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Biomedical subjects

G S Couper

Publications and source records attributed to G S Couper.

At least 19 recordsLinked to original sources
PubMed1997

Influence of inhaled nitric oxide on systemic flow and ventricular filling pressure in patients receiving mechanical circulatory assistance.

BACKGROUND: In patients with left ventricular (LV) dysfunction, inhaled nitric oxide (NO) decreases pulmonary vascular resistance (PVR) but causes a potentially clinically significant increase in left atrial pressure (LAP). This has led to the suggestion that inhaled NO may reach the coronary circulation and have a negative inotropic effect. This study tested an alternative hypothesis that LAP increases because of volume shifts to the pulmonary venous compartment caused by NO-induced selective pulmonary vasodilation. METHODS AND RESULTS: The Thermo Cardiosystems Heartmate is an LV assist device (LVAD) that can be set (by controlling pump rate) to deliver fixed or variable systemic blood flow. Eight patients (between 1 and 11 days after LVAD implantation) were administered inhaled NO (20 and 40 ppm for 10 minutes), and LAP, systemic flow, and pulmonary arterial pressure were measured in both fixed and variable pump flow modes. In both modes, inhaled NO lowered PVR (by 25 +/- 6% in the fixed mode, P < .001, and by 21 +/- 5% in the variable mode, P < .003). With fixed pump flow, LAP rose from 12.5 +/- 1.2 to 15.1 +/- 1.4 mm Hg (P < .008). In the variable flow mode, LAP did not increase and the assist device output rose from 5.3 +/- 0.3 to 5.7 +/- 0.3 L/min (P < .008). CONCLUSIONS: A selective reduction in PVR by inhaled NO can increase LAP if systemic flow cannot increase. These data support the hypothesis that with LV failure, inhaled NO increases LAP by increasing pulmonary venous volume and demonstrate that inhaled NO has beneficial hemodynamic effects in LVAD patients.

Administration, Inhalation↗
PubMed1996

Decreased myocardial oxygen consumption indices in dynamic cardiomyoplasty.

BACKGROUND: To investigate the theory of decreased myocardial oxygen consumption (MVo2) in dynamic cardiomyoplasty (DCM), previous studies have calculated indices of MVo2 in DCM. These previous studies, however, used left ventricular pressure in formulas that assumed the assumed the heart to be in its native state, with the reference pressure at the epicardium assumed to be atmospheric. In DCM, however, the reference pressure at the epicardium is no longer atmospheric but rather is the compressive pressure generated by the latissimus dorsi (LD). We therefore used the transmural myocardial pressure, Pt, to calculate indices of MVo2 in DCM. METHODS AND RESULTS: A half-ellipsoidal, fluid-filled balloon was interposed between the LD and myocardium in a balloon-mediated cardiomyoplasty procedure in five goats. With commonly used LD stimulation parameters, Pt was calculated as left ventricular pressure minus balloon luminal pressure. Using Pt, the transmural tension time index (TtTI) and transmural pressure volume area (PtVA) were calculated. In another series of four goats, LD stimulation parameters were optimized and the TtTI and PtVA recalculated. With standard LD stimulation parameters, the TtTI decreased by 48%, from 15.8 to 8.2 mm Hg.s, and the PtVA by 21%, from 775 to 612 mm Hg.mL, as the LD was stimulated to contract. When the optimized parameters were used, the TtTI decreased by 45%, from 11.2 to 6.2 mm Hg.s, and the PtVA by 33%, from 1984 to 1371 mm Hg.mL. CONCLUSIONS: Our results suggest that DCM with a fluid-filled balloon decreases MVo2 as the LD contracts and that LD stimulation parameters have a determining effect on this benefit.

Animals↗
PubMed1996

Predictors of atrial fibrillation after coronary artery surgery. Current trends and impact on hospital resources.

