Concomitant Valve Replacement and Coronary Artery Bypass Grafting Surgery: Lessons from the Past, Guidance for the Future? A Mortality Analysis in 294 Patients.

OBJECTIVE: The aims of this study were to analyze parameters influencing early and late mortality after concomitant valve replacement and coronary artery bypass grafting surgery, using early and long-term information from an institutionally available data registry, and to discuss the results in relation to the current treatment strategies and perspectives. METHODS: The study population consisted of 294 patients after combined valve replacement with mechanical prosthesis and CABG surgery. RESULTS: There were 201 men (68.4%) and 93 women (31.6%). Concurrent to the coronary artery bypass grafting, 238 patients (80.9%) underwent aortic-, 46 patients (15.6%) mitral- and 10 patients (3.4%) doublevalve replacement. Cumulative duration of follow up was 1007 patient-years (py) with a maximum of 94 months and was completed in 92.2% (271 cases). Overall hospital mortality (30 days) rate was 6.5% (n = 19). It was significantly higher in patients of female gender, older than 70 y, in those suffering preoperative myocardial infarction, presenting with an additive EuroScore > 8 and being hemodynamically unstable after the operation. Cumulative survival rate at 7.6 y was 78.6%. Determinants of prolonged survival were male gender, age at operation < 70 y, preoperative sinus rhythm, normal renal function, additive EuroScore < 8 and the use of internal thoracic artery for grafting. Subsequent multivariate analysis revealed preoperative atrial fibrillation (HR: 2.1, 95% CI: 0.82-5.44, p: 0.01) and risk group of ES > 8 (HR: 3.63, 95% CI: 1.45-9.07, p < 0.01) as independent predictors for lower long-term survival. CONCLUSIONS: Hospital mortality (30 d) was nearly 2.5-fold higher in female and/or older than 70 y patients. Preoperative atrial fibrillation and/ or a calculated ES > 8 were independent predisposing factors of late mortality for combined VR and CABG surgery. Tailoring the approach, with the employment of the newest techniques and hybrid procedures, to the individual patient clinical profile enables favorable outcomes for concomitant valvular disease and CAD, especially in high-risk patients.

Surgical management of infective endocarditis: early and long-term mortality analysis. single-center experience and brief literature review.

INTRODUCTION: In this study we evaluated factors that affect the early and long-term postoperative outcomes of patients with infective endocarditis. METHODS: We retrospectively reviewed 94 patients (68 male, 26 female, mean age 58.3 ± 13.1 years, range 20-85 years) with proven infective native (n=85) or prosthetic valve (n=9) endocarditis who underwent heart valve surgery between September 1997 and December 2007. Fifty-four patients (57.4%) underwent aortic, 28 (29.8%) mitral, 3 (3.2%) tricuspid, 8 (8.5%) double, and one patient (1%) triple valve surgery. In 75.5% of the procedures we implanted mechanical valves, in 13.8% biological prostheses, and 10.7% were reconstructive or other procedures. Midterm follow up was 100% complete with a cumulative duration of 545 patient-years (maximum 12 years). RESULTS: Overall hospital mortality (30 days) was 8.5% (n=8). Causes of early mortality were low cardiac output syndrome in 2 cases, sepsis with multiple organ failure in 5 cases, and intracerebral bleeding in one patient. Development of postoperative low cardiac output syndrome (p=0.01) was identified as an independent predictor of early mortality. Overall late mortality was 25.6% (n=22) with a cumulative rate of 4.03% per patient-year. Causes of late death were predominantly of extracardiac origin. Kaplan-Meier survival analysis revealed a cumulative survival rate at 12 years of 57.2%. Cox regression analysis identified diabetes mellitus (p=0.016) and postoperative low cardiac output syndrome (p=0.03) as independent late mortality factors. CONCLUSIONS: Heart valve surgery in patients with infective endocarditis is associated with increased but acceptable early and long-term mortality. The mid-term prognosis is similar to that of patients undergoing elective valve replacement surgery.

