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Delos M Cosgrove

Publications and source records attributed to Delos M Cosgrove.

52 records · Page 3Linked to original sources
PubMed2003

Mitral valve repair with aortic valve replacement is superior to double valve replacement.

OBJECTIVES: Double valve replacement has been advocated for patients with combined aortic and mitral valve disease. This study investigated the alternative that, when feasible, mitral valve repair with aortic valve replacement is superior. PATIENTS AND METHODS: From 1975 to 1998, 813 patients underwent aortic valve replacement with either mitral valve replacement (n = 518) or mitral valve repair (n = 295). Mitral valve disease was rheumatic in 71% and degenerative in 20%. Mitral valve replacement was more common in patients with severe mitral stenosis (P =.0009), atrial fibrillation (P =.0006), and in patients receiving a mechanical aortic prosthesis (P =.0002). These differences were used for propensity-matched multivariable comparisons. Follow-up extended reliably to 16 years, mean 6.9 +/- 5.9 years. RESULTS: Hospital mortality rate was 5.4% for mitral valve repair and 7.0% for replacement (P =.4). Survivals at 5, 10, and 15 years were 79%, 63%, and 46%, respectively, after mitral valve repair versus 72%, 52%, and 34%, respectively, after replacement (P =.01). Late survival was increased by mitral valve repair rather than replacement (P =.03) in all subsets of patients, including those with severe mitral valve stenosis. After repair of nonrheumatic mitral valves, 5-, 10-, and 15-year freedom from valve replacement was 91%, 88%, and 86%, respectively; in contrast, after repair of rheumatic valves, it was 97%, 89%, and 75% at these intervals. CONCLUSIONS: In patients with double valve disease, aortic valve replacement and mitral valve repair (1) are feasible in many, (2) improve late survival rates, and (3) are the preferred strategy when mitral valve repair is possible.

Adult↗
PubMed2003

Repair versus replacement for degenerative mitral valve disease with coexisting ischemic heart disease.

OBJECTIVE: We sought to compare mitral valve repair and replacement as treatments for degenerative mitral valve disease with coexisting ischemic heart disease. Specifically, we sought to (1) identify differences between patients undergoing repair and replacement, (2) determine whether the choice of mitral valve procedure affected survival after adjusting for those differences, and (3) discover which patients were predicted to benefit from mitral valve repair and which from replacement. METHODS: From 1973 to 1999, 679 patients (mean age, 67 +/- 9.1 years; 73% men) with degenerative mitral valve and ischemic heart diseases underwent combined coronary artery bypass grafting and either mitral valve repair (66%) or replacement (34%). Factors associated with repair and replacement were used for multivariable propensity matching. Risk factors for death were identified by means of multivariable, multiphase hazard-function analysis. RESULTS: Patients more likely to undergo repair had isolated posterior chordal rupture (P <.0001) or more recent date of operation (P <.0001); those more likely to undergo replacement were older (P =.0003) or had bileaflet prolapse (P <.0001). Unadjusted survival at 30 days and 1, 5, and 10 years was 97%, 92%, 79%, and 59% after repair and 94%, 88%, 70%, and 37% after replacement. After adjusting for comorbid factors, the extent and effect of ischemic heart disease, and propensity score, the survival benefit of repair became evident after 2 years (P =.01). Eighty-nine percent of patients were predicted to benefit from repair. CONCLUSIONS: In patients with degenerative mitral valve and ischemic heart diseases, mitral valve repair confers a survival advantage over replacement that becomes evident about 2 years after the operation.

Aged↗
PubMed2003

Vacuum-assisted venous return reduces blood usage.

