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Right Coronary Artery Occlusion After Tricuspid Ring Annuloplasty
CASE REPORT
Right Coronary Artery Occlusion After Tricuspid Ring Annuloplasty Jordan Goldhammer, MD,* William Clark Hargrove III, MD,† and William J. Vernick, MD‡
T
HE DETECTION OF ISCHEMIA during cardiac surgery is not an uncommon finding; however, the interpretation of signs of ischemia is challenging secondary to both the diffuse etiologies associated with ischemic insult, and the limited intraoperative ability to differentiate and localize potential injury. This case presents a rare iatrogenic coronary artery injury and illustrates the challenges associated with the diagnosis and management of perioperative ischemia after cardiac surgery.
CASE PRESENTATION
An 82-year-old male with congestive heart failure was referred for surgical management of known severe mitral regurgitation (MR). Preoperative transesophageal echocardiography (TEE) revealed severe left atrial enlargement, severe eccentric MR secondary to a flail P2-P3 scallop with annular dilation, left ventricular ejection fraction of 45%, tricuspid annular dilation with moderate central tricuspid regurgitation, and mild right ventricular dilation with preserved systolic function. Preoperative cardiac catheterization prior to surgery had identified diffuse non-critical coronary artery disease in a right dominant circulation and a 60% proximal right coronary artery stenosis. During preoperative surgical consultation, the patient expressed his desire to avoid median sternotomy, and a minimally invasive mitral and tricuspid valve repair was planned. Anesthesia was induced with propofol, fentanyl, and rocuronium. The trachea was intubated uneventfully with a 37-French left double-lumen tube, and a 9-French introducer with multi-orifice pulmonary artery catheter was placed in the right internal jugular vein. The patient was positioned supine with the right upper chest elevated via a roll placed under his right scapula. The surgical repair was initiated through a small right anterior thoracotomy incision. Arterial and venous access for cardiopulmonary bypass (CPB) were obtained by
From the *Department of Anesthesiology, Thomas Jefferson University Hospital; †Department of Cardiac Surgery, Penn-Presbyterian Medical Center; and ‡Department of Anesthesia and Crtical Care, Hospital of the University of Pennsylvania, Philadelphia, PA. Address reprint requests to Jordan Goldhammer, MD, Thomas Jefferson University Hospital, Department of Anesthesiology, 111 S. 11th Street, Gibbon Building, Suite 8280, Philadelphia, PA 19107. E-mail: [email protected] © 2015 Elsevier Inc. All rights reserved. 1053-0770/2602-0033$36.00/0 http://dx.doi.org/10.1053/j.jvca.2014.11.014 Key words: right coronary artery occlusion, mechanical occlusion, suture occlusion, perioperative ischemia, tricuspid valve annuloplasty, cardiac surgery 1606
percutaneous femoral cannulation. An additional 16-F percutaneous right internal jugular cannula ensured adequate venous drainage. A Chitwood angled aortic cross-clamp was placed through a separate chest wall puncture and anterograde cardioplegia administered via direct aortic cannulation. The mitral valve was approached through the left atrium and repaired with a triangular resection of the posterior leaflet and a ring annuloplasty (#30 Carbomedics AnnuloFlex Band). The dilated tricuspid annulus was repaired with a ring annuloplasty (#30 Carpentier Edwards Tricuspid Annuloplasty Band) (Fig 1). Prior to separation from CPB, TEE imaging was notable for moderate left ventricular dysfunction, mild right ventricular dysfunction, trace residual MR, and no tricuspid regurgitation. Ventricular pacing was initiated and inotropic support provided by infusions of epinephrine at 6 µg/min and milrinone at 0.25 µg/kg/min. Left ventricular ejection fraction improved to 50%; however, an additional important finding was new, inferobasal hypokinesis observed on TEE in conjunction with new STelevations on the 5-lead electrocardiogram (ECG). While ECG analysis was limited by the need for ventricular pacing, the STelevations appeared particularly prominent in the inferior lead. The suspected inferior ischemia initially was attributed to air entering the right coronary artery (RCA); however, following prolonged