Search PubMed⌕ Search

Biomedical subjects

F J Puga

Publications and source records attributed to F J Puga.

At least 145 records · Page 8Linked to original sources

Clinical and therapeutic aspects of Haemophilus influenzae pericarditis in pediatric patients.

Two cases of Haemophilus influenzae type B pericarditis are presented which demonstrate the major clinical features and sequelae of this serious illness. These cases are analyzed together with 77 others from the literature to characterize the clinical features, natural history, and optimal therapy. H. influenzae pericarditis is an increasingly frequent disease of young children. A mild prodromal illness is often followed by rapid progression of cardiac compromise until death ensues, unless pericarditis is diagnosed and treated appropriately. The development of cardiomegaly in a febrile patient with a Haemophilus infection is an indication for echocardiography, which is diagnostic of the pericardial effusion. Initial cultures of pericardial aspirates will be positive in 75% of cases even when antibiotic therapy has been initiated. Use of appropriate parenterally administered antibiotics, in combination with early surgical pericardial drainage or partial pericardiectomy, should minimize morbidity and mortality and prevent acute constrictive sequelae.

Anti-Bacterial Agents↗

Intracellular calcium transients in human working myocardium as detected with aequorin.

The calcium transients associated with contraction in human working myocardium were recorded by use of the bioluminescent protein, aequorin, a substance that emits light when it combines with calcium ion (Ca++). Small amounts of aequorin were microinjected into superficial cells of human atrial and ventricular muscle obtained from tissue routinely excised and discarded at the time of cardiac surgery. Light output, an index of intracellular Ca++, and isometric tension development were recorded at 37.5 degrees C at 1 to 5 second intervals of stimulation. Light increases much more quickly than tension and decreases toward basal levels by the time that peak tension is reached. The configuration and time course of the aequorin signal in human myocardium and its responses to inotropic interventions are similar to those recorded in lower mammalian species. The calcium transient appears to be dominated by the release and uptake of Ca++ from intracellular stores under all conditions studied. These results indicate that aequorin is a useful tool for studying the effects of drugs and disease states on cardiac excitation-contraction coupling in human beings as well as in lower animals.

Aequorin↗

Functional single ventricle: cardiorespiratory response to exercise.

The cardiorespiratory response to exercise was measured in 27 children with functional single ventricle. All 27 patients had a significant reduction in exercise time, work performed, maximal exercise heart rate, maximal oxygen uptake and systemic arterial blood oxygen saturation. The reduction in exercise performance increased with increasing age of the patients. All patients ventilated excessively at rest and during exercise. This study documented the precise level of exercise intolerance in patients with functional single ventricle. The progressive deterioration in exercise performance with increasing patient age may lend credence to the concept that operation for physiologic correction of functional single ventricle should be considered during or before adolescence.

Adolescent↗

Surgical repair of univentricular heart (double inlet left ventricle) with obstructed anterior subaortic outlet chamber.

The results of operation in all patients with univentricular heart and an obstructed anterior subaortic outlet chamber who were operated on utilizing extracorporeal circulation at the Mayo Clinic from 1973 through 1983 were reviewed. Ten of the 18 patients died during the immediate postoperative period and there was one late death. Factors significantly related to operative and immediate postoperative mortality were age at operation, cardiothoracic ratio on X-ray examination, degree of ST depression on electrocardiogram and pressure gradient across the outlet foramen at catheterization. Autopsy in eight cases revealed significant hypertrophy of ventricular myocardium and a small outlet foramen that was considered stenotic relative to either body surface area or aortic root area. The ventricular myocardium showed histologic changes of chronic ischemia that predated the surgical procedure.

Adolescent↗

Complete atrioventricular canal associated with tetralogy of Fallot. Morphologic and surgical considerations.

