From the Guidelines
Yes, Alanine Transaminase (ALT) can be elevated after a Myocardial Infarction (MI). While ALT is primarily associated with liver damage, it can rise following a heart attack due to several mechanisms. During an MI, reduced cardiac output can lead to decreased blood flow to the liver (hypoperfusion), causing secondary liver injury and ALT elevation. Additionally, heart failure resulting from MI may cause congestion in the liver, further contributing to enzyme release. The elevation is typically mild to moderate (usually less than 3 times the upper limit of normal) and transient, normalizing within days to weeks as the cardiac condition stabilizes. This elevation is often accompanied by increases in other liver enzymes like Aspartate Aminotransferase (AST), which is found in both heart and liver tissue. When evaluating elevated ALT after MI, clinicians should consider this cardiac-hepatic relationship while also ruling out other potential causes of liver enzyme elevation such as medication effects, pre-existing liver disease, or other acute conditions.
Key Points to Consider
- The most recent and highest quality study on myocardial infarction, the third universal definition of myocardial infarction 1, does not directly address ALT elevation but emphasizes the importance of cardiac biomarkers like troponin in diagnosing MI.
- The study from 2000, myocardial infarction redefined--a consensus document of the joint european society of cardiology/american college of cardiology committee for the redefinition of myocardial infarction 1, discusses the role of biomarkers in MI but does not specifically mention ALT.
- The elevation of ALT after MI is a clinical observation that requires consideration of the cardiac-hepatic relationship and the potential for other causes of liver enzyme elevation.
- The management of patients with elevated ALT after MI should focus on stabilizing the cardiac condition and addressing any underlying liver disease or other causes of enzyme elevation.
Clinical Implications
- Clinicians should be aware of the potential for ALT elevation after MI and consider this in the differential diagnosis of patients with elevated liver enzymes.
- The evaluation of elevated ALT after MI should include a thorough assessment of cardiac function, liver disease, and other potential causes of enzyme elevation.
- The management of patients with elevated ALT after MI should prioritize the stabilization of the cardiac condition and the treatment of any underlying liver disease or other causes of enzyme elevation.
From the Research
ALT Elevation after Myocardial Infarction
- Alanine Transaminase (ALT) can be elevated after a Myocardial Infarction (MI) 2, 3, 4, 5.
- Studies have shown that elevated ALT levels are associated with increased in-hospital all-cause mortality in patients with acute myocardial infarction (AMI) 2.
- ALT elevations are common in ST-elevation myocardial infarction (STEMI), with 48.2% of patients having elevated ALT levels at baseline or day 1 3.
- Elevated ALT levels are independently associated with worse mortality and clinical outcomes in patients with STEMI 3.
- The predictive value of ALT for mortality in patients with AMI has been demonstrated, with an adjusted odds ratio of 2.240 for ALT ≥ 2ULN 2.
Association with Cardiovascular Morbidity
- Elevated ALT levels are associated with an increased risk of cardiac death or acute myocardial infarction at 5-year follow-up, and all-cause mortality in patients with normal myocardial perfusion imaging (MPI) results 6.
- ALT levels are correlated with the presence of myocardial ischemia, but not significantly with abnormal MPI results 6.
Clinical Implications
- Elevated serum transaminases, including ALT, are common in patients with acute coronary syndromes (ACS) and may result in exclusions from clinical efficacy trials due to suspected liver disease 5.
- Current transaminase thresholds for liver dysfunction used in clinical trials may lead to excessive and inadequate exclusions of patients with larger infarcts from such trials 5.