E Echo Rounds
Multiple Aortic Root Cavities After an Aortic Valve Replacement Vivek Sivaraman, MBBS, MRCP, MD(Res), FRCA,* Jasprit Sidhu, BSc, MB ChB,* Yassir Iqbal, BSc, MBBS, MRCP, MRCS,† and Robert Andrew Smith, MBBS, FRCA, FFICM*
A
44-year-old woman was found to have a symptomatic early diastolic murmur suggestive of aortic regurgitation. Eighteen years earlier, she had an aortic valve (AV) replacement after an episode of infective endocarditis. A preoperative transthoracic echocardiogram (TTE) suggested a severe transvalvular aortic regurgitation and a well-seated Starr–Edwards valve, but the imaging windows were described as inadequate. A subsequent transesophageal echocardiogram (TEE) identified a large echo-free cavity measuring 2.5 cm × 3.3 cm in the aortic root with several membranes dividing the cavity. There was flow within these cavities, which communicated with the aortic root, and this was interpreted as a severe paraprosthetic regurgitation (pressure half time of 285 milliseconds). She was admitted for redo AV replacement. A TEE performed in the operating room revealed multiple aortic cavities in the midesophageal (ME) AV shortaxis (SAX) and long-axis (LAX) views (Fig. 1). Additionally, a jet was noted proximal to the prosthetic AV, which entered one of the cavities close to the root of the aorta with turbulent blood flow within the cavities (Video 1, Supplemental Digital Content 1, http://links.lww.com/AA/A933; Fig. 2). While the patient was on bypass, the surgeon was able to identify a small fistula in the subaortic region below the noncoronary sinus of Valsalva (Fig. 3) in the left ventricular outflow tract (LVOT). This defect was closed with pledgeted sutures and the AV replaced. A TEE examination performed immediately after weaning from cardiopulmonary bypass revealed a second jet entering the cavities from the LVOT. A modified ME AV LAX view with the probe turned to the right suggested that the second opening was close to the membranous interventricular septum inferior to the right coronary cusp (Video 2, Supplemental Digital Content 2, http://links.lww.com/AA/A934; Fig. 3). On the second run of cardiopulmonary bypass, this fistula was identified and closed and a new AV repositioned. A TEE examination immediately after bypass demonstrated no flow in the cavities, suggesting that all points of entry were closed with the
From the Departments of *Anaesthesia and †Surgery, The Heart Hospital, University College London Hospitals, London, United Kingdom. Accepted for publication May 11, 2014.
Written permission for publication of this report was obtained from the patient. Funding: None. Conflicts of Interest: See Disclosures at the end of the article. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s website (www.anesthesia-analgesia.org). Reprints will not be available from the authors. Address correspondence to Vivek Sivaraman, MBBS, MRCP, MD(Res), FRCA, Department of Anaesthesia, The Heart Hospital, London, 16-18 Westmoreland St., London W1G 8PH, United Kingdom. Address e-mail to Vivek. [email protected]. Copyright © 2014 International Anesthesia Research Society DOI: 10.1213/ANE.0000000000000375
October 2014 • Volume 119 • Number 4
cavities thrombosed (Video 3, Supplemental Digital Content 3, http://links.lww.com/AA/A935). The patient made a full recovery and was discharged with no complications. Periannular extension of AV endocarditis is not unusual. However, in our patient, this extension resulted in the formation of multiple cavities divided by thin membranes with 2 fistulas feeding the cavities from the LVOT. While the jet was interpreted as a paraprosthetic regurgitation in the original preoperative TEE, during the intraoperative TEE, the cavities were found to communicate with the LVOT only, which was confirmed on surgical inspection. Furthermore, a second jet was only identified after the first fistula was closed. It is possible that the originally identified fistula (Video 1, Supplemental Digital Content 1, http:// links.lww.com/AA/A933) may have been a low-pressure tract and closing this tract allowed the second one to manifest (Video 2, Supplemental Digital Content, http://links. lww.com/AA/A934). A similar report by Garneau et al.1 describes the presence of periannular cavities as a sequel of native valve endocarditis that are supplied by a single opening from the LVOT. The most common cause of aortic root cavities appears to be AV