Biomedical subjects

G K Danielson

Publications and source records attributed to G K Danielson.

At least 37 records · Page 2Linked to original sources

PubMed1999

Fixed left ventricular outflow tract obstruction in presumed hypertrophic obstructive cardiomyopathy: implications for therapy.

BACKGROUND: A subset of patients presenting with a presumed diagnosis of hypertrophic obstructive cardiomyopathy (HOCM) have a fixed left ventricular outflow tract (LVOT) obstruction. Recognition of this pathophysiologic abnormality is important in choosing therapy. METHODS: Of patients referred for treatment of HOCM, 4 had fixed LVOT obstruction. Clinical and echocardiographic data and surgical findings were reviewed. RESULTS: In the 4 patients with clinical features consistent with HOCM or HOCM-like conditions, echocardiography showed fixed LVOT obstruction with an early-peaking LVOT Doppler signal or absence of severe systolic anterior motion of the mitral valve. The causes of fixed obstruction included accessory mitral tissue with associated fibrous ring (1 patient), fixed subaortic tunnel stenosis (2 patients), and a discreet subaortic ridge (1 patient). After surgical relief of the fixed LVOT obstruction, all patients had relief of the ventricular outflow tract gradient. CONCLUSIONS: Not all patients with a presumed diagnosis of HOCM have isolated dynamic LVOT obstruction but may have isolated or additional fixed obstruction. Careful two-dimensional and Doppler echocardiography are needed to identify this subset of patients who are best treated surgically.

Adult↗

PubMed1999

Coronary artery bypass grafting in patients with previous mediastinal radiation therapy.

OBJECTIVES: Our objectives were to characterize the outcome of coronary artery bypass grafting in patients with previous mediastinal radiation therapy and to identify special features of this condition that relate to surgical management. PATIENTS AND METHODS: We conducted a retrospective review of 47 patients (28 women, 19 men) with a mean age of 63.5 +/- 12.8 years (range 31.0-82. 9 years) from 1976 through December 1996 undergoing coronary artery bypass graft after mediastinal radiation therapy. RESULTS: The mean interval between mediastinal radiation therapy and coronary artery bypass grafting was 15.1 +/- 9.8 years (range 1.1-37.8 years). In the 44 patients with isolated coronary surgery, operative mortality was 3 patients (6.8%). Sternal wound infection occurred in 3 patients (6.8%). Actuarial survival at 1 and 5 years was 87.2% +/- 4. 9% and 71.6% +/- 7.1%, respectively. Total follow-up was 293.7 patient-years (mean 6.2 +/- 5.1 years). There were 17 late deaths (malignancy, n = 7; heart failure, n = 6; stroke, n = 1; other noncardiac causes, n = 2; and sudden death, n = 1). Twelve of 43 discharged patients had the development of valvular disease demonstrated by follow-up echocardiography. CONCLUSIONS: The early results of coronary artery bypass grafting for the treatment of ischemic heart disease after mediastinal radiation therapy are good. Late survival, however, is limited by malignancy, either recurrent or new, and the development of heart failure. Inasmuch as 25 other patients after radiation therapy required concomitant valve surgery and 12 of 43 (28%) discharged patients had later development of valvular disease, with 2 requiring reoperation, careful assessment of any valvular lesion is important during the initial coronary artery bypass grafting. Careful follow-up, including regular echocardiographic screening, is recommended in this patient population.

Adult↗

PubMed1999

Left ventricular systolic and diastolic function after pericardiectomy in patients with constrictive pericarditis: Doppler echocardiographic findings and correlation with clinical status.

