Haemodynamic and echocardiographic findings after aortoventriculoplasty.

Aortoventriculoplasty (AVP) is an established operative procedure for the enlargement of different types of severe left ventricular outflow tract obstruction. Between 1974 and 1985 75 aortoventriculoplasties were carried out in 72 patients ranging from 5 to 34 years of age. Three patients had to be reoperated upon due to significant right ventricular outflow tract obstruction, outgrown prosthesis, and dissecting aortic aneurysm. There were 7 early deaths (mortality rate 9.3%) and one late death (1.3%) following AVP. Out of the last 55 patients only 2 died (3.6%). In contrast to the unsatisfactory haemodynamic results of previous conventional operations. AVP reduced the mean residual gradient at rest across the left ventricular outflow tract from 84 +/- 23 mmHg (range 50-160 mmHg) to 12 +/- 12 mmHg (range 0-65 mmHg). Except in 2 patients, no gradient increased more than 15 mmHg with isoproterenol. In the cross-sectional echocardiogram, the left ventricular outflow tract was enlarged from 1.9 +/- 0.42 to 3.1 +/- 0.39 cm after AVP, whereas the aortic annulus had been expanded from 2.4 +/- 0.36 to 3.2 +/- 0.35 cm (n = 17). The mean length of the inner patch covering the septal incision measured 2.1 cm +/- 0.4 cm (n = 37). Our recatheterization studies after AVP revealed equally good haemodynamic results in all types of left ventricular outflow tract obstruction which cannot be relieved by conventional surgery.

The durability of bioprostheses in young people. Long-term results with intra- or extracardiac implanted porcine valves.

Forty two children and two young adults who were long term survivors of either intracardiac or extracardiac valve replacement with glutaraldehyde porcine valves form the basis of this report. The follow-up period varied from 6 months to 9 years. Ten of eleven intracardiac valves developed some dysfunction--the eleventh patient died from other causes. Of a total of 36 extracardiac valved conduits in the Rt side of the heart, four have needed replacement and an additional four will require replacement in due course. The probability of an event free performance of an intracardiac porcine valve is zero at 5 years. Four extracardiac valves there is in an 80% expectancy at 5 years and a 12% at 8 years of trouble free existence.

The preoperative and postoperative findings in 627 patients with tetralogy of Fallot.

The preoperative and postoperative findings in 627 patients operated for correction of tetralogy of Fallot (TOF) in the period 1960 to 1984 were analyzed in order to evaluate the clinical and hemodynamic late results. The average age was 7.2 years (range 9 months to 30 years). The patients were divided into 4 groups in order to determine the long-term prognosis in relation to the severity of the underlying anatomy; group I = without outflow tract patch; group II = with a patch up to the valve base; group III = with a transannular patch (TAP); group IV = TAP or valved conduit in patients with pulmonary atresia. Preceding shunt operations had been performed in 350 patients (55.8%); a primary correction was carried out in 277 cases (44.1%). Hospital mortality for all patients operated from 1960 to 1984 was 14.0%, late mortality, by contrast, was only 1.1%. In the last 4 years (1980 to 1983), the overall mortality considerably decreased to 3.4% (n = 29) for patients without TAP and to 8.0% for all operated patients including those with pulmonary atresia (n = 50). A comparison of the actuarial survival curves, moreover, demonstrates that the prognostic survival rate is unequivocally dependent on the severity of the anatomy of a TOF. The hemodynamic results obtained from 271 recatheterized patients from all 4 groups were designated excellent in 106 patients (39.1%), good in 100 (39.9%) and poor in 65 (23.9%). Proximal residual gradients across the right ventricular outflow tract (RVOT) were found in 30.2% of the corrected patients, and distal gradients in 24.3%. Fifty-two patients out of the 627 (8.2%) had to be reoperated for residual VSD, RVOT aneurysm, valvular pulmonary stenosis or peripheral stenosis. Intracardial electrophysiological tests carried out in 166 patients postoperatively showed an antegrade effective refractory period of the AV-node lasting over 400 ms in 47 patients (28.3%), as well as additional ventricular action potentials in 117 patients (70.4%), which could be correlated to extrasystoles or ventricular tachycardia in 37.9% of the cases. Additional AV-pathways were disclosed in 3 patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Discrete subaortic stenosis: the value of cross-sectional sector echocardiography in evaluating different types of obstruction.

