Christian Binner

Secundum ASD closure using a right lateral minithoracotomy: Five-Year experience in 122 patients

BACKGROUND Surgical closure of secundum atrial septal defect (ASD) is a standard procedure associated with very low mortality and morbidity. We evaluated outcomes in the era of catheter-based interventional closure and minimally invasive techniques. METHODS From May 1996, February 2002, 177 patients with a body weight of more than 30 kg underwent surgical ASD closure. A right lateral minithoracotomy (LMT) was used in 122 patients and a conventional approach, in 55. Diagnoses included secundum ASD in 106 patients in the LMT group and 40 in the conventional group, sinus venosus ASD in 13 patients in each group, and status post interventional closure in 3 and 2 patients, respectively. Mean age was 37 +/- 17 years in the LMT group and 43 +/- 20 years, in the conventional group and mean body weight was 66 +/- 17 kg and 70 +/- 16 kg, respectively. In the LMT group, femoral cannulation was performed for cardiopulmonary bypass. RESULTS Direct ASD closure was carried out in 67.2% of patients in the LMT group and 58.2% of those in the conventional group. The remaining patients had pericardial patch closure. There was one death: A patient in the conventional group who required explantation of an Amplatzer device because of infection died postoperatively. Average stay in the intensive care unit was 1.2 +/- 0.5 days. Two patients required reoperation for residual ASD after direct closure; 1 sustained a temporary neurological deficit that resolved completely. On postoperative echocardiography, a minimal residual shunt was seen in only 3 patients. All patients were in good clinical condition with improved functional status at discharge from the hospital. CONCLUSIONS Secundum ASD closure by LMT has become as standard and safe an operation as the conventional technique and achieves good perioperative results and satisfactory long-term outcomes. Thus LMT is an attractive option for patients who are not suitable for closure using catheter-based devices.

Outcome of Extracorporeal Membrane Oxygenation as a Bridge to Lung Transplantation and Graft Recovery

BACKGROUND Indications for extracorporeal membrane oxygenation (ECMO) use in lung transplantation are (1) temporary assistance as a bridge to transplantation, (2) stabilization of hemodynamics during transplantation in place of cardiopulmonary bypass, and (3) treatment of severe lung dysfunction and primary graft failure after transplantation. This study compares the survival of lung transplant recipients requiring ECMO support with survival of patients without ECMO. METHODS A retrospective database review was performed for 108 consecutive patients who underwent single-lung or bilateral-lung transplantation at our center between 2002 and 2009. RESULTS Of 108 transplant recipients, 27 (25%) required venoarterial ECMO compared with 81 patients who did not. Nine patients required ECMO preoperatively (87±102 hours), and ECMO was continued for 5 patients during the lung transplant operation. Seven additional patients received ECMO during transplantation. Six patients required early (<7 days) and 5 patients delayed (≥7 days) postoperative ECMO for treatment of allograft dysfunction. The subgroup with support showed the most favorable patient discharge rate (66.7%). ECMO support was a significant risk factor for death (p<0.001). Survival was significantly reduced with the use of ECMO: 30-day, 90-day, 1-year, and 5-year survival was 97%, 91%, 83%, and 58% in the patients without ECMO compared with 63%, 44%, 33%, and 21% in those with ECMO, respectively. CONCLUSIONS Survival after lung transplantation was significantly reduced with ECMO. However, patients who survived the first year showed similar long-term survival as those patients who did not need perioperative ECMO support.

Surgery for infective endocarditis complicated by cerebral embolism: a consecutive series of 375 patients.

OBJECTIVE To determine the influence of silent and symptomatic cerebral embolism on outcome of urgent/emergent surgery after acute infective endocarditis (AIE). METHODS From a total of 1571 patients with AIE admitted to our institution between May 1995 and March 2012 about one-quarter (375 patients; mean age, 61.8 ± 13.6 years) presented with cerebral embolism confirmed by cranial computed tomography. Isolated aortic valve endocarditis was present in 165 patients (44%), 132 patients (36%) had isolated AIE of the mitral valve, and 64 (17%) patients had left-sided double valve endocarditis. RESULTS Although the majority of patients presented with neurologic symptoms, 1 out of 3 patients experienced a so-called silent asymptomatic cerebral embolism or transient ischemic attack (n = 135). The rate of silent embolism was equivalent in patients with isolated aortic valve versus isolated mitral valve endocarditis (37% vs 34%; P = .54). Comparing patients with silent embolism versus symptomatic embolism, 18 patients with silent embolism versus 12 patients with symptomatic embolism developed postoperative hemiparesis (P = .69). Three versus 4 had severe postoperative intracerebral bleeding (P = .71). Median follow-up of survivors with cerebral embolism was 4.1 years (935 cumulative patient-years). Hospital mortality was 21.4% versus 19.6% (P = .68), with a long-term survival of 45% ± 5% versus 47% ± 4% at 5 years (P = .83) and 40% ± 6% versus 32% ± 5% at 10 years (P = .86). Independent risk factors of mortality were age at surgery (P < .01), chronic obstructive pulmonary disease (P = .01), preoperative requirement of catecholamines (P = .02), dialysis (P < .01), and duration of cardiopulmonary bypass (P < .01). CONCLUSIONS Survival after surgery for AIE is significantly impaired once cerebral embolism has occurred; however, it does not differ in patients with symptomatic versus silent cerebral embolism. Routine computed tomography scans are therefore mandatory due to the high incidence of asymptomatic cerebrovascular embolism--which appears to be equally as dangerous as symptomatic embolism.

