Robert T. Miyagishima
University of British Columbia
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The Annals of Thoracic Surgery | 1988
W. R. E. Jamieson; L.J. Rosado; A. I. Munro; Alfred N. Gerein; Lawrence H. Burr; Robert T. Miyagishima; Michael T. Janusz; G.F.O. Tyers
Primary tissue failure (structural valve deterioration) has been documented as the most prominent complication of porcine bioprostheses. The influence of age on primary tissue failure has received limited consideration. From 1975 to 1986, 1,301 Carpentier-Edwards standard porcine bioprostheses were implanted in 1,183 patients in 1,201 operations. Of the total number of prostheses, 97.7% were implanted prior to 1983. The mean follow-up was 5.6 years and was 97.5% complete. Primary tissue failure was identified in 96 patients (98 operations) at reoperation (95) or autopsy (3). One hundred four (104) prostheses were involved. Thirty-one failed after aortic valve replacement (AVR), 49 after mitral valve replacement (MVR), and 24 after multiple-valve replacement (18 patients). There were 47 male and 49 female patients. The mean age at implantation was 47 years (range, 8 to 72 years). The mean implantation time was 74.0 months. The freedom from primary tissue failure at 10 years is 77.0 +/- 2.9% overall; for AVR, 83.1 +/- 3.7%; for MVR, 72.1 +/- 4.9%; and for multiple-valve replacement, 65.5 +/- 7.8%. The freedom from deterioration for patients less than 20 years of age is significantly less than that for other age groups. The freedom from deterioration increased by decades; the greatest freedom was noted in patients 70 to 80 years old and 80 years old or older. The freedom from deterioration at 10 years for patients less than 30 years of age is 26.8 +/- 17.2%; 30 to 59 years, 77.4 +/- 3.0%; and 60 years and older, 83.1 +/- 4.2%.(ABSTRACT TRUNCATED AT 250 WORDS)
The Annals of Thoracic Surgery | 1998
W.R. Eric Jamieson; Lawrence H. Burr; A. Ian Munro; Robert T. Miyagishima
BACKGROUND The Carpentier-Edwards standard porcine bioprosthesis experience to 21 years has been evaluated to determine the influence of structural valve deterioration by valve position in various age groupings. METHODS From 1975 to 1988, 1,181 patients had the prosthesis implanted in 1,198 procedures. The mean age of the population was 57.9+/-12.5 years (range, 21 to 85 years). Aortic valve replacement was performed in 564 patients (47.8%); mitral valve replacement, 478 (40.5%); and multiple valve replacement, 132 (11.2%). Concomitant procedures were performed in 337 patients (28.5%), and 140 (11.9%) had previous operations. RESULTS The early mortality was 8.1% (97), only 0.4% (5) of which were valve-related. The total follow-up was 10,405 years (mean, 8.8+/-5.2 years). The late mortality was 5.7%/patient-year (591), with the valve-related component 1.6%/patient-year (168) with a 13% reoperative mortality (56). The linearized rate of structural valve deterioration was 3.8%/patient-year (395), with overall complications of 7.1%/patient-year (737). The overall survival at 20 years was 17.2%+/-3.1% (p < 0.05; aortic valve replacement greater than mitral valve replacement or multiple valve replacement). The freedom from structural valve deterioration was, at 18 years, 25.8%+/-2.8% overall, AVR 40.6%+/-4.2%, and MVR 8.5%+/-3.4% (p < 0.05, aortic valve replacement greater than mitral valve replacement or multiple valve replacement). The freedom from structural valve deterioration for aortic valve replacement was, at 15 years, for patients older than 70 years, 82.9%+/-9.1%; 61 to 70 years, 73.2%+/-4.7%; 51 to 60 years, 58.8%+/-5.4%; 41 to 50 years, 41.7%+/-8.2%; and 21 to 40 years, 25.5%+/-7.8%. The freedom from structural valve deterioration for mitral valve replacement was, at 15 years, for patients older than 70 years, 89.8%+/-7.6%; 61 to 70 years, 22.8%+/-6.3%; 51 to 60 years, 26.3% +/- 5.7%; 41 to 50 years, 11.7%+/-5.6%; and 21 to 40 years, 7.0%+/-4.7%. CONCLUSIONS The prosthesis is recommended for aortic valve replacement for patients older than 70 years and for patients 61 to 70 years (when extended longevity is not anticipated) and for mitral valve replacement for patients older than 70 years.