reperfusion, the wall motion abnormality did not improve, and, in fact, its size expanded. Alternative hypotheses discussed with the multidisciplinary care team were poor myocardial protection causing reversible myocardial stunning, progression of known native right coronary disease, and an iatrogenic coronary injury. Considering the uncertain etiology, the patient’s relative hemodynamic stability, and the risk of additional surgery in an octogenarian who had undergone a minimally invasive procedure, the decision was made to complete the surgery and transport the patient to the intensive care unit for further evaluation. The initial 12-lead ECG upon arrival to the intensive care unit revealed ST-elevations in leads II, III, and aVF (Fig 2). While his hemodynamic parameters remained relatively stable with unchanged inotropic support, given the confirmatory 12lead ECG findings, the patient was transferred immediately to the cardiology laboratory for diagnostic catheterization. The right femoral artery was accessed using a 6-F sheath. Diagnostic images (Fig 3) revealed a 100% occlusion of the distal right coronary artery directly abutting the tricuspid ring annuloplasty. Multiple attempts to pass a wire through the occlusion site proved unsuccessful, raising suspicion for a mechanical occlusion of the distal RCA. Following discussion with a multidisciplinary care team consisting of cardiology, anesthesiology, and cardiac surgery, the patient was transferred
Journal of Cardiothoracic and Vascular Anesthesia, Vol 29, No 6 (December), 2015: pp 1606–1609
1607
RIGHT CORONARY ARTERY OCCLUSION
Fig 1. (A) Tricuspid ring annuloplasty. (B) Anatomic section showing relationship of RCA to tricuspid annulus. PAC, pulmonary artery catheter; RCA, right coronary artery; RA, right atrium; TV, tricuspid valve. (Reprinted with permission from McAlpine.1)
back to the intensive care unit for conservative management of the distal RCA occlusion and continued postoperative care. The postoperative course was complicated by continued thirddegree heart block ultimately requiring placement of a dualchamber pacemaker and an episode of severe chest pain and atrial fibrillation on postoperative day number 8. Repeat coronary angiography performed following the onset of chest pain revealed stable coronary artery disease with persistent total occlusion of the distal RCA. The patient was discharged on postoperative day number 15 to a short-term rehabilitation facility. DISCUSSION
In this presented case of iatrogenic RCA injury during mitral and tricuspid valve repair, a new isolated inferior basal wall motion abnormality was identified on TEE soon after release of the aortic cross-clamp. While all new signs suggestive of myocardial ischemia following cardiac surgery should be investigated thoroughly, the appearance of new inferior basal wall
Fig 2.
hypokinesia presents a dilemma for the cardiac surgical care team, particularly after mitral and tricuspid valve surgery. The difficulty relates to several factors. First, ventricular pacing frequently is required following mitral and tricuspid valve surgery. Pacing of the right ventricle typically is associated with ST-segment changes and widening of the QRS. This artifact renders ECG findings less specific for ischemic insult. Second, during transgastric TEE imaging, the severity of any inferior wall motion defect may be overestimated, limiting its specificity for ischemia detection. This is because evaluation of inferior motion typically is made in relation to anterior wall motion, and, if viewed somewhat obliquely, the anterior wall may appear to contract more vigorously in relation to the inferior segment.2,3 Third, the constellation of findings observed during this case are not uncommon following cardiac surgery and may present in many patients who suffer from only self-limited inferior wall motion abnormalities. The most common etiology of self-limiting inferior wall motion and ECG changes relate to the embolism of
Twelve-lead ECG, ST-elevations in leads II, III, and aVF indicative of inferior ischemia.
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GOLDHAMMER ET AL
Fig 3. (A) Preoperative RCA angiography. Patent RCA visualized in LAO view. (B) Postoperative RCA angiography. Distal RCA occlusion directly abutting tricuspid ring anuloplasty.
