Simon Kendall

Coronary Artery Bypass Grafting is Associated With Excellent Long-Term Survival and Quality of Life: A Prospective Cohort Study

BACKGROUND We investigated the long-term outcome of coronary artery bypass grafting both in terms of survival and quality of life. METHODS Ten-year postsurgery survival was collated on patients undergoing coronary artery bypass grafting from 1994 to 1996, and quality of life was assessed using EQ-5D and a quality-of-life thermometer. We analyzed data from 1,180 patients. Mean age was 61 years, and 79% had triple-vessel disease. RESULTS Thirty-day mortality was 3.3% (1.8% elective). Mean time to censorship for survivors was 9.9 years (range, 8.1 to 12.3 years). Ten-year survival was 66% across all patients, 70% for elective patients. Ten-year cardiac survival was 82%. Percutaneous intervention was required in 25 patients in the subsequent 10 years (2%), and only 4 required redo coronary artery bypass grafting (0.3%); 59% of patients reported no angina, and 88% of patients had grade II angina or better. Of 621 patients who were assessed for quality of life at 10 years, 530 (85%) had a quality of life within a 95% confidence interval of the score found in the general population with similar age. Poor quality of life was reported in 91 patients (14.7%). Significant predictors of poor long-term quality of life were current smoking, Canadian Cardiovascular Society grade III or IV, redo operation, female sex, diabetes, peripheral vascular disease, more than 2 days in intensive care, and chronic obstructive pulmonary disease. Twenty-five percent of patients with poor EQ-5D outcome had grade IV angina. Interestingly, age did not correlate with poor outcome, and administration of blood, arterial revascularization, left mainstem disease, or cross-clamp fibrillation had no impact on survival or outcome. CONCLUSIONS Coronary artery bypass grafting is associated with excellent 10-year survival and quality of life.

A comparison of outcomes between bovine pericardial and porcine valves in 38 040 patients in England and Wales over 10 years

OBJECTIVES Biological valves are the most commonly implanted prostheses for aortic valve replacement (AVR) surgery in the UK. The aim of this study was to compare performance of porcine and bovine pericardial valves implanted in AVR surgery with respect to survival and reintervention-free survival in a retrospective observational study. METHODS Prospectively collected clinical data for all first-time elective and urgent AVRs with or without concomitant coronary artery bypass graft (CABG) surgery performed in England and Wales between April 2003 and March 2013 were extracted from the National Institute for Cardiovascular Outcomes Research database. Patient life status was tracked from the Office for National Statistics. Time-to-event analyses were performed using log-rank tests and Cox proportional hazards regression modelling with random effects/grouped frailty for responsible cardiac surgeons. RESULTS A total of 38,040 patients were included (64.9% bovine pericardial; 35.1% porcine). Patient characteristics were similar between the groups. The median follow-up was 3.6 years. There was no statistically significant difference in survival (P = 0.767) (the 10-year survival rates were 49.0 and 50.3% in the bovine pericardial and porcine groups, respectively) or reintervention-free survival. The adjusted hazard ratio for porcine valves was 0.98 (95% confidence interval 0.93-1.03). Sensitivity analysis in small valve sizes showed no difference in reintervention-free survival. After adjustment, there was some evidence of a protective effect for porcine valves in relatively younger patients (P = 0.075). CONCLUSIONS There were no differences in reintervention-free survival between bovine pericardial and porcine valves used in first-time AVR ± CABG up to a maximum of 10 years.