BACKGROUND: Atrial fibrillation (AF) after coronary artery bypass surgery (CABG) is the most common sustained arrhythmia. Its pathophysiology is unclear, and its prevention and management remain suboptimal. The aim of this prospective study was to determine the current incidence of AF, identify its clinical predictors, and examine its impact on resource utilization. METHODS AND RESULTS: Over a 12-month period ending July 31, 1994, a CABG procedure was performed on 570 consecutive patients (age range, 32 to 87 years; median age, 67 years; 232 [41%] were > or = 70 years; 175 [31%] were women; 173 [30%] were diabetics; 364 [65%] required nonelective surgery; 86 [15%] had had a prior CABG; and 86 [15%] had had prior percutaneous transluminal coronary angioplasty). AF occurred in 189 patients (33%). The median age for patients with AF was 71 years compared with 66 for patients without (P = .0001). Multivariate logistic regression analysis (odds ratio, +/- 95% CI, P value) was used to identify the following independent predictors of postoperative AF: increasing age (age 70 to 80 years [OR = 2; CI, 1.3 to 3; P = .002], age > 80 years [OR = 3; CI, 1.6 to 5.8; P = .0007]), male gender (OR = 1.7; CI, 1.1 to 2.7; P = .01), hypertension (OR = 1.6; CI, 1.0 to 2.3; P = .03), need for an intraoperative intraaortic balloon pump (OR = 3.5; CI, 1.2 to 10.9; P = .03), postoperative pneumonia (OR = 3.9; CI, 1.3 to 11.5; P = .01), ventilation for > 24 hours (OR = 2; CI, 1.3 to 3.2; P = .003), and return to the intensive care unit (OR = 3.2; CI, 1.1 to 8.8; P = .03). The mean length of hospital stay after surgery was 15.3 +/- 28.6 days for patients with AF compared with 9.3 +/- 19.6 days for patients without AF (P = .001). The adjusted length of hospital stay attributable to AF was 4.9 days, corresponding to > or = $10 055 in hospital charges. CONCLUSIONS: AF remains the most common complication after CABG and consequently is a drain on hospital resources. Concerted efforts to reduce the incidence of AF and the associated increased length of stay would result in substantial cost saving and decrease patient morbidity.

Adult↗
PubMed1996

Heart transplantation-associated perioperative ischemic myocardial injury. Morphological features and clinical significance.

BACKGROUND: The frequency and clinical significance of perioperative ischemic myocardial injury (PIMI) after heart transplantation and the diagnostic features distinguishing PIMI from rejection are not well defined. METHODS AND RESULTS: We evaluated PIMI in the first four weekly endomyocardial biopsies and/or autopsy myocardium from 140 consecutive orthotopic heart transplantation recipients (1984 to 1991) by grading the severity of coagulative myocyte necrosis (CMN) as absent, 0; mild-focal, 1; moderate-multifocal, 2; or severe-confluent, 3, and determining the evolution of morphological features of its healing. CMN (often with contraction bands) was noted in 124 patients (89%); 24 patients (17%) had grade 3 CMN, of which 4 died within 30 days of transplantation. Nevertheless, at 1 year after surgery, survival was similar in patients with and without severe injury. Increased cold ischemic time but neither donor age nor intensity of inotropic support correlated with more severe early ischemic injury. PIMI inflammation was characterized by a predominantly polymorphonuclear/histiocytic infiltrate that contained lymphocytes and plasma cells, expanding the interstitium but not encroaching upon and separable from adjacent viable myocytes. Histological features of PIMI developed and resolved more slowly than those of typical myocardial infarct necrosis in nonimmunosuppressed patients; at 4 weeks, CMN persisted in 20% of patients and residual healing in nearly half. Diagnostic rejection was observed concurrently with PIMI in 54 of 533 biopsies (10%). CONCLUSIONS: Diagnosed by conventional histological criteria, PIMI is prevalent early after heart transplantation and has a protracted healing phase that can mimic or coexist with rejection. Extensive PIMI has deleterious impact on short-term survival, but the long-term impact of PIMI remains to be established.

Adolescent↗
PubMed1996

Thigh ischemia complicating femoral vessel cannulation for cardiopulmonary bypass.

Compartment syndrome of the lower leg is an occasional complication of prolonged ischemia and reperfusion. Compartment syndrome of the thigh is a less well-recognized complication. We present 2 patients with compartment syndrome of the ipsilateral thigh after femoral arterial and venous cannulation for cardiopulmonary bypass. Early diagnosis and urgent decompressive fasciotomy may limit the extent of local tissue damage and subsequent myonephropathic syndrome.

Aged↗
PubMed1996

Current incidence and determinants of perioperative myocardial infarction in coronary artery surgery.