Between 1962 and 1979, 14 patients with complete atrioventricular canal and tetralogy of Fallot underwent repair of both anomalies. The ages of the patients ranged from 1 to 12 years. Six patients had Down's syndrome. Five of the 14 had one or more previous systemic-pulmonary artery shunts. The correct diagnosis was established preoperatively in 11 of the patients. The ventricular septal defect, with its large anterior subaortic extension, was repaired by a combined atrial and right ventricular approach in five patients and by an atrial approach alone in nine. Outflow tract reconstruction (transannular patch) was performed in seven patients, without affecting the surgical mortality. Mortality was higher with associated Down's syndrome, but not significantly so (p = 0.1), and was related to age less than 4 years (p = 0.04). The presence of complete atrioventricular canal should be considered in patients with tetralogy of Fallot, especially those having Down's syndrome, electrocardiographic superior-axis deviation, and vectorcardiographic counterclockwise frontal QRS loop. This diagnosis can be confirmed preoperatively by right and left ventricular angiocardiography and two-dimensional echocardiography. The overall risk of repair has been high (29% early, 14% late mortality), but the mortality has been reduced to 17% during the last 10 years. No deaths have occurred in five recent patients who underwent closure of the ventricular septal defect by a combined atrial and ventricular approach.

Abnormalities, Multiple↗

Reoperation for obstructed pulmonary ventricle-pulmonary artery conduits. Early and late results.

Obstruction of pulmonary ventricle-pulmonary artery conduits can result from neointimal peel formation or valvular degeneration and calcification. To determine the risks and outcome of reoperation, we reviewed the records of 100 consecutive patients who had replacement of severely stenotic pulmonary ventricle-pulmonary artery conduits. At reoperation, the 70 male and 30 female patients had a mean age of 13.3 +/- 4.8 years. During operation, 37 homografts, 62 Dacron grafts with integral xenograft valves, and one nonvalved conduit were replaced with valved (80) or nonvalved (17) prostheses. The mean transconduit pressure gradient decreased from 81 +/- 26 mm Hg preoperatively to 7 +/- 8 mm Hg postoperatively (p less than 0.01). Concomitant cardiac valve replacement was performed in seven patients, and residual ventricular septal defect closure was accomplished in 28. Operative mortality (less than 30 days) was 7%, but there were no deaths among the 47 patients who had no associated defects. At 3 and 5 years postoperatively, probability of survival among patients dismissed from the hospital was 94% +/- 3% and 86% +/- 6%, respectively. In our experience, risk of reoperation for conduit obstruction alone is low, so that the effect of graft failure on overall survival is minimized.

Adolescent↗

Late results after Starr-Edwards valve replacement in children.

Selection of types of prosthetic heart valves for children remains controversial. The case histories of 50 children surviving valve replacement with Starr-Edwards prostheses between 1963 and 1978 were reviewed to evaluate the long-term performance of mechanical valves. The 31 boys and 19 girls ranged from 6 months to 18 years in age (mean 10.4 years); 19 patients had had aortic valve replacement, 24 patients had had mitral valve replacement, and one patient had had both. Among the six patients who had had tricuspid valve replacement, four had corrected transposition, so that the tricuspid valve was the systemic atrioventricular valve. Mean (+/- standard deviation) follow-up interval was 7.9 +/- 4.9 years (maximum 17 years). For all patients, the 5 year survival rate was 86% +/- 6%. At 10 years postoperatively, the survival rate (+/- standard error) was 90% +/- 7% after aortic valve replacement and 76% +/- 8% after systemic atrioventricular valve replacement. At follow-up, 39 patients were alive, and 38 were in New York Heart Association Class I or II. Of the 11 deaths, four were valve-related. Seven patients had major (requiring hospitalization) thromboembolic events, and five patients had minor transient neurological symptoms suggesting thromboembolism; 50% of these patients were not taking warfarin (Coumadin) at the time of the thromboembolic event. The incidence of late (greater than 30 days) thromboembolism was 5.3 per 100 patient-years after aortic and 2.0 per 100 patient-years after systemic atrioventricular valve replacement. At 10 years postoperatively, 66% +/- 15% of patients who had had aortic valve replacement and 91% +/- 6% of those who had had systemic atrioventricular valve replacement were free of thromboembolism. The excellent long-term survival, absence of mechanical failure, and relatively low rate of thromboembolism with this prosthesis contrast with our experience with biological valves, in which 41% of children required reoperation in 5 years. Currently, mechanical valves, such as the Starr-Edwards prostheses, are our preferred valves for pediatric patients.