OBJECTIVES: The study assessed changes in left ventricular systolic and diastolic function after pericardiectomy in patients with constrictive pericarditis and correlated postoperative Doppler echocardiographic findings with clinical status. BACKGROUND: Despite the efficacy of pericardiectomy, some patients with constrictive pericarditis fail to improve postoperatively. Data on serial evaluation of systolic and diastolic function after pericardiectomy and its relation to clinical status are not available. METHODS: From 1985 to 1995, a total of 58 patients with constrictive pericarditis underwent pericardiectomy and had at least one follow-up Doppler echocardiographic study with a respirometer: 23 patients had one examination within 3 months postoperatively, 19 had a study within 3 months and another one more than 3 months postoperatively, and 16 had one study more than 3 months postoperatively. RESULTS: In the early postoperative period, diastolic function was normal in 17 patients (40.5%), restrictive in 17 (40.5%), and constrictive in 8 (19%). Among 19 patients who had serial Doppler echocardiography, in 2 patients with restrictive physiology and 5 with constrictive physiology the results had become normal, and 1 patient who had had constrictive physiology had restrictive findings. In late follow-up, left ventricular end-diastolic diameter increased compared with preoperative measurement (p = 0.0009). Diastolic filling pattern at late follow-up was normal in 20 patients (57%), restrictive in 12 (34%) and constrictive in 3 (9%). There was a significant relationship between diastolic filling patterns and symptomatic status (chi2 = 20.9, p < 0.0001). Patients with persistent abnormal diastolic filling on Doppler echocardiography had had symptoms for a longer time preoperatively than did patients with normal diastolic physiology (p = 0.0471). CONCLUSIONS: Diastolic filling characteristics remain abnormal in a substantial number of patients with constrictive pericarditis after pericardiectomy. These abnormalities may resolve gradually but can persist. Diastolic filling abnormalities after pericardiectomy correlate well with clinical symptoms and tend to occur in patients who have had symptoms longer preoperatively. This finding supports the recommendation that pericardiectomy be performed promptly in symptomatic patients with constrictive pericarditis.

Adolescent↗

PubMed1999

Comparison of dual-chamber pacing versus septal myectomy for the treatment of patients with hypertrophic obstructive cardiomyopathy: a comparison of objective hemodynamic and exercise end points.

OBJECTIVES: The purpose of this study was to compare the treatment effects of septal myectomy with dual-chamber pacing in patients with hypertrophic obstructive cardiomyopathy (HOCM). BACKGROUND: The optimal treatment for symptomatic patients with drug-refractory HOCM is unknown. Both dual-chamber pacing and surgical myectomy may result in subjective symptom improvement. However, no direct comparisons with objective end points have been reported. METHODS: Thirty-nine patients with symptomatic HOCM were analyzed in this concurrent cohort study. Twenty patients underwent surgical myectomy, and 19 received dual-chamber pacemakers based on patient preference. These patients had prospective baseline and follow-up evaluations including physician assessment, echocardiography and standardized metabolic treadmill exercise testing. RESULTS: Baseline symptom status, left ventricular outflow tract gradients, exercise times and maximal oxygen consumption peak were similar between the two groups. Left ventricular outflow gradient was reduced from 76+/-57 to 9+/-17 mm Hg (p = 0.0001) after myectomy, and from 77+/-61 to 55+/-39 mm Hg (p = 0.07) after pacing (p = 0.02 for comparison with myectomy). Ninety percent of myectomy patients experienced symptomatic improvement as compared with 47% in the pacing group. Exercise duration increased significantly from 6.6+/-2.8 to 8.7+/-3.0 min (p = 0.0003) after myectomy compared with a change from 6.4+/-2.1 to 7.0+/-2.2 min (p = NS) in the pacing group. Maximal oxygen consumption increased from 19.4+/-6.4 to 22.2+/-6.5 ml/kg/min after myectomy (p = 0.004), whereas the pacing group did not experience any significant change (19.6+/-6.5 vs. 20.1+/-6.5 ml/kg/min, p = NS). CONCLUSIONS: Surgical myectomy and dual-chamber pacing improve subjective measures of functional status in patients with symptomatic HOCM. In this nonrandomized study, myectomy offered greater reduction in left ventricular outflow tract gradients and larger improvements in objective measures of patient symptoms and functional status when compared with dual-chamber pacing.

Aged↗

PubMed1999

Permanent pacing in patients with univentricular heart.

