The late consequences of anthracycline treatment on left ventricular function after treatment for childhood cancer

The purpose of this study was to determine the incidence of changes in left ventricular function in patients in long-term remission after treatment with anthracyclines for a childhood malignancy. The authors examined 155 patients in disease remission who underwent treatment protocols utilising anthracyclines in childhood. The group comprised 90 males and 65 females aged 15±4.9 years (range 5–29 years, median 15 years). The age at the time of diagnosis and start of treatment was 8.6±4.9 years (range 1–18 years, median 8 years). The time of follow-up was 7.3±4 years (range 1–21 years, median 6.3 years). The patients were given a cumulative dose of doxorubicin or daunorubicin of 250±131 mg/m² (range 50–1200 mg/m², median 240 mg/m²). The values of ejection fraction below 55% and fractional shortening below 30% assessed by means of echocardiography were considered as pathological. The control group consisted of 41 volunteers. Pathological values of fractional shortening were found in 12 patients (8%). Only one patient (0.64%) showed the development of heart failure due to cardiomyopathy. The group of the patients after chemotherapy revealed significantly worse values of left ventricular endsystolic wall stress, mean velocity of circumferential fibre shortening, Tei index, and isovolumic relaxation period in comparison with the control group. We found a correlation between the given cumulative dose of anthracyclines and indicators of systolic function of the left ventricle, but not a relation to the time indicators (age at diagnosis, time of follow-up). Conclusion:in the mean period of 6 years after chemotherapy, subclinical cardiotoxicity was found in 11 patients (7%) and cardiomyopathy with heart failure in one patient. Further indicators of subclinical damage are elevation of afterload (end-systolic stress), impaired relaxation and increased value of the Doppler index of global left ventricular function. Further monitoring and evaluation of the relevant subclinical abnormalities over a longer period of time are needed.Abbreviations CD cumulative dose - DT deceleration time - E/A index of the diastolic filling of the left ventricle - EF ejection fraction - ESS end-systolic stress - FS fractional shortening - HR heart rate - IRT isovolumic relaxation time - LV left ventricle - LVPWDd end-diastolic diameter of the left ventricular posterior wall - LVPWex excursion of the left ventricular posterior wall - LVPWP percentage of the systolic thickening of the left ventricular posterior wall - MPI myocardial performance index - mVcf _c mean velocity of circumferential fibre shortening     

Left ventricular function and myocardial mass after aortic valvotomy in infancy

Summary Eighteen of 25 survivors of aortic valvotomy in infancy were reinvestigated by cross-sectional echocardiography a mean of 7.5 (2.3–13.4) years after surgery. They had been operated at a median age of 38 (5–330) days. At the follow-up examination the gradient across the aortic valve was 41±19 (15–85) mmHg and the ejection fraction was 0.73±0.10 (0.48–0.84). Left ventricular (LV) end-diastolic volume was 66±17 (33–191) ml/m². LV mass was 96±36 (44–204) g/m² and the LV mass volume index (LVMVI) (mass divided by end-diastolic volume) was 1.43±0.4 (0.9–2.28). Eleven of 18 patients had an abnormally high mass volume index compared with 95 age-matched controls with structurally normal hearts. The correlation between the residual pressure gradient across the aortic valve and mass volume index yielded anr value of 0.75 (p<0.0004). One patient had been reoperated and underwent resection of a subaortic stenosis 4 years after the initial operation. Four patients with a resting gradient of more than 50 mmHg and one with grade 4 aortic regurgitation are scheduled for further surgical treatment.We conclude that, although LV function was normal in most patients who underwent aortic valvotomy in infancy, LV mass remains elevated in a significant number of patients, who may remain at risk of developing subendocardial ischemia.     

