From the Guidelines
Cardiac hypertrophy should be diagnosed and managed according to the latest guidelines, which define it as a disease state characterized by left ventricular hypertrophy (LVH) in the absence of another cardiac, systemic, or metabolic disease capable of producing the magnitude of hypertrophy evident in a given patient, with a maximal end-diastolic wall thickness of ≥15 mm anywhere in the left ventricle in adults, as stated in the 2024 AHA/ACC/AMSSM/HRS/PACES/SCMR guideline 1.
Diagnosis and Clinical Presentation
The diagnosis of cardiac hypertrophy, particularly in the context of hypertrophic cardiomyopathy (HCM), can be established through imaging techniques such as 2D echocardiography or cardiovascular magnetic resonance (CMR), showing a maximal end-diastolic wall thickness of ≥15 mm anywhere in the left ventricle in adults, in the absence of another cause of hypertrophy 1. For children, the diagnostic criteria are adjusted for body size and growth, with a proposed threshold of a z-score >2.5 for asymptomatic children with no family history, and a threshold of a z-score >2 for children with a definitive family history or a positive genetic test 1.
Management and Treatment
Management of cardiac hypertrophy focuses on addressing the underlying cause, which may include controlling blood pressure with medications, managing valve disease, or treating other cardiac conditions 1. Lifestyle modifications such as sodium restriction, regular moderate exercise, and weight management are also crucial in managing the condition. In severe cases, more aggressive interventions may be necessary, such as valve replacement surgery or consideration of heart transplantation in end-stage heart failure.
Importance of Early Detection
Early detection and management of cardiac hypertrophy are vital, as untreated cardiac hypertrophy can progress to heart failure, arrhythmias, and increased risk of sudden cardiac death 1. The emergence of the HCM phenotype in younger family members who carry a pathogenic or likely pathogenic variant without previously evident LVH at initial screening underscores the importance of regular monitoring and screening in high-risk individuals 1.
Key Considerations
- Diagnosis: Should be based on the latest guidelines, considering the maximal end-diastolic wall thickness and the absence of another cause of hypertrophy.
- Management: Should focus on addressing the underlying cause and include lifestyle modifications.
- Early Detection: Is crucial to prevent progression to more severe cardiac conditions.
- Family History and Genetic Testing: Play a significant role in the diagnosis and management of cardiac hypertrophy, especially in younger individuals.
From the Research
Definition and Characteristics of Cardiac Hypertrophy
- Cardiac hypertrophy is a response of the heart to increased workload, a cardiac insult such as a heart attack or genetic mutation 2.
- It is characterized by an increase in cardiomyocyte size and thickening of ventricular walls 2, 3.
- Initially, cardiac hypertrophy is an adaptive response to maintain cardiac function, but it can become maladaptive and lead to heart failure over time 2, 3.
Pathogenesis and Signaling Pathways
- The pathogenesis of cardiac hypertrophy involves numerous mediators, including signaling proteins, microRNAs, long noncoding RNAs, and calcineurin and calcium-/calmodulin-dependent protein kinases 2.
- Oxidative stress is a critical inducer of both genetic and acquired forms of cardiac hypertrophy 4.
- Metabolic disturbances, mitochondrial dysfunction, inflammation, and dysregulated autophagy and protein homeostasis contribute to disease pathophysiology through mechanisms involving oxidative stress 4.
Treatment and Management
- Treatment strategies for heart failure, including cardiac hypertrophy, commonly include diuretics, angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, and β-blockers 2, 5.
- Lifestyle interventions, such as diet, physical activity, and stress reduction, may improve outcomes for cardiovascular disease patients, including those with cardiac hypertrophy 6.
- Novel therapeutic approaches, including RNA-based therapies, dietary supplementation, and small molecules, are being developed to target cardiac hypertrophy and heart failure 2, 4.
Types of Cardiac Hypertrophy
- Cardiac hypertrophy can be classified as physiological or pathological, depending on whether it is associated with normal cardiac function or cardiac dysfunction 3.
- Physiological hypertrophy occurs in response to normal growth or exercise, while pathological hypertrophy is induced by factors such as hypertension or myocardial infarction 3.