OBJECTIVE: To determine whether vacuum-assisted venous return has clinical advantages over conventional gravity drainage apart from allowing the use of smaller cannulas and shorter tubing. METHODS: A total of 150 valve operations were performed at our institution between February and July 1999 using vacuum-assisted venous return with small venous cannulas connected to short tubing. These were compared with (1) 83 valve operations performed between April 1997 and January 1998 using the initial version of vacuum-assisted venous return, and (2) 124 valve operations performed between January and April of 1997 using conventional gravity drainage. Priming volume, hematocrit value, red blood cell usage, and total blood product usage were compared multivariably. These comparisons were covariate and propensity adjusted for dissimilarities between the groups and confirmed by propensity-matched pairs analysis. RESULTS: Priming volume was 1.4 +/- 0.4 L for small-cannula vacuum-assisted venous return, 1.7 +/- 0.4 L for initial vacuum-assisted venous return, and 2.0 +/- 0.4 L for gravity drainage (P <.0001). Smaller priming resulted in higher hematocrit values both at the beginning of cardiopulmonary bypass (27% +/- 5% compared with 26% +/- 4% and 25% +/- 4%, respectively, P <.0001) and at the end (30% +/- 4% compared with 28% +/- 4% and 27% +/- 4%, respectively, P <.0001). Red cell transfusions were used in 17% of the patients having small-cannula vacuum-assisted venous return, 27% of the initial patients having vacuum-assisted venous return, and 37% of the patients having gravity drainage (P =.001); total blood product usage was 19%, 27%, and 39%, respectively (P =.002). Although ministernotomy also was associated with reduced blood product usage (P <.004), propensity matching on type of sternotomy confirmed the association of vacuum-assisted venous return with lowered blood product usage. CONCLUSIONS: Vacuum-assisted venous return results in (1) higher hematocrit values during cardiopulmonary bypass and (2) decreased red cell and total blood product usage.

Blood Circulation↗
PubMed2003

Prosthesis size and long-term survival after aortic valve replacement.

OBJECTIVE: This study was undertaken to quantify the relationship between prosthesis size adjusted for patient size (prosthesis-patient size) and long-term survival after aortic valve replacement. METHODS: Data from nine representative sources on 13,258 aortic valve replacements provided 69,780 patient-years of follow-up (mean 5.3 +/- 4.7 years), with reliable survival estimates to 15 years. Prostheses included 5757 stented porcine xenografts, 3198 stented bovine pericardial xenografts, 3583 mechanical valves, and 720 allografts. Manufacturers' labeled prosthesis size was 19 mm or smaller in 1109 patients. Expressions of prosthesis-patient size assessed were indexed internal prosthesis orifice area (in centimeters squared per square meter of body surface area) and standardized internal prosthesis orifice size (Z, the number of SDs from mean normal native aortic valve size). Multivariable hazard domain analysis with balancing score and risk factor adjustment quantified the association of prosthesis-patient size with survival. RESULTS: Prosthesis-patient size down to at least 1.1 cm(2)/m(2) or -3 Z did not adversely affect intermediate- or long-term survival (P >.2). However, 30-day mortality increased 1% to 2% when indexed orifice area fell below 1.2 cm(2)/m(2) (P =.002) or standardized orifice size fell below -2.5 Z (P =.0003). The increased early risk affected fewer than 1% of patients receiving bioprostheses but about 25% of those receiving mechanical devices. CONCLUSIONS: Aortic prosthesis-patient size down to 1.1 cm(2)/m(2) or -3 Z did not reduce intermediate- or long-term survival after aortic valve replacement. However, patient-prosthesis size under 1.2 cm(2)/m(2) or -2.5 Z was associated with a 1% to 2% increase in 30-day mortality. Prosthesis-patient sizes this small or smaller were rarely implanted in patients receiving bioprostheses.

Aged↗
PubMed2003

Current status of mitral valve repair.

Mitral valve repair is the procedure of choice to treat mitral valve dysfunction. Advantages of mitral valve repair over mitral valve replacement include improved long-term survival, better preservation of left ventricular function, and greater freedom from endocarditis, thromboembolism, and anticoagulant-related hemorrhage. The feasibility and durability of mitral valve repair depend upon the etiology of mitral valve dysfunction. In degenerative and ischemic mitral valve diseases, valve repair is possible in 90% of cases and freedom from reoperation is high. In contrast, rheumatic valves are less amenable to repair and durability is limited. Most isolated valve operations can be performed in a minimally invasive fashion using a partial upper sternotomy. In patients with atrial fibrillation and mitral valve disease, the Maze procedure or pulmonary vein isolation is performed, eliminating atrial fibrillation and the need for long-term anticoagulation.

Adult↗
PubMed2002

Clinical, echocardiographic, and biomechanical differences in mitral valve prolapse affecting one or both leaflets.