Severity of Mitral Regurgitation Predicts Risk of Death or Cardiac Transplantation in Children With Idiopathic Dilated Cardiomyopathy

Clinical outcomes among children with idiopathic dilated cardiomyopathy (IDC) are diverse, which makes the decision as to when a patient should be listed for a cardiac transplantation challenging. This study aimed to determine echocardiographic and clinical variables that can help clinicians identify those at highest risk for death or cardiac transplantation. The study was a single-center, retrospective chart review of children with IDC. Patients younger than 18 years with a diagnosis of IDC, as defined by a left ventricular end-diastolic dimension (LVEDD) z-score higher than 2, and fractional shortening of less than 28 % on the initial echocardiogram, were included in the study. Echocardiographic parameters including mitral regurgitation (MR) grade and certain clinical parameters at the time of presentation were assessed. A follow-up echocardiogram was similarly studied. The study included 49 children with IDC. Those who died or underwent cardiac transplantation were grouped as “nonsurvivors” (n = 26). The remaining children who either completely recovered or experienced chronic dilated cardiomyopathy were grouped as “survivors” (n = 23). The median age overall was 1.25 years (range 0.1–17 years). The follow-up echocardiograms of the survivors showed significant improvement in left ventricle size, systolic function, left atrial volume, and MR grade, whereas these parameters did not change in the nonsurvivor group. The use of inotropic medications at initial presentation was an independent predictor of death or cardiac transplantation (p < 0.05). The presence of moderate to severe MR at diagnosis also was predictive of a worse outcome.     

Left ventricular myocardial mass determined by cross-sectional echocardiography in normal newborns,infants, and children

Summary Changes in left ventricular muscle mass may be an important diagnostic or prognostic finding in children with congenital heart defects, but there are no data on normal mass as determined by cross-sectional echocardiography (CSE) in children. Fourteen newborns, 12 infants, and 69 children (1.5–17 years old) with a structurally normal heart were studied. Enddiastolic and end-systolic volume and mass were calculated from biplane-paired echocardiographic imaging planes—apical two-chamber and apical four-chamber views—using both an area/length and a Simpson's rule geometric method. Data were compared with M-mode measurements. There was a good correlation between area/length and Simpson's rule method [r=0.94, standard error (SE) 4 g/m²].To validate the measurements, interobserver data were gathered and end-diastolic and endsystolic mass measurements were compared. Interobserver variability for the measurements on the echocardiographic recordings was low at 4.8%; for end-diastolic mass the correlation between two observers wasr=0.99 (SE 3.3 g/m²) and for end-systolic massr=0.97 (SE 7.6 g/m²). Correlation between end-systolic and end-diastolic mass was acceptable (r=0.88, SE 5.9 g/m²) for the CSE mass determination, but poor for the M-mode measurements (r=0.51, SE 20.2 g/m²). Similarly, correlation between M-mode mass and mass estimated by CSE was poor, atr=0.58 for end-diastolic andr=0.094 for end-systolic mass. In newborns and infants the ratio of end-diastolic mass to end-diastolic volume was higher than in the older children, mainly because of a smaller ventricular volume in relation to body surface area in this age group.In the 26 newborns and infants, left ventricular mass was 48.7±10 g/m² and volume was 34.6±7 ml/m², yielding a mas to volume ratio of 1.41±0.03. For the 69 children (mean age 7.4±3.8 years), left ventricular mass was 63±10 g/m² and volume 59±10 ml/m² with a mass to volume ratio of 1.07±0.2. Left ventricular end-diastolic mass and volume strongly correlated with age (r=0.9) and body surface area (r=0.98 and 0.97, respectively). As CSE is easy to perform and repeatable, these normal values should provide a valuable database for further longitudinal studies of the development of left ventricular mass in patients with various cardiac abnormalities.     

Doppler echocardiographic evaluation of left ventricular diastolic function after surgical correction of atrial septal defect during childhood

Summary Transmitral flow was studied using Doppler echocardiography with the A/E ratio as a parameter of left ventricular diastolic function in 21 patients (ages 2.5–30.0 years) who had undergone early surgical correction of an isolated secundum type atrial septal defect (ASD) compared to a healthy cohort of 21 subjects. Pre- and postoperative M-mode recordings were compared in 12 of the 21 patients to evaluate the effect of operation on interventricular septal motion (IVS) and left ventricular (LV) and right ventricular (RV) end-diastolic diameter ratio (LVDD/RVDD) as parameters of right ventricular volume overload. No significant difference in A/E ratio was found between the patient and control groups. IVS was shown to normalize in 11 of 12 patients postoperatively and to improve from paradox to flattened in 1 of 12. LVDD/RVDD increased from 1.26±0.31 to 2.10±0.51 (p=0.0008), with no significant difference remaining between the control and patient groups postoperatively. These findings support the conclusion that an intrinsic abnormality of the left ventricle is not responsible for its diastolic dysfunction in patients with ASD who develop left ventricular failure, thereby implicating an acquired abnormality. Mechanical sequelae of right ventricular volume overload were shown to normalize in all patients subsequent to operation in the present study, and therefore cannot be excluded as a cause of left ventricular failure in ASD.     

