Minimally Invasive Direct Coronary Artery Bypass Grafting: Sixteen Years of Single-Center Experience.

Background: Coronary artery disease is a major cause of death globally. Minimally invasive direct coronary artery bypass (MIDCAB), using a small left anterior thoracotomy, aims to provide a less invasive alternative to traditional procedures, potentially improving patient outcomes with reduced recovery times. Methods: This retrospective, non-randomized study analyzed 310 patients who underwent MIDCAB between July 1999 and April 2022. Data were collected on demographics, clinical characteristics, operative and postoperative outcomes, and follow-up mortality and morbidity. Statistical analysis was conducted using IBM SPSS, with survival curves generated via the Kaplan-Meier method. Results: The cohort had a mean age of 63.3 ± 10.9 years, with 30.6% females. The majority of surgeries were elective (76.1%), with an average operating time of 129.7 ± 35.3 min. The median rate of intraoperative blood transfusions was 0.0 (CI 0.0-2.0) Units. The mean in-hospital stay was 8.7 ± 5.5 days, and the median ICU stay was just one day. Early postoperative complications were minimal, with a 0.64% in-hospital mortality rate. The 6-month and 1-year mortalities were 0.97%, with a 10-year survival rate of 94.3%. There were two cases of perioperative myocardial infarction and no instances of stroke or new onset dialysis. Conclusions: The MIDCAB approach demonstrates significant benefits in terms of patient recovery and long-term outcomes, offering a viable and effective alternative for patients suitable for less invasive procedures. Our results suggest that MIDCAB is a safe option with favorable survival rates, justifying its consideration in high-volume centers focused on minimally invasive techniques.

Polyphosphate uses mTOR, pyrophosphate, and Rho GTPase components to potentiate bacterial survival in Dictyostelium.

IMPORTANCE: Although most bacteria are quickly killed after phagocytosis by a eukaryotic cell, some pathogenic bacteria escape death after phagocytosis. Pathogenic Mycobacterium species secrete polyP, and the polyP is necessary for the bacteria to prevent their killing after phagocytosis. Conversely, exogenous polyP prevents the killing of ingested bacteria that are normally killed after phagocytosis by human macrophages and the eukaryotic microbe Dictyostelium discoideum. This suggests the possibility that in these cells, a signal transduction pathway is used to sense polyP and prevent killing of ingested bacteria. In this report, we identify key components of the polyP signal transduction pathway in D. discoideum. In cells lacking these components, polyP is unable to inhibit killing of ingested bacteria. The pathway components have orthologs in human cells, and an exciting possibility is that pharmacologically blocking this pathway in human macrophages would cause them to kill ingested pathogens such as Mycobacterium tuberculosis.

Starvation Induces Extracellular Accumulation of Polyphosphate in Dictyostelium discoideum to Inhibit Macropinocytosis, Phagocytosis, and Exocytosis.

Dictyostelium discoideum is a soil-dwelling unicellular eukaryote that accumulates extracellular polyphosphate (polyP). At high cell densities, when the cells are about to overgrow their food supply and starve, the corresponding high extracellular concentrations of polyP allow the cells to preemptively anticipate starvation, inhibit proliferation, and prime themselves to begin development. In this report, we show that starved D. discoideum cells accumulate cell surface and extracellular polyP. Starvation reduces macropinocytosis, exocytosis, and phagocytosis, and we find that these effects require the G protein-coupled polyP receptor (GrlD) and two enzymes, Polyphosphate kinase 1 (Ppk1), which is required for synthesizing intracellular polyP, cell surface polyP, and some of the extracellular polyP, and Inositol hexakisphosphate kinase (I6kA), which is required for cell surface polyP and polyP binding to cells, and some of the extracellular polyP. PolyP reduces membrane fluidity, and we find that starvation reduces membrane fluidity; this effect requires GrlD and Ppk1, but not I6kA. Together, these data suggest that in starved cells, extracellular polyP decreases membrane fluidity, possibly as a protective measure. In the starved cells, sensing polyP appears to decrease energy expenditure from ingestion, and decrease exocytosis, and to both decrease energy expenditures and retain nutrients.