Adolescent↗

Surgery for tricuspid regurgitation late after mitral valve replacement.

Tricuspid valve insufficiency may contribute to a poor hemodynamic result after mitral valve replacement. To determine the role of surgical treatment, we have reviewed the records of 32 adult patients who underwent tricuspid valve repair or replacement 4 months to 14 years after mitral valve replacement. Mild tricuspid valve insufficiency at the time of mitral valve replacement was present in 21 patients (66%); 26 patients (81%) had New York Heart Association class IV disability. Tricuspid annuloplasty was performed in 16 patients, and the remainder received various prosthetic valves. Concomitant repair of mitral valve periprosthetic leak and/or replacement of the aortic valve was necessary in 18 patients (53%). Hospital mortality was 25%, and all early deaths were related to low cardiac output. Among hospital survivors there have been 14 late deaths for 3 and 5 year actuarial survival rates of 65% and 44%. Twelve of the 14 patients who died late and one of 10 patients who were alive at the end of the follow-up period had little or no functional improvement after tricuspid valve repair or replacement. The high early and late mortality and poor functional outcome for patients undergoing tricuspid valve surgery late after mitral valve replacement contrast with our good overall results in reoperation for prosthetic heart valves. It appears that serious tricuspid valve insufficiency after mitral valve replacement frequently signals right ventricular failure and dilatation; restoring valve competence is palliative. This experience encourages us to continue our policy of liberal indications for tricuspid valve annuloplasty at initial mitral valve replacement.

Adult↗

Trial of combined warfarin plus dipyridamole or aspirin therapy in prosthetic heart valve replacement: danger of aspirin compared with dipyridamole.

Despite the use of oral anticoagulation in patients with prosthetic heart valves, persistent thromboembolism over time warrants a search for improved methods of prevention. Thus, patients receiving 1 or more mechanical prosthetic heart valves were randomized to therapy with warfarin plus dipyridamole (400 mg/day) or warfarin plus aspirin (500 mg/day) on the basis of location and type of valve and surgeon, and followed up with a concurrent, nonrandomized control group taking warfarin alone. In 534 patients followed up 1,319 patient-years, excessive bleeding (necessitating blood transfusion or hospitalization) was noted in the warfarin plus aspirin group (23 of 170 [14%], or 6.0/100 patient-years) compared with warfarin plus dipyridamole (7 of 181 [4%], or 1.6/100 patient-years, p less than 0.001), or warfarin alone (9 of 183 [5%], or 1.8/100 patient-years, p less than 0.001). A trend was evident toward a reduction in thromboembolism in the warfarin plus dipyridamole group (2 of 181 [1%], or 0.5/100 patient-years) as compared with warfarin plus aspirin (7 of 170 [4%], or 1.8/100 patient-years), or warfarin alone (6 of 183 [4%], or 1.2/100 patient-years). Adequacy of anticoagulation (based on 12,720 prothrombin time determinations) was similar in all 3 groups with 65% of prothrombin times in the therapeutic range (1.5 less than or equal to prothrombin time/control less than or equal to 2.5), 30% too low, and 5% too high. Warfarin plus aspirin therapy resulted in excessive bleeding and is contraindicated. Longer follow-up study is needed to determine whether further separation of the incidence of thromboembolism can be detected.

Aspirin↗

Impact of 2-Dimensional echocardiography on the management of distressed newborns in whom cardiac disease is suspected.

The course and management of 40 consecutive newborns (aged less than 2 weeks) who presented with signs and symptoms of congenital heart disease were reviewed to determine the impact of 2-dimensional (2-D) echocardiography on their subsequent management. Of the 40 patients with congenital heart disease, 60% did not undergo cardiac catheterization. Forty-two percent of the patients who were treated surgically went directly to operation without preoperative cardiac catheterization. Only 40% of the patients with congenital heart disease required cardiac catheterization in the newborn period, and 43% of these procedures were primarily therapeutic (that is, balloon atrial septostomy). In each patient 2-D echocardiography correctly identified the major cardiac malformation and there was good agreement with angiographic, surgical, and autopsy findings. The most commonly overlooked defect was a patent ductus arteriosus. Thus, 2-D echocardiography not only allows diagnosis of congenital heart disease in the newborn but can expedite clinical management. No longer is cardiac catheterization necessarily the primary means for an anatomic diagnosis of congenital cardiac malformations in the newborn.

