Skip Navigation

European Journal of Echocardiography 2004 5(6):449-452; doi:10.1016/j.euje.2004.04.004
© 2004 by European Society of Cardiology
This Article
Right arrow Abstract Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Daniëls, C.
Right arrow Articles by Van Camp, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Daniëls, C.
Right arrow Articles by Van Camp, G.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Copyright © 2004, The European Society of Cardiology

Second harmonic transthoracic echocardiography: the new reference screening method for the detection of patent foramen ovale

Cathy Daniëlsa,*, Caroline Weytjensa, Bernard Cosynsa, Danny Schoorsa, Johan De Sutterb, Bernard Paelinckc, Luc Muyldermansd and Guy Van Campa

aDepartment of Cardiology, AZ VUB, Laarbeeklaan 101, 1090 Brussels, Belgium
bDepartment of Cardiology, UZ Gent, Belgium
cDepartment of Cardiology, UZ Antwerpen, Belgium
dDepartment of Cardiology, AZ Sint Jan, Brugge, Belgium

Received 15 January 2004; received in revised form 15 April 2004; accepted after revision 20 April 2004.

* Corresponding author. Tel.: +32-2477-6388; fax: +32-2453-2294. cdaniels{at}az.vub.ac.be


   Abstract
Top
 Abstract
1. Introduction
 2. Methods
 3. Results
 4. Discussion
 References
 
Aim: Transesophageal echocardiography (TEE) is still considered as the reference method for the non-invasive detection of right-to-left shunts. Echocardiographic laboratories are spending most of their time performing TEE studies to exclude a thromboembolic cardiac disease. In a considerable proportion of these patients the question can be simplified to exclude a PFO. Replacing these TEE studies by TTE would result in a considerable gain in time and money.

We evaluated the value of transthoracic echocardiography with second harmonic imaging (TTE) (SH) and peripheral intravenous agitated saline solutions in the detection of patent foramen ovale (PFO) in a large cohort of patients.

Methods: In 256 consecutive patients, TEE and TTE (SH) with the consecutive administration of three intravenous contrast injections of agitated saline injections before the release phase of the Valsalva manoeuvre were performed. Semi-quantification and timing of contrast passage were assessed during both imaging modalities. A shunt was present if at least one imaging modality showed microbubbles appearing in the left atrium. PFO was defined when these bubbles appeared early and arteriovenous pulmonary malformations were suspected if bubbles appeared late after the opacification of the right atrium. Shunts were considered important when >20 bubbles were present in one frame in the left atrium or left ventricle.

Results: From the 256 patients, 60 presented a passage of contrast from the right to the left atrium in at least one imaging modality. PFO was detected by TEE in 53 patients and by TTE in 55 patients (sensitivity: 90.5% and specificity: 96.5% if TEE is accepted as the golden standard) (p>0.05). Considering only the important shunts TEE detected 39 important shunts and TTE 46 important shunts (sensitivity: 89.7% and specificity: 94.6%) (p>0.05).

AV pulmonary malformations were detected by TEE in 7 patients and by TTE in 10 patients (sensitivity: 85.7% and specificity: 98.3%) (p>0.05).

Conclusions: In this large cohort of patients TTE (SH) is as accurate as TEE for the detection of PFO and late right-to-left shunts. If the only purpose of TEE is the detection of PFO such as in young cryptogenic stroke patients and in divers, TEE can be replaced by TTE (SH).

Keywords: Detection of patent foramen ovale; Diagnosis of PFO (patent foramen ovale) with transthoracic versus transesophageal echocardiography


   1. Introduction
Top
 Abstract
 1. Introduction
2. Methods
 3. Results
 4. Discussion
 References
 
Transesophageal echocardiography (TEE) combined with contrast administration is considered as the method of choice in the diagnosis of patent foramen ovale (PFO) and pulmonary arteriovenous malformations.1

Because TEE studies are very time-consuming and considered as semi-invasive by the patient, we searched for a much easier, cheaper and less invasive technique to detect a PFO. Second harmonic imaging compared to fundamental mode imaging results in a much better image quality and a better visualisation of first and second generation contrast agents as well as free gas microbubbles.2 This is the reason why we assumed that transthoracic echocardiography with second harmonic imaging (TTE SH) in combination with the injection of an agitated saline solution can detect a right-to-left shunt as accurate as TEE.


