Hypertensive heart disease: MR tissue phase mapping reveals altered left ventricular rotation and regional myocardial long-axis velocities.

OBJECTIVES: The aim of this study was the evaluation of left ventricular (LV) segmental 3D velocities in patients with hypertensive heart disease using magnetic resonance (MR) tissue phase mapping (TPM). METHODS: LV radial, long-axis and rotational myocardial velocities were assessed by TPM in patients with LV hypertrophy and preserved EF (n = 18, age = 53 ± 12 years) and volunteers (n = 20, age = 51 ± 4 years). Systolic and diastolic peak and time-to-peak velocities were mapped onto a 16-segment LV model. 3D myocardial motion was displayed on an extended visualisation model. Correlation coefficients were calculated to investigate differences in regional dynamics. RESULTS: Patients revealed diastolic dysfunction as expressed by decreased peak long-axis velocities in all (except apical) segments (basal, P ≤ 0.01; two midventricular segments, P = 0.02, P = 0.03). During systole, hypertrophy was associated with heterogeneous behaviour for long-axis velocities including an increase in anteroseptal apical and midventricular regions (P = 0.001), a reduction in mid-inferior segments (P = 0.03) and enhanced septal velocities (P < 0.05). Segmental correlation analysis revealed altered dynamics of LV base rotation and increased dyssynchrony of lateral long-axis motion. CONCLUSIONS: Patients with hypertensive heart disease demonstrated alterations in systolic long-axis motion, basal rotation and dyssynchrony. Longitudinal studies are needed to investigate the value of regional wall motion abnormalities regarding disease progression and outcome.

Magnetic resonance tissue phase mapping: analysis of age-related and pathologically altered left ventricular radial and long-axis dyssynchrony.

PURPOSE: To employ magnetic resonance tissue phase mapping (TPM) for the assessment of age-related left ventricular (LV) synchrony of radial and long-axis motion in healthy volunteers and in hypertensive heart disease, dilated cardiomyopathy (DCM), and left bundle branch block (LBBB). MATERIALS AND METHODS: TPM (spatial/temporal resolution = 1.3 × 2.6 mm(2)/13.8 msec) was employed to measure radial and long-axis myocardial velocities in 58 healthy volunteers of three age groups and 37 patients (hypertensive, n = 18; DCM, n = 12; DCM and LBBB n = 7). Regional times-to-peak velocities (TTP) in systole and diastole were derived for all LV segments. Four measures of dyssynchrony were defined as the standard deviation of systolic and diastolic TTP for radial and long-axis motion. RESULTS: Systolic radial and diastolic long-axis dyssynchrony was increased (P < 0.01) in all patient groups compared to controls. Multiple regressions revealed a significant relationship of dyssynchrony with LV ejection fraction and mass for systolic radial (P < 0.001 resp. P = 0.02), diastolic radial (P < 0.001 resp. P < 0.05), and long-axis (P < 0.001 resp. P = 0.001) motion. Diastolic dyssynchrony correlated with the LV remodeling index (P < 0.05) and increased with age (P < 0.03). Systolic long-axis dyssynchrony was not influenced by disease or LV function. CONCLUSION: Radial systolic and long-axis diastolic dyssynchrony were the most sensitive markers for altered dyssynchrony in hypertensive heart disease or DCM. Future studies are needed to evaluate the diagnostic value of TPM-derived dyssynchrony parameters.

CarboMedics Mitroflow pericardial aortic bioprosthesis - performance in patients aged 60 years and older after 15 years.

BACKGROUND: The purpose of this study was to carry out a current assessment of the Mitroflow pericardial bioprosthesis (model 11) according to the durability of the prosthesis after 15 years in patients aged 60 years or older. METHODS: This bioprosthesis was implanted in 161 patients (mean age 69.5 +/- 6.3 years; range 60 - 94 years) undergoing aortic valve replacement (AVR) between 1982 and 1992. There were 84 patients aged 60 - 69 years (mean 64.5 +/- 3.1years) and 77 patients aged 70 years or older (mean 74.8 +/- 4.3 years). Of the total population, concomitant procedures were performed in 63 patients (39.1 %); of these, coronary artery bypass grafting was performed in 39 (24.2 %). RESULTS: Early mortality was 4.8 % (4 patients) in the 60 - 69 year age group and 10.4 % (8) in patients aged 70 years or older ( P = 0.290). Late mortality was 4.5 %/patient-year (35) for those aged 60 - 69 years and 8.1 %/patient-year (49) for those aged 70 years or older ( P = 0.007). Patient survival at 15 years of patients aged 60 - 69 years was 47.6 +/- 6.3 % and of patients aged 70 years or older was 20.9 +/- 5.4 % ( P = 0.003) ( ). Freedom from valve-related mortality for patients in the 60 - 69 year age group was 92.1 +/- 3.5 % at 15 years (0.6 %/patient-year [5]), and in the patient group aged 70 years or older it was 84.4 +/- 5.3 % (1.3 %/patient-year [8]; P = 0.194). Freedom from reoperation for patients in the 60 - 69 year age group was 73.9 +/- 5.0 % (2.6 %/patient-year [20]), and for patients aged 70 years or older it was 91.4 +/- 3.4 % (1.0 %/patient-year [6]; P = 0.029). The structural valve deterioration (SVD) rate for patients in the 60 - 69 year age group was 2.4 %/patient-year (19), and for patients aged 70 years or older it was 1.0 %/patient-year (6) ( P = 0.041). Actuarial freedom from structural valve deterioration at 15 years for patients aged 60 - 69 years was 62.0 +/- 7.3 %, and 80.8 +/- 7.9 % for patients aged 70 years and older ( P = 0.049) (actual freedom 73.9 +/- 5.2 % and 91.4 +/- 3.4 %, respectively). CONCLUSIONS: The Mitroflow pericardial bioprosthesis can still be recommended for aortic valve replacement in patients 70 years and older.