The effect of treatment with angiotensin-converting enzyme inhibitors on survival of pediatric patients with dilated cardiomyopathy

Summary Outcome in 81 pediatric patients with dilated cardiomyopathy was reviewed to assess whether treatment with angiotensin-converting enzyme (ACE) inhibitors affected survival. Age at onset was 3.6±0.6 years. Twenty-seven children (group 1) were treated with ACE inhibitors. Conventional therapy was used in the remaining 54 patients (group 2). There were no significant differences between the two groups in age at onset, left ventricular shortening fraction, left ventricular end-diastolic pressure, or mean pulmonary artery pressure. Patients treated with ACE inhibitors had a significantly better survival during the first year (p<0.05) with continuation of this trend throughout the second year (p=0.06). Beyond 2 years there was a tendency toward better survival in ACE inhibitor-treated patients, but the differences were no longer significant (p=0.14). These data, along with observations in adult patients with chronic cardiac failure, indicate that converting enzyme inhibitors have a beneficial effect on prolonging survival of infants and children with severe left ventricular dysfunction from dilated cardiomyopathy.     

Prognostic implications of left ventricular function in endomyocardial disease in infants and children.

Hemodynamic factors measured at cardiac catheterization in 40 infants and children with chronic endomyocardial disease were analyzed in regard to subsequent clinical condition. The patients were followed for periods ranging from 2 months to 11 years (average 4.3 years) after initial cardiac catheterization. There were no statistically significant differences in left ventricular end-diastolic volume among survivors with no symptoms, survivors with persistent congestive heart failure, and nonsurvivors. Ejection fractions were depressed in about four fifths of patients with chronic endomyocardial disease and were significantly lower in the group of patients who died subsequently. LVEDP in patients who did not survive was significantly higher than in asymptomatic survivors, but there was too much overlapping of individual values to be of prognostic value. Left ventricular pressure-volume loops appeared to offer an improved, although more tedious, method of assessing LV function. In addition to offering information on LVEDV, LVEDP, and EjF, LV stroke work may easily be estimated from pressure-volume loops. There was generally good correlation between hemodynamic status assessed from pressure-volume loops and subsequent clinical outcome.     

Right and left ventricular pump function in infants and children with primary myocardial disease presenting with heart failure

Summary Right and left ventricular (RV, LV) function were evaluated by quantitative bi-plane cineangiocardiography in 20 patients, aged 1 day to 6 years, who had primary myocardial disease presenting with heart failure. RV end-diastolic volume (RVEDV) was 157%±63% ( ±SD) of normal (P<.01), and RV ejection fraction (EF) was 0.39±0.16 (normal, 0.65±0.08) (P<.01). Left Ventricular end-diastolic volume (LVEDV) was 331%±172% of normal and LVEF 0.26±0.12 (normal, 0.68±0.05); both values were different from normal (P<.01) and also different from corresponding RV values (P<.01). RVEDV was larger than LVEDV in only four patients, these four patients being the youngest patients in the entire group, all 10 days of age or younger. A subgroup of 14 patients with subnormal RVEF (RVEF> –2 SDs of normal) were compared with six patients with normal RVEF. Patients with subnormal RVEF had larger left ventricles, lower LVEFs, and higher RV peak systolic pressure than those with normal RVEF (P<.05 for all three comparisons). A separate subgroup of ten patients who died was compared with a subgroup of eight surviving patients followed up for one to four years after diagnosis. Patients who died had lower values for LVEF and LV systolic output and higher values for LV end-diastolic pressure than did survivors. There were no significant differences between patients who died and survivors in any of the RV variables measured. RV functional abnormalities were generally present in both infants and children who had myocardial disease presenting with heart failure and may especially contribute to the symptoms in infants.Supported in part by grant HL 21985-01 from the National Heart, Lung, and Blood Institute     

Effect of increase in heart rate on interatrial shunt in atrial septal defect

Summary The effect of increases in heart rate by atrial pacing was investigated in 20 children [mean 9±4 (SD) years] with atrial septal defect. Systemic blood flow increased by 13±10 and 27±22% with a 25 and 50% increase in heart rate, respectively. Pulmonary blood flow, however, remained unaltered. Thus, rapid pacing decreased the pulmonary to systemic blood flow ratio significantly (–15±10 and –22±13%, respectively). This hemodynamic alteration was attributed to the difference in diastolic distensibility (compliance) between the left and right ventricles, and the ratio of right ventricular to left ventricular compliance (defined by dV/dP) near the end-diastolic pressure was estimated to be 6.5±4.2. It is suspected that the increase in heart rate may contribute to the lowering of pulmonary to systemic flow ratio during exercise in children with atrial septal defect.     

