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There is significant variation in practice with respect to the prescription and progression of upper limb exercises, within outpatient cardiac rehabilitation in Australia. Further research is warranted to establish evidence-based guidelines for the upper limb rehabilitation of patients following cardiac surgery via median sternotomy.

Intraoperative methylprednisolone administration does not reduce persistent incisional pain at 6 months in patients recovering from cardiac surgery.

Background - Endocardial-epicardial dissociation (EED) and focal breakthroughs in humans with atrial fibrillation (AF) have been recently demonstrated using activation mapping of short 10-second AF segments. In the current study we used simultaneous endo-epi phase mapping to characterise endo-epi activation patterns on long segments of human persistent AF (PeAF). Methods - Simultaneous intra-operative mapping of endo- and epicardial lateral RA wall was performed in patients with PeAF using two high-density grid catheters (16 electrodes, 3mm spacing). Filtered unipolar and bipolar electrograms (EGM's) of continuous 2-min AF recordings and electrodes locations were exported for phase analyses. We defined EED as phase difference of ≥20ms between paired endo-epi electrodes. Wavefronts (WF) were classified as rotations, single WF (SWF), focal waves or disorganised activity as per standard criteria. Endo-Epi WF patterns were simultaneously compared on dynamic phase maps. Complex fractionated EGM's were defined as bipolar EGM's with ≥5 directional changes occupying at least 70% of sample duration. Results - Fourteen patients with PeAF undergoing cardiac surgery were included. EED was seen in 50.3% of phase maps with significant temporal heterogeneity. Disorganised activity (Endo:41.3% vs Epi:46.8%, p=0.0194) and SWF (Endo:31.3% vs Epi:28.1%, p=0.129) were the dominant patterns. Transient rotations (Endo:22% vs Epi:19.2%, p=0.169; mean duration: 590±140ms) and non-sustained focal waves (Endo:1.2% vs Epi:1.6%, p=0.669) were also observed. Apparent transmural migration of rotational activations (n=6) from the epi- to the endocardium was seen in 2 patients. EGM fractionation was significantly higher in the epicardium than endocardium (61.2% vs 51.6%, p<0.0001). Conclusions - Simultaneous endo-epi phase mapping of prolonged human PeAF recordings shows significant EED marked temporal heterogeneity, discordant and transitioning WF patterns and complex fractionations. No sustained focal activity was observed. Such complex 3D-interactions provide insight into why endocardial mapping alone may not fully characterise the AF mechanism and why endocardial ablation may not be sufficient.

Surgical investigators should not use the K-M technique to predict cumulative survival or risk if there are two competing adverse events. They should use, instead, the technique of actual cumulative survival or incidence analysis.

Levosimendan is emerging as a novel cardioprotective inotrope. Levosimendan augments myocardial contractility by sensitising contractile myofilaments to calcium without increasing myosin adenosine triphosphatase activity or oxygen consumption. Levosimendan activates cellular adenosine triphosphate-dependent potassium channels, a mechanism which is postulated to protect cells from ischaemia in a manner similar to ischaemic preconditioning. Levosimendan may therefore protect the ischaemic myocardium during ischaemia-reperfusion as well as improve the contractile function of the heart. Adenosine triphosphate-dependent potassium channel activation by levosimendan may also be protective in other tissues, such as coronary vascular endothelium, kidney and brain. Clinical trials in patients with decompensated heart failure and myocardial ischaemia show levosimendan to improve haemodynamic performance and potentially improve survival. This paper reviews the known pharmacology of levosimendan, the clinical experience with the drug to date and the potential use of levosimendan as a cardioprotective agent during surgery.