Patients with one of several varieties of malformation designated as "univentricular hearts" may be especially challenging when permanent pacing is required. Our objective was to review our experience in this subset of patients that had undergone permanent pacing and thus determine the optimal approach. A retrospective chart review was done of 32 patients with some variety of "univentricular" malformation who had required permanent pacing at our institution. Although technically challenging, permanent pacing in this group of patients can be successful through several approaches. The various approaches, as well as consideration of the differences that exist between patients undergoing septation and those undergoing a Fontan procedure are discussed. Although long-term permanent pacing is possible in this group of patients, before pacing begins, a thorough understanding of the anatomy and prior surgical procedures is necessary. Use of a combined atrial transvenous and ventricular epicardial pacing system may work well for some patients. With the development of newer and more reliable coronary sinus leads, dual chamber transvenous pacing with ventricular stimulation via the coronary sinus could become the approach of choice in some patients with "univentricular hearts."

Adolescent↗

PubMed1998

Pitfalls in clinical recognition and a novel operative approach for hypertrophic cardiomyopathy with severe outflow obstruction due to anomalous papillary muscle.

BACKGROUND: Ventricular septal myotomy/myectomy (Morrow procedure) is the standard surgical option for severely symptomatic patients with hypertrophic cardiomyopathy (HCM) and marked basal obstruction to left ventricular outflow due to mitral valve systolic anterior motion. In some patients, however, congenital malformations of the mitral apparatus may be responsible for outflow obstruction; the failure to recognize this morphology before operation could have adverse consequences. METHODS AND RESULTS: We recently evaluated 2 patients with obstructive HCM operated on at Mayo Medical Center in 1997 who demonstrated direct anomalous papillary muscle insertion into the anterior mitral leaflet, producing muscular midcavity obstruction. This anomaly is potentially identifiable with echocardiography by exaggerated anterior displacement of hypertrophied papillary muscles within the left ventricular cavity and the direct continuity between papillary muscle and anterior leaflet associated with a rigid motion pattern of the mitral apparatus. Echocardiographic diagnosis, however, was confused in both patients by the association of systolic anterior motion of the mitral valve, probably produced by freely mobile margins of the mitral leaflet unencumbered by papillary muscle insertion, and in 1 patient probably representing a second and more basal level of obstruction. Because outflow tract morphology was judged unsuitable for conventional myotomy/myectomy, a novel surgical strategy was designed to remove the outflow gradient in which an extensive myectomy trough (wider at its apical than basal extent) was created within the ventricular septum to papillary muscle level; also, in 1 patient, attachment of anterolateral papillary muscle with the lateral free wall was partially severed to increase mobility of the mitral apparatus. After surgery, both patients reported substantial relief of symptoms and improved exercise tolerance and also showed reduced or abolished basal outflow obstruction. CONCLUSIONS: In HCM, outflow obstruction due to anomalous papillary muscle insertion directly into anterior mitral leaflet is challenging to identify but should always be contemplated before operative intervention. This important (but often unsuspected) congenital malformation may require alternative surgical strategies to standard myotomy/myectomy, similar to those described here.

Adolescent↗

PubMed1998

Predictors of early- and late-onset supraventricular tachyarrhythmias after Fontan operation.

BACKGROUND: The objectives of our study were to determine the frequency of supraventricular tachyarrhythmias (SVTAs) among modifications of the Fontan operation and identify risk factors for developing SVTA. METHODS AND RESULTS: The population consisted of all patients who had any modification of the Fontan operation at the Mayo Clinic between 1985 and 1993. Clinically significant SVTAs were those requiring initiation or change of antiarrhythmic treatment, and they were divided into early SVTAs (<30 days after the operation) and late SVTAs (>/=30 days after the operation). Clinical histories were reviewed, and health status questionnaires were sent. Four hundred ninety-nine patients had various modifications of the Fontan operation. Frequency of early SVTA was 15%. Risk factors identified by multivariate analysis for early SVTA were AV valve regurgitation, abnormal AV valve, and preoperative SVTA. Frequency of late SVTA was 6% by 1 year, 12% by 3 years, and 17% by 5 years. Risk factors for late SVTA were age at operation (<3 or >/=10 years) and systemic AV valve replacement. By univariate and multivariate analysis, the type of Fontan operation was not a significant risk factor for late SVTA when all 6 modifications were considered. However, when we analyzed the frequency of late SVTA for the 2 recently used modifications, we found a lower frequency of late SVTA in patients with atriopulmonary connection with lateral tunnel compared with those with total cavopulmonary connection. CONCLUSIONS: Postoperative SVTA continues to be a significant problem. Risk factors for SVTA are AV valve regurgitation, abnormal AV valve, preoperative SVTA, and age at operation. Frequency of SVTA does not appear to be related to type of Fontan procedure except for slightly lower frequency in patients with atriopulmonary connection with lateral tunnel compared with those with total cavopulmonary connection.