Mitral valve prolapse (MVP) is the most common cause of severe mitral regurgitation necessitating surgical correction. Unileaflet prolapse (ULP), usually involving the posterior leaflet, is more common than bileaflet prolapse (BLP), which is more difficult to repair. Little is known about clinical, echocardiographic, and biomechanical differences between ULP and BLP. In this study, biomechanical testing was performed on mitral valve leaflets and chordae obtained at operation for severe mitral regurgitation. Preoperative clinical characteristics and echocardiographic measurements were obtained on surgical patients (ULP = 88, BLP = 37). Men outnumbered women by a factor of 4:1 in ULP, and by 3:1 in BLP. Patients with BLP were younger (53.2 +/- 1.7 vs 59.5 +/- 1.1 years) than those with ULP, and this difference was greater in women (48.9 +/- 2.5 vs 62.9 +/- 2.2 years). BLP patients were less likely to be hypertensive, and more likely to undergo valve replacement rather than repair. Echocardiography showed that BLP leaflets were longer and thicker than ULP leaflets. The severity of mitral regurgitation was similar in both groups, although ULP patients had a much higher incidence of flail leaflets (45% vs 5% in BLP). Mechanical strength of chordae was greater in BLP than in ULP, although leaflet strength was similar. The increased chordal strength in BLP may be responsible for less flail. In patients with MVP and severe mitral regurgitation requiring surgery, ULP and BLP are distinct entities with substantial differences in the population affected, in echocardiographic manifestations including prevalence of flail, in chordal mechanics, and in the likelihood of surgical repair.

Biomechanical Phenomena↗
PubMed2002

Hemodynamic stability during 17 years of the Carpentier-Edwards aortic pericardial bioprosthesis.

BACKGROUND: Long-term stability of the hemodynamic performance of commercially available Carpentier-Edwards stented bovine pericardial aortic bioprostheses (Perimount RSR) is unknown. To anticipate the fate of this bioprosthesis, we examined its hemodynamic performance up to 17 years using echocardiographic studies in a Premarket Approval cohort. METHODS: Of 267 patients at four institutions in the Premarket Approval cohort, 85 had a total of 168 echocardiographic studies during a 17-year period of yearly follow-up examinations. These were reviewed and quantified in a core echocardiographic facility. Longitudinal data analysis was used to account for repeated, censored data. RESULTS: Mean transvalvular gradient was inversely related to prosthesis size (p = 0.01), and possibly (p = 0.06) increased somewhat during the first 10 years of follow-up, then stabilized. Effective orifice area was larger in larger valve sizes (p = 0.01), declined somewhat during the first 10 years, and then began to increase again. Ejection fraction declined minimally (p = 0.2). In contrast to the rather stable hemodynamics, aortic regurgitation steadily increased from none to 1 to 2+ (p = 0.005), but rarely (< 10% at 17 years) progressed to 3+ or 4+. CONCLUSIONS: The Carpentier-Edwards aortic pericardial bioprosthesis can be anticipated to have an acceptable long-term transvalvular gradient and effective orifice size that will change trivially up to 17 years after implantation. Mild aortic regurgitation will develop progressively. This anticipated hemodynamic resilience supports continued clinical use of the Perimount Carpentier-Edwards bovine pericardial stented bioprosthesis.

Adult↗
PubMed2002

Endocarditis after mitral valve repair.

BACKGROUND: Native valve endocarditis is frequently managed with antibiotics alone, but prosthetic valve endocarditis usually requires an early operation. What is the best treatment of endocarditis after mitral valve repair? METHODS: From 1986 to 2000, 22 patients were treated for endocarditis affecting a previously repaired mitral valve. Causes of mitral valve dysfunction that led to repair were degenerative (11 patients), ischemic (5 patients), endocarditic (3 patients), rheumatic (2 patients), and functional (1 patient). Endocarditis was active in 21 patients and healed in 1. Interval from initial mitral valve repair to onset of endocarditis ranged from 1 week to 10.3 years (median, 6 months). Pathology included leaflet vegetation (15), annuloplasty vegetation (4), leaflet perforation (5), and abscess (3). Mean follow-up was 3.9 +/- 3.3 years. RESULTS: Fifteen patients underwent repeat mitral valve operations with freedom from mitral valve reoperation of 65%, 41%, and 26% at 30 days, 1 year, and 5 years after onset of endocarditis. After a high early hazard, risk of reoperation fell to 10.8% per year. Seven patients, all with a leaflet vegetation, were treated with antibiotics alone. Antibiotics eradicated infection in all; however all had mitral regurgitation 2+ to 4+. Survival was 96%, 74%, and 68% at 30 days, 1 year, and 5 years. Endocarditis recurred in 1 patient (92% free of event). CONCLUSIONS: Most patients that have endocarditis develop after mitral valve repair require reoperation. However if infection is limited to a leaflet, early reoperation may be unnecessary because antibiotics alone can eradicate infection.

Adolescent↗
PubMed2002

Microwave ablation of atrial fibrillation during mitral valve operations.

