Jens Litmathe

Impact of prior percutaneous coronary intervention on the outcome of coronary artery bypass surgery: A multicenter analysis

OBJECTIVES Do prior percutaneous coronary interventions adversely affect the outcome of subsequent coronary artery bypass grafting? We investigated this effect on a multicenter basis. METHODS Eight cardiac surgical centers provided outcome data of 37,140 consecutive patients who underwent isolated first-time coronary bypass grafting between January 2000 and December 2005. Twenty-two patient characteristics and outcome variables were retrieved. Three groups of patients were analysed for in-hospital mortality and in-hospital major adverse cardiac events: patients without a previous percutaneous coronary intervention, with 1 previous intervention, and with 2 or more previous percutaneous coronary interventions before bypass grafting. A total of 29,928 patients with complete information for prior percutaneous coronary intervention underwent final analysis. Unadjusted univariate and risk-adjusted multivariate logistic regression analysis as well as computed propensity score matching were performed, based on 14 major risk factors to correct for and minimize selection bias. RESULTS A total of 10.3% of patients had 1 previous percutaneous coronary intervention, and 3.7% of patients had 2 or more previous interventions. Risk-adjusted multivariate logistic regression analysis revealed a significant association of 2 or more previous percutaneous coronary interventions with in-hospital mortality (odds ratio [OR], 2.0; confidence interval [CI], 1.4-3.0; P = .0005) and major adverse cardiac events (OR, 1.5; CI, 1.2-1.9; P = .0013). After propensity score matching, conditional logistic regression analysis confirmed the results of adjusted analysis. A history of 2 or more previous percutaneous coronary interventions was significantly associated with in-hospital mortality (OR, 1.9; CI, 1.3-2.7; P = .0016) and major adverse cardiac events (OR, 1.5; CI, 1.2-1.9; P = .0019). CONCLUSIONS Multicenter analysis confirms that a history of multiple previous percutaneous coronary interventions increases in-hospital mortality and the incidence of major adverse cardiac events after subsequent coronary artery bypass grafting. Critical discussion of the treatment strategy in these patients is warranted.

Prone and ECMO - a contradiction per se?

Acute respiratory distress syndrome (ARDS) still represents a serious problem in clinical routine and is associated with a high mortality. Several concepts are known for special treatment, but, in some instances, the application of an extracorporeal membrane oxygenation (ECMO) is necessary for both the improvement of oxygenation and the elimination of carbon dioxide (CO2). One basic aspect in lung protective ventilation in this context is alveolar recruitment, which can be achieved by different approaches, such as “the open lung concept”, according to Lachmann, or by additional kinetic therapy. The most exposed feature of this entity is ‘prone’, which may be quite challenging in patients requiring extracorporeal support or organ replacement therapy under ongoing critical illness. We report two outstanding cases of prone under conditions of a veno-venous ECMO therapy which improved significantly under this position. Furthermore, we reflect critically possible risk factors and adverse events of such procedures and afford a current view from the literature.

Rotation thromboelastography (ROTEM) parameters are influenced by age, gender, and oral contraception

Rotation thromboelastography (ROTEM) is a screening method that allows the rapid detection of plasma- and platelet-related haemostatic abnormalities. To use this procedure more efficiently, reference values depending on gender, age, and oral contraception are required. In this study, five cohorts of healthy subjects were examined by ROTEM upon activation of the extrinsic or intrinsic pathway of coagulation, or recalcification alone. The cohorts comprised male subjects below (1) and above (2) 45 years of age, female subjects below 45 years of age with (3) or without (4) oral contraception, and female subjects above 45 years (5) without hormone replacement therapy. A significant influence of gender, age, and oral contraception on parameters determined by ROTEM was observed. Thus, adjustment for age, gender, and oral contraception is required when ROTEM is used to screen for distinct abnormalities of haemostasis.

The Bad Oeynhausen concept of INR self-management.