Increasingly, patients undergoing coronary artery bypass grafting (CABG) are elders, have had previous CABG, and have poor left ventricular function. To evaluate determinants of perioperative myocardial infarction (PMI) after isolated CABG, 499 consecutive patients were reviewed. Definite PMI (total peak creatine kinase [CK] > 700 U/L, creatine kinase MB [CK-MB] > 30 ng/ml, and new pathologic electrocardiographic Q waves) occurred in 25 patients (5.0%) and probable PMI (total peak CK > 700 U/L, CK-MB > 30 ng/ml, and a new wall-motion abnormality) occurred in 10 (2.0%) patients. According to multivariate logistic regression analysis, independent risk factors for definite or probable PMI (adds ratios; 95% confidence intervals) were emergency surgery (3.1; 1.1 to 8.4; p = 0.003), aortic cross-clamp time > 100 minutes (4.2; 1.6 to 11.2; p = 0.004), myocardial infarction in the preceding week (2.6; 1.0 to 6.4; p = 0.04), and previous revascularization (2.4; 1.1 to 5.2; p = 0.02). In conclusion, both preoperative and intraoperative factors influence the risk of PMI after CABG. Despite changes in the profile of patients undergoing CABG, the incidence of PMI in this tertiary center is comparable with that found in earlier series, probably because of improvements in surgical techniques and postoperative care.

Aged↗
PubMed1996

Reduced mortality and morbidity for ascending aortic aneurysm resection regardless of cause.

BACKGROUND: This study was done to answer the question, "What is the current risk of resection of ascending aortic aneurysms regardless of acuity or cause?" METHODS: One hundred fifteen consecutive patients who underwent ascending aortic aneurysm repair from January 1, 1990, to July 1, 1995, were retrospectively reviewed, excluding those with acute ascending aortic dissection. The mean age was 59 years; 55% were male. Concomitant procedures included coronary artery bypass in 23 (20%) and arch repair in 12 (10%). In group 1, 54 patients had replacement of the aortic valve, root, and ascending aorta with a valve-graft conduit using the "Bentall" technique, and of these 19 (35%) had Marfan's syndrome. In group II, 44 patients had separate aortic valve repair or replacement and supracoronary ascending aortic replacement. In group III, 17 patients had supracoronary ascending aortic replacement, without aortic valve operation. Operative techniques included frequent use of (1) intraoperative transesophageal echocardiography or epiaortic ultrasound scanning of the ascending and descending thoracic aorta to help guide arterial cannulation, avoid atherosclerotic embolization, and assess the repair; (2) antegrade and retrograde multidose cold blood cardioplegia for myocardial protection; (3) exclusion and button anastomotic techniques to ensure secure suture lines; (4) antifibrinolytic agents and collagen-impregnated aortic grafts to reduce bleeding; and (5) deep hypothermic circulatory arrest and the open distal anastomotic technique in patients with distal ascending and arch aortic disease. RESULTS: Operative mortality overall was 2/115 (1.7%). Mortality was 1/54 (1.8) in group I and 1/44 (2%) in group II, and there was no mortality in group III. The overall postoperative morbidity was 3% due to bleeding, 2% due to stroke, and 1% due to myocardial infarction. The length of stay in the past year has decreased to less than 7 days. CONCLUSIONS: The current risk for ascending aortic aneurysm repair is low (< 2%) whether or not the aortic root or valve also needs repair, regardless of the cause of the aneurysm.

Adult↗
PubMed1995

Determinants of early mortality and late survival in mitral valve endocarditis.

BACKGROUND: Infective mitral valve endocarditis continues to be a significant surgical challenge. The objective of this study was to examine our experience with mitral valve endocarditis surgery and identify determinants of early mortality and late survival. METHODS AND RESULTS: Over a 24-year period, mitral valve surgery was performed in 96 patients for infective mitral valve endocarditis. Patient age ranged from 20 to 78 years (median age, 52 years). There were 44 women (46%), and 48 of the 96 patients (50%) were in New York Heart Association functional class IV before surgery. Native valve endocarditis (NVE) and prosthetic valve endocarditis (PVE) were present in 72 patients (75%) and 24 patients (25%), respectively. Surgery during the active phase of endocarditis (AE) was required in 60 patients (62%) and during the healed phase (HE) in 36 (38%). The main indications for surgery in the AE group were congestive heart failure (60%), active sepsis (67%), peripheral emboli (47%), and acute renal failure (20%), and for the HE group the main indication was progressive congestive heart failure (69%). The overall operative mortality was 5.2%. Multivariate logistic regression analysis identified PVE (odds ratio [OR] 22.5; +/- 95% confidence interval, CI, 1.9 to 268; P = .014) and an associated procedure (OR 13.3; +/- 95% CI, 1.5 to 120; P = .021) to be independent predictors for early mortality. Follow-up was 97% complete, with a median of 3.5 years. Overall 5- and 10-year survivals were 83 +/- 4% and 63 +/- 8%, respectively. Multivariate analysis for late mortality identified PVE to be a significant predictor of late mortality (hazards ratio = 3.1, +/- 95% CI, 1.4 to 6.8, P = .006). There were no significant differences in long-term morbidity results among the various subsets of mitral valve endocarditis. CONCLUSIONS: Mitral valve surgery for infective endocarditis is a significant high-risk procedure for PVE and when combined with associated procedures. The activity of endocarditis does not appear to have any influence on early mortality or long-term survival.

