Coronary artery fistula in the pediatric age group: a 19-year institutional experience.

Ten patients with coronary artery fistulae were identified from records at Columbus Children's Hospital between 1974 and 1993. Clinical presentations of patients were quite variable, from 1 day to 20 years of age. Symptoms ranged from none to severe cardiorespiratory failure requiring extracorporeal membrane oxygenation. Long term follow-up revealed one sudden death and one spontaneous closure of the fistula. This lesion should be ruled out in patients who present as extracorporeal membrane oxygenation candidates. Patients with mild forms of this lesion may be followed up medically if the left to right shunt is inconsequential, because spontaneous closure is a possibility. Because of the risk of sudden death, close long-term follow-up is mandatory even for operated patients, and antiplatelet therapy should be considered for these patients.

Results of operation for aortic valve stenosis in infants, children, and adolescents.

Surgical procedures for aortic valve stenosis may be considered either corrective or palliative. During a 22-year period from 1962 to 1984, 120 patients required operation for aortic valve stenosis. The operations done included 117 valvotomies and three initial valve replacements. Six patients, five infants and a 7-year-old girl, died at operation. The remaining 114 patients were followed up for 1 to 23 years (mean 8.7 years). Twenty-six patients (23%) required a second operation 1 to 15 years (mean 6.8 years) after initial valvotomy. Six patients (5%) required a third operation 3 months to 8 years (mean 4.4 years) after the second operation. Eighteen of the 26 patients (69%) having second operations required valve replacement. All third operations were valve replacements. No perioperative deaths occurred at the second and third operations. There were four sudden late deaths (3.5%). Eighty-four of the 114 patients (74%) followed up for 1 to 23 years (mean 7.7 years) have had a satisfactory result from initial valvotomy, being free of symptoms and major events (stroke, endocarditis, sudden death), and have not required reoperation. Fifty-nine percent of a subgroup of 22 patients followed up for a mean of 17.7 years have had a satisfactory result from initial valvotomy.

Delayed sternal closure after cardiac surgery.

Fifty-seven patients undergoing various cardiac operations were managed with delayed sternal closure because of ongoing mediastinal hemorrhage or extreme cardiac dilatation. This strategy facilitated rapid access to the mediastinum for evacuation of clot when the risk of tamponade from hemorrhage was deemed great. When sternal closure over a dilated and edematous heart caused hemodynamically significant cardiac compression, wound closure without sternal reapproximation facilitated hemodynamic stability. Postoperative correction of hemodynamic and hemostatic functions allowed delayed sternal closure to be done a mean of 2.8 days later. Thirty-eight patients survived to leave the hospital. Recognized complications of delayed sternal closure included superficial wound infection (3 patients), sternal osteomyelitis (1 patient), and fatal mediastinal infection (1 patient). Delayed sternal closure may be beneficial in selected patients. Morbidity and mortality related to this technique have proved acceptable in this high-risk group.

Evidence for progression from mild to severe mitral regurgitation in mitral valve prolapse.

Little information is available concerning the progression of mild to severe mitral regurgitation (MR) in patients with mitral valve prolapse (MVP). This study reports 86 patients, average age 60 years, who presented with cardiac symptoms, precordial systolic murmur, severe MR and a high incidence of MVP on echocardiography (57 of 75 [75%] ) and left ventriculography (61 of 84 [73%] ). Seventy-five surgically excised mitral valves appeared grossly enlarged and floppy. Histologic studies showed extensive myxomatous changes throughout the leaflets and chordae. Eighty patients had had precordial murmurs first described at average age 34 years, but the average age at which symptoms of cardiac dysfunction appeared was 59. However, once symptoms developed, mitral valve surgery was required within 1 year in 67 of 76 patients who had undergone surgery. Atrial fibrillation, present in 48 of 86 patients (56%), or ruptured chordae tendineae, present in 39 of 76 patients (51%), may have contributed to this rapid progression and deterioration. Additionally, 13 patients had a remote history of documented infective endocarditis. Twenty-eight patients had at least 1 type of serial clinical evaluation that indicated progressive MR in all 28 patients on the basis of changing auscultatory findings (24 of 26), progressive radiographic cardiomegaly (24 of 25), echocardiographic left atrial enlargement (4.3 to 5 cm in 11 patients) and angiographically worsening MR (14 of 15). Twenty-four of these patients had evidence of MVP on at least 1 of their initial studies. Thus, mild MR due to MVP and myxomatous mitral valves is a progressive disease in some patients with MVP.

Pedunculated left ventricular rhabdomyoma.

A patient with an unusual left ventricular outflow tract obstruction caused by a solitary pedunculated left ventricular rhabdomyoma is described. Diagnosis was based on two-dimensional echocardiographic findings alone. The obstructive portion of the tumor was successfully removed from the interventricular septum by an aortic root approach.

Open lung biopsy. Its effects on therapy in the pediatric patient.

