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Biomedical subjects

F J Puga

Publications and source records attributed to F J Puga.

At least 163 records · Page 9Linked to original sources
PubMed1983

Coronary artery compression with fatal myocardial ischemia. A rare complication of valved extracardiac conduits in children with congenital heart disease.

Three children with congenital heart disease died after surgical procedures involving the placement of valved extracardiac conduits; their deaths were caused by myocardial ischemia following coronary artery compression by the metallic stent of the conduit valve. The first and second patients died of acute myocardial ischemia or infarction during the immediate postoperative period, whereas the third patient died of chronic myocardial ischemia and progressive heart failure several months after the operation. In a fourth patient the problem of possible coronary artery compression was suspected on completion of the surgical procedure, and the valve stent was then repositioned away from the coronary artery; this resulted in marked hemodynamic improvement. Fatal myocardial ischemia from coronary artery compression is a rare but potential complication of valved extracardiac conduit placement in children with congenital heart disease. Preoperative assessment of coronary artery distribution is indicated in those patients with prior intrapericardial operations and subsequent pericardial adhesions. Such assessment in previously unoperated patients may be undertaken at the time of conduit operation. Proper conduit placement and intraoperative recognition of possible coronary artery compression by the conduit are important in preventing significant ischemic complications.

Child↗
PubMed1983

Double-outlet right ventricle. Surgical results, 1970-1980.

Between Jan. 1, 1970, and Jan. 1, 1980, 62 consecutive patients underwent repair of classic double-outlet right ventricle (DORV). Patients with subpulmonic ventricular septal defect (VSD), complete atrioventricular canal, atrioventricular discordance, and univentricular heart were excluded. One hundred six associated defects were present in 54 patients. Forty-six patients had pulmonary stenosis. The 36 male and 26 female patients ranged in age from 8 months to 37 years (median age 9 years). The early mortality was 11% for those with pulmonary stenosis, 25% for those without pulmonary stenosis, and 15% for the entire series. The risk of mortality was related to the age of the patient at operation. Causes of early deaths included low cardiac output (three patients), high residual right ventricular pressure (three patients), anomalous coronary artery injury (one patient), infection (one patient), and hemorrhage (one patient). Eleven late deaths occurred among the 53 operative survivors (21%). Ten (91%) of the late deaths were attributed to arrhythmia. All except one of the long-term survivors are in Functional Class I or II. Although the operative mortality for the repair of DORV continues to decrease, the late mortality is of concern, and the problem of late arrhythmia necessitates further study and analysis.

Adolescent↗
PubMed1983

Enlargement of the aortic root or anulus with autogenous pericardial patch during aortic valve replacement. Long-term follow-up.

Patch enlargement of the aortic root or anulus is a widely accepted technique when restrictive anatomy is encountered during aortic valve replacement. Patches made of prosthetic material have been used almost exclusively, and patches of autogenous pericardium have not received wide acceptance. Although pericardium is advantageous because of its low cost, ready availability, and ease of handling, its long-term durability has not been fully established. From 1965 to 1981, 96 patients had autogenous pericardial patches placed during aortic valve replacement at the Mayo Clinic. In 81 patients, the patches were placed solely in a supravalvular position to facilitate aortic closure, while in 15 patients, the patches were placed in both subvalvular and supravalvular positions, allowing for annular expansion and insertion of a larger prosthesis. In a mean follow-up of 5.4 years, none of the 92 operative survivors has had clinical evidence of sudden patch failure and none has had patch aneurysms detected by routine chest roentgenography. One patient required reoperation for a perivalvular leak at the point where the prosthesis had been sutured to the patch. Objective data concerning the late postoperative status of the patch were available on 48 patients: 24 underwent reoperation, 16 underwent two-dimensional echocardiography, two underwent aortic root angiography, and six underwent postmortem examination. Patch aneurysms were universally absent, and in every patient the patches were well incorporated into the adjacent tissues. This proven durability suggests that autogenous pericardium is a satisfactory patch material when required during aortic valve replacement.

Adolescent↗
PubMed1982

A platelet-inhibitor-drug trial in coronary-artery bypass operations: benefit of perioperative dipyridamole and aspirin therapy on early postoperative vein-graft patency.