The Annals of Thoracic Surgery | 1995
G. Frank; O. Tyers; W.R. Eric Jamieson; A. Ian Munro; Eva Germann; Lawrence H. Burr; Robert T. Miyagishima; Hilton Ling
From 1975 through 1992 inclusive, reoperative valve replacement (REOP) was required by 12.9% of patients (708/5,499). Of 1,355 patients with mechanical prostheses (MP), 46 (3.4%) came to REOP versus 662 of 4,144 patients (16%) with biological prostheses (BP). Early REOP mortality rate was 17.4% (8/46) for MP and 10.6% (70/662) for BP (p = not significant). It was higher with age greater than 75 years (p < 0.05) and trended higher with concomitant procedures and with increasing number of REOPs (p = not significant). The percentage freedom from REOP at 5 and 10 years for all BP was 96.0% +/- 0.4% and 74.9% +/- 1.1% compared with 93.6% +/- 1.2% and 87.9% +/- 2.5% for MP. The most common cause of REOP in the BP patients was structural valve deterioration, which was uncommon in patients with MP (72% versus 2% of REOP but only 15% versus 0.1% of initial implants). Nonstructural dysfunction was the leading cause of REOP in the MP group (65% versus 11%). Prosthetic valve endocarditis (18% versus 10%) and thromboembolic complications (10% versus 1%) were also more frequent causes of REOP in MP patients. However, the increased relative role of these factors with MP is due to the minimal incidence of structural valve deterioration. When related to the original choice of MP versus BP, only thromboembolic complication (3.8 times) was more prevalent as a cause of REOP in patients receiving MP at their previous procedure (p = not significant). For patients who previously received BP, structural valve deterioration (69 times) was more likely to lead to REOP than with MP (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
The Journal of Thoracic and Cardiovascular Surgery | 2005
V. Chan; William Robert Eric Jamieson; Eva Germann; Florence Chan; Robert T. Miyagishima; Lawrence H. Burr; Michael T. Janusz; Hilton Ling; Guy Fradet
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.
Catheterization and Cardiovascular Diagnosis | 1998
Ronald G. Carere; John G. Webb; Robert T. Miyagishima; Ognjenka Djurdev; Tanvir Ahmed; Arthur Dodek
A retrospective study was conducted to determine the frequency and nature of groin complications when the Vasoseal (Datascope Corp., NJ) hemostasis device was used on 204 occasions to enable removal of the groin sheath in anticoagulated patients. The patients had undergone balloon angioplasty (53%), coronary stenting (20%), and diagnostic angiography (27%). Complications included vascular surgery in 5% including 2 embolized collagen plugs, failure to achieve hemostasis (2%), late external bleeding (2%), purulent discharge (1.5%), a minor ooze of blood (7%), hematomas >6 cm (6%), and hematomas < or = 6 cm (7%). One or more complications occurred with 64 of 204 (30.5%) uses. Multivariate analysis identified diagnostic angiography to be associated with a reduced risk of complications [odds ratio (OR) 0.25], while stent procedure (OR 2.7) and female gender (OR 2.5) were associated with increased risk. This complication rate is similar to other reported series except for a higher rate of vascular surgery. The high incidence of anticoagulation in our study patients (94%) may explain this difference. We recommend caution and adherence to the recommended technique when the device is used in anticoagulated patients.
