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T E David

Publications and source records attributed to T E David.

At least 19 recordsLinked to original sources

Hemodilution during cardiopulmonary bypass is an independent risk factor for acute renal failure in adult cardiac surgery.

BACKGROUND: This observational study sought to determine whether the degree of hemodilution during cardiopulmonary bypass is independently related to perioperative acute renal failure necessitating dialysis support. METHODS: Data were prospectively collected on consecutive patients undergoing cardiac operations with cardiopulmonary bypass from 1999 to 2003 at a tertiary care hospital. The independent relationship was assessed between the degree of hemodilution during cardiopulmonary bypass, as measured by nadir hematocrit concentration, and acute renal failure necessitating dialysis support. Multivariate logistic regression was used to control for variables known to be associated with perioperative renal failure and anemia. RESULTS: Of the 9080 patients included in the analysis, 1.5% (n = 134) had acute renal failure necessitating dialysis support. There was an independent, nonlinear relationship between nadir hematocrit concentration during cardiopulmonary bypass and acute renal failure necessitating dialysis support. Moderate hemodilution (nadir hematocrit concentration, 21%-25%) was associated with the lowest risk of acute renal failure necessitating dialysis support; the risk increased as nadir hematocrit concentration deviated from this range in either direction (P = .005). Compared with moderate hemodilution, the adjusted odds ratio for acute renal failure necessitating dialysis support with severe hemodilution (nadir hematocrit concentration <21%) was 2.34 (95% confidence interval, 1.47-3.71), and for mild hemodilution (nadir hematocrit concentration >25%) it was 1.88 (95% confidence interval, 1.02-3.46). CONCLUSIONS: Given that there is an independent association between the degree of hemodilution during cardiopulmonary bypass and perioperative acute renal failure necessitating dialysis support, patient outcomes may be improved if the nadir hematocrit concentration during cardiopulmonary bypass is kept within the identified optimal range. Randomized clinical trials, however, are needed to determine whether this is a cause-effect relationship or simply an association.

Acute Kidney Injury↗

Long-term results of bioprosthetic mitral valve replacement: the pericardial perspective.

Pericardial valve bioprostheses were introduced in early 1970s and were widely used in the 1980s. The longterm results with the Ionescu-Shiley valve, the first commercially available pericardial valve, were disappointing because of high rate cusp tears during the first decade after implantation. The enthusiasm for this type of bioprosthetic valve was further hampered by the premature failure of the Hancock pericardial valve. The long-term results of aortic valve replacement with the Carpentier-Edwards pericardial valve, which was introduced in 1981, indicated that that valve was durable and the issue of cusp tears had been resolved by an appropriate design. This knowledge prompted surgeons to revisit the merits of pericardial valves for mitral valve replacement and several other pericardial valves are now commercially available. The largest data on long-term results are with the Carpentier-Edwards pericardial mitral valve. The reported freedom from structure valve failure ranged from 69% to 85% at 10 years in patient population with mean age of 60 to 70 years. Young age is a major determinant of valve failure, which is largely due to calcification. There are also long-term data, albeit more limited on the Sorin Pericarbon and Mitroflow valves used for mitral valve replacement. This paper review the published experience with various pericardial bioprosthetic valves used for mitral valve replacement during the past 3 decades.

Adult↗

Redo aortic root replacement: experience with 31 patients.