Extracellular matrix gene expression correlates to left ventricular mass index after surgical induction of left ventricular hypertrophy

Abstract The cardiac extracellular matrix (ECM) is a dynamic entity maintaining the structural and functional properties of the myocardium. Little is known about alterations in ECM regulation during controlled induction of compensated left ventricular hypertrophy (LVH) using experimental aortic stenosis.Fifteen growing sheep received supra-coronary banding at an age of 7 ± 1 months whereas 10 age-matched sheep served as the control group (C). Explantation of the hearts was performed 8.3 ± 1 months after banding. Gene sequences for sheep matrix metalloproteinase (MMP)-1,-2,-3,-9 and tissue inhibitors (TIMP)-1,-2,-3 were isolated and cloned. Then mRNA and protein gene expression analyses were performed.Concentric LVH with no evidence of heart failure was diagnosed at explantation. Left ventricular mass index (LVMI) was 150 ± 33 g/m2 (LVH) versus 88 ± 23 (C) and 82 ± 21 (baseline) (p < 0.01 versus LVH). Parallel to LVH there was a significant increase in mRNA and protein expression for MMP-1,-2,-3,-9 and for TIMP-1,-2 whereas there was a significant decrease in TIMP-3 gene expression. A close correlation between changes in LVMI and ECM gene expression was found.Compensated LVH goes along with a significant modification of MMP and TIMP gene expression. Alterations in ECM gene expression may be part of the adaptive process during left ventricular remodeling.

Double valve replacement and reconstruction of the intervalvular fibrous body in patients with active infective endocarditis

OBJECTIVES Destruction of the intervalvular fibrous body, though uncommon, occurs due to paravalvular abscess formation following active infective endocarditis. This warrants a highly complex operation involving radical surgical debridement of the intervalvular fibrous body, followed by double valve (aortic and mitral) replacement with patch reconstruction of the anterior mitral annulus, the left ventricular outflow tract and the left atrial roof. The objective of this study was to review the early and mid-term outcomes in patients undergoing this operation. METHODS A total of 25 patients underwent double valve replacement with reconstruction of the intervalvular fibrous body for extensive infective endocarditis between January 1999 and March 2012. The mean age was 64.3 ± 10.5 years. Most of the patients (60%) were in New York Heart Association Class III-IV, 12% and in cardiogenic shock. Associated comorbidities like acute renal insufficiency and cerebrovascular accidents were observed in 40 and 20% of patients, respectively. Twenty patients had previous heart valve surgeries. The logistic EuroSCORE predicted risk of mortality was 55.1 ± 22.9%. RESULTS Overall, 30-day mortality was 32%. Postoperative complications like low cardiac output, stroke and acute renal failure developed in 16, 28 and 56%, respectively. Thirty-two percent of patients required re-exploration for bleeding. Nine patients were alive at a mean follow-up of 406 days (0-8 years). The 2- and 5-year survivals were 37.0 ± 11.1 and 24.6 ± 12.5%, respectively. CONCLUSIONS Double valve replacement with reconstruction of the intervalvular fibrous body for infective endocarditis is a complex, technically challenging operation associated with high perioperative morbidity and mortality. Nevertheless, being the only option available for such complex disease, it should be performed in these patients who, otherwise, face 100% mortality.

