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Objectives. To report use of a novel mobile cardiac outpatient telemetry (MCOT) system for evaluation of children and adolescents with suspected cardiac arrhythmia. Design. Prospective data collection and retrospective analysis. Setting. All patients who received MCOT from The Children's Hospital at the Cleveland Clinic between 1/14/04 and 2/12/05 were screened. Patients older than 21 years and those with previously documented arrhythmia were excluded. Patients. Fifty-nine consecutive MCOT studies were performed. Five patients met exclusion criteria leaving 54 subjects (mean age 12.4+/−4.5 years; range 3.2–19.7 years; 46% male) for inclusion. Interventions. The MCOT system (CardioNet, USA) consists of a 3-electrode, 2-channel sensor that transmits wirelessly to a portable monitor. Monitors continuously store, analyze, and transmit the electrocardiogram through cellular and land telephone networks to a central station. MCOT was performed for 9–32 consecutive days (mean 24.5+/−7.4). Results. Twenty-one subjects (39%) did not experience symptoms during MCOT, yielding a diagnostic rate of 61% (N = 33). Of the 33 diagnostic studies, 9% (N = 3; mean age 16.9+/−0.6 years; range 16.2–17.3 years; 1 male) showed supraventricular tachycardia and 9% (N = 3; mean age 11.1+/−2.7 years; range 8.2–13.5 years; 1 male) showed supraventricular or ventricular ectopy. Minor skin irritation at sites of electrode placement was the only complication of MCOT (N = 5). Conclusions. MCOT is safe and useful for evaluation of children and adolescents with suspected arrhythmia, providing a diagnosis in 61% of subjects. The diagnostic yield of MCOT was superior to that expected from traditional event and Holter monitors in this pediatric population.

To evaluate whether transcatheter closure of secundum atrial septal defects (ASD) affected noninvasive electrophysiologic variables in children, we reviewed the pre-procedural and 1-year postprocedural electrocardiograms and Holter recordings of 18 consecutive children referred for ASD closure. Patients included in the study were a mean of 5.0 years old (SD 1.1) and weighed a mean of 17.9 kg (SD 4.1). ASDs had a mean diameter of 14.0 mm (SD 2.4) and average shunt ratio (pulmonary-to-systemic flow) of 2.1:1. One year after occluder device placement, 9 children (50%) had detectable residual shunts by transthoracic echocardiograms, but only 2 (11%) had shunts that were felt to be possibly significant. One or more fractured occluder legs were noted by chest roentgenogram in 15 patients (83%). Electrocardiograms at follow-up demonstrated improvement in right ventricular dilation in 4 of 7 patients, right atrial enlargement in 3 of 4 patients, and 1 degree atrioventricular block in 2 of 3 patients. Holter recordings showed a decreased incidence of accelerated atrial rhythm in 3 of 7 patients, prolonged junctional escape rhythm in 2 of 2 patients, and premature atrial contractions in 2 of 2 patients. No finding correlated with patient age, defect or occluder diameter, occluder leg fracture(s), or residual defects. These improvements in electrophysiologic abnormalities compare favorably with changes seen 1 year after surgical closure. In conclusion, placement of a transcatheter ASD device in children diminishes noninvasive electrophysiologic abnormalities at 1-year follow-up. By relieving hemodynamic stress caused by an ASD in childhood, a transcatheter device may prevent arrhythmia disturbance later in life.

To minimize procedural and fluoroscopic times and avoid the risks of vascular injury and pneumothorax, some investigators have advocated elimination of routine placement of a coronary sinus (CS) catheter during electrophysiological procedures. We hypothesized that expedient and reproducible CS catheterization could be performed with minimal patient risk by utilizing a femoral vein approach. Fifty consecutive patients referred for radiofrequency ablative procedures underwent attempted CS catheterization using a 6-French steerable, quadripolar catheter via a femoral vein. Procedures were performed utilizing single-plane fluoroscopy without contrast angiographic aid by operators experienced in the technique. Successful catheterization was defined by the attainment, in15 minutes, of a stable catheter position with the distal electrode at or beyond the lateral margin of the heart. Successful catheterization of the CS was achieved in 47 (94%) patients. Selective pacing of the left atrium without patient discomfort was possible in all, eliminating the need for a right atrial pacing catheter. The median time to successful catheterization was 1.4 minutes (range 0.3-14.7). Only six patients required5 minutes. The median fluoroscopic time required was 1.2 minutes (range 0.3-12.7). No clinical variable was predictive of catheterization failure or time to successful catheterization. No complications were observed as a result of this technique. This prospective evaluation demonstrates that catheterization of the CS via a femoral vein approach is highly successful, expedient, and safe. The ability to selectively pace the left atrium may eliminate the requirement for a right atrial catheter.

