D . Y . PATIL SCHOOL OF MEDICINE ,NERUL , NAVI MUMBAI

Dr. Apurva Kalra MD Radiology 3rd Year Resident

• A 69 year old male patient presented with chest discomfort.

• There were ischemic changes seen on his ECG

• PAST HISTORY- He had undergone deployment of a stent in the right coronary artery and left anterior descending (LAD) 3 years ago

• Patient was subjected to 2D Echo which showed presence of endocarditis and hypokinesia in the inferior wall of left ventricle.

• Ejection fraction was normal

• Also to be noted were soft tissue lesion around right ventricle and pericardiac region however this was inconclusive.

• Hence Catheter Angiography and Cardiac MR were carried out for further evaluation .

Catheter angiography was carried out

LAD stent was unremarkable.

However the Right coronary stent showed occlusion

MR cardiac was advised for soft tissue evaluation

Post contrast study short axis views showed peripheral enhancement with central hypointensity in the region of right ventricle and pericardium.

MR shows Four chamber view post contrast study

On delayed enhancement Short axis view: Enhancing non viable tissue noted in inferior wall of left ventricle and an enhancing soft tissue mass.

CT Coronary Angiogram was carried out for further

investigations

CT Angiography

• Stent is bent at 2 sites with complete fracture in its mid part

• A peripherally enhancing collection with central necrosis was noted around the RCA at the level of the stent

• The stent had perforated the RCA and was surrounded by fluid collection which formed a Chronic Abscess.

• The Stent was completely thrombosed and distal post stent RCA showed no opacification of contrast beyond the fractured site

3 D CORONARY ANGIOGRPAHY

• Patient was put on medical therapy , given antibiotics and was advised regular follow ups.

• On follow up 2D scan the soft tissue mass had regressed significantly.

The majority of studies report the incidence of SF between 1 and 8%2

The incidence of SF in RCA was the highest while left main (LM) stents were less likely to fracture2.

Causes of Stent fracture:

•Fracture of the stent can be due to shear forces resulting from cardiac contractions.

•Excessive tortuosity or angulation of vessels( seen in right coronary artery stents)

•Overlapping stents, and long stents.

•Additional technical factors include inappropriate handling, high-pressure deployment, stenting in calcified segments, and manufacturing flaws.

Stent fracture has been classified into 5 grades:

I (single-strut fracture)

II (≥2 strut fracture)

III (≥2 strut fracture with deformation)

IV (fracture with transsection but without gap)

V (fracture with transsection and gap between stent segments)

Consequences of stent fracture

•In-stent restenosis

• Stent thrombosis

•Coronary aneurysm

•Sudden cardiac death.

Take Home Message • Not all SFs can be detected with conventional

angiography; therefore, many patients might be treated as stent thrombosis or stenosis without the detection of SF, if sensitive diagnostic imaging modalities especially CT coronary angiography are not used.

• Non invasive cardiac imaging specially CT coronary angiography is the modality of choice and it should be done in such cases.

References

1. Cerqueira M.D., Weissman N.J., Dilsizian V.; Standardized myocardial segmentation and nomenclature for tomographic imaging of the heart: a statement for healthcare professionals from the Cardiac Imaging Committee of the Council on Clinical Cardiology of the American Heart Association. Circulation. 105 2002:539-542.

2. Mohammed Khalil Mohsen, Awad Algahtani and Jassim Al suwaidi Stent Fracture: How Frequently Is It Recognized? Heart Views. 2013 Apr-Jun; 14(2): 72–81.

3. Shaikh F, Maddikunta R, Djelmami-Hani M, Solis J, Allaqaband S, Bajwa T. Stent fracture, an incidental finding or a significant marker of clinical in-stent restenosis? Catheter Cardiovasc Interv. 2008;71:614–8.

ACKNOWLDGEMENTS

DR.MADAN MANMOHAN

DR.OM TAVRI

DR.TAHIR

DR.PRATIK PATIL

DR. SANJAY PASORIA