Angiography↗

Results of reoperation for periprosthetic leakage.

Between 1961 and 1978, 6,602 valves were replaced in 5,660 patients. Reoperation for periprosthetic leakage was performed in 105 patients (1.6% of the valves); early mortality was 5.7%. At reoperation, 52% of patients were in New York Heart Association Classes III and IV, whereas 72% had been in Classes III and IV prior to the primary valve replacement. Seventy-five patients had aortic periprosthetic leaks, which were distributed equally around the annulus. Among these patients, 41 (55%) had aortic valve rereplacement and 34 (45%) had suture repair. At 5 years, the survival was 94% and the event-free survival was 71%. Seventeen patients had multiple aortic valve reoperations. Hospital mortality for the second reoperation was 5.8%. At late follow-up, 19 patients had murmurs of residual or recurrent aortic periprosthetic leakage. Twenty-nine patients had mitral periprosthetic leaks, most often near the anterior leaflet. Eight patients had mitral valve rereplacement, and 21 had suture repair. At 5 years, the survival was 75% and the event-free survival was 52%. Four patients underwent multiple reoperations. At late follow-up, 5 of the 29 patients in the mitral valve group had murmurs of residual or recurrent periprosthetic leakage. One patient had tricuspid valve rereplacement. The low hospital mortality and the good late results have encouraged us to recommend an aggressive approach in the correction of periprosthetic leakage in all symptomatic and selected asymptomatic patients.

Adult↗

Complete repair of pulmonary atresia with nonconfluent pulmonary arteries.

From 1973 through 1979, 16 patients with pulmonary atresia, two normal-sized ventricles, and bilateral but nonconfluent pulmonary arteries underwent complete repair at the Mayo Clinic. Mean age at operation was 9.1 years (standard deviation [SD] 5.2 years). Sources of pulmonary flow were previous surgical shunts, patent ductus arteriosus, and discrete systemic-pulmonary arterial collaterals. The complete surgical repair included interruption of extracardiac shunts, closure of ventricular septal defect (15 patients), closure of atrial septal defect (3 patients), and establishment of right ventricular-pulmonary arterial continuity with a porcine-valved extracardiac conduit anastomosed to a transverse limb (T graft in 12 patients) or to a side-limb (Y graft in 4 patients). There were no operative deaths. Morbidity included reoperation for bleeding in 3 patients and compression of the prosthetic graft by the sternal closure in 1. The mean postrepair ratio of right ventricular peak systolic pressure to left ventricular peak systolic pressure (pRV/pLV) was 0.64 (SD, 0.23). Follow-up ranged from 12 to 72 months (means, 34.6 months; SD, 20.7 months). One patient died 12 months after operation (postrepair pRV/pLV, 1.3). Conduit obstruction has been proved in 4 patients, of whom 3 underwent reoperation for extracardiac conduit obstruction at 46, 47, and 48 months. The remaining 11 patients are alive and free of major symptoms.

Adolescent↗

The morbidity and mortality of reoperation for coronary artery disease and analysis of late results with use of actuarial estimate of event-free interval.

To determine late survival and functional status after second revascularization procedures for coronary artery disease, we studied 106 consecutive patients operated on between June, 1969, and December, 1980. The mean age of the 96 men and 10 women was 49 +/- 8 years (range 22 to 65 years). Before reoperation, 101 patients (95%) were judged to be in New York Heart Association Class III or IV with angina, and 81 patients (76%) had three-vessel involvement. Angina recurrence was most commonly caused by bypass graft occlusion alone and in combination with progressive disease of the native arteries (60 patients, 57%). Three patients (2.8%) died within 30 days of reoperation; each death resulted from myocardial infarction. An average of 2.2 coronary arteries were bypassed in each patient. Complete follow-up data (mean 43 months) were available for 105 patients. Actuarial survival of patients dismissed alive is 94% at 5 years and 89% at 7 years. All late cardiac-related deaths occurred in patients with three-vessel disease. When recurrence of any angina, need for a third operation, and myocardial infarction are included with cardiac-related deaths, event-free survival is 28% at 5 years and 26% at 7 years. Late survival and functional status could not be predicted by the cause of recurrent angina or the presence of risk factors. Repeat myocardial revascularization can apparently be undertaken with low risk and with prospects for excellent long-term survival. After reoperation, recurrence of mild angina is not uncommon, but freedom from serious cardiac events and relief of severe symptoms were noted in more than 60% of patients 5 years later.