Performance of bioprostheses and mechanical prostheses assessed by composites of valve-related complications to 15 years after aortic valve replacement.

OBJECTIVE: This study was conducted to compare the composites of valve-related complications, namely reoperation, morbidity (defined as permanent neurologic or other functional impairment), and mortality, between bioprostheses and mechanical prostheses for aortic valve replacement. METHODS: Between 1982 and 1998, 2195 bioprostheses were implanted in 2179 patients and 980 mechanical prostheses were implanted in 883 patients. Total follow-up was 16,442 years and 5740 years for bioprostheses and mechanical prostheses, respectively. Eight variables were considered as predictors of risk for the composites of valve-related complications. RESULTS: Linearized rates for valve-related reoperation were 1.3%/patient-year and 0.3%/patient-year for bioprostheses and mechanical prostheses (P < .001), respectively. All age groups were differentiated, except >70 years. Valve-related morbidity was differentiated for all age groups and overall, for bioprostheses and mechanical protheses, was 0.4 %/patient-year and 2.1%/patient-year, respectively (P < .001). Overall valve-related mortality was 1.0%/patient-year for bioprostheses and 0.7%/patient-year for mechanical prostheses (P = .018). Age and valve-type were predictive risk factors for reoperation and morbidity, whereas age alone was predictive of mortality. Actual freedom from valve-related reoperation favored mechanical prostheses for all age groups, except 61-70 years and >70 years. Actual freedom from valve-related morbidity favored bioprostheses in all age groups, except < or =40 years. Actual freedom from valve-related mortality was undifferentiated in patients 51-60, 61-70, and >70 years. CONCLUSION: No differences were observed in valve-related reoperation and mortality in patients >60 years. Comparative evaluation gives high priority for bioprostheses in patients >60 years based on improved morbidity profile. This evaluation extends this center's recommendation for bioprostheses in aortic valve replacement to include patients >60 years.

Elderly valve replacement with bioprostheses and mechanical prostheses. Comparison by composites of complications.

AIM: The goal of aortic valve replacement (AVR) surgery in the elderly (= or >75 years) is to extend survival and minimize valve-related morbidity, mortality and reoperation. As the elderly population lives longer, those with implanted valves are at risk of suffering valve related complications. We hypothesize that bioprostheses are appropriate for the elderly. METHODS: The follow-up evaluation of 966 patients with valves (AVR, 666; mitral valve replacements [MVR], 226; multiple valve replacements [MR], 74) implanted between 1975 and 1999 was examined. There were 879 bioprotheses (BP) and 87 mechanical prostheses (MP). The mean age was 78.9+/-3.3 years (range 75-94.6 years). Concomitant coronary artery bypass was performed in AVR in 51.7%, MVR in 50.4% and MR in 28.4%. Valve type, valve lesion, coronary artery bypass (previous/concomitant), age and gender were considered as independent predictors of composites and survival. The total follow-up was 3905 patient-years. RESULTS: Early mortality was for AVR 9.6% (64), MVR 15.0% (34) and MR 25.7% (19). The late mortality was for AVR 8.8%, MVR 10.4% and MR 8.8%/patient-year. The only independent predictor of survival and valve-related mortality, morbidity and reoperation was age for survival in those with AVR, hazard ratio 1.15 [CL 1.03-1.27] p=0.0094). The BP reoperative rate was 0.5%/patient-year (reoperation was fatal in 6/15) of total, MP reoperative rate was 0% [reasons for reoperation structural valve deterioration (4), non-structural dysfunction (6), prosthetic valve endocarditis (5), reoperation fatality due to non-structural dysfunction (2), prosthetic valve endocarditis (4)]. Overall patient survival at 10 and 15 years, respectively, was 30.5+/-2.4% and 3.6+/-2.2% irrespective of valve position and type. Overall actual and actuarial freedom from valve-related morbidity at 15 years was 96.8+/-0.9% and 93.7+/-2.3%, respectively. Actual and actuarial overall freedom from valve-related mortality at 15 years was 84.3+/-2.4% and 58.4+/-0.9%, respectively. Overall actual and actuarial freedom from valve related reoperation at 15 years was 95.8+/-1.6% and 74.8+/-16.9%, respectively. CONCLUSIONS: BP valves are further confirmed to be a good option for AVR in patients = or >75 years of age.