retained intracardiac air. In the supine position, the right coronary artery distribution is particularly vulnerable given the right coronary ostia’s more anterior anatomic location. This syndrome often is associated with right ventricular dysfunction and should improve with continued perfusion of coronary circulation.3 Reversible stunning of the myocardium also may occur during aortic cross-clamping, producing both wall motion and ECG abnormalities with the inferior base appearing particularly vulnerable. In addition, untreated native right coronary disease, as was evident in this patient, may lead to inadequate cardioplegia penetration, resulting in further myocardial protection concerns. While not typically a reversible syndrome, progression of the
LM
PV AV
MV
native coronary lesions should be considered in the differential diagnosis as well. The persistence and expansion of inferior basal hypokinesia associated with continued diffuse ECG abnormalities well after separation from CPB did create concern for an iatrogenic coronary injury. However, the differentiation from any reversible causes as well as the identification of any potential mechanism for iatrogenic injury remained unclear, particularly in this patient with a known right dominant circulation and a pre-existing right coronary lesion presenting with an isolated inferior basal wall defect. The majority of case reports that describe iatrogenic coronary artery injury during mitral valve
Proximal RCA
TV
Distal RCA
Fig 4. (A) Anatomic section showing proximity of coronary arteries to the atrioventricular valves (B) Schematic drawing of coronary circulation. TV, tricuspid valve; MV, mitral valve; AV, aortic valve; PV, pulmonic valve; LM, left main coronary artery; LV, left ventricle; RV, right ventricle. (Reprinted with permission from McAlpine.1)
1609
RIGHT CORONARY ARTERY OCCLUSION
surgery involve the circumflex artery distribution (Fig 4), with a predilection for injury in patients with left dominant coronary circulations due to the circumflex arteries’ more posterior course along the AV groove, increasing the arteries’ exposure to the mitral annulus.4–7 While circumflex injury also has been reported in right dominant patients8–10 and some anatomic studies have questioned the importance of coronary dominance in this phenomenon,10 the lack of either lateral or posterior lateral wall motion abnormalities in the authors’ patient made circumflex injury unlikely. In addition, blood flow through the circumflex artery along the posterior annulus was confirmed using color-flow Doppler. While the authors are now well aware of reports of iatrogenic right coronary injury as a consequence of mitral valve surgery,3 their infrequent nature led this scenario not to be considered by the practitioners at the time. Iatrogenic coronary artery injury during tricuspid valve surgery rarely has been reported despite the intimate anatomic relationship of the tricuspid annulus and the RCA (Fig 4). Given the patient’s relative hemodynamic stability and without a well-defined mechanism for ischemia, the decision was made to complete the surgery and move the patient to the intensive care unit for further evaluation. For most patients undergoing minimally invasive cardiac surgery with suspected iatrogenic coronary injury, intraoperative management options are limited. Converting to sternotomy and contemplating coronary artery bypass grafting (CABG) without knowing the precise anatomic location of the lesion to correctly bypass is generally inappropriate. Even if the procedure had been performed via sternotomy, there was no clear indication to perform CABG without angiographic guidance. Similarly, returning the patient to CPB to remove any offending sutures or removing the entire annuloplasty ring without knowing the precise mechanism or location of injury would increase the operative risk without guaranteeing success, as clearly evidenced in this patient in whom the tricuspid annuloplasty ring would not have been considered the etiology of ischemia. After a brief re-evaluation period in the intensive care unit, the patient was brought immediately to the cardiac catheterization laboratory. In this patient, there were clear indications to
perform angiography; but in a more general sense, postoperative cardiac catheterization is relatively well tolerated, and it is likely better to err on the side of overtesting if a concern exists. If coronary injury is found, a return to the operating room is not necessarily indicated, and the successful use of percutaneous intervention has been well described. Unfortunately for the presented patient, his complete vessel ligation proved not to be amenable to stenting. While consideration for reoperation was made, given his advanced age, the continued need for hemodynamic support, and the distal nature of his lesion, the risks of reoperation were considered prohibitive relative to their potential benefit, and conservative management was chosen. Ultimately, the patient recovered despite a prolonged hospitalization, mostly related to management of atrial fibrillation and need for a pacemaker. The role of his inferior ischemia in precipitating atrial fibrillation as well as the subsequent need for a pacemaker is unclear, but both complications are well known to occur as a consequence of combined mitral and tricuspid procedures. There are limited evidence to suggest an increased risk of iatrogenic coronary artery injury using minimally invasive techniques, and it is unclear if the outcome would have been different had the procedure been performed via median sternotomy. While signs of inferior wall ischemia were obvious, a clear mechanism was not. Given that poor inferior myocardial protection remained a potential culprit, had the sternum been already open, it is unlikely that a CABG would have been undertaken without precise knowledge of the coronary anatomy. Intraoperative angiography may have improved his outcome, but most operating rooms are not well set up to accommodate this, and intraoperative transfer to a hybrid operating room may not always be feasible or timely. In conclusion, this case illustrates the rare complication of mechanical right coronary artery occlusion secondary to tricuspid ring annuloplasty and the challenges associated with the diagnosis and management of iatrogenic coronary artery injury. Therapy is made difficult by both the diffuse etiologies associated with perioperative ischemia, and the limited intraoperative ability to differentiate various syndromes and properly localize injury.
