Right heart failure medical therapy

Right heart failure Microchapters
Home
Patient Information
Overview
Classification
Pathophysiology
Causes
Differentiating Right heart failure from other Diseases
Epidemiology and Demographics
Risk Factors
Natural History, Complications and Prognosis
Diagnosis
History and Symptoms
Physical Examination
Laboratory Findings
Electrocardiogram
Chest X Ray
CT
MRI
Echocardiography
Treatment
Medical Therapy
Surgery
Primary Prevention
Secondary Prevention
Cost-Effectiveness of Therapy
Future or Investigational Therapies
Case Studies
Case #1
Right heart failure medical therapy On the Web
Most recent articles
Most cited articles
Review articles
CME Programs
Powerpoint slides
Google Images
American Roentgen Ray Society Images of Right heart failure medical therapy All Images X-rays Echo & Ultrasound CT Images MRI
Ongoing Trials at Clinical Trials.gov
US National Guidelines Clearinghouse
NICE Guidance
FDA on Right heart failure medical therapy
CDC on Right heart failure medical therapy
Right heart failure medical therapy in the news
Blogs on Right heart failure medical therapy
Directions to Hospitals Treating Right heart failure
Risk calculators and risk factors for Right heart failure medical therapy

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Currently, the basis of therapy for RHF is most importantly cautious diuresis, sinus rhythm maintenance and management of the underlying cause whenever feasible. Management of RHF, which is largely empiric, can be tailored for etiology specific therapy such as anticoagulation in the case of a pulmonary embolism or antibiotics in the case of endocarditis. Management also comprises of optimizing right ventricular preload, afterload and contractility. Since atrial fibrillation and high grade AV block cause detrimental hemodynamic instability in the setting of a right heart failure in particular, maintaining sinus rhythm and AV synchrony is important .

Medical Therapy

General Measures

• Diuretics
• Nitrates
• Oxygen in some conditions

Management of Acute Right Heart Failure

Preload Optimization:

• In case of hypovolemia, 300-600cc normal saline boluses can be given but to be stopped if the patient is not responsive
• In case of hypervolemia, progressive diuresis can be started with a goal of 500cc daily negative balance.
• If the patient is still hemodynamically unstable following preload optimization, dobutamine is commonly used as a pressor, however if the patient remains refractory to that, then surgical interventions including transplantation and assist devices should be considered.

Afterload optimization:

• iNO, intravenous or inhaled epoprostenol with inotropic support are commonly used in a setting of PAH.
• Cardioversion and pacemaker insertion are the first line therapies for tachyarrythmias and high grade AV block in the setting of an acute right heart failure .

Treatment of Specific Underlying Conditions

Right Ventricular Myocardial Infarction

• In patients presenting with right ventricle myocardial infarction, recent studies have shown that reperfusion therapy via percutaneous catheter intervention reduces the incidence of developing a complete heart block and improves right ventricular ejection fraction. In addition, recovery occurred in a considerable amount of survivors of right ventricular myocardial infarction without acute reperfusion intervention, reiterating the significance of myocardial stunning in right ventricular function function .

Pulmonary Embolism

In pulmonary embolism, thrombolysis (enzymatic dissolution of the blood clot) is advocated if there is dysfunction of the right ventricle.

Chronic Obstructive Pulmonary Disease

In Chronic Obstructive Pulmonary Disease (COPD), long-term oxygen therapy may improve cor pulmonale.

Pulmonary Arterial Hypertension

• Treatment is determined by whether the PH is arterial, venous, hypoxic, thromboembolic, or miscellaneous. Since pulmonary venous hypertension is synonymous with congestive heart failure, the treatment is to optimize left ventricular function by the use of diuretics, beta blockers, ACE inhibitors, etc., or to repair/replace the mitral valve or aortic valve.
• In PAH, lifestyle changes, digoxin, diuretics, oral anticoagulants, and oxygen therapy are considered conventional therapy, but have never been proven to be beneficial in a randomized, prospective manner.
• The combination of '''dobutamine''' (2 to 5 μg/kg.min ) and NO in the setting of right heart failure secondarily to pulmonary hypertension have been shown to be beneficial in increasing the cardiac output and decreasing the pulmonary vascular resistance. As for Digoxin therapy, it has been studied in patients with pulmonary hypertension and chronic pulmonary disease, where it was shown to improve CO by about 10% in an acute setting of right heart failure, but no studies have supported its use for a long term .
• High dose calcium channel blockers are useful in only 5% of IPAH patients who are vasoreactive by Swan-Ganz catheter. Unfortunately, calcium channel blockers have been largely misused, being prescribed to many patients with non-vasoreactive PAH, leading to excess morbidity and mortality.

Vasoactive substances

Three major pathways are involved in the abnormal proliferation and contraction of the smooth-muscle cells of the pulmonary artery in patients with pulmonary arterial hypertension. These pathways correspond to important therapeutic targets in this condition and play a role in determining which of three classes of drugs — endothelin receptor antagonists, phosphodiesterase type 5 inhibitors, and prostacyclin derivatives — will be used.

Prostaglandins

Prostacyclin (prostaglandin I₂) is commonly considered the most effective treatment for PAH. Epoprostenol (synthetic prostacyclin, marketed as Flolan®) is given via continuous infusion that requires a semi-permanent central venous catheter. This delivery system can cause sepsis and thrombosis. Flolan® is unstable, and therefore has to be kept on ice during administration. Since it has a half-life of 3 to 5 minutes, the infusion has to be continuous (24/7), and interruption can be fatal. Other prostanoids have therefore been developed. Treprostinil (Remodulin®) can be given intravenously or subcutaneously, but the subcutaneous form can be very painful. Iloprost (Ilomedin®) is also used in Europe intravenously and has a longer half life. Iloprost (marketed as Ventavis®) is the only inhaled form of prostacyclin approved for use in the US and Europe. This form of administration has the advantage of selective deposition in the lungs with less systemic side effects.

Endothelin receptor antagonists

The dual (ET and ET) endothelin receptor antagonist bosentan (marketed as Tracleer®) was approved in 2001. Approved in June 2007, ambrisentan is marketed as Letairis® in U.S. by Gilead Sciences., a selective endothelin receptor antagonist that blocks only the action of ET, has been approved for use in Canada and the European Union, to be marketed under the name Thelin®. Sitaxsentan has not been approved for marketing by the US FDA. A new trial is being planned to address FDA's concerns.

Phosphodiesterase type 5 inhibitors

Sildenafil, a selective inhibitor of cGMP specific phosphodiesterase type 5 (PDE5), was approved for the treatment of PAH in 2005. It is marketed for PAH as Revatio®. Tadalafil (currently marketed as Cialis® for erectile dysfunction) is currently is Phase III clinical trials.

Other agents

Vasoactive intestinal peptide by inhalation should enter clinical trials for PAH in 2007. PRX-08066 is a serotonin antagonist currently being developed for hypoxic pulmonary hypertension.