VALSALVA MANEUVER: CARDIAC & NON-CARDIAC USES
Phase 1. The onset of blowing. The pressure within the chest and abdomen increases and presses upon the arteries in the chest, which results in an increase of mean arterial blood pressure. This activates the baroreceptor reflex, which results in an increase of parasympathetic (vagal) activity and hence in a drop of heart rate. The increased intrathoracic pressure also reduces the amount of blood that comes into the right atrium (decreased venous return or preload).
Phase 2. A decrease of venous return results in a lower amount of blood that is ejected from the heart, which results in a decrease of central venous pressure and consequently in a decrease of mean arterial blood pressure. This activates the baroreflex, which results in a decrease of the parasympathetic (vagal) activity and consequent increase of the heart rate, and in an increase of sympathetic activity, which constrict the arteries (an increase of peripheral resistance), which results in a slight raise of the blood pressure at the end of phase 2 (2b).
Phase 3. Relaxation – the end of the maneuver. The intrathoracic pressure decreases, so the intrathoracic arteries widen, which results in a brief drop of the blood pressure. At the same time, the venous blood fills the heart.
Phase 4. The heart ejects the blood into the arterial system against increased peripheral resistance (which has developed in the phase 2), so the blood pressure raises again (blood pressure overshoot). This activates the baroreflex, which results in a drop of heart rate (bradycardia). Eventually, both the blood pressure and heart rate normalize.
Valsalva Maneuver in cardiology
The Valsalva maneuver works by decreasing preload to the heart. A complementary maneuver for differentiating disorders is the handgrip maneuver, which increases afterload.
The Valsalva maneuver (in the straining phase) reduces the filling of the right and then the left side of the heart. Stroke volume and blood pressure falls, while the heart rate increases.The Valsalva maneuver may be used to arrest episodes of supraventricular tachycardia.The maneuver can sometimes be used to diagnose heart abnormalities, especially when used in conjunction with echocardiogram. For example, the Valsalva maneuver (phase II) increases the intensity of hypertrophic cardiomyopathy murmurs, namely those of dynamic subvalvular left ventricular outflow obstruction. At the same time, the Valsalva maneuver (phase II) decreases the intensity of most other murmurs, including aortic stenosis and atrial septal defect. During the first few seconds of the Valsalva maneuver (phase I) the opposite findings will be the case.
| Effect of Valsalva (Phase II) | Cardiac finding |
|---|---|
| Decreases murmur | |
| Aortic stenosis | |
| Pulmonic stenosis | |
| Tricuspid regurgitation | |
| Increases murmur | |
| Hypertrophic cardiomyopathy, mitral valve prolapse |
Non-cardiac uses
Valsalva maneuver can be used as a provocative test to check for:
- Inguinal (groin) hernia
- Prolapse of the uterus, bladder or vagina (pelvic floor weakness)
- Varicocele (engorged veins in the scrotum) during ultrasound in a standing position
- Intrinsic sphincter deficiency in stress urinary incontinence
- A pinched nerve in the neck or lumbar spine (cervical or lumbar radiculopathy). The maneuver is positive when it triggers pain in the neck, shoulder, arm or lower back.
- Eustachian tube dysfunction (ETD)
- Neurogenic orthostatic hypotension
- Chiari malformation (a congenital disorder of the cerebellum); the Valsalva maneuver (coughing) triggers headache at the back of the head
- Cerebrospinal fluid (SCF) leak through the nose after long-term repeated use of the Valsalva maneuver
- Abnormal connections between the mouth and maxillary sinuses (oroantral fistulas) after a tooth extraction
- Primary cough headache
- Function of the autonomous nervous system
- An abnormal blood pressure response (for example, an absence of the blood pressure raise in phase 4) suggests an abnormality of the sympathetic system.
- An abnormal heart rate response suggests an abnormality of the parasympathetic system.
Valsalva as a Treatment Aid
Valsalva maneuver can help:
- Equalize the pressure between the middle ear and the ambient pressure (ear clearing) during scuba diving, driving from a steep hill, elevator descending, parachuting or plane landing or in individuals with Eustachian tube dysfunction (ETD)
- Decrease ringing in the ears (tinnitus); it may increase tinnitus in some individuals
- Clear mucus and relieve pain in sinusitis
- Expel pus from a clogged ear in middle ear infection
- Voiding in older men with an enlarged prostate
- Stop hiccups
- Promote swallowing is individuals with difficulty swallowing (dysphagia)
- Push the stool out in individuals with neurogenic bowel due to spinal cord injury
- Interrupt palpitations (supraventricular tachycardia (SVT), including atrial fibrillation); the maneuver alone is effective in only 5-25% cases; it is also somewhat effective in children.
Source: ehealthstar , wiki
