PULMONARY EMBOLISM
Home > Services > Pulmonary Embolism
A Pulmonary Embolism (PE) is a sudden, life-threatening blockage in one of the pulmonary arteries in your lungs. In most cases, a PE is caused by a blood clot that originally formed in the deep veins of the legs (a Deep Vein Thrombosis, or DVT), broke loose, and traveled through the bloodstream, eventually lodging in the lungs. This blockage instantly restricts oxygen-rich blood from reaching the rest of the body and places a massive, dangerous strain on the right side of the heart as it struggles to pump blood past the clot. While standard cases are treated with blood thinners, a severe PE is a critical cardiovascular emergency that requires immediate, advanced catheter-based interventions to rapidly clear the blockage, restore normal blood flow, and prevent fatal heart failure.
1. Indications:
While standard blood thinners (anticoagulants) prevent new clots from forming, interventional procedures are required to actively remove or dissolve massive clots that immediately threaten the patient’s life. Common indications for advanced intervention include:
- Massive PE: A critical emergency where the clot is so large it causes dangerously low blood pressure (shock) and severe strain on the heart, requiring immediate, life-saving clot removal.
- Submassive (Intermediate-Risk) PE: The blood pressure is stable, but an echocardiogram or CT scan shows the right side of the heart is enlarging or failing due to the pressure of pumping against the clot.
- Severe Symptoms: Extreme shortness of breath, severe chest pain, or low oxygen levels that do not improve with initial medical therapy.
- Failure of Anticoagulation: The clot continues to grow or the patient’s condition worsens despite being on high-dose blood-thinning medications.
- Contraindications to Systemic Thrombolytics: Patients who have a massive clot but cannot safely receive traditional IV “clot-busting” drugs because of a high risk of catastrophic bleeding (such as a recent surgery, trauma, or previous stroke).
2. Procedure:
Interventional treatments for a severe Pulmonary Embolism are performed urgently in a specialized cardiac cath lab or interventional radiology suite.
A small puncture is made in a major vein, usually in the groin (femoral vein) or sometimes the neck (jugular vein). Through this access point, a thin, flexible catheter is gently navigated up through the right side of the heart and directly into the blocked pulmonary artery using continuous X-ray imaging (fluoroscopy).
To rapidly clear the lungs, an interventional specialist will typically use one of two advanced techniques:
- Catheter-Directed Thrombolysis (CDT): A specialized catheter with microscopic holes is embedded inside the clot. A powerful clot-busting medication (like tPA) is continuously dripped directly into the blockage at a much lower, safer dose than an IV drip, dissolving the clot over 12 to 24 hours. Some modern catheters also use ultrasonic waves to help drive the medication deeper into the clot (ultrasound-assisted thrombolysis).
- Aspiration / Mechanical Thrombectomy: For patients who cannot receive any clot-busting drugs or need instant relief, the doctor uses a large-bore vacuum catheter to physically suck out or grind up the massive clot, instantly restoring blood flow and relieving the strain on the heart within minutes.
- Note: If the patient has remaining blood clots in their legs and cannot take blood thinners, the doctor may also implant an Inferior Vena Cava (IVC) filter to catch any future clots before they can reach the lungs.
3. Safety:
Catheter-based therapies for Pulmonary Embolism are life-saving procedures that rapidly reverse heart strain and prevent death. They are far less invasive than a traditional open-chest surgical clot removal (surgical pulmonary embolectomy).
Because the patient is inherently critically ill, they are closely monitored in an Intensive Care Unit (ICU) before, during, and after the procedure. Possible risks include:
- Bleeding: The primary risk, especially when clot-busting medications are used. Bleeding can occur at the catheter insertion site or internally. Mechanical vacuum thrombectomy significantly reduces this bleeding risk.
- Arrhythmias: Temporary, irregular heartbeats can occur as the catheter passes through the sensitive right chambers of the heart.
- Vascular Injury: A rare risk of injuring the delicate pulmonary artery or the heart valves with the catheter or suction devices.
- Worsening Right Heart Failure: If the clot cannot be removed quickly enough, the strain on the heart can become irreversible.
- Kidney Strain: A temporary decline in kidney function due to the contrast dye used for X-ray mapping.