Percutaneous Closure of an Iatrogenic Intracardiac Shunt in Treating Torrential Tricuspid Regurgitation.

A patient presented with severe right heart failure due to a large LV-to-RA shunt with left-to-right shunting and torrential tricuspid regurgitation 6-weeks following surgical sub-aortic stenosis resection. Retrograde delivery of an Occlutech ventricular septal defect device produced instantaneous resolution of shunt, reduction in tricuspid regurgitation, and impressive diuresis of 28 kg.

Long-term performance of an external stent for saphenous vein grafts: the VEST IV trial.

BACKGROUND: Externally stenting saphenous vein grafts reduces intimal hyperplasia, improves lumen uniformity and reduces oscillatory shear stress 1 year following surgery. The present study is the first to present the longer-term (4.5 years) performance and biomechanical effects of externally stented saphenous vein grafts. METHODS: Thirty patients previously implanted with the VEST external stent in the randomized, within-patient-controlled VEST I study were followed up for adverse events; 21 of these were available to undergo coronary angiography and intravascular ultrasound. RESULTS: Twenty-one stented and 29 nonstented saphenous vein grafts were evaluated by angiography and ultrasound at 4.5 ± 0.3 years. Vein graft failure rates were comparable between stented and nonstented grafts (30 and 23% respectively; p = 0.42). All failures were apparent at 1 year except for one additional nonstented failure at 4.5 years. In patent vein grafts, Fitzgibbon perfect patency remained significantly higher in the stented versus nonstented vein grafts (81 and 48% respectively, p = 0.002), while intimal hyperplasia area (4.27 mm2 ± 1.27 mm2 and 5.23 mm2 ± 1.83 mm2 respectively, p < 0.001) and thickness (0.36 mm ± 0.09 mm and 0.42 mm ± 0.11 mm respectively, p < 0.001) were significantly reduced. Intimal hyperplasia proliferation correlated with lumen uniformity and with the distance between the stent and the lumen (p = 0.04 and p < 0.001 respectively). CONCLUSIONS: External stenting mitigates saphenous vein graft remodeling and significantly reduces diffuse intimal hyperplasia and the development of lumen irregularities 4.5 years after coronary artery bypass surgery. Close conformity of the stent to the vessel wall appears to be an important factor. TRIAL REGISTRATION: NCT01415245 . Registered 11 August 2011.

Multi-centre prospective internal and external evaluation of the Brompton Harefield Infection Score (BHIS).

BACKGROUND: Previously, we reported that the Brompton Harefield Infection Score (BHIS) accurately predicts surgical site infection (SSI) after coronary artery bypass grafting (CABG). The BHIS was developed using two-centre data and stratifies SSI risk into three groups based on female gender, diabetes or HbA1c > 7.5%, body mass index ≥ 35, left ventricular ejection fraction < 45% and emergency surgery. The purpose of this study was to prospectively evaluate BHIS internally as well as externally. METHODS: Multi-centre prospective evaluation involving three tertiary centres took place between October 2012 and November 2015. SSI was classified using the Public Health England protocol. Receiver operating characteristic (ROC) curves assessed predictive accuracy. RESULTS: Across the four hospital sites, 168 of 4308 (3.9%) CABG patients had a SSI. Categorising the hospitals by BHIS score revealed that 65% of all patients were low risk (BHIS 0-1), 26% were medium risk (BHIS 2-3) and 8% were high risk (BHIS ≥ 4). The area under the ROC curve was in the range of 0.702-0.785. Overall area under the ROC curve was 0.709. CONCLUSIONS: BHIS provides a novel, internally and externally evaluated score for a patient's risk of SSI after CABG. It enables clinicians to focus on strategies to prospectively identify high-risk patients and improve outcomes.

A Randomized Trial of External Stenting for Saphenous Vein Grafts in Coronary Artery Bypass Grafting.

