Initial experience with the convergent procedure for longstanding persistent atrial fibrillation: A 5 year dataset.

In patients with longstanding persistent atrial fibrillation (AF), outcomes from catheter ablation remain suboptimal. The convergent procedure combines minimally invasive surgical ablation with subsequent catheter ablation, and may contribute towards maintenance of sinus rhythm in this patient group. We performed the convergent procedure on 43 patients with longstanding persistent AF from 2013-2018. Patients underwent clinical review at 3, 6, and 12 months and thereafter as necessitated by their symptoms. Our dataset describes patients' baseline characteristics and rhythm control protocols, as well as outcomes including arrhythmia recurrence, the need for antiarrhythmic drugs, requirement for repeat rhythm control procedures, and complications. These data provide a real world insight into the risks and benefits of the convergent procedure in patients with longstanding persistent AF.

The convergent procedure versus catheter ablation alone in longstanding persistent atrial fibrillation: A single centre, propensity-matched cohort study.

BACKGROUND: Maintenance of sinus rhythm is challenging in patients with longstanding persistent atrial fibrillation (PeAF). Minimally invasive surgical AF ablation may improve outcomes when combined with catheter ablation (the 'convergent' procedure). This study evaluates the safety and efficacy of the convergent procedure versus catheter ablation alone in longstanding PeAF. METHODS: 43 consecutive patients with longstanding PeAF underwent subxiphoid endoscopic ablation of the posterior left atrium followed by catheter ablation from 2013 to 2018. The primary outcome was AF-free survival at 12 months; secondary outcomes included change in EHRA class, echocardiographic data, procedural complications, freedom from anti-arrhythmic drugs (AADs), and long term arrhythmia-free survival. Outcomes were compared with a matched group of 43 patients who underwent catheter ablation alone. Both groups underwent multiple catheter ablations as required. Baseline characteristics were similar between groups. RESULTS: After 12 months, the convergent procedure was associated with increased AF-free survival on AADs (60.5% versus 25.6%, p = .002) and off AADs (37.2% versus 13.9%, p = .025), versus catheter ablation. Allowing for multiple procedures, after 30.5 ±â€¯13.3 months' follow-up the convergent procedure was associated with increased arrhythmia-free survival on AADs (58.1% versus 30.2%, p = .016) and off AADs (32.5% versus 11.6%, p = .036) versus catheter ablation. There were more complications in the convergent procedure group (11.6% versus 2.3%, p = .2). Multivariate analysis identified only the convergent procedure (OR 3.06 (1.23-7.6), p = .017) as predictive of arrhythmia-free survival long term. CONCLUSIONS: In longstanding PeAF, the convergent procedure is associated with improved arrhythmia-free survival versus catheter ablation alone. Complication rates are significant but have been shown to depreciate with experience.

The effect of cyclosporin-A on peri-operative myocardial injury in adult patients undergoing coronary artery bypass graft surgery: a randomised controlled clinical trial.

OBJECTIVE: Cyclosporin-A (CsA) has been reported to reduce myocardial infarct size in both the experimental and clinical settings. This protective effect is dependent on its ability to prevent the opening of the mitochondrial permeability transition pore, a critical determinant of cell death in the setting of acute ischaemia-reperfusion injury. Whether CsA can reduce the extent of peri-operative myocardial injury (PMI) in patients undergoing coronary artery bypass graft (CABG) surgery is unknown, and is investigated in this randomised controlled clinical trial. METHODS: 78 adult patients undergoing elective CABG surgery were randomised to receive either an intravenous bolus of CsA (2.5 mg/kg) or placebo administered after induction of anaesthesia and prior to sternotomy. PMI was assessed by measuring serum cardiac enzymes, troponin T (cTnT) and CK-MB at 0, 6, 12, 24, 48 and 72 h after surgery. RESULTS: There was no significant difference in mean peak cTnT levels between control (n=43) and CsA treatment (n=40) patients (0.56±0.06 ng/mL with control vs 0.35±0.05 ng/mL with CsA; p=0.07). However, in higher-risk patients with longer cardiopulmonary bypass times, there was a significant reduction in PMI with CsA therapy (p=0.049), with a reduced postoperative cTnT rise by 0.03 ng/mL for every 10 min, when compared with control. CONCLUSIONS: In patients with longer cardiopulmonary bypass times, a single intravenous bolus of CsA administered prior to CABG surgery reduced the extent of PMI.

Remote ischaemic preconditioning reduces myocardial injury in patients undergoing cardiac surgery with cold-blood cardioplegia: a randomised controlled trial.