The value of cross-sectional sector echocardiography in the visualization of discrete subaortic stenosis (DSS) was investigated using an 80 degrees phased-array sector scanner with simultaneously derived M-mode outputs. Thirty-three patients (including 22 postoperative patients) with proven DSS were investigated and divided into two groups: group I--discrete membranous type; and group II--diffuse fibromuscular type. In group I (15 patients), two isolated subaortic ridges were identified as discrete linear echoes in the long axis of the outflow tract in five patients. A single distinct and isolated linear echo was observed in three patients, whereas in another five the ridges appeared to be attached to the ventricular septum and/or to the base of the anterior mitral leaflet. In two patients with mild DSS, a false-negative diagnosis was made. Only 2 out of 12 patients in this group showed a short remnant of the ridge after surgical revision. In group II, a more generalized or long-segment narrowing was present in 18 patients; in 14 of them the ridges were continuous with the walls of the outflow tract. Eight out of ten patients reexamined following resection of fibromuscular tissue still had residual obstruction. Analysis of the simultaneous M-mode recordings revealed that the transient appearance of the ridge in the outflow tract depended on the normal movement of the heart within the chest, on the lengthening of the membrane itself, and on the angle between the ultrasound beam and the membrane during different cardiac cycles. Our study shows that a spectrum of one- and two-dimensional patterns exists depending on the nature of the obstructing lesion. Cross-sectional sector echocardiography provides more direct visualization and characterization of various types of DSS than M-mode echocardiography does.

Qualitative and quantitative evaluation of supravalvar aortic stenosis by cross-sectional echocardiography. A report of 80 patients.

Cross-sectional and concurrent M-mode echocardiograms of the left ventricular outflow tract and the ascending aorta were performed in 80 patients with supravalvar aortic stenosis (SVAS) selected from a total of 178 patients in whom the diagnosis had been established earlier by cardiac catheterization and angiocardiography. Visualization of the area of obstruction was possible in 77 patients using the cross-sectional system. In 34 cases recatheterization and angiocardiography of the left heart were carried out. To quantitate the severity of obstruction we used the pressure difference across the stenosis and the ratio of the cross-sectional areas at the level of the aortic annulus and of maximal supravalve stenosis. These cross-sectional areas were estimated from values for aortic diameter derived from scans in the long axis of the aorta, assuming the cross-sections to be circular. There was a good correlation between the ratios calculated from the echocardiogram and those calculated from the angiocardiogram (r = 0.894, n = 34, 0.747 less than p greater than 0.938). There was also a good correlation between the ratio of the surface areas calculated from the echocardiogram and the corresponding measured pressure differences (r = 0.932, n = .36, 0.878 less than p greater than 0.973). This study shows that cross-sectional echocardiography may be useful for estimating the severity of obstruction in SVAS.

Aortoventriculoplasty for different types of left ventricular outflow tract obstructions.

Since the first clinical application of aortoventriculoplasty for tunnel subaortic stenosis in 1974 the indication for this method was extended to other types of left ventricular outflow tract stenoses (LVOTO). The operative technique consists of enlarging both the left and right ventricular outflow tracts and inserting an aortic prosthetic valve. 47 operations have been performed in patients with various types of LVOTO: 8 narrow annulus, 23 diffuse subaortic stenosis (multiple level stenosis), 9 complex forms of tunnel subaortic stenosis (Shone complex) 3 outgrown prosthesis, 4 obstructive idiopathic hypertrophic subaortic stenosis. Patients ages ranged from 4 to 35 years. Overall mortality was 13%, there were no late deaths, in the last 34 patients there was no death. In 25 patients there had been 1, and in 13 patients 2 previous procedures. As a result of the operation 9 patients developed complete right bundle branch block or left anterior hemi-block; 2 patients developed total a-v block with the need of a permanent pacemaker 25 patients had catheterization postoperatively. The mean gradient across the left ventricular outflow tract was significantly reduced from 91.5 +/- 21 mm Hg to 13.1 +/- 15 mm Hg. According to our experience aortoventriculoplasty can be used routinely in all forms of diffuse subaortic stenosis, narrow aortic annulus, reoperation in HOCM, multiple level stenosis and outgrown aortic prosthesis.