Outcome of Aortic Valve Replacement for Active Infective Endocarditis in Patients on Chronic Hemodialysis

BACKGROUND The high risk of morbidity and mortality for patients on hemodialysis who are undergoing cardiac surgery is increased for those with active infective endocarditis (AIE). This retrospective observational single-center study evaluated the impact of chronic hemodialysis on the outcome of aortic valve replacement in patients with aortic AIE. METHODS Data were retrospectively collected for consecutive patients undergoing aortic valve surgery for AIE diagnosed according to modified Duke criteria between October 1994 and January 2011. Characteristics and outcomes of patients receiving preoperative chronic hemodialysis were analyzed. RESULTS Aortic valve AIE was present in 992 patients. Forty-five (4.5%) of the aortic valve AIE patients were receiving long-term hemodialysis preoperatively, 19 of whom (42.2%) had diabetes mellitus. Mean logistic EuroSCORE was 64.2% ± 32.2%. Twenty-four preoperative septic emboli were found in 15 patients. Results of microbiologic cultures were positive in 36 patients, with the major causative organisms identified as Staphylococcus aureus (n = 17) and Enterococcus faecalis (n = 10). Isolated aortic valve replacement was performed in 19 patients (42.2%), and 26 patients (57.8%) underwent concomitant procedures. The mean follow-up was 5.3 ± 5.2 years (range, 0.1 to 17.1 years). Postoperative complications occurred in 30 patients (66.7%). Nineteen patients (42.2%) died within 30 days of surgery, which in 8 patients was attributable to a cardiac cause. CONCLUSIONS In patients receiving chronic hemodialysis who undergo aortic valve replacement for acute AIE, postoperative mortality is high, especially in patients undergoing aortic root replacement or culture-negative AIE.

Preoperative introduction and maintenance immunosuppression therapy of oral-only tacrolimus, mycophenolate mofetil and steroids reduce acute rejection episodes after lung transplantation

OBJECTIVE Immunosuppression therapy in lung transplantation (LTX) remains unsatisfactory due to a high incidence of infection and frequent acute rejection (AR), leading to early onset of the bronchiolitis obliterans syndrome (BOS). The long-term success of LTX is limited by BOS, associated with marked morbidity and mortality. The strongest risk factor for BOS is frequent AR. Decreasing frequent AR episodes might lead to improved long-term survival following LTX. METHODS Despite the introduction of many novel agents, the basis of currently applied protocols remains a calcineurin inhibitor, that is, cyclosporine/tacrolimus (TAC). Eighty-two lung recipients received oral-only administered immunosuppression with oral TAC, mycophenolate mofetil (MMF) and intravenous (IV) methylprednisolone as introduction 2h prior to skin incision. Intra-operatively, patients received additional methylprednisolone prior to unclamping the pulmonary arteries. Postoperatively oral TAC/MMF and prednisolone were continued and trough levels closely monitored (target 8-12 ng ml(-1)). Pulmonary function tests were performed frequently and daily after discharge by means of a self-measuring device (daily forced expiratory volume in 1s (FEV(1))) as the major part of a close follow-up and monitoring programme. Trans-bronchial biopsies were rarely performed. Patient data were collected prospectively and stored in transplantation registries. LTX survival was analysed according to the Kaplan-Meier method. RESULTS The follow-up of the LTX patients through frequent ambulatory care unit visits and close monitoring of the immunosuppressive regimen and the medication response was 100% complete. The mean duration of observation per patient was 1.8 + or - 1.7 years (median 1.4, range: 0.0-6.4 years) and this study included 176.5 patient-related years of follow-up. The 1-, 3- and 5-year survival following LTX was 70%, 60% and 55%, respectively. Eight patients (10%) underwent high-dose intravenous (IV) bolus methylprednisolone treatment and taper for AR. Two additional patients developed BOS more than 4 years following LTX. The AR- and BOS-related mortality was 0% within the 7-year interval of LTX. Alterations in FEV(1) were associated with significant anastomotic airway and infectious complications, requiring frequent bronchoscopic interventions, stenting and laser therapy as well as frequent IV antibiotic treatment. The 30-day and in-hospital mortality of 19.5% was markedly related to primary graft failure and viral infection. Long-term survival was limited predominantly by cytomegalovirus (CMV) infection and sepsis. CONCLUSIONS Our results suggest that a standard immunosuppressive regimen of TAC and MMF orally administered and introduced prior to skin incision for LTX surgery and maintained long-term might reduce the incidence of acute and chronic rejection. Viral infections and not BOS seemed to be the limiting factor of long-term survival.

Experimental Aortic Stenosis and Corresponding Left Ventricular Hypertrophy in Sheep

Left ventricular hypertrophy (LVH) is an independent cardiac risk factor. A simple standard experimental model of inducing LVH for further studies using experimental aortic stenosis in sheep was performed. The aim of this study is to describe animal-specific requirements as well as perioperative therapy, postoperative care, and the use of echocardiography for routine follow-up examinations. Supracoronary aortic banding was performed in 55 female sheep at an age of 6 to 8 months. General anesthesia and an antero-lateral thoracotomy were used. The objective was to achieve pressure gradients of 20 to 30 mm Hg. In addition a 4th intercostal space rib window was created to improve echocardiographic vision. The operations were completed successfully in all animals. Intraoperatively, little severe arrhythmia occurred. During the follow-up interval of 8 +/- 1.3 months, 8 animals died, due to incomplete perforation of the ascending aorta (3), chronic heart failure (2), pericardial cyst (1), and respiratory failure and infection (2). All remaining animals were amenable for further studies. Severe LVH was diagnosed with routine echocardiography on follow-up. Thus, experimental aortic stenosis in sheep is a safe and relatively simple technique to generate stable LVH. Echocardiography is an easy tool for follow-up evaluations. Due to low complication rates, the sheep model is well suited for further research in LVH.