Dynamic prediction modeling approaches for cardiac surgery

Background— The calibration of several cardiac clinical prediction models has deteriorated over time. We compare different model fitting approaches for in-hospital mortality after cardiac surgery that adjust for cross-sectional case mix in a heterogeneous patient population. Methods and Results— Data from >300 000 consecutive cardiac surgery procedures performed at all National Health Service and some private hospitals in England and Wales between April 2001 and March 2011 were extracted from the National Institute for Cardiovascular Outcomes Research clinical registry. The study outcome was in-hospital mortality. Model approaches included not updating, periodic refitting, rolling window, and dynamic logistic regression. Covariate adjustment was made in each model using variables included in the logistic European System for Cardiac Operative Risk Evaluation model. The association between in-hospital mortality and some variables changed with time. Notably, the intercept coefficient has been steadily decreasing during the study period, consistent with decreasing observed mortality. Some risk factors, such as operative urgency and postinfarct ventricular septal defect, have been relatively stable over time, whereas other risk factors, such as left ventricular function and surgery on the thoracic aorta, have been associated with lower risk relative to the static model. Conclusions— Dynamic models or periodic model refitting is necessary to counteract calibration drift. A dynamic modeling framework that uses contemporary and available historic data can provide a continuously smooth update mechanism that also allows for inferences to be made on individual risk factors. Better models that withstand the effects of time give advantages for governance, quality improvement, and patient-level decision making.

Septic Pulmonary Emboli Caused by a Hemodialysis Catheter

We present an unusual complication caused by a dialysis catheter inserted through the internal jugular vein into the central venous system. The 49-year-old male patient developed a right atrial thrombus, which became infected with Staphylococcus aureus, resulting in septic pulmonary embolism and septicemic shock. The thrombus was excised on cardiopulmonary bypass. The patient made an uneventful recovery.

Coronary bypass grafting using crossclamp fibrillation does not result in reliable reperfusion of the myocardium when the crossclamp is intermittently released: a prospective cohort study

BackgroundCross-clamp fibrillation is a well established method of performing coronary grafting, but its clinical effect on the myocardium is unknown. We sought to measure these effects clinically using the Khuri Intramyocardial pH monitor.Methods50 episodes of cross-clamping were recorded in 16 patients who underwent CABG with crossclamp-fibrillation. An Intramyocardial pH probe measured the level of acidosis in the anterior and posterior myocardium in real-time. The pH at the start and end of each period of cross-clamping was recorded.ResultsIt became very apparent that the pH of some patients recovered quickly while others entirely failed to recover. Thus the patients were split into 2 groups according to whether the pH recovered to above 6.8 after the first crossclamp-release (N = 8 in each group). Initial pH was 7.133 (range 6.974–7.239). After the first period of crossclamping the pH dropped to 6.381 (range 6.034–6.684). The pH in recoverers prior to the second XC application was 6.990(range 6.808–7.222) compared to only 6.455 (range 6.200–6.737) in patients whose myocardium did not recover (P < 0.0005). This finding was repeated after the second XC release (mean pH 7.005 vs 6.537) and the third (mean pH 6.736 vs 6.376). However prior to separation from bypass the pH was close to the initial pH in both groups (7.062 vs 7.038).ConclusionCrossclamp fibrillation does not result in reliable reperfusion of the myocardium between periods of crossclamping.

Giant cell myocarditis of the left atrium

Here we describe an unusual case of giant cell myocarditis (GCM) found in the left atrial appendage. Giant cell myocarditis is a rare entity in itself, while isolated left atrial GCM has only been reported on a few occasions. We describe a patient who underwent mitral valve replacement for rheumatic mitral stenosis and excision of a grossly abnormal, thickened, and enlarged left atrial appendage. Histological examination confirmed the presence of GCM.

Activity and outcomes for aortic valve implantations performed in England and Wales since the introduction of transcatheter aortic valve implantation