Adolescent↗

PubMed1998

Right-sided maze procedure for right atrial arrhythmias in congenital heart disease.

BACKGROUND: Atrial fibrillation and flutter, commonly associated with congenital heart anomalies that cause right atrial dilatation, may cause significant morbidity and reduction of quality of life, even after surgical repair of the anomalies. METHODS: In an effort to reduce the incidence of atrial tachyarrhythmias after repair of right-sided congenital heart disease, we performed a concomitant right-sided maze procedure. RESULTS: Eighteen patients with paroxysmal atrial fibrillation or flutter (n = 12) or chronic atrial fibrillation or flutter (n = 6) aged 10.9 to 68.4 years (mean 34.9 years) underwent a right-sided maze in association with repair of Ebstein's anomaly (n = 15), congenital tricuspid insufficiency (n = 2), and isolated atrial septal defect (n = 1). There were no early deaths, reoperations, or complete heart block. Discharge rhythm was sinus (n = 16) or junctional (n = 2). Follow-up was complete in all 18 patients and ranged from 3.1 to 17.2 months (mean 8.1 months); all are in New York Heart Association class I. Early postoperative arrhythmias developed in 3 patients (all were converted to sinus rhythm by antiarrhythmic drugs). There were no late deaths or reoperations. CONCLUSIONS: The inclusion of a right-sided maze procedure with cardiac repair in patients having congenital heart anomalies that cause right atrial dilatation and associated atrial tachyarrhythmias is effective in eliminating or reducing the incidence of those arrhythmias.

Adolescent↗

PubMed1998

Late results of bioprosthetic tricuspid valve replacement in Ebstein's anomaly.

BACKGROUND: Historically, porcine bioprosthetic valves have poor durability in pediatric patients; nearly half will require replacement within 5 years. However, our early experience with patients having Ebstein's anomaly suggests that tricuspid bioprostheses in this anomaly might have better durability. METHODS: One hundred fifty-eight patients who received a primary tricuspid bioprosthesis because of tricuspid valve anatomy unsuitable for repair between April 1972 and January 1997 were reviewed. Results were analyzed and Kaplan-Meier curves were constructed to estimate patient survival and probability of remaining free of reoperation. RESULTS: Follow-up of 149 patients (94.3%) who survived 30 days ranged up to 17.8 years (mean, 4.5 years). Ten-year survival was 92.5%+/-2.5% (SE), 129 late survivors (92.1%) were in New York Heart Association class I or II, and 93.6% were free of anticoagulation. Freedom from bioprosthesis replacement was 97.5%+/-1.9% at 5 years and 80.6%+/-7.6% at 10 and 15 years. CONCLUSIONS: Bioprosthesis durability in the tricuspid position in patients with Ebstein's anomaly compares very favorably with bioprosthesis durability in other cardiac valve positions, especially for pediatric patients, and also compares favorably with tricuspid bioprosthesis durability in patients with other diagnoses.

Adolescent↗

PubMed1998

Cardiac transplantation for end-stage congenital heart defects: the Mayo Clinic experience. Mayo Cardiothoracic Transplant Team.

