[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Physiology](https://durgical.com/en/physiology/) › [Cardiovascular](https://durgical.com/en/physiology/areas/cardio/) › How the circulation adapts to valve disease: aortic and mitral lesions at rest and in exercise

# How the circulation adapts to valve disease: aortic and mitral lesions at rest and in exercise

- Mechanism
- Exam priority: medium

A narrow or leaky valve makes the heart work harder. The heart grows and blood volume rises, which works until exercise or time uncovers the limit.

Updated Nov 13, 2026

Also called: Hemodynamics of valve disease, Phonocardiogram

**See it in 3D:** [Mitral anterior leaflet](https://durgical.com/en/anatomy/anterior-leaflet-of-left-atrioventricular-valve/) · [Aortic right coronary cusp](https://durgical.com/en/anatomy/right-coronary-leaflet/) · [Left atrium](https://durgical.com/en/anatomy/left-atrium/) · [Left ventricle](https://durgical.com/en/anatomy/left-ventricle/)

## Key points

- Aortic stenosis: pressure overload → concentric LV hypertrophy; LV pressure may reach ≈ 300 mmHg while aortic pressure stays normal.
- Aortic regurgitation: volume overload → eccentric hypertrophy and a very large stroke volume; low diastolic pressure lowers coronary perfusion.
- In aortic lesions the hypertrophied muscle needs more O₂ while coronary supply is limited: exertional angina; syncope comes from fixed output in exercise.
- Mitral stenosis: left atrial pressure rises → pulmonary congestion and edema (above ≈ 25 mmHg), a large left atrium and atrial fibrillation.
- Blood volume increases in valve disease (renal retention plus more red cells), which raises venous return and helps keep output up.
- Heart sounds and murmurs differ in frequency: valve closure sounds are short, murmurs are longer and contain higher frequencies; a phonocardiogram records them.

## What it is

Valve lesions overload the chamber behind them with pressure (stenosis) or volume (regurgitation). The left ventricle compensates by hypertrophy and the kidneys by retaining fluid, which keeps output near normal at rest for years. Exercise, which needs a quick rise in output, unmasks the lesion first; the left atrium and lungs suffer in mitral disease, the coronary supply in aortic disease.

## How it works, step by step

- A stenotic valve raises the pressure the chamber must generate; a regurgitant valve adds back-flow that must be pumped again.
- Pressure load adds sarcomeres in parallel (thick wall, concentric hypertrophy); volume load adds them in series (large chamber, eccentric hypertrophy).
- Low output reduces renal perfusion, so the kidneys retain salt and water; volume rises by ≈ 10–20% and red cell mass increases slightly.
- Higher volume and filling pressure keep output near normal at rest (Frank–Starling), but cardiac reserve shrinks.
- In aortic lesions, thick muscle and high wall stress need more O₂ while coronary inflow is limited (low diastolic pressure in AR, compression in AS): ischemia.
- In mitral stenosis flow is limited by the orifice; atrial pressure rises, and in exercise tachycardia shortens diastole, raising atrial pressure further.
- Exercise needs output to rise several-fold; a fixed obstruction or large leak cannot follow, so dyspnea, angina or syncope appear first on exertion.

### Left-ventricular pressure–volume loop

**EDV** 115 mL **ESV** 51 mL **SV** 64 mL **EF** 56% **ESP** 206 mmHg **LV peak** ≈ 222 mmHg

#### Aortic stenosis

Aortic stenosis: the LV must build a very high systolic pressure to push through the narrow valve (the aorta sees much less); the loop is tall, SV tends to fall and concentric hypertrophy stiffens filling.

Tap a corner of the loop (MC, AO, AC, MO) to see the valve event.

- Current loop
- Normal loop
- ESPVR (contractility, Ees)
- EDPVR (passive filling)
- Ea (arterial afterload)
- Stroke volume (SV)

Aortic stenosis: a tall, narrow loop from high LV pressure. Switch to mitral regurgitation to compare.

### Left-ventricular pressure–volume loop

**EDV** 170 mL **ESV** 56 mL **SV** 114 mL **EF** 67% **ESP** 116 mmHg **Regurgitant** ≈ 51 mL **Forward SV** ≈ 63 mL

#### Mitral regurgitation

Mitral regurgitation: the LV also ejects into the atrium from the start of contraction until it relaxes, so there are no true isovolumetric phases. EDV and total SV are large, but almost half goes back to the atrium: EF overstates function.

Tap a corner of the loop (MC, AO, AC, MO) to see the valve event.

- Current loop
- Normal loop
- ESPVR (contractility, Ees)
- EDPVR (passive filling)
- Ea (arterial afterload)
- Stroke volume (SV)

Illustrative model drawn by Durgical (time-varying elastance: ESPVR, EDPVR and Ea); values are approximate and not for clinical decisions.

## Sound frequencies (illustrative)

| Parameter | Value | Note |
| --- | --- | --- |
| S1 and S2 | ≈ 40–500 Hz | short, ≈ 0.10–0.14 s each |
| S3 and S4 | ≈ 20–40 Hz | low-pitched, best heard with the bell |
| Murmurs | up to ≈ 1000 Hz | longer, from turbulent flow |

Approximate values for a healthy adult at rest; each laboratory sets its own ranges.