Valve replacement surgery complicated by acute renal failure--predictors of early mortality.

BACKGROUND: Acute renal failure (ARF) is a serious complication of valve replacement surgery. The aim of this study was to determine the predictors of early mortality and if causative factors are preventable. METHODS: In the 25-year period between 1977 and 2002, 255 (2.6%) of 9721 patients (11,007 operations), who had valve replacement surgery, were managed for ARF with dialysis. The mean age of the patient population was 67.1 +/- 11.6 years (range 24 to 87 years, median 70.3 years). Fifty preoperative, operative, and postoperative risk factors were assessed as predictors of early mortality by univariate and multivariate modeling. RESULTS: The early mortality was 25.1% (64 patients). The predictors by univariate analysis were: New York Heart Association class (p = 0.001); ASA within 5 days (p = 0.030); cardiogenic shock (p = 0.010); infection--perioperative sepsis and preoperative endocarditis (p = 0.000); intraoperative stroke (p = 0.003); status--emergent (p = 0.000); mitral valve replacement (p = 0.040); ischemic (X-clamp) time >120 minutes (p = 0.020); cardiopulmonary bypass time >180 minutes (p = 0.000); surgical time >360 minutes (p = 0.000); surgical hemorrhage (p = 0.020); acute respiratory distress syndrome (ARDS) (p = 0.040). Multivariate predictors were urgent status of operation, odds ratio (OR) 0.3 (p = 0.029); emergent status of operation, OR 5.8 (p = 0.034); ischemic (X-clamp) time >120 minutes, OR 4.4 (p = 0.030); surgical time >360 minutes, OR 6.3 (p = 0.019); surgical hemorrhage, OR 5.1 (p = 0.003); perioperative nosocomial sepsis, OR 3.8 (p = 0.006); and preoperative endocarditis, OR 4.4 (p = 0.004). CONCLUSIONS: Early mortality from ARF in valve replacement surgery is related to emergent status, ischemic and surgical times, surgical hemorrhage, and nosocomial infection/preoperative endocarditis. Among the variables assessed, preoperative renal insufficiency, unstable angina/recent myocardial infarction <6 weeks, and concomitant coronary artery bypass were not predictive. The evaluation of predictors of ARF requires further extensive assessment.

Bioprostheses with atrial fibrillation and mechanical prostheses in aortic valve replacement.

BACKGROUND: Clinical performance of bioprostheses (BP) with presence of atrial fibrillation and/or paced rhythm and mechanical prostheses (MP) in aortic valve replacement was considered a study of importance. METHODS: Aortic valve replacement (AVR) was performed in 163 replacements with porcine bioprostheses (Carpentier-Edwards supra-annular) with atrial fibrillation/paced rhythm identified at latest follow-up. Mechanical population was 886 procedures (St. Jude Medical = 436; CarboMedics = 450). Concomitant coronary artery bypass (CAB) was conducted in 40.5 % (66) of BP; 27.0 % (239) of MP. MP patients were all (100 %) on Coumadin and BP patients 35.6 % on acetylsalicylic acid (ASA), 37.4 % Coumadin, 7.4 % Coumadin + ASA, and 19.6 % on no therapy. RESULTS: Major thromboembolism (TE) and hemorrhage (ATH) occurred in 2.4 %/pt-yr (32) for BP and 5.3 %/pt-yr (157) for MP ( p < 0.0001); (TE major 1.6 %/pt-yr [21] for BP and 2.1 %/pt-yr [62] for MP [ p = 0.24]; ATH = 0.8 %/pt-yr [11] for BP and 3.2 %/pt-yr [95] for MP) ( p < 0.0001). There were no predictors of overall TE, TE major, ATH, overall TE + ATH, and TE major + ATH. Age and CAB were predictors of survival. Overall BP survival at 8 years was 97.5 +/- 1.5 %; and for MP 66.4 +/- 4.8 % ( p < 0.01). Actuarial freedom from overall thromboembolism and hemorrhage was 54.5 +/- 10.8 % for MP; 85.9 +/- 3.1 % for BP ( p = 0.0000). For major thromboembolism and hemorrhage, actuarial freedom was 63.4 +/- 11.8 % for MP; 91.4 +/- 2.5 % for BP ( p = 0.0003). CONCLUSIONS: Patients with atrial fibrillation/paced rhythm having AVR with bioprostheses with 45 % on Coumadin have greater freedom from thromboembolism and hemorrhage than after AVR with mechanical prostheses on Coumadin.

