Patricia Mergo

Diffuse Diseases of the Myocardium: MRI-Pathologic Review of Cardiomyopathies With Dilatation

OBJECTIVE In this radiologic-pathologic review of the cardiomyopathies, we present the pertinent imaging findings of diffuse myocardial diseases that are associated with ventricular dilatation, including ischemic cardiomyopathy, nonischemic dilated cardiomyopathy, cardiac sarcoidosis, and iron overload cardiomyopathy. CONCLUSION Correlation of the key radiologic findings with gross and microscopic pathologic features is presented, to provide the reader with a focused and in-depth review of the pathophysiology underlying each entity and the basis for the corresponding imaging characteristics.

Diffuse Diseases of the Myocardium: MRI-Pathologic Review of Nondilated Cardiomyopathies

OBJECTIVE This article will present correlation of the key radiologic findings with gross and microscopic pathology for the characterization of diffuse myocardial diseases using advanced imaging techniques. Our goal is to provide a focused and in-depth review of the pathophysiology underlying each entity and to emphasize the structural basis for the corresponding imaging characteristics. This article is limited to those disorders characterized by ventricular wall thickening without chamber dilatation, including hypertrophic cardiomyopathy, hypertensive cardiomyopathy, and cardiac amyloidosis. CONCLUSION For the characterization of diffuse myocardial diseases using advanced imaging techniques, it is essential to understand the underlying pathologic changes in the heart. With these techniques, such as cardiac MRI, the various cardiomyopathies can be differentiated accurately, which may potentially obviate invasive testing and endomyocardial biopsy.

Emerging Role of Cardiovascular CT and MRI in the Evaluation of Stroke

OBJECTIVE. The purposes of this article are to explore the potential for use of CT angiography and MRI and to highlight data suggestive of their usefulness in specific cardiovascular abnormalities. CONCLUSION. The evaluation of stroke requires comprehensive assessment of potential stroke mechanisms, including cardiac sources. Despite an exhaustive search for secondary causes, the precise cause of many strokes remains unknown (cryptogenic). It is well recognized, however, that some of these potential causes occur as a result of embolism from the heart or great vessels. Thus, echocardiography, in particular transesophageal echocardiography, is instrumental in a careful assessment of cardiac causes in selected individuals. Unfortunately, transesophageal echocardiography is invasive, and some patients may have relative or absolute contraindications. Cardiovascular CT angiography and MRI have growing potential compared with conventional cardiovascular echography.

Cardiac MRI as a diagnostic tool in pulmonary hypertension.

Pulmonary hypertension is characterized by alterations in the viscoelastic properties of the pulmonary arteries, leading to increased pulmonary arterial stiffness and elevated pressures. Early detection and accurate quantification of pulmonary hypertension are limitations to conventional noninvasive imaging and may have therapeutic implications. Cardiac MRI provides important information that can aid the clinician, particularly relating to morphologic right ventricular alterations and quantification of stiffness, as well as providing a novel prognostic framework.

A heart of stone: A case of acute development of cardiac calcification and hemodynamic collapse

Acute cardiac calcification is a clinical entity that may develop over days to months and is usually localized to areas of healed myocardial infarction, cardiac surgery or trauma. We present an unusual case of rapidly developing non-ischemic cardiac calcification in the setting of sepsis and end stage renal disease resulting in acute diastolic dysfunction and cardiac collapse diagnosed by computed tomography (CT) and confirmed by autopsy. We propose that dedicated cardiac CT may provide the most accurate means to detect cardiac calcification.

Radiation Dose in Cardiac Imaging: How Should It Affect Clinical Decisions?

OBJECTIVE The purpose of this article is to discuss whether and how the risks of exposure to ionizing radiation should affect clinical decision making in patients with known or suspected cardiovascular disease. CONCLUSION Although the prevalence of cardiovascular disease and frequency of diagnostic testing has risen dramatically, cardiovascular mortality has declined. Earlier and more accurate detection of cardiovascular disease may play an important role. Concerns regarding excessive radiation exposure from cardiovascular imaging have been raised. Efforts to reduce exposure have included selection of appropriate patients for cardiovascular testing, technologic advances, educational resources, and a directed patient-centered approach to testing.

Assessing the available techniques for testing myocardial viability: what does the future hold?

Left ventricular dysfunction in the setting of severe coronary artery disease poses a major diagnostic and therapeutic dilemma. While this clinical scenario is generally associated with poor outcomes, some but not all patients benefit from coronary revascularization. For example, patients with severe, transmural myocardial infarctions may derive little or no functional benefit from revascularization, as the underlying myocardium is irreversibly scarred. Furthermore, these patients may be exposed to high procedural risks with a low likelihood of deriving any perceivable benefit. Conversely, hibernating myocardium reflects a substrate whereby the nonfunctioning myocytes are chronically ischemic but may be viable. Existing data are somewhat inconclusive with regard to the benefits of performing viability testing in patients with ischemic cardiomyopathy. While this testing may predict regional and global functional myocardial recovery, the ability of viability studies to predict survival and prognosis remains unproven in prospective studies to date. Yet, viability testing may still be a valuable tool to guide therapeutic options in selected patients. A variety of noninvasive viability tests are available and newer technologies, such as PET and cardiac MRI, are likely to advance the scientific field in years to come.

Modern advances in cardiovascular imaging: cardiac computed tomography and cardiovascular MRI in pericardial disease

The pericardium is characterized by a two-layer sac that surrounds the heart and provides an enclosed, lubricated space. Diseases of the pericardium may occur due to active inflammation, scar, calcification or effusion. While clinical, ECG and hemodynamic evaluation have been the established methods for the diagnosis of pericardial disease, advances in cardiac computed tomography and cardiovascular MRI provide complementary tools for diagnostic, prognostic and therapeutic assessment.

Advances of cardiovascular MRI in hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a genetic disease characterized by abnormal myocardial hypertrophy, which can lead to a wide clinical spectrum, including sudden cardiac death and heart failure. Cardiac MRI has a significant role in establishing the diagnosis of HCM. In the three principal management issues related to HCM; testing of family members of affected individuals; assessing the risk of sudden cardiac death from lethal ventricular arrhythmias; and selection of appropriate treatments for left ventricular outflow obstruction, cardiac MRI has established or emerging roles.

Use of cardiac magnetic resonance imaging for alcohol septal ablation in hypertrophic obstructive cardiomyopathy

Abstract This is a report of a 58-year-old man with severe hypertrophic obstructive cardiomyopathy who underwent alcohol septal ablation to relieve symptoms due to severe left ventricular outflow obstruction. Cardiac magnetic resonance was performed before and after the procedure. This case highlights the potential use of cardiac magnetic resonance imaging in the surgical planning of alcohol septal ablation as well as following the procedure to assess for complications and morphological changes.