Generalized, extensive electrical repolarization abnormalities, represented by negative or abnormally peaked T waves, are frequently observed after radiofrequency catheter ablation of overt accessory atrioventricular (AV) connections in Wolff-Parkinson-White (WPW) syndrome. Two mechanisms have been proposed to explain these changes: subendocardial injury, secondary to the application of radiofrequency lesions, and memory T waves. The purpose of this study is to evaluate the electrocardiographic (ECG) changes in patients with overt and concealed accessory AV connections after ablation. Fifty-one patients with accessory AV connections who underwent successful radiofrequency ablation were included in the study. Twenty-four patients with clear, manifest, and permanent preexcitation (group 1) were compared with 27 patients with concealed accessory AV connections (group 2). Electrocardiograms were obtained in all patients before ablation, shortly after ablation (within 4 hours), and late after ablation (6 weeks). The frontal and horizontal QRS-T angles in the ECGs, number of lesions, total Joules applied, total peak creatine kinase, and total peak creatine kinase-MB units were compared in both groups. Of the 24 patients with overt accessory AV connections, 23 (95.8%) demonstrated repolarization abnormalities in the ECG shortly after the procedure that reverted almost completely at 6 weeks. Of the 27 patients with concealed accessory AV connections, only 2 (7.4%) demonstrated repolarization abnormalities after the ablation (P < .0001). The persistence of an abnormal QRS-T angle immediately after ablation in patients with overt accessory AV connections is caused by an abnormality in the T wave axis, opposite to the direction of the normal QRS axis.(ABSTRACT TRUNCATED AT 250 WORDS)

Heart-lung transplantation has been used successfully for patients with pulmonary vascular disease but its application has been very limited due to the scarcity of donors. We report a patient with Eisenmenger's syndrome who underwent right single-lung transplantation with closure of atrial septal defect; postoperative convalescence was uneventful. Serial magnetic resonance imaging examinations demonstrate improved right heart function.

Children and adults with cardiomyopathy and ventricular dysrhythmias have a uniformly poor prognosis, despite medical therapy. The use of automatic implantable cardio-defibrillators in adult patients with medically resistant ventricular dysrhythmias has resulted in a positive impact on survival. Because of its size and former lack of programmability, the device has been used rarely in children. Four patients with cardiomyopathy, in whom refractory ventricular dysrhythmias were managed with automatic implantable cardio-defibrillators, are presented. Two of these children are the youngest and smallest known in whom the device has been used; one of them received the first programmable model. The use of the automatic implantable cardio-defibrillator may enhance survival in selected young patients.

Focal atrial tachycardias originating from the left atrial appendage present unique anatomic challenges for successful ablation. We describe the role of minimally invasive percutaneous epicardial mapping and ablation in the management of two patients with ectopic atrial tachycardias arising from the left atrial appendage following failure of a conventional endocardial approach to achieve cure.

Congenital atrial septal defect repair is safe and effective in patients of almost any age. Long-term survival among adults is excellent, although children generally appear to fare even better. Our 25-year study of outcomes among adults who underwent suture or patch closure found that survival exceeded 90%. We discuss our observations on use of transesophageal echocardiography, indications for cardiac catheterization, and continuing questions about atrial septal defect in adults.

To evaluate right ventricular abnormalities with magnetic resonance (MR) imaging in patients with arrhythmia but without arrhythmogenic dysplasia.In 53 patients being evaluated for right ventricular arrhythmia and 15 control subjects, MR imaging was performed to evaluate fixed thinning, fatty replacement, or reduced systolic wall thickening or motion. A diagnosis of idiopathic right ventricular outflow tract tachycardia or indeterminate was assigned for each patient, and the severity of arrhythmia was categorized.Right ventricular abnormalities were revealed in 32 (60%) of the 53 patients: fixed thinning in 27 (84%), fatty replacement in eight (25%), and reduced wall thickening or motion in 31 (97%). Right ventricular abnormalities were found in 35 (76%) of 46 patients with idiopathic right ventricular outflow tract tachycardia and in seven (39%) of 18 patients with indeterminate diagnoses (P = .022).Mild right ventricular abnormalities are likely sources for arrhythmias, even in the absence of arrhythmogenic right ventricular dysplasia.

