Coronary Artery Bypass Graft Surgery in Patients With Acute Coronary Syndromes After Primary Percutaneous Coronary Intervention: A Current Report From the North-Rhine Westphalia Surgical Myocardial Infarction Registry

Background Coronary artery bypass grafting has remained an important treatment option for acute coronary syndromes, particularly in patients (1) with ongoing ischemia and large areas of jeopardized myocardium, if percutaneous coronary intervention (PCI) cannot be performed; (2) following successful PCI of the culprit lesion with further indication for coronary artery bypass grafting; and (3) where PCI is incomplete, not sufficient, or failed. Methods and Results We aimed to analyze coronary artery bypass grafting outcome following prior PCI in acute coronary syndromes from the North-Rhine-Westphalia surgical myocardial infarction registry comprising 2616 patients. Primary end points were in-hospital all-cause mortality and major adverse cardio-cerebral event. Patients were 68±11 years of age, had 3-vessel and left main-stem disease in 80.4% and 45.3%, presenting a logistic EuroSCORE of 15.1% in unstable angina, 20.3% in non-ST-segment-elevation myocardial infarction, and 23.5% in ST-segment-elevation myocardial infarction. A history of PCI was present in 36.2% and PCI was performed within 24 hours before surgery in 5.2% in unstable angina, 5.9% in non-ST-segment-elevation myocardial infarction, and 16.1% in ST-segment-elevation myocardial infarction. PCI failed in 5.3% in unstable angina, 6.8% in non-ST-segment-elevation myocardial infarction and 17.2% in ST-segment-elevation myocardial infarction, and 28.8% of patients presented with cardiogenic shock. In-hospital mortality without PCI was 7.4%, but increased to 8.7% with prior PCI >24 hours, 14.5% with prior PCI <24 hours, and 14.1% with failed PCI (P<0.003). The in-hospital major adverse cardio-cerebral event rate was 16.4% without PCI, but 17.4% with prior PCI >24 hours, 25.6% with prior PCI <24 hours, and 41.3% with failed PCI (P=0.014). Multivariable logistic regression analysis showed prior PCI (P=0.039), as well as failed PCI (P=0.001) to be predictors for in-hospital all-cause mortality and major adverse cardio-cerebral event. Conclusions In the current PCI era, immediately prior or failed PCI before coronary artery bypass grafting in acute coronary syndromes is associated with high perioperative risk, cardiogenic shock, and increased morbidity and mortality.

[Surgical treatment of aortic valve stenosis]

Surgical aortic valve replacement still represents the gold standard in patients with severe symptomatic aortic valve stenosis. In addition to conventional aortic valve replacement by mechanical or biological prostheses via a median sternotomy, novel approaches including minimally invasive strategies and new devices, such as so-called rapid deployment prostheses, are becoming increasingly more established. Autologous replacement strategies including the Ross and the Ozaki procedures have evolved into reliable options at selected centers of excellence. These novel treatment approaches in aortic valve surgery result in excellent short and long-term outcomes with a reduction of procedure-related complications. Taken together, these modern surgical replacement strategies enable a personalized surgical treatment in patients with aortic valve stenosis, which are tailored to the individual patient.

Myocardial protection in cardiac surgery patients requiring prolonged aortic cross-clamp times: a single-center evaluation of clinical outcomes comparing two blood cardioplegic strategies

AIM

The aim of this study was to evaluate the impact of intermittent warm (IWC) versus intermittent cold blood cardioplegia (ICC) in high-risk patients that require prolonged periods of aortic cross-clamping during on-pump cardiac surgery.

METHODS

From 3527 consecutive patients undergoing on-pump cardiac surgery, 520 patients were retrospectively identified that required prolonged aortic cross-clamp ≥ 75 min. Myocardial protection was performed with ICC (N.=280) or IWC (N.=240). Groups were compared regarding clinical outcomes, myocardial injury (CK-MB, cTnT) and multivariate analysis was performed to assess the impact of applied cardioplegia on 30-day all-cause mortality, cardiac death, perioperative myocardial injury (PM) and major adverse cardiac events (MACE).