Background: A significant number of patients depend on the intake of vitamin K antagonists for prevention and treatment of thromboembolic events. The development of portable anticoagulation monitors has enabled self-testing and self-adjustment of anticoagulation therapy.Objective: To describe the principles of a training course to learn INR self-management and to illustrate reliability of our concept.Description: The training is divided into an early postoperative training, an ambulatory training six months later, and a 24 hours care and consultation. According to our concept, each patient who depends on long-term anticoagulation therapy is able to learn INR self-management. Reliability of our concept has been proved in two prospective, randomized clinical trials.Study results: A study with 1,155 patients has demonstrated that INR values lie more often in the predetermined target range in the INR self-management group if compared to the conventional group (79.2% vs. 64.9%; P < 0.001). Moreover, this study has demonstrated that self-management can lead to a reduction of thromboembolism (1.5% vs. 2.8%; P < 0.05), and to a lower lethality if compared to conventional INR management (3.5% vs 6.0%; P < 0.025). A second study with 1,816 patients has confirmed that INR self-management results in a high percentage of INR values in the target range (76%), even though target INR-range is reduced and narrowed. Thus, low dose INR self-management did not increase the risk of thromboembolism while avoiding the zone of higher risk for bleeding, beginning from INR > 3.5.Conclusions: The Bad Oeynhausen concept of INR self-management is a promising tool to achieve low hemorrhagic complications without increasing the risk of thromboembolic complications. It can thus be successfully applied to patients with an indication for permanent anticoagulation therapy.

Cardiac surgery in nonagenarians: Pushing the boundary one further decade

With increasing age of the general population, the necessity for cardiac surgery in the collective of patients aged 90 and older has been increasing. To aid in the choice of adequate therapy we investigated our experience for the group of nonagenarians undergoing surgical interventions. From 6/2000 to 9/2007, 17 patients aged 90 and older underwent open-heart surgery at our institution. We performed a retrospective data analysis including baseline preoperative clinical status, intra- and postoperative results and the long-term survival in the further postoperative course. We performed cardiac surgical procedures in 17 patients (male/female ratio 6/11), including isolated aortic valve replacement (n = 7), aortic root replacement (n = 2), isolated coronary bypass surgery (n = 4), combined coronary and valve surgery (n = 5), re-operative valve replacement (n = 1) and root replacement with arch repair (n = 1). Emergency procedures were performed in 11.8% (2/17). Mean age was 91.9 ± 1.2 years, ranging 90.1-94.2. Mean follow-up was 3.2 ± 2.2 years. The 30-day mortality was 17.6% (3/17), overall mortality at 42.9 follow-up patient years was 58.8% (10/17). We conclude that cardiac surgery procedures can be performed with therapeutic benefit for selected nonagenarians safely and with acceptable operative risk. After analysis our clinical experience we believe age alone not to be a contraindication for surgical intervention, consideration of the physiologic status of the patient reflects on the postoperative outcome. Survival of the patients investigated that survived the initial 30-day postoperative period was similar to the estimated survival of the equally aged general population in Germany.

Concomitant CABG-procedures in elderly patients undergoing aortic valve replacement. An additional risk factor?