Bundle Branch Reentry VT with Two Morphologies. Introduction: Bundle branch reentry ventricular tachycardia (VT) is usually amenable to treatment with radiofrequency ablation. Different QRS morphologies during VT are possible when anterograde ventricular activation is over the left bundle branch. Manifestations of tbis reentrant tachycardia with more than one QRS morphology with anterograde activation via the right bundle have not been reported and would be unusual due to the more discrete anatomy of the right bundle branch. Methods and Results: An electropbysiologic study was conducted in a patient with dilated ventricle and diminished ventricular function with VT, Typical characteristics of bundle branch reentry were noted when VT was induced. The study was notable for the presence of a right bundle recording only during macroreentrant beats or VT and the distal location of the recording. Radiofrequency ablation was performed. Postablation stimulation again induced VT, proven to be of the same bundle branch reentry mechanism but of a different QRS morphology. A second ablation was required for complete ablation of this patient's bundle branch reentry VT. Conclusion: In bundle branch reentry utilizing the left bundle as the retrograde limb and the right bundle branch as the anterograde limb of the circuit, VT of more than one distinct morphology can be seen. Careful evaluation to assess for the persistence of VT of the same mechanism is necessary to ensure complete ablation of the reentrant circuit. Preexisting right bundle disease and a dilated heart with more dispersed distal right bundle branches may predispose to such a phenomenon.

BACKGROUND It is critical to repair atrial septal defects during childhood to minimize long-term morbidity and mortality. However, only a few studies have examined factors that predict a favorable outcome. OBJECTIVE To examine prognostic variables in the repair of atrial septal defects. METHODS Retrospective analysis of children who underwent repair of atrial septal defects between 1957 and 1981. RESULTS There were 70 girls and 57 boys with a mean age of 9.3 years at the time of surgery (range 4 months to 20 years). The most common presenting symptoms were fatigue and dyspnea. Before surgery, 74% were in New York Heart Association functional class I, 70% had echocardiographic evidence of right ventricular hypertrophy, and 55% had cardiomegaly on chest radiographs. The average mean pulmonary arterial pressure was 17.1 mm Hg. The only factor significantly related to poor outcome was pulmonary hypertension. Age at surgery did not influence long-term results. Ninety-four percent of patients were in functional class I at follow-up. CONCLUSIONS Repair of atrial septal defects is safe before age 21, but it should be done as early as possible in order to minimize the long-term complications of chronic left-to-right shunting.

Thirty-four young patients (28 male and 6 female) underwent aortic valve replacement between 1972 and 1988. Ages ranged from 11 to 20 years (mean 17.7 years). Including reimplantation in the follow-up period, 40 valves were implanted, among which were 17 (43%) St. Jude, 7 (16%) Bjork-Shiley, and 4 (10%) Carpentier-Edwards. Seven patients (18%) had tissue valve prostheses (4 Carpentier-Edwards, 3 Hancock valves). There was one hospital death (2.9%). Follow-up was obtained in 30 of the 33 hospital survivors, with a mean follow-up of 80 months. In the follow-up period, one patient (3%) had a major thromboembolic event and one patient (3%) had prosthetic valve endocarditis. Six patients (18%) required replacement of the implanted valve; three of these had received Hancock tissue valve prostheses. There were three late deaths, yielding 96% survival at 5 years and 84% at 10 years. Twenty-three of 30 survivors are currently New York Heart Association class I. Aortic valve replacement in young patients can be performed with low mortality and morbidity, and with excellent long-term results.

We reviewed autopsies in 50 consecutive cases of congenital heart disease between 1980 and 1988. Autopsy results were compared to premortem clinical diagnosis. The patients ranged in age from two days to 66.5 years with a mean age of 6.42 years; 68% were less than one year of age. The most common diagnoses were hypoplastic left heart syndrome in 16 (32%) and ventricular septal defect in five (10%). Other common diagnoses included coarctation of the aorta, hypoplastic right heart syndrome, tetralogy of Fallot, transposition of the great vessels and tricuspid atresia. No patient had a missed diagnosis that would have changed survival (Class 1). Four (8%) of the patients had one missed major diagnosis that did not change their survival because they were already being symptomatically treated or because no clinical treatment was available (Class 2). The majority of autopsy derived data were missed minor diagnoses that were related [14 (28%) - Class 3] or unrelated [12 (24%) - Class 4] to the terminal disease process. However, despite the small percentage of autopsy findings that would have directly affected survival, the autopsy provided important additional clinical information in 30 (60%) patients. This information could be used to correct management errors and to develop protocols for prophylaxis against known complications. The pediatric autopsy can provide useful clinical data that may be a guide to altering clinical therapy and is essential in providing genetic counseling.

