Metabolic profiling of aortic stenosis and hypertrophic cardiomyopathy identifies mechanistic contrasts in substrate utilization.

Aortic stenosis (AS) and hypertrophic cardiomyopathy (HCM) are distinct disorders leading to left ventricular hypertrophy (LVH), but whether cardiac metabolism substantially differs between these in humans remains to be elucidated. We undertook an invasive (aortic root, coronary sinus) metabolic profiling in patients with severe AS and HCM in comparison with non-LVH controls to investigate cardiac fuel selection and metabolic remodeling. These patients were assessed under different physiological states (at rest, during stress induced by pacing).

Arteriovenous fistula creation in a patient without a pulse: Vascular access in patients with left ventricular assist devices.

Left ventricular assist devices are used in heart failure patients as bridge to transplantation or increasingly as a destination therapy. These patients frequently have renal dysfunction and many reach end-stage renal failure. If haemodialysis is required, minimization of infection risk is essential.

Multicentre double-blind randomized controlled trial of perhexiline as a metabolic modulator to augment myocardial protection in patients with left ventricular hypertrophy undergoing cardiac surgery.

Objectives: Patients undergoing cardiac surgery require adequate myocardial protection. Manipulating myocardial metabolism may improve the extent of myocardial protection. Perhexiline has been shown to be an effective anti-anginal agent due to its metabolic modulation properties by inhibiting the uptake of free fatty acids into the mitochondrion, and thereby promoting a more efficient carbohydrate-driven myocardial metabolism.

The role of HIFs in ischemia-reperfusion injury.

The reduction or cessation of the blood supply to an organ results in tissue ischemia. Ischemia can cause significant tissue damage, and is observed as a result of a thrombosis, as part of a disease process, and during surgery. However, the restoration of the blood supply often causes more damage to the tissue than the ischemic episode itself.

The effect of perhexiline on myocardial protection during coronary artery surgery: a two-centre, randomized, double-blind, placebo-controlled trial.

Objectives: Perhexiline is thought to modulate metabolism by inhibiting mitochondrial carnitine palmitoyltransferase-1, reducing fatty acid uptake and increasing carbohydrate utilization. This study assessed whether preoperative perhexiline improves markers of myocardial protection in patients undergoing coronary artery bypass graft surgery and analysed its effect on the myocardial metabolome.

Methods: In a prospective, randomized, double-blind, placebo-controlled trial, patients at two centres were randomized to receive either oral perhexiline or placebo for at least 5 days prior to surgery.

Clinical outcomes of Carbomedics Top Hat valve with a robust follow-up system.

Aim: Late failure of bioprosthetic valves may limit their use in patients < 60 years. The superior hemodynamic performance offered by the Carbomedics Top Hat supraannular valve enables greater effective orifice areas to be achieved. The aim of this study was to assess the clinical outcomes of this valve, using a robust follow-up system.

Relationship between plasma, atrial and ventricular perhexiline concentrations in humans: insights into factors affecting myocardial uptake.

Aim: Little is known regarding the steady-state uptake of drugs into the human myocardium. Perhexiline is a prophylactic anti-anginal drug which is increasingly also used in the treatment of heart failure and hypertrophic cardiomyopathy. We explored the relationship between plasma perhexiline concentrations and its uptake into the myocardium.

The European Association for Cardio-Thoracic Surgery (EACTS) database: an introduction.

Objectives: Continuous monitoring of surgical outcomes through benchmarking and the identification of best practices has become increasingly important. A structured approach to data collection, coupled with validation, analysis and reporting, is a powerful tool in these endeavours. However, inconsistencies in standards and practices have made comparisons within and between European countries cumbersome.

The new EuroSCORE II does not improve prediction of mortality in high-risk patients undergoing cardiac surgery: a collaborative analysis of two European centres.

Objectives: Prediction of operative risk in adult patients undergoing cardiac surgery remains a challenge, particularly in high-risk patients. In Europe, the EuroSCORE is the most commonly used risk-prediction model, but is no longer accurately calibrated to be used in contemporary practice. The new EuroSCORE II was recently published in an attempt to improve risk prediction.

A systematic review of risk prediction in adult cardiac surgery: considerations for future model development.

Objectives: Risk prediction in adult patients undergoing cardiac surgery remains inaccurate and should be further improved. Therefore, we aimed to identify risk factors that are predictive of mortality, stroke, renal failure and/or length of stay after adult cardiac surgery in contemporary practice.

Methods: We searched the Medline database for English-language original contributions from January 2000 to December 2011 to identify preoperative independent risk factors of one of the following outcomes after adult cardiac surgery: death, stroke, renal failure and/or length of stay.

Subtle changes in renal function are associated with differences in late survival following adult cardiac surgery.