Starvation induces extracellular accumulation of polyphosphate in Dictyostelium discoideum to inhibit macropinocytosis, phagocytosis, and exocytosis.

Dictyostelium discoideum is a soil-dwelling unicellular eukaryote that accumulates extracellular polyphosphate (polyP). At high cell densities, when the cells are about to overgrow their food supply and starve, the corresponding high extracellular concentrations of polyP allow the cells to preemptively anticipate starvation, inhibit proliferation, and prime themselves to begin development. In this report, we show that starved D. discoideum cells accumulate cell surface and extracellular polyP. Starvation reduces macropinocytosis, exocytosis, and phagocytosis, and we find that these effects require the G protein-coupled polyP receptor (GrlD) and two enzymes, Polyphosphate kinase 1 (Ppk1), which is required for synthesizing intracellular polyP, cell surface polyP, and some of the extracellular polyP, and Inositol hexakisphosphate kinase (I6kA), which is required for cell surface polyP and polyP binding to cells, and some of the extracellular polyP. PolyP reduces membrane fluidity, and we find that starvation reduces membrane fluidity, and this effect requires GrlD and Ppk1 but not I6kA. Together, these data suggest that in starved cells, extracellular polyP decreases membrane fluidity, possibly as a protective measure. In the starved cells, sensing polyP appears to decrease energy expenditure from ingestion, and decrease exocytosis, to both decrease energy expenditures and retain nutrients.

Pre-surgery optimization of patients' expectations to improve outcome in heart surgery: Study protocol of the randomized controlled multi-center PSY-HEART-II trial.

The PSY-HEART-I trial indicated that a brief expectation-focused intervention prior to heart surgery improves disability and quality of life 6 months after coronary artery bypass graft surgery (CABG). However, to investigate the clinical utility of such an intervention, a large multi-center trial is needed to generalize the results and their implications for the health care system. The PSY-HEART-II study aims to examine whether a preoperative psychological intervention targeting patients' expectations (EXPECT) can improve outcomes 6 months after CABG (with or without heart valve replacement). EXPECT will be compared to Standard of Care (SOC) and an intervention providing emotional support without targeting expectations (SUPPORT). In a 3-arm multi-center randomized, controlled, prospective trial (RCT), N = 567 patients scheduled for CABG surgery will be randomized to either SOC alone or SOC and EXPECT or SOC and SUPPORT. Patients will be randomized with a fixed unbalanced ratio of 3:3:1 (EXPECT: SUPPORT: SOC) to compare EXPECT to SOC and EXPECT to SUPPORT. Both psychological interventions consist of 2 in-person sessions (à 50 minute), 2 phone consultations (à 20 minute) during the week prior to surgery, and 1 booster phone consultation post-surgery 6 weeks later. Assessment will occur at baseline approx. 3-10 days before surgery, preoperatively the day before surgery, 4-6 days later, and 6 months after surgery. The study's primary end point will be patients' illness-related disability 6 months after surgery. Secondary outcomes will be patients' expectations, subjective illness beliefs, quality of life, length of hospital stay and blood sample parameters (eg, inflammatory parameters such as IL-6, IL-8, CRP). This large multi-center trial has the potential to corroborate and generalize the promising results of the PSY-HEART-I trial for routine care of cardiac surgery patients, and to stimulate revisions of treatment guidelines in heart surgery.

Mid-term Outcome of the Edge-To-Edge Mitral Valve Repair Via Aortic Outflow Tract in High-Risk Patients.

