Jae K. Oh

Transcatheter aortic-valve replacement with a self-expanding prosthesis.

BACKGROUND We compared transcatheter aortic-valve replacement (TAVR), using a self-expanding transcatheter aortic-valve bioprosthesis, with surgical aortic-valve replacement in patients with severe aortic stenosis and an increased risk of death during surgery. METHODS We recruited patients with severe aortic stenosis who were at increased surgical risk as determined by the heart team at each study center. Risk assessment included the Society of Thoracic Surgeons Predictor Risk of Mortality estimate and consideration of other key risk factors. Eligible patients were randomly assigned in a 1:1 ratio to TAVR with the self-expanding transcatheter valve (TAVR group) or to surgical aortic-valve replacement (surgical group). The primary end point was the rate of death from any cause at 1 year, evaluated with the use of both noninferiority and superiority testing. RESULTS A total of 795 patients underwent randomization at 45 centers in the United States. In the as-treated analysis, the rate of death from any cause at 1 year was significantly lower in the TAVR group than in the surgical group (14.2% vs. 19.1%), with an absolute reduction in risk of 4.9 percentage points (upper boundary of the 95% confidence interval, -0.4; P<0.001 for noninferiority; P = 0.04 for superiority). The results were similar in the intention-to-treat analysis. In a hierarchical testing procedure, TAVR was noninferior with respect to echocardiographic indexes of valve stenosis, functional status, and quality of life. Exploratory analyses suggested a reduction in the rate of major adverse cardiovascular and cerebrovascular events and no increase in the risk of stroke. CONCLUSIONS In patients with severe aortic stenosis who are at increased surgical risk, TAVR with a self-expanding transcatheter aortic-valve bioprosthesis was associated with a significantly higher rate of survival at 1 year than surgical aortic-valve replacement. (Funded by Medtronic; U.S. CoreValve High Risk Study ClinicalTrials.gov number, NCT01240902.).

Transesophageal Echocardiography: Technique, Anatomic Correlations, Implementation, and Clinical Applications

The introduction of transesophageal echocardiography has provided a new acoustic window to the heart and mediastinum. High-quality images of certain cardiovascular structures [left atrial appendage, thoracic aorta, mitral valvular apparatus, and atrial septum] can be obtained readily (average examination, 15 to 20 minutes). In this article, we discuss the technique of image acquisition, image orientation, and anatomic validation. In addition, we describe our experience with the first 100 awake patients who underwent transesophageal echocardiography at our institution. The procedure was well accepted by the patients and associated with no major complications. The clinical indications for this procedure have included thoracic aortic dissection, prosthetic cardiac valve dysfunction, detection of an intracardiac source of embolism, endocarditis, cardiac and paracardiac masses, and mitral regurgitation. Transesophageal echocardiography also proved to be useful in assessment of critically ill patients in whom standard transthoracic echocardiographic images did not provide complete assessment. In these patients (who had extensive chest trauma, had undergone an operation, or were in an intensive-care unit), rapid assessment of the cardiovascular status at the bedside was possible with transesophageal echocardiography. On the basis of our initial experience, we conclude that transesophageal echocardiography complements standard two-dimensional Doppler and color flow examinations and will considerably improve the care of patients with cardiovascular disorders by providing high-quality unique images.

Biplanar transesophageal echocardiography : anatomic correlations, image orientation, and clinical applications

Clinical transesophageal echocardiography is a rapidly expanding diagnostic procedure. Conventional transesophageal endoscopes allow imaging from a single array mounted in the horizontal plane. This article introduces the clinical application of biplanar imaging, which incorporates a second orthogonal longitudinal plane. Our clinical experience with 291 patients who underwent biplanar transesophageal echocardiography is presented. The examination, technique, and resultant anatomic correlations unique to this new examination are discussed and illustrated. The anatomy is displayed in a familiar format comparable to the precordial examination. Biplanar imaging adds substantially to the comprehensive anatomic delineation of certain cardiac structures.

Choice of computed tomography, transesophageal echocardiography, magnetic resonance imaging, and aortography in acute aortic dissection: International Registry of Acute Aortic Dissection (IRAD).

For acute aortic dissection, CT is selected most frequently worldwide as the initial test, followed by TEE. Aortography and MRI are performed much less often. More than two thirds of the patients required ≥2 imaging tests.

Iatrogenic aortic dissection

Given the difference in risk factors, clinical presentation, and outcomes, clinicians should be vigilant for the presence of iatrogenic AD, particularly in those patients with unexplained hemodynamic instability or myocardial ischemia following invasive vascular procedures or CABG.

