Patent Ductus Arteriosus (PDA) Occlusion
In 1966, Porstmann successfully performed the first transcatheter closure of PDA, pioneering interventional treatment for congenital heart diseases. Today, PDA occlusion has become the primary treatment for PDA, with umbrella occluder being the most used device.
Indications
Most cases of PDA can be treated with transcatheter occlusion. Different occluders can be selected based on patient age and PDA type.
Contraindications
Contraindications include:
- Infective endocarditis or vegetations on heart valves or the ductus
- Severe pulmonary hypertension with right-to-left shunting and total pulmonary resistance > 14 Wood units
- PDA-dependent conditions for survival
- PDA associated with other cardiac defects requiring surgical intervention
- Other conditions unsuitable for surgical or interventional treatment
Complications
Complications include:
- Device dislodgement (occurrence rate: 0.3%)
- Hemolysis (occurrence rate: <0.8%)
- Residual shunting and device migration
- Vascular complications and postoperative arrhythmias
Efficacy and Prognosis
The success rate of PDA occlusion is as high as 98%, with very few cases of failure.
Atrial Septal Defect (ASD) Occlusion
In 1976, the first successful closure of an ASD using a double-umbrella occluder was reported. With advancements in devices and imaging techniques, this procedure has become increasingly refined.
Indications
Indications include:
- Secundum ASD with a diameter ≥ 5 mm, right heart volume overload, and left-to-right shunting ≤ 36 mm
- The defect margin≥ 5 mm from the coronary sinus, superior/inferior vena cava, and pulmonary veins, and ≥ 7 mm from the atrioventricular valves
- The atrial septum diameter exceeding the left atrial disc diameter of the chosen occluder
- No associated cardiac anomalies requiring surgical correction
Contraindications
Contraindications include:
- Primum ASD or sinus venosus ASD
- Right-to-left shunting
- Recent infections, hemorrhagic disorders, or thrombi in the left atrium or left atrial appendage
Complications
Complications include:
- Immediate residual shunting occurring in 6-40% of cases, decreasing to 4-12% within 72 hours, and further reducing to 0.1-5% in 3 months
- Thrombus or air embolism
- Vascular complications and infections
- Arrhythmias
Efficacy and Prognosis
For appropriately selected ASDs, the success rate of transcatheter occlusion can reach 100%.
Ventricular Septal Defect (VSD) Occlusion
In 1988, Lock et al. successfully performed transcatheter closure of a VSD using a double-umbrella occluder. With increased experience and improved devices, the indications for VSD occlusion have expanded, and success rates have significantly improved.
Indications
Indications include:
- Isolated VSD with hemodynamic abnormalities, diameter > 3 mm and < 14 mm
- Superior margin of the VSD ≥ 2 mm from the right coronary cusp of the aortic valve, without cusp prolapse or aortic regurgitation
- Echocardiographic visualization of the defect in the short-axis five-chamber view (9-12 o’clock position)
- Muscular VSD > 3 mm
- Residual shunting after surgical repair
Contraindications
Contraindications include:
- Large VSDs or defects in unfavorable anatomical locations where occluders may impair aortic or atrioventricular valve function
- Severe pulmonary hypertension with bidirectional shunting
- Coexisting hemorrhagic disorders, infections, or organ dysfunction (heart, liver, kidney) with embolic risk
Complications
Complications are similar to those of ASD occlusion.
Efficacy and Prognosis
The overall success rate for perimembranous VSD occlusion exceeds 95%. Severe complications occur in 2.61% of cases, with a mortality rate of 0.05%.
Patent Foramen Ovale (PFO) Occlusion
In 2017, multiple authoritative studies confirmed that PFO occlusion is superior to medical therapy for cryptogenic stroke patients with PFO.
Indications
Indications include:
- Patients aged 16-60 years with thromboembolic ischemic stroke and PFO, without other identified stroke mechanisms
- PFO with atrial septal aneurysm (ASA), moderate-to-large right-to-left shunting (RLS), or a diameter ≥ 2 mm
Contraindications
Contraindications include:
- Identifiable causes of embolic stroke
- Acute phase of stroke
- Intracardiac thrombus, complete occlusion of the inferior vena cava or pelvic veins
- Pulmonary hypertension or PFO as a special conduit
- Hemorrhagic disorders or bleeding tendencies
- Systemic or localized infections
Complications
Rare complications include cardiac tamponade, atrial fibrillation, and pulmonary embolism.
Efficacy and Prognosis
Compared to medical therapy, PFO occlusion has been proven effective for secondary stroke prevention, reducing recurrence rates, and alleviating migraine with aura.
Coronary Artery Fistula (CAF) Occlusion
In 1983, Reidy et al. first reported transcatheter closure of a coronary artery fistula. Currently, occlusion devices include coils, PDA occluders, and VSD occluders.
Indications
Indications include:
- Congenital CAF requiring surgical correction without other cardiac anomalies needing surgery
- Clearly visualized fistulas accessible for safe occlusion
- Non-multiple CAF openings
- Fistulas with narrow openings or aneurysmal dilation
Contraindications
Contraindications include:
- Distal coronary branches arising from the fistula
- Severely tortuous coronary vessels involved in the fistula
- Right-to-left shunting or severe pulmonary hypertension
- Severe infections within 1 month before the procedure
Complications
Complications include:
- Occluder dislodgement causing embolism
- Acute myocardial infarction
- CAF dissection
- Transient arrhythmias
Efficacy and Prognosis
Transcatheter occlusion is the preferred treatment for CAF. However, long-term follow-up is essential due to risks of recanalization, coronary dilation, thrombosis, calcification, and myocardial ischemia.
Ruptured Sinus of Valsalva Aneurysm (RSVA) Occlusion
Since Cullen et al. first successfully performed RSVA occlusion in 1994, this technique has become a viable treatment option for patients with clear indications. Currently, PDA or VSD occluders are commonly used due to the lack of dedicated devices.
Indications
Indications include:
- Age > 3 years and weight > 15 kg
- RSVA rupture diameter between 2-12 mm, with ≥ 7 mm from the rupture margin to the aortic valve annulus and ≥ 5 mm from the right coronary artery origin
- Left-to-right shunting from the rupture into the right ventricle or right atrium
- Tolerable cardiac function without associated anomalies requiring surgical correction
Contraindications
Contraindications include:
- RSVA rupture into the left atrium or left ventricle
- Severe pulmonary hypertension with right-to-left shunting
- Severe aortic regurgitation
- Intracardiac thrombus or vegetations
- Infections, hemorrhagic disorders, or severe organ dysfunction
- Associated complex congenital anomalies requiring surgery
Complications
Complications include:
- Residual shunting
- Aortic regurgitation or worsening of existing regurgitation
- Acute left heart failure
- Occluder-related complications (malposition, dislodgement, or coronary obstruction)
Infective endocarditis, arrhythmias, pericardial effusion, and thromboembolic events
Efficacy and Prognosis
RSVA patients often have impaired cardiac function. With appropriate patient selection, transcatheter occlusion has proven effective.