Gender-Based Long-Term Surgical Outcome in Patients with Active Infective Aortic Valve Endocarditis

Background The aim of this observational, single-center study was to evaluate the impact of gender on surgical outcome in patients with active infective endocarditis (AIE) of the aortic valve. Material/Methods Between October 1994 and January 2011, 755 patients (558 men and 297 women) underwent surgery for AIE at the Leipzig Heart Center, Germany, according to the modified Duke criteria. Data were collected before surgery and as the study was ongoing. Gender influence on survival was evaluated (Kaplan-Meier curves). Cox proportional models were used to evaluate gender differences in relation to early mortality (within 30 days) and late mortality (up to 10 years). Results The early mortality rate was 15.0% among men and 23.0% among women, which was statistically significant different (p=0.01). In male patients, variables associated with overall mortality were age (HR 1.63, 95% CI 1.43–1.86; p<0.001), insulin-dependent diabetes mellitus (HR 2.02, 95% CI 1.48–2.75; p<0.001), preoperative low ejection fraction (OR 0.99, 95% CI 0.98–0.99; p=0.002), previous cardiac surgery (OR 1.62, 95% CI 1.22–2.13; p=0.001), preoperative ventilation (OR 1.77, 95% CI 1.14–2.75; p=0.012), preoperative dialysis (OR 1.89, 95% CI 1.20–2.98; p=0.006), NYHA Class IV (OR 1.56, 95% CI 1.12–2.15; p=0.008), and involvement of multiple valves (OR 1.65, 95% CI 1.24–2.19; p=0.001) had a statistically significant influence on the late mortality. Focus identification (OR 1.75, 95% CI 1.08–2.77; p=0.023), involvement of multiple valves (OR 1.52, 95% CI 1.02–2.26; p=0.040), preoperative dialysis (OR 3.65, 95% CI 1.96–6.77; p<0.001), and age (OR 1.53, 95% CI 1.28–1.82; p<0.004) were predictive risk factors for late mortality in women with AIE (OR 3.6, 95% CI 1.5–8.4; p<0.004). Conclusions This study demonstrated distinct gender-based differences in risk of mortality in patients with AIE (who were undergoing surgical treatment) with different early and long-term outcomes.

Tricuspid Valve Surgery in Patients with Isolated Tricuspid Valve Endocarditis: Analysis of Perioperative Parameters and Long-Term Outcomes.

Background The aim of this study was to evaluate the perioperative characteristics and the short‐ and mid‐term outcomes in patients undergoing tricuspid valve (TV) surgery for isolated TV endocarditis. Patients and Methods A total of 56 patients with isolated TV endocarditis underwent TV surgery at a single center between June 1995 and February 2012. Mean age of patients was 53.8 ± 17.1 years, 39 (69.6%) being male. The mean left ventricular ejection fraction was 60.4 ± 13.6% and 13 (23.2%) patients had diabetes mellitus. Average logistic EuroSCORE was 19.4 ± 17.0%. Mean follow‐up was 4.7 ± 3.8 years. Results Microbiological investigations revealed positive blood cultures in 89.1% of patients and positive intraoperative swabs in 51.9%. The most common pathogen (42.9%) isolated was Staphylococcus aureus, followed by coagulase‐negative staphylococcus (17.9%). Discussion A history of intravenous drug abuse (IVDA) was recorded in 11 patients (19.6%), of which 8 patients additionally had hepatitis C. A total of 15 patients (26.8%) had a permanent pacemaker/implantable cardioverter‐defibrillator in situ. TV replacement was performed in 22 patients (39.3%) and TV repair was performed in 34 patients (60.7%). Overall 30‐day mortality was 12.5%. Five‐year survival was 63.9 ± 7.2% (95% confidence interval [CI]: 64.0‐137.5 months). Freedom from reoperation for recurrent TV endocarditis was 91.7 ± 4.0% (95% CI: 152.3‐179.3 months) at 5 years. Conclusion Blood culture is the most important tool to detect the causative pathogen causing IE of TV. The high risk of hepatitis C in patients with IVDA and IE of the TV should be mentioned.