The edge-to-edge mitral valve repair technique, invented by Alfieri and colleagues, introduced valve repair as a treatment option for patients with complex diseases where standard annuloplasty and related repair techniques are insufficient, due to annular calcification and patient frailty. We retrospectively evaluated the results of a transaortic edge-to-edge mitral valve repair (Alfieri stitch) in high-risk patients who were undergoing aortic valve replacement. From February, 2012 to December, 2017, 43 patients underwent transaortic edge-to-edge mitral valve repair with concomitant aortic valve replacement at a single institution. Preoperative and postoperative echocardiograms were compared. Home telephone follow up was conducted and postoperative morbidity was examined, including the need for reoperation, stroke and cardiac arrhythmia. 30-day and long-term survival rates were also determined. Mitral regurgitation (MR) was graded semi-quantitatively as 0 (trace and/or none), mild (1), moderate (2) or moderate to severe (3-4). The patients were 74 ± 7.8 years old. 65% of the patients were male. Mean cardiopulmonary bypass time was 115 ± 37 minutes and mean cross-clamp time was 71 ± 23 minutes. There was a significant improvement in preoperative vs postoperative median MR grade (2 (IQR 2-3) vs 0 (IQR 0-1); P = 0.05). Follow-up transthoracic echocardiograms in 29 patients obtained at a median of 9 months' (range 3 - 19 months') and in 16 patients at a median of 34 months' postoperatively (range 21 - 53 months') showed mild (1 (IQR 1-2)) grade of mitral regurgitation. 30-day survival was 98%. Long term survival at 12 and 24 months' were 88% and 81% respectively. Mitral valve reoperation was conducted in 1 patient (2%), who was suffering of endocarditis. Stroke occurred in 2 patients (7%). Cardiac arrhythmia was observed in 15 patients (35%). 8 patients (19%) suffered from atrial fibrillation and 7 patients (16%) displayed atrioventricular blockage. 10 patients (23%) could be treated conservatively and 5 patients (12%) needed implantation of a pacemaker. Transaortic edge-to-edge mitral valve repair can be safely performed during aortic valve replacement in high-risk patients and improves even long-term MR grade. Postoperative cardiac arrhythmia occurs frequently. 66% of them could be treated successfully by conservative procedures.

Coronary artery bypass grafts to chronic occluded right coronary arteries.

Background: The benefit of revascularizing chronically occluded coronary arteries remains debatable, and available long-term outcome reports are sparse. Current guidelines recommend revascularization of chronically occluded arteries only in patients with myocardial ischemia and/or symptoms associated with angina. We investigated outcome of patients with total chronic occlusion of the right coronary artery (RCA) receiving coronary artery bypass grafting (CABG) surgery with and without revascularization of the RCA. Methods: We retrospectively analyzed all patients with chronically occluded RCAs receiving CABG with (group 1 = RCA-CABG; n = 487) and without (group 2 = No-RCA-CABG; n = 100) revascularization of the RCA. In total, 587 patients with complete follow-up of a minimum of 6 years were included (92%). Results: In total, 82% in group 1 versus 86% in group 2 were male (P = .38). European System for Cardiac Operative Risk Evaluation II was comparable between both groups (4.35 ± 7.09% vs 4.80 ± 5.77%, P = .56) with no major differences regarding preoperative characteristics between groups. Patients in group 1 received 3.24 ± 0.79 distal anastomoses, whereas group 2 received 2.45 ± 0.83 distal anastomoses (P < .001). Although in-hospital mortality was comparable (2.9% in group 1 vs 5.0% in group 2, P = .27), long-term survival was significantly better in group 1 (P = .002). No difference in the incidence of further major adverse cardiac and cerebrovascular events was found. Conclusions: Patients with a chronically occluded RCA undergoing CABG who did not receive an RCA graft showed a significantly reduced long-term survival. Given the herein presented data, revascularization of chronically occluded right arteries during CABG should be recommended whenever technically feasible.

Echocardiographic guided, transatrial closure of a patent foramen ovale.

BACKGROUND: The management of an incidental patent foramen ovale found during planned cardiac surgery remains a challenge, and current guidelines are not helpful. Although evidence is accumulating, that closure of an incidental found patent foramen ovale might be beneficial, especially in planned off-pump procedures, the diagnosis of a formerly unknown patent foramen ovale with the patient on the operation table has vast consequences by making it necessary to switch to on pump, bi-caval cannulation for patent foramen ovale closure. We therefore developed a technique for transatrial closure of a patent foramen ovale, guided by transesophageal echocardiography. RESULTS: We have performed this surgery in 9 patients. None of them had a previously diagnosed patent foramen ovale. Mean age was 74 (±5) years, Operation time was 175 min (± 34 min), Clamp time 35 min (± 16 min) and Cardiopulmonary bypass time 80 (±17 min). Mortality was 0%. Periprocedural transesophageal echocardiography revealed closure of the patent foramen ovale in all cases. CONCLUSION: We report a new surgical method for transoesophageal echocardiography controlled closure of a patent foramen ovale without the need for an atriotomy. This new technique is especially useful for the closure of patent foramen ovale in the setting of on-pump and off-pump coronary artery bypass graft surgeries alike.

