Ian C. Balfour

Clinical profile of conjestive cardiomyopathy in children

Abstract The clinical profile of 23 children with congestive cardiomyopathy was reviewed to detect any factors that might be predictive for their survival. Factors examined include age at onset ( 2 years), geader, severity of the clinical picture including data from the chest radiograph electrocardiogram (ECG), echocardiogram, hemedynamic study and endomyocardial biopsy. Follow-up study ranged from 1 month to 14 years (mean 43 months). There were 12 survivors and 11 nonsurvivors; the 1 year mortality rate was 30% (7 of 23), and the 5 year mortality rate was 44% (10 of 23). Age at onset, gender, cardiothoracic ratio on chest radiograph, pattern of infarction, ST-T changes or arrhythmia on ECG and left ventricular enddiastolic pressure were nonpredictive of outcome. However, low shortening fraction (mean 11.5% in nonsurvivors versus 20.9% in survivors, p

Clinical spectrum of restrictive cardiomyopathy in children

We reviewed the clinical spectrum and possible prognostic factors in 14 children with restrictive cardiomyopathy. The patients were not homogeneous in clinical presentation or morphology. The mortality rate was high: 21.4% at 1 year and 50% at 2 years after presentation. Younger patients with respiratory symptoms, thromboembolism, increased cardiothoracic ratio on chest radiogram or patients with endocardial fibroelastosis appear to have a worse prognosis and orthotopic cardiac transplantation may be indicated.

Left ventricular filling in sickle cell anemia

M-mode echocardiography was performed on 11 normal black subjects and 38 patients with sickle cell anemia while they were at rest to evaluate their left ventricular (LV) systolic and diastolic function. The patients with sickle cell anemia were also evaluated by radionuclide exercise tests and, based on their ejection fraction (EF) response, were separated into 2 groups: a group with a normal EF response to exercise (73 +/- 9%, mean +/- standard deviation) and a group with an abnormal EF response to exercise (53 +/- 9%). Computer-assisted analysis of the M-mode echocardiograms identified abnormalities of diastolic function (impaired left ventricular filling) in patients with sickle cell anemia compared with the normal subjects. The abnormal EF response group had significantly more impaired diastolic function and did less exercise than the normal EF response group. Both groups of patients had a decrease in left ventricular end-diastolic volume during exercise. The patients with sickle cell anemia had abnormalities of systolic and diastolic function on echocardiographic and radionuclide testing. The abnormalities in diastolic and systolic function assumed greater significance at the increased heart rates associated with exercise, accounting for the decrease in left ventricular end-diastolic volume and the abnormal EF response, and contributed to exercise intolerance in patients with sickle cell anemia.

Familial syndrome of progressive arterial occlusive disease consistent with fibromuscular dysplasia, hypertension, congenital cardiac defects, bone fragility, brachysyndactyly, and learning disabilities

We report on 4 of 9 sibs with a syndrome of stenosis of the renal arteries and chronic hypertension, variable stenosis or occlusion of cerebral, abdominal and probably coronary arteries due to suspected fibromuscular dysplasia, congenital cardiac abnormalities, brachydactyly and syndactyly of the hands and feet, and increased bone fragility consistent with a mild form of osteogenesis imperfecta. Three affected individuals have had mild to moderate learning disabilities. The parents and the remaining 5 sibs have normal hands and feet and no history of excessive fractures. Individual components of this syndrome may appear as isolated conditions, including fibromuscular dysplasia, brachydactyly, syndactyly, and osteogenesis imperfecta, and are autosomal dominant traits in many cases. Explanations for this familial occurrence include autosomal recessive inheritance, autosomal dominant inheritance with decreased penetrance, or parental gonadal mosaicism for a mutation involving a single gene or several contiguous genes.

Transthoracic Doppler Echocardiography of Normally Originating Coronary Arteries in Children

Transthoracic Doppler color flow and spectral velocity patterns of normal coronary arteries in children have not been well studied. We designed this study to evaluate coronary artery flow velocity characteristics in normal and hypertrophied hearts. Sixty-eight children with optimal two-dimensional echocardiographic images of the left coronary artery (LCA) and right coronary artery (RCA) were prospectively studied. The heart was normal in 45 children, and 23 had left and/or right ventricular hypertrophy assessed by echocardiography (mean age 5.8 versus 5.2 years, p = NS). Color flow signals were detected in the LCA in 63(92%) of the 68 children studied, and pulsed Doppler spectral waveforms were recorded in 47 (69%). The latter were recorded in 26 (58%) of 45 normal children and in 21 (91%) of 23 children with left ventricular hypertrophy. Diastolic RCA flow signals were detected mostly in those with right ventricular hypertrophy (10 of 10). Higher levels of LCA maximum diastolic velocity (42 +/- 23 versus 24 +/- 6 cm/sec, p = 0.0004), increased diastolic flow (16 +/- 15 versus 6 +/- 4 ml/min, p = 0.01), and delayed time to peak diastolic velocity expressed as a percentage of diastolic spectral duration (38% +/- 14% versus 20% +/- 8%, p = 0.0001) were observed in children with left ventricular hypertrophy than in those in normal children. A strong correlation was present between Doppler-derived LCA flow and left ventricular mass/m2 (r = 0.7, p = 0.001). In normal hearts, LCA spectral velocity pattern did not change with increasing age, but the time velocity integral became progressively larger, resulting in a strong correlation with weight (p < 0.001, r = 0.78). This study demonstrates (1) LCA flow signals can be detected and quantitated in the majority of children with and those without left ventricular hypertrophy. (2) Left ventricular hypertrophy is associated with increased LCA flow, higher diastolic velocity, and delayed peak diastolic velocity. (3) RCA flow signals are mostly detected when there is right ventricular hypertrophy. Studies on larger groups of patients are needed to further confirm our observations and to enhance understanding of coronary artery flow reserve.

