Final answer:
If a marijuana abuser has already suffered a heart attack, they would likely experience increased cardiovascular risks. Similar to the effects of smoking tobacco, marijuana can alter heart rate, increase blood pressure, and contain substances with adverse cardiovascular effects.
Step-by-step explanation:
If a marijuana abuser has already suffered a heart attack, he or she would likely experience increased cardiovascular risks according to the text. The consumption of substances like marijuana can have multiple adverse effects on the cardiovascular system.
In the context of smoking, the inhalation of smoke itself has immediate responses in the heart and blood vessels. For example, smoking tobacco can significantly increase heart rate, raise blood pressure, cause blood clot formation, and limit the blood's oxygen-carrying capacity, which substantially elevates the risk of another heart attack or stroke. Although marijuana is different from tobacco, it also contains substances that can have similar cardiovascular effects.