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.

14-Year Results of Bilateral versus Single Internal Thoracic Artery Grafts for Left-Sided Myocardial Revascularization in Young Diabetic Patients

Objectives Despite encouraging late outcomes, the use of bilateral internal thoracic artery (BITA) grafting for myocardial revascularization in diabetic patients remains controversial because of an increased risk of sternal wound complications. In the present study, early- and long-term outcomes of the use of left-sided BITA versus single internal thoracic artery (SITA) grafting in young (< 65 years of age) diabetic patients were reviewed retrospectively.

Methods A total of 250 propensity score pair-matched diabetic patients, operated on between February 2000 and December 2011, receiving either BITA (n = 125) or SITA (n = 125) grafting were analyzed retrospectively. In each group, 104 patients were males, and mean age was 60.1 ± 5.3 years. Follow-up was 2.1 to 14.8 years (mean, 9.3 ± 3.5 years) and complete for 100%.

Results Incidence of deep sternal wound infection was 2.4 versus 3.2% (p = 0.722). Rethoracotomy due to bleeding occurred in 4.8 versus 3.2% (p = 0.608). The 5-, 10-, and 14-year estimates of survival were 93.4, 76.6, and 67.5% (BITA) versus 89.5, 81.5, and 32.8% (SITA); p = 0.288. Freedom from reangiography/intervention (60.5 vs. 63.9%) during follow-up was comparable (p = 0.507) as well as infarction rate (93.8 vs. 95.1%, p = 0.833) and redoes (p = 0.672, exclusively valve surgery) were comparable. Freedom from thromboembolic or cerebrovascular events did not show any significant differences (94.0 vs. 94.0%, p = 0.78). Multivariate analysis identified poor ejection fraction as predictor for decreased long-term survival. Neither age nor gender or urgency had an influence on long-term mortality.

Conclusion Left-sided BITA grafting may be performed routinely even in diabetic patients without increased incidence of postoperative wound-healing complications. Survival rates after 5, 10, and 14 years were comparable for BITA and SITA grafting.

Applying the Gender Lens to Risk Factors and Outcome after Adult Cardiac Surgery

Background

Applying the gender lens to risk factors and outcome after adult cardiac surgery is of major clinical interest, as the inclusion of sex and gender in research design and analysis may guarantee more comprehensive cardiovascular science and may consecutively result in a more effective surgical treatment as well as cost savings in cardiac surgery.

Methods

We have reviewed classical cardiovascular risk factors (diabetes, arterial hypertension, hyperlipidemia, smoking) according to a gender-based approach. Furthermore, we have examined comorbidities such as depression, renal insufficiency, and hormonal influences in regard to gender. Gender-sensitive economic aspects have been evaluated, surgical outcome has been analyzed, and cardiovascular research has been considered from a gender perspective.

Results

The influence of typical risk factors and outcome after cardiac surgery has been evaluated from a gender perspective, and the gender-specific distribution of these risk factors is reported on. The named comorbidities are listed. Economic aspects demonstrated a gender gap. Outcome after coronary and valvular surgeries as well as after heart transplantation are displayed in this regard. Results after postoperative use of intra-aortic balloon pump are shown. Gender-related aspects of clinical and biomedical cardiosurgical research are reported.

Conclusions

Female gender has become an independent risk factor of survival after the majority of cardiosurgical procedures. Severely impaired left ventricular ejection fraction independently predicts survival in men, whereas age does in females.

Does Bilateral ITA Grafting Increase Perioperative Complications? Outcome of 6,476 Patients with Bilateral versus 5,020 Patients with Single ITA Bypass

OBJECTIVES

 Despite the superior patency of internal thoracic artery (ITA) grafting compared with saphenous veins, frequency of bilateral ITA (BITA) grafting in Europe is still approximately 10%. The aim of the present study was to compare the early outcome of patients receiving either BITA or single ITA (SITA) grafting.

METHODS

 A total of 11,496 patients with isolated coronary artery bypass grafting (CABG), operated between January 1996 and December 2012, were analyzed retrospectively; 0.6476 patients (mean age 65.2 years, 81.3% males) received BITA and 5,020 patients (mean age 66.6 years, 76.7% males) SITA grafting. Mean body mass index (BMI) was 27.2 versus 27.4, p = 0.017. Incidence of diabetes was 28.9 versus 28.4%, p = 0.08. Ejection fraction (EF) > 50 was 71.3% (BITA) versus 66.3% (SITA), p < 0.001. Elective operations were performed in 88.4% (BITA) versus 83.3% (SITA), and urgent/emergent surgery was necessary in 11.6% (BITA) versus 16.7% (SITA), p < 0.001.

