William F. Northrup

Ten years' experience with the St. Jude Medical valve prosthesis

Records of 1,298 consecutive patients who had received the St. Jude Medical prosthesis were reviewed (713 male and 585 female patients; mean age, 61.79 +/- 13.4 years). Early mortality was 5.7% (74 patients). Ninety-three percent complete follow-up was accomplished for the 1,224 patients who left the hospital (4,306.50 patient-years). One hundred ninety-two of these patients died, a late mortality of 16.9%. Sixty-four patients experienced thromboembolic episodes (17 major and 35 permanent). Twenty-four patients had anticoagulant-related bleeding, 4 had valve thrombosis, 7 had prosthetic valve endocarditis, 9 had paravalvular leak, and 10 underwent reoperation. There was no structural valve failure in this series. Twenty-two of the 118 patients who had valve-related complications died; another 15 patients died of sudden and unknown causes. Therefore, the total number of valve-related deaths was 37. Of those patients who survived, New York Heart Association functional class improved significantly (98% in classes II and III preoperatively and 96% in classes I and II postoperatively). Linearized rates for thromboembolism, valve thrombosis, and anticoagulant-related bleeding were 1.49% +/- 0.19%, 0.09% +/- 0.05%, and 0.56% +/- 0.11%/100 patient-years, respectively. The actuarial estimate of incidence free from all complications, operative death, and valve-related death was 66.9% +/- 8.2% at the end of 9 years. In spite of old age and advanced heart disease, the patients who received the St. Jude Medical prosthesis had very good results over a 10-year period.

St. Jude Medical Prosthesis: Valve-Related Deaths and Complications

Despite the hemodynamic improvement in cardiac valve prostheses, valve-related deaths and complications have remained a substantial source of morbidity and mortality. This follow-up study was carried out in April, 1986, in a group of 816 patients who received 876 St. Jude Medical prostheses between October, 1977, and October, 1984. One hundred fifty-five patients (37%) of the 422 having aortic valve replacement (AVR) and 88 (29%) of the 300 having mitral valve replacement (MVR) had concomitant coronary artery bypass grafting, and 94 patients (12%) had miscellaneous procedures performed in addition to valve replacement. Sixty-three patients died within the operative period, an operative mortality of 7.7%. Follow-up was complete for 98% of the patients; the mean follow-up was 42 months. At that time, 87 more patients had died, a late mortality of 11.9%. There were 13 valve-related deaths (4 in the AVR group, 7 in the MVR group, and 2 in the miscellaneous group); the causes of death were thromboembolism (7), anticoagulant-related hemorrhage (2), valve thrombosis (2), prosthetic valve endocarditis (1), and perivalvular leak (1). There were 37 thromboembolic episodes (1.78/100 patient-years) and 67 anticoagulant-related hemorrhages (3.22/100 patient-years), 46% of which necessitated transfusion. The incidence of valve thrombosis was 0.6% (4 patients). Perivalvular leak and prosthetic valve endocarditis occurred in 7 patients (1.0%) and 5 patients (0.7%), respectively. Reoperation was carried out in 6 patients (0.8%), but only for perivalvular leak. There were no deaths, no complications, and no clinical evidence of malfunction of the prosthetic valve.(ABSTRACT TRUNCATED AT 250 WORDS)

Replacement of the aortic valve in patients under 50 years of age : long-term follow-up of the St. Jude Medical prosthesis