The records of 35 pediatric patients who had open lung biopsies at Columbus Children's Hospital, Columbus, Ohio, were analyzed to determine the results and the effects on therapy. Twenty-two (63 percent) of these patients were immunocompromised, and they are compared to the non-compromised group. A diagnosis was obtained in all cases. An infectious agent was identified in 13 (37 percent) of the patients. Ten of these were immunocompromised. In 43 percent (15 patients) of the total group and 55 percent (12 patients) of the immunocompromised group, the results of the biopsy effected a change in therapy. Five patients died, all of whom were immunosuppressed. None died as a direct result of the open lung biopsy. The total morbidity rate was 23 percent (eight patients). We concluded that open lung biopsy can be accomplished safely in the pediatric patient and that the results affect the therapeutic decision-making process a significant portion of the time.

Tricuspid stenosis. Atrial systolic murmur, tricuspid opening snap, and right atrial pressure pulse.

Observations on the atrial systolic murmur, the tricuspid opening snap, and the right atrial pressure pulse of tricuspid stenosis are presented, based on catheter manometer intracardiac sound and pressure recordings in five patients with hemodynamically significant tricuspid stenosis. The manometer-recorded right atrial pressure pulse of tricuspid stenosis differed from the normal, with (1) elevation of right atrial pressure, (2) different morphologic features (tall, spiky A wave complete before C; small V wave with an interruption, the tricuspid opening snap notch at termination of the gradual Y descent; a diastolic plateau, the relatively flat diastolic segment of the right atrial pressure pulse following the tricuspid opening snap notch prior to the next A wave), and (3) the relative lack of right atrial pressure and right atrial pressure pulse response with normal respiration. The atrial systolic murmur, recorded in the right ventricular inflow tract, was complete by S1; the crescendo-decrescendo atrial systolic murmur configuration paralleled the right ventricular-right atrial diastolic pressure gradient at the time of the atrial A wave. The right atrial contraction-relaxation process, as reflected by the right atrial A wave ascent and descent, was complete at the onset of ventricular systole with P-R intervals of 170 to 200 msec. Thus, the timing and configuration of the atrial systolic murmur reflected the timing and completion of the right atrial contraction-relaxation process prior to the onset of right ventricular systole and the configuration of the tricuspid diastolic pressure gradient. The tricuspid opening snap was recorded in the right ventricular inflow tract and occurred at the time of a notch at the termination of the Y descent of the right atrial pressure pulse V wave, while right atrial pressure exceeded right ventricular pressure. The sound-pressure events were consistent with angiographic and echocardiographic studies, which showed doming or ballooning of the mobile, fused, stenotic tricuspid valve into the right ventricle during the Y descent of the right atrial pressure pulse. The tricuspid opening snap occurred at the time of the termination of the diastolic movement of the fused tricuspid unit into the right ventricle. These observations are presented within the framework of previous studies in order to trace the development of medical ideas about the pathophysiologic basis for the sound and pressure events of tricuspid stenosis.

Cardiovascular abnormalities associated with adult polycystic kidney disease.

In a combined retrospective and prospective study, 11 patients with adult polycystic kidney disease were found to have one or more cardiac or aortic lesions. Seven patients had primary dilatation of the aortic root and annulus with aortic regurgitation. The severity of the aortic regurgitation necessitated aortic valve replacement in 2. Mitral regurgitation was present in 3 patients, of whom 2 had documented redundant mitral leaflets and ruptured chordae tendinae, and the third had mitral valve prolapse. Histologic analysis of available aortic and mitral valve tissue from these acquired lesions showed myxomatous degeneration with loss and disruption of collagen. Four patients had congenital bicuspid aortic valves with aortic regurgitation; 1 of these patients also had mild valvular stenosis, and 1 had coarctation of the aorta.

The effect of left atrial histology and dimension on P wave morphology.

This study correlates left atrial appendage cell size, atrial fibrosis and echocardiographic (echo) measurement of left atrial size with P wave morphology. Twelve patients with known mitral valve disease had echo measurements of left atrial size with P wave morphology. Twelve patients with known mitral valve disease had echo measurements of left atrial size prior to mitral valve surgery; patients had varying degrees of left atrial enlargement. The left atrial appendage, removed at the time of surgery, was stereologically assessed for percent fibrosis and the diameters of 50 cells were measured and averaged. These factors were correlated with P wave amplitude and duration in lead II, greatest length in any led, PR segment (end of P wave to onset of QRS), P to PR segment ratio (in lead II) and the PR interval. There was a good correlation of left atrial cell diameter with P wave amplitude (r = .69, p = 0.01). There was a good inverse correlation of percent fibrosis with the PR segment (r = -.72, p = 0.01) and a direct correlation of fibrosis with the ratio of P wave length to PR segment (r = .67 p = 0.01). There was a trend for percent fibrosis to correlate with PO wave duration but not height. No correlation was noted for any of the P wave characteristics and left atrial size. This study demonstrates that there is a correlation of P wave height with cell diameter and P wave length and PR segment with fibrosis. These data are helpful in understanding the electrocardiographic P wave.

