Myocardial infarction in the young

Myocardial infarction in persons aged below 45 years is a rareevent, usually not related to coronary atherosclerosis, but mostly oc-curs as a consequence of cocaine abuse, congenital coronary abnor-malities, or spasm. We present the case of a young man with anacute anterior myocardial infarction caused by a rare protein defi-ciency in the coagulation system.A29‐year-oldman,of Africandescent,withnopriorhistoryof car-diac event, presented at our emergency department complaining ofsevere acute chest pain radiating to the left arm. Electrocardiographyshowed 2 mm ST elevation in V1 to V4. Transthoracic echocardiogra-phy revealed akinesia of the anterior wall and apex with mild globaldysfunction (ejection fraction 50%). Loading doses of ASA andclopidogrel were administered before coronary angiography thatshowed a large proximal thrombus in the left anterior descending cor-onary artery (LAD) causing total occlusion. Intracoronary abciximabwas administered, and, given large clot burden, thrombus aspirationwas performed before deploying two bare metal stents. At the endof the procedure the patient developed cardiogenic shock requiringadrenaline administration and IABP. Despite arterial patency beingrestored, TIMI flow 1 persisted in the LAD (Fig. 1A).Afterwards,contrast-enhancedcardiacmagneticresonance(CMR)showed transmural infarct of left ventricular apex that appeared thinand akinetic and multiple necrosis foci on interventricular septum(Fig. 1B). A complete thrombophilic screening was carried out, finallyrevealing a combined deficiency of proteins S and C: plasma protein Cand S concentration were respectively 39% and 43% of normal. A ther-apy with low molecular weight heparin was started at a dosage of6000 IU once daily, and 12 months dual antiplatelet therapy was rec-ommended. Two months later therapy was converted to oral antico-agulant with dabigatran 220 mg once daily. At 6 months follow up,the patient remained asymptomatic. Family history revealed recur-rence of severe thromboembolism among his relatives.Protein C is a vitamin K-dependentprotein, synthesized in theliver,that inactivates coagulation factors Va and VIIIa, which are required tothrombin generation and factor X activation. This process is stronglysupported by protein S activity as cofactor. Moreover Protein C hasestablished antin flammatory activity and seems to harbor cyto-protectivepropertiesonendothelialcells.Itisestimatedthatcongenitalprotein C deficiency is present in 2 to 5% of patients with thromboem-bolism [1]. Prevalence of clinically symptomatic deficiencies of proteinC in the general population lies between 1:16,000 and 1:36,000 whilethat of symptomatic protein S deficiency is 1:20,000. Both protein Cand S deficiencies are associated with increased risk of developingdeep venous thrombosis (risk ratio 8.1 for protein S deficiency and 7.3for protein C deficiency) [2] and higher risk of recurrent thrombosis,with typically young age of onset and family cluster occurrence. Thefew available reports of families with combined protein C and S defi-ciency suggest that both genes segregate independently as an autoso-mal dominant trait. Although venous district is typically involved(deep veins, pulmonary artery, jugular vein), arterial thrombosis hasbeen reported. Aorta, mesenteric and cerebral arteries can be affected[3]. Patients with C protein deficiency are at potential risk of warfarininduced skin necrosis, and for that we preferred LMWE and dabigatranto vitamin K antagonist.After acute myocardial infarction inadequate tissue perfusion mayoccur despite early and successful reopening of the infarct-related ar-tery with primary percutaneous coronary intervention. This situation,known as “No Reflow” (NR), significantly affects outcome [4]. NR canbe related to ischemia-reperfusion injury or to downstream emboli-zation of atherosclerotic material into the microvasculature. CMR al-lows the detection of myocardial injury with high accuracy: theintensity of myocardial enhancement is related to expansion of theinterstitial volume secondary to cell necrosis; persistent hypo-perfusion on first pass contrast-enhanced images suggests microvas-cular obstruction (Fig. 2A), which impedes delivery of contrastmedium, or dysfunction of coronary microvasculature that can be re-liably assessed by positron emission tomography (Fig. 2B).Current approaches for prevention and treatment of NR includevasodilators, glycoprotein IIb/IIIa inhibitors and thrombus aspiration.Although we used all of the above, the patient did not achievesuccessful reperfusion. Thrombophilia may have contributed to ex-tensive myocardial damage through a greater and diffuse pro-