In einer Vielzahl von Fällen zeigt die präoperative Koronarangiographie bei älteren Menschen, die zum Aortenklappenersatz anstehen, begleitende Stenosen der Koronargefäße. Der Nutzen einer operativen simultanen Versorgung im Sinne einer zusätzlichen Koronarbypassoperation wird auch heute noch kontrovers diskutiert. Einige Autoren vertreten sogar die Auffassung, dass in derart gelagerten Fällen eine isolierte Herzklappenoperation vorzuziehen sei. Wir untersuchten 283 Patienten (Alter≥75 Jahre), die sich einem Aortenklappenersatz unterziehen mussten, entweder mit oder ohne simultaner Koronarbypassoperation. Das besondere Augenmerk galt solchen Patienten, die einen isolierten Aortenklappenersatz erhielten trotz präoperativ bekannter koronarer Herzkrankheit. 166 Patienten zählten zur Aortenklappenersatz- Gruppe (Gr. A) und 117 Patienten zählten zur Aortenklappenersatz+ Koronarbypass-Gruppe (Gr. AC). 51 der Patienten mit isoliertem Aortenklappenersatz litten an einer begleitenden KHK (Stenosen <60%; Gr. A2), wogegen 115 Patienten der Gruppe A auschließlich eine Aortenklappenerkrankung aufwiesen (Gr. A1). Vergleicht man Gr. A mit Gr. AC, so zeigt sich eine signifikant verlängerte maschinelle Beatmung in Gr. AC (22,3±5,3 vs. 10,1±1,9 h in Gr. A, p<0,05), sowie auch ein längerer Verbleib auf der Intensivstation. Die Inzidenz schwerer postoperativer Komplikationen und die unmittelbare postoperative Mortalität waren vergleichbar. In Gr. A2 unterschieden wir zwischen Stenosen des RIVA (n=19) und der RCA bzw. des RCx (n=32). Die Entscheidung, eine Stenose des LAD nicht mit einem Bypass zu versorgen, verschlechterte den postoperativen Verlauf deutlich, wie ein Vergleich mit Gr. AC zeigt. Der Verzicht auf eine Bypassversorgung von RCA oder RCx hatte offensichtlich keinen Einfluss auf eine Verschlechterung des postoperativen Verlaufs. Unsere Ergebnisse evaluieren eine begleitende Koronarbypassoperation bei älteren Patienten, die sich einem Aortenklappenersatz unterziehen nicht als negativen Predictor. Im Gegensatz dazu konnten wir zeigen, dass eine zusätzliche Bypassversorgung moderater RIVA-Stenosen den klinischen Verlauf dieser Patienten günstig beeinflusst. Hingegen können Stenosen von RCA und RCx durchaus vernachlässigt werden vor dem Hintergrund eines verbesserten klinischen postoperativen Verlaufs und der Möglichkeit einer sekundären Katheterintervention. Preoperative coronary angiography in elderly people referred to the hospital for aortic valve replacement (AVR) often shows additional significant stenoses of the coronary arteries (CAD). The benefit of concomitant coronary artery bypass grafting (CABG) in these patients is still discussed controversially. By some authors, an isolated AVR in elderly patients with additional CAD is even described to have a better outcome. We analyzed 283 patients (≥75 years), undergoing AVR with or without concomitant CABG-procedures. We particularly analyzed those patients who were operated with an isolated AVR in spite of preoperatively known CAD. There were 166 patients in the AVR group (gr. A) and 117 patients in the AVR+CABG group (gr. AC). 51 of these patients with isolated AVR were preoperatively known to have an additional CAD (stenoses <60%) (gr. A2), whereas 115 patients of group A only suffered from an isolated aortic valve disease (gr. A1). Comparing group A and AC, we found a significantly prolonged mechanical ventilation in group AC (22.3±5.3 hours vs 10.1±1.9 h in gr. A, p<0.05) and a longer stay on the ICU. The incidence of severe postoperative complications and the in-hospital mortality were comparable. In group A2 we could differ between stenoses of the LAD (n=19) and of the right coronary or circumflex artery (n=32). The decision not to bypass a stenosis of the LAD caused a significantly worse outcome of these patients compared to group AC. Ignoring stenoses of the RCA or RCx was not correlated with an impaired postoperative result. With our results we could not identify concomitant CABG as a predictor of poor surgical outcome in elderly patients with AVR. We could even show that an additional bypass grafting of moderate stenoses of the LAD is important for a good outcome of these patients. Comparable stenoses in the right coronary or circumflex artery may be ignored with the advantage of a shorter period of intraoperative ischemia and the possibility of a secondary catheter intervention.

Abdominal complications following open-heart surgery : a report of 12 cases and review of the literature

Introduction — Abdominal complications following open-heart surgery remain serious events as the mortality is reported to be tremendously high.The clinical presentation, the diagnostic strategy and the therapeutic management varies.We reviewed all records of those patients who developed abdominal complications with surgical consequences during the last five years, recorded a complete follow-up and compared the findings to a current view of the literature. Patients and methods — Altogether 5720 patients underwent open-heart surgery at our institution between 1/98 and 12/02. Out of these 12 (10 men, 2 women) developed severe gastrointestinal complications with surgical consequences.The mean age was 73.17 ± 8.11 years. Seven patients underwent isolated coronary artery bypass grafting (CABG), two patients combined aortic valve replacement (AVR) and CABG, one isolated AVR, one mitral valve replacement (MVR) and yet another one combined MVR and CABG.The clinical records of all these patients were examined and a complete follow-up was recorded. Results — The duration of the entire cardiac operation was a mean of 212.67 ± 36.97 min, perfusion time 103 ± 29.32 min and myocardial ischaemic time 52.25 ± 24.56 min. Length of ICU-stay was between 1 and 5 days after cardiac surgery. Concerning gastrointestinal complications nine patients suffered from ischaemic intestinal disease, two from gastrointestinal ulcer bleeding and one from a preoperatively unknown bowel tumour with subsequent ileus. Four patients died in the immediate postoperative course, one patient within two years and seven patients show a satisfactory status at follow-up. Conclusions — A review from the literature shows an enormous mortality from abdominal complications following open-heart surgery.This was also found in our series.As many of these patients have a history of abdominal disease more attention should be paid to such anamnestic hints in the preparation before cardiac surgery. Hence we recommend early diagnostic measures and explorative laparotomy in doubtful situations in patients with positive anamnesis.