Performance of EuroSCORE II compared to EuroSCORE I in predicting operative and mid-term mortality of patients from a single center after combined coronary artery bypass grafting and aortic valve replacement.

OBJECTIVE: The performance comparison of the recently introduced European System for Cardiac Operative Risk Evaluation II in predicting operative as well as mid-term mortality, with its previous version in patients after combined aortic valve replacement and coronary artery bypass grafting surgery. METHODS: This retrospective analysis included 216 patients operated on at one institution from 01/1999 to 12/2005. Accuracy and calibration of EuroSCORE I and II were assessed by plotting the areas under the receiver operator curves and comparing observed and predicted mortalities. RESULTS: EuroSCORE II showed, regarding early mortality, a slightly higher discriminatory accuracy with an area under the receiver operator curve of 0.77, while additive and logistic EuroSCORE I areas were 0.749, 0.75, respectively. The highest specificity and sensitivity level was approached for EuroSCORE II at a predicted mortality of 4.4 %. Receiver operator curves concerning mid-term mortality revealed areas for additive, logistic EuroSCORE and EuroSCORE II of 0.745, 0.739 and 0.718 with the highest accuracy levels at predicted mortalities of 6.5, 6.48 and 3.88 %, respectively. Mean predicted mortalities by logistic EuroSCORE and EuroSCORE II were 8.35 and 3.99 %, respectively, while overall observed operative mortality was 6.3 %. In "high-risk" patients (EuroSCORE > 13), EuroSCORE II underestimated early and mid-term outcomes. CONCLUSIONS: Regarding operative mortality, EuroSCORE II showed in this study a slightly higher discriminatory accuracy than EuroSCORE I. There were no significant differences in the calibration of the two model versions in "low-" and "moderate-risk" patients regarding early as well as mid-term mortality. Analyses in larger patient populations will contribute to further model improvement.

Early and late outcomes of cardiac operations in patients with cirrhosis: a retrospective survival-rate analysis of 47 patients over 8 years.

OBJECTIVES: Patients with liver cirrhosis are considered as high-risk population for cardiac surgery. The aim of this study was to review mortality and mid-term outcome of patients with liver cirrhosis requiring coronary artery bypass graft (CABG), valve replacement, or combined procedures. METHODS: Between July 1997 and December 2006, 47 patients (mean age 65.4 ± 11.7 years) with liver cirrhosis were operated for CABG (21 patients), aortic valve replacement /mitral valve replacement (14 patients), CABG/VR (9 patients) or aortic dissection/tumorexstirpation (3 patients) (group I). Thirty-three patients were classified as Child-Pugh class A (subgroup A), 14 patients as Child-Pugh class B cirrhosis (subgroup B). Postoperative complications/mortality were analyzed retrospectively and compared with a propensity-score pair-matched control group of 47 patients (group II). Follow-up ranged from 0.1 to 11.5 years (mean 3.9 ± 0.25 years) and was complete for 100%. RESULTS: Necessity of blood products was higher in group I (red cells, fresh frozen plama, platelets; P < 0.01). Chest-tube output (group I 1113 ± 857 vs. group II 849 ± 521; P = 0.15) and re-exploration rate (8.5 vs. 0%; P = 0.11) were slightly accelerated. Ventilation time and ICU-stay was prolonged (P < 0.015). Thirty-day mortality showed 19.1% (group I) versus 8.5% (group II) (P < 0.01), 6.1% (subgroup A) versus 50% (subgroup B) (P < 0.01). Operative risk in subgroup A was not significantly increased compared with control group (P = 0.68). In Child-B operative risk was 15.5-fold higher than in Child-A cirrhosis (P < 0.001). Postcardiotomy syndrome and pleurisy were more frequent in the cirrhosis group (4/47 vs. 0/47; P = 0.11). Actuarial survival after 3, 5 and 8 years was: group I 78.6, 75.6, and 70.2% versus group II 89.1, 85.7, and 85.7% (P = 0.08). Subgroup survival analysis was: group A 90.7, 86.6, and 78.5% versus group B 50, 50, and 50% (P < 0.01). CONCLUSION: Cardiac surgery can be performed safely in patients with Child-Pugh class A and selected patients with Child-Pugh class B cirrhosis. Mid-term survival-rates within 8 years were not significantly different compared with a propensity-score pair-matched control group without cirrhosis.