BACKGROUND: Aortic root re-replacement is being performed with increased frequency. Limited information is available regarding the surgical approaches and clinical outcomes of this reoperation. METHODS: Between May 1980 and May 1999, 31 patients (mean age, 45 +/- 15 years) underwent redo composite replacement of the aortic valve and ascending aorta. Indications for reoperation were prosthetic valve endocarditis in 12 patients (39%), failed biological valve in 17 (55%), and false aneurysm in 2 (6%). At reoperation, mechanical valves were implanted in 24 patients and biologic valves in 7. All patients with endocarditis had annular abscess and required reconstruction of the left ventricular outflow tract before implantation of a new valved conduit. Mechanical valves were used in 24 patients, aortic homograft in 4, and bioprosthetic valves in 3. The coronary button technique was used to reimplant the coronary arteries whenever possible. Extension of one or both coronary arteries with a short segment of saphenous vein or a synthetic graft was used in 16 patients (52%). The aortic arch was replaced in 7 patients (23%). RESULTS: There was one operative death (3%) because of rupture of an abdominal aortic aneurysm. The mean follow-up was 47 +/- 46 months and was 100% complete. There were five late deaths (16%), three of which were cardiac related. The actuarial survival was 71% +/- 12% at 5 years. Three patients experienced recurrent prosthetic valve endocarditis 4 months to 8 years after operation. The 8-year freedom from endocarditis for patients operated on for endocarditis was 82% +/- 11% compared with 100% for those operated on for other reasons (p = 0.1). At the last follow-up, 21 of 25 survivors (84%) were in New York Heart Association functional classes I or II, and 4 were in class III. CONCLUSIONS: Redo aortic root replacement can be performed with good early and late results. Patients operated on for prosthetic root endocarditis may have an increased risk of recurrent late endocarditis.

Adolescent↗

Fifteen-year experience with the mitral Carpentier-Edwards PERIMOUNT pericardial bioprosthesis.

BACKGROUND: This multicenter study concerning the mitral PERIMOUNT valve previously reported clinical results at 12 years; this report updates the performance to 15 years postoperatively. METHODS: The 435 patients (mean age 60.7+/-11.6 years; 41.1% male) underwent implantation with the PERIMOUNT valve between 1984 and 1989 at seven institutions. Follow-up was complete for 96.1% of the cohort. The mean follow-up was 8.1+/-4.4 years (range 0 to 15.4 years) for a total of 3492 patient-years. RESULTS: There were 34 (7.8%) operative deaths, one (0.2%) valve related. The late mortality rate was 5.3%/patient-year (2.2%/patient-year valve related). At 14 years, the overall actuarial survival rate was 37.1%+/-3.3% (63.1%+/-4.4% valve related). Actuarial freedom from complications at 14 years was as follows: thromboembolism, 83.8%+/-3.2% (1.1%/patient-year); hemorrhage, 86.6%+/-3.2% (1.1%/patient-year); and explant due to structural valve deterioration (SVD), 68.8%+/-4.7%. Actual freedom from explant due to SVD was 83.4%+/-2.3%. Rates of structural failure decreased with increasing age at implant. CONCLUSIONS: The Carpentier-Edwards PERIMOUNT Pericardial Bioprosthesis is a reliable choice for a tissue valve in the mitral position, especially in patients more than 60 years of age.

Actuarial Analysis↗

Clinical outcomes after aortic valve replacement with the Toronto stentless porcine valve.

BACKGROUND: Hemodynamic benefits of the Toronto stentless porcine valve have been documented. Clinical well-being and freedom from major valve-related events have been less well defined. METHODS: A total of 447 patients were prospectively followed for up to 8 years (1,745.2 valve years total, 3.9 valve years/patient). The patient demographics included 66% men, mean age 65 years, New York Heart Association functional class III-IV 55%, concomitant coronary artery bypass grafting 41%. RESULTS: We found that 83.7% of patients were in New York Heart Association functional class I and 80.8% had 0 to 1+ aortic insufficiency. Mean gradient at 6 years (n = 75) was 4.4 mm Hg and mean effective orifice area (EOA) 2.4 cm2. Late adverse event rates per patient per year were: embolism 1.0%, endocarditis 0.4%, thrombosis 0%, structural deterioration 0.2%, explant 0.3%, and valve-related death 0.6%. Freedom from valve-related death at 6 years was 95.8%; from cardiac death 96.3%. Freedom from endocarditis was 98.4%, from embolism 93.9%, from structural deterioration 97.4%, and freedom from explant 98.1%. For patients older than 60 years, freedom from structural deterioration was 100%. CONCLUSIONS: These results confirm satisfactory clinical outcomes after aortic valve replacement with the Toronto stentless porcine valve, with a low incidence of valve-related adverse events as long as 96 months after valve replacement.

Adult↗

The efficacy of the Cox/maze procedure combined with mitral valve surgery: a matched control study.