endocarditis. In a case series by Baumgartner et al.,2 52% of cases with AV endocarditis resulted in the formation of annular cavities. Perivalvular extension of prosthetic valve endocarditis is normally a serious complication resulting in high mortality.3 In a study of 872 patients with prosthetic valve endocarditis, 150 patients were noted to have periannular complications. Of these, 29 had fistulas that had formed between the aortic root and a cardiac chamber called aorto-cavitary fistulalization. The remaining 121 patients had nonruptured abscesses that were identified as echo-dense or echo-lucent cavities. Interestingly, the median duration to the detection of infective endocarditis and the periannular complications was 15 days. The majority of patients in this case series were managed surgically with mechanical valve replacements. The median time to surgery from the identification of a complication was 5 days, and the mortality was as high as 39%.3 This is in direct contrast to our patient who had the original valve replacement 18 years ago. The original preoperative TTE did not identify the periannular pathology, while the intraoperative TEE was able to identify the cavities. In the study by Anguera et al.,3 TTE was performed in 144 patients and periannular complications were detected in only 54%, while TEE in 140 patients increased detection to 96%. In our patient, a combination of ME AV SAX and LAX views helped identify the location of the first fistula, while a modified LAX view with the probe turned toward the right identified the second opening. Potentially, an epiaortic ultrasonographic examination of the AV and root may have aided in quicker identification of the fistulas. However, this option is dependent on accessibility, training, and experience. www.anesthesia-analgesia.org
799
E Echo Rounds
Figure 1. Left, A midesophageal aortic valve short-axis view demonstrating multiple cavities around the aortic root extending around the noncoronary and the left coronary sinus of Valsalva. Right, A midesophageal aortic valve long-axis view demonstrating a cross section of one of the cavities, extending up to the sinotubular junction. LA = left atrium; LV = left ventricle; RA = right atrium; AV = aortic valve.
Video 1. Midesophageal aortic valve long-axis view (ME AV LAX) demonstrating a jet entering the cavity in both systole and diastole. LA = left atrium; LV = left ventricle; AoR = aortic root.
Figure 2. Left, Continuous-wave Doppler in the deep transgastric long-axis view depicting the flow across the aortic valve in systole and diastole. The diastolic jet is most likely the backward flow from the cavity. Right, Continuous-wave Doppler in the midesophageal long-axis view was well aligned with the first jet entering the cavity. Flow is not consistent, with maximum velocities approaching 2 m/s.
The differential diagnosis for periannular pathologies includes sinus of Valsalva aneurysms,4 coronary artery aneurysms,5 aneurysm of membranous septum,6 aortic ring abscess with pseudoaneurysm formation,1 or aneurysms of
800 www.anesthesia-analgesia.org
anterior leaflet mitral valve.7 We have described an unusual complication of infective endocarditis of a prosthetic AV, where intraoperative TEE facilitated accurate localization of multiple fistulas into periannular cavities. E
anesthesia & analgesia
Multiple Aortic Root Cavities After an Aortic Valve Replacement
Figure 3. A view of the aortic valve from the left ventricle focusing on the left ventricular outflow tract, showing the location of the fistula openings marked with a red X, and the tract of the second fistula, shown with a red dotted line. The green dotted line shows the approximate extent of the cavities in the aortic root. RCC = right coronary cusp; LCC = left coronary cusp; NCC = noncoronary cusp; AML = anterior mitral leaflet; RV = right ventricle.
Video 2. Midesophageal aortic valve long-axis view (ME AV LAX) with probe turned to the patient’s right, obtained immediately after cardiopulmonary bypass demonstrating a second jet entering the cavity. The point of origin of the jet is not clear but seems to run close to the right ventricle. LA = left atrium; LV = left ventricle; RV = right ventricle.
Video 3. Midesophageal aortic valve short-axis view (ME AV SAX) obtained after the second run of cardiopulmonary bypass, with and without color flow Doppler. LA = left atrium; LV = left ventricle; AoR = aortic root.