OBJECTIVE: To review the outcome of cardiac transplantation undertaken in patients with congenital heart defects. MATERIAL AND METHODS: Between November 1991 and March 1998 at our institution, cardiac transplantation was performed in 16 patients with congenital heart disease (age range, 3 to 57 years; mean, 26.1). Preoperative diagnoses included univentricular heart (N = 4); complete transposition of the great arteries (N = 3); Ebstein's anomaly (N = 2); tetralogy of Fallot (N = 2); levotransposition (N = 2); dextrocardia, corrected transposition, ventricular and atrial septal defects, and pulmonary stenosis (N = 1); double-outlet right ventricle (N = 1); and hypertrophic obstructive cardiomyopathy (N = 1). All patients had undergone from one to five previous palliative operations. RESULTS: Four patients required permanent pacemaker implantation during the first month postoperatively because of bradycardia; more than 2 years later, another patient required a permanent pacemaker because of sick sinus syndrome. In addition, one patient had an automatic implantable cardioverter-defibrillator. Three patients required reconstruction of cardiovascular structures with use of prosthetic material (Teflon patches or donor tissue) at the time of cardiac transplantation. Actuarial 1-, 2-, and 5-year survival was 86.2 +/- 9.1%. During the first year after transplantation, two deaths occurred--one at 41 days of putative vascular rejection and the second at 60 days of severe cellular rejection. All other patients are alive and functionally rehabilitated; the mean follow-up period has been 26.1 months (range, 2 to 89.6). CONCLUSION: Cardiac transplantation for patients with congenital heart disease can be accomplished with a low perioperative mortality and an excellent medium-term survival despite the challenges presented by the technical difficulties during invasive diagnostic procedures and at operation and the need for adherence to long-term multiple-drug therapy in this patient population.

Actuarial Analysis↗

PubMed1998

Use of heparin in the treatment of protein-losing enteropathy after fontan operation for complex congenital heart disease.

Protein-losing enteropathy (PLE) is a serious complication of the Fontan operation and is associated with pronounced mortality. Medical management of PLE has been only partially successful. A recent report noted dramatic improvement in patients with PLE within 3 weeks of subcutaneous administration of heparin. We report a case of reversal of PLE with resolution of clinical symptoms and normalization of serum albumin, total protein, and fecal alpha1-antitrypsin values after several months of heparin treatment. Our findings substantiate those recently reported but suggest that reversal of PLE may necessitate more than a few weeks of heparin therapy.

Administration, Cutaneous↗

PubMed1997

Cardiorespiratory response to exercise after modified Fontan operation: determinants of performance.

OBJECTIVES: This study sought to measure the cardiorespiratory responses to exercise and to identify the perioperative determinants of exercise performance in children, adolescents and young adults who underwent the modified Fontan operation. BACKGROUND: Several studies of the cardiorespiratory responses to exercise after the Fontan operation have demonstrated subnormal maximal oxygen uptake and exercise heart rate, but the perioperative variables that ultimately affect exercise responses have not been assessed systematically. METHODS: The study included 59 of the 548 patients who underwent a modified Fontan operation between January 1, 1984 and December 31, 1993 at the Mayo Clinic. Spirometry was performed at rest in all patients before exercise testing. The patients then exercised using a previously calibrated cycle ergometer and a 3-min incremental cycle exercise protocol. Multiple linear regression analysis was used to determine a subset of variables associated with oxygen uptake at peak exercise (VO2max), blood oxygen saturation (O2sat) and heart rate at peak exercise (HRmax). RESULTS: VO2max ranged from 29% to 95% of normal value; O2sat at peak exercise ranged from 77% to 96%; and HRmax ranged from 39.7% to 97.4% of normal value. Multivariate analysis showed that log VO2max/kg2/3 was associated with age at exercise, male gender, body surface area, preoperative confluent pulmonary arteries and rest VO2max/kg2/3. Preoperative left pulmonary artery stenosis, the presence of a classic Glenn anastomosis at exercise and rest O2sat were associated with O2sat at peak exercise. Age, body surface area at exercise, heart rate at rest and diastolic blood pressure were associated with HRmax at exercise. CONCLUSIONS: Subnormal VO2max and HRmax values were demonstrated at peak exercise. Several perioperative variables were associated with VO2max and O2sat at peak exercise. The presence of a classic Glenn anastomosis was associated with decreased O2sat at peak exercise, suggesting intrapulmonary shunting with the classic Glenn anastomosis.

Adolescent↗

PubMed1997

Mimics of Ebstein's anomaly.

