CORRESPONDENCE

Traumatic Aortic Rupture To the Editor: Drs. McIlduff, Foster, and Alley should be com- mended on their astute observation that the roentgenographic image of a nasogastric tube may be displaced to the right by the mediastinal hematoma produced by aortic disruption (Ann Thorac Surg 24:77, 1977). However, before this roentgenographic phenomenon can be accepted as a reliable indicator of traumatic aortic rupture, two questions must be answered. How frequently does displacement of the esophagus (nasogastric tube) occur in a series of pa- tients with traumatic aortic rupture? How frequently is esophageal (nasogastric ‘tube) displacement ob- served in patients who incur blunt thoracic trauma but do not suffer aortic rupture?

Indirect answers to these questions can be inferred from existing data. The roentgenographic finding of displacement of the nasogastric tube is probably a reflection of a previously described sign of aortic rupture-increased thickness of the right para- esophageal strip. If this assumption is correct, then this roentgenographic indication should be use- ful since increased thickness of the right para- esophageal strip was noted in 2 of 5 patients with aortic rupture but in none of 40 patients who suffered blunt thoracic trauma without aortic rupture [2]. Perhaps increased thickness of the right para- esophageal strip would have been more easily appreciated if a nasogastric tube had been in place at the time of the initial chest roentgenogram to outline the course of the esophagus.

One patient in the Saint Paul-Ramsey Hospital se- ries [13 demonstrated marked displacement of the nasogastric tube on initial chest roentgenogram (Fig- ure). As the Figure indicates, many of the other signs of traumatic aortic rupture were also present.

Roentgenographic evidence of nasogastric tube

Chest roentgenogram of a patient wi th traumatic rup- ture of the thoracic aorta demonstrates displacement to the right (arrow) of the roentgenographic image of a nasogastric tube.

displacement in a patient who has suffered blunt thoracic trauma should alert the surgeon to look for other roentgenographic signs of aortic rupture. If such displacement is found, it is helpful in diagnos- ing aortic rupture; its absence is not noteworthy.

James Sturm, M . D . 3561 Radcliff Rd Cleveland, OH 44121

References 1. Bodily KC, Perry JF, Strate RG, et al: The sal-

vageability of patients with post-traumatic rup- ture of the descending thoracic aorta in a primary trauma center. J Trauma 17:754, 1977

2. Marsh DG, Sturm JT: Traumatic aortic rupture: roentgenographic indications for angiography. Ann Thorac Surg 21:337, 1976

LV Wall Rupture To the Editor: We enjoyed the very informative article ”Intraopera- tive Posterior Left Ventricular Wall Rupture Asso- ciated with Mitral Valve Replacement” by Wolpowitz and co-workers (Ann Thorac Surg 25:551, 1978).

In our practice in cardiac surgery, we have had two episodes of wall rupture. One was fatal and was re- lated to separation of the atrioventricular sulcus fol- lowing debridement of a heavily calcified mitral an- nulus, as the authors described. The other was caused by a prong of the Hancock prosthesis per- forating the posterior wall of the ventricle. The perfo- ration occurred just as the valve was being seated. The anterior portion of the valve corresponding to the anterior leaflet of the mitral valve was seated first. Then the posterior portion of the valve was seated. At that time it was pushed through the wall of the ventricle. That this had happened was recognized because extensive bleeding occurred after the patient came off cardiopulmonary bypass. With reinstitution of bypass and visualization of the posterior wall and the ventricle, the prong was noted to have perfo- rated. This was easily repaired, and the patient sur- vived.

It is now our policy to position the prongs of a Hancock prosthesis in such a way that they do not come in contact with the ventricular muscle. I believe this will eliminate the problem. Again, we con- gratulate the authors on a timely review.

Steven I . Phillips, M.D. Robert H . Zeff, M.D. Cham Kongtahworn, M.D.

1047 5 th A v e Des Moines, IA 50314

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