The initial and long-term results of transcatheter electrical ablation in 29 patients with drug-refractory supraventricular tachyarrhythmias were analyzed. Ablation was immediately successful (defined as induction of chronic complete heart block) in 25 patients (86.2%). Among the group in whom ablation was unsuccessful, there were more patients with ectopic atrial tachycardia and a higher incidence of narrow QRS escape rhythm following the initial ablation. A His amplitude equal to or greater than 0.3 mV was correlated with success. Complications of ablation included deep venous thrombosis and ventricular arrhythmias. Post-ablation stress testing was superior to ambulatory monitoring in identifying early return of atrioventricular conduction.

Two hundred and eighty four patients with Down Syndrome (DS) were seen between 1951-1989 with 114 (40.1%) having a cardiac murmur at presentation. A definitive cardiac diagnosis was established in 47 (41%) patients, of which 38 had long term follow-up. Fifteen (33%) patients had atrioventricular canals. There were 21 males and 17 females, with a mean age of 5.3 years. Fifteen (39%) patients were in functional class (FC) I, 16 (42%) in FC II, six (15%) in FC III, and one patient in FC IV at the time of presentation. There were 18 survivors (13 in the surgical group and five in the nonsurgical group) and 20 nonsurvivors (four in the surgical group and 16 in the nonsurgical group). Causes of death in the nonsurgical group included congestive heart failure, pneumonia, and pulmonary vascular disease, and occured at a mean age of 8.4 years. Post-operative complications accounted for deaths in three of the four surgical patients. The survivors in the surgical group are presently in FC I/II. In the nonsurgical group, there was increased mortality, especially in those who presented in an earlier era, and a deterioration in functional class on follow-up due to the development of pulmonary vascular disease. Our data suggest that a) patients with Down syndrome and heart disease are helped by cardiac surgery with stabilization and improvement of their functional class; b) deterioration in functional class is seen in patients with Down syndrome with cardiac lesions who are managed surgically and c) mortality remains high in such patients treated nonsurgically due to development of pulmonary vascular disease and congestive heart failure. Therefore, early diagnosis and surgical correction where appropriate is a key issue in the management of children with Down syndrome.

The long-term prognosis of adult patients with patent ductus arteriosus treated medically or surgically has not been demonstrated. One hundred seventeen adult patients ranging in age from 18 to 81 years (mean 36) were followed up for 1 to 37 years (mean 18). Forty-five patients were treated nonsurgically and 72 had surgical closure. The nonsurgical group experienced significantly more cyanosis (p = 0.002) and had fewer diastolic murmurs (p greater than 0.001) than did the surgical group. In the nonsurgical group, patients with cardiomegaly before treatment were more likely to die (p greater than 0.001) than were patients who did not have cardiomegaly. In the surgical group, patients with cardiomegaly before treatment had a worse prognosis (p = 0.09) than that of patients with normal heart size. Seven patients, five in the nonsurgical and two in the surgical group, presented with a pulmonary artery systolic pressure greater than 100 mm Hg. Five of these patients are alive and well at a mean follow-up time of 18 years. The two nonsurvivors were in the nonsurgical group and died at 4 and 19 years of follow-up, respectively. Adult patients with patent ductus arteriosus should be treated surgically, especially if cardiomegaly is seen at initial presentation.

(1974). The Humanistic Wellspring of Psychoanalysis. The Psychoanalytic Quarterly: Vol. 43, No. 2, pp. 167-176.