OBJECTIVE: To evaluate the results of the maze procedure combined with mitral valve (MV) surgery in patients with chronic atrial fibrillation (AF). METHODS: From 1994--1999, 47 patients with chronic AF underwent the maze procedure combined with MV surgery (maze group). They were compared to 47 patients matched for age, sex, left ventricular function and type of MV surgery (non-maze group). The maze group had less severe symptoms but larger left atrium, and AF of longer duration than the non-maze group. One surgeon performed all operations in both groups of patients. RESULTS: There were two early deaths in the maze group (4.5%) and one (2.2%) in the non-maze group. The duration of cardiopulmonary bypass (P=0.0001) and aortic crossclamping (P=0.0001) were greater in the maze group. Mean follow-up was 26+/-3 months in the maze group and 32+/-4 months in the non-maze group, and was 100% complete. Three-year survival was 96+/-3% for the maze group compared to 85+/-7% for the non-maze group (P=0.16). At the latest follow-up, 75% of the maze patients were in sinus rhythm compared to 36% of the non-maze patients (P=0.0004); 38% of the maze group were on coumadin postoperatively, compared to 69% in the non-maze group (P=0.003); and patients in the maze group were on fewer antiarrhythmic medications (P=0.0002). Three-year freedom from thromboembolic complications was 100% for the maze group compared to 83+/-7% for the non-maze group (P=0.03). CONCLUSIONS: In this retrospective study the maze procedure did not seem to increase operative mortality of MV surgery, was effective in eliminating atrial fibrillation, and reduced the risk of thromboembolic complications and the need for long-term anticoagulation after mitral valve repair or replacement with a bioprosthesis.

Aged↗

Aortic valve-sparing operations for aortic root aneurysm.

The object of this report is to review the clinical outcomes of aortic valve-sparing operations in patients with aortic root aneurysm. From May 1988 to June 2000, 120 patients with aortic root aneurysm with or without aortic insufficiency underwent aortic valve-sparing operations. There were 83 men and 37 women whose mean age was 46 years (range 16 to 72 years). Forty-eight patients had the Marfan syndrome, and 22 had either acute or chronic type A aortic dissections. Reconstruction of the aortic root was performed using the technique of reimplanation of the aortic valve in 64 patients and the remodeling of the aortic root in 56. The mean follow-up was 35 months (range 2 to 145 months), and it was complete. Aortic valve function was assessed by echocardiography. There were 2 operative and 5 late deaths. The 10-year survival for patients with aortic root aneurysm was 88% +/- 4%. Two patients have required aortic root replacement: one on the first postoperative day because of severe aortic insufficiency and one paraplegic patient 12 years after surgery because of infective endocarditis with aortic root abscess. Both patients survived reoperation. The 10-year freedom from aortic root reoperation was 99% +/- 1%. Three patients suffered transient ischemic attacks. The 10-year freedom from thromboembolic events was 89% +/- 5%. Seven patients had moderate aortic insufficiency at the latest echocardiographic study. The 10-year freedom from severe or moderate aortic insufficiency was 83% +/- 8%. Aortic valve-sparing operations have provided excellent clinical outcomes and few valve-related complications. The function of the reconstructed aortic root remains unchanged in most patients during the first decade of follow-up.

Adult↗

Late results of heart valve replacement with the Hancock II bioprosthesis.