Type IV total anomalous pulmonary venous connection. Unusual survival and review of the literature.

Total anomalous pulmonary venous connection (TAPVC) is a condition most frequently seen in the pediatric age group. Of those that survive uncorrected into adulthood, type I and type II constitute the great majority. It is most unusual to see a patient with a type IV lesion survive. We report a 34 year old female patient with TAPVC of the right upper lobe and left lung veins into the vertical vein and the right lower lobe vein into the coronary sinus. This patient has the second longest survival of those with type IV lesion of TAPVC, and the second oldest to have successful surgical correction. We attribute her long survival to the normal pulmonary artery pressure, a wide atrial septal defect and no other associated cardiac lesions. a review of the surgical survival in the English literature of patients with type IV TAPVC is presented.

Pharmacological blood pressure reduction as an adjunct in the operation for patent ductus arteriosus.

In some patients with patent ductus arteriosus, it is especially difficult to obtain an adequate length of the ductus for its safe division. In these patients, additional length can be obtained by pharmacological reduction of the blood pressure with sodium nitroprusside. The management of 2 such patients is reported.

Combined median sternotomy and posterior lateral thoracotomy: a method for proximal and distal thoracic aortic exposure.

A method for exposure of the heart, ascending aorta, aortic arch vessels, and descending thoracic aorta in a single surgical field is presented. Five illustrative cases are reviewed. Indications for use include trauma to the aorta and arch vessels, aneurysms or dissections, ductus aneurysms, or complex or secondary coarctations of the aorta.

Quantitative study of the rabbit aortic endothelium using vascular casts.

A quantitative study of the en face size and shape of rabbit endothelial cells from the ventral mid-thoracic and ventral infrarenal abdominal aorta has been carried out in 6 rabbits. Photomicrographs were taken from vascular casts of the rabbit aorta and the endothelial cell outlines were analyzed quantitatively using a digitizer and digital computer. The morphology of the endothelial cells was described using 8 calculated parameters (area, perimeter, length, width, angle of orientation, width:length ratio, axis intersection ratio and shape index). The endothelial cells in both locations had the same surface area (P greater than 0.30); however, the cells in the abdominal aorta were longer (P less than 0.01) and narrower (P less than 0.01) than those in the thoracic aorta. This fact is reflected by the smaller value for the shape index and width : length ratio in the abdominal aorta (P less than 0.01). Cells in both the thoracic and abdominal aorta were aligned with the flow direction.

Late failure of porcine valve heterografts in children.

Heterograft porcine valves have gained wide acceptance in replacement of diseased cardiac valves, and their clinical performance in adults has been very satisfactory over follow-up periods of up to 8 years. Valve replacement in children is relatively infrequent and experience with porcine xenografts is necessarily small. Our combined experience at three university hospitals has been with 25 children, 17 months to 16 years of age, who have been followed for 10 to 54 months (mean follow-up 33 months). Porcine valves were used to replace the aortic valve in nine, the mitral valve in seven, both valves in two, the tricuspid valve in two, and the pulmonary valve in five patients. Severe bioprosthetic valve dysfunction has occurred in five (20%) of these patients so far and necessitated replacement because of severe stenosis in mitral (two) or aortic (three) valve prostheses at 18 to 45 months after implantation; one postoperative death occurred among the five reoperations. Pathological examination showed extensive fragmentation of collagen with focal heavy calcification and degeneration. In addition we have encountered deterioration and calcification of two porcine valves in 23 valved conduits followed for 12 to 70 months (mean 43 months), requiring removal and replacement of the valves 65 and 67 months after implantation. This experience indicates a disquietingly high incidence of relatively early failure of porcine xenograft valves in children. This is significantly higher than the failure rate observed in adult patients. The failure rate is not consistently related to the small size of an implanted valve which becomes relatively narrow with the growth of the patient, leading to excessive turbulence and trauma to the prosthesis. Other factors, including increased turnover of calcium and accelerated rejection in growing children, may contribute to these failures and should be examined in order to improve long-term results. A satisfactory performance would make heterografts the ideal valvular prosthesis in children, since anticoagulation is avoided.

Alterations in gastrointestinal contents induced by elemental diets.

The effects of elemental diets on selected aspects of the rat colon were studied. Forty young male Sprague-Dawley rats were divided into 4 diet groups of 10 rats each: Purina Rat Chow (control); Flexical; Precision L-R; and Vivonex. All diets were fed ad lib to rats housed in pairs in wire-bottom cages. Two weeks after weight stabilization had been achieved all rats were killed and colon contents were collected for culture and short-chain fatty acid analysis on the Perkins-Elsoner 3920 gas chromatograph. Colon fecal butyric/acetic acid ratios of the rats in the 4 groups were: Rat Chow, 2.56; Flexical, 0.28; Precision L-R, 0.16; and Vivonex, 0.26. Bacterial cultures showed increased coliform and enterococcal species in the rats consuming elemental diets.