RESULTS

 Number of grafts was 3.76 (BITA) versus 3.06, p < 0.001. Duration of surgery (194.4 vs. 180.4 minutes) as well as X-clamp time (60.4 vs. 51.7 minutes) was prolonged for BITA, p < 0.001. Perioperative infarction rate revealed 3.2% (BITA) versus 3.6%, p = 0.54. Frequency of rethoracotomy due to bleeding was higher in the BITA group (3.8 vs. 2.1%), p < 0.001. Sternal instabilities occurred in 2.3% (BITA) versus 2.2%, p = 0.749. Duration of mechanical ventilation < 12 hours was 74.6 versus 77.1%, p = 0.09 and duration of in-hospital stay was 10.5 versus 10.4 days, p = 0.68. Thirty-day mortality was 2.4% (BITA) versus 3.0%, p = 0.09. Multivariate analysis identified prolonged duration of surgery, BMI > 30, emergent operations, advanced age, and BITA grafting as predictor for sternal instabilities. EF < 30%, advanced age plus emergency were associated with increased 30-day mortality.

CONCLUSION

 CABG using BITA can be performed routinely with good clinical results and low mortality. Compared with SITA grafting, bleeding complications were enhanced.

High-Risk Cardiac Surgery in Patients with Intravenous Drug Abuse and/or Active Hepatitis C or HIV Infection: An Ethical Discussion of Six Cases

OBJECTIVES

To discuss the dilemma of adequate decision making in patients with intravenous drug abuse and recurrent valve prosthesis infections or in patients with positive HIV or hepatitis C status. Ethical, social, and economic considerations, not only in terms of technical feasibility but also in terms of unpromising results and aspects of resources, are discussed. Thoughts are presented about the legitimation of cardiac surgery centers refusing to perform surgery in high-risk patients with HIV or hepatitis C infections.

METHODS

Presentation of six cases for discussion. Three patients were addicted to intravenous drugs and had recurrent prosthetic valve endocarditis, and the other three patients had either paravalvular leakage of a mitral valve prosthesis or acute aortic dissection or coronary artery disease. Five of these patients suffered from HIV/AIDS and infective hepatitis C. Four of these patients were refused by other centers due to high risk or a lack of capacity.

RESULTS

All six patients were operated during 2013. Mortality was 17%.

CONCLUSION

Decision making in noncompliant drug addicts with recurrent prosthesis infection and in HIV-positive patients leads beyond surgical challenges to ethical and economic considerations.

"Blame it on the Comorbidities": A 5-Year Follow-Up of 53 Chronic Dialysis-Dependent Patients Who Underwent Cardiac Surgery

Objectives This study evaluates midterm survival rates and risk factors for mortality of chronic dialysis-dependent patients undergoing cardiac surgery. Methods Fifty-three dialysis-dependent patients (34 males, aged 67 ± 12 years) with end-stage renal disease operated within March 2007 and May 2012 were analyzed retrospectively. Survival rates were calculated using Kaplan-Meier methods. Predictors of midterm survival were identified with multivariate Cox-regression analysis. Results Twenty-three patients received isolated coronary artery bypass graft surgery, 17 received isolated valve replacement, and 13 received combined procedures. Thirty-day mortality was 24.5% (n = 13). Follow-up was complete for 94.3% (n = 50). Survival rates at 1, 3, and 5 years were: 82, 50, and 17%, respectively. Neither age, gender, poor ejection fraction, emergency, ECC/X-clamp (cross-clamp) time, nor use of left internal thoracic artery or right internal thoracic artery had any influence on midterm survival. Causes of death within midterm follow-up period were related to cardiac events in 16% and neurological events in 16%. In the majority (47%), cause of death was associated with peripheral arterial disease (PAD).The only comorbidity, which could be identified as a significant risk factor, was PAD (p = 0.035). Five patients underwent successful renal transplantation within the follow-up period. Conclusion Although 30-day mortality in this high-risk patient population was increased, midterm survival rates were comparable to the results described in the literature. Cause of death within midterm follow-up period was mostly noncardiac related. Given the limited number of patients, predictors for enhanced 30-day mortality, such as preoperative myocardial infarction, prolonged extracorporeal circulation, operation time, and diabetes mellitus, did not have an influence on midterm survival.

