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Right Coronary Artery Septic Embolization Secondary to Aerococcus urinae Native Mitral Valve Endocarditis
Right Coronary Artery Septic Embolization Secondary to Aerococcus urinae Native Mitral Valve Endocarditis Kunal D. Kotkar, MS, MCh, Sameh M. Said, MD, Hector Michelena, MD, Brendan Wanta, MD, Maria D. Fritock, MD, and Larry M. Baddour, MD Divisions of Cardiovascular Surgery, Cardiovascular Diseases, Infectious Diseases, and Cardiothoracic Anesthesia, Mayo Clinic, Rochester, Minnesota
Septic embolization to the coronary arteries from infective endocarditis is a rare occurrence. Appropriate treatment is not yet fully determined. We report a case of mitral valve endocarditis due to Aerococcus urinae presenting as acute inferior myocardial infarction. (Ann Thorac Surg 2016;102:e295–7) Ó 2016 by The Society of Thoracic Surgeons
I
nfective endocarditis (IE) has a high incidence of systemic embolization, most commonly affecting the central nervous system and arising within the first 2 weeks of antimicrobial therapy. Septic embolization to the coronary arteries is a rare complication [1]. Several management strategies exist including either percutaneous or surgical options. Aerococcus urinae (A. urinae) was initially defined as a human pathogen in 1992 and is characterized as a gram-positive, catalase-negative coccus resembling Staphylococcus. Although generally considered to harbor limited virulence, it can cause severe and fatal bloodstream infections. Aerococcus species as a cause of IE, itself is uncommon among the general population [2]. We report a 54 year-old patient with acute mitral valve (MV) IE due to A. urinae who presented with acute myocardial infarction. A 54 year-old farmer presented with persistent fever and chills despite antibiotic treatment. Initial evaluation showed ST-segment elevation in the inferior leads with elevated troponins. Echocardiography revealed severe MV regurgitation and large mobile vegetations (Fig 1A). There was evidence of severe right ventricular dysfunction and severe tricuspid valve (TV) regurgitation. CT scan of head, chest, and abdomen showed bilateral pulmonary nodules suspicious of septic emboli and splenic infarcts with no evidence of acute intracranial pathology. Clinical examination revealed phimosis with meatal stenosis. Decision was made to proceed with surgery due to the presence of heart failure and risk of embolization. Preoperative coronary angiogram showed 100% occlusion of proximal right coronary artery (RCA) (Fig 1B). The
Accepted for publication Feb 18, 2016. Address correspondence to Dr Said, Mayo Clinic, 200 1st St SW, Rochester, MN 55905; email: [email protected].
Ó 2016 by The Society of Thoracic Surgeons Published by Elsevier
left anterior descending and circumflex arteries were free of any significant stenosis. Through a median sternotomy, and aortic and bicaval cannulation, the MV was approached through a vertical transseptal approach. Large vegetations were identified on the posterior leaflet of the MV with marked thickening of the anterior leaflet (Fig 2A). There were no vegetations on the TV. The RCA was dissected in the atrioventricular groove down to the acute margin of the heart. An arteriotomy was made along the long axis of the RCA where we identified a 2-cm-long embolus (Figs 2B, 2C). The rest of the RCA was clean and free of any disease. MV replacement with 31 mm SJM Epic valve (St. Jude Medical, Inc, St. Paul, MN), TV repair with 28 mm Carbomedics annuloplasty ring (Sorin-CarboMedics, Austin, TX), and RCA embolectomy with a saphenous vein patch arterioplasty (Fig 2D) were performed. A reversed saphenous vein graft bypass to the distal RCA was added. Postoperative recovery was uneventful and patient was discharged from the hospital 6 days later. CT coronary angiogram prior to discharge showed occlusion of the proximal native RCA where embolectomy was performed, however, the saphenous vein graft to distal RCA bypass was widely patent (Fig 3). Preoperative blood cultures grew A. urinae. The vegetations on the MV and the culture from the RCA embolus were positive for A. urinae. Patient was discharged on ampicillin monotherapy for 6 weeks.