The purpose of this study was to determine the most discriminating clinical and echocardiographic features that are most helpful in correctly identifying Ebstein's anomaly of the tricuspid valve from other causes of tricuspid regurgitation. Ebstein's anomaly is an uncommon malformation of the tricuspid valve with diagnostic echocardiographic features. Other cardiac disorders associated with tricuspid valve regurgitation and predominate right-sided heart chamber enlargement can be misdiagnosed as Ebstein's anomaly. All patients who were referred to our institution between 1982 and 1995 with the diagnosis of Ebstein's anomaly but were found to have other abnormalities of the tricuspid value or right ventricle were identified. Their clinical, echocardiographic, and surgical records were reviewed retrospectively. Twenty-two patients (12 males and 10 females), aged 7 to 68 years (mean 33 years), were referred to our institution with the diagnosis of Ebstein's anomaly but were found to have another abnormality that mimicked clinical and diagnostic features of Ebstein's anomaly. The most common initial symptom was exercise intolerance (13 [59%] patients) followed by atrial arrhythmia (seven [32%] patients). Two patients had cyanosis. Three patients had paroxysmal and six had chronic atrial fibrillation/flutter. Cardiomegaly on chest x-ray film was noted in 18 (82%) patients. Referral diagnosis of Ebstein's anomaly had been made by echocardiography (12 patients), cardiac catheterization (four patients), both techniques (five patients), and echocardiography and magnetic resonance imaging (one patient). All 22 patients had predominate right atrial and right ventricular enlargement, and 18 (82%) of 22 patients also had right ventricular dysfunction. However, Ebstein's anomaly was confidently ruled out with repeat comprehensive echocardiography at our institution by establishing (1) absence of significant apical displacement of the septal tricuspid valve leaflet (> or = 8 mm/m2) and (2) lack of a redundant, elongated, anterior tricuspid valve leaflet in all 22 patients (100%). All had significant tricuspid regurgitation caused by tricuspid valve dysplasia (nine patients), tricuspid valve prolapse (four patients), trauma (four patients), right ventricular dysplasia (three patients), endocarditis (one patient), and annular dilation caused by free pulmonary regurgitation (one patient). In all 15 patients who subsequently underwent surgery (tricuspid valve repair [seven patients] or replacement [eight patients]), the absence of Ebstein's anomaly was confirmed. Echocardiographic absence of the characteristic degree of displacement of the septal leaflet of the tricuspid valve (> or = 8 mm/m2) and the presence of a nonelongated, nonredundant anterior tricuspid valve leaflet consistently excluded the diagnosis of Ebstein's anomaly. Under such circumstances, other anomalies of the tricuspid valve or right ventricle were consistently identified. Recognition of the mimics of Ebstein's anomaly had important surgical implications.

Adolescent↗

PubMed1997

Event status of the Starr-Edwards aortic valve to 20 years: a benchmark for comparison.

BACKGROUND: Considerable effort and expense has been invested in the evolutionary development of cardiac valvular prostheses with the goal of reducing or minimizing specific events related to these prostheses. It is important to measure any improvement achieved with such development by comparison against a historic standard. The Starr-Edwards caged-ball prosthesis model 1260 has been used for 30 years as the predominant or sole model of its kind for aortic valve replacement. This historic opportunity provides a benchmark for subsequent improvement and comparison of current prostheses. METHODS: Between 1969 and 1991, 1,100 patients (median age, 57 years; 838 men and 194 women) underwent aortic valve replacement with or without coronary artery bypass grafting (aortic valve replacement, 964; aortic valve replacement plus coronary artery bypass grafting, 136) with the 1260 Starr-Edwards caged-ball prosthesis. RESULTS: Operative mortality was 6.2% (68 patients). Univariate patient characteristics predictive of early mortality were female sex (p = 0.003), age (> 56 years; p = 0.002), recent operative interval (1985 to 1991 versus 1969 to 1976 or 1977 to 1984; p = 0.002), presence of atrial fibrillation (p = 0.001), and small valve size (7A to 8A = 19 to 21 mm; p < 0.001). Follow-up extended to 11,293 patient-years (mean, 24.8 years) and was 96.9% complete. Survival at 5, 10, 15, and 20 years for all patients including operative mortality was 76.6%, 59.6%, 44.9%, and 31.2%, respectively. Operative variables predictive of poor late survival were advanced New York Heart Association class (III or IV); (p = 0.0001), older age (> 56 years; p = 0.0001), and lower (< 0.56) ejection fraction (p = 0.0001). Freedom from thromboemboli and anticoagulant-related bleeding at 5 years was 90.8% and 98.7%, respectively. Univariate model for greater risk of late thromboemboli identified female sex (p = 0.04), older age (> 56 years; p = 0.0002), and New York Heart Association class III or IV (p = 0.0058), as risk factors. Multivariate analysis for thromboemboli demonstrated older age (p = 0.0007) and New York Heart Association class III or IV (p = 0.0041) as significant. Alternatively, univariate analysis for late bleeding found only the most recent operative interval (p = 0.009) as significant, and the rarity of events prevented a multivariate query. There were no valve failures. CONCLUSIONS: The late results of survival and freedom from late anticoagulant-related bleeding or thromboemboli are excellent, especially in larger (9A and above) sizes, and with the long implant record comparable with more recent prostheses, the Starr-Edwards valve provides an excellent, safe, and durable alternative in the aortic position and provides a benchmark against which to compare other prostheses.

