a Goizueta Business School, Emory University, Atlanta, GA 30322, United States b Candler School of Theology and Department of Psychology, Emory University, Atlanta, GA 30322, United States c Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA 30322, United States d Department of Biostatistics, Emory University School of Public Health, Atlanta, GA 30322, United States

Twelve patients with cor triatriatum sinistrum were treated over a 28-year period. Their ages ranged from 1 month to 7.5 years. Congestive heart failure was the most common presentation. Cardiac catheterization was performed on six of the 12 patients and a correct diagnosis of cor triatriatum was made on angiography in only four of the six. Of the remaining six patients, three were diagnosed as having cor triatriatum by echocardiography and three by autopsy. Echocardiography is now considered to be the diagnostic modality of choice in our institution. Seven patients were operated on and five died prior to diagnosis or treatment. Associated cardiac anomalies included persistent left superior vena cava, atrial septal defects, coarctation of the aorta, and total anomalous pulmonary venous drainage. A right atrial, transseptal approach to the common pulmonary chamber and excision of the left atrial membrane was found to be the treatment of choice and was used in six of the seven patients operated on. One patient died in the postoperative period. Thus, cor triatriatum sinistrum, a rare and potentially lethal congential cardiac anomaly, can be diagnosed by echocardiography and successfully treated surgically with a low operative mortality.

Noninvasive exercise testing was used to assess gas exchange in 13 patients age 6-25 yr who had undergone Fontan procedures for tricuspid atresia, five of whom had preexisting Glenn shunts. The results were compared to 28 age- and sex-matched controls. Oxygen saturation was measured by ear oximetry at rest and after exercise. Ventilation, oxygen consumption (VO2), carbon dioxide production (VCO2), and heart rate were measured during progressive exercise. The ventilatory equivalents for oxygen (VE/VO2) and carbon dioxide (VE/VCO2), mixed expired pCO2 (PECO2) end-tidal pCO2 (PETCO2), and dead space to tidal volume ratio (VD/VT) were determined during steady state exercise on a cycle ergometer. Heart rate was higher for VO2 by 15% (p less than 0.02) and ventilation was higher for both VO2 (by 37%, p less than 0.001) and VCO2 (by 27%, p less than 0.002) in the patients than the controls. Mean VE/VO2 was 35.4 +/- 7.8 (SD) compared to 25.8 +/- 3.1 (p less than 0.001) and mean VE/VCO2 was 41.7 +/- 9.0 compared to 31.6 +/- 4.3 (p less than 0.001). Mean PECO2 was 21.4 +/- 4.4 torr with controls at 27.9 +/- 3.8 (p less than 0.001) and mean PETCO2 was 33.0 +/- 5.3 torr compared to 40.0 +/- 3.3 (p less than 0.001). The patients had a mean oxygen saturation of 92 +/- 5% at rest and abnormal saturation after exercise (87 +/- 9, p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Medical treatment has a small role in the management of the symptomatic infant with critical aortic stenosis. Surgical intervention offers the only hope of survival; but even then, the reported mortality has been high in the past. At present, improved techniques and surgical results warrant reassessment of this high-risk lesion, and the experience at Columbia Presbyterian Medical Center with 31 infants with critical aortic stenosis is now reviewed.

Eighteen patients with congenitally corrected transposition of the great arteries had open heart repair for intracardiac associated defects. Fourteen patients (78%) are alive during the follow-up period (mean 4.5 years). Seventeen (94%) of the 18 patients had ventricular septal defect closure, and 12 (66%) insertion of a pulmonary artery conduit. Surgical repair of the tricuspid valve was required in 6 patients (33%) during the first operation and in 3 additional patients during a second operation (total 50%). When hemodynamic overload or cardiac compromise was detected after surgery it was directly related to identifiable residual defects such as atrioventricular valvular insufficiency, residual ventricular septal defect, or pulmonary conduit stenosis. Repeat open heart operation for residual defects was common during the follow-up period (8 of 18 patients, 44%). No patient showed primary systemic or pulmonary ventricular dysfunction during the follow-up period. None of the last 11 patients developed complete heart block. Postoperative intraventricular conduction defects were common and are presumably caused by surgical injury of the bundle branches. Our observations suggest that surgical repair of congenitally corrected transposition of the great arteries can be currently achieved with acceptable risk. Improved knowledge of the precise location of the specialized conduction system resulted in a marked decrease in the incidence of atrioventricular (A-V) block in patients with congenitally corrected transposition of the great arteries undergoing intracardiac repair. In the absence of postoperative residual defects it can be expected that longevity and quality of life will improve considerably, but many of these patients may require a repeat operation.

