SUMMARYA Patent Foramen Ovale (PFO) is detectable in 20-25% of the population. Some, but not all, case control studies have found an increased incidence of PFO in patients with cryptogenic stroke. Prospective cohort studies have failed to convincingly demonstrate a link between PFO and first stroke, and evidence linking PFO to recurrent stroke is far from compelling. The rate of recurrent stroke in medically treated patients is low, but the development of devices for PFO closure has lead to enthusiasm in some quarters to pursue a strategy of device closure. Nonrandomized studies have suggested a lower risk of recurrent events with device closure but the data are heterogeneous, and potentially prone to bias. Device implantation is associated with a risk of major adverse events of between 1.5% and 2.3%, and there is a significant rate of failure to close shunts. The results of randomized trials of device closure are keenly awaited. Migraine with aura has been linked with PFO. A recent metanalysis suggested an association, but the one prospective population study did not. The well-publicized and controversial MIST Trial is the only randomized trial of device closure in migraineurs yet published, and failed to demonstrate a convincing benefit from device closure. Other conditions such as platypnea-orthodeoxia syndrome and prevention of decompression sickness in divers, may justify device closure. Evidence for a role of PFO in the etiology of cryptogenic stroke and migraine is contradictory. It is possible that some patients might benefit from PFO closure but there is scant evidence of sufficient quality to justify routine PFO closure in either group. It is essential that ongoing randomized trials of device closure are completed. Prevalence and DetectionA patent foramen ovale (PFO) is a slit or tunnel like passage in the interatrial septum (IAS) formed by failure of postnatal fusion of the septum primum and septum secundum. Persistent PFO occurs in around 20-25% of the adult population, the exact frequency dependent on the method of detection. An autopsy based study suggested that the prevalence of PFO decreased with age implying either spontaneous closure or, intriguingly, a significant early death rate in those with PFOs [1]. However recent evidence from a large surgical series suggests that this is not the case and prevalence does not relate to age [2].Transthoracic echocardiography (TTE), transoesophageal echocardiography (TOE), and transcranial Doppler (TCD) can all be used to detect . TOE has traditionally been regarded as the gold standard but has some significant disadvantages. Whilst in some individuals a PFO is obvious on 2D echo or color flow on TOE, injection of bubble contrast is needed in many to clearly demonstrate a right to left shunt (see Figure 1). Patient sedation, positioning in the left decubitus position and the inability to perform a complete Valsalva may make it more difficult to visualize a shunt with bubbles on TOE than on TTE where the patient is semiupright and able to perform a good Vals...

Cardiac disease in patients with transfusion-dependent beta-thalassaemia major is well described. Cardiac manifestations may include left ventricular wall thickening and both systolic and diastolic dysfunctions. We describe a group of family members, including a pair of identical twins, each of whom suffered from thalassaemia major requiring multiple transfusions. Cardiac magnetic resonance demonstrated myocardial iron overload, and impairment of systolic function. Echocardiography confirmed both significant left ventricular systolic and diastolic impairment, along with features consistent with left ventricular non-compaction. This finding has not been noted in association with thalassaemia-related cardiac disease before. We then review the cardiac manifestations which occur in association with thalassaemia major.

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Background: In patients (pts) with sick sinus syndrome (SSS), right ventricular apical (RVA) pacing increased the risk of developing atrial fibrillation (AF). However, the mechanism of proarrhythmic effect of RVA pacing remains unclear. Methods: We performed detailed echocardiograhic examination with Tissue Doppler Imaging in 60 pts with SSS (mean age 73A9 years, 42 F) who implanted with DDD pacemakers during atrial and ventricular pacing with atrioventricular interval programmed at 120-150 mesc (ApVp mode) and AAI mode with (ApVs mode) at 70 bpm. Echo measurements were taken after 15 mins of pacing in each mode. The myocardial atrial contraction velocity was measured at annulus of right free wall (Ra), septal (Sa) and lateral free wall (La) respectively. Results: As expected, the AV interval was significantly shorter (118A25 vs.163A45 ms, P=0.002), and QRS duration was longer (146A33 vs.97A26 ms, P,0.001) during ApVp mode as compared with ApVs mode. Although there was no significant difference in left ventricular ejection fraction, left atrial (LA) ejection fraction (50A14 vs.55A14%, P=0.005), LA active emptying fraction (32A17 vs.37A16%, P=0.018) and LA filling fraction (43A13 vs. 48A13%, P=0.007) were all significant improved by 18%, 54% and 18%, respectively during ApVs mode as compared with ApVp mode. Furthermore, atrial myocardial contraction velocities among Ra (14.0A3.8 vs.15.2A4.6cm/s, P=0.026), Sa (7.8A2.6 vs. 8.8A2.8cm/s, P=0.001), and La (8.9A3.2 vs.9.7A2.7cm/s, P=0.020) were also significantly increased during ApVs mode by 12%, 19% and 21%, respectively as compared with ApVp mode (Figure). Conclusions: In pts with SSS, avoidance of RVA pacing during ApVs mode improves LA haemodynamic and mechanical function, which might contribute to a lower risk of development of AF after pacemaker implantation. P773Qualitative and quantitative assessment of 3 novel post-processing methods for enhancing echocardiographic images. Echocardiography, while a prevalent tool for assessing cardiac morphology and function, suffers from a range of artefacts that reduce its diagnostic value. This work qualitatively and quantitatively evaluates 3 novel post-processing methods for enhancing echocardiographic images. Data enhancement is achieved by utilising multiple partially decorrelated instances of a cardiac cycle acquired through a single acoustic window. Such information has until now been largely disregarded during data post-processing. Moreover, unlike past approaches, data enhancement is achieved without filtering out information based on static or adaptive selection criteria. Qualitative assessment using 32 clinical datasets demonstrated (i) suppression of cavity noise, (ii) increase in tissue/cavity contrast, and (iii) visual enhancement of tissue structures previously masked-out by various artefacts (Figure 1). The effect of each post-processing method on the diagnostic value of cardiac ultrasound data was quantitatively assessed by examining the repeatability coefficient variations (via Bland-Altman plots) in clini...