   2. Methods
Top
 Abstract
 1. Introduction
 2. Methods
3. Results
 4. Discussion
 References
 
Four different centers included 256 consecutive patients (153 males, 103 females with a mean age of 63±14) referred to the echolaboratory for TEE. Motivation for TEE was stroke (n = 181, 71%), endocarditis (n = 36, 14%), valvular heart disease (n = 13, 5%), others (n = 26, 10%). Echocardiographic studies were performed with Toshiba Powervision 8000, VIVID 7, HP sonos 5500 with modalities for second harmonic imaging.

In all patients the study began with TTE. Three contrast injections were performed at low dynamic range and relative high gain settings to visualise even the most discrete contrast passage. Before contrast injections were performed attention was given to the presence of spontaneous and "snowstorm" contrast.3 The contrast injections of an agitated 10 ml physiologic saline solution were rapidly administrated through a right antecubital vein using an 18-gauge venous canula. Each injection was administrated just before the release phase of a Valsalva manoeuvre.4

The presence of an atrial septal defect or a patent foramen ovale was defined as the passage of contrast in the left cavities within the first four cardiac cycles after opacification of the right atrium. When contrast was seen in the left cavities after more than four cardiac cycles, it was considered as a passage of contrast through pulmonary arteriovenous malformation. Right-to-left shunts were considered as important when more than 20 microbubbles could be visualised during one frame. When there were less than 20 microbubbles the shunt was considered small.5,6

All studies were analysed on two different videotapes. TTE SH and TEE images were read separately and in a random order to avoid bias. Two independent readers estimated the contrast images and if there was no agreement a third reader was asked to achieve a consensus. Statistical analysis for comparing differences in severity and timing of contrast was performed with a {chi}2 test.


   3. Results
Top
 Abstract
 1. Introduction
 2. Methods
 3. Results
4. Discussion
 References
 
From the 256 patients, 60 patients presented a passage of contrast from the right to the left atrium in at least one imaging modality (Table 1). PFO was detected by TEE in 53 patients and by TTE in 55 patients (sensitivity: 90.5% and specificity: 96.5% if TEE is accepted as the golden standard) (p>0.05).


View this table:
[in this window]
[in a new window]

  		Table 1 Early contrast passage: TTE SH versus TEE

 
Important and early shunting was more often diagnosed by TTE SH than by TEE: 46 (18%) versus 39 (15%) (sensitivity: 89.7% and specificity: 94.6%) (p>0.05). Of the 46 important shunts seen on TTE SH, 5 were not visible on TEE, 6 shunts were diagnosed as small and 35 shunts were also important on TEE (Table 1). This gives a positive predictive value of 76% (Fig. 1). On the other hand, of the 39 important shunts detected with TEE, there were 4 shunts diagnosed as small on TTE SH and not one was missed with TTE SH. This gives a high negative predictive value of TTE SH for important shunting (98%).


Figure 1
View larger version (21K):
[in this window]
[in a new window]
[Download PowerPoint slide]
  		Figure 1 Sensitivity, specificity, positive predictive value and negative predictive value of TTE SH versus TEE for the detection of early contrast passage (small and important shunts) and important early contrast passage. (PPV = positive predictive value, NPV = negative predictive value).

 
Small and early shunting was more often diagnosed by TEE than by TTE: 14 (0.5%) versus 9 (0.3%). Of the 14 small shunts on TEE, 5 were not seen with TTE SH. Of the 9 small shunts visualised on TTE SH 2 small shunts were missed by TEE.

Late shunting was detected by TEE in 7 patients and by TTE in 10 patients (sensitivity: 85.7% and specificity: 98.3%) (p>0.05). Six late shunts were diagnosed with both studies. One shunt was seen on TEE and missed by TTE while four shunts detected with TTE were missed with TEE.