October 2014 • Volume 119 • Number 4
www.anesthesia-analgesia.org
801
E Echo Rounds DISCLOSURES
Name: Vivek Sivaraman, MBBS, MRCP, MD(Res), FRCA. Contribution: This author performed the echocardiographic study and helped prepare the manuscript. Attestation: Vivek Sivaraman approved the final manuscript. Conflicts of Interest: The author has no conflicts of interest to declare. Name: Jasprit Sidhu, BSc, MB ChB. Contribution: This author helped prepare the manuscript. Attestation: Jasprit Sidhu approved the final manuscript. Conflicts of Interest: The author has no conflicts of interest to declare. Name: Yassir Iqbal, BSc, MBBS, MRCP, MRCS. Contribution: This author helped prepare the manuscript. Attestation: Yassir Iqbal approved the final manuscript. Conflicts of Interest: The author has no conflicts of interest to declare. Name: Robert Andrew Smith, MBBS, FRCA, FFICM. Contribution: This author reviewed the echocardiographic findings and helped prepare the manuscript. Attestation: Robert Andrew Smith approved the final manuscript. Conflicts of Interest: Robert Andrew Smith is a developer of HeartWorks and a paid consultant to Inventive Medical Ltd. This manuscript was handled by: Martin J. London, MD.
Clinician’s Key Teaching Points
REFERENCES 1. Garneau S, Demers P, Denault AY. Unexpected periaortic cavity during heart surgery. Anesth Analg 2007;104:75–6 2. Baumgartner FJ, Omari BO, Robertson JM, Nelson RJ, Pandya A, Pandya A, Milliken JC. Annular abscesses in surgical endocarditis: anatomic, clinical, and operative features. Ann Thorac Surg 2000;70:442–7 3. Anguera I, Miro JM, San Roman JA, de Alarcon A, Anguita M, Almirante B, Evangelista A, Cabell CH, Vilacosta I, Ripoll T, Muñoz P, Navas E, Gonzalez-Juanatey C, Sarria C, GarciaBolao I, Fariñas MC, Rufi G, Miralles F, Pare C, Fowler VG Jr, Mestres CA, de Lazzari E, Guma JR, del Río A, Corey GR; AortoCavitary Fistula in Endocarditis Working Group. Periannular complications in infective endocarditis involving prosthetic aortic valves. Am J Cardiol 2006;98:1261–8 4. Rosenberger P, Cohn LH, Fox JA, Locke A, Shernan SK. Sinus of Valsalva aneurysm obstructing the right ventricular outflow tract. Anesth Analg 2006;102:1660–1 5. Alomar-Melero E, Martin TD, Janelle GM, Peng YG. An unusual giant right coronary artery aneurysm resembles an intracardiac mass. Anesth Analg 2008;107:1161–2 6. Shah AM, Rivenes SM, Fraser CD, Miller-Hance WC. Aneurysm of the atrioventricular membranous septum appearing as a right atrial cystic mass. Anesth Analg 2007; 105:1569–71 7. Stechert MM, Pletcher JR, Tseng EE, London MJ. Echo rounds: aneurysm of the anterior mitral valve. Anesth Analg 2012;114:86–8
By Martin M. Stechert, MD, Kent H. Rehfeldt, MD, and Martin J. London, MD
• Periaortic cavity formation usually results from aortic valve or prosthesis endocarditis. These cavities may communi-
cate with cardiac chambers; when a fistula develops between a periaortic cavity and the left ventricular outflow tract, echocardiographers may incorrectly report paravalvular regurgitation. • Due to the proximity of the transducer to the area of interest, transesophageal echocardiogram (TEE) is superior to transthoracic echocardiogram for the detection of periaortic complications. The identification of cavities or small fistula tracts requires a systematic examination approach, often beginning with the midesophageal aortic valve shortaxis or long-axis views. Small, stepwise increases of the multiplane transducer angle, along with the use of color Doppler, are used to identify all sources of flow into periaortic cavities. • In this case of redo aortic valve replacement with history of aortic valve endocarditis, TEE revealed multiple, septated aortic root cavities with prominent diastolic flow from a cavity into the left ventricular outflow tract, mimicking paravalvular aortic regurgitation. After aortic prosthesis replacement and fistula repair, a second fistulous communication was identified by TEE and repaired. • Besides periaortic cavity and fistula formation, the differential diagnosis of cystic periannular structures includes sinus of Valsalva aneurysm, coronary artery aneurysm, aortic root abscess or pseudoaneurysm formation, and aneurysm of the membranous ventricular septum. Along with the clinical history, a detailed TEE examination that carefully identifies points of communication (if any) and timing of blood flow can assist in correctly characterizing the pathologic structure.
