Quadriceps or triceps surae proprioceptive neuromuscular facilitation stretching with post-stretching dynamic activities does not induce acute changes in running economy.

Previous studies reported that both a more compliant quadriceps tendon and a stiffer Achilles tendon are associated with better running economy. While tendon stiffness can be decreased by a single bout of proprioceptive neuromuscular facilitation (PNF), post-stretching dynamic activities (PSA) can counteract the potential stretch-induced force loss. Thus, the purpose of this study was to investigate if a single, moderate duration, (4 × 15 s), bout of PNF stretching of either the quadriceps or triceps surae muscles followed each by PSA, causes either an improvement or impairment in running economy. Eighteen trained male runners/triathletes visited the laboratory five times. The first two visits were to familiarize the participants and to test for maximal oxygen consumption (VO2max) respectively. The further three appointments were randomly assigned to either 1.) quadriceps PNF stretching + PSA or 2.) triceps surae PNF stretching + PSA or 3.) no stretching + PSA. Following the interventions, participants performed a 15-min run on the treadmill with a speed reflecting a velocity of 70% VO2max to assess oxygen consumption (i.e., running economy) and running biomechanics. Our results showed neither a difference in oxygen consumption (p = 0.15) nor a change in any variable of the running biomechanics (p > 0.33) during the steady-state (i.e., last 5 min) of the 15-min run. Athletes can perform moderate duration PNF stretching of the quadriceps or triceps surae + PSA prior to a running event, without affecting running economy. Future studies should emphasize long-term training effects on tendon stiffness adaptations and running economy.

Does postexercise modelled capillary blood flow accurately reflect cardiovascular effects by different exercise intensities?

Blood flow (BF) in exercising muscles is an important factor for exercise capacity. Recently, a non-invasive method to estimate capillary BF (Qcap ) was introduced. Using this method, the Fick principle is re-arranged by using relative differences in deoxygenated haemoglobin (ΔHHb) as a surrogate for arteriovenous O2 difference and pulmonary oxygen uptake (VO2 ) instead of muscular oxygen uptake. The aim of this study was to examine (I) the relationship between Qcap and exercise intensity during and following exercise, and (II) to critically reflect the Qcap approach. Seventeen male subjects completed six bouts of cycling exercise with different exercise intensities (40-90% peak oxygen uptake, VO2peak ) in randomized order. VO2 and ΔHHb were monitored continuously during the trail. Qcap was modelled bi-exponentially, and mean response time (MRT) was calculated during recovery as well as the dissociation of modelled VO2 and Qcap recovery kinetics (MRT/τVO2 ). End-exercise Qcap increased continuously with exercise intensity. This also applied to MRT. Postexercise MRT/τVO2 increased from 40 to 60% VO2peak but remained stable thereafter. The results show that Qcap response to exercise is linearly related to exercise intensity. This is presumably due to vasoactive factors like shear-stress or endothelial-mediated vasodilation. MRT/τVO2 shows that postexercise Qcap is elevated for a longer period than VO2 , which is representative for metabolic demand following exercise ≥70% VO2peak . This is a hint for prolonged local vasodilation. According to previous studies, Qcap could not be modelled properly in some cases, which is a limitation to the method and therefore has to be interpreted with caution.

Oxygen consumption of gastrocnemius medialis muscle during submaximal voluntary isometric contractions with and without preceding stretch.