REFERENCES 1. McAlpine WA: Heart and coronary arteries: An anatomical atlas for clinical diagnosis, radiological investigation, and surgical treatment. New York: Springer–Verlag, 1975 2. Heinicke N, Benesch B, Kaiser T, et al: Mechanisms of regional wall motion abnormalities in contrast-enhanced dobutamine stress echocardiography. Clin Res Cardiol 95:650-656, 2006 3. Banayan J, Dhawan R, Vernick WJ, et al: CASE 3–2012. Iatrogenic circumflex artery injury during minimally invasive mitral valve surgery. J Cardiothorac Vasc Anesth 26:512-519, 2012 4. Virmani R, Chun PK, Parker J, et al: Suture obliteration of the circumflex coronary artery in three patients undergoing mitral valve operation. Role of left dominant or codominant coronary artery. J Thorac Cardiovasc Surg 84:773-778, 1982 5. Cornu E, Lacroix PH, Christides C, et al: Coronary artery damage during mitral valve replacement. J Cardiovasc Surg 36:261-264, 1995
6. Kaklikkaya I, Yeginoglu G: Damage to coronary arteries during mitral valve surgery. Heart Surg Forum 6:E138-E142, 2003 7. Morin D, Fischer AP, Sohl BE: Iatrogenic myocardial infarction. A possible complication of mitral valve surgery related to anatomical variation of the circumflex coronary artery. Thorac Cardiovasc Surg 30: 176-179, 1982 8. Grande AM, Fiore A, Massetti M, et al: Iatrogenic circumflex coronary lesion in mitral valve surgery: Case report and review of the literature. Tex Heart I J 35:179-183, 2008 9. Mulpur AK, Kotidis KN, Nair UR: Partial circumflex artery injury during mitral valve replacement: Late presentation. J Cardiovasc Surg 41:333-334, 2000 10. Pessa CJN, Gomes WJ, Catani R, et al: Anatomical relationship between the post mitral valve annulus and coronary arteries. Implications to operative treatment. Brazil J Cardiovasc Surg 19:372-377, 2004
Right Coronary Artery Occlusion After Tricuspid Ring Annuloplasty Jordan Goldhammer, MD,* William Clark Hargrove III, MD,† and William J. Vernick, MD‡
T
HE DETECTION OF ISCHEMIA during cardiac surgery is not an uncommon finding; however, the interpretation of signs of ischemia is challenging secondary to both the diffuse etiologies associated with ischemic insult, and the limited intraoperative ability to differentiate and localize potential injury. This case presents a rare iatrogenic coronary artery injury and illustrates the challenges associated with the diagnosis and management of perioperative ischemia after cardiac surgery.
CASE PRESENTATION
An 82-year-old male with congestive heart failure was referred for surgical management of known severe mitral regurgitation (MR). Preoperative transesophageal echocardiography (TEE) revealed severe left atrial enlargement, severe eccentric MR secondary to a flail P2-P3 scallop with annular dilation, left ventricular ejection fraction of 45%, tricuspid annular dilation with moderate central tricuspid regurgitation, and mild right ventricular dilation with preserved systolic function. Preoperative cardiac catheterization prior to surgery had identified diffuse non-critical coronary artery disease in a right dominant circulation and a 60% proximal right coronary artery stenosis. During preoperative surgical consultation, the patient expressed his desire to avoid median sternotomy, and a minimally invasive mitral and tricuspid valve repair was planned. Anesthesia was induced with propofol, fentanyl, and rocuronium. The trachea was intubated uneventfully with a 37-French left double-lumen tube, and a 9-French introducer with multi-orifice pulmonary artery catheter was placed in the right internal jugular vein. The patient was positioned supine with the right upper chest elevated via a roll placed under his right scapula. The surgical repair was initiated through a small right anterior thoracotomy incision. Arterial and venous access for cardiopulmonary bypass (CPB) were obtained by
From the *Department of Anesthesiology, Thomas Jefferson University Hospital; †Department of Cardiac Surgery, Penn-Presbyterian Medical Center; and ‡Department of Anesthesia and Crtical Care, Hospital of the University of Pennsylvania, Philadelphia, PA. Address reprint requests to Jordan Goldhammer, MD, Thomas Jefferson University Hospital, Department of Anesthesiology, 111 S. 11th Street, Gibbon Building, Suite 8280, Philadelphia, PA 19107. E-mail: [email protected] © 2015 Elsevier Inc. All rights reserved. 1053-0770/2602-0033$36.00/0 http://dx.doi.org/10.1053/j.jvca.2014.11.014 Key words: right coronary artery occlusion, mechanical occlusion, suture occlusion, perioperative ischemia, tricuspid valve annuloplasty, cardiac surgery 1606