Although the Cox-Maze III procedure cures atrial fibrillation in the majority of patients, it has not had widespread application. Development of new operations that use alternate energy sources and different lesion sets have caused resurgence in the surgical treatment of atrial fibrillation. Microwave creates lines of conduction block by thermal damage and subsequent scar formation. We describe a rapid and simple technique for microwave ablation of atrial fibrillation in patients having mitral valve operations.

Atrial Fibrillation↗
PubMed2002

Aortic root replacement with cryopreserved allograft for prosthetic valve endocarditis.

UNLABELLED: BACKGROUND Our strategy has been to treat aortic prosthetic valve endocarditis (PVE) with radical debridement of infected tissue and aortic root replacement with a cryopreserved aortic allograft. This study examines the effectiveness of this strategy on hospital mortality and morbidity, recurrent endocarditis, and survival. METHODS: From 1988 through 2000, 103 patients with aortic PVE underwent root replacement with a cryopreserved aortic allograft. Abscesses were present in 78%, and aortoventricular discontinuity was present in 40%. Thirty-two patients had at least one previous operation for endocarditis. In 23 patients with a history of native valve endocarditis, the allograft was implanted after one episode (17 patients), two episodes (5 patients), or three episodes of PVE (1 patient). In the 80 patients without a history of native valve endocarditis, the allograft was placed after one previous aortic valve replacement (57 patients), two (19), or three (4) previous aortic valve replacements. Among the 92 patients with positive cultures, 52 had staphylococcal organisms, 20 had streptococcal, 6 had fungal, 4 had gram-negative, and 6 had enterococcal organisms. Mean follow-up was 4.3 +/- 2.9 years. RESULTS: Hospital mortality was 3.9%. Permanent pacemakers were required in 31 patients. Survival at 1 year, 2 years, 5 years, and 10 years was 90%, 86%, 73%, and 56%, respectively, with a risk of 5.3% per year after 6 months. Four patients underwent reoperation for recurrent PVE of the allograft (95% freedom from recurrent PVE at > or = 2 years). Risk of recurrent PVE peaked at 9 months and then declined to a low level by 18 months. CONCLUSIONS: A strategy of radical debridement and aortic root replacement with a cryopreserved aortic allograft for aortic PVE is safe, effective, and recommended.

Abscess↗
PubMed2002

Reoperative cryopreserved root and ascending aorta replacement for acute aortic prosthetic valve endocarditis.

BACKGROUND: Prosthetic aortic valve endocarditis (PVE) is an important complication of aortic valve replacement (AVR) and is a particularly difficult situation after an operation combining AVR with ascending aortic replacement. METHODS: From 1988 through 2000, 27 patients with aortic valve PVE after previous ascending aortic replacement (aortic root replacement in 13, aortic valve replacement with a supracoronary graft in 14) underwent reoperation for aortic root replacement with a cryopreserved aortic allograft and prolonged intravenous antibiotic therapy. All patients were considered to have active PVE (25 with positive cultures); root abscess formation was present in 89% and aortoventricular discontinuity in 41%. RESULTS: One patient (3.7%) died in-hospital, and permanent pacemakers were required in 10 patients (37%). Mean postoperative follow-up interval was 3.9 +/- 3.0 years, and survival at 1, 2, 5, and 7.5 years was 92%, 88%, 70%, and 56%, respectively. One patient underwent reoperation for recurrent PVE 8 months after operation. CONCLUSIONS: Radical debridement of infected prosthetic material and tissue, and allograft aortic root and ascending aorta replacement, combined with intravenous antibiotic therapy, appears to achieve a low hospital mortality and a high degree of freedom from recurrent infection for patients with PVE after AVR and ascending aortic replacement.

Abscess↗
PubMed2002

Does off-pump coronary surgery reduce morbidity and mortality?