After an active muscle stretch, maintaining a certain amount of force in the following isometric phase is accompanied by less muscle activation compared to an isometric contraction without preceding active stretch at the corresponding muscle length. This reduced muscle activation might be related to reduced metabolic costs, such as the oxidative metabolism. Hence, the aim of this study was to clarify if mechanisms associated with stretch-induced activation reduction (AR) also influence oxygen consumption of voluntary activated human muscles after active stretch. Plantarflexion torque of 20 subjects was measured during 1) purely isometric and 2) active stretch contractions (26°, 60°/s), at a submaximal torque level of 30% MVC. Oxygen consumption (m[Formula: see text]O2) of gastrocnemius medialis (GM) was estimated by near-infrared spectroscopy while applying arterial occlusion. Since the overall group did not show AR at GM after active stretch (p > 0.19), a subgroup was defined (n = 10) showing AR of 13.0 ± 10.3% (p = 0.00). However, for both purely isometric and active contractions m[Formula: see text]O2 was the same (p = 0.32). Therefore, AR triggered by active stretch did not affect m[Formula: see text]O2 of active human muscle.

End-exercise ΔHHb/ΔVO2 and post-exercise local oxygen availability in relation to exercise intensity.

Increased local blood supply is thought to be one of the mechanisms underlying oxidative adaptations to interval training regimes. The relationship of exercise intensity with local blood supply and oxygen availability has not been sufficiently evaluated yet. The aim of this study was to examine the effect of six different intensities (40-90% peak oxygen uptake, VO2peak ) on relative changes in oxygenated, deoxygenated and total haemoglobin (ΔO2 Hb, ΔHHb, ΔTHb) concentration after exercise as well as end-exercise ΔHHb/ΔVO2 as a marker for microvascular O2 distribution. Seventeen male subjects performed an experimental protocol consisting of 3 min cycling bouts at each exercise intensity in randomized order, separated by 5 min rests. ΔO2 Hb and ΔHHb were monitored with near-infrared spectroscopy of the vastus lateralis muscle, and VO2 was assessed. ΔHHb/ΔVO2 increased significantly from 40% to 60% VO2 peak and decreased from 60% to 90% VO2 peak. Post-exercise ΔTHb and ΔO2 Hb showed an overshoot in relation to pre-exercise values, which was equal after 40-60% VO2peak and rose significantly thereafter. A plateau was reached following exercise at ≥80% VO2peak . The results suggest that there is an increasing mismatch of local O2 delivery and utilization during exercise up to 60% VO2peak . This insufficient local O2 distribution is progressively improved above that intensity. Further, exercise intensities of ≥80% VO2peak induce highest local post-exercise O2 availability. These effects are likely due to improved microvascular perfusion by enhanced vasodilation, which could be mediated by higher lactate production and the accompanying acidosis.

Delayed recognition of haemodynamically relevant congenital heart disease.

UNLABELLED: Delayed recognition of congenital heart defects may have a serious impact on the long-term outcome of the children affected. It was the aim of the present study, to evaluate the proportion of children with delayed cardiac diagnosis out of a large cohort of consecutive paediatric patients requiring treatment for congenital heart disease. A prospective study was performed over a 3-year period. Of all 323 paediatric patients requiring surgical (n = 291) or catheter interventional (n = 32) treatment for congenital heart disease, patients with delayed diagnosis of their cardiac defects were observed and especially examined for the presence of clinical cardiac findings other than systolic murmurs, not recognized as such prior to referral. Of all the patients, 32 (10%) had delayed diagnosis of heart defects. Surprisingly, the proportion of late diagnoses was not different in the group of patients with cyanotic heart disease where 7/72 patients were referred with delay, compared to 25 delayed referrals among 251 children with acyanotic heart defects. Of the 32 patients with delayed diagnosis, 7 had complications due to delayed referral, but there was no mortality associated with late diagnosis. CONCLUSION: A substantial proportion of all paediatric patients requiring intervention for heart disease were diagnosed with relevant delay. In all study patients with late diagnosis, clinical cardiac findings other than systolic murmurs were present that should have alerted the physician on the possible presence of underlying heart disease.

[Nonsurgical occlusion of an atrial septal defect in childhood: initial Swiss experiences]. / Nichtchirurgischer Verschluss eines Vorhofseptumdefektes im Kindesalter: erste Schweizer Erfahrungen.

