Angioplasty

Angioplasty, also known as balloon angioplasty or percutaneous transluminal angioplasty, is a minimally invasive endovascular procedure used to widen narrowed or obstructed arteries or veins. It is most frequently employed in the treatment of atherosclerosis, a condition characterised by the accumulation of lipid-laden plaques within the vascular wall. The technique involves passing a balloon-tipped catheter through the vascular system to the site of stenosis, inflating the balloon to compress the obstructing material and, where necessary, deploying a stent to maintain long-term vessel patency.

Uses and Indications

Angioplasty now encompasses a wide range of percutaneous vascular interventions and is applied in several clinical contexts.
Coronary angioplastyUsed to treat stenotic lesions within the coronary arteries, coronary angioplasty forms part of percutaneous coronary intervention (PCI). It is indicated in conditions such as unstable angina, non-ST-elevation myocardial infarction (NSTEMI), ST-elevation myocardial infarction (STEMI) and spontaneous coronary artery perforation. By restoring coronary blood flow, PCI alleviates angina, improves functional capacity and enhances quality of life in patients with stable coronary disease.
Peripheral angioplastyPeripheral angioplasty targets stenoses or occlusions of arteries outside the coronary circulation, particularly those supplying the abdomen, kidneys and lower extremities. It is commonly used in the management of peripheral artery disease, often in combination with stents, guidewires and atherectomy devices. For chronic limb-threatening ischaemia, angioplasty can relieve claudication, although long-term results may favour bypass surgery in patients with adequate life expectancy and suitable autogenous veins.
Renal artery angioplastyRenal artery stenosis can contribute to refractory hypertension and loss of renal function. Atherosclerotic stenosis may be treated by angioplasty with or without stenting. Although the evidence for broad use is limited, angioplasty may be considered in individuals with recurrent flash pulmonary oedema or heart failure attributed to renal artery compromise.
Carotid angioplastyCarotid artery angioplasty with stenting serves as an alternative to carotid endarterectomy for individuals at high surgical risk. It is particularly useful for lesions caused by previous radiation therapy or for anatomically complex stenoses not amenable to open surgery.
Venous angioplastyVenous angioplasty is used to treat venous stenosis, including those affecting haemodialysis access circuits. Drug-coated balloon angioplasty has shown improved short-term and mid-term patency compared with conventional balloons. In selected cases, angioplasty may address residual subclavian vein stenosis after thoracic outlet decompression. Deep venous stenting may be employed for chronic obstructive venous disease where appropriate.

Contraindications

The procedure requires a vascular access point, commonly via the femoral or radial arteries or the femoral vein. Angioplasty is contraindicated when no suitable access vessel exists due to small calibre, occlusion, heavy posterior calcification, haematoma or prior surgical bypass in the intended route.
Percutaneous transluminal coronary angioplasty is specifically contraindicated in left main coronary artery disease because of the high risk of vasospasm or sudden closure during the procedure. It is also not recommended when coronary stenosis is less than 70 per cent, as such lesions are unlikely to be haemodynamically significant.

Technique

Angioplasty is typically performed percutaneously using the Seldinger technique to introduce an access sheath into the blood vessel. Fluoroscopic guidance with radiopaque contrast dye enables real-time visualisation of guidewires and catheters.
A tapered guidewire is first passed through the stenosis. Depending on vessel tortuosity and lesion hardness, intermediate or stiff guidewires may be selected. A balloon catheter is then advanced over the wire to the target site. Once correctly positioned, the balloon is inflated to pressures of 6–20 atmospheres to expand the narrowed vessel. Stents may be inserted to reduce the risk of restenosis.
After treatment, all devices are withdrawn and the access site is closed using manual pressure or a vascular closure device. For coronary interventions, transradial access is preferred for acute coronary syndromes due to its lower rates of bleeding, vascular complications and mortality compared with transfemoral access.

Risks and Complications

Although angioplasty carries a lower risk profile than open surgical alternatives, several complications may occur:

• Arterial dissection or rupture, particularly in calcified vessels or with inappropriate balloon size.
• Embolisation of plaque debris downstream, potentially causing tissue ischaemia.
• Pseudoaneurysm formation at the access site.
• Radiation-related skin injuries from fluoroscopic exposure.
• Cerebral hyperperfusion syndrome in carotid angioplasty, which may lead to stroke.
• Restenosis, which can occur due to neointimal hyperplasia and may be more frequent than with surgical bypass procedures.

Drug-eluting balloon angioplasty reduces restenosis and late lumen loss in femoropopliteal disease. Paclitaxel-coated stents and balloons, while effective in reducing target lesion revascularisation, have been associated with increased late mortality, prompting ongoing investigation.

Adjunctive Therapy

Adjunctive techniques enhance the success of angioplasty in complex lesions.
Rotational atherectomy (rotablation) employs a diamond-coated burr rotating at high speed to ablate calcified plaque, facilitating subsequent balloon dilation and stent delivery. It is especially valuable in treating heavily calcified or tortuous coronary arteries. Its use, however, requires specialised equipment and operator expertise.
Other adjuncts include cutting balloons, laser atherectomy and intravascular lithotripsy, each used according to lesion characteristics.