percutaneous femoral cannulation. An additional 16-F percutaneous right internal jugular cannula ensured adequate venous drainage. A Chitwood angled aortic cross-clamp was placed through a separate chest wall puncture and anterograde cardioplegia administered via direct aortic cannulation. The mitral valve was approached through the left atrium and repaired with a triangular resection of the posterior leaflet and a ring annuloplasty (#30 Carbomedics AnnuloFlex Band). The dilated tricuspid annulus was repaired with a ring annuloplasty (#30 Carpentier Edwards Tricuspid Annuloplasty Band) (Fig 1). Prior to separation from CPB, TEE imaging was notable for moderate left ventricular dysfunction, mild right ventricular dysfunction, trace residual MR, and no tricuspid regurgitation. Ventricular pacing was initiated and inotropic support provided by infusions of epinephrine at 6 µg/min and milrinone at 0.25 µg/kg/min. Left ventricular ejection fraction improved to 50%; however, an additional important finding was new, inferobasal hypokinesis observed on TEE in conjunction with new STelevations on the 5-lead electrocardiogram (ECG). While ECG analysis was limited by the need for ventricular pacing, the STelevations appeared particularly prominent in the inferior lead. The suspected inferior ischemia initially was attributed to air entering the right coronary artery (RCA); however, following prolonged reperfusion, the wall motion abnormality did not improve, and, in fact, its size expanded. Alternative hypotheses discussed with the multidisciplinary care team were poor myocardial protection causing reversible myocardial stunning, progression of known native right coronary disease, and an iatrogenic coronary injury. Considering the uncertain etiology, the patient’s relative hemodynamic stability, and the risk of additional surgery in an octogenarian who had undergone a minimally invasive procedure, the decision was made to complete the surgery and transport the patient to the intensive care unit for further evaluation. The initial 12-lead ECG upon arrival to the intensive care unit revealed ST-elevations in leads II, III, and aVF (Fig 2). While his hemodynamic parameters remained relatively stable with unchanged inotropic support, given the confirmatory 12lead ECG findings, the patient was transferred immediately to the cardiology laboratory for diagnostic catheterization. The right femoral artery was accessed using a 6-F sheath. Diagnostic images (Fig 3) revealed a 100% occlusion of the distal right coronary artery directly abutting the tricuspid ring annuloplasty. Multiple attempts to pass a wire through the occlusion site proved unsuccessful, raising suspicion for a mechanical occlusion of the distal RCA. Following discussion with a multidisciplinary care team consisting of cardiology, anesthesiology, and cardiac surgery, the patient was transferred
Journal of Cardiothoracic and Vascular Anesthesia, Vol 29, No 6 (December), 2015: pp 1606–1609
1607
RIGHT CORONARY ARTERY OCCLUSION
Fig 1. (A) Tricuspid ring annuloplasty. (B) Anatomic section showing relationship of RCA to tricuspid annulus. PAC, pulmonary artery catheter; RCA, right coronary artery; RA, right atrium; TV, tricuspid valve. (Reprinted with permission from McAlpine.1)
back to the intensive care unit for conservative management of the distal RCA occlusion and continued postoperative care. The postoperative course was complicated by continued thirddegree heart block ultimately requiring placement of a dualchamber pacemaker and an episode of severe chest pain and atrial fibrillation on postoperative day number 8. Repeat coronary angiography performed following the onset of chest pain revealed stable coronary artery disease with persistent total occlusion of the distal RCA. The patient was discharged on postoperative day number 15 to a short-term rehabilitation facility. DISCUSSION
In this presented case of iatrogenic RCA injury during mitral and tricuspid valve repair, a new isolated inferior basal wall motion abnormality was identified on TEE soon after release of the aortic cross-clamp. While all new signs suggestive of myocardial ischemia following cardiac surgery should be investigated thoroughly, the appearance of new inferior basal wall
Fig 2.