OBJECTIVE: To review the late clinical outcomes of patients who had isolated aortic or mitral valve replacement with the Hancock II bioprosthesis. METHODS: From 1982 to 1994, 670 patients underwent isolated aortic valve replacement and 310 underwent isolated mitral valve replacement with the Hancock II bioprosthesis (Medtronic Inc, Minneapolis, Minn). Mean age was 65 +/- 12 years in both groups. Most patients were in New York Heart Association functional classes III or IV, and concomitant coronary artery disease was present in 44% of patients in the aortic valve group and 41% of patients in the mitral valve group. Patients were followed up prospectively at periodic intervals. Mean follow-up was 87 +/- 45 months in the aortic valve group and 83 +/- 50 months in the mitral valve group, and it was 99% complete. RESULTS: Actuarial survival at 15 years was 47% +/- 3% in the aortic valve group and 30% +/- 5% in the mitral valve group. Older age, advanced functional class, impaired left ventricular function, active endocarditis, and coronary artery disease were independent predictors of late death. The freedom from thromboembolic complications at 15 years was 83% +/- 3% in the aortic and 87% +/- 3% in the mitral valve group. The freedom from infective endocarditis at 15 years was 96% +/- 1% in the aortic and 91% +/- 1% in the mitral valve group. At 15 years, the actuarial and actual freedom from structural valve deterioration was 81% +/- 5% and 90% +/- 3%, respectively, in the aortic group and 66% +/- 6% and 83% +/- 3%, respectively, in the mitral group. Younger age, mitral valve position, and poor ventricular function were independent predictors of structural valve deterioration. The freedom from repeat valve replacement at 15 years was 77% +/- 5% in the aortic group and 69% +/- 6% in the mitral. The vast majority of patients had functional improvement after valve replacement. CONCLUSIONS: The Hancock II bioprosthesis has provided good clinical outcomes and is a durable valve, particularly in the aortic position in older patients.

Adolescent↗

Results of aortic valve-sparing operations.

OBJECTIVE: To review the late results of valve-sparing operations in patients with aortic root aneurysm and in those with ascending aortic aneurysm and aortic insufficiency. METHODS: From May 1988 to June 2000, 120 patients with aortic root aneurysm and 68 with ascending aortic aneurysm and aortic insufficiency underwent aortic valve-sparing operations. Patients with aortic root aneurysm were younger, were predominantly male, and had less severe aortic insufficiency than patients with ascending aortic aneurysm, who were older and often had aneurysm of the transverse arch. Forty-eight patients with aortic root aneurysm had the Marfan syndrome. The prevalence of aortic dissection was similar in both groups. Reconstruction of the aortic root was performed by reimplanation of the aortic valve in 64 patients and by remodeling of the aortic root in 56. Patients with ascending aortic aneurysm and aortic insufficiency were treated by replacement of the ascending aorta with reduction in the diameter of the sinotubular junction. Approximately two thirds of the latter patients also required replacement of the transverse aortic arch. The mean follow-up was 35 +/- 31 months for patients with aortic root aneurysm and 26 +/- 23 months for those with ascending aortic aneurysm. RESULTS: There were 2 operative and 5 late deaths in patients with aortic root aneurysm and 1 operative and 9 late deaths in patients with ascending aortic aneurysm. The 5-year survival for patients with aortic root aneurysm was 88% +/- 4% and for patients with ascending aortic aneurysm, 68% +/- 12% (P =.01). Severe aortic insufficiency developed in 2 patients, and they required aortic valve reoperation. The 5-year freedom from aortic valve reoperation was 99% +/- 1% for patients with aortic root aneurysm and 97% +/- 4% for those with ascending aortic aneurysm. Seven patients had moderate aortic insufficiency at the latest echocardiographic study. The 5-year freedom from severe or moderate aortic insufficiency was 90% +/- 4% in patients who had aortic root aneurysm and 98% +/- 2% in those who had ascending aortic aneurysm. CONCLUSIONS: Aortic valve-sparing operations have provided excellent clinical outcomes and few valve-related complications. The function of the reconstructed aortic root remains unchanged in most patients during the first 5 years of follow-up.

Adult↗

Dilation of the sinotubular junction causes aortic insufficiency after aortic valve replacement with the Toronto SPV bioprosthesis.