OBJECTIVE: To compare hospital outcomes of on-pump and off-pump coronary artery bypass surgery. METHODS: From 1997 to 2000, primary coronary artery bypass grafting was performed in 481 patients off pump and in 3231 patients on pump. Hospital outcomes were compared between propensity-matched pairs of 406 on-pump and 406 off-pump patients. The 2 groups were similar in age (P =.9), left ventricular function (P =.7), extent of coronary artery disease (P =.5), carotid artery disease (P =.4), and chronic obstructive pulmonary disease (P =.5). However, off-pump patients had more previous strokes (P =.05) and peripheral vascular disease (P =.02); on-pump patients had a higher preoperative New York Heart Association class (P =.01). RESULTS: In the matched pairs the mean number of bypass grafts was 2.8 +/- 1.0 in off-pump patients and 3.5 +/- 1.1 in on-pump patients (P <.001). Fewer grafts were performed to the circumflex (P <.001) and right coronary (P =.006) artery systems in the off-pump patients. Postoperative mortality, stroke, myocardial infarction, and reoperation for bleeding were similar in the 2 groups. There was more encephalopathy (P =.02), sternal wound infection (P =.04), red blood cell use (P =.002), and renal failure requiring dialysis (P =.03) in the on-pump patients. CONCLUSIONS: Both off- and on-pump procedures produced excellent early clinical results with low mortality. An advantage of an off-pump operation was less postoperative morbidity; however, less complete revascularization introduced uncertainty about late results. A disadvantage of on-pump bypass was higher morbidity that seemed attributable to cardiopulmonary bypass.

Aged↗
PubMed2002

Mitral valve repair for degenerative disease.

Degenerative mitral valve disease is the most common cause of mitral regurgitation in North America. Using techniques developed by Carpentier and others, up to 90% of degenerative mitral valves can be repaired. These valves are characterized by annular dilatation and chordal rupture or elongation; chordal changes are mainly localized to the posterior leaflet. The most common repair technique for posterior leaflet prolapse is quadrangular resection. When the leaflet is >1.5 cm long, a sliding repair is added to reduce the risk of systolic anterior motion. Anterior leaflet prolapse is usually treated by transfer of chords from the posterior leaflet or adjacent areas of the anterior leaflet. Other useful techniques for correction of anterior leaflet prolapse are creation of artificial chords and the Alfieri edge-to-edge repair. Chordal shortening is rarely employed as it jeopardizes repair durability. Annuloplasty accompanies all repairs. A posterior annuloplasty provides results equivalent to those obtained with a circumferential annuloplasty. Flexible annuloplasty has theoretical advantages, but clinical benefits have not been shown. After mitral valve repair for degenerative disease, 10-year freedom from reoperation is 93%. Risk of reoperation is increased by anterior leaflet prolapse, chordal shortening, failure to use an annuloplasty, and lack of intraoperative echocardiography. In the ideal situation, when posterior leaflet resection is corrected by quadrangular resection with annuloplasty and the result is confirmed by intraoperative echocardiography, the 10-year durability is 98%.

Female↗
PubMedDate not supplied

Association of sternal wound infection with parasternal muscle sutures.

BACKGROUND: Sternal wound infection complicating open-heart surgery is a potentially devastating complication that has been associated with a number of risk factors. We recently consulted on three consecutive patients with this complication who had heavy nonabsorbable parasternal sutures placed in muscle tissue adjacent to the sternum. The aim of this report is to document our findings and caution that this technique to control bleeding from the parasternal intercostal muscles my increase risk of infection. METHODS: The pathology, surgical findings, and microbiology of these three cases are analyzed for similarity and possible cause of infection. RESULTS: By surgical observation and culture reports, each infection appeared to have originated at the site of nonabsorbable suture in devascularized parasternal muscle tissue. Sinus tracts could be probed to a similar site in each patient. CONCLUSION: Placement of sutures in the parasternal muscles where the sternal wires wrap around the bone leads to compression and necrosis of muscle tissue. We caution that this technique to control bleeding may cause a nidus of infection and increase the risk of deep sternal wound infection.

Adult↗
PubMedDate not supplied

In vitro performance of the novel coronary sinus AutoRetroPerfusion Cannula.

Myocardial salvage through coronary sinus intervention has been documented. The AutoRetroPerfusion Cannula is a novel device that is able to perfuse the coronary bed retrogradely through the coronary sinus with arterial blood generated from a peripheral artery with no need for a pump. The cannula consists of a distal end that, once secured in the coronary sinus, opens an umbrella-like membrane to create pressure in the coronary sinus, and at the same time has small channels directed backwards to the right atrium to provide pressure relief. The cannula is introduced from the axillary vein under local anesthesia and the proximal end, which consists of a graft, is anastomosed to the axillary artery to start autoperfusion once the distal end is secured in the coronary sinus and the occluding membrane is open. The AutoRetroPerfusion Cannula was tested in the in vitro mock loop under 50-120 mm Hg of proximal pressure and 50, 100, and 150 ml/min of total flow in the cannula. We were able to achieve the nominal design point of 40-80 mm Hg of distal pressure and 50-150 ml/min of distal flow by adjusting the number, diameter, and length of the small backwards channels.

Biomedical Engineering↗