The Annals of Thoracic Surgery | 1989
W.R. Eric Jamieson; Lawrence H. Burr; A. Ian Munro; Robert T. Miyagishima; Alfred N. Gerein
From 1975 to 1987, 1,127 elderly patients underwent 1,223 valve replacements with the Carpentier-Edwards standard or supraannular porcine bioprostheses in 1,147 operations. Of the total patient population seen during these years, 33.5% receiving a standard porcine bioprosthesis and 48.6% receiving a supraannular bioprosthesis were 65 years of age or older. Of this elderly patient population, 465 patients were between 65 and 69 years old; 618 patients, 70 and 79 years old; and 52 patients, 80 years old and older. Aortic valve replacement was performed in 635 patients, mitral valve replacement in 417 patients, tricuspid valve replacement in 2 patients, and multiple-valve replacement in 80 patients. The cumulative follow-up was 3,957 patient-years. Early mortality was 9.5%: 7.3% for the 65- to 69-year-old group, 10.7% for the 70- to 79-year-old group, and 15.4% for the group 80 years old and older. Late mortality was 5.5% per patient-year: 4.2% per patient-year for the 65- to 69-year-old group, 6.3% per patient-year for the 70- to 79-year-old group, and 14.1% per patient-year for the group 80 years old and older. Valve-related causes contributed to 7 early deaths and 33 late deaths. The overall patient survival, including operative deaths, was 70.7% +/- 1.6% at 5 years and 47.8% +/- 3.7% at 10 and 12 years. The freedom from all valve-related complications was 52.1% +/- 6.1% at 10 and 12 years. The overall rate of valve-related complications was 5.0% per patient-year (fatal complications, 1.13% per patient-year). The overall rate of thromboembolism was 2.3% per patient-year and the freedom from thromboembolism, 69.6% +/- 5.2% at 10 and 12 years. The freedom from structural valve deterioration was 80.8% +/- 8.1% at 10 and 12 years: 71.7% +/- 11.0% at 10 and 12 years for the 65- to 69-year-old group, 97.9% +/- 1.2% at 10 years for the 70- to 79-year-old group, and 100% at 12 years for the group 80 years old and older. At 10 and 12 years, the freedom from valve-related death was 83.7% +/- 4.3% and the freedom from reoperation, 73.3% +/- 8.6%. The freedom from valve-related death, residual morbidity from thromboembolism and anticoagulant-related hemorrhage, and reoperation was 61.7% +/- 7.0% at 10 and 12 years. The clinical performance of porcine bioprostheses in the elderly patient population has been excellent. The early mortality increases in patients 70 years old or older.(ABSTRACT TRUNCATED AT 400 WORDS)
The Annals of Thoracic Surgery | 1995
Lawrence H. Burr; W.R. Eric Jamieson; A. Ian Munro; Robert T. Miyagishima; Eva Germann
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)
Circulation | 2003
W.R.E. Jamieson; Lawrence H. Burr; Robert T. Miyagishima; M.T. Janusz; Guy Fradet; Samuel V. Lichtenstein; Hilton Ling
Background—The predominant complication of bioprostheses is structural valve deterioration and the consequences of reoperation. The purpose of the study was to determine the mortality and risk assessment of that mortality for mitral bioprosthetic failure. Methods and Results—From 1975 to 1999, 1 973 patients received a heterograft bioprosthesis in 2 152 operations. The procedures were performed with concomitant coronary artery bypass (CAB) in 694 operations and without in 1 458 operations. There were 481 reoperations for structural valve deterioration performed in 463 patients with 34 fatalities (7.1%). Of the 481 re-replacements, 67 had CAB and 414 had isolated replacement; the mortality was 11.9% (8) and 6.3% (26), respectively. Eleven predictive factors inclusive of age, concomitant CAB, urgency status, New York Heart Association (NYHA; reoperation), and year of reoperation (year periods) were considered. The mortality from 1975 to 1986 was 9.8% (6/61), from 1987 to 1992 it was 10.8% (20/185), and from 1993 to 2000 it was 3.4% (8/235) (I versus III P =0.0458, II versus III P =0.0047). The mortality by urgency status was elective/urgent 6.0% (26/436) and emergent 17.8% (8/45) (P =0.00879). The mortality was NYHA I/II 0.00% (0/37), III 5.1% (14/273), and IV 11.7% (20/171) (P =0.0069). The predictive risk factors by multivariate regression analysis were age at implant, odds ratio (OR) 0.84 (P =0.0113); age at explant, OR 1.2 (P =0.0089); urgency, OR 2.8 (P =0.0264); NYHA, OR 2.5 (P =0.015); 1975–1986 versus 1993–2000 of reoperations, OR 5.8 (P =0.0062); and 1987–19 92 versus 1993–2000, OR 4.0 (P =0.0023). For the period 1993 to 2000 of reoperations, only age at implant and age at explant were significant; NYHA class, urgency status, and concomitant CAB were not significant. Conclusion—Bioprosthetic mitral reoperative mortality can be lowered by reoperations on an elective/urgent basis in low to medium NYHA functional class. The routine evaluation of patients can achieve earlier low risk reoperative surgery.