Conduit repair for complex congenital heart disease with pulmonary atresia or right ventricular outflow tract obstruction. part I: surgical results.

From 1972 to 1981, 40 valved extracardiac conduits have been implanted to bridge the right ventricular outflow tract (RVOT) in 37 patients for different complex congenital cardiac anomalies. The patients ranged in age from 2 to 23 years (mean 8.5 years). Two Dacron prostheses with incorporated Lillehei-Kaster valves, 1 valveless Dacron conduit, 27 Hancock conduits, and 9 lonescu-Shiley conduits were chosen according to availability and the progress in conduit technology. Thirty-three patients had had up to 4 previous palliative procedure before conduit repair. Although the complication rate appears considerable, the mortality rate seemed to be unaffected by the high percentage of prior surgery. Exchange of the conduit became necessary in 2 children, because of conduit stenosis with calcification of the Hancock valve 5 and 7 years respectively after implantation, and in another patient an outgrown Lillehei-Kaster valve Dacron conduit had to be replaced 9 years after repair. Five children died in the early postoperative course: one in pulmonary failure and kinking of the conduit; one with right heart failure and pulmonary hypertension stage IV; 2 in myocardial failure, and one due to severe bleeding from myocardial failure, and one due to severe bleeding from the prosthesis. Three patients died in the late postoperative course 11 weeks, 4 years and 4 years respectively after conduit repair. Conduit surgery offers new possibilities for repair of complex cyanotic cardiac malformations. At present, however, none of the commercially available conduits is an ideal substitute. Our limited experience with the hemodynamic results of lonescu Shiley conduits is promising although longer observation periods are needed for a definitive judgement. At present, the largest possible conduit should be used whenever possible; problems of compression or kinking can be avoided with proper positioning of the conduit.

Conduit repair for complex congenital heart disease with pulmonary atresia or right ventricular outflow tract obstruction. Part II: early and late hemodynamic and echocardiographic findings.

The results are presented of 44 systematic cardiac catheterizations in 35 patients after successful repair of various types of congenital cyanotic heart disease using a conduit. The operations were performed from 1972 to 1981. The patients were followed from 6 months to 9 years, the mean interval between operation and catheterization was 2.5 years (4 weeks to 8 years). Different types of conduits were used: a Hancock conduit in 27 cases (1 replaced), an aortic homograft in 3 cases (all 3 replaced by a Hancock conduit), a Dacron tube with Lillehei-Kaster valve in 2 cases (1 replaced), a lonescu-Shiley conduit in 5 cases, a composite graft of pericardium and a Hancock valve in one patient (replaced) and a valveless Dacron tube in one patient. The total conduit gradient was differentiated in 43/44 investigations. For the Hancock conduit the mean proximal gradient was 9 mmHg, the valvular 14 and the distal 13 mmHg. Severe valvular stenosis of the porcine valve occurred in 3 patients. For the lonescu-Shiley conduit only early, but promising, results are available. Three of the 35 patients died late (2.5 and 4 years postoperatively); the deaths were related to severe additional lesions. Cross-sectional echocardiography was performed in 32 of the 35 patients. The latter does not appear to be a reliable method for the detection of valvular lesions so far, but is helpful for the diagnosis of proximal and distal obstructions of the conduit.

Fontan procedure--indication and clinical results.

Twenty-six patients with tricuspid atresia (15), univentricular heart (7), and single ventricle (4) underwent 27 Fontan or modified Fontan procedures between 1975 and 1981. The age of the patients varied between 4 and 26 years. Twenty patients had had a total of 33 palliative operations prior to correction. The original Fontan procedure was performed in 10 patients from 1975 to 1977. According to the various anatomical findings modifications of the Fontan procedure, such as direct anastomosis or implantation of a valveless conduit, were introduced in 1977. Early mortality among all the patients was 22% (6 patients died). Three deaths occurred in the initial period 1975 to 1977. Among the last 20 patients (1978 to 1981) there were 3 early deaths. Three patients with single ventricle survived, one died due to pulmonary failure. There were 2 late deaths (sepsis, sudden cardiac death). Postoperative cardiac catheterization performed in 17 patients revealed excellent results in 13 patients; the remaining 4 displayed diminished arterial oxygen saturation, three of them had Glenn palliation prior to corrective surgery. Postoperative right atrial mean pressure varied from 10 to 23 mmHg. The left ventricular parameters were within the normal range.

