Brief Answer:
Can be respiratory in origin also!

Detailed Answer:
Hi,
Firstly thanks for choosing health care magic for your query!

I have noted all your details,
Breathlessness in a 66 years old obese female who is having multiple diseases can be most commonly because of -
1)Coronary artery disease-As in your case your angiogram is normal,it can't be of cardiac origin.

2)Restrictive or obstructive lung disease-
Restrictive lung diseases are a category of extrapulmonary, pleural, or parenchymal respiratory diseases that restrict lung expansion, resulting in a decreased lung volume, an increased work of breathing, and inadequate ventilation and oxygenation. Hence causing serious breathlessness.

Obstructive lung disease is a category of respiratory disease characterized by airway obstruction. Mostly result from narrowing of the smaller bronchi and larger bronchioles, often because of excessive contraction of the smooth muscle itself. It is generally characterized by inflamed and easily collapsible airways, obstruction to airflow.

I would advice you to go for Pulmonary function tests-
Its a non-invasive test to check the functions of the lung.The tests measure lung volume, capacity, rates of flow, and gas exchange.Spirometry measures the amount and speed of air that can be inhaled and exhaled.
There are various parameters involved in it and hence a doctor can figure out whether it's obstructive lung disease or restrictive lung disease.

3)Over weight-278lbs is no doubt morbid obesity- In your case it can be Obesity hypoventilation syndrome better known as Pickwickian syndrome-a condition in which severely overweight people fail to breathe rapidly enough or deeply enough.However most of the patient present with breathing difficulty during sleeping ,yet severe breathlessness in performing normal activities have also been reported.

Once your pulmonary function tests are normal,your breathlessness can be attributed to your morbid obesity.

So ,yes these problems can be because of your morbid obesity but respiratory cause has to be ruled out first.When you were 40 you were young,muscles were young but as age progresses the functions and capacity of muscles and other organs decreases,hence they are causing more problem now.

Activity adviced-
Severe and strict Life style modification.
Avoid ;rather stop eating all junk food,If possible try to follow raw vegans diet for one time and regular normal food for other time.
Split your meals in small parts,take regular meals seperated by few hours.
Surgical options to control morbid obesity can be discussed from a surgeon.
Severe obesity is most likely a result of a combination of genetic, psychosocial, environmental, social and cultural influences that interact resulting in the complex disorder of both appetite regulation and energy metabolism. Severe obesity does not appear to be a simple lack of self-control by the patient.

-Roux-en-Y gastric bypass, gastric banding (adjustable or non-adjustable), sleeve gastrectomy, malabsorption procedures (biliopancreatic diversion, duodenal switch) and vertical banded gastroplasty, are a,mong few options available for patients suffering from morbid obesity.

Medical management-Trials have shown that very high dose of Betahistine 24mg taken thrice daily for almost 3 months have caused severe weight loses in patient(THEY ARE TRIAL DOSES AND ARE FAR ABOVE THE NORMAL THEURAPTIC DOSES,NEVER TRY IT BEFORE CONSULTING A DOCTOR BY YOURSELF).
Metformin (Anti-diabetic )medication have also been tried in high doses to control weight.
Please discuss them with your physician.

In case you have any other question feel free to ask!

Dr Rishu Saxena
Cardiologist

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