Performance of bioprostheses and mechanical prostheses assessed by composites of valve-related complications to 15 years after mitral valve replacement.

OBJECTIVE: Predominant concerns of patients undergoing valve replacement surgery are risks of death, stroke, antithrombotic bleeding, and reoperation related to the replacement prosthesis. The purpose of this study was to compare valve-related reoperation, morbidity (permanent impairment), and mortality between bioprostheses and mechanical prostheses for mitral valve replacement. METHODS: Between 1982 and 1998, a total of 959 bioprostheses were implanted in 943 patients, and a total of 961 mechanical prostheses were implanted in 839 patients. Total follow-ups were 5730 years for bioprostheses and 5271 years for mechanical prostheses. Eight variables were considered as predictors of risk for the composites of valve-related complications. RESULTS: The linearized occurrence rates for valve-related reoperation were 3.7 events/100 patient-years for bioprostheses and 0.5 events/100 patient-years for mechanical prostheses ( P < .001), with all age groups differentiated except older than 70 years. Valve-related morbidity was undifferentiated for bioprostheses and mechanical prostheses. Valve-related mortalities were 1.7 events/100 patient-years for bioprostheses and 0.7 events/100 patient-years for mechanical prostheses ( P < .001). Predictors of valve-related reoperation were age and valve type. The only predictor of valve-related morbidity was age, whereas age and valve type were predictors for valve-related mortality. Actual freedom from valve-related reoperation favored mechanical prostheses in all age groups except older than 70 years (91.7% +/- 2.0% for bioprostheses at 15 years and 96.7% +/- 1.5% at 12 years for mechanical prostheses). Actual freedom from valve-related morbidity was not different between bioprostheses and mechanical prostheses. Actual freedom from valve-related mortality favored mechanical prostheses in all groups except older than 70 years. CONCLUSION: Comparative evaluation gives high priority in mitral valve replacement for mechanical prostheses relative to bioprostheses for freedom from valve-related reoperation and valve-related mortality but not valve-related morbidity. Freedom from valve-related reoperation and valve-related mortality favors mechanical prostheses for all age groups except older than 70 years. Valve-related morbidity, due to neurologic or functional impairments, does not differentiate between bioprostheses and mechanical prostheses.

Surgical management of acute sigmoid diverticulitis.

PURPOSE: To determine the frequency of use of resection and primary anastomosis in the management of acute sigmoid diverticulitis at Royal Columbian Hospital. METHODS: A retrospective chart review of all patients undergoing emergency surgery for acute sigmoid diverticulitis between 1989 and 2000 at the Royal Columbian Hospital, New Westminster, BC, was carried out in order to determine the frequency of resection and primary anastomosis. Patients who underwent bowel preparation were excluded. RESULTS: Ninety-seven cases met the criteria. There were 33 cases of resection and primary anastomosis (34%). Five of these cases were protected with a proximal diverting stoma giving an incidence of 85% unprotected primary anastomosis in a group of patients undergoing emergency surgery for acute sigmoid diverticulitis. There was 1 anastomotic leak, 7 wound infections, and 3 deaths with an average length of stay of 9 days. CONCLUSIONS: The practice of resection and primary anastomosis for acute sigmoid diverticulitis at the Royal Columbian Hospital has an acceptable morbidity and mortality.

Carpentier-Edwards supraannular porcine bioprosthesis: second-generation prosthesis in aortic valve replacement.

BACKGROUND: The Carpentier-Edwards supraannular porcine bioprosthesis experience for more than 18 years has been evaluated by actuarial and actual analysis to determine the clinical performance in aortic valve replacement. METHODS: From 1981 to 1998, 1,823 patients (mean age 68.5 years, range 20 to 90 years) underwent 1,846 procedures. Previous coronary artery bypass was performed in 3.1% (56) and previous valve repair/replacement in 6.0% (110). Concomitant coronary artery bypass grafting was performed in 41.5% (756). RESULTS: The overall valve-related complication rate was 4.5%/patient-year (567 patients) with a fatality rate of 0.9%/patient-year (110 patients). The patient survival, at 15 years, was 33.0%+/-3.7% for the 61 to 70 years age group and 13.5%+/-2.4% for the older than 70 years group. At 15 years, the overall actual, cumulative freedom from reoperation was 83.2%+/-1.4%, valve-related mortality was 88.0%+/-1.2%, and valve-related residual morbidity was 92.0%+/-0.8%. The actual freedom from structural valve deterioration at 15 years was 84.2%+/-2.8% for the 61 to 70 years group and 97.1%+/-0.9% for the older than 70 years group. CONCLUSIONS: The Carpentier-Edwards porcine bioprosthesis provides excellent freedom from structural valve deterioration, and overall freedom from valve-related morbidity, mortality, and reoperation for aortic valve replacement for up to 15 years. The prosthesis is recommended for patients older than 70 years and for patients 61 to 70 years, especially when extended survival is not anticipated.