802 www.anesthesia-analgesia.org
anesthesia & analgesia
Multiple Aortic Root Cavities After an Aortic Valve Replacement Vivek Sivaraman, MBBS, MRCP, MD(Res), FRCA,* Jasprit Sidhu, BSc, MB ChB,* Yassir Iqbal, BSc, MBBS, MRCP, MRCS,† and Robert Andrew Smith, MBBS, FRCA, FFICM*
A
44-year-old woman was found to have a symptomatic early diastolic murmur suggestive of aortic regurgitation. Eighteen years earlier, she had an aortic valve (AV) replacement after an episode of infective endocarditis. A preoperative transthoracic echocardiogram (TTE) suggested a severe transvalvular aortic regurgitation and a well-seated Starr–Edwards valve, but the imaging windows were described as inadequate. A subsequent transesophageal echocardiogram (TEE) identified a large echo-free cavity measuring 2.5 cm × 3.3 cm in the aortic root with several membranes dividing the cavity. There was flow within these cavities, which communicated with the aortic root, and this was interpreted as a severe paraprosthetic regurgitation (pressure half time of 285 milliseconds). She was admitted for redo AV replacement. A TEE performed in the operating room revealed multiple aortic cavities in the midesophageal (ME) AV shortaxis (SAX) and long-axis (LAX) views (Fig. 1). Additionally, a jet was noted proximal to the prosthetic AV, which entered one of the cavities close to the root of the aorta with turbulent blood flow within the cavities (Video 1, Supplemental Digital Content 1, http://links.lww.com/AA/A933; Fig. 2). While the patient was on bypass, the surgeon was able to identify a small fistula in the subaortic region below the noncoronary sinus of Valsalva (Fig. 3) in the left ventricular outflow tract (LVOT). This defect was closed with pledgeted sutures and the AV replaced. A TEE examination performed immediately after weaning from cardiopulmonary bypass revealed a second jet entering the cavities from the LVOT. A modified ME AV LAX view with the probe turned to the right suggested that the second opening was close to the membranous interventricular septum inferior to the right coronary cusp (Video 2, Supplemental Digital Content 2, http://links.lww.com/AA/A934; Fig. 3). On the second run of cardiopulmonary bypass, this fistula was identified and closed and a new AV repositioned. A TEE examination immediately after bypass demonstrated no flow in the cavities, suggesting that all points of entry were closed with the
From the Departments of *Anaesthesia and †Surgery, The Heart Hospital, University College London Hospitals, London, United Kingdom. Accepted for publication May 11, 2014.
Written permission for publication of this report was obtained from the patient. Funding: None. Conflicts of Interest: See Disclosures at the end of the article. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s website (www.anesthesia-analgesia.org). Reprints will not be available from the authors. Address correspondence to Vivek Sivaraman, MBBS, MRCP, MD(Res), FRCA, Department of Anaesthesia, The Heart Hospital, London, 16-18 Westmoreland St., London W1G 8PH, United Kingdom. Address e-mail to Vivek. [email protected]. Copyright © 2014 International Anesthesia Research Society DOI: 10.1213/ANE.0000000000000375
October 2014 • Volume 119 • Number 4
cavities thrombosed (Video 3, Supplemental Digital Content 3, http://links.lww.com/AA/A935). The patient made a full recovery and was discharged with no complications. Periannular extension of AV endocarditis is not unusual. However, in our patient, this extension resulted in the formation of multiple cavities divided by thin membranes with 2 fistulas feeding the cavities from the LVOT. While the jet was interpreted as a paraprosthetic regurgitation in the original preoperative TEE, during the intraoperative TEE, the cavities were found to communicate with the LVOT only, which was confirmed on surgical inspection. Furthermore, a second jet was only identified after the first fistula was closed. It is possible that the originally identified fistula (Video 1, Supplemental Digital Content 1, http:// links.lww.com/AA/A933) may have been a low-pressure tract and closing this tract allowed the second one to manifest (Video 2, Supplemental Digital Content, http://links. lww.com/AA/A934). A similar report by Garneau et al.1 describes the presence of periannular cavities as a sequel of native valve endocarditis that are supplied by a single opening from the LVOT. The most common cause of aortic root cavities