Likewise, smoking also increases blood pressure and the heart rate, which means that the body will need more oxygen. The heart will have to work faster to obtain the necessary oxygen, which is in poor supply due to the effects of the carbon monoxide from the smoke and this will therefore lead to stress on the heart, which could cause angina or a sudden heart attack.
http://www.erowid.org/plants/cannabi...is_info3.shtml
http://www.helpwithsmoking.com/smoki...-the-heart.php
tl;dr version:
get your blood pressure checked