Aortic Dissections Type A during Sexual Intercourse in Male Patients: Accident or Systematic Coincidence? Examination of 365 Patients with Acute Aortic Dissection within 20 Years

OBJECTIVES

Physical exercise accompanied by arterial hypertension is known to trigger acute aortic dissections. As a booster effect, mental stress leads to aggravation of hypertensive crisis. The aim of the study was to evaluate whether stress factors during sexual intercourse play any role as a catalyst in patients with acute type A aortic dissections. Concerning this subject, only two case reports have been published.

METHODS

A total of 365 patients with acute type A aortic dissections, operated between January 1993 and July 2014, were analyzed retrospectively. The main focus was to identify the provoking situation before onset of symptoms. A total of 247 patients were males and mean age was 60.2 years (range, 17.0-91.9 years). Of the total cohort, 86 patients (24%) were younger than 50 years (68 males) and 184 patients (50%) were younger than 60 years (149 males).

RESULTS

The explicit trigger could not be determined in 24% of the patients. In majority of the patients, onset of symptoms occurred during physical exercises, such as sports or lifting of heavy weights (68%), without a significant difference between males and females. In only 8% of the patients, symptoms occurred at rest. In 0.9%, Marfan syndrome was evident. Eleven of 68 males < 50 years (16%) and 17 of 149 males < 60 years (11%) but none among females (p = 0.03) experienced sudden onset of symptoms during sexual intercourse.

CONCLUSION

Combined physical and emotional stress during sexual intercourse seems to present a meaningful promoter effect for acute aortic dissections, especially in younger males, but not in females. Despite self-evidence of this phenomenon, frequency of this sensitive issue appears to be surprisingly high.

Chronic stress and coping among cardiac surgeons: a single center study

Introduction

Cardiac surgeons stress may impair their quality of life and professional practice.

Objective

To assess perceived chronic stress and coping strategies among cardiac surgeons.

Methods

Twenty-two cardiac surgeons answered two self-assessment questionnaires, the Trier Inventory for Chronic Stress and the German SGV for coping strategies.

Results

Participants mean age was 40±14.1 years and 13 were male; eight were senior physicians and 14 were residents. Mean values for the Trier Inventory for Chronic Stress were within the normal range. Unexperienced physicians had significantly higher levels of dissatisfaction at work, lack of social recognition, and isolation (P<0.05). Coping strategies such as play down, distraction from situation, and substitutional satisfaction were also significantly more frequent among unexperienced surgeons. "Negative" stress-coping strategies occur more often in experienced than in younger colleagues (P=0.029). Female surgeons felt more exposed to overwork (P=0.04) and social stress (P=0.03).

Conclusion

Cardiac surgeons show a tendency to high perception of chronic stress phenomena and vulnerability for negative coping strategies.

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.

ZURÜCKGEZOGEN: Dringliche oder notfallmäßige Koronarrevaskularisation unter Verwendung beider Arteria Thoracica interna nach vorheriger Thrombozytenaggregationshemmung mit Clopidogrel

BACKGROUND

Application of clopidogrel before diagnostic or therapeutical percutaneous coronary interventions has become standard for stent-thrombosis prevention. The irreversible platelet inhibition causes increasing bleeding complications if urgent coronary artery bypass grafting becomes necessary. This study evaluates the effect on bleeding complications of clopidogrel in urgent CABG using bilateral internal thoracic artery (ITA) and saphenous veins in all patients.

METHODS

We retrospectively analyzed 166 patients (operated between 1/00-12/02) with urgent or emergency CABG, using both ITAs and compared 83 patients with previous (within 5 days) clopidogrel and aspirin application to 83 patients without clopidogrel. We evaluated chest tube output, reexploration rate and necessity of blood products, ventilation time and ICU stay.