appears to be AV endocarditis. In a case series by Baumgartner et al.,2 52% of cases with AV endocarditis resulted in the formation of annular cavities. Perivalvular extension of prosthetic valve endocarditis is normally a serious complication resulting in high mortality.3 In a study of 872 patients with prosthetic valve endocarditis, 150 patients were noted to have periannular complications. Of these, 29 had fistulas that had formed between the aortic root and a cardiac chamber called aorto-cavitary fistulalization. The remaining 121 patients had nonruptured abscesses that were identified as echo-dense or echo-lucent cavities. Interestingly, the median duration to the detection of infective endocarditis and the periannular complications was 15 days. The majority of patients in this case series were managed surgically with mechanical valve replacements. The median time to surgery from the identification of a complication was 5 days, and the mortality was as high as 39%.3 This is in direct contrast to our patient who had the original valve replacement 18 years ago. The original preoperative TTE did not identify the periannular pathology, while the intraoperative TEE was able to identify the cavities. In the study by Anguera et al.,3 TTE was performed in 144 patients and periannular complications were detected in only 54%, while TEE in 140 patients increased detection to 96%. In our patient, a combination of ME AV SAX and LAX views helped identify the location of the first fistula, while a modified LAX view with the probe turned toward the right identified the second opening. Potentially, an epiaortic ultrasonographic examination of the AV and root may have aided in quicker identification of the fistulas. However, this option is dependent on accessibility, training, and experience. www.anesthesia-analgesia.org
799
E Echo Rounds
Figure 1. Left, A midesophageal aortic valve short-axis view demonstrating multiple cavities around the aortic root extending around the noncoronary and the left coronary sinus of Valsalva. Right, A midesophageal aortic valve long-axis view demonstrating a cross section of one of the cavities, extending up to the sinotubular junction. LA = left atrium; LV = left ventricle; RA = right atrium; AV = aortic valve.
Video 1. Midesophageal aortic valve long-axis view (ME AV LAX) demonstrating a jet entering the cavity in both systole and diastole. LA = left atrium; LV = left ventricle; AoR = aortic root.
Figure 2. Left, Continuous-wave Doppler in the deep transgastric long-axis view depicting the flow across the aortic valve in systole and diastole. The diastolic jet is most likely the backward flow from the cavity. Right, Continuous-wave Doppler in the midesophageal long-axis view was well aligned with the first jet entering the cavity. Flow is not consistent, with maximum velocities approaching 2 m/s.
The differential diagnosis for periannular pathologies includes sinus of Valsalva aneurysms,4 coronary artery aneurysms,5 aneurysm of membranous septum,6 aortic ring abscess with pseudoaneurysm formation,1 or aneurysms of
800 www.anesthesia-analgesia.org
anterior leaflet mitral valve.7 We have described an unusual complication of infective endocarditis of a prosthetic AV, where intraoperative TEE facilitated accurate localization of multiple fistulas into periannular cavities. E
anesthesia & analgesia
Multiple Aortic Root Cavities After an Aortic Valve Replacement
Figure 3. A view of the aortic valve from the left ventricle focusing on the left ventricular outflow tract, showing the location of the fistula openings marked with a red X, and the tract of the second fistula, shown with a red dotted line. The green dotted line shows the approximate extent of the cavities in the aortic root. RCC = right coronary cusp; LCC = left coronary cusp; NCC = noncoronary cusp; AML = anterior mitral leaflet; RV = right ventricle.
Video 2. Midesophageal aortic valve long-axis view (ME AV LAX) with probe turned to the patient’s right, obtained immediately after cardiopulmonary bypass demonstrating a second jet entering the cavity. The point of origin of the jet is not clear but seems to run close to the right ventricle. LA = left atrium; LV = left ventricle; RV = right ventricle.
Video 3. Midesophageal aortic valve short-axis view (ME AV SAX) obtained after the second run of cardiopulmonary bypass, with and without color flow Doppler. LA = left atrium; LV = left ventricle; AoR = aortic root.