BACKGROUND: Remote ischaemic preconditioning (RIPC) induced by brief ischaemia and reperfusion of the arm reduces myocardial injury in coronary artery bypass (CABG) surgery patients receiving predominantly cross-clamp fibrillation for myocardial protection. However, cold-blood cardioplegia is the more commonly used method world wide. OBJECTIVE: To assess whether RIPC is cardioprotective in CABG patients receiving cold-blood cardioplegia. DESIGN: Single-centre, single-blinded, randomised controlled trial. SETTING: Tertiary referral hospital in London. PATIENTS: Adults patients (18-80 years) undergoing elective CABG surgery with or without concomitant aortic valve surgery with cold-blood cardioplegia. Patients with diabetes, renal failure (serum creatinine >130 mmol/l), hepatic or pulmonary disease, unstable angina or myocardial infarction within the past 4 weeks were excluded. INTERVENTIONS: Patients were randomised to receive either RIPC (n = 23) or control (n = 22) after anaesthesia. RIPC comprised three 5 min cycles of right forearm ischaemia, induced by inflating a blood pressure cuff on the upper arm to 200 mm Hg, with an intervening 5 min reperfusion. The control group had a deflated cuff placed on the upper arm for 30 min. MAIN OUTCOME MEASURES: Serum troponin T was measured preoperatively and at 6, 12, 24, 48 and 72 h after surgery and the area under the curve (AUC at 72 h) calculated. RESULTS: RIPC reduced absolute serum troponin T release by 42.4% (mean (SD) AUC at 72 h: 31.53 (24.04) microg/l.72 h in controls vs 18.16 (6.67) microg/l.72 h in RIPC; 95% CI 2.4 to 24.3; p = 0.019). CONCLUSIONS: Remote ischaemic preconditioning induced by brief ischaemia and reperfusion of the arm reduces myocardial injury in CABG surgery patients undergoing cold-blood cardioplegia, making this non-invasive cardioprotective technique widely applicable clinically. TRIAL REGISTRATION NUMBER: NCT00397163.

Erythropoietin protects the human myocardium against hypoxia/reoxygenation injury via phosphatidylinositol-3 kinase and ERK1/2 activation.

BACKGROUND AND PURPOSES: Erythropoietin (EPO) has been shown to protect against myocardial infarction in animal studies by activating phosphatidylinositol-3 kinase (PI3K)/Akt and ERK1/2. However these pro-survival pathways are impaired in the diabetic heart. We investigated the ability of EPO to protect human atrial trabeculae from non-diabetic and diabetic patients undergoing coronary artery bypass surgery, against hypoxia-reoxygenation injury. EXPERIMENTAL APPROACH: Human atrial trabeculae were exposed to 90min hypoxia and 120min reoxygenation. EPO was administered throughout reoxygenation. The developed force of contraction, calculated as a percentage of baseline force of contraction, was continuously monitored. The involvement of PI3K and ERK1/2 and the levels of activated caspase 3(AC3) were assessed. KEY RESULTS: EPO improved the force of contraction in tissue from non-diabetic patients (46.7+/-1.7% vs. 30.2+/-2.2% in control, p<0.001). These beneficial effects were prevented by the PI3K inhibitor, LY294002 and the ERK1/2 inhibitor, U0126. EPO also significantly improved the force of contraction in the diabetic tissue, although to a lesser degree. The levels of activated caspase 3 were significantly reduced in EPO treated trabeculae from both non-diabetic and diabetic patients, relative to their respective untreated controls. CONCLUSIONS AND IMPLICATIONS: EPO administered at reoxygenation protected human myocardial muscle by activating PI3K and ERK1/2 and reducing the level of activated caspase 3. This cardioprotection was also observed in the diabetic group. This data supports the potential of EPO being used as a novel cardioprotective strategy either alone or as an adjunct in the clinical setting alongside existing reperfusion therapies.

Floating thrombus in the aorta.

A review of the literature shows that there are few reported cases of embolism or thrombus in a nonaneurysmal, effectively normal aorta with no other underlying reason for thrombus formation in the aorta. We report a case of a large, floating thrombus in the descending aorta lumen and discuss surgical and management options.

Use of support stockings after cardiac surgery.

Saphenous leg veins are commonly used in coronary artery bypass grafting. Removal of the vein may cause oedema, erythema and tenderness in the leg. External support stockings are often used routinely to ease these common symptoms and prevent deep vein thrombosis.

A porcine model of prolonged closed chest venovenous extracorporeal membrane oxygenation.

The sheep has been the standard laboratory animal for extracorporeal membrane oxygenation (ECMO) research for many years and has proven to be an invaluable and reliable model. However the coagulation system of the sheep is significantly different from humans. These differences make it difficult to investigate the coagulative and inflammatory response to ECMO in sheep. The pig has a very similar coagulation system to humans and therefore makes a more appropriate model. We describe a porcine model of prolonged (48 hours) closed chest venovenous (VV) ECMO that we developed to investigate the inflammatory and coagulative response to different ECMO tubing materials. This model could be used to investigate any aspect of venovenous ECMO.