CarboMedics mechanical prosthesis: performance at eight years.

BACKGROUND AND AIM OF THE STUDY: The bileaflet St. Jude Medical mechanical prosthesis has been implanted for over 20 years. The purpose of this study was to evaluate the clinical performance of the bileaflet CarboMedics (CM) prosthesis, which was introduced in 1986. METHODS: The CM prosthesis was implanted in 1,258 patients (709 males, 549 females; mean age 60.9 +/- 12.3 years) between 1989 and 1997. The prosthesis distribution was aortic valve replacement (AVR) 613; mitral valve replacement (MVR) 447; and multiple replacement (MR) 231. Coronary artery bypass (CAB) was performed in 334 (26.6%) patients; previous procedures had been performed in 346 (27.5%). The age distribution was <60 years (n = 527), 61-70 years (n = 424) and >70 years (n = 307). Risk factors assessed were age or age groups, gender, CAB, previous surgery, rhythm, valve position, status and NYHA functional class. The total follow up was 4,765.0 patient-years (pt-yr), and was 98.4% complete. RESULTS: The early mortality rate was 5.6% (AVR 4.8%, MVR 3.7%, MR 11.5%). The late mortality rate was 3.7%/pt-yr (n = 174), and valve-related mortality 1.1%/pt-yr (n = 50). The total thromboembolism (TE) rate was 4.1%/pt-yr (n = 195) (p = NS by valve position); the major TE rate was 1.9%/pt-yr and fatal TE rate 0.31%/pt-yr (n = 15). The valve thrombosis rate was 0.31%/pt-yr (n = 15; 11 MVR, four MR). The fatal thrombosis rate was 0.06%/pt-yr (n = 3; two MVR, one MR). The hemorrhage rate was 2.7%/pt-yr (n = 128) and fatal hemorrhage rate 0.4%/pt-yr (n = 20). The reoperation rate was 1.0%/pt-yr (n = 46), fatal 0.1%/pt-yr (n = 5). The actuarial freedom from overall TE at eight years was 77.3 +/- 2.8%; major TE 88.5 +/- 1.6%, and hemorrhage 76.4 +/- 3.2% (all p = NS by valve position). There were no independent predictors of overall TE and TE exclusion of early events. The only predictor for TE major was status (emergency > urgent > elective). The actuarial freedom from valve-related mortality at eight years was 91.4 +/- 1.8% (p = NS by position) (actual freedom 93.0 +/- 1.3%). The actuarial freedom from valve-related reoperation was 91.1 +/- 2.4% (p <0.05; AVR > MVR and MR, MVR > MR) (actual freedom 92.2 +/- 2.7%). Overall survival rate at eight years was 68.2 +/- 2.3% (p <0.05; AVR > MVR and MR, MVR > MR). CONCLUSION: The clinical performance of the CarboMedics mechanical prosthesis is satisfactory when implanted in the mitral, aortic and multiple positions.

Actuarial versus actual freedom from structural valve deterioration with the Carpentier-Edwards porcine bioprostheses.

BACKGROUND: The clinical performance of porcine bioprostheses for valve replacement surgery has been evaluated for over three decades by actuarial analysis as the standard for reporting time-related results. The incidence of structural valve deterioration (SVD) is used for the selection of prostheses for various subsets of patients. Actual or cumulative incidence analysis may provide a superior method to determine durability of bioprostheses. OBJECTIVE: To compare actuarial versus actual methodology in determining the durability of porcine bioprostheses for aortic (AVR) and mitral valve replacement (MVR). PATIENTS AND METHODS: Carpentier-Edwards porcine bioprostheses were implanted between 1975 and 1995 in 2237 AVR and 1582 MVR. The mean age for AVR patients was 65.4+/-12 years and for MVR patients 61.7+/-12 years. The cumulative follow-up for AVR was 14,810 years (mean 6.6+/-4.7) and for MVR 9718 years (mean 6. 1+/-4.5). RESULTS: For AVR the actual freedom from SVD was 87.4+/-2. 0% and 95.6+/-1.8% in those aged 61 to 70 years and more than 70 years, respectively; the actuarial freedom was 75.9+/-4.2% and 82. 3+/-7.9%, respectively. For MVR the actual freedom from SVD was 69. 4+/-2.5% and 92.9+/-1.9% for those aged 61 to 70 years and more than 70 years, respectively; the actuarial freedom was 25.5+/-5.7% and 79. 5+/-6.0%, respectively. Predictors of freedom from SVD for AVR were identified as advancing age, falling into the age groups 61 to 70 and those older than 70 years, and intermediate valve sizes; predictors for MVR were advancing age and age older than 70 years. CONCLUSIONS: Comparison of methods of durability assessment revealed that actual freedom from SVD supports porcine bioprostheses for AVR in patients more than 60 years of age and for MVR in patients more than 70 years of age. This evaluation with experience to 15 years supports the indications for use of porcine bioprostheses.