Comparison of complete and incomplete revascularization in CABG patients with severely impaired left ventricular function (LVF)

ACB-Operationen bei Patienten mit deutlich reduzierter LV-Ejektionsfraktion sind bis heute Ursache einer Vielzahl perioperativer Komplikationen. Es ist jedoch unklar, ob Patienten mit deutlich reduzierter LV-EF eher von einer kompletten Revaskularisation oder von einer kurzen intraoperativen Ischämiedauer, die eine inkomplette Revaskularisation möglicherweise beinhaltet, profitieren. Zwischen 1996 und 2000 wurden 263 Patienten mit einer LV-EF von unter 30% in unserer Klinik einer Myokardrevaskularisation unterzogen. Unter Bezugnahme auf die durchgeführte Operation wurden die Patienten in 2 Gruppen unterteilt: In Gruppe A (n = 158) erhielten die Patienten alle notwendigen Bypässe, die aus der präoperativen Angiografie evaluiert worden waren, wogegen in Gruppe B (n = 105) mindestens ein vorgesehener Bypass nicht in praxi umgesetzt werden konnte. Die mittlere Anzahl an Bypässe betrug in Gruppe A 3,59 ± 0,58 und in Gruppe B 2,92 ± 0,47 (p < 0,05). In Gruppe A benötigten 33% der Patienten intraoperativ Katecholamine, in Gruppe B 48% (p < 0,05). Die Insertion einer IABP wurde häufiger in Gruppe B notwendig: n = 7, in Gruppe A n = 3 (p < 0,05). Auch postoperativ zeigten sich signifikante Unterschiede: Dauer der maschinellen Beatmung (A: 12,1 ± 3,4 Stunden; B: 20 ± 5,2 Stunden) (p < 0,05) und Aufenthalt auf der Intensivstation (A: 3,0 ± 0,6 Tage; B: 4,2 ± 0,6 Tage) (p < 0,05) waren signifikant in Gruppe B prolongiert. 6 Patienten aus Gruppe B verstarben während des Krankenhausaufenthaltes (6%). In Gruppe A waren dies 5 Patienten (3,2%) (p < 0,05). Eine komplette Revaskularisation verbessert das Outcome von Patienten mit deutlich eingeschränkter LV-EF. Eine verlängerte intraoperative Ischämiezeit und EKZ-Dauer können vor dem Hintergrund einer effektiven Revaskularisation in Kauf genommen werden. CABG-procedures in patients with depressed LV-ejection fraction (LVEF) may still cause complications. In patients with severely impaired LVEF, it is particularly unclear whether a complete revascularization (CR) leads to a better outcome than the possible advantage of a short period of ischemia. This may be reached by a possibly incomplete revascularization (ICR). In our department, 263 patients with LVEF < 30% underwent a CABG-procedure between 1996 and 2000. Patients were divided into two groups with regard to their revascularization: group A patients (n = 158) received all grafts that were thought to be necessary according to preoperative angiography, whereas in group B (n = 105) at least one graft could not be realized. Mean number of grafts per patient was 3.59 ± 0.58 in group A and 2.92 ± 0.47 in group B (p < 0.05). Intraoperatively, 33% of group A patients needed catecholamines, compared to 48% in group B (p < 0.05). IABP was used more often in group B (n = 7 compared to n = 3 in group A) (p < 0.05). Postoperatively, there were also significant differences: duration of mechanical ventilation (A: 12.1 ± 3.4 h; B: 20 ± 5.2 h) (p < 0.05) and stay on ICU (A: 3.0 ± 0.6 days; B: 4.2 ± 0.6 days) (p < 0.05) were significantly prolonged in group B patients. Six patients from group B died during hospitalization (6%), compared to five from group A (3.2%) (p < 0.05). In patients with a severely depressed LVEF, complete revascularization improves the outcome after CABG-procedures. A prolonged time of intraoperative ischemia and CPB can be accepted to realize an effective revascularization.