To prevent occlusion of aortocoronary-artery-bypass grafts, we conducted a prospective, randomized-double-blind trial comparing dipyridamole (instituted two days before operation) plus aspirin (added seven hours after operation) with placebo in 407 patients. Vein-graft angiography was performed in 360 patients (88 per cent) within six months of operation (median, eight days). Within one month of operation, 3 per cent of vein-graft distal anastomoses (10 of 351) were occluded in the treated patients, and 10 per cent (38 of 362) in the placebo group; the proportion of patients with one or more distal anastomoses occluded was 8 per cent (10 of 130) in the treated group and 21 per cent (27 of 130) in th placebo group. This benefit in graft patency persisted in each of over 50 subgroups. Early postoperative bleeding was similar in the two groups. In this trial dipyridamole and aspirin were effective in preventing graft occlusion early after operation.

Adult↗
PubMed1982

Late results after extracardiac conduit repair for congenital cardiac defects.

Analysis of the late results in 352 patients surviving insertion of an extracardiac conduit before mid 1977 has provided a mean follow-up interval of 65 months. Three fourths of the patients remain in improved condition after operation. Serial measurements of transconduit gradient are available in 90. The median change was +7 mm Hg and the mean +21 mm Hg. Reoperation was required in 16 percent of patients (mortality rate 9 percent), most commonly (77 percent) because of progressive conduit stenosis, more commonly for transposition of the great arteries than for other types of anomalies, and more commonly after use of a homograft aortic conduit than a Hancock conduit. The side of the aorta on which the conduit was placed exerted no significant influence. The postrepair transconduit gradient did not affect the need for reoperation. Late survival was 95 percent at 1 year, 85 percent at 5 years, and 73 percent at 10 years and was significantly better (probability [p] less than 0.006) for patients with pulmonary atresia than for the others. The hospital mortality rate was highest, and the late mortality rate lowest, for children less than 5 years of age; the overall survival rate in this age group was lower. The postrepair right ventricular to left ventricular pressure ratio, together with age, was a principal prognostic indicator of late survival, being less good when more than 0.73. THe most frequent causes of late death were progressive congestive heart failure and sudden death.

Adolescent↗
PubMed1982

Partial atrioventricular canal defect in adults.

Between March 1955 and March 1981, 52 adult patients (age 20 years or older) with partial atrioventricular canal (PAVC) were examined at the Mayo Clinic. Forty patients were in New York Heart Association (NYHA) functional class I or II. The ECG showed right bundle branch block with left-axis deviation in 48, first-degree atrioventricular block in 33 and atrial fibrillation in nine. Preoperative catheterization was done in 37 patients; the mean pulmonary resistance index was 2.8 U.m2, and the mean pulmonary-to-systemic flow ratio was 3.0. Forty-seven patients underwent operation; two required mitral valve replacement. There were three operative deaths (6.4% operative mortality) and two late deaths. All surviving patients were in NYHA class I or II. No patient required subsequent permanent pacemaker implantation. We conclude that repair of PAVC in adults may be performed at low risk and may improve patient longevity and functional status.

Adult↗
PubMed1982

Pathogenesis of nonobstructive fibrous peels in right-sided porcine-valved extracardiac conduits.

An autopsy study was conducted of 14 cardiopulmonary specimens in which porcine-valved extracardiac conduits had been placed from the right ventricle to the pulmonary artery. The gross and light microscopic appearance of the tissue lining in such conduits was evaluated. In no instance was the lining considered obstructive. The conduits had been in place for varying lengths of time ranging from 1 day to 5 years. The neointima appeared to begin developing as early as the first postoperative day as a thin layer of platelet-fibrin thrombus, followed by incorporation of red blood cells and a few leukocytes. Between 2 to 3 weeks postoperatively, such shallow thrombotic linings had become organized by fibroblastic migration and proliferation from both the proximal and distal anastomosis sites. However, incomplete development of the neointima frequently led to fenestrations. Peels, or neointimae, older than 1 month did not change, having densely fibrous luminal surfaces and having thrombus or necrotic thrombotic debris along the interface between the conduit and peel. These findings support the concept that progressive thickening of the lining peel takes place primarily along the interface between the peel and the conduit rather than the interface between the peel and the lumen.

Adolescent↗
PubMed1982

Imaging of platelets in right-sided extracardiac conduits in humans.