Bileaflet mechanical prostheses performance in mitral position.

OBJECTIVE: The experience with the Carbomedics (CM) and the St. Jude Medical (SJM) bileaflet mechanical prostheses was evaluated to determine thromboembolic and hemorrhagic complications and predictive risk factors. METHODS: From 1989 to 1994, a total of 625 patients had mitral valve replacement (CM, 240; SJM, 385); 32.5% (203), concomitant procedures and 32.8% (205), previous cardiac surgery, primarily valve replacement procedures. RESULTS: The pre-operative variables did not distinguish the populations, except for previous surgery CM 37.9% and SJM 29.6% (P < 0.05). The pre-operative variables (type of prostheses, cardiac rhythm, coronary artery bypass, NYHA III/IV, advancing age, gender, urgency status and previous surgery) were not predictive of overall thromboembolism (TE), major TE, minor TE, prosthesis thrombosis and hemorrhage (P not significant; P = NS). The linearized rate of total TE events for overall MVR was 5.0%/patient-year (CM 4.4; SJM 5.4). The < or = 30 day major crude rate was 0.44%, while the > 30 day late major event rate was 2.0%/patient-year. Of the total TE events 91% of < or = 30 days and 75%, > 30 days had an INR < 2.5 at or immediately prior to the event. The thrombosis rate (included in TE events) was 0.63%/patient-year (ten events, four managed successfully with thrombolysis, five successfully with reoperation, and one fatality identified at autopsy). The freedom, at 5 years, from major/fatal TE, thrombosis and hemorrhage from anticoagulation was 88.2%, and 89.5% exclusive of early events. CONCLUSIONS: This non-randomized prospective observational evaluation of the CarboMedics and St. Jude Medical prostheses has not revealed any differentiation in performance of the prostheses. The study serves as a single institution experience with the potential for future comparative evaluation.

Bileaflet mechanical prostheses for aortic valve replacement in patients younger than 65 years and 65 years of age or older: major thromboembolic and hemorrhagic complications.

OBJECTIVE: To determine major thromboembolic and hemorrhagic complications and predictive risk factors associated with aortic valve replacement (AVR), using bileaflet mechanical prostheses (CarboMedics and St. Jude Medical). DESIGN: A case series. SETTING: Cardiac surgical services at the teaching institutions of the University of British Columbia. PATIENTS AND METHODS: Patients 2 age groups who had undergone AVR between 1989 and 1994 were studied. Group 1 comprised 384 patients younger than 65 years. Group 2 comprised 215 patients 65 years of age and older. RESULTS: The linearized rates of major thromboembolism (TE) occurring after AVR were 1.54%/patient-year for group 1 and 3.32%/patient-year for group 2; the rates for major TE occurring more than 30 days after AVR were 1.13%/patient-year for group 1 and 1.55%/patient-year for group 2. The crude rates for major TE occurring within 30 days of AVR were 1.04% for group 1 and 3.72% for group 2. The death rate from major TE in group 1 was 0.31%/patient-year and in group 2 was 0.88%/patient-year. Of the major TE events occurring within 30 days, 100% of patients in both age groups were inadequately anticoagulated at the time of the event, and for events occurring more than 30 days after AVR, 45% in group 1 and 57% in group 2 were inadequately anticoagulated (INR less than 2.0). The overall linearized rates of major hemorrhage were 1.54%/patient-year for group 1 and 2.21%/patient-year for group 2. There were no cases of prosthesis thrombosis in either group. The mean (and standard error) overall freedom from major TE for group 1 patients at 5 years was 95.6% (1.4%) and with exclusion of early events was 96.7% (1.3%); for group 2 patients the rates were 90.0% (3.2%) and 93.7% (3.0%), respectively. The mean (and SE) overall freedom from major and fatal TE and hemorrhage for group 1 patients was 90.1% (2.3%) and with exclusion of early events was 91.2% (2.3%); for group 2 patients the rates were 87.9% (3.1%) and 92.5% (2.9%), respectively. The 5-year rate for freedom from valve-related death for group 1 patients was 96.3% (2.1%) and for group 2 patients was 97.2% (1.2%). CONCLUSION: The thromboembolic and hemorrhagic complications after AVR with bileaflet mechanical prostheses occur more frequently and result in more deaths in patients 65 years of age and older than in patients years younger than 65 years.

Mitroflow pericardial bioprosthesis experience in aortic valve replacement > or =60 years of age.