Total Arterial Revascularization with Radial Artery and Internal Thoracic Artery T-Grafts Is Associated with Superior Long-Term Survival in Patients Undergoing Coronary Artery Bypass Grafting.

AIMS: Compelling evidence encourages the use of the radial artery (RA) as the second arterial graft in coronary artery bypass grafting (CABG). However, its long-term benefits remain disputed. We sought to evaluate long-term outcome and survival by comparing patients receiving RAs with those receiving venous grafts to a single internal thoracic artery (ITA). METHODS: We analyzed 345 patients undergoing primary multivessel CABG and conducted a 13-year long follow-up. In all, 187 patients received the RA and the left ITA as T-graft; 158 patients received saphenous veins complementing a single ITA. We performed propensity-score matching on 81 pairs to balance treatment selection and confounders. RESULTS: Patients receiving RAs were younger and less likely to be female or to have pulmonary hypertension, impaired renal function, or left main coronary disease.At 30 days, they showed significantly lower unadjusted mortality and renal impairment. Unadjusted long-term survival was superior in the RA group, even after propensity-score matching. We found that RA use protected from late mortality. CONCLUSIONS: Using the RA and the left ITA as T-graft is associated with a significant long-term survival benefit in patients undergoing CABG. It may display a promising alternative to conventional use of a single ITA supplemented by saphenous veins.

Higher-Order Structure in Amorphous Poly(ethylene terephthalate)/Graphene Nanocomposites and Its Correlation with Bulk Mechanical Properties.

Graphene of two different aspect ratios, A f, was melt mixed with poly(ethylene terephthalate) (PET) to form amorphous PET/graphene composites with less than 5% crystallinity. The higher-order structure and mechanical properties of poly(ethylene terephthalate) (PET) in these composites were investigated using techniques such as differential scanning calorimetry and dynamic mechanical analysis, whereas transmission electron microscopy, melt rheology, and electrical conductivity were used to study the graphene dispersion. A decrease in heat capacity changes, ΔC p, of PET in nanocomposites at the glass transition temperature, T g, without T g change suggests that a rigid amorphous fraction (RAF) of PET was formed at the PET/graphene interface. The stiffening effect of graphene below 1 wt % loading is quite small in the glassy state region and independent of the A f of graphene. Above 2 wt %, graphene forms a mechanical percolation network with the RAF of PET and the PET chains are geometrically restricted by the incorporation of graphene with a high A f, resulting in an unexpectedly higher modulus of nanocomposites both below and above T g.

Early surgical myocardial revascularization in non-ST-segment elevation acute coronary syndrome.

BACKGROUND: In non-ST-elevation myocardial infarction (NSTEMI) there is no consensus regarding optimal time point for coronary artery bypass grafting (CABG). Recent findings suggest that long-term outcomes are improved in early-revascularized NSTEMI patients. However, it has been stated that early surgery is associated to increased operative risk. In this study, we wanted to elucidate if early CABG in non-ST-elevation acute coronary syndrome can be performed safely. METHODS: We performed a monocentric-prospective observational study within a 2-year interval. A total of 217 consecutive patients (41 female, age 68.9±10.2, ES II 6.62±8.56) developed NSTEMI and underwent CABG. Patients were divided into two groups according to the time point of coronary artery bypass after symptom onset (group A: <72 h; group B: >72 h). Endpoints included 6-month mortality and incidence of MACE (death, stroke or re-infarction). RESULTS: There were no differences regarding mortality between both groups (30 days: group A 2.4% vs. group B 3.7%; P=0.592; 6 months: 8.4% vs. 6.0%; P=0.487). Incidence of MACE in the 6-month follow-up was also similar in both groups (group A: 9.6% vs. 9.7%, P=0.982). Regression analysis revealed as independent risk factors for mortality in the entire cohort ES II OR 1.045 (95% CI: 1.004-1.088). ES II remained an independent prognostic factor in group A OR 1.043 (95% CI: 1.003-1.086) and group B OR 1.032 (95% CI: 1.001-1.063). CONCLUSIONS: Early revascularized patients showed a higher level of illness. However, results of early CABG were comparable to those following delayed revascularization. Moreover, EuroSCORE II was determined as independent risk factors for mortality.

