Current Cardiovascular Imaging Reports

MRI is well suited for imaging vascular disease as it provides excellent soft tissue contrast and spatial resolution of the vessel wall. By generating potent contrast effects, iron oxide particles further enhance the ability of MRI to deliver functional information in a range of vascular syndromes. Larger microparticles of iron oxide (MPIO) generate sufficient contrast to enable detection of low-abundance vascular targets in vivo. Ligand-conjugated MPIO confer molecular specificity, facilitating molecular imaging of a range of specific endovascular targets. This review discusses the application of iron oxide particles in the molecular imaging of a variety of vascular syndromes. In particular, ligand-conjugated MPIO have been used for targeted molecular imaging in experimental models of atherosclerosis, thrombosis, and tissue ischemia syndromes. This provides a platform for vascular molecular imaging that could accelerate diagnosis, characterize disease progression, and measure response to treatment in a clinical setting.

Echocardiography is the imaging modality of choice for patient selection prior to left ventricular assist device (LVAD) implantation, assessment of device placement, optimization of device settings, diagnosis of device-related complications, and assessment of LV recovery. The key echocardiographic features of these devices will be highlighted in the following review. With increased utilization of LVADs as well as the development of centrifugal continuous-flow pumps, familiarity with echocardiographic imaging of LVADs is essential to optimal care of these complex patients. All echocardiographic evaluations both before and after LVAD implantation should assess for biventricular function and cavity size, valvular function and pathology, intracardiac thrombi, intracardiac shunting, cannula position and flow, aortic pathology, and pericardial effusion. RAMP testing may be utilized when device complications are suspected.

Cardiac amyloidosis is an infiltrative cardiomyopathy, most commonly due to light chain amyloidosis [AL] or transthyretin amyloidosis [ATTR]; both cause significant heart failure and mortality. This review is a comprehensive overview of radionuclide molecular imaging in cardiac amyloidosis, highlighting the latest advancements in aiding diagnosis and prognosis. Specific bone scintigraphy agents have a high sensitivity and specificity for the diagnosis of transthyretin cardiac amyloidosis. Amyloid-binding radiotracers, originally developed for imaging Alzheimer’s disease, are being employed to image light chain and transthyretin cardiac amyloidosis. There is ongoing research into the use of these tracers for precise quantification of cardiac amyloidosis, which can be used to guide therapy. Radionuclide molecular imaging techniques have a vital role in advancing the field of cardiac amyloidosis. With a broadening armamentarium of novel radio tracers and new therapeutic developments, this is an exciting area, with potential breakthroughs on the horizon.

Despite significant advances in stent design and procedural technique, stent failure remains the “Achilles’ heel” of percutaneous coronary intervention (PCI). It is important to understand the mechanism of stent failure to prevent major adverse events and improve clinical outcomes. Two-dimensional angiography alone is insufficient for elucidating the etiology of stent failure. Intracoronary imaging modalities, including intravascular ultrasound (IVUS) and optical coherence tomography (OCT) have evolved to guide optimal stent placement during PCI, and have enabled identification of the etiology behind stent failure. In this review, we discuss the mechanisms of stent failure, use and limitations of intracoronary imaging (IVUS and OCT) to assess its etiology, and future directions for its use in patients undergoing coronary stent implantation.

Coronary artery disease encompasses broad pathologies beyond atherosclerosis such as spontaneous coronary artery dissection, myocardial infarction with non-obstructive coronary artery disease, and microvascular dysfunction. These diagnoses often warrant more detailed evaluations with intracoronary imaging or functional testing. In this review, we highlight the reported sex differences in intracoronary imaging and functional evaluation of the coronary arteries. The diagnosis and treatment of women presenting with acute or chronic coronary syndromes have been fraught with disparities given the poor representation of women in trials addressing the role of conventional coronary angiography, intracoronary imaging, and coronary functional assessment. Most of the evidence for intravascular ultrasound and optical coherence tomography identified features unique to women; however, the published data do not establish validated references for women. Differences in vessel size, myocardial mass, microvascular function, hyperemic response, and plaque characteristics could explain the sex-based differences. Further evidence is required to define and validate cutoff values in women and ascertain clinical outcomes.

The goal of this review is to outline the new guidelines released by the ASE/EACVI that seek to simplify the assessment of diastolic function and evaluate the use and potential application of new and emerging technologies. The latest guidelines have decreased the number of parameters needed to evaluate diastolic function to 3. The parameters necessary include peak tricuspid regurgitation (TR) velocity, average E/e′, and indexed left atrial volume (LAVi). At least 2 out of 3 must be positive to determine diastolic dysfunction. There are certain disease states that limit the application of the new guidelines and diastolic stress testing may be indicated in inconclusive cases. New and emerging technologies such as global longitudinal strain (GLS) may provide new opportunities to determine LV filling pressures. New guidelines issued by the ASE and EACVI have simplified the assessment of diastolic function and should be implemented in daily practice.

Multiple clinical trials have established the value of Coronary CT angiography (CCTA) for the evaluation of patients presenting to the ED with chest pain and a low to intermediate risk for acute coronary syndrome (ACS). CCTA can be used to evaluate these patients rapidly, effectively, and with relatively low cost and radiation dose. New research continues to accumulate, and despite much evidence to support its use in the ED setting, at least one recently published study has presented potentially contradictory results. Additionally, newer techniques that enhance the utility of CCTA, such as fractional flow reserve (FFR) and CT perfusion analysis have been developed and are becoming increasingly available. These applications provide important information about the hemodynamic significance of coronary lesions and are potentially useful in the ED setting to aid clinical decision making. This review provides an update on the literature related to the use of CCTA in the ED, including a discussion of emerging advanced cardiac CT applications.

Congenital heart diseases (CHDs) are the most common birth defects, occurring in about 1% of live births. Today, most infants born with CHD live into adulthood. The number of adults with CHD now exceeds the number of children with CHD. As a result, patients with CHD represent a large and steadily growing subpopulation of patients who require specialized diagnostic and therapeutic management. CT is capable of contributing valuable information about congenital abnormalities. We examine the added utility of CT in identifying and assessing CHD in referred patients.