OBJECTIVE: This study was undertaken to examine the causes of late aortic insufficiency in patients who had aortic valve replacement with the Toronto SPV bioprosthesis (St Jude Medical, Inc, St Paul, Minn). METHODS: From 1991 to 1996, 174 patients with a mean age of 63 +/- 11 years underwent aortic valve replacement with the Toronto SPV bioprosthesis and were evaluated annually by Doppler echocardiographic studies to assess valve function. The diameters of the aortic root were retrospectively measured in all patients who had aortic insufficiency and also in a random sample of 23 patients without aortic insufficiency. The mean follow-up was 5.8 years (range 4 to 9 years). RESULTS: Aortic insufficiency greater than 1+ developed in 19 patients. The diameter of the sinotubular junction increased in these patients and did not change in those without aortic insufficiency. The ratio between the diameter of the sinotubular junction and the size of the Toronto SPV bioprosthesis increased in patients who had aortic insufficiency and did not change in those without aortic insufficiency. Both 2-way analysis of covariance and analysis by a mixed linear model demonstrated a significant difference in slopes between the patients with aortic insufficiency greater than 1+ and in those without insufficiency for the ratio of the diameter of the sinotubular junction/diameter of the Toronto SPV relationships over time (aortic insufficiency. Year; P <.001). Structural valve deterioration was observed in 5 valves, and in 4 of them the sinotubular junction of the aortic root had dilated. The freedom from structural valve deterioration was 99% +/- 1% for patients without aortic insufficiency and 82% +/- 12% for those with aortic insufficiency of more than 1+ at 8 years (P =.004). One patient had moderate aortic insufficiency without structural valve deterioration and dilation of the sinotubular junction. CONCLUSIONS: Dilation of the sinotubular junction causes aortic insufficiency after aortic valve replacement with the Toronto SPV bioprosthesis and increases the risk of structural valve deterioration. Banding the sinotubular junction may prevent dilation and enhance the durability of this valve.

Aortic Valve↗

Mid-term results of the Ross procedure.

Although the Ross procedure has been performed for over three decades, its role in the management of patients with aortic valve disease is not well established. This study reviews our experience with this operation. From 1990 to 1999, 155 patients underwent the Ross procedure. The mean age of 106 men and 49 women was 35 years. Most patients (85%) had congenital aortic valve disease. The pulmonary autograft was implanted in the subcoronary position in 2 patients, as an aortic root inclusion in 78, and aortic root replacement in 75. The follow-up extended from 9 to 114 months, mean of 45 +/- 28 months, and it was complete. All patients have had Doppler echocardiographic studies. There was only one operative and one late death. The survival was 98% at 7 years. The freedom from 3+ or 4+ aortic insufficiency was 86% at 7 years and the freedom from reoperation on the pulmonary autograft was 95% at 7 years. Dilation of the aortic annulus and/or sinotubular junction was the most common cause of aortic insufficiency. One patient required three reoperations on the biological pulmonary valve. Most patients (96%) have no cardiac symptoms. The Ross procedure has provided excellent functional results in most patients, but progressive aortic insufficiency due to dilation of the aortic annulus and/or sinotubular junction is a potential problem in a number of patients.

Adolescent↗

Aortic valve repair for adult congenital heart disease: A 22-year experience.

BACKGROUND: Aortic valve-preserving procedures have resulted in excellent outcomes in selected patients, particularly those with normal aortic valve leaflets and dilated aortic roots. However, several congenital heart lesions are associated with abnormal aortic valve leaflets. The long-term results of aortic valve repair for these lesions are not well defined. METHODS AND RESULTS: We reviewed the clinical records of 54 adult (age >18 years) patients who underwent repair of congenital abnormalities of the aortic valve between 1976 and September 1999. Follow-up data were available on 52 (96%) patients (mean 50+/-67 months, range 1 to 266). Patients underwent repair at a mean age of 34+/-14 years with associated diagnoses of subaortic stenosis (n=10), ventricular septal defect with prolapsing aortic valve (n=17), bicuspid aortic valve (n=23), sinus of Valsalva aneurysm (n=10), and bacterial endocarditis (n=2). There was 1 operative death (1.9%) and 3 late deaths. Survival at 5 and 10 years was 98+/-2% and 74+/-12%, respectively. Freedom from reoperation was 74+/-9% and 51+/-15% at 5 and 10 years, respectively. The presence of a ventricular septal defect predicted failure of valve repair (59% versus 22%, P:=0.01). A bicuspid aortic valve, subaortic stenosis, or the requirement for mitral valve surgery did not affect outcomes. CONCLUSIONS: Aortic valve repair in adult patients with congenital heart disease can be performed with minimal morbidity and mortality rates. The medium-term results of repair are acceptable, regardless of valvular or associated pathology. However, only 31 patients (57%) demonstrated long-term competence of the aortic valve, suggesting that most adult patients with congenital aortic valve disease will eventually require aortic valve replacement.