Favorable effects of immunosuppressive therapy in children with dilated cardiomyopathy and active myocarditis

Among 68 children with severe dilated cardiomyopathy, 43 (aged 10 months to 15 years) presented with active myocarditis, diagnosed by endomyocardial biopsy. They were divided into four treatment groups: I, controls: 9 patients submitted to conventional treatment (digitalis, diuretics, and vasodilators) for 8.1±0.7 (SD) months; II, prednisone: 12 patients received conventional therapy plus prednisone; III, azathioprine: 16 patients submitted to conventional therapy plus prednisone and azathioprine; IV, cyclosporine: 13 patients treated with conventional therapy plus prednisone and cyclosporine. Immunosuppressive therapy was maintained for a mean of 8.4±1.2 months. They were submitted to noninvasive (electrocardiogram, chest radiograph, Doppler echocardiogram, and radioisotopic scintigraphy) and invasive (hemodynamic) studies. In the control group only 2 of 9 patients showed clinical and hemodynamic improvement and 1 of 4, histologic regression of the myocarditis. Among patients submitted to conventional therapy plus prednisone, 3 of 12 presented clinical and hemodynamic improvement; 2 of 5 also showed histologic regression of inflammatory process. By contrast, patients treated with azathioprine or cyclosporine associated with prednisone had significantly better results: 13 of 16 and 10 of 13 patients, respectively, had clinical and hemodynamic improvement; all 6 patients in the azathioprine group and all 4 patients in the cyclosporine group had histologic regression of the myocarditis. Two patients in the prednisone group, one in the azathioprine group, and one in the cyclosporine group died during treatment, in cardiogenic shock. In our experience immunosuppressive therapy with azathioprine or cyclosporine associated with prednisone improves the prognosis of children with active myocarditis and severe ventricular dysfunction.     

Medical Therapy Leads to Favorable Remodeling in Left Ventricular Non-compaction Cardiomyopathy: Dilated Phenotype

Left ventricular non-compaction cardiomyopathy (LVNC) is a distinct and heterogeneous entity that can lead to progressive cardiac dysfunction and heart failure. LVNC with dilation and/or dysfunction is associated with a greater mortality risk. We hypothesized that initiation of heart failure medications in patients with LVNC and ventricular dysfunction or dilation would improve systolic function and result in favorable left ventricular remodeling. The study was a retrospective chart review. Inclusion criteria included: presence of LVNC, reduced systolic function or ventricular dilation, therapy with at least one medication (beta blocker, angiotensin-converting-enzyme inhibitor, angiotensin II receptor blocker), imaging pre- and post-initiation of therapy. Fifty-one patients met inclusion criteria. Mean age at initiation of medication was 11.5 ± 11.8 years. Follow-up was 2.4 ± 2.3 years. Three patients (6 %) were solely on a beta blocker, 15 (29 %) on ACE/ARB monotherapy, and 33 (65 %) on dual therapy. At follow-up 45/51 patients (88 %) had improvement in ejection fraction/shortening and 6/51 (12 %) had no change. Ejection fraction, shortening fraction, and left ventricular end-diastolic dimension in the cohort before and after therapeutic intervention demonstrated a 16 ± 12 % improvement in ejection fraction (p < 0.0001), an 8 ± 9 % improvement in shortening fraction (p < 0.0001), and a 0.83 ± 1.93 (p < 0.05) decrease in left ventricular end-diastolic z-score. Early diagnosis and medical treatment of LVNC with reduced systolic function and/or dilation leads to favorable remodeling evident by an improvement in ventricular systolic function and reduction of ventricular end-diastolic dimensions.     

