New concept: occlusion (OMI) and non-occlusion myocardial infarction (NOMI)

The article deals with an important problem of managing patients with myocardial infarction (MI). It’s known that the greatest benefit of immediate invasive intervention obtains patients with acute occlusion of the coronary arteries (or subocclusion). However, numerous studies have shown that up to 30 % of patients classified as non-ST segment elevation myocardial infarction (NSTEMI) are consistently found to have missed acute coronary occlusion. At that time, a number of patients with «benign» ST elevation undergo unnecessary catheterisation +/- reperfusion therapy that increases the risk of complications. In 2018 Meyers P., Weingart S. and Smith S. noted that ST elevation on ECG is most likely an unreliable tool for detecting patients that will benefit from immediate percutaneous coronary intervention (PCI) and that a shift is required to a more reliable paradigm for detecting acute coronary occlusion, than the concept ST-elevation myocardial infarction. The authors introduced us to the new concept of Occlusion Myocardial Infarction (OMI) and Non-Occlusion Myocardial Infarction (NOMI). In this article we discuss five examples of ECG with occlusive myocardial infarction (OMI).

Pulseless Electrical Activity as the Initial Cardiac Arrest Rhythm: Importance of Preexisting Left Ventricular Function

Background Pulseless electrical activity (PEA) is a common initial rhythm in cardiac arrest. A substantial number of PEA arrests are caused by coronary ischemia in the setting of acute coronary occlusion, but the underlying mechanism is not well understood. We hypothesized that the initial rhythm in patients with acute coronary occlusion is more likely to be PEA than ventricular fibrillation in those with prearrest severe left ventricular dysfunction. Methods and Results We studied the initial cardiac arrest rhythm induced by acute left anterior descending coronary occlusion in swine without and with preexisting severe left ventricular dysfunction induced by prior infarcts in non–left anterior descending coronary territories. Balloon occlusion resulted in ventricular fibrillation in 18 of 34 naïve animals, occurring 23.5±9.0 minutes following occlusion, and PEA in 1 animal. However, all 18 animals with severe prearrest left ventricular dysfunction (ejection fraction 15±5%) developed PEA 1.7±1.1 minutes after occlusion. Conclusions Acute coronary ischemia in the setting of severe left ventricular dysfunction produces PEA because of acute pump failure, which occurs almost immediately after coronary occlusion. After the onset of coronary ischemia, PEA occurred significantly earlier than ventricular fibrillation (<2 minutes versus 20 minutes). These findings support the notion that patients with baseline left ventricular dysfunction and suspected coronary disease who develop PEA should be evaluated for acute coronary occlusion.

A ‘shark’-masked electrocardiogram: case report of a Tako-Tsubo syndrome

Background Triangular ST-segment elevation or ‘shark-fin’ sign has been described as a specific indicator of acute coronary occlusion and large myocardial ischaemia, translating into poorer prognosis. However, this electrocardiographic presentation has been reported in rare cases of Tako-Tsubo syndrome and associated with more severe physical stressors and neurological involvement. Case summary We present a rare case of a 51-year-old woman presenting with incoming epileptic attacks and concomitant pyometra. Despite controlling epilepsy with phenytoin and the surgical treatment of the infection, she developed sepsis requiring vasopressors, and thereafter sustained ventricular tachycardia and diffuse ST-segment elevation with the ‘shark-fin’ sign. TTC was confirmed by the documentation of normal coronary arteries and the complete recovery of wall motion abnormalities at discharge. Discussion Heterogeneous presentation and triggering conditions often challenge the diagnosis of Tako-Tsubo syndrome. The acknowledgement of different electrocardiographic and clinical manifestations can ease the diagnosis and the successful management of these patients, whose prognosis can be extremely severe in the acute phase, if unidentified.

The features of the thrombolytics use in the process of the reversal of acute coronary occlusion syndrome

The mechanism of thrombus formation is a coordinated process that is under the control of neurohumoral regulation and is influenced by a variety of external and internal factors. Any disruption in the regulatory system, activation of some factors and inhibition of others can lead to disruption in the coagulation system, affecting both the plasma and platelet links of hemostasis. The activation of platelets against the background of the existing atherosclerosis of the vessels leads to the formation of blood clots, which clog the lumen of the coronary vessels and can lead to acute myocardial infarction. Today it is well known that increased thrombus formation is not only the cause of the development of acute conditions, but also leads to the progression of the disease. The leading role in the initiation of the thrombus formation process is played by platelets, therefore, the use of antiplatelet drugs is an obligatory link in both the treatment and prevention of thrombosis. In this case, the most important is the need to restore blood flow in the coronary vessels, which provide nutrition to the myocardium. In this regard, correctly selected antithrombotic agents can take a worthy place in the treatment and prevention of cardiovascular pathology, which is based on ischemic thrombosis.