Rupture of the Free Left Ventricular Wall: A Novel Approach for Reconstruction.

Background A rupture of the free wall of the left ventricle is a rarely seen complication of myocardial infarction and represents an absolute cardiac emergency. Case Description We hereby present a case of a 64-year-old patient with a rupture of the free left ventricular wall. The patient was treated in an emergent operation with a novel reconstruction method of the left ventricular wall and was discharged 30 days after the initial operation. Conclusion Left ventricular free wall rupture is rarely described in the literature, which might be because of high mortality in underdiagnosed cases. Therefore, early imaging by echo or computed tomography (CT) is essential for detecting this dangerous condition. Once diagnosed, urgent surgery is mandatory to save the life of the patient.

Minimally Invasive Mitral Valve Surgery in Re-Do Cases-The New Standard Procedure?

BACKGROUND: Minimally invasive mitral valve surgery (MIMVS) is superior to "classical" mitral valve surgery via a sternotomy regarding wound healing and postoperative pain. It is however a more challenging procedure. Patients' preference is leading clearly toward minimally invasive approaches, and surgeons are driven by upcoming new technologies in interventional procedures such as the MitraClip. Especially in re-do cases, the access via right mini-thoracotomy, as previously non-operated situs, is a possible advantage over a re-sternotomy. We therefore retrospectively analyzed our result regarding MIMVS in re-do cases at our institute. METHODS: From January 2011 and June 2016, 33 operations were MIMVS re-do procedures. Mean age was 60 years (±16 years), and 51% were male. RESULTS: Sixty-one percent were elective cases, 29% were urgent cases, and 9% were emergency operations. Operation times, cardiopulmonary bypass (CPB) times, and clamp times were 235 minutes (±51 min), 149 minutes (±42 min), and 62 minutes (±45min), respectively. Mitral valve repair and replacement was performed in 24% (n = 8) and 76% (n = 25), respectively. Overall in-hospital mortality, apoplexy, and re-operation rates (all for bleeding) were 0% (n = 0), 3% (n = 1), and 9% (n = 3). New onset of dialysis was required in two (6%) patients. Two (6%) patients developed superficial wound infection. Overall intensive care unit (ICU) and hospital stay was 3 days (±4 days) and 15 days (±7 days), respectively. CONCLUSION: MIMVS for re-do cases can be performed with minimal mortality and morbidity and therefore represents a safe alternative to conventional mitral valve surgery in cardiac re-do operations. However, postoperative morbidity is highly dependent on preoperative patient status.

Local Anesthetics delivered through Pleural Drainages improve Pain and Lung Function after Cardiac Surgery.

OBJECTIVE: Pleural tubes after coronary artery bypass graft (CABG) surgery usually cause pain resulting interalia in an impact of postoperative breathing. Therefore, the influence of intrapleural lidocaine application through special double-lumen chest tubes with respect to pain relief and lung function was investigated and compared with placebo. METHODS: In this study, 40 patients who underwent CABG got intrapleural injection either with 2% lidocaine (n = 20) or placebo (0.9% saline solution) (n = 20) on the first 2 days after surgery. Pain was measured by pain intensity numeric rating scale (NRS) (0 = no pain; 10 = the most intense pain) and lung function by portable spirometer. RESULTS: On the first postoperative day (POD1), mean pain reduction was NRS 1.9 for the lidocaine group with an improvement of the forced expiratory volume in 1 second (FEV1) of 0.51 L. Similar results were shown on the second postoperative day (POD2) with a decreased pain level of mean NRS 1.65 and an FEV1 improvement of 0.26 L. In comparison, results of the placebo group showed no significant pain reduction, neither on the POD1 (NRS 0.35; p = 0.429) nor on the POD2 (NRS 0.55; p = 0.159). Also, there was no significant influence of FEV1 after placebo on the POD1 (FEV1 = 0.048 L; p = 0.70) or on the POD2 (FEV1 = 0.0135 L; p = 0.925). CONCLUSION: Intrapleural application of lidocaine is a safe and feasible method to reduce drainage-related pain and improving lung function after CABG.