BACKGROUND Aortic valve replacement in the young adult (aged 18 to 50 years) is a choice between a mechanical prosthesis with attendant lifelong anticoagulation or biological prostheses of varying types that may have limited life expectancy in this age group. METHODS The Cardiac Surgical Research Foundation database was accessed to determine long-term outcomes in patients having aortic valve replacement with the St. Jude Medical Valve. This database has been privately maintained since the worlds first St. Jude Medical (SJM) valve implant in 1977. Patients were contacted by questionnaire or by telephone if the survey was not returned. Follow-up was 93% complete. RESULTS From October 1977 through October 1997, 271 patients less than 50 years of age had isolated aortic valve replacement. Follow-up was 1957 patient years. Thirty-day operative mortality was 1.1% with 18 late deaths, 4 of which were valve related. Ninety percent of survivor INR responses indicated a frequency of monthly INR checks or less. Valve-related events including percent per patient year and mortality related to these events included thromboembolism, 6 episodes (0.3% per patient year, no deaths); anticoagulant-related bleeding, 6 events (0.3% per patient year, 2 deaths); paravalvular leak, 6 events (0.3% per patient year, 2 deaths); valve thrombosis, 2 events (0.1% per patient year, no deaths); and endocarditis, 3 events (0.15% per patient year, no deaths). There was no incidence of structural valve failure. CONCLUSIONS The SJM valve has a long record of excellent performance with durability lasting more than 20 years. The incidence of untoward events is low and death over time due to valve-related complications is low (4 of 271). The SJM valve has become our valve of choice for younger patients.

Opposite trends in coronary artery and valve surgery in a large multisurgeon practice, 1979–1999

BACKGROUND Trends in coronary artery bypass (CAB) and valve operations (VO) may help predict the future of cardiac surgery in the context of changing case mix, shifting paradigms, emerging technology, and population demographics. METHODS We retrospectively reviewed all 30,319 adult CAB and VO in our group from 1979 to 1999 according to specific procedures. RESULTS Coronary artery bypass volumes peaked in 1996 at 1,895 cases, declining 15.3% to 1,605 cases in 1999 with a decrease in risk profile and percent reoperations and an increase in mean age and percent octogenarians, prior percutaneous coronary interventions (PCI), left internal mammary artery (LIMA) graft usage, off-pump technology usage, and hospital mortality of reoperations. Right internal mammary grafts were employed infrequently and radial artery grafts transiently. Overall VO volumes continued to increase 24.0% since 1996, from 470 to 583 cases with a decreased risk profile, increased mean age, and percent octogenarians and prior PCI. The percentage of mechanical valve implants decreased, while the percentage of various tissue solutions for valve disease increased. Limited access incisions and port-access were employed transiently with CAB and VO. CONCLUSIONS Coronary artery bypass volumes are decreasing, with an increasing percentage of LIMA grafts and off-pump cases. Valve operation volumes are steadily increasing, with a decreasing percentage of mechanical valve implants, in favor of various tissue solutions.

The production of malignant tumors of the lung and pleura in dogs from intratracheal asbestos instillation and cigarette smoking

Nine dogs were given yearly intratracheal instillations of crocidolite asbestos for periods up to three years. The maximum dose totalled 66 mg/kg. In addition, seven of these dogs smoked nine cigarettes per day, five days per week for six years. A malignant pleural and/or peritoneal mesothelioma developed in six of these dogs, and adenocarcinoma of the lung developed in four, one of which had areas of squamous differentiation. The first animal died of a malignant tumor six years after the onset of exposure, and the last animal died eight years after the onset.

The influence of prophylactic antibiotics on the warfarin anticoagulation response in the postoperative prosthetic cardiac valve patient. Cefamandole versus vancomycin.

The influence of cefamandole and vancomycin used for prophylaxis on the warfarin anticoagulation response in 60 cardiac valve replacement patients during the postoperative period is presented. Patients were divided into two groups, hyper-responders prothrombin time (PT) greater than or equal to 32 sec, 48 hr after the initial warfarin dose (GrIHR), or normal responders PT less than 32 sec (GrIINR). Fifteen patients (25%) were in GrIHR (PT 44.3 +/- 10.5) and 45 in GrIINR (21 +/- 5). Fourteen of the 15 GrIHR patients received cefamandole and 1 of the 15 GrIHR patients received vancomycin p less than 0.05, as prophylaxis. Warfarin sensitivity was assessed using a warfarin dose index (WDI) calculated in the initial postoperative period (WDIINT) and at discharge (WDIDIS). GrIHR patients had greater WDIINT and WDIDIS compared to GrIINR p less than 0.001. Baseline prothrombin time measured 8 hours prior to start of warfarin therapy (PTBL), was linearly correlated to the WDIINT with r = 0.8, p less than 0.001 in cefamandole patients only. The data suggests that cefamandole increases warfarin sensitivity early in the postoperative course of oral anticoagulation therapy, which may lead to excessively high prothrombin times with the possibility for serious bleeding.