Hemodynamic findings before and after aortoventriculoplasty (AVP).

Between June 1974 and July 1981, aortoventriculoplasty (AVP) has been applied in 57 patients with several types of left ventricular outflow tract obstruction ranging in age from 5 to 34 years. There were 7 early deaths (mortality 12%); 5 of these occurred in the first 10 patients operated upon. Eighteen patients developed complete right bundle branch block or left anterior hemiblock or both; in another patient a transient complete left bundle branch block occurred postoperatively. Two patients had a permanent AV-block. In contrast to the unsatisfactory hemodynamic results of previous conventional operations, AVP reduced the mean residual resting gradient across the left ventricular outflow tract from 85 +/- 17 mmHg (range 60 to 140 mmHg) to 12 +/- 12 mmHg (range 0 to 65 mmHg). Except in 2 patients, this gradient did not increase by more than 15 mmHg under Isoproterenol (range 0 to 35 mmHg). In 25% of the restudied patients the left ventricular enddiastolic pressure returned to normal after AVP. In 3 patients a small ventricular septal defect in the area of the patched septal incision was detected by oximetry and angiocardiography, whereas mild aortic regurgitation was present in another 6 patients. Residual gradients across the right ventricular outflow tract in 5 patients ranged from 17 to 40 mmHg. This study shows the hemodynamic results obtained by AVP to be superior to those of conventional surgery. The major advantage of AVP as compared to total homograft replacement of the aortic root and to the apico-aortic conduit operation, is its applicability in all types of left ventricular outflow tract obstruction.

Surgical treatment of various types of left ventricular outflow tract stenosis by aortoventriculoplasty--clinical results.

Since 1974 the new concept of aortoventriculoplasty (AVP) has been applied clinically in Göttingen. Out of 1,112 patients with various types of congenital aortic stenosis 502 patients have undergone commissurotomy, resection of a subvalvular ring, myotomy and supravalvular patch plasty. Fifty-seven patients were treated by AVP, in only 11 patients was AVP the first procedure, 46 had had one or more previous operations. Total hospital mortality was 12.2%; in the last 37 cases there was only one death. Two patients suffered permanent AV block. The mean left ventricular-aorta gradient was reduced from 94 +/- 24 mmHg to 14 +/- 15 mmHg after AVP. In our clinical material the indications for AVP (n = 57) have been the following: valvular aortic stenosis with narrow annulus (8 patients), diffuse subaortic stenosis (20) (from collar-like to tunnel-like, out of these patients 6 with Shone-complex), multi-level stenosis (20), outgrown prosthesis (4), hypertrophic obstructive cardiomyopathy (5). In comparison to the apico-aortic conduit procedure and total replacement of the aortic root by homograft, the clinical results indicate AVP to be a simple and easy-to-apply operative technique.

[Hypertensive pulmonary vascular disease in complete transposition of the great arteries (author's transl)]. / Widerstandsbedingte Pulmonalhypertonie bei kompletter Transposition der grossen Arterien.

Pulmonary vascular disease and heart failure are the two major problems in complete transposition of the great arteries (TGA) with increased pulmonary flow. Hypertensive pulmonary vascular disease was observed in patients with complete TGA and increased flow (3.6%) as well as in those without increased pulmonary flow (3.3%). An intact ventricular septum or pulmonic stenosis did not appear to prevent the occurrence of progressive pulmonary vascular disease in all patients. The pulmonary lesion observed in these subjects cannot be explained by chronic severe volume overload alone. Clinically unrecognized pulmonary microthrombi are an additional cause for the development of pulmonary vascular disease in patients with complete TGA. Therefore cyanosis and its complications can be a major factor beside increased pulmonary flow in causing pulmonary vascular changes. Early corrective surgery performed after the age of 3 months is the therapy of choice to avoid progressive pulmonary vascular damage and other thrombo-embolic accidents.