Pericytes in the macrovascular intima: possible physiological and pathogenetic impact.

The frequently observed de-endothelialization of venous coronary bypass grafts prepared using standard methods exposes subendothelial prothrombotic cells to blood components, thus endangering patients by inducing acute thromboembolic infarction or long-term proliferative stenosis. Our aim was to gain deeper histological and physiological insight into these relations. An intricate network of subendothelial cells, characterized by histological features specific for true pericytes, was detected even in healthy vessels and forms, coupled to the luminal endothelium, a second leaflet of the macrovascular intima. These cells, and particularly those in the venous intima, express enormous concentrations of tissue factor and can recruit additional amounts of up to the 25-fold concentration within 1 h during preincubation with serum (intimal pericytes of venous origin activate 30.71 +/- 4.07 pmol coagulation factor x.min(-1).10(-6) cells; n = 15). Moreover, decoupled from the endothelium, they proliferate rapidly (generation time, 15 +/- 2.1 h, n = 8). Central regions of atherosclerotic plaques, as well as of those of restenosed areas of coronary vein grafts, consist almost completely of these cells. In stark contrast with the prothrombogenicity of the intimal pericytes, intact luminal endothelium recruits high concentrations of thrombomodulin (CD 141) specifically within its intercellular junctions, activates Protein C rapidly (42 +/- 5.1 pmol/min.10(6) venous endothelial cells at thrombin saturation; n = 15), can thus actively prevent coagulatory processes, and never expresses histologically detectable and functionally active tissue factor. Given this strongly prothrombotic potential of the intimal pericytes and their overshooting growth behavior in endothelium-denuded vascular regions, they may play important roles in the development of atherosclerosis, thrombosis, and saphenous vein graft disease.

Extensive deendothelialization and thrombogenicity in routinely prepared vein grafts for coronary bypass operations: facts and remedy.

The objective of this study was to gain deeper insight into the early reasons for saphenous vein graft disease and to find a practical approach to obviate it. Intraoperative storage of freshly explanted venous grafts (45 min, 20 degrees C; n=25 in each case) in saline, saline + 5% albumin, or HTK-solution and also in heparinized autologous blood was poorly tolerated by the endothelium. Large endothelial areas (mostly >75% of total surface) were detached already during brief non-pulsatile flushing just before the transplantation. Contact of deendothelialized areas in graft remnants with defined mixtures of coagulation factors or blood (n=11-17) caused rapid coagulatory processes via expression of tissue factor and assembly of prothrombinase in the subendothelium. Attached platelets and leukocytes accelerated the procoagulatory processes further, and endothelium-dependent anticoagulatory activities were significantly abolished. During pulsatile arterial flow, the resulting blood clots exacerbated the damage of the intima markedly, because they were flushed away tearing off further endothelium. In contrast, storage of venous grafts in a plasma preparation freed from isoagglutinins and coagulation factors preserved the endothelium, which resisted arterial flow and revealed anticoagulatory activity in the presence of antithrombin III and/or protein C. We conclude that gentle preparation and preservation of the vascular endothelium with a suitable storage solution during bypass surgery is a decisive first step to obviate saphenous vein graft disease.

Sorin Bicarbon bileaflet valve: a 9.8-year experience. Clinical performance of the prosthesis after heart valve replacement in 587 patients.

