Introduction: ST-elevation myocardial infarction re-presents a major diagnostic and therapeutic emergency that requires interventional revascularization as soon as possible. Despite the increasing percentage of pati-ents that benefit from primary angioplasty with impact over mortality, the outcome of a patient with myocar-dial infarction remains unpredictable, situations in which associated complications such as arrhythmias call for prompt and complex management. The pre-sence of ventricular arrhythmias beyond the first ho-urs of STEMI, in the absence of recurrent myocardial ischemia, is associated with unfavourable outcome. Implantation of an internal cardioverter defibrillator is necessary as part of secondary prevention of sudden cardiac death. Moreover, supraventricular arrhythmias are also linked to unfavourable outcome. In certain si-tuations, ablation procedures are required.

Methods: We present the case of a 62-year old patient with multiple cardiovascular risk factors, presented to E.R. of the regional hospital for typical angina, started 10 hours before presentation. Electrocardiogram show-ed 1-2 mm ST elevation with R wave amputation in DII, DIII and aVF. The patient was transferred to our Clinic as part of RO-STEMI national program for emergency coronary arteriography.Angiography revealed bivas-cular coronary atherosclerotic disease with chronic occlusion of mid-proximal anterior interventricular artery and critical proximal stenosis of circumflex ar-tery at the bifurcation of first marginal artery which has a sub-occlusive ostial stenosis. Percutaneous coronary angioplasty with implantation of a stent at the site of the culprit lesion was performed, with TIMI 3 flow in the circumflex artery, but with plaque shift in the mar-ginal artery and occlusion, without possibility of revascularization. Initial evolution was favourable, but on the intended discharge day ECG showed asymptomatic fast rate typical atrial flutter. Because of the uncertain debut, transesophageal ultrasound was performed whi-ch contraindicated cardioversion. Oral anticoagulation and heart rate control treatment was initiated. After three days, spontaneous conversion to sinus rhythm occurred. The next day, the patient developed cardio-pulmonary arrest caused by polymorphic ventricular tachycardia (VT), which was promptly resuscitated.

Results: Over the next days, the patient had recurrent polymorphic VT, initiated by monomorphic ventri-cular premature beats (likely of Purkinje fiber origin, suggesting acute ischemia), requiring repeated electri-cal conversion and i.v. antiarrhythmic treatment with amiodarone and lidocaine, high-dose beta blockade and mild sedation. Coronary angiography was repea-ted without any new changes, however, slow flow was noted in a very small branch of the circumflex artery, the likely cause of ischemic ventricular arrhythmia, without possibility of revascularization. After 5 days, the patient remained free of sustained ventricular ar-rhythmia. Consequently, a dual-chamber internal car-dioverter defibrillator was implanted, followed by ra-diofrequency ablation of cavotricuspid isthmus later on. Eventually, after one month, myocardial perfusion scintigraphy was performed, showing myocardial vi-ability in the territory of anterior interventricular ar-tery; recanalization of chronic occlusion was carried out with optimal result. The patient was pain-free, wi-thout heart failure symptoms or ventricular arrhythmi-as. Particularities and discussion: This presented case brings in discussion the unpredictable and winding history of an inferior STEMI, with favourable outco-me at first despite the suboptimal interventional re-sult, complicated afterwards with supraventricular and acute ischemic ventricular arrhythmias that required multiple antiarrhythmic treatment regimens and two electrophysiologic procedures during the same hospi-tal stay. The indication of an internal defibrillator early after myocardial infarction in patients with ventricular arrhythmias after 48 hours of STEMI onset, should be taken into consideration in individual cases.

Conclusions: Moreover, testing of myocardial viability with scintigraphy turns out to be an important decisio-nal factor regarding the management of chronic coro-nary occlusions.

Conclusions: This case depicts the scenario of a patient with a common disease, complicated by multiple un-predictable events, that required individual therapeutic approach. In spite of prompt interventional treatment of STEMI patients, close monitoring of these patients should not be neglected, especially in situations in whi-ch the initial result is not optimal. Therapeutic soluti-ons should be considered for the majority of complica-tions after myocardial infarction, no matter the gravity, provided that they are identified on time.