by A Colombo

Operators: Alessandro Colombo MD, Paolo Danna MD
Catheterization Laboratory
Luigi Sacco Hospital

Milan, Italy

A 54 year-old gentleman came to the Emergency Room of our Hospital because of severe chest pain and shock, with an ECG pattern of a large anterior AMI. Coronary angiography was carried out 90 minutes after the onset of symptoms and showed a normal, dominant right artery and extensive thrombosis of the left main artery with almost no antegrade flow (Figure 1).

An IABP was immediately placed and a pharmacologic strategy was chosen instead of balloon: alteplase 50 mg was injected into the left main trunk and eptifibatide 180 micrograms/kg double bolus + 2 micrograms/kg/min i.v. Balloons were rejected as a first-line treatment because of concern that downstream dislodgement of such a huge thrombus could precipitate irreversible no-reflow. As a consequence of pharmacologic intervention, the hemodynamic status stabilized and angiography showed a marked reduction of the thrombus with improved flow (Figure 2, taken 30 minutes after starting the drugs).

At this point, mechanical thrombectomy was carried out with the X-Sizer™ device after which a sizable reduction of the clot was observed (Figure 3) with TIMI 3 flow. Blood pressure increased to 130/80 mmHg, chest pain resolved almost completely, and a significant reduction of ST-segment elevation was recorded on the ECG.

A 3.5 x 15 mm. PTCA balloon was then inflated thrice at the point of the residual coronary obstruction (Figure 4). Thereafter, the clinical signs of low output disappeared and the subsequent hospital stay was uneventful, apart from blood loss at the arterial catheterization site that required transfusion. A peak CK-MB value of 1095 U/l was recorded 11 hours after the onset of symptoms.

I.V. eptifibatide and heparin were infused up to day 2. Later on, eptifibatide was replaced with ticlopidine. An inherited thrombophilic state was excluded with the appropriate studies.

An echocardiographic study on day 1 showed marked antero-lateral asynergy with 40% left ventricular ejection fraction that increased to 50% on day 16. The patient underwent control coronary angiography on day 9. At that time a small, rounded thrombus was still present in the left main trunk (Figure 5). Coronary flow velocity was normal and IVUS imaging showed thrombus and atheroma with 50% reduction of the left main cross-sectional area. It was not possible to retrieve the thrombus with the X-Sizer™ aspiration catheter; therefore, the decision was to perform CABG, because of the risks associated with a new, extensive thrombotic relapse. On day 19, the left thoracic artery was connected to the anterior descending artery off-pump. The patient was discharged on day 25 in good condition.

What we learned from this case is that patients may survive complete thrombosis of the left main coronary stem if a well developed right coronary artery is present and if aggressive pharmacologic and catheter-based dethrombosis are attempted before ballooning.