Anticoagulants↗

PubMed1997

Aortic valve replacement after repair of pulmonary atresia and ventricular septal defect or tetralogy of Fallot.

OBJECTIVE: Little attention has been paid to the occurrence of aortic regurgitation after complete repair in patients with pulmonary atresia and ventricular septal defect or tetralogy of Fallot. To highlight the development of aortic regurgitation or aortic root dilation severe enough to necessitate aortic valve replacement with or without aortic aneurysmorrhaphy or aortic root replacement, we retrospectively reviewed the records of patients who underwent aortic valve operation at our institution subsequent to repair of pulmonary atresia and ventricular septal defect or tetralogy of Fallot. METHODS: We searched the Mayo Clinic database for patients with pulmonary atresia and ventricular septal defect or tetralogy of Fallot who subsequently had aortic valve or aortic root operations. The degree of aortic regurgitation before operation was noted. Aortic sinus and root dimensions were measured. RESULTS: Sixteen patients underwent complete repair at a median age of 17 years, followed by an aortic operation a median of 13.5 years later. All 16 patients had dilated aortic sinuses at the time of the aortic valve operation. These 16 patients had aortic valve replacement: 11 with mechanical prostheses and 5 with bioprostheses. Five of the 16 also had reduction of aortic dilation by lateral aneurysmorrhaphy, and 1 had graft replacement of the ascending aorta. Five patients had associated conditions (evidence of valvular damage, recurrent ventricular septal defect, or history of endocarditis) discovered at the aortic valve operation that have been reported to be related to the development of aortic regurgitation. The remaining 11 patients had progressive aortic regurgitation despite complete, uncomplicated repair. CONCLUSIONS: Progressive aortic regurgitation and aortic root dilation can occur despite complete repair of pulmonary atresia and ventricular septal defect or tetralogy of Fallot.

Adolescent↗

PubMed1997

Results of allograft aortic valve replacement for complex endocarditis.

METHODS: Between November 1985 and July 1995, 36 patients underwent allograft aortic valve replacement for endocarditis. The mean age of the 29 men and seven women was 53 years (range 25 to 79 years). Previous procedures included mechanical (n = 9), bioprosthetic (n = 5), and allograft (n = 2) aortic valve replacement, aortic valvotomy (n = 1), and orthotopic heart transplantation (n = 1). Infecting organisms were Staphylococcus and Streptococcus species in 69% of patients and fungi in 6%. Intraoperative findings demonstrated valvular vegetations (n = 25), annular abscesses (n = 25), and cusp destruction (n = 13). Complex reconstruction of the aortic anulus was required in 25 patients, and associated procedures included mitral valve repair (n = 2), mitral valve replacement (n = 3), coronary artery bypass grafting (n = 8), repair of ventricular septal defect (n = 4), left ventricular aneurysmectomy (n = 1), and repair of atrial septal defect (n = 1). Allograft valve insertion was performed by the scalloped technique in seven, intraaortic cylinder technique in 19, and allograft aortic root replacement in 10. RESULTS: Follow-up was 100% complete at a mean of 2.6 +/- 2.8 years after valve replacement. Operative mortality was 13.8%. Complications included low cardiac output (n = 10), bleeding (n = 2), myocardial infarction (n = 1), stroke (n = 1), renal insufficiency (n = 2), respiratory insufficiency (n = 3), and heart block (n = 8). Late echocardiogram (mean 2.6 +/- 1.8 years) demonstrated grade III/IV aortic regurgitation in five patients. There were seven late deaths (five cardiac, not valve-related; two noncardiac). No patient has had recurrence of endocarditis. Actuarial survival at 5 years was 53.1% +/- 11.5%. Univariate analysis demonstrated prosthetic valve endocarditis to adversely affect late survival (p = 0.04). Cumulative risk of reoperation at 5 years was 8.0% +/- 5.6%. CONCLUSION: Allograft aortic valve replacement facilitated reconstruction of complex aortic valve endocarditis with a low reoperation rate and no recurrent endocarditis in this series.

