Benefits of rapid deployment aortic valve replacement with a mini upper sternotomy.

BACKGROUND: Surgical aortic valve replacement (AVR) is currently deemed the gold standard of care for patients with severe aortic stenosis. Currently, most AVRs are safely performed through a full median sternotomy approach. With an increasingly elderly and high-risk patient population, major advances in valve technology and surgical technique have been introduced to reduce perioperative risk and post-operative complications associated with the full sternotomy approach, in order to ensure surgical AVR remains the gold standard. For example, minimally invasive approaches (most commonly via mini sternotomy) have been developed to improve patient outcomes. The advent of rapid deployment valve technology has also been shown to improve morbidity and mortality by reducing cardiopulmonary bypass and aortic cross-clamp times, as well as facilitating the use of minimal access approaches. Rapid deployment valves were introduced into our department at the Royal Infirmary of Edinburgh in 2014. The aim of this study is to investigate if utilising the combination of rapid deployment valves and a mini sternotomy minimally invasive approach resulted in improved outcomes in various patient subgroups. METHODS: Over a 3-year period, we identified 714 patients who underwent isolated AVR in our centre. They were divided into two groups: 61 patients (8.5%) were identified who received rapid deployment AVR via J-shaped mini upper sternotomy (MIRDAVR group), whilst 653 patients (91.5%) were identified who received either a full sternotomy (using a conventional prosthesis or rapid deployment valve) or minimally invasive approach using a conventional valve (CONVAVR group). We retrospectively analysed data from our cardiac surgery database, including pre-operative demographics, intraoperative times and postoperative outcomes. Outcomes were also compared in two different subgroups: octogenarians and high-risk patients. RESULTS: Pre-operative demographics showed that there were significantly more female and elderly patients in the MIRDAVR group. The MIRDAVR group had significantly reduced cardiopulmonary bypass (63.7 min vs. 104 min, p = 0.0001) and aortic cross-clamp times (47.3 min vs. 80.1 min, p = 0.0001) compared to the CONVAVR group. These results were particularly significant in the octogenarian population, who also had a reduced length of ICU stay (30.9 h vs. 65.6 h, p = 0.049). In high-risk patients (i.e. logistic EuroSCORE I > 10%), minimally invasive-rapid deployment aortic valve replacement is still beneficial and is also characterized by significantly shorter cardiopulmonary bypass time (69.1 min vs. 96.1 min, p = 0.03). However, post-operative correlations, such as length of ICU stay, become no more significant, likely due to serious co-morbidities in this patient group. CONCLUSION: We have demonstrated that minimally invasive rapid deployment aortic valve replacement is associated with significantly reduced cardiopulmonary bypass and aortic cross-clamp times. This correlation is much stronger in the octogenarian population, who were also found to have significantly reduced length of ICU stay. Our study raises the suggestion that this approach should be utilised more frequently in clinical practice, particularly in octogenarian patients.

The novel use of oral antibiotic monotherapy in prosthetic valve endocarditis caused by Finegoldia magna: a case study.

BACKGROUND: Finegoldia magna, a Gram-positive anaerobic coccus, is part of the human normal microbiota as a commensal of mucocutaneous surfaces. However, it remains an uncommon pathogen in infective endocarditis, with only eight clinical cases previously reported in the literature. Currently, infective endocarditis is routinely treated with prolonged intravenous antibiotic therapy. However, recent research has found that switching patients to oral antibiotics is non-inferior to prolonged parenteral antibiotic treatment, challenging the current guidelines for the treatment of infective endocarditis. CASE PRESENTATION: This case report focuses on a 52-year-old gentleman, who presented with initially culture-negative infective endocarditis following bioprosthetic aortic valve replacement. Blood cultures later grew Finegoldia magna. Following initial intravenous antibiotic therapy and re-do surgical replacement of the prosthetic aortic valve, the patient was successfully switched to oral antibiotic monotherapy, an unusual strategy in the treatment of infective endocarditis inspired by the recent publication of the POET trial. He made excellent progress on an eight-week course of oral antibiotics and was successfully discharged from surgical follow-up. CONCLUSIONS: This case is the 9th reported case of Finegoldia magna infective endocarditis in the literature. Our case also raises the possibility of a more patient-friendly and cost-effective means of providing long-term antibiotic therapy in suitable patients with prosthetic valve endocarditis and suggests that the principles highlighted in the POET trial can also be applicable to post-operative patients after cardiac surgery.

Endovascular approach in chronic aortoiliac disease in patient undergoing coronary artery bypass surgery.

Internal thoracic artery (ITA) is an excellent conduit for coronary artery bypass surgery (CABG). We present a patient with known preoperative aortoiliac disease with anterior collateral pathway who had an indication for elective coronary bypass. The use of ITA in these patients may cause lower limb ischemia. Detecting Winslow's anastomotic pathway before CABG is of utmost importance.

Surgical treatment of atrial septum lipomatous hypertrophy associated with syncopal attacks.

