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V A Gaudiani

Publications and source records attributed to V A Gaudiani.

At least 19 recordsLinked to original sources
PubMed1996

"Legs" technique for management of widely separated coronary arteries during ascending aortic repair.

BACKGROUND: Widely separated coronary arteries with significantly diseased tissue continues to challenge surgeons repairing ascending aortic aneurysms. METHODS: Occasional troublesome leaks around coronary ostial anastomoses and Cabrol graft thrombosis prompted a change of our operative management of this condition. Collagen-impregnated 8-mm "legs" grafts are used to connect the coronary arteries to the composite graft. Ten patients, aged 14 to 70 years, underwent the operation. RESULTS: The first patient is 15 years after the operation and is symptom free. One patient died of an arrhythmia 1 month after discharge. Eight patients are living and well 11/2 to 4 years postoperatively. CONCLUSIONS: Advantages of direct interposition (legs) grafts are as follows: the coronary arteries are separately perfused and the risk of catastrophic thrombosis from a longer high-volume graft is eliminated. Problems with coronary ostial mobilization are avoided. The technique allows full visualization and hemostatic suture line testing with cardioplegia before aortic declamping. Space constraints with reoperations are easily managed, whereas other techniques may result in graft compression on refilling of the heart and termination of bypass. The technique is carried out with ease and reproducibility, and the availability of new graft material has made it our treatment of choice for ascending aortic composite graft replacement.

Adolescent↗
PubMed1996

It's the patient.

Explore the source record for details and available documents.

Attitude to Health↗
PubMed1991

Comparison of pre- and postoperative conduction patterns in patients surgically cured of atrioventricular node reentrant tachycardia.

Patients with atrioventricular (AV) node reentrant tachycardia characteristically have short and constant retrograde His-atrium conduction times (H2A2 intervals) during the introduction of ventricular extrastimuli. It has therefore been suggested that the tachycardia circuit involves retrograde conduction up an accessory pathway located in perinodal tissue. If the mechanism of surgical cure of AV node reentrant tachycardia is interruption of this accessory pathway, postoperative changes in retrograde conduction would be expected. Thirteen patients with drug-refractory AV node reentrant tachycardia underwent surgery. Preoperatively, H2A2 intervals were short and constant. During AV node reentrant tachycardia, earliest atrial activation was seen near the His bundle and was 0 to 25 ms before ventricular activation in all patients except one. Surgery consisted of dissection of right atrial septal and anterior inputs to the AV node and central fibrous body. Postoperatively, the H2A2 interval remained short and constant compared with preoperative values although it was slightly prolonged (74 +/- 18 versus 61 +/- 21 ms, p less than 0.005). Twelve of the 13 patients are free of tachycardia after 28 +/- 13 months and no patient has had evidence of AV node block. Thus, surgical cure of AV node reentrant tachycardia is highly successful; however, there is no reason to postulate an accessory pathway or use of perinodal tissue as part of the tachycardia circuit and the mechanism of surgical success remains obscure.

Adult↗
PubMed1990

Effect of duration of ventricular fibrillation on defibrillation efficacy in humans.

The currently available automatic implantable cardioverter-defibrillator has proven highly successful for termination of ventricular tachycardia and fibrillation. Newer devices, however, permit lower energy shocks to be delivered initially and longer episodes of arrhythmia to occur before shocks are delivered. These changes may result in longer durations of arrhythmia before successful termination. Little is known about the effects of the duration of ventricular fibrillation on the efficacy of defibrillating shocks. In this study, we examined the efficacy of defibrillating shocks in 22 patients undergoing automatic implantable cardioverter-defibrillator implantation or generator change. Defibrillating shocks ranging from 300 to 600 V (5.9-24.2 J) were delivered in matched pairs after 5 and 15 seconds of ventricular fibrillation. For the 300-V shocks (5.9 J), defibrillation was accomplished in 82% of patients when the shocks were given after 5 seconds of ventricular fibrillation and in only 45% of patients when the shocks were delivered after 15 seconds (p less than 0.01). At higher energies, there was no difference in the efficacy of defibrillation shocks delivered after 5 compared with 15 seconds of ventricular fibrillation. The postshock aortic, systolic, and diastolic blood pressures were significantly lower when the shocks were given after 15 seconds of ventricular fibrillation than after only 5 seconds. We conclude that the duration of ventricular fibrillation affects defibrillation efficacy especially at energies that are relatively low compared with maximal device outputs and that longer episodes of ventricular fibrillation cause more postshock hemodynamic depression. These observations have implications for defibrillation threshold testing at the time of device implantation and for the design and programming of future automatic implantable antitachycardia devices.