   4. Discussion
Top
 Abstract
 1. Introduction
 2. Methods
 3. Results
 4. Discussion
References
 
This multicenter study with a population of more than 250 patients demonstrates that TTE SH in combination with an agitated saline injection has a high sensitivity (90.5%) and specificity (96.5%) taking TEE as the golden standard for the detection of right-to-left shunts.

In our study the negative predictive value for detecting early and important contrast passage with TTE SH is very high (98%). If we cannot detect a shunt on TTE there will be also no important shunt on TEE. As already shown in previous studies, small shunts are not of clinical importance.6,7 Because there are no false negatives for the detection of large PFO, TTE SH can be seen as a good screening technique for detecting PFO.

The positive predictive value is less high (still considering TEE as the golden standard), because five important shunts detected on TTE SH were not visible on TEE. This can be explained by the difficulty of performing a good Valsalva manoeuvre in the presence of an endoscope during TEE. Previous studies have already demonstrated that TEE can miss the diagnosis of right-to-left shunts. Both transcranial Doppler and color Doppler TEE studies showed in some patients the presence of a PFO by these alternative techniques although contrast TEE was negative.8

If the only indication for TEE is the detection of PFO such as in young cryptogenic stroke patients without underlying heart disease and a minimal risk for cardio-embolic sources and in healthy divers with decompression sickness, TEE can be replaced by a much cheaper, more rapid and less invasive TTE SH approach. However, TEE will still be necessary in those patients with a high risk for trombo-emboligenic sources and in all patients without an available acoustic window by TTE SH.


   References
Top
 Abstract
 1. Introduction
 2. Methods
 3. Results
 4. Discussion
 References
 

  1. Pearson A.C., Labovitz A.J., Tatineni S., Gomez C.R. Superiority of transesophageal echocardiography in detecting cardiac sources of embolism in patients with cerebral ischemia of uncertain etiology. J Am Coll Cardiol (1991) 17:66–72.[Abstract]
  2. Van Camp G., Franken P., Melis P., Cosyns B., Schoors D., Vanoverschelde J.L., et al. Comparison of transthoracic echocardiography with second harmonic imaging with transesophageal echocardiography in the detection of right to left shunts. Am J Cardiol (2000) 86:1284–1287.[CrossRef][Web of Science][Medline]
  3. Van Camp G., Cosyns B., Vandenbossche J.L. Non-smoke spontaneous contrast in the left atrium intensified by respiratory manoeuvres: a new transoesophageal echocardiographic observation. Br Heart J (1994) 72:446–451.[Abstract/Free Full Text]
  4. Pfleger S., Konstantin Haase K., Stark S., Latsch A., Simonis B., Scherhag A., et al. Haemodynamic quantification of different provocation manoeuvres by simultaneous measurement of right and left atrial pressure: implications for the echocardiographic detection of persistent foramen ovale. Eur J Echocardiogr (2001) 2:88–93.[Abstract/Free Full Text]
  5. Webster M.W., Chancelor A.M., Smith H.J., Swift D.L., Sharp D.N., Bass N.M. Patent foramen ovale in young stroke patients. Lancet (1988) 2:11–12.[Web of Science][Medline]
  6. Van Camp G., Schulze D., Cosyns B., Vandenbossche J.L. Relation between patent foramen ovale and stroke. Am J Cardiol (1993) 71:596–598.[CrossRef][Web of Science][Medline]
  7. Vandenbogaerde J., De Bleeker J., Decoo D., François K., Cambier B., Bergen J.M., et al. Tansesophageal echo-Doppler in patients suspected of a cardiac source of peripheral emboli. Eur Heart J (1993) 13:88–94.[Web of Science]
  8. Devuyst G., Despland P.A., Bogousslavsky J., Jeanrenaud X. Complementarity of contrast transcranial Doppler and contrast transesophageal echocardiography for the detection of patent foramen ovale in stroke patients. Eur Neurol (1997) 38:21–25.[Web of Science][Medline]

Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 StrokeHome page
M.-R. Clergeau, M. Hamon, R. Morello, E. Saloux, F. Viader, and M. Hamon
Silent Cerebral Infarcts in Patients With Pulmonary Embolism and a Patent Foramen Ovale: A Prospective Diffusion-Weighted MRI Study
Stroke, December 1, 2009; 40(12): 3758 - 3762.
[Abstract] [Full Text] [PDF]

Home page
 Eur J EchocardiogrHome page
S. Maffe, P. Dellavesa, F. Zenone, A. M. Paino, P. Paffoni, A. Perucca, D. Kozel, F. Signorotti, M. Bielli, U. Parravicini, et al.
Transthoracic second harmonic two- and three-dimensional echocardiography for detection of patent foramen ovale
Eur J Echocardiogr, November 12, 2009; (2009) jep165v1.
[Abstract] [Full Text] [PDF]

Home page
 ChestHome page
M. W. F. van Gent, M. C. Post, R. J. Snijder, M. J. Swaans, H. W. M. Plokker, C. J. J. Westermann, T. T. Overtoom, and J. J. Mager
Grading of Pulmonary Right-to-Left Shunt With Transthoracic Contrast Echocardiography: Does It Predict the Indication for Embolotherapy?
Chest, May 1, 2009; 135(5): 1288 - 1292.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
M. C. Johansson, M. Dellborg, and P. Eriksson
Letter by Johansson et al Regarding Article, "Migraine Intervention With STARFlex Technology (MIST) Trial"
Circulation, February 10, 2009; 119(5): e193 - e193.
[Full Text] [PDF]

Home page
 StrokeHome page
R. P. Ward, G. Lammertin, D. E. Virnich, T. S. Polonsky, and R. M. Lang
Use of Carotid Intima-Media Thickness to Identify Patients With Ischemic Stroke and Transient Ischemic Attack With Low Yield of Cardiovascular Sources of Embolus on Transesophageal Echocardiography
Stroke, November 1, 2008; 39(11): 2969 - 2974.
[Abstract] [Full Text] [PDF]

Home page
 Br J AnaesthHome page
B. M. P. Rademaker, F. A. Groenman, P. A. van der Wouw, and E. A. Bakkum
Paradoxical gas embolism by transpulmonary passage of venous emboli during hysteroscopic surgery: a case report and discussion
Br. J. Anaesth., August 1, 2008; 101(2): 230 - 233.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
A. Dowson, M. J. Mullen, R. Peatfield, K. Muir, A. A. Khan, C. Wells, S. L. Lipscombe, T. Rees, J. V. De Giovanni, W. L. Morrison, et al.
Migraine Intervention With STARFlex Technology (MIST) Trial: A Prospective, Multicenter, Double-Blind, Sham-Controlled Trial to Evaluate the Effectiveness of Patent Foramen Ovale Closure With STARFlex Septal Repair Implant to Resolve Refractory Migraine Headache
Circulation, March 18, 2008; 117(11): 1397 - 1404.
[Abstract] [Full Text] [PDF]

Home page
 Eur J EchocardiogrHome page
O. I.I. Soliman, M. L. Geleijnse, F. J. Meijboom, A. Nemes, O. Kamp, P. Nihoyannopoulos, N. Masani, S. B. Feinstein, and F. J. Ten Cate
The use of contrast echocardiography for the detection of cardiac shunts
Eur J Echocardiogr, June 1, 2007; 8(3): s2 - s12.
[Abstract] [Full Text] [PDF]

Home page
 Eur J EchocardiogrHome page
G. Souteyrand, P. Motreff, J.-R. Lusson, R. Rodriguez, E. Geoffroy, C. Dauphin, J.-Y. Boire, D. Lamaison, and J. Cassagnes
Comparison of transthoracic echocardiography using second harmonic imaging, transcranial Doppler and transesophageal echocardiography for the detection of patent foramen ovale in stroke patients
Eur J Echocardiogr, March 1, 2006; 7(2): 147 - 154.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Daniëls, C.
Right arrow Articles by Van Camp, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Daniëls, C.
Right arrow Articles by Van Camp, G.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?