OBJECTIVES: To determine early and mid-term clinical performance of the Sorin Bicarbon bileaflet prosthesis. METHODS: Between January 1993 and October 2000, 1092 patients received at least one Sorin Bicarbon prosthesis. Six hundred and fourteen of those fulfilled the inclusion criteria and were contacted by mail and/or telephone interview. Five hundred and eighty-seven (95.6%) patients aged 16.2-85.9 years (mean 61.5 years), 368 males and 219 females, were available for clinical evaluation. Four hundred and fifteen patients underwent aortic--(AVR) (70.7%), 122 mitral--(MVR) (20.8%), 50 double valve replacement (DVR) (8.5%). 86.4% of the patients were in NYHA functional class III or IV. Cumulative duration of follow-up is 2474 patient-years (py) with a maximum of 9.8 years. RESULTS: Overall hospital mortality (30 days) rate was 4.2% (n=26). The early mortality rate was significantly higher in females and patients older than 70 years (P<0.05). Valve related early deaths were not documented. There were 49 late deaths (8.3%). Overall late mortality was 1.98%/patient-years. Cumulative survival rate at 9.8 years was for AVR, MVR and DVR, 80.1, 95.1 and 76.4, respectively. Multivariable logistic analysis identified high age at operation (>or=70 years) as an independent mortality risk factor (P=0.03). Valve related complications were thromboembolism: 1.33%/patient-years (n=34), anticoagulant related hemorrhage: 1.21%/patient-years (n=30), bacterial endocarditis: 0.16%/patient-years (n=4), reoperation: 0.69%/patient-years (n=17), paravalvular leak: 0.69%/patient-years (n=17). No structural dysfunction of the prosthesis has been reported. Actuarial freedom from complications at 9.8 years was: thromboembolism 86.7%, major hemorrhage 92.3%, prosthetic valve endocarditis 99.1% and reoperation 95.8%. CONCLUSIONS: Sorin Bicarbon prosthesis provides excellent clinical results and mid-term survival with very low complication rates comparable with those of other bileaflet prostheses currently in use.

Quality of internal thoracic artery grafts after mediastinal irradiation.

BACKGROUND: With the increase of patients of advanced age requiring coronary artery bypass grafting (CABG), the number of those with previous mastectomy and irradiation of the chest increases proportionally. The question of whether mediastinal irradiation leads to relevant internal thoracic artery (ITA) graft damage remains unclear. The aim of the present study was to proof the quality of ITAs and to evaluate the early clinical outcome after using one or both ITAs in this specific population. METHODS: One hundred twenty-five patients (group A) with previous mastectomy or Hodgkin/non-Hodgkin disease and mediastinal irradiation operated on between January 1993 and September 2006 underwent CABG (n = 88) or CABG plus valve replacement (n = 37). Sixty-two patients received bilateral, 43 received unilateral ITAs, and 20 patients received veins. Postoperative complications and mortality were analyzed and compared with a propensity score pair-matched control group of 125 patients receiving CABG or CABG plus valve replacement within the same period (group B). A histomorphologic investigation was performed in 133 irradiated distal ITA segments and compared with a control group of 133 nonirradiated ITAs. RESULTS: Thirty-day mortality revealed 3.2% in group A versus 5.6% in group B. Sternal instabilities were more frequent in group A (3.2%) than in group B (0%). Mediastinitis occurred in 1.6% (group A) versus 1.6% (group B). Histomorphologic investigations did not identify any severe irradiation induced fibrosis or damage of ITA grafts. CONCLUSIONS: From the histologic point of view, there is no need for restrictions in use of ITA conduits after mediastinal irradiation. Compared with a control group, cardiac surgery was associated with a slightly enhanced incidence of sternal instabilities.

Determinants of ascending aortic dimensions after aortic valve replacement with a stented bioprosthesis.