The use of autologous platelet gel (APG) for high-risk patients in cardiac surgery -- is it beneficial?

Background: Wound healing in cardiac surgery has become a major problem due to the impaired risk profile of many patients. The aim of this study was to prove the influence of autologous platelet gel (APG) on wound healing in a special group of high-risk patients undergoing coronary surgery. Patients and Methods: We performed a prospective, double-blind study in 44 patients with a special risk constellation relating to wound complications (obesity, diabetes, smoker, New York Heart Association (NYHA) III-IV and peripheral vascular disease). The study group was treated with APG, prepared using the Magellan© platelet separator, the control group underwent conventional wound treatment. Results: The incidence of major and minor wound complications at the thoracotomy, as well as in the area of saphenous vein harvesting, was not pronounced in either of the groups. Blood loss and pain sensations did not differ significantly either. Stay in the intensive care unit (ICU) and the in-hospital mortality were also comparable. The duration of the entire operation and the time until removing the chest-tubes were prolonged in the study group. Conclusion: Despite promising results in other fields of surgery, APG shows no beneficial effect in high-risk patients undergoing cardiac surgery. Probably, it depends on different types of microcirculation in atherosclerotic patients, which are quite different from those of other surgical areas. This factor may offset the existing beneficial platelet effects which could be observed, for example, in maxillo-facial surgery.

Anticoagulation during extracorporeal circulation under conditions of an ongoing systemic inflammatory response syndrome: effects of heparin

Objective: Open-heart surgery with cardiopulmonary bypass (CPB) causes changes in haemostasis. Artificial surfaces are bioincompatible and, thus, may initiate a reaction similar to an acute inflammation. In some patients, this ‘postperfusion syndrome’ (PPS), which includes changes in haemostasis, is the beginning of a systemic inflammatory response syndrome (SIRS). However, it is not clear whether the changes in coagulation represent a consequence or a main cause of the inflammatory reaction. Thus, the aim of our study was to investigate the cascade of coagulation and the effects of heparin under special circumstances of an ongoing SIRS. Methods: In a prospective evaluation using standardized operative procedures with CPB, we compared Group A (control group with normal postoperative course, n=20) with Group B (patients with postoperative SIRS, n=12). At six time points beginning before and ending two days after surgery, we measured platelet counts, leucocyte counts and plasma levels of fibrinogen, factor XII and antithrombin III (ATIII), in addition to standard coagulation tests (PTT, TT and ACT). Furthermore, we determined parameters of inflammation, such as C-reactive protein, PCT, IL-6, IL-8, IL-10 and TNF-alpha. Results: In Group B (SIRS), we found a reduced anticoagulation during CPB with significantly lower values for PTT (60±versus 160±11 s), ACT (270±33 versus 532±44 s) TT (40±3 versus 150±15 s) compared to the control Group A. Simultaneously, we found a significant increase of factor XII in the SIRS group (191±16 versus 10±2%). There were no significant differences concerning the preoperative ATIII levels and the intraoperative dosage of heparin; the intraoperative decrease of fibrinogen, ATIII and platelets was comparable in both groups. Furthermore, we could see that significant changes of inflammatory parameters in the SIRS group (increasing levels of TNF-α, Il-6, IL-8 and IL-10) occurred at least 30 min after the observed reduction of anticoagulatory effect. Conclusions: With our results, it could be demonstrated that the development of inflammatory complications after CPB is correlated to a significantly reduced intraoperative effect of heparin. As this reduction of anticoagulation significantly preceded the changes of inflammatory parameters in SIRS patients, we think that a hypercoagulatory state, especially in cases of ongoing inflammation, is an additional trigger of SIRS.