Adult↗
PubMed1989

Long-term outcome with the automatic implantable cardioverter-defibrillator.

The automatic implantable cardioverter-defibrillator was implanted in 270 patients because of life-threatening arrhythmias over a 7 year period. There was a history of sustained ventricular tachycardia or fibrillation, or both, in 96% of these patients, 80% had one or more prior cardiac arrests and 78% had coronary artery disease as their underlying diagnosis. The average ejection fraction was 34%, and 96% of these patients had had an average of 3.4 antiarrhythmic drug failures per patient before defibrillator implantation. There were four perioperative deaths and eight patients had generator infection or generator erosion, or both, during the perioperative period or during long-term follow-up. Concomitant antiarrhythmic drug therapy was given to 69% of patients. Shocks from the device were given to 58% of patients. and 20% received "problematic" shocks. The device was removed from 16 patients during long-term follow-up for a variety of reasons. There were 7 sudden cardiac deaths and 30 nonsudden cardiac deaths, 18 of which were secondary to congestive heart failure. The actuarial incidence of sudden death, total cardiac death and total mortality from all causes was 1%, 7% and 8%, respectively, at 1 year, and 4%, 24% and 26% at 5 years. The automatic implantable cardioverter-defibrillator nearly eliminates sudden death over a long-term follow-up period in a high risk group of patients. It has an acceptable rate of complications or problems, or both, and most late deaths in these patients are nonsudden and of cardiovascular origin.

Death, Sudden↗
PubMed1988

Comparison of defibrillation efficacy in humans using a new catheter and superior vena cava spring-left ventricular patch electrodes.

The automatic implantable cardioverter-defibrillator currently utilizes an electrode system that requires a major operation for implantation. Effective defibrillation using an implantable cardioverter-defibrillator catheter positioned transvenously would eliminate the morbidity associated with such surgery. Fifteen patients undergoing defibrillator implantation were studied to compare the efficacy of the catheter with that of the superior vena cava spring (6.7 cm2, anode)-left ventricular patch (13.5 cm2, cathode) electrode system using truncated exponential waveforms with 60% tilt. The catheter is 11F in diameter and tripolar. A distal platinum-iridium tip used for pacing was separated by 4 mm from a middle 4.3 cm2 platinum electrode; these were positioned at the right ventricular apex. The proximal 8.5 cm2 platinum electrode was situated at the superior vena cava-right atrial junction. Defibrillation was performed using the middle (cathode) and proximal (anode) electrodes. Ventricular fibrillation was induced by alternating current six times, and defibrillation shocks of 1, 5, 10, 15, 20 or 25 J were given in random order, first using the catheter and then the spring-patch system. Rescue shocks of higher energy were given if there was failure. Although very low energy levels appeared to be slightly more efficacious when using the spring-patch system, there was no statistically significant difference between the electrode systems for any of the energies tested. Permanent implantation of the catheter would have been suitable in 45% of the patients, as compared with 54% of patients with the spring-patch system (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1988

An improved technique for the internal mammary artery coronary bypass graft procedure.