Adult↗
PubMed1995

New technique measures decreased transmural myocardial pressure in cardiomyoplasty.

BACKGROUND: We introduce the use of a fluid-filled balloon, interposed between myocardium and latissimus dorsi (LD), as a new technique to measure transmural myocardial pressure in an acute goat model of dynamic cardiomyoplasty. METHODS: A half-ellipsoidal balloon, composed of polychloryl vinyl layers, was sutured to the atrioventricular groove in 5 goats, thereby completely enveloping both ventricles. Left LD dynamic cardiomyoplasty was then performed, anchoring the LD to the felt sewing skirt of the balloon so that the LD completely covered the balloon. Left ventricular pressure and balloon pressure were measured with the stimulator in the 1:2 mode as balloon volume was varied. RESULTS: Average transmural myocardial pressure, defined as left ventricular pressure minus balloon pressure, decreased from 34.4 mm Hg to 15.6 mm Hg during stimulator-on beats (p < 0.05). CONCLUSION: These results support the conclusion that dynamic cardiomyoplasty unloads the left ventricle by decreasing wall stress. Furthermore, transmural myocardial pressure decreased more when balloon volume was increased, implying that the LD sarcomere length has an effect on wall stress. A balloon may therefore allow optimization of LD sarcomere length and thus assisted cardiac performance.

Animals↗
PubMed1995

The effect of pathophysiology on the surgical treatment of ischemic mitral regurgitation: operative and late risks of repair versus replacement.

Operative correction of ischemic mitral regurgitation (IMR) is associated with high risk approach. The objective of this retrospective study was to examine the interaction between the various underlying pathophysiologic mechanisms, the operative procedure, and their influence on short- and long-term outcomes. Over a 10-year period starting January 1984, mitral valve repair or replacement was performed on 150 patients with IMR. The age range was 42-86, mean 67, years; 71 (47%) were females; 139 (93%) were in NYHA functional class III or IV; 23 (15%) were reoperations; and 30 (20%) were in atrial fibrillation. Functional IMR due to annular dilatation or restrictive leaflet motion was present in 106 (71%), and structural IMR due to ruptured chordae or papillary muscle in 44 (29%). Mitral valve repair was performed in 94 (63%) with an annuloplasty ring employed in 80 (85%) patients. Mitral valve replacement was performed in 56 (37%), with 40 (71%) receiving a bioprosthesis (32 Hancock and 8 Carpentier-Edwards valves) and 16 (29%) a St. Jude valve. Coronary artery bypass graft surgery was performed in 139 (93%) patients. The overall operative mortality (OM) was 14/150 (9.3%). The OM for repair was 9.5% compared to 8.9% for replacement (P = NS). There was higher OM in the elderly, particularly in the repair group (P = 0.053), and a trend towards reduced OM in the recent years of the study (P = NS). No predictors of OM were identified by multivariate logistic regression analysis. Long-term follow-up was 98% complete and ranged from 2-120, mean 31.2, months for a total of 935 patient-years. The overall 5-year survival rate was 71 +/- 6%, with 91 +/- 5% for the replacement group compared to 56% +/- 10% for the repair group (P = 0.01). The functional subset of IMR who had a repair had the worse long-term survival (43 +/- 13%) compared to the structural/repair (76 +/- 13%) and structural/replacement groups (89 +/- 8%), and 92 +/- 7% for the functional/replacement group ((P = 0.0049). Multivariate logistic regression analysis identified the functional/repair group (hazards ratio 4.4; +/- 95%, confidence interval 1.6, 11, (P = 0.0031); and earlier years of surgery (hazards ratio 4.7; +/- 95% confidence interval 1.021; (P = 0.046) to be predictors of worse long-term survival. These results suggest that, in IMR, the underlying responsible pathophysiologic mechanisms appear to be the major determinants of survival, rather than the choice of the operative procedure.