BACKGROUND AND AIM OF THE STUDY: Concomitant replacement of the mildly dilated ascending aorta during aortic valve replacement (AVR) is controversial because progress of aortic dilatation is uncertain after elimination of the valvular lesion. The study aim was to determine factors influencing the aortic dimensions, to analyze their clinical impact, and to identify criteria for concomitant surgery on the aorta. METHODS: Between February 1994 and May 1999, 100 patients with tricuspid aortic valve disease received the stented porcine Mosaic prosthesis within a FDA approval study. Follow up (mean 4.8 years; range: 0.1-8.8 years; total 483.4 patient-years) included documentation of adverse events and transthoracic echocardiography with measurements of the aortic sinus, sinotubular junction, and ascending aorta. RESULTS: Baseline aortic dimensions were dependent on gender and body surface area, but independent of the type and extent of valvular lesion, patient age, and atherosclerotic risk factors. Larger baseline aortic diameters were associated with smaller postoperative annual aortic expansion rates (r = -0.47, p <0.001). In patients with baseline aortic dilatation > or =40 mm (10.2%; mean 42.5+/-2.6 mm), aortic diameter decreased during follow up (p = 0.032; expansion rate -1.9+/-2.0 mm/year). Baseline aortic dilatation did not influence postoperative morbidity and mortality. Prosthetic regurgitation was associated with increases in aortic diameter (p <0.001). Survival was reduced in patients with aortic expansion rates >3.6 mm/year (0.0% versus 68.2+/-9.7%; p <0.001). CONCLUSION: AVR without concomitant surgery on the aorta in patients with mild aortic dilatation is feasible, as aortic diameters were decreased after removal of the diseased valve. The aortic expansion rate had a strong prognostic importance, even on aortic diameters, which are considered to be within normal ranges.

The Mosaic bioprosthesis in the aortic position: seven years' results.

BACKGROUND AND AIM OF THE STUDY: The Mosaic bioprosthesis is a stented porcine aortic valve, which combines glutaraldehyde fixation with zero-pressure and root-pressure techniques and anti-mineralization treatment with amino-oleic acid for improved hemodynamics and tissue durability. The study aim was to collect intermediate-term data of the Mosaic bioprosthesis in the aortic position, the first device having been implanted in February 1994 at the authors' institution. METHODS: A total of 100 patients (49 females, 51 males) underwent aortic valve replacement with the Mosaic bioprosthesis between February 1994 and May 1999. Mean age at implant was 73.4 +/- 7.3 years. Concomitant procedures were performed in 40.0% of cases. Patients were followed up within 30 days postoperatively, after six months, and at annual intervals thereafter. Mean follow up was 3.8 years (range: 0.1-7.1 years); total follow up was 383.1 patient-years (pt-yr) and 100% complete. RESULTS: Early mortality (< or = 30 days) was 3.0%; late mortality was 4.6%/pt-yr, including a valve-related mortality of 0.6%/pt-yr. Freedom from event at seven years was 96.8 +/- 1.8% for thromboembolic events, 97.2 +/- 2.0% for thrombosed bioprosthesis, 96.6 +/- 2.6% for structural valve deterioration, 98.2 +/- 1.8% for nonstructural dysfunction, 95.9 +/- 2.0% for anti-thromboembolic hemorrhage, 98.9 +/- 1.1% for endocarditis, and 93.9 +/- 3.2% for reoperation/explant. After one year, the mean systolic pressure gradient was 15.3 +/- 6.7, 14.5 +/- 5.7, 12.7 +/- 4.1 and 12.9 +/- 4.8 mmHg for 21, 23, 25 and 27 mm valves respectively; the effective orifice area (EOA) was 1.4 +/- 0.4, 1.7 +/- 0.4, 1.8 +/- 0.4 and 2.6 +/- 0.4 cm2 for 21, 23, 25 and 27 mm valves respectively; and the EOA index was 0.8 +/- 0.3, 0.9 +/- 0.2, 0.9 +/- 0.2 and 1.3 +/- 0.1 cm2/m2 respectively. The mean left ventricular mass index was decreased significantly, from 159.7 +/- 56.8 g/m2 to 137.3 +/- 40.8 g/m2, for all valve sizes after one year. CONCLUSION: Clinical and hemodynamic performance of the Mosaic bioprosthesis was highly satisfactory during the first seven years after clinical introduction.

