Table 1.

Underlying pathophysiologic mechanisms that affect LA size and function.

Pathophysiologic mechanism	Effect on LA	Examples of diseases and pathologic states
Pressure and/or volume overload	Hypertrophy, necrosis, apoptosis and fibrosis at cellular and extracellular matrix levels [1] Neurohumoral activation such as atrial natriuretic peptide (ANP) [1,18]	•LV systolic dysfunction (HFrEF) [3,4] •LV diastolic dysfunction (HEpEF) [5,6] •Ischemic heart disease [3,4] •Post-myocardial infarction [3,4] •Hypertension •Aortic stenosis •Aortic insufficiency •HCM [7] •Mitral stenosis •Mitral regurgitation •LV dilatation [3,4] •LV myocardial scar [3,4] •Iron deposition on the myocardium •Sarcoidosis •Amyloidosis •Obesity •LV hypertrophy on athletes •Aging •Dilated cardiomyopathies •Obstructive Sleep Apnea
Tachycardia		•AFib •Hyperthyroidism •Drug induced tachycardia •Energetic beverages •Caffeine in excess

Abbreviations: HFrEF: Heart failure with reduced ejection fraction, HEpEF: Heart failure with preserve ejection fraction, HCM: Hypertrophic cardiomyopathy, LV: Left ventricle, AFib: Atrial fibrillation.