Pulmonary Artery Catheterization - Indications, Contraindications, Technique, and Complications

Introduction

The human heart is a complex and critical organ in the human body. Any irregularity or abnormality in its function can pose grave challenges to one’s life. Numerous diagnostic interventions are in practice for assessing cardiac functions and detecting abnormalities. Cardiac catheterization is one such diagnostic procedure that can sometimes be employed for treating certain heart conditions.

Through cardiac catheterization, various functional parameters of the heart can be accurately measured, which provides crucial information regarding the functional status of the heart. This procedure is done with the help of a specialized tube, which is medically coined as a catheter. It is a specially designed tube with greater flexibility and a smaller diameter. This catheter is then introduced into the appropriate blood vessel to gain access to the heart. Cardiac catheterization procedures are broadly categorized into two groups based on the side of the heart that will be studied and assessed. Right and left cardiac catheterization are concerned with the right and left side of the heart, respectively.

What Is Pulmonary Artery Catheterization?

Pulmonary artery catheterization (PAC) is a form of cardiac catheterization where the catheter is introduced and advanced through an appropriate blood vessel to approach the right side of the heart and pulmonary artery. Pulmonary arteries are those concerned with transporting oxygen-deficient blood that reaches the right side of the heart from different areas of the body to the lungs. In the lungs, the blood gets loaded with oxygen molecules and drives out the carbon dioxide molecules from the blood. The synonym right cardiac catheterization procedure widely known as PAC, as it concerns the heart’s right side. The catheter employed for pulmonary artery catheterization procedure is typically known as a pulmonary artery catheter. It not only guides in diagnosis, in addition it can be used as a treatment strategy for certain cardiac conditions.

What Are the Indications for Pulmonary Artery Catheterization?

There is a wide range of cardiac conditions for which pulmonary artery catheterization is proven fruitful for diagnosis and treatment. Some of the conditions for which pulmonary artery catheterization is routinely employed include the following:

• Assessment of Shock: Shock is a grave and emergency condition with an abrupt blood flow check. Pulmonary artery catheterization aids in identifying the etiology behind the shock development and facilitates timely treatment.

• Pulmonary Hypertension: PAC helps in diagnosing pulmonary hypertension. It is a medical condition marked by boosted lung blood pressure. PAC gauges and assesses the blood pressure in the pulmonary artery and, in that way, helps detect pulmonary hypertension.

• Heart Failure: In heart failure, the heart fails to drive out adequate blood to keep the normal functions in the body. Pulmonary artery catheterization gives an idea about the extent of blood flow depreciation and pressure within the heart compartments (chambers). In addition, it is also employed as part of the treatment for complex heart failure conditions.

• Pericardial Disease Assessment: Pulmonary artery catheterization aids in assessing the diseases that mainly affect the outer heart covering.

• Right-Sided Valvular Disease: Abnormalities in the heart valves, specifically in the right half of the heart, can be promptly assessed and evaluated with the help of the pulmonary artery catheterization technique.

• Congenital Heart Disease: Inborn error in the heart concerning the right side is often assessed with the help of PAC. It provides a better understanding of the extent of the defect.

What Is the Technique Involved in Pulmonary Artery Catheterization?

The technique and procedure involved in pulmonary artery catheterization are similar to cardiac catheterization. Routinely the central veins in the neck, arm, groin, or collarbone are selected for catheter insertion. The catheter is then advanced to the upper right compartment of the heart (right atrium) and the corresponding lower compartment (right ventricle) through the valvular connection. The catheter is finally guided into the pulmonary artery. This catheter advancement is assisted with the help of certain imaging techniques to confirm that the catheter is moving in the right direction without inducing any trauma to the blood vessel and to the heart.

The catheter is specially designed with a ballooning tip, which can be blown up once the catheter approaches the pulmonary artery. This inflation and deflation enable the assessment of various cardiac functional parameters like right atrial pressure, oxygen saturation in the blood, pulmonary artery pressure, central vein pressure, patency in the blood flow, right ventricular pressure, and many more. A right heart catheter or Swan-Ganz catheter is used for pulmonary artery catheterization.

What Are the Contraindications for Pulmonary Artery Catheterization?

There are certain conditions under which pulmonary artery catheterization cannot be performed safely. A few of the potential contraindications for this invasive procedure include the following:

• The presence of infection at the insertion point of the catheter is an absolute contraindication for pulmonary artery catheterization, as it carries the risk of extension of the infection into the internal organs.

• If the patient has a ventricular assist device (VAD) implanted in the right lower heart chamber, then PAC cannot be performed in such patients.

• Upon pulmonary artery catheterization, patients with bundle branch block (impaired impulse conduction) on the left side are more susceptible to developing bundle branch block on the right side. Hence, the procedure should be performed under extreme caution in such patients, as it is considered a relative contraindication.

Are There Any Risks Associated With Pulmonary Artery Catheterization?

Though pulmonary artery catheterization is invasive, it is quite a safe procedure. However, at times, it poses certain risks and challenges:

• Insertion point infection.

• Break in the vessel wall.

• Air embolism (air bubble trapped within the blood vessel).

• Arrhythmias (loss of heartbeat rhythm).

• Trauma to the heart wall or valves.

• Catheter misplacement.

• Pulmonary infarction (impaired blood flow to lung segment).

• Thromboembolism (blood clot formed within the vessel in response to trauma to the blood vessel).

Conclusion

Pulmonary artery catheterization is a routinely advised diagnostic technique that helps assess various cardiac functions and parameters. The application of PAC is not limited to diagnosis. On the contrary, it is extended to various therapeutic purposes. A catheter tube is advanced from one of the central veins to the pulmonary artery with the help of imaging techniques. Patients with pulmonary hypertension benefit the most from pulmonary artery catheterization as it helps disclose the etiology behind the condition. Prompt adherence to follow-up visits and post-procedural instructions given by the doctors helps in the fast healing of the incision wound created at the insertion point. Trained and qualified specialist doctors carry out the procedure without giving room for potential complications.