The initial experience with catheter closure of an atrial septal defect (ASD) in children, performed at two Swiss centers is presented. The ASD closures were performed according to international multicenter study protocols. 14 children, aged 3.9-17.5 years underwent closure by catheter. The defect size varied between 12 and 22 mm (balloon sized), the ratio between pulmonary and systemic blood flow showed a mean of 2.2 (1.5-3.5). Catheter closure was done using three different occlusion devices. More recently only the Amplatzer occluder was used at both institutions. In 12 children (86%) defect closure was successful and after a follow-up of 3-32 months (mean 17) only one child had a trivial residual interatrial shunt. In all children, echocardiographic follow-up showed an unchanged and correct device position on both sides of the atrial septum. In two children, a floppy aortic segment of the atrial septal rim led to instable device position: both children underwent surgical defect closure later. The children with successful device closure showed no complications during the catheterization or during follow-up. There were no thrombotic complications on the surfaces of the devices. Catheter closure of an ASD during childhood is a safe and efficient alternative to standard surgical treatment.

Crystal structures of a family of silver cyanide complexes of thiourea and substituted thioureas.

The syntheses and crystal structures of a family of silver cyanide complexes of thiourea and substituted thioureas are reported. The sulfur ligands include thiourea (tu), 1-methyl-2-thiourea (mtu), 1,3-dimethyl-2-thiourea (dmtu), 1,1,3,3-tetramethyl-2-thiourea (tmtu), and 2-imidazolidinethione (N,N'-ethylenethiourea, etu). Synthesis was effected by dissolving AgCN in an aqueous solution of ligand. Two different complexes were obtained by the reaction of AgCN with tu. Complex 1a: (AgCN)(tu), monoclinic, P2(1)/c, a = 9.3851 (6) A, b = 8.2782 (5) A, c = 7.1178 (5) A, beta = 94.591 (1) degree, and Z = 4. Complex 1b: (AgCN)(tu)2, triclinic, P1, a = 7.9485 (14) A, b = 9.431 (2) A, c = 12.771 (2) A, alpha = 85.695 (3) degrees, beta = 81.210 (4) degrees, gamma = 77.987 (2) degrees, and Z = 4. Complex 2: (AgCN)(mtu), triclinic, P1, a = 4.113 (2) A, b = 9.472 (4) A, c = 9.679 (4) A, alpha = 113.918 (5) degrees, beta = 98.188 (6) degrees, gamma = 97.725 (6) degrees, and Z = 2. Complex 3 (AgCN)2(dmtu)2, monoclinic, P2(1)/m, a = 7.1482 (7) A, b = 14.776 (2) A, c = 7.3366 (7) A, beta = 92.418 (2) degrees, and Z = 2. Complex 4: (AgCN)(tmtu), orthorhombic, P2(1)2(1)2(1), a = 8.823(6) A, b = 10.209 (2) A, c = 10.362 (2) A, and Z = 4. Complex 5: (AgCN)2(etu)2, triclinic, P1, a = 6.8001 (2) A, b = 8.6154 (1) A, c = 13.4747 (3) A, alpha = 71.720 (1) degree, beta = 79.906 (1) degree, gamma = 75.885 (2) degrees, and Z = 2. All of the structures involve either one- or two-dimensional polymeric arrays held together by bridging S and CN groups. There is, however, no similarity between any two of the arrays. Four of the five ligands used also form similar complexes with CuCN. For one ligand, tmtu, the structures are isomorphous. For the other three, not only are the structures not isomorphous, the m/n ratio in (MCN)mLn when M is Ag is different from that when M is Cu.

Surgery of the complete atrioventricular canal: relationship between age at operation, mitral regurgitation, size of the ventricular septum defect, additional malformations and early postoperative outcome.