An improved technique for internal mammary artery graft preparation is described. Following cautery dissection of the internal mammary artery (IMA) pedicle, the pedicle investing fascia is incised to the adventitial level along a single plane. This incision allows the tissue around the internal mammary artery to fall away and severs the muscular constrictions that often surround the internal mammary artery. Balloon calibration is performed to identify remaining constrictions and to relieve internal mammary artery spasm. A shear force limiting gauge insures that the exerted balloon force remains below the level demonstrated to cause intimal damage during electron microscopic studies. This technique allows full internal mammary artery distention without the devascularizing effects of full skeletonization. Distention of the distal internal mammary artery provides an enlarged hood to facilitate suture placement. Elongation of the internal mammary artery during balloon calibration aids in the performance of sequential grafts. This technique has been applied to 793 patients over the past five years. Postcalibration flow rates increased 3- to 18-fold over precalibration flow rates. Two early occlusions occurred during this series, one due to endothelial strippage prior to the development and use of the shear force limiting gauge. Follow-up showed 93.3% of patients to be asymptomatic. This combination of fascial incision and balloon calibration appears to offer safe technical and functional improvements to the performance of the internal mammary artery graft.

California↗
PubMed1986

Autologous pericardium versus a xenograft substitute in myocardial wound healing.

This study compared repair of myocardial wounds covered with autologous pericardium to healing of wounds covered with glutaraldehyde-preserved bovine pericardium in an experimental canine model. Right (RV) and left (LV) full thickness ventriculotomies were made and closed. In the control group (n = 12), the pericardium was closed over the wound; in the experimental group (n = 12), wounds were covered with bovine pericardium. Animals were sacrificed at 14, 21, 28, and 42 days. After excising the pericardium, 6 mm punch biopsies of normal RV, RV wound, normal LV, and LV wound were assayed for hydroxyproline (HPro). Both autologous and bovine pericardium became densely adherent to the wounds. Bovine pericardium was mildly adherent over unwounded areas, while autologous pericardium was usually free. Normal RV contained more than twice as much HPro as normal LV (5.4 +/- 0.57 micrograms/mg vs 1.7 +/- 0.35 micrograms/mg, P less than 0.0002). A gradual rise in HPro over time was seen in both groups, but this increase was statistically significant only at 42 days (P less than 0.05). There was no significant difference in HPro between wounds covered with autologous pericardium and those covered with bovine grafts (P = 0.13) at any of the sample times in this study. In this experimental canine model, the pericardium does not appear to play a prominent role in myocardial wound healing by contributing collagen-producing fibroblasts. Furthermore, the bovine pericardial xenograft becomes densely adherent to LV and RV incisions. In the clinical setting, such may make reoperation more hazardous when the heart has been previously incised or coronary bypass grafts have been constructed.

Animals↗
PubMed1983

Veno-venous allografts: patency, subendothelial proliferation, and the role of platelet-active agents.

Patency and histology of 81 vein allografts and 10 autografts in the canine femoral venous system were compared and the effect of platelet active agents in altering patency rates and subendothelial proliferation in allografts was examined. It was found that allografts thrombose at a predictable interval after operation (18 +/- 7 days) and have significantly worse survival than autografts (P less than 0.001). Platelet-active agents did not alter allograft patency rate of the incidence of subendothelial proliferation in this model.

Animals↗
PubMed1983

Diagnosis and treatment of allograft rejection in heart-lung transplant recipients.

Six patients received heart-lung transplants between March, 1981, and January, 1982. There were four women and two men between 26 and 45 years of age, three with primary pulmonary hypertension and three with congenital heart disease and pulmonary hypertension (Eisenmenger's syndrome). Immunosuppression was primarily with cyclosporin-A, with additional corticosteroid, azathioprine, and rabbit antihuman thymocyte globulin. Six episodes of allograft rejection in four patients (10, 11, 21, 24, 53, and 86 days after transplantation) were detected by means of transvenous endomyocardial biopsy. All patients experienced pulmonary edema early after transplantation (reimplantation response), and two patients required mechanical ventilatory support for allograft rejection at 10 and 11 days. Treatment of rejection consisted of intravenous methylprednisolone (four episodes) or augmented oral prednisone (two episodes), with resolution. No episode thought to be pulmonary rejection has occurred in the absence of cardiac findings. Four patients are alive from 6 to 15 months after transplantation and are functionally normal. Early experience with heart-lung transplantation suggests (1) that allograft rejection can be detected by cardiac findings and successfully treated by augmented corticosteroids, (2) that lung rejection does not occur in the absence of cardiac findings, (3) that the frequency and severity of rejection episodes are not greater than with standard cardiac transplantation, and (4) that the frequency of rejection episodes is highest within the first 60 days after transplantation.

