This activity outlines the indications and contraindications for performing the Valsalva maneuver and highlights the role of the interprofessional team in using this test to evaluate for autonomic dysfunction.
Objectives: Describe the Valsalva maneuver. Review how to perform the Valsalva maneuver. Explain the clinical significance of the Valsalva maneuver.
Summarize the clinical impact that autonomic dysfunction can have on patients and how the interprofessional team can best evaluate and treat patients with autonomic dysfunctions to improve patient outcomes.
Valsalva maneuver is the performance of forced expiration against a closed glottis. Many activities of our daily lives such as straining during defecation or playing the saxophone entail the performance of the Valsalva maneuver.
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. 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. Left-sided murmurs usually are louder during expiration. Murmurs caused by blood flow across normal or obstructed valves eg, PS, MS become louder with both isotonic and submaximal isometric handgrip exercise.
How is hypertrophic obstructive cardiomyopathy diagnosed? HCM is diagnosed based on medical history your symptoms and family history , a physical exam, and echocardiogram results. Additional tests may include blood tests, electrocardiogram, chest X-ray, exercise stress test, cardiac catheterization, CT scan, and MRI. What makes hypertrophic cardiomyopathy worse? Having hypertrophic cardiomyopathy means that the heart muscle myocardium can become excessively thick.
The heart muscle can also become scarred. The thickening and scarring of the muscle makes the heart muscle stiff. This makes it harder for the heart to pump blood out of your heart and around your body. Why does Valsalva decrease preload? The increase in intrathoracic pressure that occurs during the Valsalva maneuver incites a sequence of rapid changes in preload and afterload stress.
During the strain, venous return to the heart is decreased and peripheral venous pressures become increased. Which drugs are contraindicated in hypertrophic cardiomyopathy? Agents to reduce pre- or afterload such as nitrate, ACE inhibitors, nifedipine-type calcium antagonists are contraindicated with HOCM due to possible aggravation of the outflow tract obstruction.
What is hypertrophic cardiomyopathy and why is it so dangerous? The thickened heart muscle can make it harder for the heart to pump blood. However, in a small number of people with HCM, the thickened heart muscle can cause shortness of breath, chest pain or problems in the heart's electrical system, resulting in life-threatening abnormal heart rhythms arrhythmias.
Does cardiomyopathy show up on ECG? An EKG can be used to detect cardiomyopathy as well as other problems, including heart attacks, arrhythmias irregular heartbeats and heart failure. How should you determine whether a murmur is systolic or diastolic?
Systolic murmurs occur between the first heart sound S1 and the second heart sound S2.
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