Cesar J. Herrera

A possible mechanism for neurologic ischemic events in patients with atrial septal aneurysm

Abstract A trial septal aneurysm (ASA) is a congenital malformation of the atrial septum that has been associated, among other conditions, with transient ischemic attacks and strokes. 1–5 The nature of this relation is unclear. Embolic events have been attributed to thrombus formation in or at the base of the aneurysmal sac. 5,6 However, the possibility of an associated functionally patent foramen ovale leading to a paradoxical embolus from a right-to-left shunting also has been suggested. 2–4 To help clarify this issue, we analyzed the morphologic and functional characteristics of the atrial septum in patients with ASA by the use of transesophageal contrast echocardiography.

Comparison of Exercise and Dobutamine Stress Echocardiography in Assessing Mitral Stenosis

Dobutamine elicited similar hemodynamic response to exercise in 20 consecutive patients with mitral stenosis, and significantly altered management in 6 of them (30%). Dobutamine stress echocardiography is a safe and feasible alternative to exercise in patients with mitral stenosis of mild-to-moderate severity and ambiguous symptoms.

Comparison of transesophageal and transthoracic echocardiography for diagnosis of right-sided cardiac lesions

Abstract Two-dimensional transthoracic echocardiography (TTE) is an established method for the evaluation of cardiac or paracardiac structural abnormalities such as tumors, vegetations and thrombi. 1–4 Cardiac structural resolution can be limited with TTE owing to anatomic interference. With transesophageal echocardiography (TEE), regions of the heart previously difficult to visualize are now readily studied. These regions include the vena cavae, right ventricular outflow tract, pulmonic valve and pulmonary trunk. The usefulness of TEE as compared with TTE in assessing right-sided cardiac pathology has not been clearly determined. We compared both techniques with the objectives of studying their diagnostic ability for the evaluation of right-sided cardiac lesions, and comparing data obtained with those from other confirmatory techniques.

Pathologic and angiographic correlations of transesophageal echocardiography in prosthetic heart valve dysfunction

To determine the diagnostic accuracy of transesophageal echocardiography (TEE) in prosthetic valve dysfunction, the pathologic and/or angiographic data from 37 valves were compared with that obtained by transesophageal and transthoracic echocardiography. Of the 21 prostheses with severe regurgitation, TEE identified all 14 mitral, the five aortic, and one of the two tricuspid valves; on the other hand transthoracic echocardiography identified 2 of the 14 mitral, the five aortic, and one of the two tricuspid valves. Of the 10 prostheses with flail cusp(s), nine (90%) were correctly identified by TEE and four (40%) were correctly identified by transthoracic echocardiography. All five prostheses with paravalvular regurgitation were detected through the esophageal window and one detected through the precordial window. TEE was unable to document the two prosthetic aortic stenoses, whereas the transthoracic examination correctly quantified the gradient in one but underestimated it in the other case. Seven patients underwent valve replacement on the basis of the clinical and TEE information alone. In assessing cause, origin, and severity of prosthetic mitral regurgitation, TEE is the method of choice. In selected cases, TEE can avoid angiography and facilitate optimal timing of reoperation. In selected aortic and tricuspid dysfunction, TEE may provide additional morphologic, but limited hemodynamic information.

Value and limitations of transesophageal echocardiography in evaluating prosthetic or bioprosthetic valve dysfunction

Optimal management of patients with prosthetic heart valves requires serial assessment of valve function. The addition of Doppler and color flow techniques to conventional transthoracic echocardiography (TTE) has increased our ability to evaluate prosthetic valve function. However, the sensitivity of TTE remains limited in a number of patients because of suboptimal precordial windows or because of ultrasound interference with the nonbiologic materials composing the prostheses.1–3 Transesophageal echocardiography (TEE) allows excellent imaging resolution of the cardiac anatomy without interposition of thoracic structures. Recently, TEE has been shown to increase the yield of undetected prosthetic valve abnormalities by TTE.4–8 However, most of the TEE information relates to biologic prostheses in the mitral position.5–8 Thus, the purpose of this study was to investigate the diagnostic accuracy of TEE in evaluating mechanical and biologic prostheses in both aortic and mitral positions, and the impact of the TEE information on the clinical outcome.

Atherosclerotic plaque evolution in the descending thoracic aorta in familial hypercholesterolemic patients. A transesophageal echo study.