RESULTS

Demographic data, mean logistic Euroscore, aortic-cross-clamping and CPB time were comparable between groups. Patients with ICC needed more intraoperative defibrillations, had more postoperative blood transfusions and a prolonged hospital stay when compared to the IWC-group (P < 0.05). Thirty-day all-cause mortality tended to be higher in IWC (11% vs. 6%; P = 0.083) with significantly higher cardiac mortality (9% vs. 4%; P=0.015) compared to ICC. Myocardial injury was more pronounced in the IWC-group with a higher incidence of PMI (IWC: 17% vs. ICC:6%; P < 0.05) and MACE (IWC:37% vs. ICC:25%; P < 0.05). Groups did not differ regarding other postoperative clinical outcomes. Multivariate analysis revealed IWC to be independently predictive (P < 0.05) for 30-day all-cause mortality (OR:2.42; 95% CI:1.04-5.05), cardiac death (OR:3.57; 95% CI:1.49-8.85), MACE (OR:1.87; 95% CI:1.22-2.87) and PMI (OR:3.46; 95% CI:1.86-6.41).

CONCLUSION

ICC results in less myocardial damage and reduced postoperative cardiac mortality and morbidity in patients requiring extended periods of aortic-cross-clamping during on-pump cardiac surgery, suggesting superior cardioprotection when compared to IWC.

Chronic heart failure induced by multiple sequential coronary microembolization in sheep

OBJECTIVE

Although a large variety of animal models for acute ischemia and acute heart failure exist, valuable models for studies on the effect of ventricular assist devices in chronic heart failure are scarce. We aimed to establish a stable and reproducible animal model of chronic heart failure in sheep.

METHODS

Sheep (n=8, 77 +/- 4 kg) were anesthesized and a 5F sheath was implanted into the left carotid artery. The left main coronary artery was catheterized under flouroscopic guidance and bolus injection of polysterol microspheres (90 microm, n=25.000) was performed. Microembolization (ME) was repeated up to three times in two to three week intervals until animals started to develop stable clinical signs of heart failure. Clinical and echocardiographic data were analyzed at baseline (base) and at three months (3 mo) after first ME. All animals were followed for 3 months after first microembolization and then sacrificed for histological examination. Another four healthy sheep (79+/-6 kg) served as control animals.

RESULTS

All animals developed clinical signs of heart failure as indicated by increased heart rate at rest (68+/-4 bpm (base) to 93 +/- 5 bpm (3 mo) (p<0.05)), increased respiratory rate at rest (28+/-5 (base) to 38 +/- 7 (3 mo) (p<0.05)) and increased body weight 77 +/- 2 kg to 81 +/- 2 kg (p<0.05) due to pleural effusion, peripheral edema and ascites. Echocardiographic evaluation revealed significantly an increase of left ventricular enddiastolic diameter from 46 +/- 3 mm (base) to 61 +/- 4 mm (3 mo) (p<0.05). Clinically and echocardiographically no significant changes were revealed in healthy control animals.

CONCLUSIONS

We conclude that multiple sequential intracoronary microembolization can effectively induce myocardial dysfunction with clinical and echocardiographical signs of chronic ischemic cardiomyopathy. The present model may be suitable in experimental work on heart failure and left ventricular assist devices, e.g. for studying the impact of mechanical unloading, mechanisms of recovery and reverse remodeling.

Influence of angiotensin-I-converting-enzyme insertion/deletion gene polymorphism on perioperative hemodynamics after coronary bypass graft surgery

AIM

The angiotensin I-converting enzyme insertion/ deletion polymorphism (ACE-I/D), including three genotypes (II, ID, DD), with a known impact on midterm mortality and morbidity in patients after coronary artery bypass graft surgery (CABG), was studied. Since this polymorphism has been linked with increased vascular response to phenylephrine during cardiopulmonary bypass (CPB), we investigated its possible effect on perioperative hemodynamics in patients undergoing CABG.

METHODS

Genotyping for the ACE-I/D was performed by polymerase chain reaction (PRC) amplification in 110 patients who underwent elective CABG with CPB. Patients were assigned to two groups according to their genotype (group II [II genotype] and group ID/DD [ID and DD genotypes]). Systemic hemodynamics were measured directly before and at 4 h, 9 h, and 19 h after CPB.

