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Dive into the research topics where Matthew E. Schwinger is active.

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Featured researches published by Matthew E. Schwinger.


Journal of the American College of Cardiology | 1991

Transesophageal echocardiography is superior to transthoracic echocardiography in the diagnosis of sinus venosus atrial septal defect.

Itzhak Kronzon; Paul A. Tunick; Robin S. Freedberg; Naresh Trehan; Barry P. Rosenzweig; Matthew E. Schwinger

The purpose of this study was to compare transthoracic and transesophageal echocardiography in the diagnosis of various types of atrial septal defects. Forty-one adult patients with the clinical diagnosis of atrial septal defect were studied by transthoracic and transesophageal echocardiography (30 women, 11 men; 18 to 81 years of age). Transthoracic echocardiography demonstrated the atrial septal defect in 33 patients (secundum type in 28, primum type in 3 and sinus venosus type in 2). Transesophageal echocardiography demonstrated the defect in all 41 patients. Thus, in 8 (20%) of 41 patients the atrial septal defect was demonstrated by transesophageal and not by transthoracic echocardiography. Six of the eight had a sinus venosus type atrial septal defect; the other two patients had a secundum atrial septal defect (one of these two had a technically poor transthoracic echocardiogram and the other had a small atrial septal defect). Transthoracic echocardiography, therefore, failed to demonstrate the sinus venosus defect in six (75%) of eight patients. An anomalous venous connection associated with the sinus venosus defect was visualized by transesophageal echocardiography in seven of the eight patients but was not seen on transthoracic echocardiography in any patient. Sinus venosus type atrial septal defects are frequently not visualized in adults by conventional transthoracic echocardiography. Transesophageal echocardiography is recommended when an atrial septal defect is clinically suspected but cannot be visualized by transthoracic echocardiography.


Journal of the American College of Cardiology | 1990

Transesophageal echocardiography to detect atrial clots in candidates for percutaneous transseptal mitral balloon valvuloplasty

Itzhak Kronzon; Paul A. Tunick; Ephraim Glassman; James Slater; Matthew E. Schwinger; Robin S. Freedberg

Left atrial thrombi are common in patients with mitral stenosis. When percutaneous balloon mitral valvuloplasty is performed on such patients, there is a potential risk of thrombus dislodgment and embolization. In this study conventional transthoracic echocardiography and transesophageal echocardiography were performed for percutaneous balloon mitral valvuloplasty on 19 consecutive candidates (6 men, 13 women, 23 to 81 years old). In five patients (26%), transesophageal echocardiography revealed a left atrial thrombus; in only one of these was there a suspicion of left atrial thrombus on transthoracic echocardiography. Balloon mitral valvuloplasty was canceled in four of the five patients. Three underwent mitral valve surgery that confirmed the echocardiographic findings. Transesophageal echocardiography is better than conventional transthoracic echocardiography in detecting left atrial clots in candidates for balloon mitral valvuloplasty. Because of the potential risk of embolization, transesophageal echocardiography is recommended in all candidates for balloon mitral valvuloplasty.


American Heart Journal | 1990

The anatomy of the interatrial septum: A transesophageal echocardiographic study

Matthew E. Schwinger; Aaron J. Gindea; Robin S. Freedberg; Itzhak Kronzon

Transesophageal echocardiography provides a unique view of the IAS. We reviewed results of 119 transesophageal studies (1) to study the detailed anatomy of the IAS, and (2) to determine the thickness of the IAS at different times during the cardiac cycle, (3) the effect of age, and (4) the thickness of the IAS in relation to various disease states. From the transesophageal view the IAS extends from the right posteriorly toward the left and anteriorly. The more inferior aspect of the septum courses in a more direct posteroanterior direction and is more difficult to accurately visualize. The IAS is thickest peripherally and gradually narrows toward the more centrally located fossa ovalis. A region of constant thickness is frequently present between the most peripheral aspect of the IAS and the fossa ovalis. We standardized the measurement of the thickness of the septum by measuring it only at this region of constant thickness in the plane that visualized the fossa ovalis. The mean thickness at this point was 6 +/- 2 mm. The thickness correlated weakly with the age of the patient. These results agree with previously published autopsy findings. Thickness was not affected by the presence of significant disease of the atrioventricular valves, atrial fibrillation, or an atrial septal defect. However, the thickness increased to 7 +/- 2 mm with atrial contraction during sinus rhythm (p less than 0.0001). The mean thickness of the septum primum covering the fossa ovalis was 1.8 +/- 0.7 mm.(ABSTRACT TRUNCATED AT 250 WORDS)


Journal of The American Society of Echocardiography | 1989

Transesophageal Echocardiography During Percutaneous Mitral Valvuloplasty

Itzhak Kronzon; Paul A. Tunick; Matthew E. Schwinger; James Slater; Ephraim Glassman

Transesophageal echocardiography was performed during mitral balloon valvuloplasty. It provided valuable information about the position of the transseptal needle, wires, and balloon catheter throughout the procedure, and it helped in the immediate evaluation of its results. Transesophageal echocardiography was well tolerated and there were no complications.


