Formosan Journal of Surgery

CASE REPORT
Year
: 2017  |  Volume : 50  |  Issue : 5  |  Page : 181--182

Direct intraoperative measurement of residual pressure gradient after resection of discrete subaortic stenosis


Jiunn-Miin Lin, Shye-Jao Wu 
 Department of Surgery, Division of Cardiovascular Surgery, MacKay Memorial Hospital, Taipei, Taiwan

Correspondence Address:
Shye-Jao Wu
No. 92, Sec 2, Chung-Shan N Road, Taipei 104
Taiwan

Abstract

Transesophageal echocardiography (TEE) plays an important role for congenital cardiac surgery, such as measurement of residual shunt, residual regurgitation, residual pressure gradient (PG), and so on. For discrete subaortic stenosis, it could be a simple and effective option to check residual PG by direct intraoperative periaortic retrograde left ventricular catheterization if infantile TEE is not available.



How to cite this article:
Lin JM, Wu SJ. Direct intraoperative measurement of residual pressure gradient after resection of discrete subaortic stenosis.Formos J Surg 2017;50:181-182


How to cite this URL:
Lin JM, Wu SJ. Direct intraoperative measurement of residual pressure gradient after resection of discrete subaortic stenosis. Formos J Surg [serial online] 2017 [cited 2022 Jun 29 ];50:181-182
Available from: https://www.e-fjs.org/text.asp?2017/50/5/181/216237


Full Text



 Introduction



Transesophageal echocardiography (TEE) plays an important role for congenital cardiac surgery,[1],[2] such as measurement of residual shunt, residual regurgitation, residual pressure gradient (PG), and so on. However, infantile TEE is not the facility always available. Therefore, a simple and accurate method for checking the residual PG was designed to circumvent the problem.

 Case Report



A 1-year-5-month-old boy (body height 83 cm, body weight 11.3 kg) was a case of subaortic stenosis presenting with Grade IV/VI systolic murmur. At the age of 4 months, transthoracic echocardiography showed a subaortic ridge at left ventricular outflow tract (LVOT) with PG of 30 mmHg. When he was 1 year old, the PG increased to 52 mmHg. Cardiac catheterization showed subaortic stenosis [Figure 1] and revealed left ventricular pressure 187/11 mmHg, ascending aortic pressure 120/76 mmHg, pulmonary arterial pressure 22/9 mmHg, and the pullback PG across LVOT was 73 mmHg. Then, cardiac surgery was recommended.{Figure 1}

Under ascending aortic and bicaval cannulation with moderate hypothermic blood cardioplegic arrest, transverse aortotomy was done. Aortic valve was tricuspid and thin. Besides, one fibrotic ring below aortic valve causing LVOT obstruction was found. The subaortic ridge with some myocardium of LVOT was resected to release the LVOT obstruction. Due to no TEE available at that time at our hospital, a Fr. 4.0 catheter (Arrow, Teleflex, USA) was placed from ascending aorta through aortic valve into the left ventricle, and then the aortotomy was closed. After cardiopulmonary bypass was weaned off, the pressure of ascending aorta measured through the root vent needle and that of the left ventricle through that catheter were checked simultaneously [Figure 2]. The residual PG of 10 mmHg (pressure of ascending aorta 80/41 mmHg, pressure of left ventricle 90/12 mmHg) was recorded. During the whole procedure, the aortic cross-clamping time was 55 min and total cardiopulmonary bypass time was 101 min. After data recording, the catheter in left ventricle was removed, and the punctured hole by the catheter in the ascending aorta was secured by prolene suture.{Figure 2}

The endotracheal tube was removed the next day after surgery. He recovered uneventfully and was discharged from hospital 9 days after surgery. Before this child was discharged from the hospital, the follow-up transthoracic echocardiography showed only 7 mmHg of PG across LVOT. Currently, he is in functional class I of New York Heart Association and is drug-free. At 4-year follow-up, the PG across LVOT is 17 mmHg by transthoracic echocardiography, and the body weight increased to 23 kg.

 Discussion



TEE is a good method to check postoperative lesion after congenital cardiac surgery.[1],[2] However, infantile TEE is not the facility always available. Intraoperatively, it is difficult to check left ventricular pressure with needle puncturing because left ventricle is located posteriorly. Sometimes, it might be possible to check the left ventricular pressure using a long needle puncturing at right ventricle through ventricular septum into the left ventricle. By the needle puncturing technique, the surgeons do not have enough confidence about whether the pressure of the left ventricle is measured correctly or not because it cannot be sure where the needle tip is going. If no TEE available, placement of a catheter through ascending aorta through aortic valve into left ventricle can check the pressure of the left ventricle directly. Along with the pressure of ascending aorta measured through the root vent needle, the residual PG after surgery for subaortic stenosis can be evaluated in simply and accurate manner.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patients has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Kuralay E, Ozal E, Bingöl H, Cingöz F, Tatar H. Discrete subaortic stenosis: Assessing adequacy of myectomy by transesophageal echocardiography. J Card Surg 1999;14:348-53.
2Lim DS, Dent JM, Gutgesell HP, Matherne GP, Kron IL. Transesophageal echocardiographic guidance for surgical repair of aortic insufficiency in congenital heart disease. J Am Soc Echocardiogr 2007;20:1080-5.