People who consume heavy amounts of alcohol are at an increased risk of developing various health conditions. Option 1, blood cancer, is not directly linked to heavy alcohol consumption. Option 3, liver or stomach cancer, is indeed a potential consequence of heavy alcohol use, but it is not the leading cause of death in these individuals. Option 4, weakening of heart muscles leading to cardiac arrest, may occur in some cases, but it is not the primary cause of death among heavy alcohol consumers.

The correct answer is option 2, cirrhosis. Cirrhosis is a serious condition where the liver becomes scarred and damaged due to chronic alcohol abuse. Over time, this damage can lead to liver failure and ultimately death. Cirrhosis is a major cause of mortality among heavy alcohol consumers, making it the most likely cause of death in this population.