Bubble Test: Tracking "Bubbles" in the Heart

01 Bubble Test: Tracking "Bubbles" in the Heart

The Bubble Test, formally called Contrast-Enhanced Transcranial Doppler (C-TCD), involves injecting a saline solution containing microbubbles into a patient’s cubital vein. The patient is instructed to hold their breath or cough while a TCD emboli detection system monitors the movement of these microbubbles. Normally, bubbles are absorbed in the pulmonary circulation, and no microemboli are detected. However, if a patent foramen ovale (PFO) exists, bubbles bypass the lungs, traveling from the right atrium to the left atrium and into cerebral circulation. Ultrasound captures these signals.

Principle: Saline is agitated to create microbubbles → Injected intravenously → Ultrasound tracks bubble pathways.

Key Objective: Detect right-to-left cardiac shunts (e.g., PFO). Such shunts may allow venous clots or gas to bypass the lungs, increasing risks of stroke or migraines. TCD’s high sensitivity, non-invasive nature, and repeatability make it a gold standard for shunt screening, aiding precise diagnosis and personalized treatment.

02 Who Needs a Bubble Test?

Unexplained stroke/transient ischemic attack (TIA) (especially in young patients)

Refractory migraines (particularly with aura)

Unexplained syncope or dizziness (to rule out cardiac abnormalities)

Divers/astronauts (assessing decompression sickness risk)

Routine PFO screening

Post-PFO closure follow-up

03 Contraindications

Severe cardiac, pulmonary, hepatic, or renal dysfunction.

Severe cyanosis with large intracardiac shunts, severe pulmonary hypertension, advanced emphysema, or coronary syndrome.

Recent abdominal surgery or pregnancy.

Children under 3 years old.

04 Procedure

Safe and painless, completed in 10 minutes:

1、Patient lies supine for 1 minute.

2、Dual-channel/depth TCD monitoring detects bilateral middle cerebral artery (MCA) flow signals (40-65 mm depth). Adjust settings for optimal signal clarity.

3、Establish cubital venous access with a Y-type catheter. Prepare agitated saline (rapidly inject 20 times between syringes).

4、Rapidly inject the agitated saline as a bolus (3-5 seconds) while starting a timer.

5、Observe and record blood flow/embolic signals for 20 seconds.

6、Patient rests for 2 minutes.

7、Repeat steps 4-5.

8、Reinject agitated saline and instruct the patient to perform a Valsalva maneuver 5 seconds post-injection.

9、Monitor and record signals for 25 seconds.

10、Patient rests for 2 minutes.

11、Repeat steps 8-9.

Notes:

No fasting required; avoid strenuous exercise beforehand.

Apply pressure to the injection site for 3-5 minutes post-test. Minor dizziness may occur but resolves with rest.

05 Results: Is Your Heart "Leaking"?

Negative (Normal): Bubbles confined to the right heart; no abnormal pathways.

Positive (Abnormal): Bubbles detected in the left heart, indicating right-to-left shunt (e.g., PFO, pulmonary arteriovenous fistula).

Diagnostic Grading (4-level scale):

No shunt: 0 microbubbles

Minor shunt: 1-10 microbubbles

Moderate shunt: 11-25 microbubbles

Large shunt: >25 microbubbles (>60 or "shower/curtain" patterns indicate severe shunting).

Follow-up: Positive results warrant transesophageal echocardiography (TEE) or cardiac CT to quantify shunts. Treatment (e.g., closure) depends on symptoms and shunt severity.

06 FAQs

Q: Is the Bubble Test risky?

A: Microbubbles are non-toxic and harmless. The test is extremely safe.

Q: Does every PFO require treatment?

A: Not necessarily. Asymptomatic small shunts may only need monitoring.

Final Note:

A "tiny hole" in the heart could be a major health threat! If you or family members suffer unexplained headaches or stroke-like symptoms, consult a cardiologist about the Bubble Test. Share this knowledge—empower others to safeguard their health!

Pricing: 158 RMB/person

Transcranial Color Doppler Ultrasound: 56 RMB

Ultrasound-Guided Clinical Procedure: 102 RMB

100ml saline (self-provided)

Locations:

Central Campus: Room 428, Cardiocerebral Function Examination Dept., 4F Outpatient Building, Wuwei Tumor Hospital.

Tel: 0935-6988551

Heavy Ion Campus: Room E303, 3F Outpatient Building, Wuwei Tumor Hospital.

Tel: 0935-6989085