OBJECTIVES The first transcatheter aortic valve implantation (TAVI) in England and Wales was performed in 2007. This study presents the subsequent national activity and outcomes for both TAVI and aortic valve replacement (AVR). METHODS Data for all AVR and TAVI procedures between January 2006 and December 2012 in England and Wales were included. The number of procedures, patient characteristics, in-hospital and 30-day mortality, postoperative length of stay (PLOS) and survival were analysed separately for: isolated AVR; AVR + coronary artery bypass graft (CABG) surgery; AVR + other surgery and TAVI. RESULTS The number of TAVIs increased from 66 in 2007 (0.8% of all implants) to 1186 in 2012 (10.9% of all implants). AVR activity also increased over the study period. TAVI patients were older and had a higher mean logistic EuroSCORE than all AVR groups. The 30-day mortality rates were 2.1% for isolated AVR, 3.9% for AVR + CABG, 7.7% for AVR + other surgery and 6.2% for TAVI. In-hospital mortality has significantly improved for all groups. The 5-year survival rates were 82.6% for isolated AVR, 81.7% for AVR + CABG, 74.5% for AVR + other surgery and 46.1% for TAVI. The median PLOS after TAVI was similar to that of isolated AVR but shorter than that of the other AVR groups. CONCLUSIONS Since the introduction of TAVI, there has been an increase in both TAVI and AVR activity. TAVIs now represent over 10% of all aortic valve implants. There are distinct differences between procedural groups with respect to patient risk factors. Outcomes for all procedural groups have improved, but long-term TAVI results are required before its role in the treatment of aortic stenosis can be fully defined.

Use of intraaortic balloon pump in left ventricle rupture after mitral valve replacement.

Over 6 years of a single surgeon experience, 3 patients had left ventricle rupture following mitral valve replacement, despite preserving the posterior leaflet. The valve was re-replaced on bypass in all patients. Intraaortic balloon pump was inserted electively before coming off bypass. There were no intraoperative deaths, reexploration, or excessive bleeding. An intraaortic balloon pump is an ideal adjuvant to left ventricle repair for ruptured ventricle following mitral valve replacement on cardiopulmonary bypass.

Manubrium-limited sternotomy decreases blood loss after aortic valve replacement surgery

OBJECTIVES Minimally invasive surgical approaches for aortic valve replacement (AVR) are growing in popularity in an attempt to decrease morbidity from conventional surgery. We have adopted a technique that divides only the manubrium and spares the body of the sternum. We sought to determine whether patients benefit from this less-invasive approach. METHODS We retrospectively analysed our prospectively maintained database to review all isolated aortic valve replacements performed in an 18-month period from November 2011 to April 2013. RESULTS One hundred and ninety-one patients were identified, 98 underwent manubrium-limited sternotomy (Mini-AVR) and 93 had a conventional median sternotomy (AVR). The two groups were well matched for preoperative variables and risk (mean logistic EuroSCORE mini-AVR 7.15 vs AVR 6.55, P = 0.47). Mean cardiopulmonary bypass and aortic cross-clamp times were 10 and 6 min longer, respectively, in the mini-AVR group (mean values 88 vs 78 min, P = 0.00040, and 66 vs 60 min, P = 0.0078, respectively). Mini-AVR patients had significantly less postoperative blood loss, 332 vs 513 ml, P = 0.00021, and were less likely to require blood products (fresh-frozen plasma and platelets), 24 vs 36%, P = 0.042. Postoperative complications and length of stay were similar (discharge on or before Day 4; mini-AVR 15 vs AVR 8%, P = 0.17). Valve outcome (paravalvular leak mini-AVR 2 vs AVR 1%, P = 1.00) and survival (mini-AVR 99 vs AVR 97%, P = 0.36) were equal. CONCLUSIONS A manubrium-limited approach maintains outcomes achieved for aortic valve replacement by conventional sternotomy while significantly reducing postoperative blood loss and transfusion of blood products.

Acute Fibrin Deposition Causing Acute Failure of Two Tissue Pericardial Valves

We report the early failure of two tissue valves within hours of surgery due to the accumulation of cellular debris in two different institutions in the United Kingdom. The valves were both found at explant to be covered in a cellular material - possibly fibrin. From clinical experience and careful review of the literature we have found no other reports of such early valve failure due to the build up of material on the structure of the valve. This rare occurrence needs to be reported in the literature to forewarn clinicians of an early complication that may not be recognized yet.