Clinical features and natural history were analyzed in 30 patients with Ebstein's anomaly (mean age 26 years, range 1.5-58 years, 53% females). The main presenting symptoms were dyspnea and fatigue (83%). At presentation, there were six patients (20%) in New York Heart Association Functional Class (NYHAFC) I, nine (30%) in NYHA-FC II, and 15 (50%) in NYHA-FC III or IV; 12 patients (40%) were cyanotic. Common auscultatory findings were widely split second heart sound in 21 (70%), third heart sound in 14 (47%), fourth heart sound in 16 (53%), and a systolic murmur in 22 (73%). Right bundle branch block was present in 21 (70%), documented supraventricular tachycardia in seven (23%), and Wolff-Parkinson-White syndrome in three (10%). Catheterization was performed in 93% without complications. Fourteen patients were treated surgically (12 [86%] in NYHA-FC III or IV, 10 [71%] with associated anomalies); tricuspid valve replacement was performed in eight, atrial septal defect repair in two, accessory pathway ablation in two, right atrial plication in one, and automatic cardioverter defibrillator implantation in one. Surgical treatment improved 10 patients from NYHA-FC III or IV to NYHA-FC I or II. Death occurred in nine patients (five treated surgically and four medically); four of these deaths were sudden. In the eight patients who had tricuspid valve replacement, there were one operative and two late deaths. The authors conclude that surgical therapy with tricuspid valve replacement improves the clinical status of patients who are severely ill. Risk of sudden death remains an important problem in patients with Ebstein's anomaly regardless of severity of the disease and mode of treatment.

Digital subtraction angiography was performed in six patients suspected of having a vascular ring. There were four males and two females. Two patients were less than 6 months of age, two were between 14 and 20 months, and two were ages 4 and 53 years. Four of the six patients had abnormal esophagrams. Five patients underwent peripheral intravenous digital subtraction angiography and a sixth patient underwent digital subtraction angiography via arterial catheterization. In two patients (ages 20 months and 4 years), the presence of a vascular ring was excluded by demonstrating an anatomically normal arch with an anomalous right subclavian artery. In three patients, a right aortic arch was present. Two of these patients had mirror image branching and a left ligamentum arteriosum. The third patient had an aberrant left subclavian artery and a left ligamentum. One patient had an anomalous right subclavian artery and a systemic collateral vessel arising from the aorta, supplying a confluence of vessels in the right lung hilum. In all patients, anatomic definition was accurate with the intravenous injection and there were no complications. In the patient who underwent intra-arterial injection, the dose of contrast was reduced 50% from the dose usually administered. Digital subtraction angiography appears to be a good adjunctive diagnostic method in patients in whom the presence of a vascular ring needs to be confirmed angiographically and obviates the need for arterial catheterization.

In this case study we report a 59-year-old man who underwent combined aneurysectomy, endocardial resection, and cryosurgery for recurrent ventricular tachycardia. Following surgery he developed an accelerated junclional tachycardia with rates up to 190/min arising near the area of cryoablation which involved the junctional region. Using intracavitary recording and stimulation this tachycardia was shown to arise from ihe junctional area and had characteristics suggesting accelerated automaticity. During the electrophysiological study the focus of the tachycardia was temporarily obtunded by catheter trauma. After reappearance of the arrhythmia, successful suppression was achieved using diphenylhydantoin. (PACE, Vol. 5, May-June, 1982)

Thirty-four patients with preexcitation syndrome had surgical ablation of the accessory atrioventricular connection. All presented with sustained symptomatic arrhythmias, which had resulted in syncope in seven patients and aborted sudden cardiac death in four. Arrhythmias induced at electrophysiologic evaluation included orthodromic reciprocating tachycardia in 32 patients, antidromic reciprocating tachycardia in five patients, and atrial fibrillation in 29 patients. A single accessory atrioventricular connection was located in 32 patients and two patients had multiple accessory connections. The accessory connection was located with intraoperative mapping in all patients and the pathway was successfully ablated in 32. Eleven patients underwent a transmural approach and 23 patients underwent an epicardial dissection. Cryotherapy was used in 22 patients. After a mean follow-up of 32 months, 28 patients were free from all arrhythmias without drug therapy. Six patients continued to have symptomatic arrhythmias but only one case was suspected to be secondary to unsuccessful ablation of the accessory connection. One patient with heart block induced at the surgical procedure is dependent upon a pacemaker.

Twelve patients with evidence of Mahaim fibers are reported, six with nodoventricular (NV) fibers and six with fasciculoventricular (FV) fibers. All patients with NV fibers had left bundle branch block morphology, and a sustained reentrant tachycardia with this morphology was proved in each case. In three of the six, ventriculoatrial dissociation occurred during tachycardia. We postulate that the mechanism of this tachycardia is a macroreentry circuit using the NV fiber for the antegrade limb and the His-Purkinje system with a portion of the atrioventricular node for the retrograde limb. ECGs of patients with FV fibers were varied, suggesting a functional relation to the right or left side of the septum. No direct relationship of FV fibers to observed arrhythmias could be found.

