Chronic thromboembolic pulmonary hypertension (CTEPH) occurs when pulmonary emboli (PE) do not resolve and remain as scar-like chronic PE. Among the types of pulmonary hypertension (PH), CTEPH has unique diagnostic features and therapeutic options. It’s also the only PH type potentially curable with surgery.

Stanford Health Care’s multidisciplinary CTEPH clinic provides high-level care to patients with this complex disease. The clinic brings together experts from pulmonary and cardiovascular medicine, including:

• Pulmonologists with expertise in PH and CTEPH
• Cardiothoracic surgeons
• Cardiovascular anesthesiologists
• Cardiovascular critical care medicine specialists
• Interventional cardiologists
• Thoracic/cardiovascular radiologists
  

“We developed the CTEPH clinic to ensure a coordinated approach,” says pulmonologist Yon Sung, MD. “Our focus is providing an accurate diagnosis and developing a personalized treatment plan that, whenever possible, includes surgery.”

Diagnosing CTEPH: A Challenge for Pulmonologists and Cardiologists
Delayed diagnosis and misdiagnosis are common in patients with CTEPH. According to Dr. Sung, there are several reasons for this:

• CTEPH often occurs after a pulmonary embolism (PE), but approximately 25% of patients do not have a known history of PE.
• After a PE, CTEPH may have a long silent period before symptoms begin.
• Symptoms are often nonspecific (shortness of breath, edema, fatigue, chest pain, and lightheadedness).

Selecting the right tests is important. Accurate diagnosis typically requires several tests to establish the characteristic features of CTEPH, including:

• Ventilation/perfusion scan (V/Q) scan: Screens for CTEPH based on the profile of perfusion abnormalities
• Transthoracic echocardiography: Screens for PH
• CT pulmonary angiography: Detects clots in the pulmonary arteries, although identifying chronic clots found in CTEPH can be challenging
• Right heart catheterization: Confirms the diagnosis of PH
• Pulmonary angiogram: Further characterizes the location and features of chronic clots

“Pulmonologists and cardiologists should have a high index of suspicion for CTEPH in patients with a history of PE or chronic cardiopulmonary symptoms,” says Dr. Sung. “When in doubt, referral to a specialized center can help ensure patients get the right diagnosis and treatment.”

Treating — and Potentially Curing — CTEPH
At Stanford Health Care, the multidisciplinary team reviews individual cases to make a correct diagnosis and develop a treatment plan. For eligible patients, pulmonary thromboendarterectomy (PTE) is the recommended treatment for CTEPH. “Many patients are unaware PTE is the treatment of choice and can cure CTEPH, although the disease can recur,” says Dr. Sung.
 
PTE is a complex, open-chest surgery offered only at select medical centers nationwide. It involves placing the patient on cardiopulmonary bypass and cooling the patient to 20°C to protect vital organs. For 20 minutes at a time, the patient undergoes circulatory arrest to stop blood flow, which creates a bloodless field and allows the surgeon to resect the clots.

The main criteria for PTE eligibility include:

• Clot location: Clots should be in the larger pulmonary arteries that are accessible to the surgeon.
• Patient health: Patients must be healthy enough to undergo this intensive surgery. Some relevant factors include patient age, coexisting health conditions, and heart and lung function.

For patients who are not eligible for PTE, balloon pulmonary angioplasty (BPA) may be an option. BPA involves inserting a catheter through the femoral vein. The physician guides the catheter to the obstructed vessels and inflates a balloon to open the artery.

All patients with CTEPH should be on chronic anticoagulant therapy. Other medications, particularly pulmonary vasodilators, are also an important part of CTEPH care — alone or in combination with PTE or BPA. Riociguat is the only FDA-approved medication for CTEPH. It improves blood flow by vasodilating the pulmonary arterioles. PH specialists also use a wide range of other pulmonary vasodilators off-label to improve CTEPH symptoms.

Why Refer Patients to Stanford Health Care for CTEPH Care
Stanford Health Care is an international leader in PH. In 1981, a Stanford surgeon performed the world’s first heart-lung transplant in a patient with PH. Stanford was also one of the first Comprehensive Care Centers accredited by the Pulmonary Hypertension Association in 2014.

“Our PH and CTEPH specialists are a valuable resource for pulmonologists and cardiologists,” says Dr. Sung. “We work with clinicians across northern California to provide consultations on diagnosis and treatment.”

Stanford Health Care also provides comprehensive services to refer and track patients, as well as the latest information and news for physicians and office staff.