## Typical adaptations

| Lesion | Load | Main compensation | First limit |
| --- | --- | --- | --- |
| [Aortic stenosis](https://durgical.com/en/conditions/aortic-valve-stenosis/) | Pressure on LV | Concentric LVH | Exertional angina, syncope, later failure |
| [Aortic regurgitation](https://durgical.com/en/conditions/aortic-regurgitation/) | Volume on LV | Eccentric LVH, large stroke volume | Low diastolic pressure, coronary shortfall, LV dilation |
| [Mitral stenosis](https://durgical.com/en/conditions/mitral-stenosis/) | Pressure on LA and lungs | LA dilation, higher volume | Pulmonary edema, atrial fibrillation, pulmonary hypertension |
| [Mitral regurgitation](https://durgical.com/en/conditions/mitral-regurgitation/) | Volume on LA and LV | LA and LV dilation | Pulmonary congestion, atrial fibrillation |

## Clinical notes

- Rheumatic heart disease, still common in Colombia, mainly affects the mitral valve and causes mitral stenosis years after streptococcal infection.
- Atrial fibrillation in mitral stenosis removes the atrial kick and shortens filling, which can sharply worsen pulmonary congestion.
- Exertional angina, syncope and dyspnea mark severe aortic stenosis.

## Memory aid

Stenosis builds walls, regurgitation builds rooms.

## Test yourself

Think of the answer, then tap the question to see it.

## Why does severe aortic stenosis cause angina even with normal coronary arteries?

The hypertrophied LV has high O₂ demand and high wall stress, while coronary inflow is limited by compression of subendocardial vessels and high diastolic LV pressure.

## Why does aortic regurgitation lower coronary perfusion?

Blood falls back into the ventricle in diastole, so aortic diastolic pressure, the main driving pressure for LV coronary flow, is low.

## A patient with mitral stenosis develops atrial fibrillation at 140/min and becomes very dyspneic. Why?

Fast rate shortens diastole and loss of the atrial kick lowers flow across the narrow valve; left atrial pressure rises and fluid enters the lungs.

## Why does blood volume rise in chronic valve disease?

Reduced output lowers renal perfusion, so the kidneys retain salt and water (and red cell mass rises slightly), raising venous return and output.

[Add to my cards (4)](https://durgical.app/estudiar/?add=/en/physiology/how-the-circulation-adapts-to-valve-disease-aortic-and-mitral-lesions-at-rest-an/)

[More Physiology questions →](https://durgical.com/en/practice/?f=physiology)

## Connections

## See it in 3D 4

The structures of Durgical's 3D anatomy where it happens.

- [Mitral anterior leaflet](https://durgical.com/en/anatomy/anterior-leaflet-of-left-atrioventricular-valve/)
- [Aortic right coronary cusp](https://durgical.com/en/anatomy/right-coronary-leaflet/)
- [Left atrium](https://durgical.com/en/anatomy/left-atrium/)
- [Left ventricle](https://durgical.com/en/anatomy/left-ventricle/)

## Related topics 5

- [Murmurs and the hemodynamics of valve disease](https://durgical.com/en/physiology/murmurs-and-the-hemodynamics-of-valve-disease/)
- [Heart sounds and where they come from](https://durgical.com/en/physiology/heart-sounds-and-where-they-come-from/)
- [The ventricular pressure–volume loop](https://durgical.com/en/physiology/the-ventricular-pressure-volume-loop/)
- [Coronary circulation and myocardial ischemia](https://durgical.com/en/physiology/coronary-circulation-and-myocardial-ischemia/)
- [Physiology of pulmonary edema](https://durgical.com/en/physiology/physiology-of-pulmonary-edema/)

## Related conditions 6

- [Aortic Valve Stenosis](https://durgical.com/en/conditions/aortic-valve-stenosis/)
- [Aortic regurgitation](https://durgical.com/en/conditions/aortic-regurgitation/)
- [Mitral stenosis](https://durgical.com/en/conditions/mitral-stenosis/)
- [Mitral regurgitation](https://durgical.com/en/conditions/mitral-regurgitation/)
- [Rheumatic heart disease](https://durgical.com/en/conditions/rheumatic-heart-disease/)
- [Atrial fibrillation](https://durgical.com/en/conditions/atrial-fibrillation/)

[← All of physiology](https://durgical.com/en/physiology/)

Educational physiology content; not a diagnostic or treatment guide and no substitute for a health professional's advice. Values are approximate references. No doses are given.

Sources: [Aortic Stenosis](https://www.ncbi.nlm.nih.gov/books/NBK557628/) (StatPearls (NCBI Bookshelf), 2025); [Aortic Insufficiency](https://www.ncbi.nlm.nih.gov/books/NBK557428/) (StatPearls (NCBI Bookshelf), 2024); [Mitral stenosis: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/000175.htm) (MedlinePlus, US National Library of Medicine, 2026); [Rheumatic Heart Disease](https://www.ncbi.nlm.nih.gov/books/NBK538286/) (StatPearls (NCBI Bookshelf), 2023).

## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake

Representative model, for educational purposes only.

---
Source: https://durgical.com/en/physiology/how-the-circulation-adapts-to-valve-disease-aortic-and-mitral-lesions-at-rest-an/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/physiology/how-the-circulation-adapts-to-valve-disease-aortic-and-mitral-lesions-at-rest-an/