Adult↗
PubMed1995

Decreased adenylate cyclase activity and expression of Gs alpha in human myocardium after orthotopic cardiac transplantation.

We studied several aspects of guanine nucleotide-stimulated adenylate cyclase function in patients after orthotopic cardiac transplantation. In 28 patients, adenylate cyclase activity was measured in endomyocardial biopsy samples obtained just before and at monthly intervals after cardiac transplantation. In biopsies obtained > or = 6 months after transplantation, basal adenylate cyclase activity was decreased by 67% (n = 12; P < .05), GTP gamma S-stimulated adenylate cyclase activity was decreased by 78% (n = 12; P < .05), Mn+2+forskolin-stimulated adenylate cyclase activity was decreased by 80% (n = 8; P < .05), and Mn+2-stimulated adenylate cyclase activity (a measure of activity of the catalytic subunit of adenylate cyclase) was decreased by 83% (n = 8, P < .05). Western blot analysis demonstrated that 6 months after cardiac transplantation, the level of Gs alpha protein was decreased by 61 +/- 12% (n = 8; P < .001). There was no change in the level of Gi alpha as assessed by pertussis toxin-catalyzed ADP-ribosylation (n = 4; P = NS). With the use of the quantitative polymerase chain reaction, a 50 +/- 10% (n = 6; P < .001) reduction in the steady-state level of Gs alpha mRNA was observed. There was no change in the level of mRNA for Gi-3 alpha. Thus, after orthotopic cardiac transplantation in humans, guanine nucleotide-stimulated adenylate cyclase activity is decreased in parallel with decreased levels of Gs alpha protein and mRNA.

Adenylyl Cyclases↗
PubMed1994

Early cardiac allograft failure after orthotopic heart transplantation.

Early cardiac graft failure has been reported to occur in 4-25% of patients undergoing orthotopic heart transplantation. To further elucidate the characteristics and prognosis of patients with graft failure, we retrospectively identified 10 patients from a series of 212 consecutive recipients with catastrophic graft dysfunction in the absence of acute cellular rejection, right ventricular failure secondary to pulmonary hypertension and technical factors. We present a case report and the experience from one transplant center, a review of the literature and possible strategies for the management of early graft failure. Mean onset of graft failure was 6.5 days (range intraoperative to 23 days). Multivariable analysis revealed a longer total ischemic time in patients with early graft dysfunction (200 +/- 14 vs. 166 +/- 4 min). No episodes of hyperacute rejection were observed. Pathologic changes noted on biopsy or autopsy included ischemia in 9 and vascular rejection in 1. The mortality at 60 days was 50%. Early use of aggressive mechanical and pharmacological support is described and appears to be important for graft salvage.

Adult↗
PubMed1994

Single-clamp technique: an important adjunct to myocardial and cerebral protection in coronary operations.

To determine the myocardial and cerebral protective properties of the single cross-clamp (group I; n = 160) versus the partial occluding clamp (group II; n = 150) technique for construction of the proximal anastomoses, a retrospective analysis of 310 patients operated on by the same surgeon was performed. Group I patients were older (median age, 70 versus 64 years; p < or = 0.0001), with 83 (52%), versus 41 (27%) in group II, 70 years and older (p < or = 0.0001). More group I patients were in New York Heart Association functional class IV (42 [26%] versus 22 [15%]; p = 0.008); more required preoperative balloon counterpulsation (35 [22%] versus 16 [11%]; p = 0.006); and more required emergent operation (20 [13%] versus 3 [2%]; p < or = 0.0001). Antegrade crystalloid cardioplegia was used in both groups. The median cross-clamp time was 58 minutes for group I versus 44 minutes for group II (p < or = 0.0001). However, there was no significant difference between the two groups in terms of the number of bypass grafts, the use of the mammary artery, or the bypass time. The operative mortality was 2.5% (n = 4) for group I versus 5.3% (n = 8) for group II (p = 0.16), and the perioperative myocardial infarction/low cardiac output state was seen in 6 patients (3.8%) in group I versus 18 patients (12%) in group II (p = 0.006). The median creatine kinase MB release was 13 U/L for group I versus 19 U/L for group II (p = 0.0029).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Pericardial effusions after cardiac transplantation.