RESULTS

Genotype distribution of ACE-I/D was 18%, 57%, and 25% in genotypes II, ID, and DD, respectively. The two groups were similar in age (group II: 66+/-6 years, group ID/DD: 66+/-8 years), body-mass-index (BMI) (group II: 28+/-2, group ID/DD: 29+/-5 kg/m2), male: female ratio (group II: 16: 4, group ID/DD: 63: 27) and Euroscore (group II: 3.1+/-1.9, group ID/DD: 3.5+/-2.1). There were no differences in mortality rate or perioperative systemic hemodynamics. The pulmonary vascular resistance before cardiopulmonary bypass was higher in the ID/DD genotypes than in the II genotypes (227+/-121 vs 297+/-169 dyn.s(-1).m2.cm(-5)). Four hours after CPB no difference remained; at 9 h after cardiopulmonary bypass there was a slight difference in pulmonary vascular resistance between the two groups (247+/-134 vs 290+/-117 dyn.s(-1).m2.cm(-5)) and a significant difference in pulmonary arterial pressure (19+/-6 vs 23+/-8); at 19 h after CPB the differences were no longer detectable.

CONCLUSION

ACE-I/D had no influence on perioperative systemic hemodynamics. However, transitory differences in pulmonary hemodynamic were observed after CPB. These differences may have been due to changes in serum ACE activity during CPB.

Surgical Management of Vascular Graft Infection in Severely Ill Patients by Partial Resection of the Infected Prosthesis

INTRODUCTION

In the presented retrospective study, we report on our results with partial resection of infected prosthetic grafts after aorto-bifemoral graft placement in eight male and three female patients.

METHODS

In all 11 patients clinical signs of infection were observed and bacteriological cultures were positive. Three patients underwent immediate surgery for perforation of an aneurysm at the distal anastomosis, eight patients underwent elective surgery. In all cases silver-coated Dacron prostheses were implanted. Assessment of outcome was based on survival, limb salvage, persistent or recurrent infection, and prosthetic graft patency.

RESULTS

In two cases, a partial wound dehiscence occurred which was treated with ambulant Vacuseal dressings for 16 and 21 days until secondary wound healing was achieved. In eight patients systemic markers of inflammation completed normalised within nine days. Follow-up CT-scans failed to demonstrate any signs of recurrent infection or peri-graft fluid collections. Patients were treated with specific antibiotic therapy for no more than three months. Post-operative bacteriological cultures were negative in all patients. The mean follow-up was 2.5+/-0.5 yrs. During follow-up, none of the patients died and there were no amputations.

CONCLUSION

Despite only partial resection of the infected prostheses, the reported surgical procedure offers good results. This approach maybe particularly suitable for the treatment of elderly patients with prosthesis infections.

Achsenanomalien der Vena cava inferior mit paracavalem venösen Aneurysma und renalem Kollateralkreislauf

Venöse Aneurysmata der großen Gefäße stellen anatomische Raritäten dar. Die meisten bisher publizierten Malformationen des venösen Systems betreffen hauptsächlich die Vena cava inferior und treten in unterschiedlichen Formen auf. Aussackungen der infradiaphragmalen Vena cava inferior werden bei routinemäßig durchgeführten abdominellen Sonographien nur selten beobachtet und stellen dann häufig Zufallsbefunde dar. Berichte hierüber beschränken sich auf einzelne Kasuistiken und bereiten den Klinikern nicht selten diagnostische und therapeutische Schwierigkeiten. In der vorliegenden Arbeit wird eine asymptomatische, ausgeprägte venöse trunkuläre Missbildung der Vena cava inferior mit suprarenaler Abflussstörung beschrieben. Der hier vorgestellte Fall stellt einen bislang nicht beschriebenen Befund dar. Unter Berücksichtigung der gesamten Befundkonstellation entschlossen wir uns zu einer konservativen Behandlung des Patienten.