hypokinesia presents a dilemma for the cardiac surgical care team, particularly after mitral and tricuspid valve surgery. The difficulty relates to several factors. First, ventricular pacing frequently is required following mitral and tricuspid valve surgery. Pacing of the right ventricle typically is associated with ST-segment changes and widening of the QRS. This artifact renders ECG findings less specific for ischemic insult. Second, during transgastric TEE imaging, the severity of any inferior wall motion defect may be overestimated, limiting its specificity for ischemia detection. This is because evaluation of inferior motion typically is made in relation to anterior wall motion, and, if viewed somewhat obliquely, the anterior wall may appear to contract more vigorously in relation to the inferior segment.2,3 Third, the constellation of findings observed during this case are not uncommon following cardiac surgery and may present in many patients who suffer from only self-limited inferior wall motion abnormalities. The most common etiology of self-limiting inferior wall motion and ECG changes relate to the embolism of
Twelve-lead ECG, ST-elevations in leads II, III, and aVF indicative of inferior ischemia.
1608
GOLDHAMMER ET AL
Fig 3. (A) Preoperative RCA angiography. Patent RCA visualized in LAO view. (B) Postoperative RCA angiography. Distal RCA occlusion directly abutting tricuspid ring anuloplasty.
retained intracardiac air. In the supine position, the right coronary artery distribution is particularly vulnerable given the right coronary ostia’s more anterior anatomic location. This syndrome often is associated with right ventricular dysfunction and should improve with continued perfusion of coronary circulation.3 Reversible stunning of the myocardium also may occur during aortic cross-clamping, producing both wall motion and ECG abnormalities with the inferior base appearing particularly vulnerable. In addition, untreated native right coronary disease, as was evident in this patient, may lead to inadequate cardioplegia penetration, resulting in further myocardial protection concerns. While not typically a reversible syndrome, progression of the
LM
PV AV
MV
native coronary lesions should be considered in the differential diagnosis as well. The persistence and expansion of inferior basal hypokinesia associated with continued diffuse ECG abnormalities well after separation from CPB did create concern for an iatrogenic coronary injury. However, the differentiation from any reversible causes as well as the identification of any potential mechanism for iatrogenic injury remained unclear, particularly in this patient with a known right dominant circulation and a pre-existing right coronary lesion presenting with an isolated inferior basal wall defect. The majority of case reports that describe iatrogenic coronary artery injury during mitral valve
Proximal RCA
TV
Distal RCA
Fig 4. (A) Anatomic section showing proximity of coronary arteries to the atrioventricular valves (B) Schematic drawing of coronary circulation. TV, tricuspid valve; MV, mitral valve; AV, aortic valve; PV, pulmonic valve; LM, left main coronary artery; LV, left ventricle; RV, right ventricle. (Reprinted with permission from McAlpine.1)
1609
RIGHT CORONARY ARTERY OCCLUSION
surgery involve the circumflex artery distribution (Fig 4), with a predilection for injury in patients with left dominant coronary circulations due to the circumflex arteries’ more posterior course along the AV groove, increasing the arteries’ exposure to the mitral annulus.4–7 While circumflex injury also has been reported in right dominant patients8–10 and some anatomic studies have questioned the importance of coronary dominance in this phenomenon,10 the lack of either lateral or posterior lateral wall motion abnormalities in the authors’ patient made circumflex injury unlikely. In addition, blood flow through the circumflex artery along the posterior annulus was confirmed using color-flow Doppler. While the authors are now well aware of reports of iatrogenic right coronary injury as a consequence of mitral valve surgery,3 their infrequent nature led this scenario not to be considered by the practitioners at the time. Iatrogenic coronary artery injury during tricuspid valve surgery rarely has been reported despite the intimate anatomic relationship of the tricuspid annulus and the RCA (Fig 4). Given the patient’s relative hemodynamic stability and without a well-defined mechanism for ischemia, the decision was made to complete the surgery and move the patient to the intensive care unit for further evaluation. For most patients undergoing minimally invasive cardiac surgery with suspected iatrogenic coronary injury, intraoperative management options are limited. Converting to sternotomy and contemplating coronary artery bypass grafting (CABG) without knowing the precise anatomic location