Home > Heart Surgery Blog > Recovery > "Why Is My Husband Gaining Weight From Fluids After Heart Valve Surgery?" Asks Joanie

"Why Is My Husband Gaining Weight From Fluids After Heart Valve Surgery?" Asks Joanie

Written By: Adam Pick, Patient Advocate, Author & Website Founder
Medical Expert: Lawrence Cohn, MD, Brigham & Women's Hospital
Page Last Updated: July 8, 2025

I just received an interesting question from Joanie. She writes, "Hi Adam - My husband had mitral valve repair surgery three days ago. I noticed that he's gained 8 pounds since the surgery. The doctors say the gain is due to fluid intake. Is this common? What fluids did they use? How long until he loses the fluid? Thanks, Joanie."

While I had my thoughts on the topic, I wanted to provide Joanie an expert opinion. That said, I contacted Dr. Larry Cohn, MD, who practices at Brigham & Women's Hospital in Boston. During his 40-year career, Dr. Cohn has performed over 10,000 cardiac procedures.

Dr. Larry Cohn - Brigham & Women's Hospital

In his response to Joanie's question about weight gain after heart surgery, Dr. Cohn shared, "Retention of fluid following all forms of heart surgery, especially mitral valve surgery, is very common. This is because in most institutions, like Brigham & Women's, no blood is used and it is mostly saline in the heart lung machine to dilute the patients blood elements, thus causing some fluid retention. Also, surgery causes some hormonal changes which can cause fluid retention. Thus, it is extremely common for people to gain weight following open heart surgery of any kind, especially mitral valve surgery. This can be even worse if the patient has been in heart failure prior to the surgery where these changes will be even more magnified post-operatively."

He also noted, "The judicious use of diuretics postoperatively, quickly releases this fluid from the edematous tissues and the patient excretes this extra water out within a few days. Edema like this should be gone in approximately three weeks at the very latest."

Written by Adam Pick - Patient & Website Founder

Adam Pick is a heart valve patient and author of The Patient's Guide To Heart Valve Surgery. In 2006, Adam founded HeartValveSurgery.com to educate and empower patients. This award-winning website has helped over 10 million people fight heart valve disease. Adam has been featured by the American Heart Association and Medical News Today.

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