Brock transventricular pulmonary valvotomy in patients with pulmonary stenosis: Long-term results

Summary As no long-term results of a blind opening up of the pulmonary valve either by balloon valvoplasty or closed Brock valvotomy have been published, we examined the outcome of 12 patients with valvar pulmonary stenosis 17±5 (11–22) years after surgery. The Brock valvotomy had been carried out at a mean age of 3±2.8 (0.2–8.5) years. The mean pressure gradient across the right ventricular outflow tract had been 116±45 (75–97) mmHg at the catheter study or 106±43 (40–160) mmHg as measured intraoperatively. The right ventricular pressure after the Brock procedure was measured in the operating room in five patients as 46±15 (30–60) mmHg. Seven patients had been recatheterized at a mean age of 9.5±2 (7–12.7) years; at that time the gradient across the pulmonary valve had been 20±14 (10–37) mmHg. At a mean age of 21.7±3 (15–26) years these and five further patients were reexamined by echo Doppler. This time the pressure gradient across the pulmonary valve was 13±6 (7–20) mmHg. Moderate pulmonary incompetence was present in four and mild incompetence in eight patients; two had mild tricuspid insufficiency. All except one patient, who had suffered a cerebrovascular accident before surgery, were in NYHA functional class 1 and pursuing a profession. From these data we conclude that the blind opening-up of the pulmonary valve achieves excellent long-term palliation.     

Myocardial oxygen consumption,cardiac work,and myocardial efficiency in children

Few reports on human cardiac functional development exist, although this information is important for managing paediatric heart disease. The work and the energy usage of the heart was measured in children. A total of 58 patients (aged 1–19 years) with a history of Kawasaki disease without coronary sequelae underwent cardiac catheterization to obtain haemodynamic data and to measure myocardial oxygen consumption. Myocardial oxygen consumption (ml/min) (y=0.63 x+3.6,r=0.86,P<0.0001,x=age) and left ventricular minute work (kg m/min) (y=0.46 x+2.4,r=0.84,P<0.0001, x=age) correlated positively with age. However, left ventricular minute work per body surface area (age: 2–5 years, 5.8±0.34 kg m/min/m²; age: 6–10 years, 6.9±0.59 kg m/min/m²; age: 11–15 years, 5.9±0.51 kg m/min/m²; age: 16–19 years, 6.5±0,29 kg m/min/m²; and myocardial efficiency (age: 2–5 years, 40.1±4.4%; age: 6–10 years, 42.4±3.9%; age: 11–15 years, 45.9±4.1%; age: 15–19 years, 42.3±6.6%) remained constant throughout childhood.Conclusion In spite of the structural immaturity of the developing heart, the myocardial oxygen consumption per body surface area and myocardial efficiency led by the cardiac work are the same in adults and in children older than 1 year of age.     

Left ventricular contractile state after surgical correction of tetralogy of Fallot: Risk factors for late left ventricular dysfunction

Summary The purpose of this study was to analyze potential risk-factors for late left ventricular dysfunction after surgical correction of Fallot's tetralogy (FT). As the ejection-phase indices cannot distinguish abnormalities of contractility from altered loading conditions, the slope values of the end-systolic pressure-length and stress-shortening relationships were analyzed by increasing afterload. Thirty-two patients were studied after surgical correction of FT in infancy. The age at investigation was 19.2±5.6 years, total correction had been performed at the age of 7.7±3.3 years. In 20 patients a one-stage operation was performed, and in 12 patients a two-stage correction. The control group consisted of 30 healthy volunteers, aged 18–30 years. The following potential risk factors for left ventricular dysfunction were evaluated: one-stage vs. two-stage correction, age at total correction, preoperative systemic oxygen saturation, preoperative hematocrit, occurrence of hypoxic spells, preoperative ratio of left-to-right ventricular peak systolic pressure, and preoperative ratio of left-to-right ventricular end-diastolic volume. In most patients the baseline data for end-systolic wall stress lay outside the normal range, indicating abnormal loading conditions. Thus, analysis of load-independent indices of the contractile state seems to be mandatory in these patients. Our data show that the severity of preoperative hypoxemia is an important risk factor for late dysfunction of the left ventricle (p<0.01). Additionally, the relation of left and right ventricular peak systolic pressures and enddiastolic volumes were related to the contractile state (p<0.01). No influence of preoperative hypoxic spells, the need for a palliative aortopulmonary shunt, or the age at surgical correction on the postoperative contractile state was demonstrated. The latter may have been due to the fact that none of the patients were operated on within the first 2 years of life.     