BACKGROUND: External stents inhibit saphenous vein graft (SVG) intimal hyperplasia in animal studies. We investigated whether external stenting inhibits SVG diffuse intimal hyperplasia 1 year after coronary artery bypass graft surgery. METHODS: Thirty patients with multivessel disease undergoing coronary artery bypass graft surgery were enrolled. In addition to an internal mammary artery graft, each patient received one external stent to a single SVG randomly allocated to either the right or left coronary territories; and one or more nonstented SVG served as the control. Graft patency was confirmed at the end of surgery in all patients. The primary endpoint was SVG intimal hyperplasia (mean area) assessed by intravascular ultrasonography at 1 year. Secondary endpoints were SVG failure, ectasia (>50% initial diameter), and overall uniformity as judged by Fitzgibbon classification. RESULTS: One-year follow-up angiography was completed in 29 patients (96.6%). All internal mammary artery grafts were patent. Overall SVG failure rates did not differ significantly between the two groups (30% stented versus 28.2% nonstented SVG, p = 0.55). The SVG mean intimal hyperplasia area, assessed in 43 SVGs, was significantly reduced in the stented group (4.37 ± 1.40 mm(2)) versus nonstented group (5.12 ± 1.35 mm(2), p = 0.04). In addition, stented SVGs demonstrated marginally significant improvement in lumen uniformity (p = 0.08) and less ectasia (6.7% versus 28.2%, p = 0.05). There was some evidence that ligation of side branches with metallic clips increased SVG failure in the stented group. CONCLUSIONS: External stenting has the potential to improve SVG lumen uniformity and reduce diffuse intimal hyperplasia 1 year after coronary artery bypass graft surgery.

Heparin induced thrombocytopenia in a patient with factor V Leiden following cardiac surgery.

We report a patient who died as a result of heparin induced thrombocytopenia (HIT) and arterial thromboses following cardiac surgery. The onset was three days after exposure to low molecular weight heparin on the eighth postoperative day. The patient was heterozygous for the factor V Leiden mutation. We have reviewed 15 patients previously diagnosed as HIT on clinical and laboratory criteria and found an incidence of 6.7% (1/15) activated protein C resistance. This second patient had a pulmonary embolus and HIT after only three days exposure to low molecular weight heparin. We postulate that factor V Leiden hastens the onset and magnifies the severity of HIT.

Regional ventricular dynamics during acute coronary occlusion: a comparison of invasive with non-invasive echocardiographic markers to detect and quantify myocardial ischaemia-observations made during off-pump coronary surgery.

OBJECTIVES: To investigate the performance of non-invasive markers used in stress echocardiography to detect the presence and depth of myocardial ischaemia. We therefore sought to compare these non-invasive markers during acute coronary occlusion in humans. METHODS: 27 patients with stable angina and normal LV cavity size were studied during off-pump coronary artery bypass grafting to the left anterior descending coronary artery using transoesophageal echocardiography and simultaneous high fidelity LV pressure. Regional power development of the anterior wall was plotted throughout the cardiac cycle, allowing the measurement of its time course, peak value and time integral (intrinsic work). Regional effective myocardial work was calculated and its reduction during acute occlusion was used as the invasive standard for ischaemic dysfunction. RESULTS: In all patients acute coronary occlusion led to a delay in the onset of regional wall thickening which persisted after aortic valve closure. These time intervals of myocardial thickening had the highest qualitative concordance with the gold standard of a fall in effective work. Regression models identified three significant predictors of the depth of myocardial ischaemia; the interval from Q wave to the onset of regional thickening, duration of post-ejection thickening and peak thickening rate. Objective wall thickening and thinning rates were not significant predictors. CONCLUSIONS: The regional timing of myocardial thickening and peak thickening rate accurately predicted the presence and indicated the depth of local ischaemia during acute coronary occlusion. These markers may complement subjective wall motion scores aimed at predicting the presence of epicardial coronary artery disease. CONDENSED ABSTRACT: We compared non-invasive markers commonly used in stress echocardiography using measurements of the fall in regional myocardial work with coronary occlusion as a standard. 27 patients were studied using transoesophageal echocardiography and simultaneous high fidelity left ventricular pressure during off-pump coronary surgery. Delayed myocardial thickening had the highest qualitative concordance with the gold standard of a fall in effective work, while regression models identified three significant predictors; the interval Q wave to the onset of regional thickening, duration of post-ejection thickening and peak thickening rate. These markers may complement current non-invasive indices of ischaemia during clinical stress testing.

A validated simple model to predict coexistent coronary disease in patients undergoing mitral valve surgery.

