Scott Stewart

Echocardiography in the Diagnosis of Idiopathic Hypertrophic Subaortic Stenosis Co-existing With Aortic Valve Disease

Echocardiographic studies demonstrated the presence of co-existing idiopathic hypertrophic subaortic stenosis (IHSS) in six patients with aortic valve disease (four calcific aortic stenosis, two pure aortic incompetence). The characteristics of IHSS were a narrow left ventricular outflow tract, a systolic anterior movement of the mitral valve (SAM), and asymmetric ventricular septal hypertrophy. Large SAMs were observed in two patients with pure aortic incompetence and one with aortic stenosis. Relatively small, inconstant, and often incomplete SAMs were noted in the remaining three patients with aortic stenosis. In contrast to isolated IHSS, the small SAMs observed in this group did not become prominent with the Valsalva maneuver or amyl nitrite inhalation. These features may be related to the afterload provided by the fixed, distal stenosis. Echocardiographic evidence of aortic valve disease was present in all patients. Clinically, co-existence of IHSS was not suspected in five patients. Associated IHSS was established using provocative measures during cardiac catheterization in three cases, while in the remainder it was substantiated at surgery. Three of four patients who underwent myotomy/myectomy concomitant with aortic valve replacement survived and postoperative echocardiographic studies revealed complete absence of SAMs in two of them. Echocardiography appears to be useful in the diagnosis of associated IHSS in the presence of aortic valve disease.

The Mechanisms and Management of Noncardiogenic Pulmonary Edema following Cardiopulmonary Bypass

Cardiac surgeons have become more cognizant of the syndrome of noncardiogenic pulmonary edema after cardiopulmonary bypass. Although this syndrome is rare, its occurrence can be catastrophic. This article reviews the current understanding of several factors that have been implicated in the cause of this syndrome and discusses the various options for management of the problem once it has arisen.

Early and Late Results of Repair of Partial Anomalous Pulmonary Venous Connection to the Superior Vena Cava with a Pericardial Baffle

The early and late results of repair of partial anomalous pulmonary venous connection to the superior vena cava with a simple pericardial baffle without enlargement of the superior vena cava were examined. Fifteen consecutive patients received operations between 1973 and 1983, and all survived. They have been followed for a mean of 6 years and a minimum of 2 years. Nodal rhythm and atrial dysrhythmias were present in 6 patients (40%) early after operation. However, every patient resumed normal sinus rhythm prior to hospital discharge except 1 adult who remained in the preoperative rhythm of atrial flutter-fibrillation. No patient has clinical evidence of a residual atrial level shunt or superior vena cava obstruction. All have received an excellent clinical result, and none, except the patient in chronic atrial fibrillation, require cardiac medication. These results are comparable or superior to those obtained with more intricate procedures that use either complex atrial flaps or translocation of the superior vena cava to the atrial appendage.

Superior Sternal Cleft: Repair in the Newborn

Superior sternal cleft is a rare congenital anomaly that should be repaired in the newborn while the bony thorax is still compliant. A method of approximating the U-shaped sternal defect that is applicable to the majority of patients seen as newborns is described.

Placement of the Sutureless Epicardial Pacemaker Lead by the Subxiphoid Approach

Abstract A transmediastinal approach to the heart to apply epicardial pacing leads has not been used in most clinics because the limited exposure makes positioning of the standard lead system difficult. The new sutureless epicardial lead can be easily applied through the subxiphoid approach using local anesthesia.

The Nuts and Bolts of Sternal Dehiscence

An eight-year experience (11 patients) with the Knodt rod compression system for sternal reclosure is presented. The system provides a simple, rapid, and safe method for sternal fixation after dehiscence.

Echocardiography of the intra-atrial baffle in dextro-transposition of the great vessels.