Noncompaction Cardiomyopathy in Children With Congenital Heart Disease: Evaluation Using Cardiovascular Magnetic Resonance Imaging

Noncompaction of the left ventricle, a genetic cardiomyopathy with a reported incidence of 0.05% to 0.24%, can lead to sudden cardiac death, particularly among children, if left undetected. Because the diagnosis of isolated noncompaction cardiomyopathy (NCM) can be overlooked, its association with other congenital heart diseases (CHDs) makes the diagnosis of NCM even more difficult. This study aimed to assess the impact of NCM on the cardiovascular physiology of children with coexisting CHDs evaluated by cardiovascular magnetic resonance imaging. A case-control study was performed with 12 children (6 patients with combined NCM and CHD and 6 control subjects with isolated CHD). The mean left ventricular end-diastolic and end-systolic volume indices were significantly higher in the CHD patients presenting with NCM than in the CHD patients with no NCM (P = 0.028). However, no differences were observed for right ventricular end-diastolic and end-systolic volume indices, biventricular ejection fractions, stroke volumes and indices, left ventricular wall thickness, left ventricular fractional shortening, cardiac output, or cardiac index. This study suggests that NCM in children with CHDs increases left ventricular volumes, and larger studies are required to demonstrate other changes (e.g., ejection fraction, stroke volume) that were close to being significant.     

Severe Pulmonary Regurgitation Late After Total Repair of Tetralogy of Fallot: Surgical Considerations

Background After total repair of tetralogy of Fallot (TOF-R) with transannular patching (TAP), severe pulmonary regurgitation (PR) is reported to develop in up to 30% of patients at a follow-up of 20 years, and 10–15% or more need pulmonary valve replacement (PVR). In this study, time-related progression of PR and right ventricular (RV) dilatation, and functional recovery of the RV after PVR are analyzed, and the possible causes of PR and timing of PVR are discussed.Methods Eighteen patients, who late after TOF-R with TAP underwent PVR for severe PR, were chosen for the study. NYHA class, QRS duration, RV dilatation index (RVDI = RVEDD/LVEDD), and RV–distal pulmonary artery (PA) peak systolic gradient were reviewed and retrospectively analyzed.Results TOF-R was performed at a mean age of 5.1 ± 3.9 years (range: 0.6–12.8 years); the mean time interval from TOF-R to PR grade 3 onset was 11.8 ± 7.0 years (range: 3.3–27.4 years), and from TOF-R to PVR was 18.5 ± 7.8 years (range: 8.7–37.1 years).At PVR, 11 patients were in NYHA class II–III, all patients had severe PR (grade 3/3) and severe RV enlargement, 4 patients had ventricular arrhythmias, 7 patients significant distal pulmonary artery stenosis, and 2 patients small nonrelevant residual VSD. The mean preoperative RVDI (normal: 0.5) was 0.99 ± 0.14 (range: 0.75–1.3), the mean QRS duration 170 ± 24 ms (140–220 ms), and the mean RV–distal PA peak systolic pressure gradient 33.3 ± 19.0 mmHg (range: 10–60 mmHg). Patients aged at TOF-R> 5 years had considerably longer redo-free intervals than their younger counterparts: mean 23.1 years (range 8.7–37.1 years) vs 14.8 years (range: 9.3–21.2 years), respectively. The redo-free intervals and the duration of severe PR correlated inversely with the RV-PA gradient.At a mean follow-up of 1.3 years (2 weeks–5 years), the mean RVDI decreased from 0.99 ± 0.14 to 0.69 ± 0.15, the mean validity class improved from 2.5 to 1.1. One patient died.Conclusions After TOF-R with TAP, the progression of PR has very individual dynamics, resulting in extremely varying redo-free intervals. Concomitant pulmonary stenosis seems to exaggerate progression of PR. PVR results in effective reduction of diastolic dimensions of severely dilated RV and in improvement of validity class. Referred PVR in no-risk cases seems to be justified.Presented at the 32nd Annual Meeting of the GSTCS, Leipzig, Germany, 24 February 2003.     