Two patients with D-transposition of the great arteries (D-TGA) were found to have an unusual form of left ventricular outflow tract obstruction. Both had ball-like accessory mitral valve tissue that partially occluded the outflow tract. In one patient there was an intact septum, while in the other there were ventricular septal defects. The appearances have been described previously, although not in D-TGA. Recognition of accessory mitral valve tissue may allow resection of the tissue at the time of repair of the transposition complex.

The major features of infective endocarditis as found today have been reviewed from the point of view of the radiologist. Surgery has recently emerged with a surprisingly important role in this disease, not only because infective endocarditis is an occasional complication of heart surgery, but also because emergency surgery with prosthetic valve implantation may be life-saving in many patients who have severe aortic and/or mitral valve destruction and intractable heart failure. Novel surgical procedures which have been developed have greatly improved the prognosis in certain otherwise intractable bacterial and fungal infections. In left heart endocarditis the radiologic findings are not usually impressive until valve destruction is so advanced that signs of cardiac failure are produced. Even at this advanced stage, however, the diagnosis may not have been considered clinically. The radiologist aware of infective endocarditis can be important in making the initial diagnosis, in following the course of the patient, and in aiding in selecting the time for surgical intervention should that be necessary. Right heart infective endocarditis is much less common. It is most characteristic of drug addicts but may be seen in many other situations including certain types of congenital heart disease and in patients with depressed immune mechanisms. Since lung infection is the dominant clinical feature and heart murmurs are often absent, the alert radiologist can be the first to suggest this diagnosis in many cases.

technique [51 for delineating areas of damaged myocardium has been developed as an aid in left ventricular resection, A aneurysmectomy, and revascularization.The method utilizes an electrode probe to obtain bipolar electrograms directly from the ventricles at operation.Previous experimental studies demonstrated that consistent and reproducible alterations in the electrograms appeared in and were limited to areas of myocardium which demonstrated acute and chronic ischemic changes on histological study [5].During the last two years bipolar epicardial and endocardia1 ventricular electrograms have been obtained in 23 patients who underwent cardiac surgery for several complications of coronary artery disease. M A T E R I A L A N D METHODA probe electrode (Fig. 1) containing three silver electrode contacts was used in all 23 patients to obtain surface ventricular electrograms by the technique previously described [51.For the last 11 patients, the technique was modified so that three simultaneous bipolar electrograms were obtained while using the probe electrode.Since the contacts of the probe are arranged in a triangular fashion, by means of a junction box, three bipolar electrograms may be obtained.This modification eliminates the possibility of electrograms manifesting deceptively low amplitude as a result of inadvertent placement of a single bipolar electrode in an axis perpendicular to the direction of the electric excitation wave.T h e electrograms were obtained prior to or during cardiopulmonary bypass and were recorded simultaneously with a standard ECG limb lead on a DR-12

Summary 1. In 568 open-heart operations, bacterial endocarditis has occurred in 13 patients. One infection occurred with a ventricular septal defect prosthesis, two with a mitral valve prosthesis, and ten were associated with an aortic valve prosthesis. 2. The clinical course was either acute or chronic. The latter form was often benign and the diagnosis was not established for 2½ to 5 months postoperatively. 3. The causative organism was Staphylococcus epidermidis in 11 of the 13 cases, an organism usually considered nonpathogenic. 4. Four patients have survived this complication and the course of these patients has been presented. 5. The use of therapeutic dosages of antibiotics, specifically the introduction of an effective bactericidal antibiotic against staphylococcus, has eliminated staphylococcus endocarditis as a complication following valve replacement.