October 2014 • Volume 119 • Number 4
www.anesthesia-analgesia.org
801
E Echo Rounds DISCLOSURES
Name: Vivek Sivaraman, MBBS, MRCP, MD(Res), FRCA. Contribution: This author performed the echocardiographic study and helped prepare the manuscript. Attestation: Vivek Sivaraman approved the final manuscript. Conflicts of Interest: The author has no conflicts of interest to declare. Name: Jasprit Sidhu, BSc, MB ChB. Contribution: This author helped prepare the manuscript. Attestation: Jasprit Sidhu approved the final manuscript. Conflicts of Interest: The author has no conflicts of interest to declare. Name: Yassir Iqbal, BSc, MBBS, MRCP, MRCS. Contribution: This author helped prepare the manuscript. Attestation: Yassir Iqbal approved the final manuscript. Conflicts of Interest: The author has no conflicts of interest to declare. Name: Robert Andrew Smith, MBBS, FRCA, FFICM. Contribution: This author reviewed the echocardiographic findings and helped prepare the manuscript. Attestation: Robert Andrew Smith approved the final manuscript. Conflicts of Interest: Robert Andrew Smith is a developer of HeartWorks and a paid consultant to Inventive Medical Ltd. This manuscript was handled by: Martin J. London, MD.
Clinician’s Key Teaching Points
REFERENCES 1. Garneau S, Demers P, Denault AY. Unexpected periaortic cavity during heart surgery. Anesth Analg 2007;104:75–6 2. Baumgartner FJ, Omari BO, Robertson JM, Nelson RJ, Pandya A, Pandya A, Milliken JC. Annular abscesses in surgical endocarditis: anatomic, clinical, and operative features. Ann Thorac Surg 2000;70:442–7 3. Anguera I, Miro JM, San Roman JA, de Alarcon A, Anguita M, Almirante B, Evangelista A, Cabell CH, Vilacosta I, Ripoll T, Muñoz P, Navas E, Gonzalez-Juanatey C, Sarria C, GarciaBolao I, Fariñas MC, Rufi G, Miralles F, Pare C, Fowler VG Jr, Mestres CA, de Lazzari E, Guma JR, del Río A, Corey GR; AortoCavitary Fistula in Endocarditis Working Group. Periannular complications in infective endocarditis involving prosthetic aortic valves. Am J Cardiol 2006;98:1261–8 4. Rosenberger P, Cohn LH, Fox JA, Locke A, Shernan SK. Sinus of Valsalva aneurysm obstructing the right ventricular outflow tract. Anesth Analg 2006;102:1660–1 5. Alomar-Melero E, Martin TD, Janelle GM, Peng YG. An unusual giant right coronary artery aneurysm resembles an intracardiac mass. Anesth Analg 2008;107:1161–2 6. Shah AM, Rivenes SM, Fraser CD, Miller-Hance WC. Aneurysm of the atrioventricular membranous septum appearing as a right atrial cystic mass. Anesth Analg 2007; 105:1569–71 7. Stechert MM, Pletcher JR, Tseng EE, London MJ. Echo rounds: aneurysm of the anterior mitral valve. Anesth Analg 2012;114:86–8
By Martin M. Stechert, MD, Kent H. Rehfeldt, MD, and Martin J. London, MD
• Periaortic cavity formation usually results from aortic valve or prosthesis endocarditis. These cavities may communi-
cate with cardiac chambers; when a fistula develops between a periaortic cavity and the left ventricular outflow tract, echocardiographers may incorrectly report paravalvular regurgitation. • Due to the proximity of the transducer to the area of interest, transesophageal echocardiogram (TEE) is superior to transthoracic echocardiogram for the detection of periaortic complications. The identification of cavities or small fistula tracts requires a systematic examination approach, often beginning with the midesophageal aortic valve shortaxis or long-axis views. Small, stepwise increases of the multiplane transducer angle, along with the use of color Doppler, are used to identify all sources of flow into periaortic cavities. • In this case of redo aortic valve replacement with history of aortic valve endocarditis, TEE revealed multiple, septated aortic root cavities with prominent diastolic flow from a cavity into the left ventricular outflow tract, mimicking paravalvular aortic regurgitation. After aortic prosthesis replacement and fistula repair, a second fistulous communication was identified by TEE and repaired. • Besides periaortic cavity and fistula formation, the differential diagnosis of cystic periannular structures includes sinus of Valsalva aneurysm, coronary artery aneurysm, aortic root abscess or pseudoaneurysm formation, and aneurysm of the membranous ventricular septum. Along with the clinical history, a detailed TEE examination that carefully identifies points of communication (if any) and timing of blood flow can assist in correctly characterizing the pathologic structure.
802 www.anesthesia-analgesia.org
anesthesia & analgesia