As a connection between the systemic venous ventricle and the pulmonary artery, valved Dacron extracardiac conduits have remarkably influenced the surgical approach to many complex congenital heart defects. Obstruction of the conduit, however, can reduce the long-term effectiveness of this corrective procedure. In addition to stenosis of the porcine valve, formation of thick fibrous neointima plays a major role in the pathogenesis of conduit obstruction. The purpose of this study was to determine whether platelet deposition could be demonstrated in these conduits by external imaging with In-111-labeled autologous platelets. After injection of labeled platelets either immediately after operation or on the fifth to eighth postoperative day, imaging was performed by standard procedures. Eight of nine patients had platelet accumulation in the conduit, and treatment with aspirin and dipyridamole caused no recognizable change in platelet deposition. This study demonstrates the feasibility of imaging platelet deposition in Dacron conduits and shows that the pattern of deposition varies with time.

Adolescent↗
PubMed1982

Acute postoperative obstruction of extracardiac conduit due to separation of thin fibrous peel.

Late postoperative obstruction of extracardiac conduits may occur in some patients and may result from one of several mechanisms. Severe intraoperative or early postoperative obstruction of such conduits is very rare. Herein we describe a case of acute, severe, early postoperative obstruction of an extracardiac conduit; this followed partial excision and replacement of a Hancock conduit in which late postoperative calcific valvular stenosis had occurred. Unexpectedly elevated right ventricular pressure should suggest the possibility of acute conduit obstruction. In cases with partial conduit replacement, the remaining segment should be carefully inspected for the presence of a peel; if a peel is present, it should be removed from the conduit even if it is considered thin and nonobstructive.

Adolescent↗
PubMed1982

Reoperation after correction of tetralogy of Fallot.

Forty-one patients underwent reoperation after total correction of tetralogy of Fallot from 1962 through 1979. The indications for surgical repair were recurrent or residual lesions alone or in combination with other lesions. The reoperation consisted of closure of a residual ventricular septal defect (VSD) in 28 patients, relief of residual right ventricular outflow tract (RVOT) gradient in 11, tricuspid value replacement, repair or annuloplasty in six, aneurysmorrhaphy or excision of an RVOT aneurysm in five, insertion of a right ventricular-pulmonary artery valved conduit in five, insertion of an RVOT valve in three, closure of a patent foramen ovale or atrial septal defect in three, repair of a residual surgical shunt in three, mitral valve replacement in one patient, and aortic valve repair in one. Thirty-eight patients (93%) survived the operation. The surgical mortality decreased from 25% during 1962 through 1970 to 0% during 1971 through 1979 (p = 0.02). There was one late death. Five patients (12%) required a second-reoperation for recurrent VSD. Even a small residual shunt, especially when associated with other defects such as pulmonary insufficiency or tricuspid insufficiency, may cause clinical deterioration that can be improved by reoperation. This study tends to support the policy of recommending reoperation when either RVOT obstruction (gradient greater than or equal to 50 mm Hg) or isolated VSD (Qp/Qs greater than 1.5) is present. Reoperation is associated with a low mortality and good long-term results.

Adolescent↗
PubMed1982

Left ventricular wall thickness in complete transposition of the great arteries.

Age-related changes in left ventricular wall thickness were studied in 92 autopsy specimens of complete transposition of the great arteries (TGA) and in 189 normal hearts. By means of morphologic and clinical hemodynamic criteria, three groups were defined: Group II, TGA with intact ventricular septum (low left ventricular pressure): Group II, TGA with ventricular septal defect but without pulmonary stenosis (systemic left ventricular pressure combined with volume overload); and Group III, TGA with ventricular septal defect and pulmonary stenosis (systemic left ventricular pressure). At birth, the left ventricular thickness for the three groups did not significantly differ from normal. In group I, the left ventricular thickness remained constant with age up to 4 years and, accordingly, was significantly less after 4 months of age than that both in normals and in Groups II and III. In those Group II specimens from patients without irreversible pulmonary vascular disease, the left ventricular thickness was similar to that of normal hearts. The left ventricular thickness in Group III increased, with age in a manner similar to that of normal hearts. If left ventricular wall thickness correlates with potential ventricular function, then this measurement, combined with other clinical data, may help to predict the ability of the left ventricle to perform systemic work following one of the arterial switch operations. Sequential determinations of wall thickness may be attained noninvasively by echocardiography.

Age Factors↗
PubMed1982

Porcine heterograft valve replacement in children.

