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Majority of acute myocardial infarctions (MI) are caused by rupture of a fixed atherosclerotic plaque with subsequent thrombus formation, with coronary angiography showing significant coronary artery obstruction [1]. While the absence of angiographic evidence of significant coronary stenosis may challenge the diagnosis of MI, significant coronary pathology may be present despite subtle or mild lesions seen on angiography. MI with non-obstructive coronary arteries (MINOCA) is a syndrome with different causes characterized by evidence of MI with non-obstructive coronary arteries on angiography. Moreover, spontaneous coronary artery dissection (SCAD) is an important cause of non-atherosclerotic MI among patients presenting with acute coronary syndrome (ACS). The management of patients with MINOCA is specific to the underlying cause and therefore routine evaluation for underlying causes is strongly encouraged. Optical coherence tomography (OCT) is a powerful intracoronary imaging modality that can be used to delineate the underlying pathophysiologic cause of MI. In this chapter, we will review the differential diagnosis of MINOCA and utility of OCT in differentiating between these causes. The main focus of this chapter is to discuss spontaneous coronary artery dissection (SCAD) and the appropriate use of OCT in the diagnosis and management of this clinically important entity.

The success and procedural complexities of percutaneous left atrial appendage (LAA) closure depends largely on the LAA anatomy, and on the anatomic relations between access to the left atrium via the fossa ovalis to the LAA. These anatomic features and three-dimensional cardiac structural relationships are distinctly depicted on cardiac computed tomography angiography (CCTA), especially since the LAA has minimal dynamic role during the cardiac cycle. The spatial resolution and three-dimensional structural depiction of CCTA offers unique imaging planes not appreciated with transesophageal echocardiography (TEE), which has been the conventional pre-imaging modality-of-choice for LAA closure. As with other structural cardiac interventions, the noninvasiveness, superiority in imaging resolution and relational portrayal have progressively established CCTA as instrumental preplanning imaging tool, and is anticipated to overtake TEE as the pre-imaging modality-of-choice for LAA closure. For preplanning imaging, CCTA allows not only anatomic LAA assessment, but also ruling out preexisting thrombus in the LAA that would exclude attempt at LAA closure. In addition, post-surveillance of LAA closure is necessary to rule out device-related thrombus and residual leak, and CCTA can contribute to this important role. This chapter will review the practical utility of CCTA in preplanning and guiding LAA closure, and post-procedural surveillance.

Atrial fibrillation (AF) is the most common cardiac arrhythmia in adults, affecting 1–2 % of the general population and over 10 % of individuals over age 80 [1, 2]. With aging of the population, the prevalence of AF and its impact on global healthcare system is projected to increase substantially. The true prevalence of AF may also be underestimated since it may be challenging to detect paroxysmal AF or occult asymptomatic AF. AF is associated with considerable morbidity and mortality, especially being an independent risk factor for stroke, increasing the risk of ischemic stroke by 4–5 fold after adjusting for other risk factors [3]. In fact, AF is detected in up to 19 % of stroke patients over the age of 70 [3]. Furthermore, cardioembolic strokes related to AF are more severe than other types of ischemic stroke and are associated with higher 30-day and 1-year mortality [4, 5]. Annually, 800,000 strokes occur in the U.S., with 1.5 % of these attributed to AF for those under 59 and 23 % of those >80 years of age [3]. Stroke is the third leading cause of death and the number one cause of major morbidity in the U.S. and is estimated to cost the healthcare system ~30 billion dollars annually.

The vast majority (>90 %) of complications related to left atrial appendage (LAA) closure are procedure-related, occurring within 7 days of the index procedure [1]. These complications attenuate the overall clinical benefit of this strategy for stroke prophylaxis in patients with non-valvular atrial fibrillation and highlight the importance of the safe execution of the procedure to maximize the overall clinical benefits of LAA occlusion in this patient cohort [2]. The current chapter will outline the major procedural complications of LAA closure and discuss their management. Although a large number of LAA occlusion devices have now been developed [3], the majority of the discussion will center around second generation devices for which there is reasonable registry or randomized trial data available (i.e., WATCHMAN, Boston Scientific, and Amplatzer Cardiac Plug (ACP), St Jude Medical).

The approach of percutaneous left atrial appendage (LAA) closure for stroke prevention in patients with atrial fibrillation (AF) has rapidly advanced over the past two decades. Numerous devices are under clinical investigations and several are already CE-marked. The Amplatzer Cardiac Plug (ACP) is the third commercial device manufactured specifically for endovascular LAA closure, and real-world experience to-date has shown good safety and clinical efficacy. The second-generation ACP device, Amulet, has just been re-launched. This paper reviews in-depth the device characteristics and procedural techniques of the ACP and Amulet devices.