Left ventricular mass regression after aortic valve replacement with the mosaic bioprosthesis.

BACKGROUND AND AIMS OF THE STUDY: The study aim was to evaluate the hemodynamic performance and extent of left ventricular (LV) mass regression after aortic valve replacement (AVR) with the Mosaic bioprosthesis within the first postoperative year. METHODS: Between 1994 and 1999, 366 patients (203 males, 163 females) underwent AVR with the Mosaic bioprosthesis at five centers in Europe. Mean age at implant was 71.1 years (range: 34.5-86.8 years). LV mass assessment and hemodynamic evaluation were performed using transthoracic echocardiography within six days postoperatively, after six months, and at annual intervals thereafter. RESULTS: LV mass index decreased significantly in patients with valve sizes 21 to 27 mm, from 184.4+/-56.2 g/m2 postoperatively to 157.3+/-45.5 g/m2 after one year (14.7% decrease). The 19-mm valve group did not show significant LV mass index reduction (from 210.4+/-39.4 to 195.0+/-59.4 g/m2; 7.3%). Patients with significant LV mass index regression had survival benefits after seven years. Mean pressure gradients after one year were 16.0+/-4.3, 14.2+/-5.4, 12.8+/-5.3, 11.1+/-4.0 and 10.5+/-3.7 mmHg for 19, 21, 23, 25 and 27 mm valves, respectively. CONCLUSION: Implantation of the Mosaic bioprosthesis resulted in a significant regression of LV mass for the valves sizes 21 to 27 mm, corresponding to very low pressure gradients for a stented bioprosthesis.

European experience with the Mosaic bioprosthesis.

OBJECTIVE: The purpose of this study was to prospectively evaluate the clinical and hemodynamic performance of the Mosaic bioprosthesis (Medtronic, Inc, Minneapolis, Minn). METHODS: The stented porcine bioprosthesis combines the amino-oleic acid antimineralization treatment and the zero-pressure differential fixation technique for improved tissue durability. From February 1994 to May 1999, a total of 561 patients underwent valve replacement with the Mosaic bioprosthesis at 5 centers in Europe: 461 in the aortic and 100 in the mitral position. There were 261 women and 300 men; mean age at implantation was 70 years (range, 23-89 years). Mean follow-up was 2.9 years (range, 0-6.2 years), with a total follow-up of 1710.1 patient-years. RESULTS: Postoperative mortality was 4.2% per patient-year, including a valve-related mortality of 0.4% per patient-year. The freedom from event rates in the aortic position at 5 years and in the mitral position at 4 years were, respectively, 96.6% +/- 1.1% and 94.9% +/- 3.3% for primary thromboembolism, 96.4% +/- 5.0% and 87.1% +/- 4.8% for antithromboembolic-related hemorrhage, 99.1% +/- 0.5% and 100% for thrombosed prosthesis, 98.8% +/- 1.2% and 100% for structural valve deterioration, 98.8% +/- 0.7% and 100% for nonstructural dysfunction, 98.4% +/- 0.6% and 94.4% +/- 3.8% for endocarditis, and 95.4% +/- 1.6% and 95.3% +/- 3.7% for explant and reoperation. Mean pressure gradient values at 5 years ranged from 7.5 to 15.9 mm Hg in the aortic position and at 4 years from 2.0 to 6.9 mm Hg in the mitral position across all valve sizes. CONCLUSIONS: Clinical and hemodynamic performance of the Mosaic bioprosthesis were very satisfactory during the first 6 years after clinical introduction.