Comment Systemic embolization in IE is very common (incidence of 22% to 50%), most commonly to the central nervous system. However embolization to coronary arteries is a rare event (incidence 2.9% to 10.6%) [3]. The majority of these involve the left coronary system, probably due to the preferential flow related to aortic valve morphology [4]. Aerococcus species as a cause of IE [2] is extremely rare. Older males predominated in a recent review and several had urologic diagnoses, with the most common urologic condition being benign prostate hyperplasia. Of the reported cases of Aerococcus species infections, IE complications were common in 24 cases [5]; indeed, 21% underwent valve surgery, and 46% of the overall group died. Clearly, in the current case report that describes phimosis and urethral meatal stenosis, it is reasonable that the latter could have predisposed to at least urinary colonization with A. urinae, although a urine culture prior to an IE diagnosis was negative. Management of patients with coronary embolization in the setting of IE is controversial. Options available include catheter-based interventions such as thrombolysis, percutaneous transluminal coronary angioplasty (PTCA) with or without stent placement, and catheter aspiration or surgery. Thrombolysis is often contraindicated in these settings due to the higher risk of intracerebral hemorrhage [6]. 0003-4975/$36.00 http://dx.doi.org/10.1016/j.athoracsur.2016.02.069
e296
CASE REPORT KOTKAR ET AL RIGHT CORONARY ARTERY EMBOLISM IN ACUTE INFECTIVE ENDOCARDITIS
Ann Thorac Surg 2016;102:e295–7
Fig 1. (A) Transthoracic parasternal long-axis systolic zoomed still frame shows a large vegetation (arrow) prolapsing into the left atrium in systole. (B) Left anterior oblique cranial projection coronary angiogram showing abrupt cutoff at mid– right coronary artery level.
PTCA with stent placement may be associated with development of mycotic aneurysms, failure to achieve coronary patency and distal embolization. The use of drug eluting stents predisposes to a higher risk of reinfection as compared to bare metal stents due to their immunomodulatory properties [7]. Aspiration catheters are an attractive option; however they are rarely effective in isolation. Surgery represents an ideal option due to the ability to eradicate the infection, and management of all associated valve pathology. Surgical coronary embolectomy through a direct coronary arteriotomy is well-recognized technique [6].
Fig 2. (A) Pathological specimen of excised mitral leaflet with vegetations. (B) Operative image showing right coronary artery (RCA) opened up showing the embolus in situ. (C) Pathological specimen on the embolus. (D) Completed saphenous vein patch arterioplasty of RCA.
The indications for surgery in our case were clear; however, the timing and the management strategy for the RCA were not. Reversed saphenous venous graft bypass to the distal RCA alone was associated with a risk of leaving potentially infected material within the RCA. Septic emboli have been known to cause mycotic aneurysms in coronary arteries [8]. An infected embolus in a 100% blocked coronary artery (as in our case) represents a source of infection, which has very poor antibiotic penetration. This is further supported by the fact the coronary embolus grew A. urinae after the blood cultures had turned negative.
Ann Thorac Surg 2016;102:e295–7
CASE REPORT KOTKAR ET AL RIGHT CORONARY ARTERY EMBOLISM IN ACUTE INFECTIVE ENDOCARDITIS
e297
Is additional surgical revascularization necessary after embolectomy? This is a difficult question to answer due to the limited data in literature and the rarity of such cases. In our case, despite completely removing the RCA embolus, we felt that additional bypass with a vein graft would provide additional safety in case of reocclusion of the RCA. Our treatment plan proved to be effective as the predismissal CT showed thrombosis at the embolectomy site with widely patent bypass graft.
References
Fig 3. Postoperative computed tomography coronary angiogram showing thrombosed mid–right coronary artery (RCA) (yellow arrow) with patent saphenous venous graft to RCA (blue arrow).
Performing an embolectomy alone is also an option, as the proximal and mid RCA are easily accessible for surgical embolectomy. However there is always a possibility that the embolectomy site will develop thrombosis due to endothelial disruption. Also there is no logical method of confirming completion of embolectomy as distal showering of emboli during the procedure is possible.
1. Baek M-J, Kim HK, Yu CW, Na CW. Mitral valve surgery with surgical embolectomy for mitral valve endocarditis complicated by septic coronary embolism. Eur J Cardiothorac Surg 2008;33:116–8. 2. DeSimone DC, Tleyjeh IM, Correa de Sa DD, et al. Temporal trends in infective endocarditis epidemiology from 2007 to 2013 in Olmsted County. MN. Am Heart J 2015;170:830–6. 3. Manzano MC, Vilacosta I, San Roman JA, et al. [Acute coronary syndrome in infective endocarditis]. Rev Esp Cardiol 2007;60:24–31. 4. Prizel KR, Hutchins GM, Bulkley BH. Coronary artery embolism and myocardial infarction, a clinicopathologic study of 55 patients. Ann Intern Med 1978;88:155–61. 5. Rasmussen M. Aerococci and aerococcal infections. J Infect 2013;66:467–74. 6. Singh M, Mishra A, Kaluski E. Acute ST-elevation myocardial infarction due to septic embolism: A case report and review of management options. Cathet Cardiovasc Interv 2015;85: E166–71. 7. Patel AJ, Mehta RM, Gandhi DB, et al. Coronary aneurysm and purulent pericardial effusion: Old disease with an unusual cause. Ann Thorac Surg 2013;95:1791–3. 8. Reece IJ, Al Tareif H, Tolia J, Saeed FA. Mycotic aneurysm of the left anterior descending coronary artery after aortic endocarditis. A case report and brief review of the literature. Tex Heart Inst J 1994;21:231–5.