Novel mouse model of cardiopulmonary bypass.

OBJECTIVES: Cardiopulmonary bypass (CPB) is an essential component of many cardiac interventions, and therefore, there is an increasing critical demand to minimize organ damage resulting from prolonged extracorporeal circulation. Our goal was to develop the first clinically relevant mouse model of CPB and to examine the course of extracorporeal circulation by closely monitoring haemodynamic and oxygenation parameters. METHODS: Here, we report the optimization of device design, perfusion circuit and microsurgical techniques as well as validation of physiological functions during CPB in mice after circulatory arrest and reperfusion. Validation of the model required multiple blood gas analyses, and therefore, this initial report describes an acute model that is incompatible with survival due to the need of repetitive blood draws. RESULTS: Biochemical and histopathological assessment of organ damage revealed only mild changes in the heart and lungs and signs of the beginning of acute organ failure in the liver and kidneys. CONCLUSIONS: This new CPB mouse model will facilitate preclinical testing of therapeutic strategies in cardiovascular diseases and investigation of CPB in relation to different insults and pre-existing comorbidities. In combination with genetically modified mice, this model will be an important tool to dissect the molecular mechanisms involved in organ damage related to extracorporeal circulation.

Surgical treatment of coronary artery aneurysms.

INTRODUCTION: Coronary artery aneurysms (CAA) are rare. We present our experience with the surgical treatment of patients with CAAs. METHODS: Between March 2000 and October 2016, 15 patients with CAA underwent surgery. RESULTS: Mean age of patients was 60 ± 16 years and 47% (n = 7) were male. Kawasaki syndrome was present in two (13%) patients and 7% (n = 1) patients had Marfan syndrome. Isolated CAAs were found in 73% (n = 11) and involvement of multiple vessels was present in 27% (n = 4) of patients. Coronary arteries (CA) affected by aneurysms were: 19% (n = 4) left main stem, 33% (n = 7) left anterior descending, 14% (n = 3) left circumflex, and 33% (n = 7) right coronary artery. The majority of patients (93%, n = 14) were operated on pump with a mean cross-clamp time of 51 ± 23 min. 53% (n = 8) of patients received total arterial CA bypass grafting, while the remaining patients (47%, n = 7) received venous ± internal thoracic artery grafts. Resection/ligation of CAA was performed in 27% (n = 4) of patients. In-hospital mortality was 0% (n = 0). Follow-up was complete for 100% of patients and comprised a total of 80 patient-years. During follow-up, only one patient (7%) required re-intervention. CONCLUSION: Surgical treatment of CAA has good short- and long-term results.

Long-term results of the Mitroflow aortic pericardial bioprosthesis in over 800 patients: limited durability and mechanisms of dysfunction.

OBJECTIVES: The Mitroflow aortic pericardial bioprosthesis was widely employed in the past. However, some authors have recently reported early structural valve deterioration (SVD) of the Mitroflow LA/LXA model. Thus, we reviewed our experience with the Mitroflow bioprosthesis and studied the risk factors for SVD and mortality. METHODS: Records of patients who underwent aortic valve replacement with a Mitroflow bioprosthesis between November 2005 and January 2015 were retrospectively evaluated with Kaplan-Meier, Cox-regression and multistate analysis. Only patients with a complete clinical follow-up were included in the study. Average follow-up was 45 months and ended on 1 April 2016. RESULTS: Between November 2005 and January 2015, among the 916 patients undergoing aortic valve replacement with the Mitroflow prosthesis at our Institution, the 832 (90.8%) patients with follow-up information were included into the study. Fifty-two (6.2%) patients developed SVD (stenosis, n = 38; regurgitation, n = 7; mixed, n = 7). Freedom from SVD was 95.4% and 67.9%, at 5 and 9 years, respectively, without differences after stratification according to the prosthesis model ( P = 0.87) and prosthesis size ( P = 0.70). At the multivariable analysis, increasing age was identified as a protective factor against SVD (hazard ratio = 0.94, P < 0.001). Twenty (38.4%) patients with SVD underwent redo aortic valve replacement. At 5 and 9 years, survival was 64.5% and 43.1%, repectively. According to the multistate analysis, the fraction of patients living with degenerated valves at 9 years was 10.0%; 7.1% died following degeneration. CONCLUSIONS: The LA/LXA Mitroflow model showed limited long-term durability. Degenerated prostheses showed more stenosis than regurgitation. Patient age played an important role in the development of SVD.

