Can Coronary Artery Disease (CAD) be considered a sequela of Myocardial Infarction (MI)?

From the Guidelines

No, coronary artery disease (CAD) is not considered a sequela of myocardial infarction (MI); rather, the relationship is the opposite. CAD is the underlying condition that typically causes MI, as supported by the 2017 AHA/ACC clinical performance and quality measures for adults with ST-elevation and non-ST-elevation myocardial infarction 1. Coronary artery disease develops when the coronary arteries become narrowed or blocked due to atherosclerosis, which is the buildup of cholesterol, fat, calcium, and other substances in the arterial walls. This progressive narrowing restricts blood flow to the heart muscle. When a coronary artery becomes severely or completely blocked, often due to plaque rupture and subsequent blood clot formation, it causes a myocardial infarction (heart attack) 1.

The classification of MI, as outlined in the 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes 1, further emphasizes the role of CAD in the development of MI. Type 1 MI, which is spontaneous MI related to atherosclerotic plaque rupture, ulceration, fissuring, erosion, or dissection, is the most common type of MI and is directly related to CAD.

After an MI, patients may develop true sequelae such as heart failure, arrhythmias, ventricular aneurysms, or post-MI syndrome. Management of CAD includes lifestyle modifications, medications like statins, antiplatelets, beta-blockers, and ACE inhibitors, and possibly revascularization procedures. Understanding this relationship is crucial because treating the underlying CAD is essential for preventing initial or recurrent MIs. Key aspects of CAD management and MI prevention are highlighted in recent guidelines, including the importance of aspirin therapy in acute MI management, as noted in the 2017 AHA/ACC clinical performance and quality measures 1.

Some key points to consider in the management and prevention of MI in the context of CAD include:

• The use of aspirin as first-line therapy for acute MI, with a loading dose followed by a daily maintenance dose to minimize bleeding risk 1.
• The role of lifestyle modifications and medications in managing CAD and preventing MI.
• The potential for revascularization procedures in selected patients with CAD.

Overall, recognizing CAD as the underlying cause of MI, rather than a sequela, is critical for effective management and prevention of myocardial infarction.

From the Research

CAD as a Sequelae of MI

• CAD (Coronary Artery Disease) can be considered a sequelae of MI (Myocardial Infarction) as MI can lead to complications that increase the risk of developing CAD.
• According to 2, MI can lead to various complications, including those that can be diagnosed using cross-sectional imaging, which can have a significant impact on patient outcomes.
• The development of CAD after MI can be influenced by factors such as delayed or inadequate treatment, as well as the presence of other cardiovascular risk factors.

Relationship between MI and CAD

• Studies have shown that patients with MI are at increased risk of developing CAD, and that the use of certain medications such as aspirin, beta-blockers, statins, and ACE inhibitors can help reduce this risk 3, 4.
• The diagnosis and management of patients with suspected acute MI is crucial in preventing the development of CAD, and involves the use of various diagnostic tests and treatments, including troponin T or I, echocardiography, and cardiac MR or multidetector CT 5.
• The type of MI, such as MI type 2, can also play a role in the development of CAD, and may require a multi-disciplinary approach to treatment, including cardiology and secondary prevention therapies 6.

Prevention and Treatment

• Prevention and treatment of CAD after MI involves the use of evidence-based guidelines, including the use of antiplatelet drugs, beta-blockers, statins, and ACE inhibitors or ARBs 4.
• The prevalence of use of these medications in older patients with CAD in an academic nursing home has been shown to be high, with 98% of patients using aspirin or clopidogrel, 96% using beta-blockers, 87% using statins, and 85% using ACE inhibitors or ARBs 4.