OBJECTIVE: The primary limitation of the American Heart Association/American College of Cardiology guidelines is specificity. To improve the selection process, we proposed a simple additive model including age (1 point for every 5 years above 50), male sex (2 points), hypercholesterolemia (2 points), angina (3 points), and electrocardiographic evidence of ischemia (3 points). We recommend screening angiography at 3 or more points. This model was previously derived from 359 patients at Papworth Hospital. METHODS: The validation cohort was a consecutive series of patients who underwent mitral valve surgery at the Royal Brompton Hospital. Preoperative coronary angiography reports were obtained, and coronary disease was defined as luminal narrowing of 50% in 2 or more views. Sensitivities and specificities were calculated for the American Heart Association/American College of Cardiology criteria, the simple additive model, and a logistic regression model. Receiver operating characteristic curves were used to validate accuracy and compare discrimination with logistic regression. RESULTS: From 1998 through 2003, angiographic details were available for 342 (86%) of 396 patients who underwent mitral valve surgery. The sensitivity and specificity of the American Heart Association/American College of Cardiology guidelines were 100% and 5%, respectively; those of the simple additive model were 91% and 44%, respectively; and those of logistic regression were 93% and 41%, respectively. The receiver operating characteristic areas for the simple additive and logistic regression model were 0.78 (95% confidence interval, 0.73-0.84) and 0.80 (95% confidence interval, 0.74-0.85), respectively. CONCLUSIONS: This is the third independent cohort to highlight the poor specificity of the American Heart Association/American College of Cardiology guidelines. Although high sensitivity is achieved, the cost is the majority of patients requiring screening angiography. Our validated simple model improved the specificity and selection; however, this was achieved at the expense of decreased sensitivity.

Two-chamber intracardiac mesothelioma.

Primary intracardiac malignant mesotheliomas are extremely rare and carry a very poor prognosis. We present such a case where the lesion encompassed two chambers, the left atrium and ventricle, with no pericardial involvement. Initial echocardiography mimicked a myxoma, and urgent surgical intervention was required in view of significant cardiorespiratory compromise. To the best of our knowledge this is the first case of a primary two-chamber intracardiac malignant sarcomatoid mesothelioma.

Re-do aortic valve replacement: does a previous homograft influence the operative outcome?

BACKGROUND AND AIM OF THE STUDY: Late reoperation for failed aortic homograft is widely regarded as a high-risk procedure. A review is presented of the authors' experience of redo-aortic valve replacement (re-do AVR) examining factors which affect, and whether a previous aortic homograft replacement influences, operative outcome. METHODS: A retrospective review was conducted of consecutive re-do AVR performed at the authors' institution between 1998 and 2002. RESULTS: During the study period, 178 patients (125 males, 53 females; mean age 52.4 years; range: 16-85 years) underwent re-do AVR. The group included first-time (72%), second-time (20%), and more than third-time re-do AVR (8%). Forty-six patients (26%) received a homograft (group I), and 132 (74%) a stented biological/mechanical valve (group II). The two groups were matched for baseline clinical characteristics and operative variables. The type of explanted valve, and preoperative and operative variables, were analyzed using univariate and multivariate models. Primary outcome was defined as 30-day mortality, and secondary outcome as postoperative complications. The overall 30-day mortality was 12.3%, but was much lower (4.5%) for elective isolated and multiple re-do AVR. Univariate analysis showed significant predictors of 30-day mortality to be: age >65 years (p = 0.02); renal dysfunction (p = 0.005); preoperative unstable status (p = 0.03); preoperative NYHA class III/IV dyspnea (p = 0.02); non-elective operation (p = 0.01); preoperative arrhythmia (p = 0.005); history of chronic obstructive pulmonary disease (COPD) (p = 0.002); preoperative cardiogenic shock (p = 0.03); impaired left ventricular ejection fraction (LVEF) <50% (p = 0.04); and other valvular procedure(s) performed simultaneously (p = 0.01). In a multivariate analysis, the only significant predictors of 30-day mortality were impaired LVEF (p = 0.03) and a history of COPD (p = 0.007). Group I patients had a significantly shorter mean hospital stay (10.2+/-5.9 versus 14.1+/-12.5 days; p = 0.009), but there were no significant differences between groups in terms of postoperative complications. CONCLUSION: A previous aortic homograft replacement was not associated with an increased operative risk at the time of re-do AVR. A history was COPD was an important predictor of 30-day mortality, and this finding requires further investigation.

Chronic stable ischaemia protects against myocyte damage during beating heart coronary surgery.