M-mode echocardiographic findings in children with idiopathic restrictive cardiomyopathy

Summary The M-mode echocardiographic findings in five pediatric patients, ages 4–15 years, with primary idiopathic restrictive cardiomyopathy, diagnosed by cardiac catheterization, and of 12 normal children (control group) are presented. The M-mode echocardiographic findings in patients with restrictive cardiomyopathy were (1) normal left and right ventricular end-diastolic dimension, (2) normal left ventricular posterior wall and interventricular septal thickness (three patients) or mild concentric hypertrophy (two patients), (3) normal opening and closing velocity of the mitral valve, (4) consistently enlarged left atrium (more than 40 mm) in all, and (5) right ventricular systolic time intervals compatible with pulmonary artery hypertension. The left ventricular ejection phase parameters (systolic time intervals, shortening fraction, and mean velocity of circumferential fiber shortening) were normal. Left ventricular relaxation phase parameters (diastolic function) were abnormal. The isovolumic relaxation time index was prolonged, 68±40 ms (±SD), in the study group as compared with 11±6 ms (±SD) in the control group (P<0.001). Percent relaxation of left ventricular posterior wall endocardium at 50% of diastole was decreased, 58±4% (±SD), in the study group as compared with 85±6% (±SD) in the control group (P<0.005). We conclude that M-mode echocardiography provides arelatively useful and specific noninvasive method for the diagnosis of primary restrictive cardiomyopathy in pediatric patients. This work was supported in part by NHLBI grant HL07436.     

Cardiopulmonary abnormalities in severe acute respiratory failure

Serial cardiopulmonary variables were recorded over 4 days in 23 children with severe acute respiratory failure. In all patients, pulmonary artery catheters were inserted within 24 hours of the diagnosis of respiratory failure, and all required greater than 10 cm H2O positive end-expiratory pressure to achieve adequate oxygenation. Eight patients died (35% mortality). Evaluation of systemic hemodynamic variables indicated that survivors had higher blood pressures than nonsurvivors, although neither group was in the hypotensive range. Systemic vascular resistance was lower in the nonsurvivors. Cardiac function as evaluated by cardiac index, right ventricular stroke work index, and left ventricular stroke work index was similar in both groups. Survivors demonstrated elevations in mean pulmonary artery pressure and pulmonary vascular resistance during the first 36 hours, with gradual improvement thereafter. In contrast, pulmonary artery pressure and resistance increased progressively in patients who died. Intrapulmonary shunt fractions remained high in the nonsurvivors despite the use of up to 25 cm H2O PEEP. Cardiac function and oxygen delivery were well maintained in both groups despite the high levels of PEEP.     

Left ventricular thrombi in three children with dilated cardiomyopathy: Diagnostic procedure and clinical course

Summary In three of nine children with dilated cardiomyopathy (aged 1–9 years), left ventricular thrombi were diagnosed and followed by echocardiography. Thrombi recurred in two patients, in one of them, embolized to the cerebral arteries. Resolution of the thrombi was observed under therapy directed against platelet aggregation. However, this did not prevent thrombus formation.     

Acute renal failure complicating pediatric cardiac surgery: A comparison of survivors and nonsurvivors following acute peritoneal dialysis

Summary The outlook for patients with cardiac surgery complicated by acute renal failure (ARF) is poor, with a reported mortality of 50–67%. In addition to assessing the impact of recent advances in pediatric cardiac surgery on the mortality rate and renal outcome of surgery complicated by ARF requiring peritoneal dialysis (PD), this study compares preoperative, operative, and postoperative variables in patients who survived surgery and those who did not survive. From 1982 through 1988, 44 postoperative cardiac patients developed ARF, and 40 (age: 2 days to 15 years) required PD. Seventeen of 40 patients survived (mortality 57.5%) and 16 of these patients recovered normal renal function. Preoperative variables, including operative age and weight, did not appear to directly influence survival. Operative profiles, including length of cardiopulmonary bypass, aortic cross-clamp time, and hypotension immediately off bypass, did not distinguish surviving patients from those that did not survive. Postoperative variables, such as postoperative hypotension treatment, arrhythmias, hematologic status, cardiac arrest with resuscitation, did not differentiate survivors from nonsurvivors. The mean duration of PD was less than 2 weeks, and compications were infrequent. Renal status following PD in survivors was usually normal.We conclude that recent advances in pediatric cardiac surgery have not further increased the high mortality of surgery complicated by ARF. Survival is associated with renal recovery and thus aggressive treatment using PD is warranted.