— Andrew Perry, MD, delves into its role with Radha Gopalan, MD
It’s a Catch-22: morbid obesity can keep patients with advanced heart failure from getting a new heart, but advanced heart failure can also keep them from getting weight loss surgery.
How can clinicians manage such patients? Andrew Perry, MD, finds out in this episode of the AP Cardiology podcast through a conversation with Radha Gopalan, MD, of Banner-University Medical Center in Phoenix.
Perry: In this episode, I am visiting with Dr. Gopalan from Banner University in Phoenix to discuss bariatric surgery in patients with heart failure. He shares an interesting experience and perspective of working with morbidly obese patients who are declined from heart transplant due to their obesity. We discuss the risks of the surgery and the benefits of bariatric surgery on functional capacity. I thought it was super interesting and hope you do so as well. Thanks for listening.
Perry: This is AP Cardiology and this is your host, Andrew Perry. Thank you for meeting with me today, Dr. Gopalan. Can I have you say your name and your title for our listeners?
Gopalan: Thank you, Andrew. I’m Dr. Radha Gopalan. I’m the Medical Director of Heart Transplantation, Mechanical Circulatory Support, Total Artificial Heart, and Advanced Heart Failure at Banner-University Medical Center in Phoenix, Arizona.
Perry: Perfect. Thank you. I am visiting with you today about a topic that doesn’t get a lot of attention. We had some questions regarding bariatric surgery in patients with heart failure, so to frame our discussion I’m going to present a case.
We saw a 55-year-old woman with obesity, a BMI of 38, who is insulin-dependent diabetes and hypertension, and she presents with a few months of exertional dyspnea and fatigue. During her workup, she ends up getting a resting echocardiogram demonstrating a normal ejection fraction of 55%, and the diastology, when you look at it, is most consistent and suggests elevated left atrial filling pressures. She’s put up with a diagnosis of heart failure with preserved ejection fraction.
As a lot of people know, the heart failure with preserved ejection fraction, a lot of these patients are fairly obese. My first question for you is how obesity can contribute to heart failure, both preserved and reduced ejection fraction?
Gopalan: I’m glad to note that you had framed the BMI at 38, and actually, that falls into morbid obesity paradigm. Heart failure has different ways of looking at obesity, so I’m going to quickly just give you an overview of how we look at patients with heart failure who are obese.
Gopalan: Obviously, we like patients that have a BMI less than 30, ideal for our situation. But when patients’ BMI falls between 30 and 35, we have this obesity paradox concept where the obesity itself appears to protect these women and men with regard to the adverse effects of heart failure with regard to mortality and morbidity.
But most of the studies of retrospective analysis have shown that once you cross a BMI of 35, then the adverse effects are enhanced or increased. They don’t do well from a morbidity and mortality perspective. Their hospitalization increases, the trajectory and rapidity of clinical deterioration increases, and they just don’t do well. There are several reasons for that and I think that is still being explored.
Having said that, how does obesity contribute? One of the issues, especially looking at obesity, is it’s a metabolic disease process. So as a result of metabolic alterations, especially these patients tend to have other comorbidities such as obstructive sleep apnea, diabetes mellitus, either insulin-dependent or non insulin-dependent, and hypertension. When we looked at this… interestingly, you framed the patient at age 55.
Hypertension, men tend to have more hypertension under age 45 and then women start getting more. Incidence of hypertension in women increases as the age increases, and then they surpass men after age 65 in having hypertension. As a result of it, if you extrapolate that, they have heart failure with preserved ejection fraction incidence higher as the age progresses in women.
Having said that, the molecular etiologies and pathways that lead to heart failure with preserved ejection fraction in men and women with obesity is still in the exploratory phase where we are trying to figure out what pathways exactly lead to heart failure as such. In clinical experience, we come across both. We do have patients who have morbid obesity and don’t have heart failure; and we do have patients who have obesity and have heart failure.
Obviously, obesity is one of the contributing factors, but we are beginning to think obesity is a manifestation of a similar molecular and neurohormonal pathway that leads to heart failure. We are in the clinical phase, as specialists, looking to see — the obesity is as much of a manifestation as heart failure is a manifestation of probably the same underlying molecular pathway alterations or genetic alterations. That is the thought process.
Perry: Interesting. I guess that frames that concept a bit differently as opposed to obesity being a risk factor and perhaps a driving causative mechanism. But you’re suggesting that there may be a separate underlying mechanism that results in both obesity and heart failure. Is that correct?
Gopalan: Correct, and I think what I’m trying to say is the mechanism that drives obesity also contributes to heart failure rather than you have to first develop obesity to have heart failure.
Perry: Gotcha. Very interesting. Okay. I had not heard that.
Related to obesity, it’s hard to help patients and guide them along weight loss programs and strategies through either pure lifestyle changes and/or assistance with medications. That’s where bariatric surgery has come in and has been a huge player in patients, at least in terms of non-heart failure patients, just a pure obesity population, in helping with large amounts of weight loss and sustained weight loss over long periods of time. One question with these overlapping paradigms of obesity and heart failure is a question of whether bariatric surgery in patients with heart failure with preserved ejection fraction would improve their clinical outcomes, such as heart failure hospitalizations and/or even survival.
Gopalan: Interesting question. One of the things that… as you can see in heart failure, the obesity now is in the radar for us. Especially in our program, we have been successful in performing bariatric surgery in patients with severely reduced ejection fraction. Those are patients who are normally turned down by most of the bariatric programs as being high-risk. As a result of this… and I’m going to share with you some of the observations as an advanced heart failure guy and the difficulties we have faced, which will sort of set the tone for the subsequent discussion.
What we find is that we have women and men, mostly women… and I’m going to say most women tend to… the incidence of obesity in women is more than in men. Most women who have obesity, because of the physiology differences, they tend to have more heart failure with preserved ejection fraction, as opposed to men having heart failure with reduced ejection fraction. That’s because of the physiology difference.
The physiology difference is one of those that have been identified being women with obesity, or even without obesity, any afterload stressors such as hypertension or other afterload stressors, women tend to develop concentric hypertrophy as opposed to men who have eccentric hypertrophy of the heart.
There is a difference. Eccentric hypertrophy mostly leads to systolic dysfunction and concentric tends to, at least at the initial phases, before it becomes burned out, results in preserved ejection fraction. But nevertheless both are heart failure. Read the full article https://www.medpagetoday.com/podcasts/ap-cardiology/89456