A Case of Three Consecutive Events of Acute Myocardial Infarctions in Three Different Vessels
On September 25, 2012, a 51-year-old man visited the emergency room for acute retrosternal squeezing chest pains for the past twelve hours. He had no history of diabetes mellitus, hyperlipidemia, and nor a familial history of coronary artery disease. However, he was a current smoker (30 pack years). He had hypertension and history of two consecutive acute MI.\nThe first acute MI was on February 21, 2000. The electrocardiogram (ECG) showed ST-segment elevations in the inferior leads (II and aVF) and the anterior (V 2-4) leads (). The peak levels of creatine kinase-MB (CK-MB) and troponin T were 31.71 and 2.51 ng/mL. The coronary angiography was performed. The coronary angiography showed a total occlusion with thrombus and Thrombolysis in Myocardial Infarction (TIMI) 0 distal flow in the proximal portion of the left anterior descending from the coronary artery (LAD), which was successfully treated with a bare metal stent (3.0×15 mm, NIR Royal® stent, Boston Scientific Corporation, Natick, MA, USA). In addition, he had taken aspirin 100 mg, atenolol 25 mg, captopril 37.5 mg and simvastatin 10 mg once daily and cilostazol 100 mg twice daily, on a regular basis after the first MI event.\nThe second acute MI was on December 30, 2007. The ECG showed ST-segment elevation in the inferior (II, III, and aVF) leads (). The peak levels of CK-MB and troponin T were 164.7 and 4.01 ng/mL. Emergent coronary angiography was performed. The coronary angiography showed total occlusion with thrombus, with TIMI 0 distal flow in the mid portion of the right coronary artery (RCA), which was successfully treated with a paclitaxel eluting stent (4.0×24 mm, TAXUS®, Boston Scientific Corporation, Natick, MA, USA) (), and a 95% restenosis in a stent with thrombus, and TIMI 0 distal flow in the proximal portion of the LAD, which was successfully treated with a zotarolimus eluting stent (2.75×30 mm, ENDEAVOR®, Medtronic Inc., Minneapolis, MN, USA) and overlapping a sirolimus eluting stent (3.0×23 mm, CYPHER®, Cordis Corporation, Warren, NJ, USA) (). There were no other stents for appropriate lesion lengths and sizes, except ENDEAVOR and CYPHER stents at that time.\nHe had taken aspirin 100 mg, clopidogrel 75 mg, ramipril 2.5 mg and simvastatin 10 mg once daily and molsidomine 2 mg twice daily, on a regular basis after a second MI event.\nAt the third acute MI, physical examination showed that his blood pressure was 90/60 mm Hg, the heart rate was 64/min, and respiratory rate was 20/min. He had a regular heart beat and clear heart sounds without murmurs.\nElectrocardiogram showed Q-wave and ST elevation in the V 1-5 and T-inversion in V 4-6 (). The peak levels of CK-MB and troponin T were 17.84 and 0.741 ng/mL.\nEchocardiographic evaluation revealed aneurysmal changes at the apicoseptal wall in the left ventricle, and ischemic insult in the LAD and the RCA territory. An ejection fraction of 40% was observed.\nEmergent coronary angiography showed a total occlusion with thrombus and TIMI 0 distal flow in the proximal portion of the left circumflex coronary artery and collateral flow from RCA, which was successfully treated with a zotarolimus eluting stent (3.5×22 mm, RESOLUTE INTEGRITY®, Medtronic Inc., Minneapolis, MN, USA) (). After primary percutaneous interventions, the patient became stable without chest pains and was discharged on the fourth hospital day.\nHematological analyses were performed and showed the following results: D dimer 0.38 ug/mL (<0.5 ug/mL), antithrombin III 107% (80-120%), protein C activity 131% (70-130), and protein S activity 90% (70-130). In addition, immunological analyses were performed and indicated the following results: lupus anticoagulant titer 1.01 (0.8-1.2), anti-beta2-glycoprotein1 immunoglobulin G/M titer negative/negative, anti-cardiolipin antibody immunoglobulin G/M titer negative/negative and homocystein 12.33 umol/L (5.08-15.4 umol/L). Further, the platelet drug response assay was also performed and displayed the following results [The results of the assay are reported as absolute P2Y12-Reaction-Units (PRU), as well as percent inhibitions (% inhibition), the latter calculated as 100-(TEST/BASE×100) or {(BASE-TEST)/BASE}×100]: PRU 215 (0-240), % inhibition 31% (20-80). He was discharged after uneventful recovery with triple anti-platelet therapy using aspirin 100 mg and clopidogrel 75 mg once daily and cilostazol 100 mg twice daily. He had also been treated with ramipril 2.5 mg, bisoprolol 2.5 mg and rosuvastatin 10 mg once daily and molsidomine 2 mg twice daily. The patient has been followed-up at the outpatient department without further symptoms.