Transcranial Doppler Ultrasound in the Current Era of Carotid Artery Stenting.

Since its introduction in 1982, transcranial Doppler ultrasound (TCD) has become an important diagnostic and monitoring tool and its usefulness has been well established in many clinical applications. In carotid artery stenting (CAS), TCD has mostly been reserved for the optimization of emboli protection devices. Currently, with increasing use of proximal protection systems resembling surgical clamps, TCD has become invaluable in providing the operator an insight into a patient's cerebral hemodynamic status. Additionally, in selected patients, adverse peri- or post-procedural cerebral outcomes may even be predicted allowing the operator to adjust the therapeutic strategy. This review summarizes the current knowledge regarding the use of TCD in patients undergoing CAS and suggests potential directions of future research.

Poor correlation of estimated pulmonary artery systolic pressure between echocardiography and right heart catheterization in patients awaiting cardiac transplantation: results from the clinical arena.

BACKGROUND: Pulmonary arterial pressure measurement is an integral part of the pre-heart transplant evaluation. In the clinical arena, the correlation and agreement between pulmonary artery systolic pressure (PASP) measured by Doppler echocardiography versus catheterization in pre-heart transplant patients has not been studied. METHODS: Data on all patients evaluated for heart transplantation at our program between 2003 and 2005 (n = 176) were retrospectively reviewed. Patients with both transthoracic echocardiography (with interpretable images) and right heart catheterization performed were included (n = 108; mean time difference, 2.2 days; median, 2 days). The tricuspid valve regurgitant jet was identified by color flow Doppler and jet maximum velocity was measured by continuous wave Doppler. The PASP was estimated by using the modified Bernoulli equation and adding right atrial pressure. We correlated echocardiographically estimated PASP with that measured by right heart catheterization. RESULTS: Mean estimated PASP by echocardiography was 46.6 +/- 13.7 mmHg versus 44.8 +/- 17.9 mmHg by right heart catheterization (P = NS). However, the correlation between echocardiographic and measured PASP was poor (r = 0.49, P < .001). The correlation was poor in both ischemic and nonischemic cardiomyopathy. CONCLUSION: Among patients referred for heart transplant evaluation, there is poor agreement and correlation between echocardiographically estimated PASP and values obtained by right heart catheterization. Furthermore, echocardiographically obtained estimates of PASP should not be exclusively relied upon to exclude heart transplant recipient candidates.

Transesophageal echocardiographic evaluation of coronary arteries for stenosis in the elderly patient.

This article documents the ability of transesophageal echocardiography to provide adequate images and clinically relevant information about the coronary anatomy of the elderly patient. Transesophageal echocardiography is commonly used to assess elderly patients who suffer cerebral vascular accidents. It is important to evaluate not only for the usually suspected causes of a cardiac source of emboli but also for direct and indirect evidence of coronary artery disease--the leading cause of death in the elderly stroke patient. Because atherosclerotic cardiovascular diseases identified in one vascular bed are prone to universally involve the other vascular territories to some degree, it is not surprising that the coronary arteries are often stenotic. As a sudden event with catastrophic symptoms, a stroke is commonly the first vascular event the elderly patient experiences. Depending on the degree of recovery, physical limitations may contribute to the lack of symptoms from coexistent peripheral or coronary artery disease. Transesophageal echocardiography may be the first, or only, coronary evaluation for high-risk elderly patients.

Noninvasive right and left heart catheterization: taking the echo lab beyond an image-only laboratory.

The assessment of cardiovascular hemodynamics is an extremely important component of managing patients with cardiac diseases. For years, this has been accomplished primarily through the use of right and left heart catheters placed within the cardiac chambers. Since this is an invasive technique, it should only be used when necessary; patient discomfort, infections, and overall risks for physicians would be reduced if noninvasive methods were utilized when available. Echocardiography (echo) provides the greatest ability to determine cardiovascular hemodynamics noninvasively, but requires the utmost precision and care to avoid misinterpretation. When used correctly, echocardiographic modalities provide an even greater assessment of the cardiac patient than invasive techniques. A safer and more comprehensive interpretation is available, and thus, echo should be considered the modality of choice-the new gold standard.

Transesophageal echocardiographic assessment of coronary stenosis: a decade of experience.

Coronary artery imaging is routinely obtained invasively at cardiac catheterization through coronary angiography. This remains the gold standard, but with advances in ultrasound technology, electron beam computed tomography, and magnetic resonance imaging, newer noninvasive methodologies are achieving greater success at imaging the coronary anatomy. This review is meant to highlight the important accomplishments from transesophageal echocardiographic (TEE) investigations that have studied the coronary arteries. The specific technique for optimally imaging the coronaries with high frequency transducers, color and conventional Doppler, in addition to contrast-enhanced methods, will be analyzed. Importantly, this article serves as a reminder to echocardiographers and cardiologists that excellent, clinically relevant information of the coronary arteries can be obtained routinely during TEE. This technique is part of the trend noted by the other authors in this special edition; that is, echocardiography is becoming the gold standard of the new millennium for many diagnostic areas, even coronary angiography.

Diagnostic tools and management strategies for coronary artery disease in patients with end-stage renal disease.

