The Bioresorbable Vascular Stent Dr Albert Ko

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1 The Bioresorbable Vascular Stent Dr Albert Ko

2 Dr Albert Ko MB BS, FRACP, FCSANZ Interventional/General Cardiologist Ascot Cardiology Symposium 2013

3 Treatment Goals for Coronary Artery Disease Relieve of symptoms (quality of life) - Angina, breathlessness, tiredness, reduced effort tolerance and and overall well being Improvement in prognosis (quantity of life) - LMS stenosis of >50% diameter loss, or - Triple vessel disease and LVEF of < 40%

4 Treatment Modalities Medical drug therapy Percutaneous Coronary Intervention (PCI) Coronary Artery Bypass Grafting (CABG)

5 Medical Therapy Beta blocker Calcium channel blocker Long acting Nitrate / GTN spray ACE inhibitor Aspirin / Statin

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7 CABG Invasive / traumatic procedure risk of stroke, wound infection, longer recovery period and some having personality change +/- poor memory Problem with the longevity of Saphenous vein graft (50% blocked within 7 to 10 years) 20-25% of radial/rima graft occluded silently within the first month of surgery - Off pump for single LIMA graft +/- one other graft - Hybrid (LIMA to LAD and PCI to the rest) - Avoid sternotomy means shorter recovery period

8 Percutaneous Coronary Intervention The 1 st Revolution (80 s) Plain Old Balloon Angioplasty (POBA) High rate of restenosis up to 50% within the first 6 months High rate of procedural complications perforation, dissection, acute vessel closure leading to MI and excessive bleeding Reserve d for patients who failed medical therapy and didn t want to have CABG

9 1 st POBA and 23-Year Follow UP

10 The 2 nd Revolution (90 s)

11 PCI

12 Bare Metal Stent (BMS) Much improved outcome with a clinical instent restenosis rate of between 20-30% within the first 6 months Much reduced procedural complications and the length of hospital stay Limitation of use in complex disease such as long lesion, chronic total occlusion, bifurcation, ostial and LMS etc. because of much higher rate of clinical restenosis

13 The 3 rd Revolution (2003) Drug Eluting Stent (DES) Dramatically reduces the rate of clinical instent restenosis to <5% within the first year Expanded indications to long lesion, bifurcation, chronic total occlusion, ostial and LMS etc. Late acute stent thrombosis of about 0.5 to 1% grave consequences Late neo-atherosclerosis (due to the presence of permanent stent) as opposed to early instent restenosis (due to intimal hyperplasia in response to trauma during stent implantation)

14 Gradual in-stent restenosis as opposed to acute stent thrombosis

15 The 4 th Revolution (2012) Bioreabsorbable Vascular Stent (BVS) The scaffold starts to dissolve at 6 months and is completely disappeared in 2 years It prevents early instent restenosis because it is drug eluting It restores normal vasomotor tone /endothelial function and prevents late acute stent thrombosis and neo- atherosclerosis because it is no longer there in 2 years

16 BVS

17 OCT Intracoronary Imaging

18 To good to be true? It is made of plastic like material, therefore, it is not very strong and tractable (radial and longitudinal strength) Limited used at present to type A proximal lesion in a relatively young person Currently suitable in about 10% of patients with stable angina but not in other clinical conditions yet e.g. acute MI Technology is advancing rapidly. The sky is the limit!

19 Presenting Symptoms 57 years old man who presented with a 30 min of retrosternal chest pain at lunch which he thought was indigestion. Further chest pain the next day and he was sent to MMH. Serial Trep and ECG were normal. CV risk factors include a strong FH of IHD and Dyslipidemia In-pt ETT Completed 12 min without any symptoms and achieved > 85% target HR. Subtle ST sagging in the inferior and lateral leads at peak.

20 Coronary Angiography

21 LAD Pre/POST PCI

22 In Conclusion PCI technology has come a long way. BVS may well be the stent of 1 st choice in the next 3-5 years Expanded indication means most conditions can now be treated with stents including LMS, 3-vessel disease and chronic total occlusion which are traditionally treated with surgery Relive of symptoms and improvement in prognosis are the main goals in the treatment of CAD