Cardiac Remodelling in Athletes: Concentric vs Eccentric Hypertrophy Summary

Cardiac Remodelling: Concentric vs. Eccentric Hypertrophy

Cardiac Remodelling Definition

Defined as a physiological or pathological state after conditions like myocardial infarction or volume overload.
In athletes, it's a physiological adaptation to excessive training, causing changes in heart size and shape.

Physiological vs. Pathological Remodelling

Physiological Remodelling: Compensatory changes seen in athletes.
Pathological Remodelling: Occurs after myocardial infarction or in dilated cardiomyopathy.
Cardiomyocytes: Expand via synthesis of contractile proteins and sarcomeres to increase contractile force.

Endurance vs. Strength Training

Endurance Training:

Associated with increased cardiac output and volume load.
Causes mild to moderate left ventricle dilatation and increased wall thickness.
Leads to eccentric hypertrophy: new sarcomeres added in-series.
Cardiac output may increase from 5-6 L/min at rest to 40 L/min during maximal exercise.

Strength Training:

Characterized by elevated systolic and diastolic blood pressure.
Causes increased left ventricular wall thickness, possibly with a slight volume increase.
Leads to concentric hypertrophy: new sarcomeres added in-parallel.
Blood pressure during weightlifting can reach as high as 320/250 mmHg.

Morphological Changes in Athletes

Endurance athletes show increased left ventricular wall thickness and cavity size.
Cyclists may experience left ventricle and atrium dilatation early in their careers.

Key Findings

Runners predominantly show increased left ventricular wall thickness.
Cyclists primarily demonstrate dilatation of the left ventricle.
Strength-trained athletes show increased myocardial mass, sometimes without a significant volume increase.

Conclusion

Both strength and endurance training cause left ventricular hypertrophy.
Left ventricular wall thickness is greater in strength training.
Dilatation of the left ventricle is more prominent in endurance training.