Septic embolization to the coronary arteries from infective endocarditis is a rare occurrence. Appropriate treatment is not yet fully determined. We report a case of mitral valve endocarditis due to Aerococcus urinae presenting as acute inferior myocardial infarction. (Ann Thorac Surg 2016;102:e295–7) Ó 2016 by The Society of Thoracic Surgeons
I
nfective endocarditis (IE) has a high incidence of systemic embolization, most commonly affecting the central nervous system and arising within the first 2 weeks of antimicrobial therapy. Septic embolization to the coronary arteries is a rare complication [1]. Several management strategies exist including either percutaneous or surgical options. Aerococcus urinae (A. urinae) was initially defined as a human pathogen in 1992 and is characterized as a gram-positive, catalase-negative coccus resembling Staphylococcus. Although generally considered to harbor limited virulence, it can cause severe and fatal bloodstream infections. Aerococcus species as a cause of IE, itself is uncommon among the general population [2]. We report a 54 year-old patient with acute mitral valve (MV) IE due to A. urinae who presented with acute myocardial infarction. A 54 year-old farmer presented with persistent fever and chills despite antibiotic treatment. Initial evaluation showed ST-segment elevation in the inferior leads with elevated troponins. Echocardiography revealed severe MV regurgitation and large mobile vegetations (Fig 1A). There was evidence of severe right ventricular dysfunction and severe tricuspid valve (TV) regurgitation. CT scan of head, chest, and abdomen showed bilateral pulmonary nodules suspicious of septic emboli and splenic infarcts with no evidence of acute intracranial pathology. Clinical examination revealed phimosis with meatal stenosis. Decision was made to proceed with surgery due to the presence of heart failure and risk of embolization. Preoperative coronary angiogram showed 100% occlusion of proximal right coronary artery (RCA) (Fig 1B). The
Accepted for publication Feb 18, 2016. Address correspondence to Dr Said, Mayo Clinic, 200 1st St SW, Rochester, MN 55905; email: [email protected].
Ó 2016 by The Society of Thoracic Surgeons Published by Elsevier
left anterior descending and circumflex arteries were free of any significant stenosis. Through a median sternotomy, and aortic and bicaval cannulation, the MV was approached through a vertical transseptal approach. Large vegetations were identified on the posterior leaflet of the MV with marked thickening of the anterior leaflet (Fig 2A). There were no vegetations on the TV. The RCA was dissected in the atrioventricular groove down to the acute margin of the heart. An arteriotomy was made along the long axis of the RCA where we identified a 2-cm-long embolus (Figs 2B, 2C). The rest of the RCA was clean and free of any disease. MV replacement with 31 mm SJM Epic valve (St. Jude Medical, Inc, St. Paul, MN), TV repair with 28 mm Carbomedics annuloplasty ring (Sorin-CarboMedics, Austin, TX), and RCA embolectomy with a saphenous vein patch arterioplasty (Fig 2D) were performed. A reversed saphenous vein graft bypass to the distal RCA was added. Postoperative recovery was uneventful and patient was discharged from the hospital 6 days later. CT coronary angiogram prior to discharge showed occlusion of the proximal native RCA where embolectomy was performed, however, the saphenous vein graft to distal RCA bypass was widely patent (Fig 3). Preoperative blood cultures grew A. urinae. The vegetations on the MV and the culture from the RCA embolus were positive for A. urinae. Patient was discharged on ampicillin monotherapy for 6 weeks.
Comment Systemic embolization in IE is very common (incidence of 22% to 50%), most commonly to the central nervous system. However embolization to coronary arteries is a rare event (incidence 2.9% to 10.6%) [3]. The majority of these involve the left coronary system, probably due to the preferential flow related to aortic valve morphology [4]. Aerococcus species as a cause of IE [2] is extremely rare. Older males predominated in a recent review and several had urologic diagnoses, with the most common urologic condition being benign prostate hyperplasia. Of the reported cases of Aerococcus species infections, IE complications were common in 24 cases [5]; indeed, 21% underwent valve surgery, and 46% of the overall group died. Clearly, in the current case report that describes phimosis and urethral meatal stenosis, it is reasonable that the latter could have predisposed to at least urinary colonization with A. urinae, although a urine culture prior to an IE diagnosis was negative. Management of patients with coronary embolization in the setting of IE is controversial. Options available include catheter-based interventions such as thrombolysis, percutaneous transluminal coronary angioplasty (PTCA) with or without stent placement, and catheter aspiration or surgery. Thrombolysis is often contraindicated in these settings due to the higher risk of intracerebral hemorrhage [6]. 0003-4975/$36.00 http://dx.doi.org/10.1016/j.athoracsur.2016.02.069
e296
CASE REPORT KOTKAR ET AL RIGHT CORONARY ARTERY EMBOLISM IN ACUTE INFECTIVE ENDOCARDITIS
Ann Thorac Surg 2016;102:e295–7
Fig 1. (A) Transthoracic parasternal long-axis systolic zoomed still frame shows a large vegetation (arrow) prolapsing into the left atrium in systole. (B) Left anterior oblique cranial projection coronary angiogram showing abrupt cutoff at mid– right coronary artery level.