Patients with renal disease often have coexistent coronary artery disease (CAD). The 5-year survival rates are < 50% and cardiovascular disease accounts for nearly half of the deaths in patients with end-stage renal disease (ESRD) on maintenance dialysis. Renal disease is often caused by hypertension or diabetes mellitus, both very strong risk factors for the development of CAD. Other patients develop hypertension after the onset of their renal disease. These coexistent diseases partially contribute to the increased incidence of CAD in the renal patient. Managing physicians must maintain a high index of suspicion and interpret the results of diagnostic studies with this high pretest probability in mind. Consideration should be given for screening for the presence of ischemic heart disease in patients with ESRD and no symptoms, especially if being considered as renal transplant recipients. It remains most important to adequately treat the associated risk factors and specifically, aggressively control the blood pressure. This report discusses the known and suspected reasons for the highly associated coexistent CAD, methods for diagnosing and risk-stratifying CAD, and renal-specific guidelines for appropriate treatment.

Role of echocardiography in the diagnosis and management of heart failure in the elderly.

Heart failure is the most common cause of cardiovascular hospitalization in older adults in the United States. This disease is common, disabling, and commonly fatal, especially in the elderly population. Hypertension and coronary artery disease are the leading causes of heart failure. A precise diagnosis of the cardiac abnormality is paramount for adequate treatment, and echocardiography offers the most comprehensive, noninvasive evaluation. With an organized approach using two-dimensional and Doppler echocardiography, the systolic and diastolic left ventricular performance can be determined; the cardiac output, pulmonary artery, and ventricular filling pressures can be estimated; and surgically correctable valve disease can be identified. The response and success of treatment also may be monitored by the judicious use of echocardiography.

Fungal endocarditis at the aortotomy site after aortic valve replacement.

This brief report presents a patient with fungal endocarditis involving the suture location in the ascending aorta after aortotomy to replace a stenotic aortic valve. It emphasizes the importance of expanding the diagnostic investigation for endocarditis beyond the prosthesis, which was normal in this case. It also reiterates the value of transesophageal echocardiography during the evaluation of prosthetic valves and reminds the echocardiographer to visualize the aortotomy site carefully.

Current knowledge and significance of coronary artery ectasia: a chronologic review of the literature, recommendations for treatment, possible etiologies, and future considerations.

Coronary artery ectasia is the abnormal enlargement of the coronary artery. The prognosis, treatment, and etiology of this disease remain an enigma. There is some evidence to suggest that the incidence of ectasia is increasing, and therefore understanding of this entity needs to improve. This article reviews the current literature on coronary artery ectasia and summarizes the findings. A treatment plan that targets each of the suggested clinical complications is provided. Using multiple indirect observations and current understanding of endothelium-derived relaxation factor, a possible etiology that implicates overstimulation of endogenous nitric oxide is provided. Current literature suggests that ectatic coronary arteries, even without the presence of coronary stenosis, are subject to thrombus formation, vasospasm, and spontaneous dissection. Newer subgroups of ectasia are arising with the use of multiple interventional devices to dilate coronary artery stenosis. By design, these destroy the media of the coronary artery, and it is not clear whether these "iatrogenic" ectatic arteries are subject to the same complications as "idiopathic" coronary artery ectasia. Further investigation is necessary to help define the benefit of the proposed treatment regimen, to clarify the prognosis of these newer groups of "iatrogenic" ectasia, and to confirm or disprove the hypothesis targeting nitric oxide as an etiologic factor.

Who is interpreting nuclear cardiology studies in the United States, and what are the requirements for privileges? A national survey of institutional policies from 80 major medical centers.

BACKGROUND: This survey was conducted to determine the guidelines used by major medical centers in the United States for obtaining hospital privileges to interpret nuclear cardiology studies. The American College of Cardiology (ACC) and the American Society of Nuclear Cardiology (ASNC) have established guidelines to help maintain an adequate level of proficiency in the practice of nuclear cardiology. These guidelines were published only recently, and many hospitals have adopted different processes to obtain these privileges. It is likely that a marked difference among institutions exists. METHODS AND RESULTS: The survey was conducted predominantly by mailings with additional telephone communications if more information was needed. Chiefs of cardiovascular medicine sections were contacted to provide information concerning the policy of granting nuclear cardiology privileges at his or her institution. The responses were tabulated in four categories and the responders were asked to comment on whether they agreed or disagreed with their own university's policy. Of 80 responses (68%) from 121 institutions, cardiologists were involved in reading these studies in 62 (78%) and radiologists were the sole interpreters in 18 (22%). ACC or ASNC guidelines were strictly followed at 48 sites (60%). Eight (10%) and 6 (8%) of these institutions mandated a minimum requirement of, respectively, 12 and 6 months of additional training in nuclear cardiology. Ten (13%) of the cardiologists surveyed disagreed with their own institution's policies, primarily noting that the ACC and ASNC guidelines were more appropriate. CONCLUSION: The recently established ACC/ASNC guidelines clearly have had an impact on the practice of attaining privileges in nuclear cardiology and are the most commonly quoted criteria used by institutions in the United States to assess competence in nuclear cardiology.

Left ventricular pseudoaneurysm.

Cardiorrhexis, or rupture of the myocardium, is an uncommon event after acute myocardial infarction. It has serious consequences such as acute hemopericardium, cardiac tamponade, and sudden death. If the rupture remains enclosed by surrounding adhesions or an intact visceral pericardium, a pseudoaneurysm may develop. We describe a rather typical presentation of a pseudoaneursym of the left ventricle with resultant congestive heart failure after a silent myocardial infarction, and we point out the utility of prompt ultrasound examination in this clinical setting.