The National Institute for Health and Clinical Excellence (NICE) has issued full guidance to the NHS in England, Wales, Scotland and Northern Ireland on Percutaneous closure of patent foramen ovale for the secondary prevention of recurrent paradoxical embolism in divers.

NICE has also written guidance on this procedure for:


The foramen ovale is a hole in the wall that divides the two upper chambers of the heart. The hole is present in the heart of a developing fetus, but normally closes up soon after the baby is born. If it fails to close it is known as a patent foramen ovale (PFO) and in most people causes no problems. However, some studies have shown that having a PFO can increase the chance of substances (e.g. gas bubbles or blood clots) crossing from the right side into the left side of the heart, and from there into the arterial circulation where they may block blood vessels and cause serious problems such as a stroke. In divers resurfacing too quickly from a dive, bubbles of gas can form in the veins and cross into the arterial circulation causing permanent damage with stroke-like symptoms.

This procedure involves passing a device through a large vessel in the groin up into the heart and closing/blocking the hole in the wall. The aim is to lower the chances of substances crossing the heart and causing serious problems.

Coding recommendations

K16.5 Percutaneous transluminal closure of patent oval foramen with prosthesis

Y53.- Approach to organ under image control

Note: Codes within category Y53.- are used as secondary codes to classify interventions that are percutaneous and require some form of image control: if the method of image control is unspecified, Y53.9 Unspecified approach to organ under image control is assigned.

In addition the ICD-10 codes Q21.1 Atrial septal defect is assigned. The site of the embolism is also coded when present.

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