Adult↗

Prosthesis-patient mismatch affects survival after aortic valve replacement.

BACKGROUND: Surgeons traditionally avoid the use of "small" aortic prostheses because of the potential for residual left ventricular outflow tract obstruction and persistent transvalvular gradients. This study examines the ratio between prosthetic valve size and the body surface area (BSA) of patients undergoing aortic valve replacement (AVR). We sought to determine the effect of potential "prosthesis-patient" mismatch on long-term survival. METHODS AND RESULTS: Follow-up was conducted on 2981 patients who underwent AVR with stented bioprostheses between 1976 and 1996. To account for differences between manufacturers' labeled valve sizes, we calculated the ratio between the prosthetic valve effective orifice area (EOA) and the patient's BSA (recorded for 2154 patients). The lowest decile in this cohort had a calculated EOA/BSA of <0.75 cm(2)/m(2) (Small group, n=227) compared with the control group (n=1927), in whom the EOA/BSA ratio was >0.75 cm(2)/m(2). Operative mortality was higher in the Small group (8% versus 5%, P:=0.03). Actuarial survival at 12 years was 50+/-5% in the Small group compared with 49+/-2% in the control group (P:=0.27). However, freedom from valve-related mortality was significantly lower in the Small group (75+/-5% versus 84+/-2%, P:=0.004). Cox regression analysis determined age and NYHA functional class to be the multivariate predictors of overall mortality, whereas advanced age and EOA/BSA <0.75 cm(2)/m(2) were found to be the predictors of valve-related mortality. CONCLUSIONS: Prosthesis-patient mismatch results in significantly higher early and late mortality after bioprosthetic AVR. We recommend careful selection of stented bioprostheses to ensure an adequate ratio of EOA to BSA. An EOA/BSA ratio of >0.75 cm(2)/m(2) may avoid residual left ventricular outflow tract obstruction and persistent transvalvular gradients. Careful prosthesis-patient matching will improve both early and late survival after AVR.

Aortic Valve↗

Predictive accuracy study: comparing a statistical model to clinicians' estimates of outcomes after coronary bypass surgery.

BACKGROUND: The purpose of this study was to compare clinicians' prior probability estimates of operative mortality (OM) and prolonged intensive care unit stay (ICU) length of stay greater than 48 hours after coronary artery bypass graft surgery (CABG) with estimates derived from statistical models alone. METHODS: Nine clinicians estimated the predicted probability of OM and ICU stay greater than 48 hours from an abstract of information for each of 100 patients selected from the 1996 to 1997 database of 1,904 patients who underwent isolated CABG. Logistic regression models were used to calculate the predicted probability of OM and ICU stay greater than 48 hours for each patient. The study sample was split into two parts; clinicians were randomly given access to a predictive rule to guide their judgements for one part of the study. RESULTS: Clinicians' estimates were similar with or without access to the rule, and both parts of the study were therefore pooled. Clinicians significantly overestimated the probability of OM (model 6.3% +/- 1%, clinicians 7.6% +/- 3%, p = 0.0001) and ICU stay greater than 48 hours (model 25% +/- 2%, clinicians 28% +/- 1%, p = 0.0012). Clinicians' estimates of OM were not significantly higher than the model's for nonsurvivors (0.8% +/- 0.7%, p = 0.2), but were significantly higher for survivors (1.4% +/- 0.3%, p = 0.039). CONCLUSIONS: Clinicians trusted their own empiric estimates rather than a predictive rule and overestimated the probability of OM and ICU stay greater than 48 hours.

Aged↗

Ruptured sinus of valsalva aneurysm: early recurrence and fate of the aortic valve.