Actuarial Analysis↗

Reoperation on prosthetic heart valves. An analysis of risk factors in 552 patients.

Five hundred fifty-two patients underwent a total of 617 reoperations for repair or replacement of a prosthetic heart valve. Operative mortality for first reoperation (530 patients) was 5.9% for the aortic position and 19.6% for the mitral position. Overall operative mortality was 14% for second reoperation (69 patients) and 7% for third reoperation (14 patients). In addition to valve position, operative mortality for first reoperation appeared to be related to pre-reoperation functional class and urgency of operation. First reoperation for mitral valve patients in New York Heart Association (NYHA) Class II was 4.2%; for Class III, 9.3%; and for Class IV, 41%. In the aortic position, operative mortality was 2.4% for Class I, 1.6% for Class II, 6.3% for Class III, and 20.8% for Class IV. The mortality for elective mitral valve reoperation was 0%; for urgent operation, 20.3%; and for emergency procedures, 54.5%. Elective aortic valve reoperation carried a 1.4% mortality; urgent procedures, 8%; and emergency procedures, 37.5%. No significant differences in bleeding complications were noted between reoperations and initial valve replacement. The data appear to suggest that when significant valve dysfunction is first noted, reoperation should be undertaken to minimize operative risk.

Adolescent↗

Septal artery revascularization.

Recurrent angina after coronary artery bypass grafting is due to several factors: graft occlusion, progression of disease, and incomplete revascularization. Of these, incomplete revascularization of diseased but graftable secondary branches of the three major coronary arteries is most amendable to primary surgical treatment. Current operative methods permit endarterectomy or direct bypass grafting (or both) of these smaller vessels. This report details two techniques for revascularization of the anterior septal branch of the left anterior descending coronary artery.

Angina Pectoris↗

Surgical pathology of obstructed, right-sided, porcine-valved extracardiac conduits.

Thirty-seven specimens were available from 39 children and adolescents with congenital heart disease who have had operations at the Mayo Clinic (Rochester, Minn) to replace obstructed Hancock conduits that had been implanted 17 to 93 months (mean, 62 months). Stenosis affected the porcine valve alone in 17 (46%), the synthetic graft alone in 11 (30%), both the valve and the graft in six (16%), and other sites in three (8%). Valvular stenosis resulted from degenerative changes with secondary thrombosis and calcification, whereas insufficiency resulted from cuspid tears, thrombotic adhesions, and endocarditis. Nonvalvular obstruction resulted from progressive thickening of fenestrated neointimae, owing to organization of thrombotic debris lining the interface between the conduit and this tissue. Late postoperative conduit stenosis may develop asymptomatically and unpredictably by several different mechanisms.

Adolescent↗

Modified Fontan procedure in patients with previous ascending aorta-pulmonary artery anastomosis.

The Fontan procedure has proved useful in the surgical treatment of patients with tricuspid atresia, univentricular heart, and other complicated cardiac anomalies. Previous palliation of these patients with ascending aorta-right pulmonary artery anastomosis (Waterston shunt) may impose severe restrictions in the operability of these patients because of severe distortion, narrowing, and scarring of the proximal right pulmonary artery. A modification of the Fontan operation is described in which repair is facilitated by transecting the right pulmonary artery at the site of anastomosis, trimming away the distorted narrowed segment, and anastomosing the resulting cuff to the lateral aspect of the superior vena cava. The right atrial appendage is anastomosed to the rudimentary right ventricle or the main pulmonary artery directly or via a tubular Dacron graft. The technique has been applied successfully in four consecutive cases.

Adolescent↗