[New aspects in the pathogenesis of the prolonged QT-interval syndrome with syncopal attacks. Intracardiac ECG recordings during atrial stimulation in 4 patients (author's transl)]. / Neue Erkenntnisse in der Pathogenese de verlängerten QT-Syndroms mit synkopalen Anfällen. Intrakardiale Ekg-Ableitungen während programmierter Vorhofstimulation bei 4 Patienten.

Three families with the syndrome of hereditary prolonged QT interval affecting 12 members in two or three generations are described. Four patients with sinus bradycardia and frequent syncopal attacks were investigated by Holter-monitoring, His-bundle electrograms and exercise testing. Corrected QT intervals (QTc) were prolonged from 0.43 to 0.54 seconds at rest. In His-bundle electrograms, during atrial pacing at increasing rates the function of the entire conduction system seemed to be affected. Three patients were treated with pindolol and one patient with a permanent demand pacemaker and pindolol. During progressive exercise testing performed after drug therapy or pacemaker treatment, heart rate increased unsatisfactorily and QTc-intervals lengthened whereas atrial stimulation QTc-intervals remained unchanged. In the patient with a permanent demand pacemaker, electrocardiographic monitoring revealed a period of 25 seconds of ventricular tachycardia occurring at rest and ceasing spontaneously. In the past 1.2 years to 2.5 years (mean 2.1 years) of outpatient follow-up, the patients had normal exercise tolerance and syncopal attacks did not occur on pindolol 30 mg/day. Our findings suggest rather a hypersensitivity of the affected conclusion system in the presence of a normal activity of cardiac sympathetic nerves.

[The "steal" syndrome and the development of pulmonary arterio-venous shunt after Glenn and/or Fontan operations (author's transl)]. / Das "Steal"-Syndrom und die Entstehung arteriovenöser pulmonaler Shunts nach Glenn und/oder Fontan-Operationen.

18 patients with superior vena cava-right pulmonary artery (Glenn) anastomosis and 7 patients with right atrium-pulmonary artery (Fontan) conduit operation were investigated by selective angiography, oximetry and contrast echocardiography. 11 patients with Glenn anastomosis (61.1%) developed a "steal" syndrome in 4 11/12 to 9 7/12 years postoperatively. In 2 patients pulmonary arteriovenous shunt could be documented by selective angiocardiogram, oximetry and contrast echocardiography, and in 1 patient by contrast echocardiography only (16.6%). None of the patients with Fontan operation developed detectable pulmonary arteriovenous shunt in the follow-up period. The effect of the changed haemodynamics after Fontan operation on the "steal" syndrome in patients with prior performed Glen anastomosis is that to diminish or abolish collateral flow. There is no influence on the abnormal intrapulmonary arteriovenous communications.

[Reconstruction of underdeveloped right ventricle and tricuspid hypoplasia (author's transl)]. / Rekonstruktion des unterentwickelten rechten Ventrikelsmit Trikuspidalhypoplasie.

Total correction of underdeveloped right ventricle related to tricuspid hypoplasia has been performed in 6 patients at the department of thoracic and cardiovascular surgery University Göttingen. In 5 patients reconstruction of a four-chamber-four-valved heart could be accomplished. 1 patient with a poor result after Fontan's operation, performed one year previously, showed a significant growth in size of the hypoplastic right ventricle in the postoperative angiogram, but died 14 hours after reoperation. Prior to corrective surgery, 4 patients required 1 or 2 palliative procedures: 3 Glenn- and 2 Blalock-Taussig operations and a pulmonary valvulotomy in 1 patient. A Hancock-valved conduit was inserted between the right atrium and the hypoplastic right ventricle as an inlet of this chamber after closure of the ASD and VSD in 4 patients. The conduits are bypassing the hypoplastic tricuspid valve orifices closed during corrective surgery. In the remainder 2 patients with moderate tricuspid and right ventricle hypoplasia, closure of the ASD was performed only. Anomalous muscle bundles and fibrous tissue inside the right ventricular cavity were resected surgically, safely. 4 to 12 months after corrective surgery the 5 survivors were investigated by cardiac catheterization. In the 3 patients operated with a valved conduit there was a moderate growth in size of the hypoplastic right ventricle, the right atrial pressure was elevated and ranged from p = 14 to 16 mm Hg. There was a slight right atrial-right ventricular gradient of 4 mm Hg across the valved conduit. The 2 patients with closure of the ASD and VSD only had a nearly normal-sized right ventricle and a right atrial pressure of p = 10 mm Hg or less at the postoperative right ventricle and a right atrial pressure of p = 10 mm Hg or less at the postoperative investigation. All of them were acyanotic and had an improved or normal exercise tolerance. We concluded that reconstruction of an underdeveloped right ventricle in well-selected cases will yield more physiological benefits than do current surgical procedures, in which a conduit is interposed between the right atrium and the main pulmonary artery.