In Vitro Evaluation of Inflow Cannula Fixation Techniques in Left Ventricular Assist Device Surgery.

The therapy of terminal heart failure with left ventricular assist devices has become a standard in cardiac surgery. Yet the surgical implantation technique is not standardized and differs from center to center. Complications associated with left ventricular assist device (LVAD) inflow cannula placement are thrombosis, suction events, and flow disturbances. Within this in vitro study we aimed to investigate if the fixation technique of the sewing ring has an impact on the position of the inflow cannula. For this in vitro study the HeartMate III LVAD (Thoratec Corporation, Pleasanton, CA, USA) was used. In five sessions, two approaches were considered for coring of the ventricle for LVAD inflow cannula insertion: "sew-then-core" and "core-then-sew." In the "sew-then-core" technique, the sewing cuff is first affixed to the heart, usually with 8-16 interrupted pledgeted mattress sutures. Subsequently, a cylindrical knife is used to resect a cylindrical core of myocardium to permit cannula insertion. In the "core-then-sew" technique, the sequence is reversed such that the knife is used before the suture ring is affixed. When the "sew-then-core" technique is used, the mattress sutures may be placed with full-thickness bites that penetrate the endocardium (i.e., transmural stitching) or partial-thickness bites that do not penetrate the endocardium (i.e., epicardial stitching). When the "core-then-sew" technique is used, the suture is passed fully into the ventricular lumen and fed back through the cored hole, at which point the needle may be reinserted into the freshly cored myocardium such that it exits the epicardium (i.e., transmural stitching with back stitch) or not (i.e., transmural stitching without back stitch). These four different sewing ring fixation suturing techniques were tested by experienced surgeons to affix the sewing ring: transmural stitching, epicardial stitching, transmural stitching with back stitch, and transmural stitching without back stitch. The sewing ring was sewed onto a silicone dummy designed to simulate the left ventricle with standard 2-0 Ethibond sutures (Ethicon, Somerville, NY, USA). Afterward, the dummies were measured and documented via photography. In addition, porcine hearts were used to simulate the suturing techniques in a physiological setting. The setting of the inflow cannula is substantially influenced by the fixation method of the sewing ring. Epicardial stitching showed the best results with stable cannula fixation, minimal gap around the cannula and no contact between the sutures and sewing ring with blood. The method of transmural stitching without back stitch showed the worst results by creating the biggest epithelial gap between inflow cannula and tissue as well as proving the biggest surface for blood contact between sewing ring and sutures. In general, both "sew-then-core" techniques resulted in a greater degree of apposition between the cuff and epicardial tissue. Within the study we revealed that the surgical fixation of the sewing ring has a significant impact on the inflow cannula stability, position, and tissue apposition in LVAD implantation surgery. Epicardial stitching of the sewing ring provides the best results in order to prevent suction events as well as thrombosis formation.

Right-Sided Heart Failure and Extracorporeal Life Support in Patients Undergoing Pericardiectomy for Constrictive Pericarditis: A Risk Factor Analysis for Adverse Outcome.

