Brief Answer:
causes inflammation ,abnormal function of heart

Detailed Answer:
HI, thanks for using healthcare magic

Cannibis has different effects on the body. In some instances it may have a positive effect , in others a negative effect.

In terms of CHF (chronic heart failure) and other heart diseases , it is thought that cannibis can cause changes (increases) in blood pressure and the heart rate.

In addition to increases in the heart rate ,it can causes other changes in the heart rhythm.

At present medical studies have focussed on the risk of a heart attack and stroke , there are not a lot of studies looking in to the effect in heart failure.
Heart failure occurs when the heart is not able to function specifically to XXXXXXX the demands of the body. If cannibis affects blood pressure and heart rate, both of which can affect the ability of the heart to function then it is likely that it would have an adverse affect in heart failure.

As mentioned there are not a lot of studies looking specifically at heart failure and cannibis some that have been done suggest that the use of cannibis can cause inflammation of the heart, death of some of the cells and prevent the heart from working properly.

It would be best not to use this if there is a history of heart disease.

I hope this helps, feel free to ask any additional questions

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