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Early attempts at percutaneous coronary intervention (PCI) using balloon angioplasty were largely hampered by technical limitations. Although balloon angioplasty was moderately successful at relieving an obstruction, the procedure frequently resulted in dissections which, if uncontrolled, often led to abrupt vessel closure. Furthermore, while acute luminal gain could be impressive, a combination of elastic recoil and smooth muscle hyper-proliferation often negated the benefits of an acceptable immediate angiographic result. Elastic recoil could occur minutes to hours post-procedure resulting in acute myocardial infarction (AMI) and need for emergent coronary artery bypass grafting (CABG). This led to a pivotal development in the history of PCI with introduction of the metallic stent, which drove rapid improvements in short- and long-term procedural safety and efficacy. Stent design has been a remarkable area of technological advances with pivotal milestones including evolution of metallic architecture and introduction of the drug-eluting stent (DES). Although DES is now considered the default option for most PCI, bare-metal stents (BMS) still represent a sizeable proportion of stent procedures in some countries and in some settings may have arguable advantage. In this chapter we aim to review contemporary evidence for the use of BMS in modern interventional practice.

The management of ST-elevation myocardial infarction (STEMI) has evolved significantly with the introduction of new pharmacological therapies as well as interventional procedures and devices. The GISSI and ISIS-2 studies showed a mortality benefit of streptokinase over standard therapy (heparin ± oral anticoagulation)/placebo which lead to the widespread use of streptokinase in the late 1980s [1, 2]. The use of recombinant tissue plasminogen activator (rt-PA) was shown to be more beneficial than streptokinase in the TIMI and GUSTO trials [3, 4]. Results of other studies such as CLARITY and COMMIT paved the way for addition of clopidogrel to the drug regime which further reduced mortality [5, 6].

Primary percutaneous coronary intervention (PPCI) is the treatment of choice in patients presenting with ST-segment elevation myocardial infarction (STEMI). In contemporary practice, among patients who present to the hospital with STEMI, between 40 and 65% have concurrent multi-vessel (MV) coronary artery disease (CAD), a combination of a thrombotic culprit lesion and one or more significant (50% or more diameter stenosis) non-culprit lesions in other coronary artery territories on coronary angiography. Optimal management of these non-culprit lesions in this setting is still a matter of debate. STEMI patients with MV CAD are at higher risk of recurrent cardiovascular events. However, PCI of bystander lesions during PPCI can bring potential complications. The presence of MV CAD in STEMI patients often poses therapeutic dilemma for interventional cardiologists as there are multiple possible strategies and controversial data. Besides clinical relevance, as the burden of cardiovascular disease affects hospital systems around the world, there is growing interest to examine and improve the various treatment strategies involved in the management of STEMI with MV CAD.

Primary percutaneous coronary intervention (PPCI) is always targeted on the angiographically identified culprit lesion. However, the actual culprit lesion may not compromise the lumen and can be located proximally or distally to the angiographic target lesion. As a result, the risk of incomplete lesion coverage can be high when the PPCI is guided solely by angiography. Furthermore, stent implantation must be optimized, as incomplete apposition and/or edge dissection may result in in-stent restenosis or acute thrombotic events. Thus, invasive coronary imaging using intravascular ultrasound or optical coherence tomography can be useful to guide the PPCI procedure by locating the true culprit lesion and may lead to better stent coverage of the lesion. Besides, invasive imaging also helps to resolve diagnostic uncertainty and to identify the mechanisms underlying acute events.

Invasive coronary physiology is a key instrument in decision-making for the interventional cardiologist. Fractional flow reserve has been well validated in chronic stable coronary artery disease. Its practical applications have expanded into other clinical situations such as acute coronary syndrome (ACS) including ST-elevation myocardial infarction (STEMI). Recently, other invasive indices of coronary physiology including instantaneous wave-free ratio (iFR), index of microvascular resistance (IMR), hyperemic stenosis resistance (HSR), and coronary flow reserve (CFR) have been explored in the context of ACS. This review will focus on the fundamentals and role of physiologic lesion assessment in the ACS patient.

Coronary artery bypass grafting (CABG) is one of the most commonly performed procedures worldwide. Its place in the treatment of coronary artery disease has been established for decades with the benefits of CABG versus percutaneous coronary intervention (PCI) in various scenarios being extensively investigated. Recent major landmark randomised clinical trials such as SYNTAX, EXCEL and NOBLE have helped to define the patients in which each approach is likely to be most successful. Indeed, the last decade has seen most centres embrace the “Heart Team” concept, whereby a collaborative approach helps to optimise patients’ outcomes.

Although substantial progress has been made in recent decades in reducing mortality and performing optimal revascularization in patients with acute coronary syndrome (ACS) and stable coronary artery disease (CAD), one of the remaining challenges is to better prevent and treat extended myocardial damage despite “apparent” angiographic optimal percutaneous coronary intervention (PCI). The presence of no-reflow is related to higher risk of major adverse cardiac events (MACE) due to the poor healing of the infarct, adverse left ventricular remodelling, congestive heart failure occurrence and death. Despite optimal epicardial coronary artery reperfusion performed by PCI, distal microembolization into the coronary microcirculation limits myocardial salvage especially during ACS. No-reflow represents the ultimate stage of extended myocardial damage after PCI with absence of contrast medium progression in the coronary artery. This complication occurs mainly during ACS or during PCI of rotational atherectomy and venous graft in stable patients. The objective of this chapter is to describe how to manage a no-reflow phenomenon from the pathophysiology to the management in order to help physician to prevent this complication and if no-reflow occurs adapt therapeutics to limit myocardial damage and reduce poor outcomes.

Shock is circulatory failure with inadequate cellular oxygen utilization. Four potential pathophysiological mechanisms result in shock, including hypovolemic, cardiogenic, obstructive, and distributive factors. Cardiogenic shock (CS) decreases myocardial contractility and is the most common cause of death in patients with acute myocardial infarction (AMI). To differentiate the type and cause of shock, medical history, physical examination, and clinical investigations are important. Focused echocardiography offers advanced information for differentiation and should be performed as soon as possible in any shock patient.

Cardiogenic shock (CS) occurs in approximately 8–10% of patients with ST-elevation myocardial infarction (STEMI). While immediate percutaneous coronary intervention (PCI) continues to be the mainline treatment strategy, mortality remains as high as 40% before hospital discharge. Even after hospital discharge, survivors of cardiogenic shock complicating myocardial infarction (CSMI) often suffer from severe heart failure and its consequences, including repeated hospitalization and high mortality. Mechanical circulatory support (MCS) devices during CSMI PCI can be lifesaving by supporting poor ventricular function while decreasing myocardial wall stress and relieving ischemia. In this chapter, we review the definition and pathophysiology of CSMI, the major ventricular support devices, an algorithm for MCS use in STEMI, relevant data, and a prototypic case that illustrates CSMI management augmented by MCS.

With timely reperfusion, myocardial loss following myocardial infarction (MI) can be significantly reduced and may limit the incidence of mechanical complications. However, with improving treatment of those with larger or delayed presentation MI, appropriate management of mechanical complications remains a key consideration for those working in heart attack centers.