Isolated partial anomalous pulmonary venous drainage with an intact atrial septum is a rare finding. The authors describe their experience with three patients (ages 9, 37, and 54 years), with partial anomalous pulmonary venous connection to the superior vena cava, right atrium, and inferior vena cava, who underwent extracardiac conduit repair of this anomaly. In all three patients, a synthetic Gortex graft was used for reconstruction of the venous pathways to the left atrium. The follow-up period ranged from 10 to 82 months (mean, 42 months). All three patients were evaluated with intravenous digital angiography, transesophageal echocardiography, or both at 10, 33, and 82 months postoperatively. Patency of the grafts with no evidence of obstruction and excellent pulmonary venous flow was shown. This surgical technique is an excellent option for correction of this anomaly, and intravenous digital subtraction angiography is a useful diagnostic tool during the postoperative period to evaluate patency of the repair.

The authors describe the use and advantages of percutaneous balloon angioplasty to treat pulmonary valve stenosis.

Between the years 1928 and 1932, Sigmund Freud occasionally assembled a small group of members of the Vienna Psychoanalytic Society for scientific discussions. These informal meetings took place on Wednesday evenings at Freud's home. The author reports what he was able to preserve of Freud's remarks on some of these occasions.

A retrospective analysis was undertaken to define the natural history and long-term follow-up of a group of patients with Marfan's syndrome. Eighty-four patients were diagnosed between January 1959 and June 1987 as having Marfan's syndrome; 68% were male; their ages ranged from 2 to 67 years (mean 26.6). Sixteen patients constituted the early surgical group (those who underwent surgery before 1979; mean age 36.1 years). Nineteen patients constituted the late surgical group (surgery in 1979 or later; mean age 33.3 years). The nonsurgical group comprised 49 patients (mean age 19.3 years).Fifty-seven percent of the patients had a diastolic murmur and 38% had cardiomegaly at presentation. Fiftyseven percent underwent cardiac catheterization, which revealed aortic root dilation (85%), aortic regurgitation (73%), aortic dissection (33%) and mitral regurgitation (36%). Thirteen of the 19 patients in the late surgical group received a composite graft repair of the ascending aorta as compared with only 2 of the 16 in the early surgical group.Follow-up information was obtained on 81 (96%) of 84 patients; the follow-up time was 2 to 332 months (mean 99). Thirty-one of the 81 patients died at age 3 to 63 years (mean age 35 years); 87% of the known causes of death were related to the cardiovascular system. Sixty-one percent of deaths were the result of aortic dissection or rupture or sudden cardiac death. Of the 50 survivors, 98%, including all patients in the late surgical group, were in functional class I or II. Overall survival at 5, 10 and 15 years after operation was 78.4%, 57.1% and 49.5%, respectively. The presence of a diastolic murmur or cardiomegaly, or both, at presentation was associated with poor prognosis, which can be attributed to aortic insufficiency.There was a definite improvement in survival of patients operated on in 1979 or later as compared with survival of patients in the early surgical group (87.5 % survival at 5 years versus 56%, respectively). The improved survival in the late surgical group is attributable to earlier and more extensive surgery utilizing a composite graft with reimplantation of the coronary arteries as the procedure of choice.

We have carried out a quantitative analysis of the force-interval relationship of the human left ventricle and compared it to previous studies done in both intact subjects as well as isolated muscle. The characteristics of the force-interval relationship of the normal patient resembed those of normal isolated mammalian muscle (except when exposed to high levels of catecholamines). The relationship in group 2 (patients with increased left ventricular dimensions and normal pressure indices) resembled those obtained from isolated muscles from hypertrophied hearts. The relationship from group 3 (patients with increased left ventricular EDDs and depressed pressure indices, two of whom were in clinical heart failure) resumbled those induced in normal muscles exposed to high levels of catecholamines, and those obtained from experimentally induced heart failure. The force-interval relationships of the four patients who fell into the third group were strikingly different from the other groups. This suggests that the force-interval relationship may be useful to describe changes in the inotropic state of the patient's heart.