BACKGROUND: The Mitroflow pericardial bioprosthesis (model 11), a second-generation pericardial prosthesis, has clinical performance assessment to 10 years. The authors previously recommended the prosthesis for aortic valve replacement in patients 70 years or older. The purpose of the current assessment is to report on performance in patients 60 years or older undergoing aortic valve replacement. METHODS: This bioprosthesis was implanted in 161 patients (mean age, 69.5+/-6.3 years; range, 60 to 94 years) with aortic valve replacement from 1982 to 1992. There were 84 patients 60 to 69 years (mean, 64.5+/-3.1 years) and 77 patients 70 years or older (mean, 74.8+/-4.3 years). Of the total population, concomitant procedures were performed in 63 patients (39.1%); of these, coronary artery bypass grafting was performed in 39 (24.2%). RESULTS: The early mortality was 4.8% (4 patients) for the 60 to 69-year age group and 10.4% (8) for those 70 years or older (not significant). The late mortality was 4.4%/patient-year (27) for those 60 to 69 years and 6.9%/ patient-year (35) for those 70 years or older (not significant). The patient survival for those 60 to 69 years was 58.0%+/-6.3% and for those 70 years or older, 45.3%+/-5.9% at 10 years (p < 0.05). The valve-related mortality for those 60 to 69 years was 0.82%/patient-year (5) and for those 70 years or older, 1.58%/patient-year (8) (not significant). The reoperation rate for those 60 to 69 years was 3.29%/patient-year (20) and for those 70 years or older, 1.0%/patient-year (5) (p < 0.05). The structural valve deterioration rate for those 60 to 69 years was 3.13%/ patient-year (19) and for those 70 years or older, 1.2%/ patient-year (6) (p < 0.05). CONCLUSIONS: The Mitroflow pericardial bioprosthesis remains recommended for aortic valve replacement in patients 70 years and older.

Influence of coronary artery bypass and age on clinical performance after aortic and mitral valve replacement with biological and mechanical prostheses.

The influence of prosthetic type, age, and coronary artery bypass grafting (CABG) on valve-related complications by valve position was evaluated in a population of 2353 bioprosthesis patients (mean age, 66.5 years; range, 13 to 89 years) and in a population of 1112 mechanical prosthesis patients (mean age, 59.1 years; range, 13 to 91 years). The follow-up was complete to 96% and 98%, respectively, for the bioprosthesis and mechanical prosthesis groups. The patient groups were evaluated by actuarial assessment of survival and valve complications and composites. Preoperative factors were evaluated for determination of significant independent predictors by multivariate proportional-hazard regression analysis. CABG was an influential factor in the actuarial analysis. Survival was superior for aortic mechanical replacements without CABG and for mitral replacements, both biological and mechanical, without CABG (P < .05). The freedom from thromboembolism (TE) and antithromboembolic hemorrhage (ATH) was greater for biological prostheses with and without CABG for aortic replacements (P < .05) but not for mitral replacements (P = NS). The freedom from valve-related mortality was not influenced by CABG for either position (P = NS). The freedom from valve-related reoperation was greater for biological prostheses with CABG than without CABG for both aortic and mitral replacements (P < .05). The evaluation of covariates as independent predictors revealed CABG to be a nonpredictor for aortic valve replacement (AVR) (P = NS) but a predictor of survival and valve-related reoperation for mitral valve replacement (MVR) (P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Unilateral versus bilateral internal mammary revascularization. Survival and event-free performance.

BACKGROUND: The influence of unilateral (UL) and bilateral (BL) mammary artery revascularization, within age groups < or = 60 years and > 60 years, on patient survival, ischemic-related events, and interventional management was studied in 1142 patients who had coronary artery bypass graft surgery between 1984 and 1992. METHODS AND RESULTS: UL revascularization was performed in 765 (67%) and BL in 377 (33%) patients with supplemental vein grafts. The overall early and hospital mortality rate was 2.7%. For UL in the age group < or = 60 years, it was 1.1%; for BL < or = 60 years, 1.3% (P = NS); for UL > 60 years, 4.3%; and for BL > 60 years, 2.8% (P = NS). Twenty-five preoperative patient characteristics representing demographics, extent of disease, concomitant disease, ventricular dysfunction, previous surgery, and status did not differentiate the patient groups (P = NS). Patient survival at 5 years was not different: 94% for UL < or = 60 years, 95% for BL < or = 60 years, 91% for UL > 60 years, and 86% for BL > 60 years (P = NS). The freedom from ischemic-related events was not different at 5 years (P = NS). The freedom from recurrent angina was 78% for UL < or = 60 years, 88% for BL < or = 60 years, 82% for UL > 60 years, and 83% for BL > 60 years (P = NS). The myocardial infarction freedom was 98% for UL < or = 60 years, 96% for BL < or = 60 years, 99% for UL > 60 years, and 97% for BL > 60 years (P = NS). The freedom from sudden unexpected death and cardiac death did not differentiate the groups (P = NS). The freedom from angioplasty and reoperation did not differentiate the groups (P = NS). The freedom from all ischemic-related and interventional events was 76% for UL < or = 60 years, 84% for BL < or = 60 years, 81% for UL > 60 years, and 79% for BL > 60 years (P = NS). A trend exists for less angina pectoris in the bilateral population < or = 60 years, which reflects in the trend in the freedom from overall events. CONCLUSIONS: UL and BL mammary artery revascularizations have the same early mortality regardless of age but do not reveal any advantage for BL revascularization at 5 to 7 years.