BACKGROUND: We reviewed our experience with congenital ruptured sinus of Valsalva aneurysms (RSVA) to determine patterns of early recurrence and the fate of the aortic valve (AV). METHODS: Over a 28-year period, RSVA was identified in 34 patients, (mean age 31.6 years). Primary closure of the RSVA was performed in 10 patients, and a patch employed in 24. Aortic insufficiency was present in 24 patients. AV replacement (AVR) was performed in 5 patients; AV repair in 6. RESULTS: Follow-up of 9.2 +/- 8.3 years (6 months to 24 years) was complete in all but 2 patients. Five early fistula recurrences (in 4 patients) correlated with primary rather than patch closure (p < 0.03). Kaplan-Meier survival at 10 years is 90 +/- 7%. Freedom from reoperative AVR at 10 years is 83 +/- 9%. Late AVR was performed in 6 patients for progressive aortic insufficiency due to bicuspid valve (n = 3), cusp disease of affected sinus (n = 2), or aortic root dilatation (n = 2). CONCLUSIONS: Patch closure of the RSVA should be routinely employed. A bicuspid valve may be associated with the late need for AVR.

Adolescent↗

Risk factors for late pulmonary homograft stenosis after the Ross procedure.

BACKGROUND: We reviewed our experience with the Ross procedure to identify the prevalence and predictors of late pulmonary homograft stenosis. METHODS: Between June 1992 and December 1997, 109 consecutive patients (age 34.5 +/- 8.6 years) underwent the Ross procedure, with reconstruction of the right ventricular outflow tract with a cryopreserved pulmonary homograft (22 to 30 mm diameter). There was one early and one late death. Echocardiographic follow-up was available in 105 of 108 patients (97%), with a follow-up of 39 +/- 20 months. Homograft donor and preservation measurements and patient variables were subjected to multivariable analyses to identify independent predictors of late homograft performance. RESULTS: The major physiopathologic finding was homograft stenosis. Peak systolic gradients across the homograft were 20 mm Hg or more in 30 of 105 patients (28.5%) and 40 mm Hg or more in 4 of 105 patients (3.8%). One patient required two re-replacements of her homograft for severe stenosis. Moderate or severe homograft insufficiency was noted in 10 of 105 patients (9.5%). The independent predictors of late pulmonary homograft stenosis were younger donor age (p = 0.03), shorter duration of cryopreservation (p = 0.01), and smaller homograft size (p = 0.06). Beating heart donor status, short homograft ischemic time, and other factors that have been shown to be associated with increased graft viability were associated with graft stenosis but did not reach statistical significance. However, mean gradients across the homograft were significantly related (p = 0.002) to the number of these risk factors in each patient. CONCLUSIONS: Stenosis of the pulmonary homograft can be a significant problem following the Ross procedure, and was predicted by younger donor age and shorter duration of cryopreservation. These factors may be related to increased cellular viability, which might actually predispose to late homograft stenosis in a subgroup of patients.

Adolescent↗

Histology and morphology of 59 internal thoracic artery grafts and their distal anastomoses.

BACKGROUND: The left internal thoracic artery (LITA) is accepted as a superior graft for the left coronary system because of its better long-term patency rate than saphenous grafts. The postsurgical histomorphometric changes at the distal anastomosis of LITA grafts are not well documented. METHODS: The cellular changes within the intima of 59 LITA grafts were analyzed by light microscopy. RESULTS: Grafts implanted 1 week or less (n = 34) showed no postsurgical tissue proliferation. Of the 7 grafts implanted 1 to 8 weeks, only the suture sites exhibited intimal thickening (6 of 7 grafts, 0.08 +/- 0.07 mm). The remaining grafts (n = 18), aged 2 months to 10 years, showed significant intimal thickening at the suture sites (0.39 +/- 0.17 mm) and on the hood (0.29 +/- 0.25 mm), with variable thickening on the floor (10 of 18 left anterior descending coronary arteries, 0.11 +/- 0.12 mm). The graft body showed insignificant intimal changes (10 of 18, 0.03 +/- 0.04 mm), with mild focal atherosclerotic lesions in 2 of 18 late LITA grafts. CONCLUSIONS: Left internal thoracic artery grafts develop fibromuscular intimal hyperplasia primarily around the anastomosis. The response on the hood appears to be a hemodynamic response, secondary to that of the suture sites.

Aged↗