Journal of The American Society of Echocardiography | 1990

Dynamic Left Ventricular Outflow Obstruction After Aortic Valve Replacement: A Doppler Echocardiographic Study

Matthew E. Schwinger; Francis O'Brien; Robin S. Freedberg; Itzhak Kronzon

An 81-year-old woman with severe symptomatic aortic stenosis underwent aortic valve replacement. The postoperative course was complicated by new subvalvular left ventricular outflow tract obstruction created by systolic anterior motion of the anterior mitral leaflet. The condition was recognized by echocardiography and was successfully treated medically.


Journal of The American Society of Echocardiography | 1990

Echocardiographic and Hemodynamic Characteristics of Atrial Septal Defects Created by Percutaneous Valvuloplasty

Itzhak Kronzon; Paul A. Tunick; Andrew Goldfarb; Robin S. Freedberg; Larry Chinitz; James Slater; Matthew E. Schwinger; Aaron J. Gindea; Ephraim Glassman; Werner G. Daniel

Twenty-nine patients were studied by pulsed, continuous wave, and color Doppler before and after percutaneous transseptal valvuloplasty. New atrial septal defects were detected in 14 patients, and the patients were monitored for up to 320 days after the procedure. The diameter of the defect, best evaluated by the transesophageal approach, was 3 to 15 mm. A narrow, high velocity (1.4 to 3.1 meters per second) left-to-right shunt jet was detected in 13 of 14 patients. The shunt jet was continuous in nine of 14 patients, late systolic-holodiastolic in four patients, and bidirectional in one patient. Cardiac catheterization in nine patients confirmed the Doppler findings and demonstrated a peak pressure gradient of 10 to 32 mm Hg between the left and right atria. Oximetry revealed a calculated pulmonary to systemic flow ratio ranging from 2.3:1 in the patient with the largest atrial septal defect by echocardiography to 1:1 (no oxygen saturation step-up) in the patient with the smallest atrial septal defect. In the three patients who underwent cardiac surgery, the operative findings confirmed those of echocardiography. We concluded that atrial septal defects are common after transseptal valvuloplasty. Usually, their relatively small size and the underlying valvular disease that produces high left atrial pressure are responsible for the high pressure gradient between the left and right atria. This results in the high velocity and continuous shunt jet detected by Doppler echocardiography.


American Heart Journal | 1990

Clinical evaluation of high-frequency (ultrasonic) mechanical débridement in the surgical treatment of calcific aortic stenosis

Matthew E. Schwinger; Stephen B. Colvin; Susan Harty; Helen D. Feiner; Lynne Opitz; Itzhak Kronzon

Repair of aortic valve stenosis due to calcific degeneration may lead to hemodynamic and clinical improvement without the problems inherent with prosthetic valves. We have evaluated the use of a device capable of débriding calcium, the Cavitron ultrasonic aspirator (CUSA), as an adjunct to mechanical débridement in the repair of calcific aortic stenosis. Ten patients (five women), ages 63 to 83 years, were studied by M-mode, two-dimensional, and Doppler echocardiography before and an average of 26 (range 3 to 124) days after this procedure. The degree of calcification of the valve cusps was clearly reduced. The maximal cusp excursion increased from 0.7 +/- 0.1 cm preoperatively to 1.5 +/- 0.4 cm postoperatively (p = 0.006). The peak aortic gradient fell from 80 +/- 36 mm Hg to 28 +/- 10 mm Hg (p = 0.0007). The mean aortic gradient fell from 53 +/- 20 mm Hg to 16 +/- 5 mm Hg (p less than 0.0001). Aortic valve area calculated by the continuity equation increased from 0.6 + 0.2 cm2 to 1.6 +/- 0.6 cm2 (p = 0.0009). No patient had more than mild aortic insufficiency preoperatively. Postoperatively, color Doppler flow mapping revealed severe aortic insufficiency in two patients. Seven patients had further echocardiographic evaluation 99 (range 33 to 196) days after the procedure. These studies revealed the development of severe aortic insufficiency in an additional four patients. Four patients with severe symptomatic aortic insufficiency eventually underwent aortic valve replacement. Pathology revealed scarring and retraction of the aortic cusps. Widening of the commissures was responsible for the severe aortic insufficiency.(ABSTRACT TRUNCATED AT 250 WORDS)


American Heart Journal | 1989

Dehiscence of a Carpentier mitral ring: diagnosis by transesophageal echocardiography.

Aaron J. Gindea; Matthew E. Schwinger; Robin S. Freedberg; Stephen B. Colvin; Itzhak Kronzon

We describe a patient with a long-standing dehiscence of a Carpentier ring and severe mitral insufficiency. The nature of the abnormality, which was suggested by transthoracic echocardiography, was definitively diagnosed by transesophageal echocardiography and was confirmed by surgery


American Heart Journal | 1989

Right atrial papillary fibroelastoma: Diagnosis by transthoracic and transesophageal echocardiography and percutaneous transvenous biopsy

Matthew E. Schwinger; Edward S. Katz; Heidrun Rotterdam; James Slater; Edwin C. Weiss; Itzhak Kronzon


American Heart Journal | 1990

Vegetations on endocardial surfaces struck by regurgitant jets: Diagnosis by transesophageal echocardiography

Matthew E. Schwinger; Paul A. Tunick; Robin S. Freedberg; Itzhak Kronzon

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