An evaluation of prognostic scoring systems in patients with follicular thyroid cancer.

BACKGROUND: Prognostic scoring systems for thyroid cancer have not been investigated in patients with pure follicular cancer; thus, the purpose of this study was to compare the following prognostic indices: the European Organization for Research and Treatment of Cancer (EORTC) method; the Age, Grade, Extent, Size (AGES) score; and the Age, Metastasis, Extent, Size (ALIES) score. PATIENTS AND METHODS: A retrospective study reviewing 122 patients actively treated between 1955 and 1990 was conducted. Scoring systems were calculated and survival analysis completed. AGES low-risk patients were analyzed with respect to known risk factors. RESULTS: The AGES scoring system significantly defined low- and high-risk groups (P = 0.0041); the ratio of deaths between high-versus low-risk groups was 1.9:1. EORTC scores distinguished four risk groups (P = 0.002). The AMES scoring system did not significantly assign risk. In multivariate analysis of low-risk AGES patients, age, perithyroidal tissue involvement, and positive frozen section reached statistical significance. CONCLUSIONS: The AGES and EORTC scoring systems best defined low- and high-risk groups of patients with pure follicular cancer, although the separation between groups was low.

Cultured epithelial autograft: five years of clinical experience with twenty-eight patients.

Cultured epithelial autograft (CEA) has been used as an adjunct in burn wound coverage at the Vancouver Hospital and Health Sciences Centre since 1988, and has been available to all patients admitted with significant burn injuries. During the 5-year period from 1988 to 1992 inclusive, 28 patients treated with CEA survived long enough for assessment. The mean age was 35.3 years with a mean total body surface area burn of 52.2% and a mean total full thickness injury of 42.4%. CEA was applied to wounds covering between 2% and 35% body surface area (BSA; mean 10.4%) after excision to fat or fascia. Most wounds had interim homograft coverage. Preservation of homograft dermis was attempted in three patients at the time of removal without effect. The mean CEA "take" was 26.9% of the grafted area. Eight patients had 50% or greater take and were discharged with between 1 and 19% BSA covered with CEA. Thirteen patients had no take on wounds between 2 and 16% BSA. Overall mortality in burn patients treated at the Vancouver Hospital and Health Sciences Centre from 1988 to 1992 was not significantly different from 1983 to 1987 with the populations being similar in terms of total BSA burns, age, inhalation injury, and homograft availability. When compared to a matched control population from the preceding 5 years, when CEA was not available, there was no significant difference in duration of hospital stay or number of autograft harvests. However, approximately one more debridement without autograft harvest per CEA patient occurred. Timing and depth of wound excision, interim coverage, type of dressing, and wound microbiology were not found to influence good versus poor take. The anterior trunk and thighs were the best recipient sites. Subjective differences between CEA and meshed autograft were noted. The results show that after 5 years of use, CEA engraftment continues to be unpredictable and inconsistent, and hence, it should be used as only a biologic dressing and experimental adjunct to conventional burn wound coverage with split thickness autograft.

Porcine bioprostheses in the elderly: clinical performance by age groups and valve positions.

Porcine bioprostheses have been recommended and used for cardiac valve replacement in the elderly. A review of 1,984 patients with 2,042 operations, performed between 1975 and 1992, has afforded a detailed evaluation of clinical performance by valve positions and age groups within the elderly population. The numbers of operations performed by age groups were 65 to 69 years, 719; 70 to 74 years, 745; 75 to 79 years, 431; 80 to 84 years, 119; and 85 years or older, 28. The early mortality rate overall was 9.5% (195 patients), range 6.9% to 17.8% by age groups (p < 0.05), and 11.9% with concomitant procedures and 7.6% without (p < 0.05). The total cumulative follow-up was 10,060 patient-years (mean, 4.9 years). The late mortality rate was 7.0%/patient-year (for age groups, 5.8% to 13.4%/patient-year) (p = not significant). The patient survival at 15 years ranged from 25% +/- 4% for 65 to 69 years to 9% +/- 5% for 75 to 79 years (p < 0.05). The freedom from valve-related complications and composites at 10 years revealed differences (p < 0.05) by age groups only for structural valve deterioration: 85% +/- 2% for 65 to 69 years versus 98% +/- 2% for 80 to 84 years. The overall freedom from structural valve deterioration at 10 years for aortic valve replacement was 98% +/- 1%; for mitral valve replacement, 79% +/- 3%; and for multiple replacement, 86% +/- 7% (p < 0.05, aortic valve replacement > mitral valve replacement).(ABSTRACT TRUNCATED AT 250 WORDS)