PTCA with stent placement may be associated with development of mycotic aneurysms, failure to achieve coronary patency and distal embolization. The use of drug eluting stents predisposes to a higher risk of reinfection as compared to bare metal stents due to their immunomodulatory properties [7]. Aspiration catheters are an attractive option; however they are rarely effective in isolation. Surgery represents an ideal option due to the ability to eradicate the infection, and management of all associated valve pathology. Surgical coronary embolectomy through a direct coronary arteriotomy is well-recognized technique [6].
Fig 2. (A) Pathological specimen of excised mitral leaflet with vegetations. (B) Operative image showing right coronary artery (RCA) opened up showing the embolus in situ. (C) Pathological specimen on the embolus. (D) Completed saphenous vein patch arterioplasty of RCA.
The indications for surgery in our case were clear; however, the timing and the management strategy for the RCA were not. Reversed saphenous venous graft bypass to the distal RCA alone was associated with a risk of leaving potentially infected material within the RCA. Septic emboli have been known to cause mycotic aneurysms in coronary arteries [8]. An infected embolus in a 100% blocked coronary artery (as in our case) represents a source of infection, which has very poor antibiotic penetration. This is further supported by the fact the coronary embolus grew A. urinae after the blood cultures had turned negative.
Ann Thorac Surg 2016;102:e295–7
CASE REPORT KOTKAR ET AL RIGHT CORONARY ARTERY EMBOLISM IN ACUTE INFECTIVE ENDOCARDITIS
e297
Is additional surgical revascularization necessary after embolectomy? This is a difficult question to answer due to the limited data in literature and the rarity of such cases. In our case, despite completely removing the RCA embolus, we felt that additional bypass with a vein graft would provide additional safety in case of reocclusion of the RCA. Our treatment plan proved to be effective as the predismissal CT showed thrombosis at the embolectomy site with widely patent bypass graft.
References
Fig 3. Postoperative computed tomography coronary angiogram showing thrombosed mid–right coronary artery (RCA) (yellow arrow) with patent saphenous venous graft to RCA (blue arrow).
Performing an embolectomy alone is also an option, as the proximal and mid RCA are easily accessible for surgical embolectomy. However there is always a possibility that the embolectomy site will develop thrombosis due to endothelial disruption. Also there is no logical method of confirming completion of embolectomy as distal showering of emboli during the procedure is possible.
1. Baek M-J, Kim HK, Yu CW, Na CW. Mitral valve surgery with surgical embolectomy for mitral valve endocarditis complicated by septic coronary embolism. Eur J Cardiothorac Surg 2008;33:116–8. 2. DeSimone DC, Tleyjeh IM, Correa de Sa DD, et al. Temporal trends in infective endocarditis epidemiology from 2007 to 2013 in Olmsted County. MN. Am Heart J 2015;170:830–6. 3. Manzano MC, Vilacosta I, San Roman JA, et al. [Acute coronary syndrome in infective endocarditis]. Rev Esp Cardiol 2007;60:24–31. 4. Prizel KR, Hutchins GM, Bulkley BH. Coronary artery embolism and myocardial infarction, a clinicopathologic study of 55 patients. Ann Intern Med 1978;88:155–61. 5. Rasmussen M. Aerococci and aerococcal infections. J Infect 2013;66:467–74. 6. Singh M, Mishra A, Kaluski E. Acute ST-elevation myocardial infarction due to septic embolism: A case report and review of management options. Cathet Cardiovasc Interv 2015;85: E166–71. 7. Patel AJ, Mehta RM, Gandhi DB, et al. Coronary aneurysm and purulent pericardial effusion: Old disease with an unusual cause. Ann Thorac Surg 2013;95:1791–3. 8. Reece IJ, Al Tareif H, Tolia J, Saeed FA. Mycotic aneurysm of the left anterior descending coronary artery after aortic endocarditis. A case report and brief review of the literature. Tex Heart Inst J 1994;21:231–5.