Lipomatous hypertrophy of atrial septum (LHAS) is a rare benign cardiac condition characterized by fatty tissue infiltration located in the atrial septum. We presented a rare case of LHAS resulting in recurrent syncopal attacks.

Pharmacological Neuroprotection in Cardiac Surgery: Effectiveness of Pharmacologic-Preconditioning with Erythromycin.

Regardless of the degree of advances in neuroprotective strategies, and despite the technological progress in neuromonitoring, brain injury still remains the "Achilles' heel" in cardiac surgery. A large number of pharmacological and non-pharmacological therapeutic interventions have been investigated during the last two decades. Recently, both theoretical and experimental findings suggest benefits of pharmacological cerebral protection, although, there is no conclusive evidence of clinical superiority of specific agents that have been applied as neuroprotectants, in human randomized controlled trials. Pre-ischemic conditioning has also been used in an attempt to reduce the incidence of brain injury following cardiac surgery. In light of previous evidence showing that pharmacologic preconditioning with a single dose of erythromycin induces tolerance against transient global cerebral ischemia in rats, we examined whether erythromycin would reduce the number of apoptotic neurons in the neocortex in our acute porcine model of hypothermic circulatory arrest (HCA). Pre-ischemic conditioning with a single dose of the antibiotic erythromycin, applied 12 h before HCA, significantly reduced neuronal injury in the neocortex of the porcine brain, suggesting that cerebral protection may be achieved with erythromycin pharmacological preconditioning in cardiac surgery on an experimental basis. Since erythromycin has been effectively used in clinical practice with few side effects, these findings suggest that it could be a promising candidate for potential clinical neuroprotective strategy.

Diabetes mellitus does not affect the incidence of acute kidney injury after cardiac surgery; a nested case-control study.

BACKGROUND: Acute kidney injury (AKI) after cardiac surgery is a common complication associated with increased mortality. However, the heterogeneity of the definitions used results in high variance of incidence rates in the literature. Data on the effect of diabetes mellitus on AKI incidence in this setting are scarce. We thus aimed to compare the incidence of AKI (defined by the AKIN, RIFLE and KDIGO criteria) in diabetic vs. non-diabetic patients undergoing cardiac surgery. METHODS: This is a nested case-control study from a cohort of patients undergoing cardiac surgery between 1/1/2013 and 30/6/2014 in a single center. Exclusion criteria were: type-1 diabetes, end-stage renal disease, death during surgery and AKI prior to surgery. We identified 199 type-2 diabetic patients and matched them for gender, age and estimated glomerular filtration rate (eGFR) to 199 non-diabetic individuals. The incidence of AKI between the two groups was compared in the total population and in subgroups according to preoperative eGFR. Univariate and multivariate logistic regression analysis were conducted to identify factors associated with AKI. RESULTS: The incidence of AKI was moderately high, but similar between the two study groups (AKIN and KDIGO: 24.1 vs. 23.1 %; p = 0.906, RIFLE: 25.1 vs. 25,1 %; p = 1.000, in diabetics and non-diabetics respectively). A trend towards increased incidence of AKI from eGFR subgroup 1 to subgroup 3a was noted in diabetic patients (p = 0.04). No significant differences were detected between the two study groups within any eGFR subgroup studied. At multivariate analysis, age [per year increase: odds ratio (OR) 1.034, 95 % confidence interval (CI) 1.001-1.068] and duration of cardiopulmonary bypass [per minute increase: OR 1.009 (1.003-1.015)] were associated with AKI. Diabetes was not related to AKI development in regression analysis [OR 1.057 (0.666-1.679)]. CONCLUSIONS: Incidence of AKI after cardiac surgery is high, but diabetes is not a risk factor for AKI. Baseline renal function in diabetics is related inversely to the incidence of AKI. Age and cardiopulmonary bypass duration are independent predictors of cardiac surgery-associated AKI.

Decreased DNA Disruption in the Porcine Neocortex with Erythromycin Preconditioning during Prolonged Hypothermic Circulatory Arrest: Evidence for Neuroprotection.

BACKGROUND AND AIM OF THE STUDY: We have previously reported that the neocortex is selectively vulnerable to injury in an acute porcine model of hypothermic circulatory arrest (HCA) at 18°C. In view of recent evidence showing that pharmacologic preconditioning with a single dose of erythromycin induces tolerance against transient global cerebral ischemia in rats, we hypothesized that erythromycin would reduce the number of apoptotic neurons in the neocortex in an acute porcine model of HCA at 18°C. METHODS: Fourteen piglets underwent 75 min of HCA at 18°C following pretreatment with erythromycin (25 mg/kg, IV) (n = 8) or vehicle (Normal Saline 0.9%) (n = 6), applied 12 hr before arrest. Three served as normal controls. After gradual rewarming to a temperature of 36°C, treatment animals were sacrificed and brains were perfusion-fixed and cryopreserved. Neuronal apoptosis after HCA was observed morphologically with hematoxylin and eosin staining, and characterized by in situ DNA fragmentation using terminal deoxynucleotidyl-transferase-mediated biotin-dUTP nick end-labeling (TUNEL) histochemistry. RESULTS: Pre-ischemic conditioning with a single dose of the antibiotic erythromycin reduced neuronal apoptosis in the neocortex of the porcine brain. TUNEL-positive cells indicating DNA fragmentation and neuronal injury were significantly greater in the neocortex of animals treated with 18°C HCA (2.55 ± 1.17) compared to animals undergoing HCA after erythromycin preconditioning (1.76 ± 0.91) (p ≤ 0.001). CONCLUSIONS: These results suggest that cerebral protection during HCA may be achieved with erythromycin pharmacological preconditioning in the porcine model.