Background Right ventricular failure is a life-threatening postoperative complication after pericardiectomy. We conducted a retrospective study with a special emphasis on right ventricular failure. Methods Between June 1997 and September 2011, 69 patients underwent surgical pericardiectomy at our center. Mean age was 59 ( ± 15.5) years, and 49 (71%) patients were male. Causes of constrictive pericarditis included idiopathic (52%, n = 36), tuberculosis (9%, n = 6), postcardiotomy (12%, n = 8), radiation (4%, n = 3), renal insufficiency (12%, n = 8), and autoimmune disease (12%, n = 8). Concomitant cardiac surgery was performed in 33 (48%) patients. Results In-hospital mortality rate was 14% (10/69 patients). Extracorporeal membrane oxygenation (ECMO) was necessary in 8 (12%) cases because of right (n = 7) or biventricular (n = 1) failure. Statistical analysis showed a significant correlation between early mortality and the following preoperative variables: postcardiotomy (p = 0.049), radiation (p = 0.009), pleural effusion (p = 0.012), ascites (p = 0.039), hepatic congestion (p = 0.023), absence of calcification on X-ray (p = 0.041), tricuspid valve insufficiency (TI, p < 0.001), and low cardiac index (p = 0.003). Diuretic usage (p = 0.044), peripheral edema (p = 0.050), low voltage (p = 0.027), dip-plateau sign (p = 0.027), elevated GGT (p < 0.001), and decreased serum protein (p < 0.001) correlated with ECMO implantation. Binary logistic regression identified pleural effusion (OR = 16.2, 95% CI = 1.4-191.5), moderate/severe TI (OR = 28.8, 95% CI = 2.7-306.8) and low cardiac index (OR = 25.3, 95% CI = 2.0-315.6) as preoperative independent risk factors for early mortality, whereas elevated GGT (OR = 28.3, 95% CI = 2.4-329.2) and decreased protein (OR = 24.7, 95% CI = 1.8-343.7) could predict right ventricular failure with the need for ECMO. Conclusion We recommend nondelayed ECMO support in case of significant postoperative right-sided heart failure. High-risk patients might benefit from elective pre- or intraoperative ECMO implantation.

Does the surgeon's experience have an impact on outcome after total arterial revascularization with composite T-grafts? A risk factor analysis.

OBJECTIVES: When composite T-grafting is performed, total arterial revascularization (TAR) can be accomplished with only two grafts. There is the belief that composite grafting poses a risk of graft failure due to its single inflow via the left internal thoracic artery (LITA). High surgical quality is essential for left internal thoracic artery preparation, T-grafting and length estimation. We investigated whether the surgeon's experience influences postoperative outcome. METHODS: We analysed the data of 1080 consecutive patients (88% male, age: 62 ± 9 years) who underwent composite T-grafting between 1996 and 2011 in our institution. Patients were operated on either by experienced surgeons (Group A) or by surgeons early on in their career (Group B). Primary end-points were mortality, myocardial ischaemia, graft dysfunction and low cardiac output syndrome. Secondary end-points were persistent neurologic deficits (PNDs), blood transfusions and re-thoracotomy. Logistic regression analysis was performed to reveal independent risk factors for adverse outcome. RESULTS: Patients in Group B had a lower logistic EuroSCORE (2.8 vs 2.3%; P < 0.05), longer operative times (cross-clamp time: 41 ± 11 vs 47 ± 14 min; P < 0.001) and received less anastomoses (3.2 ± 0.7 vs 3.1 ± 0.7, P = 0.005). Mortality was low in both groups (Group A 0.6% vs Group B 0.4%; P = 1.0). Myocardial ischaemia occurred in 2.3% (Group A) and 2.5% (Group B; P = 0.82). Graft dysfunction was seen in 0.6% (Group A) and 1.4% (Group B; P = 0.25). Incidence of postoperative low cardiac output syndrome was comparable (Group A 1.4% vs Group B 0.7%; P = 0.53). Both groups showed similar incidence of secondary end-points (persistent neurologic deficit: Group A 2.9 vs 3.2% in Group B; P = 0.84; re-thoracotomy: 1.6% in Group A vs 1.8% in Group B, P = 1.0). Blood transfusions were more common in Group B (P = 0.005). Less surgical experience could only be identified as an independent risk factor for blood transfusion (P = 0.001). CONCLUSIONS: Total arterial revascularization with composite T-grafts can be performed safely by surgeons with different surgical experience. Despite differences in surgical performance parameters (e.g. operation times, blood transfusions), complication rates were extremely low, irrespective of the surgeon's operative experience. Surgeons can be introduced to these procedures in an early phase of training.