The perioperative risk after repair of the complete atrioventricular canal is reported to be low provided there is a balanced relationship of both ventricles, and elevated pulmonary vascular resistance has been demonstrated to be reversible. However, some pre- and perioperative conditions may adversely affect early postoperative outcome. A consecutive series of 42 patients (mean age 8.5 months, 34/42, 81%, with trisomy 21) operated between 1994 and 1998 was analyzed prospectively for pre- and perioperative risk factors. Echocardiography alone was performed in 35 patients whereas cardiac catheterization was performed in 7 patients aged more than 18 months to confirm operability. Additional malformations were found in 20 patients. Early mortality was 2.3% (1/42), and postoperatively a low cardiac output was observed in 25 patients (59%); NO inhalation was used in 12 patients. Only the size of the ventricular septal defect (> than the diameter of the aortic annulus) could be identified as a predictor of adverse postoperative outcome in multivariate analysis. The presence of associated intracardiac malformations showed a trend to increased perioperative risk in multivariate analysis. Early results after repair of the complete atrioventricular canal are excellent. Survival, postoperative morbidity and normalization of pulmonary artery pressure can be related to the size of the ventricular septal defect. Continuous monitoring of the pulmonary artery pressure (with consequent NO application when indicated) is probably responsible for the low perioperative risk encountered in this series, despite the high incidence of postoperative pulmonary artery hypertension.

Pediatric open heart operations without diagnostic cardiac catheterization.

BACKGROUND: Echocardiography allows for an adequate noninvasive preoperative evaluation in an increasing proportion of pediatric patients before open heart operations. The present study assessed the diagnostic accuracy of both invasive and noninvasive preoperative evaluation in children with congenital heart disease. METHODS: We prospectively evaluated the accuracy of preoperative noninvasive or invasive diagnostic methods. Preoperatively established diagnosis was compared with the intraoperative diagnosis made by surgical inspection and routine perioperative transesophageal echocardiography. RESULTS: During the study period of 30 months (ending in December 1997) 209 open-heart procedures were performed. Eighty-one patients (39%) were in the first year of life at the time of surgery, and 43% of all patients had symptoms. Noninvasive preoperative diagnosis using echocardiography was done exclusively in 142 patients (68%). Of the 67 children who had preoperative catheterization, 4 (6%) showed an additional intraoperative finding that modified the surgical approach in 2 of them. In the 142 patients who had echocardiographic preoperative assessment, the surgeons were confronted with a previously undiagnosed finding in 12 patients (8.5%). The finding was considered significant (prolongation of cardiopulmonary bypass time) in 2 patients and might have affected the outcome in 1 of them, a neonate with transposition of the great arteries and a preoperatively undiagnosed intramural coronary artery, who died postoperatively despite a technically adequate repair. CONCLUSIONS: In many infants and children, diagnostic work-up before open heart operations could be adequately based on an exclusively noninvasive basis by relying on echocardiography alone.

Quantitative echocardiographic characterization of abdominal aortic pulsatility in children with coarctation.

Obstructed blood flow due to aortic coarctation leads to a pressure drop and loss of the pulse wave distal to the stenosis. This can be observed by echocardiography as typically decreased pulsatility of the abdominal aorta after cardiac systole. Our study intended to quantitatively describe abnormal abdominal aortic pulsatility in children with coarctation. A standardized M-mode echocardiographic study of the abdominal aorta was prospectively performed with measurements of minimum and maximum abdominal aortic diameters and the corresponding time intervals during the cardiac cycle. Of these measurements the percent increase in aortic diameter was calculated and this increase was indexed to a unit of time. A total of 50 children were studied: 27 had angiographically proven severe coarctation (19 unoperated and 8 operated children with recurrent coarctation) with a mean minimum aortic lumen of 32+/-6% of the prestenotic aortic lumen. A total of 23 healthy children were studied as a control group. Children with significant coarctation differed from normals in all parameters evaluated. Two calculated values, the percent increase in aortic diameter (5-25% in patients and 27-50% in normals) and the percent increase per unit of time (18-108%/s in patients and 154-288%/s in normals) allowed for a clear discrimination between patients and normals with no overlap of individual values. Quantitative characterization of abnormal pulsatility of the abdominal aorta due to the loss of pulse wave pressure clearly discriminated children with angiographically proven significant coarctation from normal controls.