From 1973 to 1980, 49 patients under 18 years of age survived cardiac valve replacement with Hancock porcine heterografts. Complete follow-up has been obtained on 44 patients (90%) in whom 46 valves were placed. There were 30 boys and 14 girls with an age range of 2 to 18 years (mean 10.0 years). Severe prosthetic valvular dysfunction requiring valve replacement occurred in eight valves in seven patients at 15 to 60 months postoperatively (mean 34.1 months), yielding a calculated replacement rate of 7.1% per patient-year. All eight valves demonstrated severe calcification with stenosis, two valves had significant insufficiency secondary to leaflet disruption, and one valve had a large leaflet perforation. Thirty-one patients with valves in place at 7 to 90 months (mean 38.4 months) are alive, but six have clinical evidence of progressive valvular dysfunction. The mean age at the time of the original Hancock valve placement of the group of patients having undergone replacement of a failed prosthesis together with those with clinical evidence of prosthetic dysfunction was 8.0 years, which is significantly less than that of the remaining group of patients with normally functioning valves (mean 11.2 years, p = 0.043). Actuarial curves demonstrate a predicted replacement-free rate of 87.4% +/- 5.9% at 3 years. 82.3% +/- 7.5% at 4 years, and 58.5% +/- 15.7% at 5 years. On the basis of these data and other reports of early failure in the literature, we have discontinued the routine use of Hancock porcine heterografts for cardiac valve replacement in children in favor of mechanical prostheses.

Actuarial Analysis↗
PubMed1981

Clinicopathological correlates of obstructed right-sided porcine-valved extracardiac conduits.

Thirteen of 308 patients (4.2%), who had received right-sided valved extracardiac conduits at the Mayo Clinic from November, 1972, to April, 1977, have required conduit replacement because of obstruction. Patients were 5 to 16 years old at initial operation and 8 to 20 years old at reoperation; the duration of conduit implantation was 27 to 79 months (mean 50). Four patients (31%) were asymptomatic; exertional dyspnea was present in eight (62%) and dizziness was reported in one (8%). Signs of conduit obstruction included increasing intensity of murmurs in 11 (85%), cyanosis in two (15%), and heart failure in one (8%). Peak pressure gradients from the right ventricle to the pulmonary arteries ranged from 50 to 140 mm Hg (mean 87) and correlated well with the degree of conduit obstruction. Catheter pullback allowed accurate localization of stenosis within the conduit, whereas angiography alone did not. The site of major obstruction was in the proximal conduit in five (38%), at the valve in nine (69%), and in the distal conduit or side branches in six (46%); stated differently, major stenosis affected the valve alone in five (38%), the graft alone in four (31%), and both the valve and the graft in four (31%). Valvular changes leading to stenosis included thrombosis, commissural fusion, and calcification, and changes consistent with insufficiency included tears, fusion of cusps to the conduit wall, and, in one case, infective endocarditis. Within the conduit, nonvalvular obstruction was due to formation of a thick fibrous peel (or neointima). Progressive thickening of the peel appeared to be due to organization of thrombus between the peel and conduit and not due to luminal mural thrombus. In one case, the peel formed a flap-valve, causing even further obstruction. Since many patients are asymptomatic, and since late conduit stenosis may develop unpredictably by several mechanisms, long-term follow-up is necessary.

Adolescent↗
PubMed1981

Intra-aortic balloon counterpulsation as adjunct to aneurysmectomy in high-risk patients.

Patients with severe coronary artery disease that is not amenable to coronary artery bypass surgery face formidable risks when major aortic surgery becomes necessary. In this report we present such a patient, who successfully underwent abdominal aortic aneurysm resection and graft replacement with the prophylactic use of intra-aortic balloon counterpulsation. The use of intra-aortic balloon counterpulsation at the time of surgery has the potential of improving cardiac function in patients with left ventricular dysfunction and favorably influencing the perioperative and postoperative mortality in these patients. Its use also appears worthy of trial in patients with ruptured abdominal aortic aneurysm and shock, in the hope that it will result in improved survival in these patients.

Aorta, Abdominal↗
PubMed1979

Primary cardiac myxosarcoma in a child.

This is a detailed clinical and autopsy documentation of a rare entity--primary cardiac myxosarcoma in a 29-month-old girl. The patient had sudden onset of right hemiplegia and angiographic evidence of multiple occlusions of the left middle cerebral artery. Subsequent M-mode and sector echocardiography showed a mobile, pedunculated left atrial tumor, which was excised. No other tumor mass was noted at the time of surgical exploration, and postoperatively, the patient received a course of chemotherapy (vincristine, dactinomycin, and cyclophosphamide). After a temporary improvement in her condition, the patient died following several days of rapid deterioration; this was 3 months after the onset of symptoms. Autopsy showed that death was due to brainstem herniation secondary to massive infiltration of the brain by tumor, and there were also widespread systemic metastases.

Brain↗