Adult↗

PubMed1997

The Fontan procedure for pulmonary atresia with intact ventricular septum: operative and late results.

OBJECTIVES: The goals of the study were to evaluate the operative and late mortality associated with the Fontan procedure in patients with pulmonary atresia and an intact ventricular septum and to obtain follow-up information on the current clinical status of surviving patients. BACKGROUND: Between 1979 and October 1, 1995, 40 patients with the anomaly had a nonfenestrated Fontan procedure performed at the Mayo Clinic. Because there are no previously published reports involving a series of this size in which the Fontan approach was used for this condition, a review of patient outcomes was thought to be of value. METHODS: The medical records of the 40 patients were reviewed retrospectively, and 34 were determined to be alive. The status of the survivors as of late 1995 was then ascertained by direct examination, questionnaire or telephone follow-up. RESULTS: There were three operative deaths and three late deaths. The current ages of the 34 survivors ranged from 4 to 30 years (median 13). Thirty-three of the 34 survivors were thought to be in New York Heart Association functional class I or II, and all but three of these patients, of school age or older, were either full-time students or working full time. The three adults who were not employed thought they were capable of working but were not doing so because of socioeconomic reasons. More than half of the patients were not receiving cardiovascular medications. CONCLUSIONS: These overall gratifying early and late results encourage continued application of this operation for appropriately selected patients with this complex congenital cardiovascular anomaly.

Adolescent↗

PubMed1997

Exercise tolerance in patients with Ebstein's anomaly.

OBJECTIVES: The purpose of this study was to identify the determinants of exercise tolerance in patients with Ebstein's anomaly. BACKGROUND: Patients with Ebstein's anomaly of the tricuspid valve may have exercise limitation that improves after surgical repair. METHODS: One hundred seventeen patients performed cycle ergometry for a total of 124 tests (preoperative test in 76 patients, postoperative test in 23, test but no operation in 18, preoperative and postoperative test in 7). Multiple linear regression analysis was used to identify predictors of maximal oxygen uptake, oxygen saturation and heart rate at peak exercise. RESULTS: Age at the time of exercise ranged from 6 to 60 years (median 15). An atrial septal defect was present in 67 patients (88%) preoperatively. Compared with the preoperative group, the postoperative group had significantly higher maximal oxygen uptake (mean [+/- SD] 20.5 +/- 7.4 vs. 25.3 +/- 7.0 ml/kg body weight per min, p = 0.006). Postoperative rest and exercise blood oxygen saturation was higher than that measured preoperatively (p = 0.0001). Six of seven patients tested before and after the operation showed improved exercise tolerance. Preoperatively, major predictors of maximal oxygen uptake were oxygen saturation at rest (p = 0.01) and age (p = 0.0001). Preoperatively, the major predictor of oxygen saturation at peak exercise was rest oxygen saturation (p = 0.0001), and major predictors of peak exercise heart rate were rest heart rate (p = 0.01) and rest oxygen saturation (p = 0.01). In the postoperative group, predictors of maximal oxygen uptake included age at exercise testing, male gender and heart size. CONCLUSIONS: Definitive operation for Ebstein's anomaly results in improved exercise tolerance. Before the operation, rest oxygen saturation is the major predictor of exercise tolerance, oxygen saturation at peak exercise and peak heart rate. Postoperatively, age, gender and heart size influenced maximal oxygen uptake.

Adolescent↗