[Josef Koncz (1916-1988)--pioneer of cardiac surgery]

Josef Koncz (1916-1988) was until given emeritus status in 1982 director of the Department of Cardiothoracic and Vascular Surgery, which was specifically founded for him in Goettingen, Germany. By the fusion of three different surgical branches the University hospital of Goettingen took over the role of a pacemaker and initiated a standard in the development of this new specialty in Germany. The scientific and clinical work done by the Department of Cardiothoracic and Vascular Surgery was shaped by the personality of the surgeon and scientist Josef Koncz. He was a successful surgeon and innovative pioneer in one person. Already in 1956, he started open-heart surgery and proceeded this technique in an impressing series. In 1965 he was the first in Germany who operated upon the transposition of the great vessels by Mustard's method and developed together with his long-standing assistant, Huschang Rastan, an operation technique to extend the left-ventricular outflow tract combined with tunnel-shaped subvalvular aortic valve stenosis. Another essential element of his work is related to the establishment of the Cardiothoracic and Vascular Surgery as an independent specialty, ending in the foundation of the German Society for Thoracic and Cardiovascular Surgery in 1971.

Effects of Preoperative Statin Therapy on Cytokines after Cardiac Surgery

INTRODUCTION

In addition to their lipid-lowering action, it has been demonstrated that statins can exert direct anti-inflammatory effects. We investigated the effect of preoperative statin therapy on systemic inflammatory markers and myocardial NF-kappaB inhibitor IkappaB-alpha after cardiac surgery.

METHODS

Thirty-six patients undergoing elective coronary artery bypass grafting with cardiopulmonary bypass (CPB) with cardioplegia were divided into two groups (statin group, n = 18; control group, n = 18). Plasma concentrations of pro-inflammatory cytokines (tumor necrosis factor alpha [TNFalpha], interleukin [IL]-6, IL-8) and anti-inflammatory IL-10 were measured before and 1, 4, 10, and 24 hours (h) after CPB. Phosphorylated IkappaB-alpha/total IkappaB-alpha ratio was assessed before and after CPB in right atrial biopsies.

RESULTS

Baseline and operative data did not differ between groups. Statin therapy was associated with lower preoperative low-density lipoprotein levels compared to control (73+/-6 vs. 92+/-6 mg/dL; P=0.03). Release of IL-6 was attenuated in the statin group at 4 h (2270+/-599 vs. 5120+/-656 pg/ml; P<0.01) and 10 h (1295+/-445 vs. 3116+/-487 pg/ml; P<0.05) compared to the control group. IL-10 increased after surgery in both groups (P<0.05), but was higher in the statin group at 1 h (66+/-15 vs. 26+/-16 pg/mL; P<0.01). Phosphorylated IkappaB-alpha/total IkappaB-alpha ratio before CPB did not differ between groups, but was elevated after CPB in both groups (P<0.05), indicating enhanced degradation of IkappaB-alpha. Statin therapy had no effect on TNFalpha and IL-8.

CONCLUSIONS

Preoperative statin therapy attenuates the release of pro-inflammatory IL-6 and up-regulates anti-inflammatory IL-10 after cardiac surgery with cardioplegia, but fails to inhibit phosphorylation of myocardial IkappaB-alpha.

Influence of eNOS Gene Polymorphisms (894G/T; - 786C/T) on Postoperative Hemodynamics After Cardiac Surgery

BACKGROUND

Differences in vascular reactivity have been associated with variable NO release due to 894G/T and -786C/T polymorphisms of the eNOS gene. Carriers of the 894T and -786C alleles are known to have enhanced vascular responsiveness to vasoconstrictor stimulation due to decreased NO generation. Thus, we hypothesized that eNOS gene polymorphism could influence perioperative hemodynamics and catecholamine support in patients undergoing cardiac surgery with CPB.

METHODS

In 105 patients undergoing elective CABG with CPB, systemic hemodynamics, cardiac index (CI), systemic and pulmonary vascular resistance indices (SVRI, PVRI) and catecholamine support were measured at baseline and 1 h, 4 h, 10 h and 24 h after CPB. Genotyping for the 894G/T and -786C/T eNOS gene polymorphisms was performed by polymerase chain reaction amplification. Patients were divided according to their genotype (894G/T: GG=group 1, GT and TT=group 2; -786C/T: TT=group 3, CT and CC=group 4).