Pericardial fat is strongly associated with atrial fibrillation after coronary artery bypass graft surgery†.

OBJECTIVES: Recent evidence suggests that pericardial fat may represent an important risk factor for cardiovascular disease because of its unique properties and its proximity to cardiac structures. It has been reported that pericardial fat volume (PFV) is associated with atrial fibrillation (AF). The purpose of this study was to investigate the association between PFV and new-onset AF following coronary artery bypass graft surgery (CABG). METHODS: PFV was measured using computed tomography in 83 patients with coronary artery disease scheduled to undergo elective isolated on-pump CABG. Patient characteristics, medical history and perioperative variables were prospectively collected. Any documented episode of new-onset postoperative AF until discharge was defined as the study end point. RESULTS: Twenty-eight patients (33.7%) developed postoperatively AF during hospital stay. There was no significant difference in demographics and comorbidities among patients that maintained sinus rhythm (SR) and their AF counterparts. In univariate analysis, patients with postoperative AF had significantly more pericardial fat compared with SR patients (195 ± 80 ml vs 126 ± 47 ml, P = 0.0001). Larger left atrial diameter was also associated with postoperative AF (42.4 ± 6.9 mm vs 39.3 ± 4.8 mm, P = 0.017). Additionally, the prebypass use of calcium channel-blocking agents was independently associated with a lower incidence of postoperative AF, confirmed also by multivariate analysis (P = 0.035). In multivariate logistic regression analysis, PFV was the strongest independent variable associated with the development of postoperative AF (odds ratio: 1.018, 95% confidence interval: 1.009-1.027, P = 0.0001). The best discriminant value assessed by receiver operating characteristic analysis was 129.5 ml (sensitivity 86% and specificity 56%). CONCLUSIONS: PFV is strongly associated with AF following CABG, independently of many traditional risk factors. Our findings suggest that PFV may represent a novel risk factor for postoperative AF. However, the role of pericardial fat in AF mechanism needs to be further delineated.

Atypical pattern of lung involvement in pacemaker endocarditis.

Pacemaker endocarditis has a high rate of morbidity and mortality and is associated with substantial health-care cost. To maximize the effectiveness of treatment, diagnosis of pacemaker endocarditis should be made as early as possible. Medical treatment alone is not successful, and the removal of the entire artificial pacing system is often required. We present a case of a female patient with a permanent transvenous pacemaker, recurring episodes of fever and chills, general malaise, and a computed tomography image of a solitary tumor-like lesion indicating pneumonia. The symptoms subsided with empirical antibiotics but without improvement in the radiologic images. A wedge resection of the lesion by thoracotomy was performed, revealing a necrotic lung lesion compatible with pulmonary infarct. Transesophageal echocardiography showed a mass that was adherent to the pacemaker lead. The therapeutic approach consisted of surgical removal of the complete pacing system along with long-term antibiotic therapy and implantation of a new device with an epicardial lead. Serial follow-up echocardiograms for a 1-y period did not show any recurrence, and the subsequent course was uneventful.

'Early' post-cardiotomy chylopericardium and the imaging value of magnetic resonance thoracic-ductography.

Isolated chylopericardium is a rare postoperative complication after cardiac surgery. A delay in diagnosis or an inappropriate management can lead to serious consequences. The treatment, which may either be conservative or surgical, is controversial and it depends on the duration and volume of effusion. We report a case of chylopericardium after atrial septal defect repair in a young woman. The patient was treated initially with total parenteral nutrition for 10 days. After drainage diminished, low fat diet containing medium chain triglyceride was instituted. Postoperatively, the role of magnetic resonance thoracic ductography was important for the assessment of the treatment strategy.

Noninvasive ventilation for post-pneumonectomy severe hypoxemia.

ARDS remains a lethal complication after major lung resections. The reported mortality ranges from 50% to 100%, with increased incidence and mortality rates in pneumonectomy patients. The pathogenesis of early ARDS is still not fully understood, and the majority of patients will require mechanical ventilation. A review of the literature reveals that the role of noninvasive ventilation (NIV) in ARDS after lung resection is unclear, in contrast to its well established benefits in other types of respiratory failure. NIV is a technique of augmenting alveolar ventilation delivered by face mask, without introducing an endotracheal tube. NIV may reduce the need for endotracheal mechanical ventilation and improve clinical outcome in patients with acute respiratory failure after lung resection, avoiding complications related to intubation. We present a case of early ARDS following left-sided pneumonectomy, where bi-level positive airway pressure ventilation prompted a successful outcome.