MAPSE - ICUNOTES

Mitral Annular Plane Systolic Excursion (MAPSE)

MAPSE (Mitral Annular Plane Systolic Excursion) measures the distance the mitral annulus moves toward the LV apex during systole.

Unlike LVEF, which mainly reflects radial shortening, MAPSE reflects longitudinal myocardial fiber contraction i.e (LV) longitudinal systolic function, making it particularly sensitive for detecting early LV systolic dysfunction. It is recommended as an alternative when LVEF or GLS cannot be measured reliably because of poor image quality.

Table of Contents

Basic Concept

During systole:

LV apex remains relatively fixed.
Mitral annulus moves toward the apex.
This shortening represents longitudinal contraction.

The greater the annular displacement → the better the LV longitudinal function.

Physiology

LV contraction occurs in three directions:

1. Longitudinal shortening

2. Circumferential shortening

3. Radial thickening

Why MAPSE may be abnormal despite normal EF

EF mainly reflects

radial shortening
circumferential shortening

MAPSE reflects longitudinal shortening.

Compensation occurs—Radial fibers become hyperdynamic Therefore EF stays normal MAPSE decreases.

Therefore, Reduced MAPSE + normal EF = early LV systolic dysfunction.

What exactly is measured?

Distance (mm or cm) between Mitral annulus position at End diastole and End systole

Measured in

septal annulus
lateral annulus

Sometimes average of both.

How to Measure MAPSE

Echo View-Apical 4-chamber,Mode—M-mode

Cursor placement

Cursor through Mitral annulus and parallel to annular motion

Normal Values

Historically used cut-offs:

MAPSE	Interpretation
>1.2 cm (>12 mm)	Normal
1.0–1.2 cm	Borderline
<1.0 cm	Reduced longitudinal LV function
<0.8 cm	Severe dysfunction

Modern reference values

Large multicentre studies demonstrate:

Women have slightly higher MAPSE than men.
MAPSE declines gradually with age.
Age- and sex-specific reference values are preferable rather than a single universal cutoff.

Typical healthy adults: ≈ 12–16 mm

Determinant of MAPSE

Determinants	Explanation
Contractility	↑ Contractility → ↑ MAPSE. Stronger longitudinal LV shortening produces greater mitral annular excursion.
Preload	Higher preload → Slight ↑ MAPSE via the Frank–Starling mechanism. The effect is generally modest.
Afterload	Higher afterload → ↓ MAPSE because increased LV wall stress reduces longitudinal shortening.
Longitudinal Myocardial Fiber Integrity (Major determinant)	MAPSE primarily reflects function of the subendocardial longitudinal fibers. Diseases affecting these fibers (ischemia, fibrosis, cardiomyopathy) reduce MAPSE early, even when LVEF is preserved.
Age	MAPSE decreases with aging due to age-related decline in longitudinal systolic function despite preserved ejection fraction in many individuals.
Heart Rate	Minor effect. Within the physiological range, heart rate has little independent influence on MAPSE.
Blood Pressure	Higher systemic blood pressure → ↓ MAPSE, largely because of increased LV afterload.
Left Ventricular Size	Dilated LV → ↓ MAPSE. Ventricular remodeling and reduced longitudinal fiber function decrease annular excursion.

Clinical Pearl: MAPSE is load-dependent (especially influenced by preload and afterload) but is most strongly determined by the integrity of the LV longitudinal subendocardial fibers, making it a sensitive marker of early LV systolic dysfunction. These determinants have been confirmed in population-based echocardiographic studies.

Diseases affecting MAPSE

Disease	Effect on MAPSE & Mechanism
Ischemic Heart Disease (CAD/ACS)	Early ↓ MAPSE; one of the earliest echocardiographic markers of subendocardial ischemia, often before LVEF declines.
Hypertension	Chronic pressure overload causes subendocardial fibrosis and impaired longitudinal contraction → ↓ MAPSE.
Diabetes Mellitus	Diabetic cardiomyopathy with microvascular dysfunction and myocardial fibrosis preferentially affects longitudinal fibers → ↓ MAPSE.
Dilated Cardiomyopathy (DCM)	Markedly reduced (↓↓) MAPSE due to global LV systolic dysfunction and ventricular dilatation.
Heart Failure with Preserved EF (HFpEF)	Reduced MAPSE despite normal LVEF because longitudinal systolic dysfunction develops while radial function remains preserved.
Heart Failure with Reduced EF (HFrEF)	Markedly reduced MAPSE, correlating with the severity of LV systolic dysfunction and adverse prognosis.
Cardiac Amyloidosis	Very low MAPSE, often disproportionate to the relatively preserved LVEF seen in early disease due to severe longitudinal fiber involvement.
Hypertrophic Cardiomyopathy (HCM)	Reduced MAPSE despite normal or hyperdynamic LVEF, reflecting impaired longitudinal myocardial function.
Aortic Stenosis	Pressure overload leads to subendocardial ischemia and fibrosis → longitudinal dysfunction with ↓ MAPSE, often preceding a fall in EF.
Mitral Regurgitation (MR)	MAPSE is often preserved in early disease because of reduced afterload, but declines in advanced or decompensated MR as LV dysfunction develops.
Chemotherapy-Induced Cardiotoxicity	Early reduction in MAPSE, making it a useful marker of subclinical LV dysfunction before EF decreases.
Septic Cardiomyopathy	Frequently reduced MAPSE due to reversible myocardial depression and impaired longitudinal function.
Myocarditis	Reduced MAPSE secondary to myocardial inflammation and impaired contractility.
Post-CABG	Transient reduction in MAPSE is common after surgery due to myocardial stunning, altered septal motion, and pericardial effects; it often improves during recovery.

MAPSE vs EF

MAPSE	EF
Longitudinal function	Global systolic function
M-mode	Simpson biplane
Very fast	Time consuming
Less image dependent	Requires good endocardial border
Detects early dysfunction	Falls later
Excellent ICU tool	Standard parameter

Limitations

Limitation	Clinical Significance
Angle Dependency	M-mode cursor must be parallel to the longitudinal motion of the mitral annulus. An oblique cursor results in underestimation of MAPSE.
Regional Wall Motion Abnormalities (RWMA)	Localized dysfunction (e.g., septal infarction) may cause reduced septal MAPSE while lateral MAPSE remains normal. Measuring both septal and lateral MAPSE and averaging the values improves assessment.
Mitral Annular Calcification (MAC)	Annular calcification restricts annular mobility, leading to artificially low MAPSE despite preserved LV systolic function.
Prosthetic Mitral Valve	Prosthetic valves alter normal annular motion, making MAPSE less reliable as an indicator of LV longitudinal function.
Mitral Valve Repair	Annuloplasty rings and surgical repair modify mitral annular mechanics, potentially reducing MAPSE independent of true LV function.
Atrial Fibrillation	Beat-to-beat variation in preload causes variable MAPSE. Average measurements over at least 5 consecutive cardiac cycles for greater accuracy.
Cardiac Pacing (especially RV pacing)	Abnormal septal activation and dyssynchrony alter annular motion, reducing the reliability of MAPSE, particularly at the septal annulus.
Does Not Replace LVEF	MAPSE is a simple marker of longitudinal LV systolic function but does not replace comprehensive assessment. It should be interpreted alongside LVEF, tissue Doppler S′, GLS, regional wall motion, and overall echocardiographic findings.