Troponin-I for prediction of early postoperative course after pediatric cardiac surgery.

OBJECTIVES: It was the aim of the study to test the prognostic value of cardiac troponin-I (cTnI) concerning the early postoperative course after pediatric cardiac surgery. BACKGROUND: Cardiac troponin-I is a very specific and sensitive marker of myocardial damage in adults and children. As perioperative myocardial damage may be a significant factor of postoperative cardiac performance, serial cTnI values were analyzed in children undergoing open heart surgery. METHODS: Seventy-three children undergoing elective correction of congenital heart disease including atrial and ventricular surgical manipulation were studied. Cardiac troponin-I levels were measured serially and correlated with intra- and postoperative parameters (such as doses and length of inotropic support, renal and hepatic function, duration of intubation). Patients with prolonged postoperative recovery were analyzed with special attention to the cTnI levels. RESULTS: The cutoff point for the definition of a high and a low risk group of cTnI values was set at 25 microg/liter, 4 h after admission to the intensive care unit (ICU) and at 35 microg/liter considering the maximal value of cTnI in the first 24 h in the ICU. The results showed a highly significant correlation between the need for inotropic support, the severity of renal dysfunction and the duration of intubation in relation to the serum levels of cTnI. CONCLUSIONS: Cardiac troponin-I serum levels after open heart surgery in children and infants 4 h after admission to the ICU allowed anticipation of the postoperative course and correlated with the incidence of significant postoperative complications.

[Atenolol for preventing recurrence of atrioventricular reentry tachycardia in childhood]. / Atenolol zur Rezidivprophylaxe von atrioventrikulären Reentrytachykardien im Kindesalter.

BACKGROUND: Supraventricular reentrant tachycardias are the most common cardiac arrhythmia observed in infancy and childhood. The often benign clinical course of the disease warrants careful selection of any antiarrhythmic drug given to prevent recurrencies, in order to avoid potentially dangerous side-effects such as proarrhythmia. This study reports our experience with atenolol in the longterm treatment of infants and children with supraventricular tachycardias. PATIENTS AND METHODS: A search of our database was made and all the children admitted in our institution between 1987 and 1995 for treatment of supraventricular tachycardia were selected. Patients who had longterm oral treatment with atenolol were retrospectively evaluated and were seen during 1996 in our outpatient clinic for a follow-up examination including a Holter-monitor. RESULTS: 14 infants and children with a median age of 2 9/12 years at first presentation could be evaluated. In 10 patients, atenolol was the first antiarrhythmic drug given. In 10 of the patients (72%) therapy with atenolol was considered successful and no further attacks of tachycardia occurred. In 2 patients a partial response to atenolol was seen with an important decrease in the frequency of tachycardias. Two patients showed no effect of treatment and the betablocker was withdrawn. The effect of the drug on heart rate and blood pressure was mild and did not lead to symptoms. In no case had the drug to be withdrawn for adverse effects. After a mean follow-up of 50 months (3-105 months), 7 patients were off the drug and free of recurrencies while among the 5 children still on atenolol, only one experienced rare episodes of tachycardia. CONCLUSION: Atenolol is efficient in the longterm treatment of supraventricular tachycardias and due to its favorable risk profile can be recommended as first line treatment option.

[Status and after-care of young adults with congenital heart defects]. / Zustand und Nachbetreuung von jungen Erwachsenen mit angeborenem Herzfehler.