RESULTS

Both groups were comparable with age, gender, number of performed anastomoses (mean 4/ patient). Chest tube output (24 h) was higher in the clopidogrel group (935 +/- 599 ml vs 754 +/- 335 ml (p = 0.018)), as well as reexploration rate with 7.2% (6 of 83) vs 0% (0 of 83) (p < 0.001). Number of blood products in the clopidogrel group for red cells was 2.41 +/- 1.88 U vs 1.84 +/- 1.47 U p = 0.03, for plateletes 0.43 +/- 0.88 U vs 0.024 +/- 0.22 p = 0.0001, for fresh frozen plasma 0.41 +/- 1.14 U vs 0.096 +/- 0.59 U p = 0.029. Mechanical ventilation time was 11.35 +/- 8.77 h vs 10.57 +/- 9.12 h p = 0.51, ICU stay 32.1 +/- 21.8 h vs. 29.8 +/- 21.1 h (p = 0.48).

CONCLUSIONS

Previous application of clopidogrel in combination with aspirin before urgent CABG induces increased chest tube output, reexploration rate and necessity of blood products, especially of plateletes. Nevertheless, routine use of both ITAs in patients after clopidogrel exposure can be performed with acceptable bleeding complications.

Search for optimized conditions for sealing and storage of bypass vessels: influence of preservation solution and filling pressure on the degree of endothelialization

The aim of the present study was to develop methods for the rapid assessment of intimal quality of coronary bypass segments of venous origin, and to prevent endothelial damage by improved intraoperative handling of graft segments. Particular attention was paid to the influence of the composition of the preservation solution and the intravasal filling pressure on the degree of endothelialization. Intrava-sal exposure to Alcian blue at pH<3 resulted in highly specific staining of intimal regions with functionally or structurally damaged endothelium. Standardization of preparation, staining and image acquisition of the intimal surface of graft remnants and subsequent computer-aided planimetry of these images made it possible for the first time to perform rapid serial investigations for quality control of bypass grafts. Using saline as the rinsing and intraoperative storage medium resulted in the loss of more than 50% of the endothelium at intravasal pressures of 0-100 mmHg. Increasing the pressure resulted eventually in complete de-endothelialization. In contrast, grafts incubated in a customized plasma derivative tolerated pressures of up to 200 mmHg with no significant endothelial loss; and even after exposure to 1,000 mmHg (10 times the average mean arterial pressure!) more than 70% of the endothelium were intact and vital. These findings imply strongly that the quality of aortocoronary bypass grafts of venous origin can be improved substantially by the use of a plasma derivative solution for intraoperative preservation and by monitoring and controlling the intravasal pressures reached during sealing and storage.

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.

Prevention of sternal dehiscence and infection in high-risk patients: a prospective randomized multicenter trial

BACKGROUND

One factor for the development of sternal wound infection (SWI) is bony instability after sternotomy. This study compares two surgical techniques with respect to the occurrence of SWI in patients with an increased risk.

METHODS

In this multicenter study, 815 consecutive patients with an increased risk for SWI were prospectively randomly assigned to a conventional osteosynthesis (transsternal or peristernal wiring; n = 440) or to an osteosynthesis with additional lateral reinforcement (Robicsek; n = 375). Primary endpoints were the rate of sternal dehiscence as well as the occurrence of superficial sternal wound infections and deep sternal wound infections.

RESULTS

Both groups were comparable concerning preoperative and intraoperative variables. The rate of sternal dehiscence, superficial sternal wound infections, and deep sternal wound infections (conventional technique 2.5%, 3.4%, 2.5%; and Robicsek 3.7%, 5.6%, 3.7%) did not differ between the groups. Logistic regression analysis found independent risk factors for the development of sternal dehiscence: body mass indes greater than 30 kg/m(2) (odds ratio [OR]: 2.9; p = 0.05), New York Heart Association class more than III (OR: 2.4; p = 0.07), impaired renal function (OR: 3.9; p = 0.01), peripheral arterial disease (OR: 3.6; p = 0.001), immunosuppressant state (OR: 3.3; p = 0.001), sternal closure performed by an assistant doctor (OR: 2.5, p = 0.004), postoperative bleeding (OR: 4.2; p = 0.03), transfusion of more than 5 red blood units (OR: 3.7, p = 0.01), reexploration for bleeding (OR: 6.9, p = 0.001), and postoperative delirium (OR: 3.5, p = 0.01). There was an inverse relation between the numbers of wires and DSWI in patients with conventional sternal closure (p = 0.008).

CONCLUSIONS

In patients with an increased risk for sternal instability and wound infection after cardiac surgery, sternal reinforcement according to the technique described by Robicsek did not reduce this complication.