA 2005;294:900]. JAMA 2005;293: 3012-21. 3. Mansur AJ, Grinburg M, da Luz PL, Bellotti G. The complications of infective endocarditis: a reappraisal in the 1980s. Arch Intern Med 1992; 152:2428. 4. Karalis DG, Bansal RC, Hauck AJ, Ross JJ Jr, Applegate PM, Jutzy KR, et al. Transesophageal echocardiographic recognition of subaortic complications in aortic valve endocarditis: clinical and surgical implications. Circulation 1992;86:353-62. 5. Koch R, Kapoor A, Spencer KT. Stroke in patient with an intervalvular fibrosa pseudoaneurysm and aortic pseudoaneurysm. J Am Soc Echocardiogr 2003;16:894-6. 6. Afridi I, Apostolidou MA, Saad RM, Zoghbi WA. Pseudoaneurysms of the mitral-aortic intervalvular fibrosa: dynamic characterization using transesophageal echocardiographic and Doppler techniques. J Am Coll Cardiol 1995; 25:137-45.