INTRODUCTION: We studied patients with congenital heart defects born in 1975 and followed by our institution. We were interested in the outcome of these patients at the age of 20 years with regard to professional status, physical activity and psychosocial aspects. Furthermore, we investigated the handover from the paediatric to the adult cardiologist as well as the information level concerning antibiotic prophylaxis against bacterial endocarditis. METHODS: From a previous follow-up study to the age of 16 years, we knew 224 patients with congenital heart disease born in 1975, 119 were considered to need further cardiological follow-up. In 112 (94%) we have a complete follow-up to the age of 20 years with a structured interview by phone. RESULTS: Mortality and medical care during the period between 16 and 20 years of age were at a lower level than in the previous periods. Except in patients suffering from complex or surgically treated cyanotic heart disease, the results, compared to the standard population at the age of 20 years, are better with regard to professional status, and equal for physical activity and psychosocial integration. Only 60% of the patients were followed by an adult cardiologist and only 45% of the patients needing antibiotic prophylaxis against bacterial endocarditis are aware of this. CONCLUSION: Except in patients with complex congenital or surgically treated cyanotic heart diseases, the outcome at the age of 20 years with regard to professional status, physical activity and psychosocial integration is very good compared with the standard population at the age of 20 years. The handover to the adult cardiologist is inadequate and knowledge and awareness of antibiotic prophylaxis against bacterial endocarditis is also insufficient-both aspects need improvement.

Results of a restrictive use of antiarrhythmic drugs in the chronic treatment of atrioventricular reentrant tachycardias in infancy and childhood.

Childhood supraventricular tachycardia (SVT) carries a good prognosis. Thus, treatment should be based on the use of drugs with a low risk of such potentially serious side effects as proarrhythmia, which is well documented for class I and III drugs in children. We studied all pediatric patients with a first manifestation of SVT between 1988 and the end of 1995 who were seen for a follow-up examination, including Holter monitoring, during 1996. The minimum follow-up period was 12 months. Fifty children met study entry criteria. Mean patient age at first presentation was 2 years (median 1 month), with 33 of the patients (66%) having experienced their first episode of tachycardia in their first year of life. Of 39 patients initially treated with either digoxin or a beta blocker, SVT in 29 (75%) responded favorably to this treatment. There were no adverse effects. Of the 10 children whose disease did not respond to these first-line agents, 9 (23% of those treated) required class I or III antiarrhythmic drugs. Thus, first-line antiarrhythmic long-term prophylaxis using drugs with a favorable risk profile, such as digoxin and beta blockers, resulted in successful disease management in a large proportion of unselected children, avoiding the need for chronic use of class I or class III antiarrhythmic drugs.

Re-entrant supraventricular tachycardia in infancy: current role of prophylactic digoxin treatment.

UNLABELLED: Re-entrant supraventricular tachycardia is the most common cardiac arrhythmia in infancy. Pharmacological prevention of recurrencies is a standard recommendation for infants less than 1 year of age. In view of the often benign spontaneous clinical course of the disease, the risk-benefit analysis of any antiarrhythmic agent given is important. It was the aim of this retrospective study, to assess the value of oral long-term digoxin given to paediatric patients with supraventricular tachycardia with onset in the first 4 months of life. Twenty-six newborns and infants fulfilled the inclusion criteria. Median age at first presentation of the patients was 7 days. Eight patients (31%) had structural heart disease, 9 patients had a pre-excitation syndrome, and the other 17 children had a concealed accessory atrioventricular pathway. Long-term prophylaxis with oral digoxin was considered successful in 17 children (65%). In 2 patients therapy with digoxin was considered partially effective and in 7 patients (27%) failure of digoxin to improve symptoms led to the introduction of other anti-arrhythmic agents. Serum digoxin levels were no different in the patients with successful therapy as compared to those with treatment failure. No side-effects due to digoxin were noted in all the patients treated. After a mean followup of 54 months (12-130 months), 19 children (73%) were free of recurrencies and on no medication, 5 children were free of recurrencies but had anti-arrhythmic therapy. Only 2 patients, both on anti-arrhythmic therapy, were still suffering from tachycardia. CONCLUSION: Digoxin remains an effective treatment option in infants with supraventricular tachycardia and it helped to avoid the long-term use of other anti-arrhythmic drugs with potentially more serious side-effects (pro-arrhythmia) in a considerable proportion of infants treated.

