Simultaneously increases venous return to the right heart and increases afterload and peripheral resistance. Augments murmurs of aortic regurgitation, aortic stenosis, mitral regurgitation and diastolic murmur of mitral stenosis.
Increases intrathoracic pressure, which reduces size of left ventricle LV ; decreases venous return to the right heart and subsequently to the left heart.
Common Health Topics. Videos Figures Images Quizzes Symptoms. Maneuvers That Aid in Diagnosis of Murmurs. Causes intense venodilation, which reduces venous return to the right heart. Reduces murmur of hypertrophic obstructive cardiomyopathy and mitral valve prolapse. Augments murmur of hypertrophic obstructive cardiomyopathy and mitral valve prolapse. Reduces murmurs of aortic stenosis, mitral regurgitation, and tricuspid stenosis. Augments murmurs of hypertrophic obstructive cardiomyopathy, aortic stenosis and mitral valve prolapse Reduces murmur of mitral regurgitation.
The key event occurring during the maneuver is increasing intrathoracic pressure leading to the reduction of preload to the heart. The reflex cardiovascular changes during and after the maneuver are because of reduced preload engaging baroreflex and other compensatory reflex mechanisms.
Based on the characteristic hemodynamic changes, the Valsalva maneuver divides into four phases. Phase I, which corresponds to the onset of strain, is associated with a transient rise in blood pressure because of the emptying of some blood from the large veins and pulmonary circulation.
Phase II follows this when positive intrathoracic pressure leads to a reduced venous return to the heart. Because of reduced venous return and thus reduced preload, stroke volume falls; this leads to a fall in blood pressure activating the baroreceptors in the carotid sinus and aortic arch.
The vagal withdrawal followed by increased sympathetic discharge ensues, leading to marked tachycardia, increased cardiac output, and vasoconstriction which leads to the recovery of blood pressure to the normal values in healthy individuals. Phase III is the transient phase involving the release of strain which leads to a sudden dip in blood pressure.
The release of positive pressure leads to expansion of the pulmonary vascular bed and reduces left ventricular cross-sectional area resulting in a transient fall in blood pressure. Phase IV is the overshoot of the blood pressure above the baseline, which is because of the resumption of normal venous return to the heart stimulated by the sympathetic nervous system during Phase II.
The overshoot of blood pressure leads to stimulation of baroreflex leading to bradycardia and return of blood pressure to the baseline. Valsalva maneuver is used for assessment of autonomic function status, as a marker for heart failure, for termination of arrhythmias, murmur differentiation, and various other indications. Valsalva maneuver is relatively safe and can be performed in all patients.
Side effects reported are rare. However, since there is a rise in intraocular and intra-abdominal pressure, therefore the test must be avoided in patients with retinopathy and intraocular lens implantation. Valsalva retinopathy may result in susceptible patients.
Therefore, caution is necessary for patients with pre-existing coronary artery disease, valvular disease or congenital heart disease. Measurement of continuous beat-to-beat blood pressure can help in testing baroreflex sensitivity. The patient can perform the maneuver in the sitting, supine, or recumbent position. Some reports advocate recumbent position, [10] while others report an increased incidence of abnormal blood pressure responses in the supine position.
Lower pressures may not be sufficient while higher pressures suffer from poor reproducibility. Modified VM: In order to increase the relaxation phase venous return and vagal stimulation, a modification to the standard VM has been described in the REVERT trial which includes supine positioning with leg elevation immediately after the Valsalva strain.
This is used for the emergency treatment of supraventricular tachycardias. Reverse VM: The patient in a sitting position is asked to inhale against resistance for ten seconds while keeping the nose pinched and having the mouth closed tightly. This leads to increased vagal tone and decreased sympathetic activity which in turn leads to bradycardia and arterial hypotension the Bezold—Jarich reflex causing supraventricular tachycardia to resolve in the next 15 seconds if effective.
Autonomic function assessment: Valsalva maneuver is an integral part of Ewing battery of tests used for the evaluation of cardiac autonomic neuropathy. Also, determination of baroreflex sensitivity BRS can be performed using the Valsalva maneuver to assess the integrity of the baroreflex by estimating the slope of a regression plot between RR intervals and systolic blood pressure values during phases II and IV of the maneuver.
Assessment of heart failure: VM is useful for the assessment of heart failure. Patients with heart failure show an abnormal blood pressure overshoot in response to the Valsalva maneuver due to impaired ventricular function. Increased vagal activity, leading to increased refractoriness of atrioventricular AV nodal tissue interrupting re-entry, has been proposed as the mechanism for termination of PSVT.
Diagnosis of murmurs: VM may be used to differentiate between different murmurs. Since the maneuver reduces preload and thus end-diastolic volume, it can help accentuate some murmurs while diminishing others. The murmur of aortic stenosis AS is reduced in intensity on the administration of VM because reduced end-diastolic volume EDV diminishes the blood available for ejection through the stenosed aortic orifice.
To detect bleeding points towards the end of thyroid surgery and for the diagnosis of varicocele. To assist in the radiological diagnosis of liver hemangiomas, [14] venous disease, [15] and foramen ovale.
To reduce the venipuncture pain in pregnant women. Valsalva maneuver VM is a simple non-invasive test that can be easily performed using a mouthpiece and a manometer. While the maneuver is relatively safe, it is prudent to rule out any pre-existing disease of the retina before performing the maneuver.
Therefore, one should consult an ophthalmologist and seek a thorough examination of the fundus in patients with suspected retinopathy. Similarly, the opinion of a cardiologist may assist in patients with pre-existing ischemic or valvular heart disease before the performance of VM. It can assist the neurologist to identify patients suffering from autonomic neuropathy.
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