Follow-up on new marker confirming the optimal status in the treatment of heart failure with reduced ejection fraction
Authors: Tran L.E , Nguyen T , Pham H.O.A , Thai M.I.N.H , Nguyen L.O.C , Truong H.U.Y , Cao B.I.N.H 
Published: October 2021

Abstract

Background
At the present time, there is no strong criterion to guarantee the optimal management for patients with heart failure and reduced ejection fraction (HFrEF). In the past, our group suggested the use of the size of the femoral vein (FV), measured by ultrasound as a marker of the fluid status in the venous compartment. Is this criterion still the best marker of optimal treatment of HFrEF at 3 years follow-up, especially for patients with significant co-morbidities (chronic obstructive pulmonary disease (COPD), end stage renal disease (ESRD) on hemodialysis (HD), cirrhosis of liver or sepsis?

Methods
Patients with HFrEF and co-morbidities as above were enrolled. All patients had echocardiography to confirm EF &lt;45% and underwent the ultrasound test to assess the size and expansibility of the femoral vein (SEFV). The SEFV is the ultrasound study of the FV examining its size and expansibility with cough. The location of the femoral artery (FA) and FV to be checked is the coronal plane immediately proximal to the bifurcation of the superficial and deep femoral artery. The normal size of FV is a little larger than of the FA. If the size of the FV is twice larger than the FA, the patient has fluid overload in the venous compartment (Figure 1). Then the patient was asked to cough in order to measure the size of the FV. If the FV did not increase its size with cough, the venous compartment was full. If the FV increased its size, the venous compartment was not full and could accommodate more fluid. In physical exam, the fluid overload is proved by the presence of extravascular fluid in the abdominal wall, ascites or leg edema or in the intravascular compartment by the presence of the jugular venous distention. During the 3 years of follow-up, the patients were seen in the office and had the SEFV at regular 6 months intervals. A small group of patients also underwent right heart catheterization to measure to the pulmonary capillary wedge pressure (PCWP).

Results
180 patients with HFrEF and significant comorbidities were enrolled. All patients were taught to follow a low Na diet, &lt;2000cc of fluid restriction and the guideline directed medical therapy. After about 3 years, 75% patients in the study group were asymptomatic, was not readmitted to the hospital for HF, and the size of the FV was within normal range. Their physical exam showed no fluid in the extravascular compartment. The PCWP became lower than 24mmHg in 18/20 who underwent the RHC. There was significant weight loss (15 lbs). In the control group, 60% of patients were asymptomatic and 50% were not readmitted for HF (p&lt;0.05).

Conclusions
With the SEFV test, the patients with HFrEF and significant comorbidities were accurately estimated for presence or absence of fluid overload. This SEFV test was especially sensitive to detect fluid overload in patients with multiple co-morbidities. Further randomized trials are needed to confirm the above preliminary results.

Funding Acknowledgement
Type of funding sources: None. Figure 1. Enlarged size of femoral vein