RESULTS

Genotype distribution for 894G/T polymorphism was 41% (GG), 52.4% (GT), 6.6% (TT) and for -786C/T polymorphism 37.1% (TT), 41.9% (CT) and 21% (CC). Pre- and intraoperative characteristics and systemic hemodynamics did not differ between groups. CI, SVRI and PVRI remained unaffected by genotype distribution. Statistical analysis of postoperative data revealed no difference between groups, especially for pharmacologic inotropic or vasopressor support. Also, coexistence of the 894T and -786C alleles had no impact on perioperative variables compared to homozygous 894G and -786T allele carriers.

CONCLUSIONS

In contrast to current suggestions, the 894G/T and -786C/T genetic polymorphisms of the eNOS gene do not influence early perioperative hemodynamics after cardiac surgery with CPB.

Extended Myectomy for Hypertrophic Obstructive Cardiomyopathy after Failure or Contraindication of Septal Ablation or with Combined Surgical Procedures

BACKGROUND

Surgical correction of hypertrophic obstructive cardiomyopathy in severely symptomatic patients has been proven to be effective over the long term. The introduction of catheter-based procedures restricts surgical therapy to a subset of patients not suitable for septal ablation or requiring concomitant cardiac surgery.

METHODS

Between 8/2001 and 8/2003, 25 patients (58 +/- 15 years) underwent extended transaortic septal myectomy with partial excision and mobilization of the papillary muscles. Concomitant surgical procedures were performed in 40 % (CABG n = 9, aortic valve replacement n = 2). In 24 %, prior septal ablation was ineffective. Intraventricular gradient was 80 +/- 29 mm Hg at rest and 143 +/- 35 mm Hg during exercise. Mitral regurgitation affected 72 % of patients, and 88 % were NYHA functional class III or IV.

RESULTS

No hospital death, no postsurgical ventricular septal defect, and no complete atrioventricular block occurred. Severe nonfatal complications occurred in 24 % of patients. Intensive care was necessary for 1.8 +/- 1.7 days; total hospital stay was 11.8 +/- 3.8 days. Early follow-up was complete in 100 % (15 +/- 6 months, total of 376 months) with no late deaths, no relevant mitral regurgitation, or intraventricular gradients. Functional status was markedly improved (NYHA class I 40 %, class II 56 %, class III 4 %).

CONCLUSIONS

Early results of extended surgical myectomy and reconstruction of the subvalvular mitral apparatus in hypertrophic obstructive cardiomyopathy remain excellent with respect to mortality, morbidity, and functional capacity even when restricting surgery to patients earlier supposed to be at high risk.

[Interstitial T1-weighted MR lymph fistulography with Gadomer-17 in an experimental animal model]

PURPOSE

To visualize and localize fistulas of the thoracic duct with interstitial T 1 -weighted MR lymphography using Gadomer-17.

MATERIALS AND METHODS

In 10 domestic pigs, leaks of the thoracic duct were created surgically or interventional-radiologically. The lymphatic leakage was located within the abdominal portion of the thoracic duct in 5 pigs, within the thoracic portion of the thoracic duct in 3 pigs, and in both, abdominal and thoracic portions of the thoracic duct, in 2 pigs. Subsequently, 10 micro mol/kg KG Gadomer-17 (1.5-1.8 ml) was administered interstitially in both hind legs of the animals. MR lymphography was performed with a 1.5 T MR unit using two different 3D gradient echo sequences before and 10 - 90 minutes after administration of contrast material.

RESULTS

Leaks within the abdominal portion of the thoracic duct were directly visible as opacified fistulas. Indirect signs of active lymphatic fistulas were increasing extravasations of contrast material and free abdominal fluid. The 3D gradient echo sequence with the highest planar resolution (TR = 8,7 - 8,8 ms, TE = 4,2 - 4,3 ms, FA = 40 degrees, matrix size = 327 x 512) was best suited for distinct delineation of the lymphatic system and detailed demonstration of the thoracic duct fistulas. Intrathoracic leaks could not be demonstrated by MR lymphography due to reduced lymphatic flow or extravasated contrast medium at the abdominal puncture site.

CONCLUSION

Interstitial MR lymphography with Gadomer-17 allows sensitive detection and localization of abdominally located leaks of the thoracic duct.