Adult↗
PubMed1981

Long-term survival and function after cardiac transplantation.

Cardiac transplantation now permits prolonged survival for some patients with otherwise fatal heart disease. This report summarizes the hemodynamic and clinical characteristics of 25 patients who have survived five or more years after cardiac replacement. The average age of the patients at the time of operation was 40 +/- 10 (SD) years; 23 were men. The average duration of survival is 6.7 years, and ranges from five to 10.5 years. Annual cardiac catheterization and clinical follow-up were performed to assess systolic cardiac function, coronary anatomy, and quality of extended rehabilitation. We found that among these long-term survivors, the left ventricular ejection fraction remained constant (0.59 +/- 0.08 one year postoperatively, 0.57 +/- 0.09 at most recent study, p = ns). Segmental wall motion measured by fluoroscopic examination of midwall intramyocardial markers also remained normal. Four of 21 (19%) patients with complete longitudinal studies developed significant graft coronary artery disease. Clinical evaluation revealed that the long-term survivors required fewer than one unscheduled admission to the hospital per year. Sixteen of 25 patients (64%) were gainfully employed, and 22 of 25 (88%) enjoyed substantial benefit in terms of extended rehabilitation. These 25 long-term survivors represent 27% of 92 patients transplanted between 1968 and 1975. The actuarial survival rate at five years, of patients transplanted since 1975, is 40 +/- 5%. This increase in survival rate reflects improved techniques of early postoperative management. Cardiac transplantation now offers prolonged survival with good quality of life for selected patients with terminal heart disease.

Adult↗
PubMed1981

Operative treatment of an unresectable tumor of the left ventricle.

A 17-year-old girl presented with an enlarged cardiac silhouette on routine chest roentgenogram. After clinical evaluation, echocardiography, and pericardiocentesis failed to provide a diagnosis, exploratory thoracotomy and biopsy revealed an unresectable left ventricular fibroma. The tumor continued to enlarge and began causing ventricular arrhythmia. Therefore, she underwent cardiac transplantation 2 years after the initial diagnosis was made. She is now alive nd well 18 months following transplantation.

Adolescent↗
PubMed1981

Postinfarction ventricular septal defect: an argument for early operation.

We reviewed our experience with 43 consecutive patients who underwent operations for postinfarction ventricular septal defect to determine optimal time for operative intervention, to identify factors responsible for failure of operative treatment, and to determine long-term survival rates. Patients were referred for operation after expectant medical management had failed or after 6 weeks electively. The operative mortality rate was 42% and ranged from 90% for those who required operation within 1 day of 11% for those underwent surgery after 1 month. In a multivariate discriminant analysis of preoperative variables, we found that inferior infarction with perforation (P less than 0.02) and preoperative multisystem failure (evidenced by abnormal mental status, P less than 0.02) were the major factors correlating with high operative risk. Early operation per se did not affect operative mortality rates. Technical problems with early operation were not a source of major morbidity and mortality. Actuarial long-term survival was good, and 88.5% of survivors were alive 5 years after surgery. Because preoperative multisystem failure is often progressive, we recommend immediate operation for all patients with postinfarction ventricular septal defect unless no deterioration is present. Moreover, because of the high risk of those patients with inferior infarction and perforation, we recommended immediate surgery for this group regardless of symptomatic status.

Aged↗