OBJECTIVES: The aim of this study was to determine the etiologic factors in the formation of significant pericardial effusion after orthotopic heart transplantation and to determine the association of pericardial effusion with survival. BACKGROUND: The formation of pericardial effusions has been well described after orthotopic heart transplantation, but the risk factors for development of effusions remain unclear. Rejection and cyclosporine have been cited as possible causes, but anatomic factors have not been studied. METHODS: We conducted a retrospective review of medical records and echocardiograms of 203 consecutive patients at one center, including ischemic time, incidence and severity of rejection, weight difference between donor and recipient and previous cardiac surgical history. Multivariate analysis was performed, and actuarial survival rate curves were calculated according to the Kaplan-Meier method. RESULTS: Eighteen (8.9%) of 203 transplant recipients developed moderate to large pericardial effusions. Forty-four percent of patients required pericardiocentesis, and 28% subsequently required pericardiectomy for management of the effusions. Multivariate analysis identified the presence of a positive weight difference between recipient and donor (recipient weight > donor weight) and the lack of previous median sternotomy as the most powerful predictors of effusion formation. No significant association was found with rejection. There was no difference in actuarial survival rate between patients with and without effusions. CONCLUSIONS: A positive mismatch in weight between recipient and donor and the absence of previous cardiac surgery are associated with the formation of significant pericardial effusions. Closer monitoring of these patients at risk may be warranted.

Adolescent↗
PubMed1994

Aortic valve endocarditis. Determinants of early survival and late morbidity.

BACKGROUND: Aortic valve surgery for endocarditis remains a high-risk procedure. The objective of this study was to analyze the interaction between the various subsets of endocarditis (native, prosthetic, healed, and active), timing of surgery, and their influence on early and late outcomes. METHODS AND RESULTS: During a 20-year period starting January 1972, 200 patients underwent aortic valve replacement for infective endocarditis (age range, 13 to 88 years; median, 53 years). There were 51 (26%) females, and 109 (55%) were in New York Heart Association functional class IV before surgery. Native valve endocarditis (NVE) and prosthetic valve endocarditis (PVE) were present in 132 (66%) and 68 (34%) patients, respectively. Surgery was required in 120 (60%) during the active phase (AE) and 80 (40%) during the healed phase (HE) of endocarditis. The main indication for surgery in the healed group was progressive congestive heart failure. The indications for the active group were congestive heart failure (68%), continuing active sepsis (70%), echocardiographic vegetation (28%), peripheral emboli (30%), and arrhythmias (13%). Streptococcal infections predominated in NVE, staphylococcal in PVE and AE; culture-negative endocarditis predominated in the healed group. Isolated aortic valve surgery was performed in 68% of the patients, and concomitant procedures (32%) included mitral valve and coronary bypass procedures. The overall operative mortality (OM) was 12.5%. The OM was 7.5% and 22% for NVE and PVE, respectively (P = .004), and 7% for HE versus 15% for AE (P = .06). The OM for early PVE was 33% versus 18% for late PVE (P < .05). Multivariate logistic regression analysis identified PVE and New York Heart Association functional class IV to be independent predictors for early death. Recurrent endocarditis occurred 26 times in 24 patients (11 early, 13 late), with three operative deaths in the early group, all due to residual staphylococcal infections. Freedom from recurrent endocarditis was significantly different between HE (96 +/- 3% and 86 +/- 6% at 5 and 10 years, respectively) and AE (89 +/- 3% and 83 +/- 4%, respectively (P = .02). Long-term survival for discharged patients was 81 +/- 3% and 63 +/- 5% at 5 and 10 years, respectively, with no significant difference between NVE, PVE, AE, and HE. CONCLUSIONS: These data suggest that for active endocarditis, surgery should be delayed to achieve a healed status provided there is no pressing need for immediate surgery. Patients with staphylococcal endocarditis, particularly on a prosthesis, should be operated on sooner and should be covered with antibiotics for an extended period to prevent recurrent PVE. This study stresses the need for aggressive antibiotic prophylaxis, particularly in the presence of a prosthesis.

Aortic Valve↗