Dr Teh-Kuang Sun

Section of cardiology

Puli Christian Hospital

Taiwan

Patient’s profile

Mr Wu , 48 y/o male

Past Hx :

HTN since age of 30, irregular compliance to medical control

Obesity ( BH 152 cm, BW 68kg, BMI 27.2)

Heavy smoker ( 1-2 ppd) since age of 18

Hepatitis B

PUD

FH : father HTN / IHD, mother HTN

Present illness

On the day of admission, angina since 7:00

AM, associated symptoms are diaphoresis,

nauceas and dyspnea.

At arrival to ER:

Intermittent bradycardia ( HR 35-50 bpm),

hypotension ( SBP around 70-100 mmHg)

ECG: limb leads II III AVF ST elevation.

inferior wall STEMI impressed.

ECG at arrival to ER

Primary PCI

Pre-medications at ER :

Heparin sulfate 4000 u, iv stat.

Aspirin 300 mg and clopidogrel 300 mg, po

stat.

Morphine 3 mg, iv , for pain control

O2 by nasal prong, 2-3 l/min

IV fluid: normal saline 100 ml/hour

At cath-lab:

For bradycardia: Temporary pacemaker ,

via right femoral vein

Additional Heparin sulfate 3000 u, iv stat,

immediately prior to initiate PCI, to keep

ACT > 250 sec.

Patient had vomited once in cathroom.

Metoclopramide HCL 10 mg iv st was

given

CAG: left coronary artery

RCA: total occlusion on mid-RCA

Target lesion: mid-RCA total occlusion

Catheter: 7Fr, JR 4.0

PTCA wire: 0.014 Fielder FC wire

PTCA balloon: Terumo Ryujin 2.75x15

mm

PTCA: balloon dilatation. Ryujin 2.75x15mm, 8 atm.

TIMI III flow achieved. Residual stenosis > 60%

Deployment of stent on RCA-middle segment:

Liberte 3.0x 28 mm, 18 atm.

Post stenting: distal RCA spasm and impaired flow

NTG 200 ug, intracoronary st.

A spiral dissection from distal stent edge to distal RCA was seen.

A second stent was deployed for distal RCA.

Liberte 2.75x28mm, 16 atm. TIMI III flow.

After primary PCI, patient was admitted to ICU, free of angina,

stable hemodynamic and heart rate with ECG showing ST

resolution.

But a hour later …

patient had chest pain again with ECG change!!

A glycoprotein IIbIIIa ( GP IIbIIIa)

antagonist Tirofiban intravenous loading

infusion and then continue infusion was

started , in addition to Heparin sulfate iv

infusion.

Morphine 3 mg iv for pain control

Back to cath lab, acute massive in-stent thrombosis was seen on RCA. Using

7Fr JR 4.0 guiding catheter , Runthrough NS PTCA wire crossed the vessel

smoothly.

Export aspiration device was used for thrombus aspiration.

TIMI III flow regained. Thrombus were aspirated, but in angiography

remained residual thrombus within the two stents

We decided to use balloon dilatation to compress and squeeze the

remaining in-stent thrombus.

Abbot voyager balloon 3.0x20 mm, 14-16 atm, in-stent dilatation. Post

dilatation, angiography showed free of remaining thrombus.

Lessons to learn from this experience …

Post stenting distal vessel spiral dissection.

Maintain the wire across the lesion

If the dissection is long and the flow is

impaired, with vessel diameter > 2.5mm, the

lesion should be stented promptly in its full

length.

If the stent edge dissection is minor, with

residual lumen > 50%, without impairment of

flow, there’s no need of further treatment.

Anticoagulation during PCI

Loading dose of oral aspirin with either clopidogrel or GP IIb IIIa antagonist are indicated ( class I indication)

Use unfractionated heparin ( Class I indication)

This patient had vomited … is this the reason that full antiplatelet effect had not achieved, after the oral loading dose of dual antiplateletdrugs?

It’s reasonable to start GP IIbIIIa antagonist ( tirofiban / eptifibatide) at time of primary PCI in selected patient ( Class IIa indication).

Management of acute in-stent thrombosis

Remember the risk factors for acute thrombosis are:

undersized stent, dissection, TIMI flow post MI, CAD > 50% stenosis proximal to the culprit lesion, malignancy, no aspirin at time of PCI, and LVEF< 30%.

Emergency PCI is the treatment of choice, back to cath-lab as soon as posible, the strategy is same as used in STEMI.

Thrombus aspiration device is a useful

tool.

Concomitant antiplatelet medication with

use of glycoprotein IIbIIIa antagonist is

indicated by the present guidelines ( II

a ).

Full anticoagulation is essential.

What to do if you have done all above and still remain

some residual thrombus?

May consider use of balloon dilatation to

compress and squeeze residual thrombus

against the deployed stent and vessel wall.

But… It’s a dangerous move!

It only can be done if most of the thrombus

are removed by thrombus aspiration device

or distal protection devices like GuardWire,

and no remaining thrombus are are seen on

bifurcations / nearby branches