Association of Painless Acute Aortic Dissection With Increased Mortality

OBJECTIVE To evaluate the clinical characteristics and outcomes of patients with painless acute aortic dissection (AAD). PATIENTS AND METHODS For this study conducted from 1997 to 2001, we searched the International Registry of Acute Aortic Dissection to identify patients with painless AAD (group 1). Their clinical features and in-hospital events were compared with patients who had painful AAD (group 2). RESULTS Of the 977 patients in the database, 63 (6.4%) had painless AAD, and 914 (93.6%) had painful AAD. Patients in group 1 were older than those in group 2 (mean +/- SD age, 66.6 +/- 13.3 vs 61.9 +/- 14.1 years; P = .01). Type A dissection (involving the ascendIng aorta or the arch) was more frequent in group 1 (74.6% vs 60.9%; P = .03). Syncope (33.9% vs 11.7%; P < .001), congestive heart failure (19.7% vs 3.9%; P < .001), and stroke (11.3% vs 4.7%; P = .03) were more frequent presenting signs in group 1. Diabetes (10.2% vs 4.0%; P = .04), aortic aneurysm (29.5% vs 13.1%; P < .001), and prior cardiovascular surgery (48.1% vs 19.7%; P < .001) were also more common in group 1. In-hospital mortality was higher in group 1 (33.3% vs 23.2%; P = .05), especially due to type B dissection (limited to the descending aorta) (43.8% vs 10.4%; P < .001), and the prevalence of aortic rupture was higher among patients with type B dissection in group 1 (18.8% vs 5.9%; P = .04). CONCLUSION Patients with painless AAD had syncope, congestive heart failure, or stroke. Compared with patients who have painful AAD, patients who have painless AAD have higher mortality, especially when AAD is type B.

Mitral valve operation in postinfarction rupture of a papillary muscle: immediate results and long-term follow-up of 22 patients.

The long-term clinical outcome was assessed in 22 patients (15 men and 7 women; mean age, 68 years) who underwent mitral valve replacement or repair for acute mitral regurgitation due to postinfarction rupture of a papillary muscle during the period 1981 through 1990 at the Mayo Clinic. All but three patients underwent operation within the first 3 weeks after acute myocardial infarction. The perioperative mortality was 27%, and the estimated actuarial survival rate at 7 years postoperatively was 47% and 64% for the entire group and for the patients who survived the operation, respectively. The concomitant performance of a coronary artery bypass grafting procedure was the only factor identified that improved both immediate and long-term survival. Patients with a decreased preoperative left ventricular ejection fraction (less than 45%) had somewhat greater short-term and long-term mortality than did those with a left ventricular ejection fraction of 45% or more, but the difference was only of borderline statistical significance. Other factors such as age, sex, severity of coronary artery disease, preoperative existence of congestive heart failure, and timing of the operation in relationship to occurrence of the infarction had no effect on survival. Of the 13 long-term survivors, 10 had significant clinical improvement in comparison with their preoperative state.

Evidence of Impaired Left Ventricular Systolic Function by Doppler Myocardial Imaging in Patients With Systemic Amyloidosis and No Evidence of Cardiac Involvement by Standard Two-Dimensional and Doppler Echocardiography

We examined the potential role of Doppler myocardial imaging for early detection of systolic dysfunction in patients with systemic amyloidosis (AL) but without evidence of cardiac involvement by standard echocardiography. We identified 42 patients without 2-dimensional echocardiographic or Doppler evidence of cardiac involvement. These patients had normal ventricular wall thickness and normal velocity of the medial mitral annulus. Myocardial images were obtained in these patients and in 32 age- and gender-matched healthy controls. Peak longitudinal systolic tissue velocity (sTVI), systolic strain rate (sSR), and systolic strain (sS) were determined for 16 left ventricular segments. Radial and circumferential sSR and sS were also measured. Compared with controls in this group of patients with AL, peak longitudinal sSR (-1.0 +/- 0.2 vs -1.4 +/- 0.2, p <0.001) and peak longitudinal sS (-15.6 +/- 3.3 vs -22.5 +/- 2.0 p <0.001) were significantly decreased. In conclusion, the mean sS from all 6 basal segments, or from all 16 left ventricular segments differentiated patients with AL with normal echocardiography from controls, with similar accuracy for the mean sSR from the 6 basal segments. This distinction was not apparent from peak longitudinal sTVI or from radial or circumferential sSI or sSR.

The Clinical Characteristics, Laboratory Parameters, Electrocardiographic, and Echocardiographic Findings of Reverse or Inverted Takotsubo Cardiomyopathy: Comparison With Mid or Apical Variant

Although takotsubo cardiomyopathy (TTC) typically affects the apical and/or midventricular segments, several recent cases have reported a reverse or inverted variant of TTC. The aim of this study was to investigate the clinical characteristics, laboratory parameters, electrocardiographic, and echocardiographic findings in patients presenting as inverted TTC and compare those parameters to those presenting as mid or apical variant.

The Mechanism of Blood Flow During Closed Chest Cardiac Massage in Humans: Transesophageal Echocardiography Observations

Despite years of research, the mechanism of forward blood flow during closed chest cardiac massage remains controversial. Two theories have been suggested: the cardiac pump theory and the thoracic pump theory. Transesophageal echocardiography offers a new approach for study of the flows and cardiac morphologic features during chest compressions in humans. Case reports are presented to illustrate the use of transesophageal echocardiography during cardiopulmonary resuscitation. The findings included right and left ventricular compression, closure of the mitral valve during compression, opening of the mitral valve during the release phase, and atrioventricular valvular regurgitation during compression, indicating a positive ventricular-to-atrial pressure gradient. These findings suggest that direct cardiac compression was the predominant mechanism of forward blood flow during cardiopulmonary resuscitation in these patients. An understanding of the actual mechanisms involved is necessary if improved cardiopulmonary resuscitative techniques or adjuncts are to be rationally developed for enhancing the outcome of resuscitation.