Temporary Arteriovenous Fistula Compression for Clinical Decision-Making in Patients on Hemodialysis With Significant Aortic Stenosis.

https://e-jcvi.org A 57-year-old woman complained of dyspnea of New York Heart Association (NYHA) class III–IV and was transferred for surgery for severe degenerative aortic stenosis (AS). She had past history of chronic kidney disease on hemodialysis and hypertension. Initial echocardiography revealed moderate to severe degenerative AS with severe resting pulmonary hypertension (PH) and preserved left ventricular ejection fraction. Right heart catheterization was performed to find the cause of PH. The results showed combined post-capillary and pre-capillary PH with elevated cardiac index (CI) to 4.28 L/min/m2 (Table 1). Considering these results, the patient underwent intensive hemodialysis to reduce intravascular volume. However, AS peak jet velocity (Vpeak) was still high of 4.7 m/s with severe resting PH after volume reduction (Figure 1A). While evaluating causes of elevated CI, we found arteriovenous fistula (AVF) with high access flow rate (Figure 2). To determine the effects of increased transvalvular flow on measured parameters, we temporarily compressed AVF with blood pressure cuff to reduce shunt flow during echocardiography. During compression, Vpeak of aortic valve decreased to 3.6 m/s (Movies 1 and 2). The patient had revision of AVF to reduce shunt flow. After revision, echocardiography revealed moderate AS (Vpeak: 3.4 m/s) with mild resting PH (Figure 1B) and dyspnea was improved to NYHA class II. Continuity equation valve area was the same before and after surgery with value of 1.1 cm2 (Figure 3). High-flow state can overestimate AS severity.1) Causes of high-flow state should be identified and severity should be re-assessed when normal flow is restored.2) Temporary compression of AVF may be used for this purpose.1) J Cardiovasc Imaging. 2023 Apr;31(2):118-120 https://doi.org/10.4250/jcvi.2022.0088 pISSN 2586-7210·eISSN 2586-7296