Implantation Technique of Aortic Homograft Root: Emphasis on Matching the Host Root to the Graft

The technique of homograft aortic root replacement in our practice has evolved as our experience has increased. This technique is described and illustrated. In most cases, aortic annuli are reduced by using various suture techniques to match the homograft. This allows for a successful implantation of a normal-sized aortic homograft root in a patient with a diseased aortic valve and annular dilatation.

Warm Heart Surgery: A Prospective Comparison Between Normothermic and Tepid Tempurature

Due to concerns about complications from normothermic core temperature during cardiopulmonary bypass, we initiated a prospective randomized study of 200 consecutive patients. In one group (group A), both the heart and the body temperature were kept at 37°C. In the second group (group B), both the body and myocardial temperature were allowed to drift down to 34°C. There were no differences between these two groups in age, sex, preoperative numbers of elective, urgent, emergent, redo patients, or coronary artery bypass (CAB), valve, CAB/valve procedures. Their preoperative neurological, pulmonary, renal, and vascular disease status were similar. Preoperative EF was 53% in group A (100 patients) and 52.5% in group B (100 patients). Group A required more volume (p = 0.001) and had less urine output (p = 0.03) during and post bypass. Group A required more phenylephrine hydrochloride (p = 0.05) and had more difficulty managing blood pressure. Strokes and renal failure necessitating dialysis occurred more often in group A but without statistical significance. More difficulties occurred in the normothermic (37°C) group and cardioprotective effects of warm heart surgery may remain intact at 34°C. Mild “drifted/tepid” hypothermic heart surgery could be a better and safer procedure.

The comparative influence of prophylactic antibiotics on the prothrombin response to warfarin in the postoperative prosthetic cardiac valve patient: cefamandole, cefazolin, vancomycin

A prospective randomized trial was conducted comparing the effect of three antibiotics: cefamandole (CM), cefazolin (CZ), and vancomycin (V), used as prophylaxis for prosthetic valve surgery, on the prothrombin (FT) response to warfarin (W) on the third day of anticoagulant therapy. Twenty patients, with normal preoperative PTs, were randomized to each antibiotic. Their PTs were not significantly different at 2 hours after operation and the morning before W was begun. The three groups received similar W doses for 2 days, and the PT, as percentage of activity, on the morning of the third day demonstrated that V (51 ± 18%) was significantly greater (p < 0.005) than CM (29 ± 14%) or CZ (38 ± 18%). CM had a significantly greater percentage of change in PT (64 ± 14%, p < 0.0001) from the first to third day than either CZ (51.1 ± 18%) or V (44. 6 ± 19%). CM also had a greater number of patients (6) with PTs ≥ 30 seconds on day 3 than either CZ (1) or V (1). The antibiotic influence on the PT response to W in this study is ranked as CM > CZ > V.

Valve Replacement in the Geriatric Patient Using the ST. JUDE MEDICAL® Prosthesis

The results of valve replacement with the ST. JUDE MEDICAL® prosthesis in three age groups are compared. Six hundred and eighty patients underwent 735 valve replacements. Operative mortality for the entire group of patients was 6.6%. Patients were divided into three groups: Group I = < 60 years of age, Group II = 60 to 69 years and Group III = 70+ years. Operative mortality for each group was: Group I = 5%, Group II = 5% and Group III = 11.5%. Late mortality for the entire group was 7.7%. Late mortality for each group was: Group I = 5%, Group II = 7% and Group III = 12.5%. The incidence of thromboembolism and permanent major sequelae was not higher in Group III following aortic valve replacement (AVR), but was higher following mitral valve replacement (MVR). Survival at 6 years for the entire group was 86%. Six year survival for each group was: Group I = 90.5%, Group II = 88% and Group III = 77%. Operative and late mortality was markedly higher in Group III patients following these procedures: AVR + miscellaneous, MVR + coronary artery bypass (CAB) and MVR + miscellaneous. The ST. JUDE MEDICAL prosthesis is associated with satisfactory short-term and long-term results in the geriatric age group.