Comments

A PFO can be demonstrated on TEE in 20% to 25% of adults. The PFO typically is best seen from a high esophageal view of the atrial septum, with the transducer rotated between 60 and 90 degrees. The PFO is seen at the junction of the secundum septum (covering the fossa ovalis) and the primum septum. In most patients the PFO is small and functions as a “flap valve,” with no flow across the septum when atrial pressures are low and left atrial pressure is slightly higher than right atrial pressure. With a transient elevation in right atrial pressure, for example with Valsalva maneuver, the flap valve opens and blood can flow from right to left. With chronic elevation in atrial pressure, the PFO may become stretched with a defect between the right and left atrium allowing flow, even at rest. A small PFO is typically a benign incidental finding without associated clinical symptoms or signs. However, there is an association between the presence of a PFO and cryptogenic stroke, with studies in progress testing the hypothesis that closing the PFO will decrease the risk of recurrent stroke.

Suggested reading

• 1.
  

  Asrress KN, Marciniak M, Marciniak A, Rajani R, Clapp B: Patent foramen ovale: the current state of play, Heart 101(23): 1916–1925, 2015.

  
  
• 2.
  

  Gupta SK, Shetkar SS, Ramakrishnan S, Kothari SS: Saline contrast echocardiography in the era of multimodality imaging—importance of “bubbling it right”. Echocardiography 32(11): 1707–1719, 2015.

Comments

In addition to a PFO, this patient has an atrial septal aneurysm, defined as transient bulging of the fossa ovalis region greater than 1.5 cm in the absence of chronically elevated left or right atrial pressures. The presence of an atrial septal aneurysm is associated with a higher risk of embolic stroke than a PFO alone, most likely related to the high (>90%) prevalence of fenestrations of the septum in patients with a septal aneurysm. In patients with recurrent neurologic events despite adequate medical therapy, PFO closure may be considered, either surgically or using a percutaneously inserted closure device.

Suggested reading

• 1.
  

  McGrath ER, Paikin JS, Motlagh B, et al: Transesophageal echocardiography in patients with cryptogenic ischemic stroke: a systematic review, Am Heart J 168(5):706–712, 2014.

Comments

The most common type of atrial septal defect (ASD) is a secundum ASD, with the defect located centrally in the septum typically measuring ≥1 cm diameter. Although most ASDs are diagnosed and treated in childhood, a substantial number are not recognized until young adulthood, with a few diagnosed only later in life, as in this case.

The TEE features of an atrial septal defect are the consequence of right-sided volume overload. Blood flows left to right across the atrial defect so that the right heart pumps a larger stroke volume than the left heart. The severity of shunting is measured as the pulmonary flow (Qp) to systemic flow (Qs) ratio, where 1 is normal. A Qp:Qs ratio >1.5:1 is associated with progressive right atrial and right ventricular enlargement. In addition, ventricular septal curvature is reversed with “paradoxical” septal motion. Pulmonary hypertension is unusual with a secundum ASD. TTE may demonstrate the atrial defect itself with color Doppler showing left-to-right flow. A contrast study can be performed when right heart enlargement is present and images of the atrial septum are suboptimal.

TEE provides better images of the interatrial septum and is helpful when percutaneous closure is planned, to measure the size of the defect and evaluate the rim of tissue that will anchor the device.

Suggested reading

• 1.
  

  Brickner ME, Hillis LD, Lange RA: Congenital heart disease in adults. First of two parts, N Engl J Med 342:256–263, 2000.

  
  
• 2.
  

  Brickner ME, Hillis LD, Lange RA: Congenital heart disease in adults. Second of two parts, N Engl J Med 342:334–342, 2000.

  
  
• 3.
  

  Faletra FF, Pedrazzini G, Pasotti E, et al: 3D TEE during catheter-based interventions, JACC Cardiovasc Imaging 7(3):292–308, 2014.

Comments

A primum ASD is seen in the base of the septum, adjacent to the atrioventricular valve plane and, in effect, is a partial atrioventricular canal defect. The defect is best seen in a four-chamber view, both on 2D imaging and with color Doppler. These defects are large, typically requiring surgical closure with placement of a patch. Many patients have associated abnormalities of the atrioventricular valve, most commonly a cleft anterior mitral valve leaflet. Some cleft leaflets can be repaired by approximation of the two segments, but others require replacement if the valve is deformed or if there is excessive tension when the segments are sutured together. The echocardiographer should also carefully evaluate for a ventricular septal defect (VSD) in patients with a primum ASD.

Suggested reading

• 1.
  

  Mahmood F: Perioperative transesophageal echocardiography: Current status and future direction, Heart 102:1159–1167, 2016.

  
  
• 2.
  

  Randolph GR, Hagler DJ, Connolly HM, et al: Intraoperative transesophageal echocardiography during surgery for congenital heart defects, J Thorac Cardiovasc Surg 124:1176–1182, 2002.

Comments

This case illustrates the utility of intraoperative TEE guidance during surgery for complex congenital heart disease. Recognition of subaortic obstruction due to the annuloplasty ring impinging on the narrow LV outflow tract in this patient with a history of an AV canal defect resulting in prompt correction at the same surgical procedure.

Suggested reading

• 1.
  

  De Mey N, Couture P, Denault AY, et al: Subaortic stenosis after atrioventricular septal defect repair, Anesth Analg 113:236–238, 2011.

  
  
• 2.
  

  Kutty S, Smallhorn JF: Evaluation of atrioventricular septal defects by three-dimensional echocardiography: benefits of navigating the third dimension, J Am Soc Echocardiogr 25(9): 932–944, 2012.