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Difficulty in breathing while climbing or slight exertions simply indicates that your heart is unable to take this amount of load.
You need to give your body more rest , for now.
Also some investigations are required to chk the status of your heart at present. Please get in touch with your cardiologist.
Meanwhile avoid exertion, mental stress
, excess salt , sugar, saturated fats.
One more thing you must know, cardiac pain can radiate to right side of cheat as well. Other probabilities may be hyperacidity
, gastrooesophgeal reflux etc. Since you have a history of cardiac illness and symptoms are worse from exertion..its definitely your heart that is distressed.
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