Tumor necrosis factor-alpha and troponin I release in porcine cardiac lymph and coronary sinus blood before and after cardiopulmonary bypass

To assess the concentrations of cardiac troponin I (cTnI) and tumor necrosis factor-alpha (TNFalpha) in cardiac lymph compared with coronary sinus (CS) blood and to measure cardiac lymph flow before and after cardiopulmonary bypass (CPB). In 21 pigs, the main cardiac lymph trunk was cannulated before institution of standardized CPB. Lymph flow, cTnI and TNFa in cardiac lymph and CS blood were measured before and after CPB for 6 hours. Before CPB, cTnI concentration was 215 +/- 36 nglml in cardiac lymph and 0.5 +/- 0.1 nglml in CS blood, respectively. After aortic declamping a significant elevation of cTnI values was measured in cardiac lymph and CS blood. cTnl concentration in cardiac lymph and CS blood peaked 6 hrs after CPB (10,556 +/- 4,735 vs. 22.2 +/- 3.7 nglml, p < 0.01). TNFalpha concentration at baseline was 23.2 +/- 5.6 pg/ml in lymph and 18.7 +/- 9.5 pg/ml in CS blood, and there was no significant release of TNFalpha up to the end of the experiment. Baseline cardiac lymph flow was 3.07 +/- 0.35 ml/h and declined after aortic clamping (0.72 +/- 0.16 ml/h; p < 0.01) and peaked one hour after CPB (5.66 +/- 0.97 ml/h; p < 0.01). In conclusion, very high cTnI concentrations in cardiac lymph suggest serious perioperative myocardial damage after CPB with cardioplegia, which is underestimated by cTnI release into the bloodstream. In our study, the myocardium was not a major source of TNFalpha release.

Aortopexy in severe tracheal instability: short-term and long-term outcome in 29 infants and children

BACKGROUND

Tracheal instability is a hazardous situation after operation for esophageal atresia. In cases with life-threatening apneas, aortopexy is a therapeutic option. To assess efficacy, short-term and long-term outcome was analyzed retrospectively.

METHODS

Between 1985 and 2000, 29 patients (age, 1.5 months to 5.2 years) were operated on. A flaccid trachea after operation for esophageal atresia was the cause for life-threatening apneas in 27, and there was external vascular compression in 2 patients. The operative procedure consisted of ventropexy of the aortic arch to the sternum and ventral thoracic wall.

RESULTS

There was neither early nor late mortality. A reversible lesion of the phrenic nerve was observed in 2 patients, a pneumothorax in 3, and secondary wound healing in 1. In all but 1 patient symptoms improved markedly or disappeared within days or within the first 3 months postoperatively. An increased susceptibility to respiratory infections was observed in long-term follow-up.

CONCLUSIONS

Aortopexy can be performed with no mortality and low morbidity. Aortopexy is effective to prevent further life-threatening apneas, but does not prevent an increased susceptibility to respiratory infections.

Cholesterol crystal embolization after cardiac operations. Report of two cases

We report two cases of systemic cholesterol embolization after coronary bypass surgery under extracorporeal circulation. First clinical symptoms starting at 48-72 h after cardiac operation were severe abdominal pain and elevated ischemia associated blood parameters. In both patients a laparotomy was performed but fatal outcome due to multi-organ failure could not be avoided. The awareness of this often fatal complication is of great importance for the surgeon since prevention is the only effective treatment.

Cannulation of the cardiac lymphatic system in swine

OBJECTIVE

Cardiac lymph is the most direct medium for analyzing metabological changes in the myocardial cell. Currently, dogs are the animals used for investigation of myocardial lymphatic function. However, questions arise when comparing and interpreting the human system to the experimental model, since the dog coronary anatomy is different from human anatomy and pulmonary lymph contamination is found in up to 81% of the cases. Swine, having similar coronary anatomy to humans, are a proven model for cardiovascular research. The purpose of this study was to investigate the cardiac lymphatic anatomy of the swine and to develop a reliable cannulation technique to collect the lymph.

METHODS AND RESULTS

The lymphatic anatomy of 60 pigs was studied and classified and a new technique for lymphatic cannulation was developed. The cannulation success rate was 55%. In addition, no pulmonary lymph contamination was found at the cannulation site.

CONCLUSION

We conclude that porcine myocardial lymphatics can be successfully cannulated for the investigation of myocardial lymphatic function.