Twelve patients with dextro-transposition of the great vessels (age eight months to four years) were studied by echocardiography following Mustards procedure. Nine of them had also been studied preoperatively. Postoperatively all patients demonstrated structural echoes in the atrial cavity behind the pulmonary root. In ten, the motion pattern generally resembled that of a stenotic atrioventricular valve iwth a sharp anterior movement followed by flattening in diastole and rapid posterior excursion in systole. The maximum amplitude of motion ranged from 4 to 9 mm (average 6.6 mm). In the remaining two cases, the anterior diastolic movement was attenuated. Similar moving, linear echoes with larger amplitudes of motion (10-14 mm) were observed behind the tricuspid valve in four patients while poorly moving, multiple or thick conglomerate echoes (2-11 mm wide) were detected in seven cases. Echocardiographic contrast studies performed by injecting indocyanine green via catheters placed on either side of the intra-atrial baffle identified it as the source of these echoes. Following operation, coarse diastolic undulations of the mitral valve (ten cases) and the tricuspid valve (nine cases) were noted. Also, fine flutter of both atrioventricular valves, not present before, appeared after operation in three patients. These findings may be related to the altered pathway of blood flow and turbulence resulting from the insertion of the baffle in the atria. Echocardiography appears useful in delineating the character and movement pattern of the intra-atrial baffle and this may have potential in evaluating its long-term functional status.

Extended Aortoplasty to Relieve Supravalvular Aortic Stenosis

An extended aortoplasty was used to relieve severe supravalvular aortic stenosis in 5 patients whose preoperative left ventricular-aortic gradient ranged from 85 to 140 mm Hg (median, 120 mm Hg). The stenotic ring above the commissures was divided in two places by an inverted U incision extending into the right and noncoronary sinuses. A distal vertical incision in the ascending aorta converted this into an inverted Y. The ridge above the left coronary sinus was excised. The aortic incision was repaired with an inverted Y-shaped Dacron gusset. The postoperative gradient ranged from 0 to 30 mm Hg (median, 15 mm Hg). The extended aortoplasty provides excellent relief of supravalvular aortic stenosis and, in addition, restores the aortic root geometry to a much more anatomical configuration than is achieved with the simple patch technique.

The Determinants of Survival Following Reoperation on Prosthetic Cardiac Valves

In an effort to identify the determinants of survival following reoperation on patients with prosthetic cardiac valves, the experience with a group of 33 patients at the University of Rochester Medical Center was reviewed. The survival rate was 58% (19/33). Survival was not related to the valve involved, the age of the patient, or the technical hazards of a second cardiac operation. Ten (77%) of the 13 patients in New York Heart Association (NYHA) Functional Class II survived compared with 8 (40%) of the 20 in Class III or IV. The survival rate for patients with a paravalvular fistula was 79% (11/14); with valve dysfunction, 50% (6/12); and with prosthetic valve infection, 29% (2/7). The determinants of survival seem to be similar to those for primary operation (i. e., NYHA patient classification and indication for operation) and less related to the potential operative complications of a reoperation.

Transthoracic and transesophageal echocardiographic sizing of the aortic annulus to determine prosthesis size

To assess the accuracy of 2-dimensional echocardiography versus transesophageal echocardiography (TEE) in predicting aortic annulus diameter, and to determine which part of the cardiac cycle should be used for measuring the size of the aortic valve prosthesis in patients undergoing aortic valve replacement, the aortic annulus was measured retrospectively in a blinded fashion in a group of 94 patients who had undergone aortic valve replacement: 66 had preoperative transthoracic echocardiography (TTE), 69 had intraoperative TEE, and 41 had both. Accuracy of measurements was calculated by the mean biases (differences between annular size by echo and actual valve size chosen by intraoperative mechanical sizing of the aortic annulus). TTE was compared with TEE and end-diastolic (ED) measurements with end-systolic (ES) measurements. The mean biases +/- SD were -1.7 +/- 3.4 mm by TTE-ES versus -0.9 +/- 3.5 mm by TEE-ES measurements (p = NS), and +0.03 +/- 3 mm by TTE-ED versus +0.5 +/- 2.8 mm by TEE-ED (p = NS). Examination of the magnitudes of the biases gave the same result. ED measurements were found to have a smaller amount of bias than ES measurements, both by TTE and by TEE: -1.7 +/- 3.4 mm by TTE-ES versus +0.03 +/- 3 mm by TTE-ED (p = 0.0001) and -0.9 +/- 3.5 mm by TEE-ES versus +0.5 +/- 2.8 mm by TEE-ED (p = 0.0001). Examination of the magnitudes of the biases also gave the same result.(ABSTRACT TRUNCATED AT 250 WORDS)