Miscellaneous TopicExercise-induced cardiac dysfunction in sickle cell anemia: A radionuclide study*

Cardiac performance was studied by radionuclide angiography at rest and during exercise in 22 adolescents with sickle cell (SC) anemia and the results were compared with those in 12 control subjects. At rest, cardiac contractility was normal; cardiac output and end-diastolic volume were increased. At maximal exercise, heart rate, cardiac output response, and work capacity were reduced; the reduction was related to the degree of anemia. Left ventricular end-diastolic volume decreased with exercise most markedly in patients with ischemic exercise electrocardiograms. An abnormal ejection fraction response to exercise occurred in 4 patients; electrocardiographic signs of ischemia developed in all 4, and wall motion abnormalities in 2. Those patients who had electrocardiographic signs of ischemia had a significantly lower heart rate, ejection fraction, and cardiac output response to exercise, and a lower hematocrit level than subjects with normal results on exercise electrocardiography. The increase in cardiac output was not sufficient to maintain a normal level of exercise. The decrease in end-diastolic volume suggests that diastolic function was abnormal during exercise. Cardiac dysfunction was manifested by an abnormal ejection fraction response, wall motion abnormalities, and incomplete left ventricular filling during exercise.

Effectiveness of five-loop coils to occlude patent ductus arteriosus

Coil occlusion of patent ductus arteriosus with 5-loop coils was undertaken in 10 patients without coil embolizations, and with 90% immediate occlusion and 100% occlusion at follow-up. We conclude that 5-loop coil occlusion of patent ductus arteriosus is safe and effective.

Transcatheter management of neonates with pulmonary atresia and intact ventricular septum.

This report describes a 1 day-old infant with valvar pulmonary atresia with intact ventricular septum in whom we were successful in performing transcatheter guidewire perforation and balloon pulmonary valvuloplasty to establish right ventricle-to-pulmonary artery continuity and flow. Also described is implantation of a 4 mm coronary stent into ductus arteriosus in lieu of surgical aortopulmonary shunt to treat pulmonary oligemia and systemic arterial hypoxemia. Details of transcatheter guidewire perforation are presented and it is suggested that this method be used as an alternative to Laser/radio frequency wires, especially in the absence of approval of the latter wires by the regulatory agencies. Stenting of the ductus may be considered an alternative to surgical aortopulmonary shunt. Role of transcatheter technology in the management of selected patients with pulmonary atresia and intact ventricular septum is discussed.

Aberrant Coronary Arteries: A Reliable Echocardiographic Screening Method

BACKGROUND Aberrant origin (ABO) of a coronary artery (CA) from the contralateral aortic sinus with a subsequent interarterial course is a life-threatening condition. It carries a 28% to 55% risk for a sudden coronary event or death, but there are no reliable screening methods. OBJECTIVE We sought to determine whether imaging a cross section of a coronary segment in the anterior aortic wall on the long-axis view may be used as an echocardiographic screening sign for ABO CA. METHODS The echocardiograms of all patients with ABO CA were evaluated for the screening sign and compared with those of age-matched control patients. RESULTS Between January 1989 and October 2002, we identified 8 patients with ABO CA (median age: 15 years). Of these patients, 4 were symptomatic and 4 were discovered incidentally. The electrocardiogram produced normal findings in 5 of 8 patients, maximal stress test produced normal findings in 5 of 6 patients, and thallium perfusion test produced negative results in 2 of 3 patients. There were 4 patients with ABO in the main left CA, 3 with ABO in the right CA, and 1 with ABO in the circumflex CA branch. The screening sign was readily visible in 7 of the 8 patients (88%), and all 7 of these patients had ABO in a main CA. Only in the ABO in the circumflex CA branch was the screening sign not detected. The 1743 control patients (median age: 14 years) showed normal anterior aortic wall, which was void of any CA segment. In 5 control patients (0.3%, P <.001) the normal right CA was visible on the long-axis view, but was not confused for a false-positive screening sign. CONCLUSION We concluded that the proposed screening sign for ABO CA is reliable and easily recognizable, and should prompt a comprehensive assessment of the CA.

Five-loop coil occlusion of patent ductus arteriosus prevents recurrence of shunt at follow-up †

Recent reports suggest reopening of the patent ductus arteriosus (PDA) after complete occlusion with three‐loop Gianturco coils. We hypothesize that five‐loop coils may produce a larger thrombus than three‐loop coils, which will result in no or less probability of recanalization of PDA during follow‐up. This study is designed to test this hypothesis. Follow‐up echocardiographic and Doppler data of 30 patients who underwent five‐loop coil occlusion of small to medium‐sized PDA during a 33‐month period ending December 1998 were examined. Thirty patients had no residual shunt on echo Doppler study on the day following the procedure and were followed for 6 to 30 months (median, 12) after coil implantation. At the last follow‐up study, none of the patients had a residual shunt and left atrial size decreased. Careful pulsed, continuous wave, and color Doppler interrogation of left/main pulmonary artery junction and proximal descending aorta did not reveal any evidence for obstruction. The follow‐up data suggest that complete occlusion of small‐ to medium‐sized PDAs is feasible with five‐loop coils without evidence for recanalization at a mean follow‐up of 12 months. Much longer (2 to 5 years) follow‐up data may be necessary to confirm these observations. We speculate that a greater degree of thrombosis is produced within the ductus by the five‐loop coils, which in turn may be responsible for lack of shunt recurrence. We recommend use of five‐loop instead of three‐loop coils for transcatheter occlusion of small‐ to medium‐sized PDAs. Cathet. Cardiovasc. Intervent. 50:202–206, 2000.