We explored the concept that transesophageal echocardiography can be used as a tool to detect, characterize, and study plaque morphology in the descending thoracic aorta. The pattern of atherosclerotic plaques in the descending thoracic aorta in familial hypercholesterolemic (FH) patients was evaluated. Additionally, evolution of plaque characteristics as a result of therapy was analyzed. In a randomized prospective protocol, eight FH patients (five men and three women, aged 23 to 65 years [mean +/- SD, 42 +/- 14 years]) receiving standard therapy (n = 3; baseline low-density lipoprotein [LDL] cholesterol, 222 +/- 71 mg/dL, mean +/- SD) or LDL apheresis (n = 5; baseline LDL cholesterol, 262 +/- 51 mg/dL) were studied. Baseline and follow-up (mean, 12 months) transesophageal echocardiographic studies were performed. Measurements obtained were atherosclerotic plaque area (PA), aortic wall area (WA), total arterial area (TAA), and plaque-to-wall area ratio (PWR). LDL cholesterol decreased in both groups. The greatest severity of plaque was detected at 30 to 35 cm from the incisors (approximately 15 to 20 cm from the aortic arch). The smallest plaques were present at the arch and more distal descending aorta. In the control group, TAA, PA, and PWR did not change significantly (P = NS versus baseline). In the LDL-apheresis group, TAA increased (P < .05 versus baseline), PA decreased in three of five patients (P = NS versus baseline), and PWR fell (P < .05 versus baseline).(ABSTRACT TRUNCATED AT 250 WORDS)

VO2 Max and Anaerobic Threshold in Hypertension: A Tissue Doppler Study

Background: Hypertension can impair left ventricular (LV) relaxation causing shortness of breath and reduced exercise capacity, which may affect the clinical evaluation of the symptomatic hypertensive patient. In this study we used tissue Doppler imaging (TDI) to identify correlates of anaerobic threshold (AT) and maximum oxygen uptake (VO2 Max). Our goal was to assess the feasibility of TDI as a surrogate of functional capacity in hypertensive individuals. Methods: We studied subjects without metabolic syndrome and with normal LV function (ejection fraction (EF) >50%) . Traditional echocardiographic variables were obtained before and after a cardiopulmonary exercise test. Systolic (S) and diastolic (E′and A′) myocardial velocities were measured at the basal septal (bs) and posterior (bp) walls. Results: After multivariate analysis, resting E′bp (r =0.56, P < 0.002) and isovolumic relaxation time (IVRT) (r =−0.49, I < 0.03) correlated with VO2 Max, while A Valsalva correlated with AT (r =−0.46, P < 0.03). Peak stress E′/A′bp correlated with age and gender corrected METs (r =−0.63, P < 0.0004) and VO2 Max (r =−0.39, P< 0.04). Conclusions: Resting E′bp and peak stress E′/A′bp correlate with VO2 Max in hypertensive patients. TDI may be an important tool when assessing symptoms in this population.

Novel developments in stress cardiomyopathy: From pathophysiology to prognosis.

Stress cardiomyopathy (SC) is characterized by transient left ventricular (LV) wall motion abnormalities typically involving the apex with preserved basal contractility, chest discomfort, ST-T ischemic changes and elevated cardiac markers with normal or non-flow limiting coronary artery lesions. It represents an important differential diagnosis of Acute Coronary Syndromes caused by atherosclerotic vessel occlusion; most commonly, Tako-tsubo occurs in postmenopausal women after physical or emotional stress. While the exact mechanism of SC remains controversial, various hypotheses have been suggested concerning the vascular, central nervous and endocrine system participation where catecholamines, particularly epinephrine, seem to play a major role. Hormonal, genetic and psychiatric conditions may also define the risk of susceptibility in some groups affected by SC. Long-term survival data are limited with mortality occurring predominantly in the first year after diagnosis usually related to non-cardiac illnesses. Echocardiography promises to become a useful tool to correctly identify SC patients at high risk for complications.

Radiating Chest Pain to the Back

A 69-year-old woman presented to an outside hospital with chest pressure radiating to the back and dyspnea. Computed tomography (CT) of the chest with pulmonary embolism protocol for elevated D-dimer was negative (Figure 1). She had mild Troponin elevation that resolved along with the symptoms, and the patient underwent a stress test to rule out acute coronary syndrome. She developed dyspnea during the test, prompting a chest x-ray, which showed left-sided pleural effusion and mediastinal shift to the right that was not seen on the admission chest x-ray (Figure 2). A thoracentesis demonstrated hemorrhagic fluid. A CT of the chest without contrast showed an intimal flap in the aorta with a centrally displaced calcified atherosclerotic plaque characteristic of aortic dissection that could not be seen in the previous CT with pulmonary embolism protocol (Figure 3). After this, she was transferred to our hospital, where a transthoracic echocardiogram almost 6 hours later showed a type I aortic …