Skip to Main Content

++

  • Right heart syndromes (RHS) as a cause of shock are less common than left heart dysfunction, but recognizing them requires a high level of vigilance.
  • Clues to recognizing RHS as a cause of shock include a history of a condition that is associated with pulmonary hypertension, elevated neck veins, peripheral edema greater than pulmonary edema, or a right-sided third heart sound, in addition to electrocardiographic, radiographic, and echocardiographic findings.
  • Echocardiography is extremely valuable, not only for demonstrating the presence of RHS, but also for guiding hemodynamic management.
  • Progressive right heart shock can be worsened by excessive fluid infusion, concomitant left ventricular failure, inappropriate application of extrinsic positive end-expiratory pressure (PEEP) and hypoxia.
  • The drug of choice for resuscitation of patients with acute RHS is dobutamine, initially infused at 5 μg/kg per minute. Systemically-active vasoconstrictors may provide additional benefit.
  • Prostacyclin and nitric oxide are often beneficial in improving pulmonary hemodynamics and oxygenation, but may not improve survival.

++

In the majority of patients with shock due to “pump failure,” assessment is focused appropriately on the left ventricle. However, in a substantial minority of patients, right heart dysfunction is the cause of shock. Examples include acute pulmonary embolism (PE), other causes of acute right heart pressure overload (e.g., acute respiratory distress syndrome [ARDS] treated with positive pressure ventilation), acute deterioration in patients with chronic pulmonary hypertension, and right ventricular infarction. Although right ventricular infarction differs from the other right heart syndromes (RHS) in that the pulmonary artery pressure is not high, in many other regards right ventricular infarction resembles the other syndromes, so we will consider them together. Failure to consider the right heart in the differential diagnosis of shock risks incomplete or inappropriate treatment of the shock. It would be hard to overemphasize the importance of echocardiography, both in aiding the recognition of the right heart syndromes and in guiding management. In this chapter we review the notable features that distinguish the right heart from the left, describe the themes that unify the acute RHS and allow their recognition, discuss the pathophysiology and differential diagnosis of RHS, and review their management.

++

The right ventricle (RV) has long been considered the “forgotten ventricle,” because under normal pressure and volume loading conditions the RV is thought to function as a passive conduit for systemic venous return. When the pulmonary vasculature is normal, right ventricular performance has little impact on the maintenance of cardiac output. In animal models, complete ablation of the right ventricular free wall has little effect on venous pressures.

++

Despite the requirement for an equal, average cardiac output between the left and right ventricles, the bioenergetic requirement for RV ejection is approximately one fifth of the left ventricle (LV). This is in large part accounted for by the significant difference in downstream vascular resistance between the systemic and pulmonary circulations. In comparison with the LV, the RV ejects into a low-resistance circuit (normally only one tenth the resistance of the ...

Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.

Ok

About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessAnesthesiology Full Site: One-Year Subscription

Connect to the full suite of AccessAnesthesiology content and resources including procedural videos, interactive self-assessment, real-life cases, 20+ textbooks, and more

$995 USD
Buy Now

Pay Per View: Timed Access to all of AccessAnesthesiology

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.