OBJECTIVES: Many patients with coronary artery disease demonstrate chronic resting ischaemic myocardial dysfunction. We have investigated whether this ischaemia influences the myocardial damage caused by the period of coronary occlusion involved in beating heart surgery. METHODS: Thirty-three patients with chronic stable angina and normal left ventricular ejection fraction were studied. To make our model clinically appropriate, we included patients with a wide range of ischaemic times, ages and in a subset of 10 patients a surgical preconditioning protocol. Myocyte injury was assessed from venous Troponin T release measured on days 1, 2, and 3. We used intraoperative transoesophageal M mode echocardiograms and simultaneous high-fidelity left ventricular pressure to assess whether patients were demonstrating the functional effects of ischaemia (asynchronous regional contraction with reduced mechanical function). RESULTS: Patients demonstrated the functional effects of resting ischaemia and 17 did not. Patients with resting ischaemia had lower preoperative values of regional peak power and work and all three variables increased significantly with surgery. Venous Troponin T levels at 48 and 72 h postoperatively were lower in those with preoperative resting ischaemia (median (interquartile range) 0.13 (0.08-0.20) vs 0.21 (0.13-0.69) for 48 h and 0.10 (0.08-0.19) vs 0.26 (0.12-0.51) for 72 h). Stepwise multiple linear regression of total postoperative troponin release (measured as the area under the curve of troponin release) demonstrated two independent determinants (R squared for model 0.40): longer ischaemic time, and increasing values of cycle efficiency. The surgical ischaemic preconditioning protocol and preoperative collaterals were not independent determinants. CONCLUSIONS: In patients with chronic coronary artery disease, stable preoperative ischaemia may thus represent a naturally occurring form of myocardial protection, whose presence reduces Troponin T release after beating heart surgery. This protection is different in nature from classical ischaemic preconditioning.

Off-Pump Coronary Artery Bypass (OPCAB) surgery reduces risk-stratified morbidity and mortality: a United Kingdom Multi-Center Comparative Analysis of Early Clinical Outcome.

OBJECTIVE: Off-Pump Coronary Artery Bypass (OPCAB) surgery is gaining more popularity worldwide. The aim of this United Kingdom (UK) multi-center study was to assess the early clinical outcome of the OPCAB technique and perform a risk-stratified comparison with the conventional Coronary Artery Bypass Grafting (CABG) using the Cardio-Pulmonary Bypass (CPB) technique. METHODS: Data were collected on 5,163 CPB patients from the database of the National Heart and Lung institute, Imperial College, University of London, and on 2,223 OPCAB patients from eight UK cardiac surgical centers, which run established OPCAB surgery programs. All patients had undergone primary isolated CABG for multi-vessel disease through a midline sternotomy approach, between January 1997 and April 2001. Postoperative morbidity and mortality were compared between the CPB and OPCAB patients after adjusting for case-mix. The mortality of the OPCAB patients was also compared, using risk stratification, to the mortality figures reported by the Society of Cardiothoracic Surgeons of Great Britain and Ireland (SCTS) based on 28,018 patients in the national database who were operated on between January 1996 and December 1999. RESULTS: Morbidity and mortality were significantly lower in the OPCAB patients compared with the CPB patients and the UK national database of CABG patients, over the same period of time, after adjusting for case-mix. CONCLUSIONS: This study demonstrates that risk stratified morbidity and mortality are significantly lower in OPCAB patients than CPB patients and patients in the UK national database.

Is the use of cardiopulmonary bypass for multivessel coronary artery bypass surgery an independent predictor of operative mortality in patients with ischemic left ventricular dysfunction?

BACKGROUND: l Coronary artery bypass grafting for patients with ischemic left ventricular dysfunction (ILVD) remains superior to medical therapy in terms of long-term survival. Recently, off-pump coronary artery bypass surgery has been shown to be very promising in achieving functional improvements with favorable operative mortality in this challenging group of patients. The aim of this study was to assess the risk factors responsible for operative mortality in this group of patients. METHODS: The records of 305 consecutive ILVD patients, who underwent primary isolated coronary artery bypass grafting for multivessel disease at The National Heart and Lung Institute, Imperial College, University of London, between January 1999 and January 2002, were reviewed retrospectively. Patients were considered to have ILVD if they had a left ventricular ejection fraction of 0.30 or less on preoperative coronary angiography. One hundred six patients were operated on using the off-pump coronary artery bypass surgery technique, and 199 patients were operated on using the conventional coronary artery bypass grafting technique with cardiopulmonary bypass. RESU;TS: Seven (6.6%) patients died in the off-pump coronary artery bypass surgery group, whereas 28 (14.1%) patients died in the cardiopulmonary bypass group (p = 0.05). Univariate analysis of all the preoperative characteristics was performed to identify the potential predictors of mortality in the whole group of ILVD patients. Potential predictors of mortality included symptom status (stable/unstable), chronic obstructive airway disease, dyspnea grade III and IV on the New York Heart Association classification, intravenous nitrates, preoperative use of intraaortic balloon pump, ventricular tachycardia or ventricular fibrillation, body surface area less than 2, and cardiopulmonary bypass. Only ventricular tachycardia or ventricular fibrillation was proved to act as an independent predictor of operative mortality in this group of ILVD patients, with an odds ratio of 29.6 (95% confidence interval, 8.9 to 98). CONCLUSIONS: This study showed that using cardiopulmonary bypass for multivessel coronary artery bypass grafting in patients with ILVD was not proved to act as an independent predictor of operative mortality.