Pre- and postoperative structural changes and pulmonary to systemic flow (QP/QS) ratios were assessed using digital angiography in 34 patients documented to have a left to right shunt at cardiac catheterization. There were 16 men and 18 women whose ages ranged from 4 months to 60 years. The radiographic single mask mode was used for all digital subtraction angiographic studies with a typical radiographic sequence being 80 to 100 kV, 5 to 10 mA/frame at six frames/s for 15 seconds. Renografin-76 was used as a bolus injection at 0.5 to 1.0 ml/kg via an arm vein in most patients. The level of the left to right shunt and any associated anomalies were noted and compared with results from cardiac catheterization. Digital subtraction angiographic flow curves were generated from the pulmonary arteries, and QP/QS ratios were calculated pre- and postoperatively using the gamma variate fit method and compared with the QP/QS ratio from first pass radionuclide studies.A strong correlation between preoperative digital subtraction angiographically derived QP/QS ratio and radionuclide-derived QP/QS ratio was found, with an r value equal to 0.89, p < 0.0001. Postoperatively, all patients had a QP/QS ratio less than 1.2:1.0 for both digital subtraction angiography and radionuclide studies. The level of left to right shunt was accurately assessed in all patients, and its absence observed postoperatively. Associated anomalies, such as a persistent left superior vena cava, coarctation of the aorta and partial anomalous venous return, were identified in all cases.Intravenous digital subtraction angiography provides accurate quantitative and anatomic data in patients with a left to right shunt, is potentially an important outpatient method to assess adequate surgical correction and may suffice preoperatively to proceed to cardiac surgery without preoperative cardiac catheterization.

Forty-nine patients with Wolff-Parkinson-White syndrome, ages 7 weeks to 51 years, were studied with isopotential body surface maps during normal sinus rhythm, atrial pacing or induced atrial fibrillation. The location of the accessory pathway was determined by multicather electrophysiologic study or surgical ablation of the accessory pathway. When fusion was minimized and ventricular activation primarily controlled by a single accessory pathway, the distribution of positive and negative potentials on the anterior and posterior torso during QRS (observed at 40 msec) and the ST segment were an excellent index of the location of the site of the accessory pathway. The relationship between a specific sequence of QRS-T wave body surface maps and a specific preexcitation site was similar from patient to patient in the presence of marked differences in age, size, and different cardiac status due to structural congenital cardiac defects. The localization of the site of the accessory pathway using distributions too early in QRS (before 40 msec) was unreliable because the early distributions varied from patient to patient for the same preexcitation site; however, the potential distributions during the ST segment were both stable and consistent from patient to patient for the same preexcitation site. The presence of significant fusion of ventricular activation initiated via a single accessory pathway and the normal conduction system or via multiple accessory pathways complicated the interpretation of body surface distributions. Thus, one can predict accurately at least seven preexcitation sites by the combined use of QRS and ST-segment body surface maps.

Twenty-two patients with Ebstein's anomaly were evaluated because of recurrent tachycardia. A total of 30 accessory pathways were present in 21 of the 22 patients. Twenty-six accessory pathways were of the atrioventricular (A-V) type while four were Mahaim fibers. Multiple accessory pathways were present in eight patients. Twenty-five of the 26 accessory A-V pathways were right-sided, either in the posterior septum (12 pathways) or the posterolateral free wall (13 pathways); one patient with corrected transposition of the great arteries had a left-sided accessory A-V pathway in a lateral free wall location. Patients with accessory A-V pathways had a long minimal ventriculoatrial (V-A) conduction time during reciprocating tachycardia (192 +/- 47 ms) and usually showed a persistent complete or incomplete right bundle branch block morphology. At surgery, preexcitation was invariably localized to the atrialized ventricle. The long V-A conduction time during reciprocating tachycardia appeared to consist of late activation of the local ventricle in the region of the accessory pathway with a further delay occurring before excitation of adjacent atrium presumably due to conduction over the accessory pathway. Accessory A-V pathways were successfully sectioned with no deaths in 13 of 15 patients. On the basis of these data, certain electrocardiographic findings encountered in the study of patients with recurrent tachycardia should point to the possibility of associated Ebstein's anomaly: morphology of the surface electrocardiogram suggesting preexcitation of the right posterior septum or right posterolateral free wall as well as the combination during reciprocating tachycardia of a long V-A interval and right bundle branch block.