Objectives: To determine the predictors of post-operative renal function following adult cardiac surgery, and to assess the influence of this on late survival.

Methods: Prospectively collected data were analysed on 8032 patients who underwent coronary artery bypass grafting, valve surgery or combined procedures from 1 January 1998 until 31 December 2008, who did not require preoperative renal replacement therapy. The estimated glomerular filtration rate (eGFR) was calculated by the Modification of Diet in Renal Disease formula accounting for ethnicity pre-operatively, post-operatively on the fourth post-operative day, and the post-operative nadir based upon the peak post-operative creatinine within 30 days of surgery.

Contemporary outcomes of urgent coronary artery bypass graft surgery following non-ST elevation myocardial infarction: urgent coronary artery bypass graft surgery consistently outperforms Global Registry of Acute Coronary Events predicted survival.

Objectives: The Global Registry of Acute Coronary Events (GRACE) registry reported that the in-hospital risk of death from non-ST elevation myocardial infarction (NSTEMI) is 5%, with an 11% mortality by 6 months. Prospective Registry of Acute Ischaemic Syndromes in the UK demonstrated that the overall risk of death from NSTEMI over 4 years is 25%. In GRACE, while 28% of patients received percutaneous intervention, only 10% received coronary artery bypass graft (CABG).

Changes in cardiac substrate transporters and metabolic proteins mirror the metabolic shift in patients with aortic stenosis.

In the hypertrophied human heart, fatty acid metabolism is decreased and glucose utilisation is increased. We hypothesized that the sarcolemmal and mitochondrial proteins involved in these key metabolic pathways would mirror these changes, providing a mechanism to account for the modified metabolic flux measured in the human heart. Echocardiography was performed to assess in vivo hypertrophy and aortic valve impairment in patients with aortic stenosis (n = 18).

Glucose-insulin-potassium reduces the incidence of low cardiac output episodes after aortic valve replacement for aortic stenosis in patients with left ventricular hypertrophy: results from the Hypertrophy, Insulin, Glucose, and Electrolytes (HINGE) trial.

Background: Patients undergoing aortic valve replacement for critical aortic stenosis often have significant left ventricular hypertrophy. Left ventricular hypertrophy has been identified as an independent predictor of poor outcome after aortic valve replacement as a result of a combination of maladaptive myocardial changes and inadequate myocardial protection at the time of surgery. Glucose-insulin-potassium (GIK) is a potentially useful adjunct to myocardial protection.

Reduced negative surface charge on arterial endothelium explains accelerated atherosclerosis in type 2 diabetic patients.

Reduced endothelial surface charge markedly increases the rate of LDL uptake into blood vessels. Previous work in the streptozotocin diabetic rat reported reduced endothelial surface charge. We compared endothelial surface charge density in internal mammary artery rings from patients with type 2 diabetes (n = 12) and from non diabetic patients undergoing coronary artery bypass grafting, and observed a substantial (52%) reduction in the former.

Patient-prosthesis mismatch in patients with aortic stenosis undergoing isolated aortic valve replacement does not affect survival.

Background: Data suggest that patient-prosthesis mismatch (PPM) adversely effects late survival after aortic valve replacement (AVR). This study examined the incidence and implications of PPM in patients undergoing isolated AVR.

Methods: Prospectively collected data on patients undergoing isolated AVR for aortic stenosis between January 1, 1997 and December 31, 2007 were analyzed.

Mild renal dysfunction predicts in-hospital mortality and post-discharge survival following cardiac surgery.

Objectives: To assess the impact of preoperative renal dysfunction on in-hospital mortality and late survival outcome following adult cardiac surgery.

Methods: Prospectively collected data were analysed on 7621 consecutive patients not requiring preoperative renal-replacement therapy, who underwent CABG, valve surgery or combined procedures from 1/1/98 to 1/12/06. Preoperative estimated glomerular filtration rate was calculated using Cockcroft-Gault formula.

Bleeding in cardiac surgery: the use of aprotinin does not affect survival.

Objective: The antifibrinolytic drug aprotinin has been the most widely used agent to reduce bleeding and its complications in cardiac surgery. Several randomized trials and meta-analyses have demonstrated it to be effective and safe. However, 2 recent reports from a single database have implicated the use of aprotinin as a risk for postoperative complications and reduced long-term survival.

Patient-prosthesis mismatch does not affect survival following aortic valve replacement.

Objective: Patient-prosthesis mismatch (PPM) has been reported to increase perioperative mortality and reduce postoperative survival in patients undergoing aortic valve replacement (AVR). We analysed the effect of PPM at values predicting severe mismatch on survival following AVR in our unit.

Methods: Prospectively collected data on 1481 consecutive patients who had undergone AVR with or without coronary artery revascularisation between 1997 and 2005 were analysed.