Comparison of troponin-I and troponin-T after pediatric cardiovascular operation.

BACKGROUND: Although the diagnostic value of troponin-T in childhood is documented, little is known about the significance of troponin-I. It was the aim of this study to compare the diagnostic value of troponin-I and troponin-T in children and newborns to assess the perioperative potential myocardial damage. METHODS: Forty-eight children, mean, 51+/-54 months (mean value +/-1 standard deviation) (range, 1 day to 204 months) undergoing cardiac operation were prospectively enrolled in the present study. Troponin-I, troponin-T, creatine kinase (CK), and the MB isoenzyme were measured before operation and postoperatively within 2 days. RESULTS: Postoperative values of troponin-I for children undergoing extracardiac operation were in the normal range. In children with interventions through the right atrium (n = 10) the mean value increase to 6.5+/-6.1 microg/L (range, 1.8 to 24.3 microg/L) and even to a mean of 29.9+/-21.1 microg/L (range, 7.5 to 90 microg/L) (p<0.01) in children with atrial and additional ventricular surgical approach (n = 23). Troponin-I was of equal specificity and sensitivity compared to troponin-T, excepted in patients with postoperative renal failure in whom troponin-T raised to false pathological results. CONCLUSIONS: For detection of perioperative myocardial damage troponin-I shows a higher specificity than CK-MB activity and CK-MB mass. The diagnostic value of troponin-I is similar to troponin-T, but compared with troponin-T, it has the advantage of not being influenced by renal failure.

Dilated cardiomyopathy and thrombo-embolism.

UNLABELLED: The purpose of this study was to investigate the incidence, outcome and prevention of thrombo-embolism in children with dilated cardiomyopathy. From 130 patients with dilated cardiomyopathy, 17 (14%) showed evidence of thrombo-embolism. Seven had initial cardiac thrombus, 7 exhibited initial embolus and in 3 thrombo-embolism was only diagnosed at autopsy. All 17 patients showed seriously impaired systolic function of the left ventricle with fractional shortening (FS) of 10 +/- 3%, range 5%-17%, as compared to those without thrombo-embolism with FS of 17% +/- 6%, range 5%-26% (P < 0.0001). Seven patients were treated with oral anticoagulants once thrombo-embolism had been diagnosed; one of them experienced a further embolic event as opposed to three out of four patients not treated with anticoagulants. CONCLUSION: All children with dilated cardiomyopathy and fractional shortening below 20% should be treated with prophylactic anticoagulative agents.

Troponin-T: improved diagnostic assessment of myocardial damage in childhood.

Troponin-T (cTnT) as a marker of myocardial damage is well established in adults, but not yet in children. cTnT was measured in 85 children (aged 1 day-204 months, mean 46 months). Twenty-five children were non-surgical patients, with possible myocardial damage suspected on clinical grounds. The other 60 patients had cardiac surgery leading to a defined myocardial damage. In these children, troponin-T (cTnT), creatine kinase activity (CK), creatine kinase-MB activity (CK-MB), and creatine kinase-MB-Mass (CK-MB-Mass) were measured preoperatively and 3-4 times during the first 55 postoperative h. Except in four children with probable preoperative myocardial damage, all troponin-T values were in the normal range (< 0.1 microg/l). All children with intracardiac surgery showed a postoperative increase in troponin-T. Children with extracardiac surgery of the great vessels showed no postoperative increase of troponin-T. For the assessment of myocardial damage, troponin-T was more specific and more sensitive than the other markers tested, troponin-T might significantly improve the diagnostic assessment of myocardial damage in children.