Signal averaged P wave compared with standard electrocardiography or echocardiography for prediction of atrial fibrillation after coronary bypass grafting.

OBJECTIVE: To define the clinical value of the signal averaged P wave (SAPW) and to compare it with the standard electrocardiogram (ECG), echocardiogram, and clinical assessment for the prediction of atrial fibrillation after coronary bypass grafting (CABG). DESIGN: Prospective validation cohort study. SETTING: Regional cardiothoracic centre. PATIENTS: 201 unselected patients undergoing first elective CABG were recruited over six months. Patients requiring concomitant valve surgery were excluded. MAIN OUTCOME MEASURES: Age, sex, cardiothoracic ratio, and cardioactive drugs were noted. P wave specific SAPW recordings, ECG, and M mode echocardiograms from which left atrial diameter was measured were performed within 24 hours of surgery. Filtered P wave duration (SAPWD), spatial velocity, and energy were calculated from the SAPW. From the ECG, lead II P wave duration, P terminal force in lead V1, total P wave duration, and isoelectric interval were measured. Patients had Holter monitoring for 48 hours postoperatively and daily ECGs until discharge. RESULTS: Two patients died (1%) and 10 were unsuitable for analysis (5%). Of the remaining 189, 51 (27%) had atrial fibrillation (AF) lasting > 1 hour at a mean of 2 (0.5 to 7) days after CABG. Of the variables examined, only SAPWD (AF group 148 (SD 12), v 142 (14) ms, P = 0.008) and male sex (AF group 96%, v 78%, P < 0.01) were significantly different. A prospectively defined SAPWD of > 141 ms predicted atrial fibrillation with positive and negative predictive accuracies of 34% and 83%. Logistic regression analysis identified both male sex and SAPWD as significant independent predictors of postoperative atrial fibrillation. CONCLUSIONS: Signal averaged P wave duration was a better predictor of atrial fibrillation after coronary bypass grafting than standard electrocardiographic or echocardiographic criteria. The predictive value of this test is such that it is likely to be useful in the design of prospective trials of prophylactic antiarrhythmic treatment but is of limited use using current techniques in the clinical management of individual patients.

Unusual presentation of an atrial septal aneurysm with left atrial myxoma: a case report.

A 68-year-old man with coronary artery disease and mitral regurgitation was referred for surgery. Intraoperative transoesophageal echocardiogram revealed mild mitral regurgitation, and an aneurysm of the atrial septum deviating to the right atrial side with mass in the left atrium. During operation the aneurysm of the atrial septum was excised with a small sessile myxoma from base of the atrial septum (2.5 cm X 2 cm X 1.5 cm).

Role of atrial ischaemia in development of atrial fibrillation following coronary artery bypass surgery.

OBJECTIVE: Atrial fibrillation (AF) is a common complication after coronary artery bypass grafting (CABG) operations, occurring in 5 to 40% of cases. A number of studies have implicated atrial ischaemia in the genesis of this arrhythmia. The aim of this study was to examine the relationship between atrial coronary anatomy and the incidence of post operative atrial fibrillation. METHOD: To investigate a possible anatomical explanation to the onset of AF after CABG, 25 patients with documented AF after CABG were matched and compared to 25 patients which remained in sinus rhythm (SR). All coronary angiograms were reported blindly by a cardiac radiologist with reference to the blood supply of the sino-atrial (SA) node and atrio-ventricular (AV) node before and after surgery. RESULTS: Univariate analysis of risk factors did not identify any significant difference (Fisher exact test, P > 0.05) between the two groups in age, gender, left ventricular function, ischaemic time, number of vessels diseased or grafted, renal dysfunction and withdrawal of beta-blockade. However, significant disease in the SA nodal artery was present in 2 patients of the SR group when compared to 9 in the AF group. Significant disease of AV nodal artery was present in only 4 patients of the SR group when compared to 18 in the AF group. Comparison between the two groups showed a significantly increased incidence of SA or AV nodal artery disease in the AF group, (SA: P = 0.018, AV: P = 0.0001). Mean hospital stay was 8.1 days for the SR group and 9.1 days in the AF group (P = 0.175). CONCLUSION: Obstructive disease in the SA nodal and AV nodal arteries is more common in patients developing atrial fibrillation following coronary artery bypass surgery than those who remain in sinus rhythm. If the incidence of AF could be predicted by the anatomical distribution of arterial disease then targeting prophylaxis to this group may be possible.