[Late results after Rastelli correction in transposition of the great arteries (author's transl)]. / Spätergebnisse nach Korrekturoperationen bei Transposition der grossen Gefässe nach Rastelli.

From 1974 to 1978, 11 patients underwent a Rastelli correction in transposition of the great arteries with VSD and obstruction to the pulmonary artery. 2 patients died, a mortality of 18%. All patients received a Hancock-conduit. On the average of 30 months after the operation, a complete heart catheterisation was performed. In 6 patients--55%--there was no or only a mild gradient between the RV and AP (Gradient under 40 mm Hg). 3 patients (27%) developed a considerable obstruction to the pulmonary artery (gradient over 70 mm Hg) proximal, valvular, or distal. Subaortic obstruction was not observed. 3 of the 9 patients had a residual VSD, detectable by oxymetry, 1 with a flow ratio of 1.8, which required surgery (successfully closed).

Fontan procedure and surgical modification in tricuspid atresia.

Nineteen patients with tricuspid atresia and reduced lung perfusion (valvular-and/or subvalvular pulmonary stenosis, transposition of the great arteries and/or single atrium) were operated in the period 1975--1979. The surgical procedures employed varied according to the additional cardiac defects. The age of the patients was between 2 and 18 years. Eleven children received a contuit with a Hancock valve, 8 children a valveless conduit. In 9 patients it was possible to connect the conduit to the right ventricle using the pumping action of the right ventricle with an anatomically intact pulmonary valve. Six patients died (4 early deaths, 2 late deaths, early mortality rate 21%). In this study, the postoperative courses, which were complicated in several cases, are related to the hemodynamical findings. Thirteen children were examined between 1 and 38 months following the operation. Cardiac catheterization was performed in 10 patients. Of the 13, 10 had fully saturated arterial blood. A remnant atrial defect was demonstrated in one child, and 2 displayed intrapulmonary shunts attendant to Glenn anastomoses which had been in place for 10 to 12 years. Among the patients the right atrial pressure ranged from 10 to 20 mmHg with a mean value of 14.5 +/- 0.9 mmHg. An increase in size of the right ventricle was demonstrated angiographically in the case of 2 patients who had valve-bearing conduits to the right ventricle.

Aortoventriculoplasty for tunnel subaortic stenosis and other obstructions of the left ventricular outflow tract. Clinical and hemodynamic results.

A new therapeutic concept of enlarging the outflow tracts of both ventricles with a patch and inserting an aortic prosthesis has been developed for the treatment of tunnel subaortic stenosis. This operation has been applied clinically since June 1974 on several types of obstruction in the outflow tract of the left ventricle. Twenty-one operations have been performed on 20 patients under the age of 18 years, with an overall mortality of 24% and no late deaths. Seven patients developed complete right bundle branch block or left anterior hemiblock or both as a result of this operation; transient atrioventricular block and complete left bundle branch block occurred in one patient each. In no case, however, did rhythm disturbances contribute to death. In one patient, the septal incision injured a septal coronary artery, with fatal result. Fourteen patients had catheterization studies postoperatively. Although previous conventional surgery had been unsuccessful, aortoventriculoplasty (AoVPI) reduced the mean gradient across the left ventricular outflow tract significantly (p less than or equal to 0.01), from 94.7 +/- 25.5 mm Hg to 14.4 +/- 17.2 mm Hg, leaving the end-diastolic pressure practically unchanged. No significant defect remained in the patch-covered septal incision. Thus, we consider AoVPI to be the operation of choice for tunnel subaortic stenosis, for valvular aortic stenosis with a narrow annulus and in cases where an artificial aortic valve has become too small because of the patient's growth.