The Annals of Thoracic Surgery | 2001
W.R. Eric Jamieson; Michael T. Janusz; Lawrence H. Burr; Hilton Ling; Robert T. Miyagishima; Eva Germann
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.
The Annals of Thoracic Surgery | 1998
W.R. Eric Jamieson; Hilton Ling; Lawrence H. Burr; Guy Fradet; Robert T. Miyagishima; Michael T. Janusz; Samuel V. Lichtenstein
BACKGROUND The Carpentier-Edwards supraannular porcine bioprosthesis experience during 15 years has been evaluated to determine the incidence of structural valve deterioration by valve position in various age groupings. METHODS From 1981 to 1995, 2,943 patients older than 20 years had the prosthesis implanted in 3,024 procedures. The mean age of the population was 65.5+/-11.9 years (range, 21 to 89 years). Aortic valve replacement was performed in 1,657 patients (54.8%); mitral valve replacement, 1,092 (36.1%); multiple valve replacement, 253 (8.3%); pulmonary valve replacement, 2 (0.1%); and tricuspid valve replacement, 20 (0.7%). Concomitant procedures were performed in 1,332 patients (45.3%), and 352 (12.0%) had previous procedures. RESULTS The early mortality was 8.9% (270), only 0.4% (11) valve-related. The total follow-up was 17,471 years (mean, 5.9+/-4.1 years). The late mortality was 5.2%/ patient-year (901) with the valve-related component 1.0%/patient-year (171). The reoperation rate was 2.1%/ patient-year (369) with 4.3% mortality (16). The linearized rate of structural valve deterioration was 2.0%/patient-year (341), and overall complications, 5.9%/patient-year (1,019). The overall survival, at 15 years, was 31.1%+/2.8% (p < 0.05; aortic valve replacement greater than mitral valve replacement or multiple valve replacement). The freedom from structural valve deterioration for aortic valve replacement was, at 12 years, for patients older than 70 years, 95.3%+/-2.7%; 61 to 70 years, 92.9%+/-2.1%; 51 to 60 years, 70.1%+/-5.3%; 41 to 50 years, 60.0%+/-8.8%; and 21 to 40 years, 75.7%+/-7.3%. The freedom from structural valve deterioration for mitral valve replacement was, at 12 years, for patients older than 70 years, 66.1%+/-9.7%; 61 to 70 years, 53.1%+/-4.7%; 51 to 60 years, 52.6%+/-5.5%; 41 to 50 years, 39.3%+/-6.9%; and 21 to 40 years, 42.1%+/-9.4%. CONCLUSIONS The prosthesis is recommended for aortic valve replacement for patients older than 70 years and for patients 61 to 70 years (when extended longevity is not anticipated) and for mitral valve replacement for patients older than 70 years (when extended longevity is not anticipated).