From February, 1983, to November, 1984, 11 infants with hypoplastic left heart syndrome were managed medically prior to operative intervention. Only 2 of the 11 infants appeared to be in mild distress at birth. Despite relatively normal Apgar scores, 9 of the infants were seen in shock. All patients were managed medically with fluid restriction, diuretics, and the institution of prostaglandin E1. There was a marked improvement in arterial pH from a mean value of 7.13 prior to prostaglandin to 7.42 following prostaglandin infusion. There was also a dramatic decrease in the serum creatinine level from a mean pretreatment level of 1.5 mg/dl to 0.7 mg/dl following infusion. Ten of the 11 infants were operated on at a mean age of 4 days with a Norwood or conduit procedure. Three infants who died at 3, 13, and 24 days of age had sustained myocardial infarctions prior to operation. Three patients also had multiple infarcts of the liver. Three patients are alive 23, 22, and 6 months after operation, and are growing and developing normally. The ability to maintain the infant with hypoplastic left heart syndrome in a stable hemodynamic condition has made surgical palliation a realistic option for this otherwise fatal anomaly. Nevertheless, preoperative infarctions of the heart and viscera continue to play a major role in mortality.

Patients with hypertrophic cardiomyopathy (HC) have a high risk of sudden death. The best clinical predictors of sudden death from HC are young age, strong family history of sudden death, ventricular tachycardia (VT), and progression of symptoms such as syncope. We performed 24-hour Holter monitoring and electrophysiologic studies (EPS) on 26 patients with HC, some with the obstructive form of the disease and some with syncope, in order to predict their vulnerability to syncope and to potentially malignant arrhythmias. Holter monitoring demonstrated supraventricular tachycardia (SVT) in 9/26 patients whereas atrial programmed electrical stimulation induced SVT in 17/26 patients. Of the 17 patients, nine had symptomatic hypotension with SVT while lying supine. Holter monitoring demonstrated nonsustained VT in 7/26 patients whereas ventricular programmed electrical stimulation induced VT or ventricular fibrillation (VF) in 6/26 patients. The patient who had the longest run of nonsustained VT on Holter had VF induced by ventricular programmed electrical stimulation. He was cardioverted to normal sinus rhythm with no untoward effects. We found that atrial programmed electrical stimulation induced SVT with hypotension best predicted a history of syncope in these patients. Although one patient required direct current cardioversion, EPS was conducted safely in all patients. Further long-term studies are needed to demonstrate the value of clinical decisions based upon EPS in patients with HC.

To evaluate subsidiary ventricular pacemaker function in 20 children with congenital or surgically induced complete heart block, we measured recovery times following overdrive ventricular pacing. Long-term ECG tape recordings were performed in eight of these children. Ages ranged from 1 month to 17 years. The resting R-R intervals ranged from 595 to 1,740 msec. The ventricles were paced at various cycle lengths of 400 to 1,000 msec with either transvenous electrode catheters or surgically implanted epicardial electrodes. His bundle recordings showed that the site of block did not allow separation of patients with symptoms from those without symptoms. Prolonged recovery times were present in patients with block above the His bundle recording site who had symptoms of syncope or dizziness, as well as in patients who had a wide QRS. However, some asymptomatic patient with heart block above the His bundle recording site also had long recovery times. None of the asymptomatic patients who had ECG tape recordings had paroxysmal tachycardia in more than 300 hours of recordings. However, one symptomatic patient with congenital heart block and a prolonged recovery time had brief episodes of paroxysmal ventricular tachycardia that produced no symptoms at the time of recording. The results suggest that the coexistence of prolonged recovery times and paroxysmal tachycardia may be predisposing factors to the development of symptoms in patients with complete heart block. We believe that further electrophysiologic investigation of this possibility is warranted in patients with heart block.

Sixteen patients with tetralogy of Fallot were studied with intravenous digital subtraction angiography (DSA). Of these, 11 were males and five were females, ranging in age from 26 months to 54 years, with a mean age of 22 years at the time of the initial study. Twenty-two DSA studies were performed in the 16 patients, in seven patients preoperatively, in 12 patients postoperatively, and in three patients both pre- and postoperatively. In the seven patients studied preoperatively, all DSA studies were considered technically adequate as corroborative evidence in the diagnosis of tetralogy of Fallot. All associated cardiac abnormalities were adequately demonstrated. The 16 postoperative studies on 12 patients were performed to evaluate the adequacy of the surgery and/or postoperative complications. These studies were judged as technically satisfactory. The authors utilized intravenous DSA in the pre- and postoperative evaluation of 16 patients with tetralogy of Fallot and found that reliable angiographic information was provided and that this technique may serve as a useful adjunct with other noninvasive and invasive tests in the preoperative and postoperative evaluation of these patients.