of the lesion to correctly bypass is generally inappropriate. Even if the procedure had been performed via sternotomy, there was no clear indication to perform CABG without angiographic guidance. Similarly, returning the patient to CPB to remove any offending sutures or removing the entire annuloplasty ring without knowing the precise mechanism or location of injury would increase the operative risk without guaranteeing success, as clearly evidenced in this patient in whom the tricuspid annuloplasty ring would not have been considered the etiology of ischemia. After a brief re-evaluation period in the intensive care unit, the patient was brought immediately to the cardiac catheterization laboratory. In this patient, there were clear indications to
perform angiography; but in a more general sense, postoperative cardiac catheterization is relatively well tolerated, and it is likely better to err on the side of overtesting if a concern exists. If coronary injury is found, a return to the operating room is not necessarily indicated, and the successful use of percutaneous intervention has been well described. Unfortunately for the presented patient, his complete vessel ligation proved not to be amenable to stenting. While consideration for reoperation was made, given his advanced age, the continued need for hemodynamic support, and the distal nature of his lesion, the risks of reoperation were considered prohibitive relative to their potential benefit, and conservative management was chosen. Ultimately, the patient recovered despite a prolonged hospitalization, mostly related to management of atrial fibrillation and need for a pacemaker. The role of his inferior ischemia in precipitating atrial fibrillation as well as the subsequent need for a pacemaker is unclear, but both complications are well known to occur as a consequence of combined mitral and tricuspid procedures. There are limited evidence to suggest an increased risk of iatrogenic coronary artery injury using minimally invasive techniques, and it is unclear if the outcome would have been different had the procedure been performed via median sternotomy. While signs of inferior wall ischemia were obvious, a clear mechanism was not. Given that poor inferior myocardial protection remained a potential culprit, had the sternum been already open, it is unlikely that a CABG would have been undertaken without precise knowledge of the coronary anatomy. Intraoperative angiography may have improved his outcome, but most operating rooms are not well set up to accommodate this, and intraoperative transfer to a hybrid operating room may not always be feasible or timely. In conclusion, this case illustrates the rare complication of mechanical right coronary artery occlusion secondary to tricuspid ring annuloplasty and the challenges associated with the diagnosis and management of iatrogenic coronary artery injury. Therapy is made difficult by both the diffuse etiologies associated with perioperative ischemia, and the limited intraoperative ability to differentiate various syndromes and properly localize injury.
REFERENCES 1. McAlpine WA: Heart and coronary arteries: An anatomical atlas for clinical diagnosis, radiological investigation, and surgical treatment. New York: Springer–Verlag, 1975 2. Heinicke N, Benesch B, Kaiser T, et al: Mechanisms of regional wall motion abnormalities in contrast-enhanced dobutamine stress echocardiography. Clin Res Cardiol 95:650-656, 2006 3. Banayan J, Dhawan R, Vernick WJ, et al: CASE 3–2012. Iatrogenic circumflex artery injury during minimally invasive mitral valve surgery. J Cardiothorac Vasc Anesth 26:512-519, 2012 4. Virmani R, Chun PK, Parker J, et al: Suture obliteration of the circumflex coronary artery in three patients undergoing mitral valve operation. Role of left dominant or codominant coronary artery. J Thorac Cardiovasc Surg 84:773-778, 1982 5. Cornu E, Lacroix PH, Christides C, et al: Coronary artery damage during mitral valve replacement. J Cardiovasc Surg 36:261-264, 1995
6. Kaklikkaya I, Yeginoglu G: Damage to coronary arteries during mitral valve surgery. Heart Surg Forum 6:E138-E142, 2003 7. Morin D, Fischer AP, Sohl BE: Iatrogenic myocardial infarction. A possible complication of mitral valve surgery related to anatomical variation of the circumflex coronary artery. Thorac Cardiovasc Surg 30: 176-179, 1982 8. Grande AM, Fiore A, Massetti M, et al: Iatrogenic circumflex coronary lesion in mitral valve surgery: Case report and review of the literature. Tex Heart I J 35:179-183, 2008 9. Mulpur AK, Kotidis KN, Nair UR: Partial circumflex artery injury during mitral valve replacement: Late presentation. J Cardiovasc Surg 41:333-334, 2000 10. Pessa CJN, Gomes WJ, Catani R, et al: Anatomical relationship between the post mitral valve annulus and coronary arteries. Implications to operative treatment. Brazil J Cardiovasc Surg 19:372-377, 2004