Post-operative ventricular flow dynamics following atrioventricular valve surgical and device therapies : a review

Intra-ventricular flow dynamics has recently emerged as an important evaluation and diagnosis tool in different cardiovascular conditions. The formation of vortex pattern during the cardiac cycle has been suggested to play important epigenetic and energy-modulation roles in cardiac remodelling, adaptations and mal-adaptations. In this new perspective, flow alterations due to different cardiovascular procedures can affect the long-term outcome of those procedures. Especially, repairs and replacements performed on atrioventricular valves are likely to exert direct impact on intra-ventricular flow pattern. In this review, current consensus around the roles of vortex dynamics in cardiac function is discussed. An overview of physiological vortex patterns found in healthy left and right ventricles as well as post-operative ventricular flow phenomenon owing to different atrioventricular valvular procedures are reviewed, followed by the summary of different vortex identification schemes used to characterise intraventricular flow. This paper also emphasises on future research directions towards a comprehensive understanding of intra-cardiac flow and its clinical relevance. The knowledge could encourage more effective pre-operative planning and better outcomes for current clinical practices

Impact of different Asian ethnic groups on correlation between heparin dose, activated clotting time and complications in percutaneous coronary intervention

International Journal of Cardiology1303500-50

Ex vivo assessment of bicuspidization repair in treating severe functional tricuspid regurgitation : a stereo-scopic PIV study

There has been a resurgence of interest in the treatment of severe functional tricuspid regurgitation (FTR) due to the awareness of its poor outcomes and potential percutaneous therapies. Kay bicuspidization has been adapted in percutaneous therapies but its clinical outcome remains uncertain. The present study evaluates the efficacy of Kay repair in a novel ex vivo pulsatile system. Porcine tricuspid valve (TV) (n = 3) was extracted and incorporated into a patient-specific silicon right ventricle (RV) emulating severe FTR, on which Kay repair was subsequently performed. TV area metrics and RV hemodynamic assessment by means of stereo-scopic particle image velocimetry were quantified in both FTR and post-repair conditions. Bicuspidization led to significant increase in cardiac output although the overall increment due to this approach alone was generally small, possibly due to existence of residual TR and the large reduction in TV opening area. Kinetic energy and viscous loss levels were increased post-repair, especially during diastolic filling. Main vortex structures generally maintained post-procedural. However, there was enhanced swirling motion in larger RV domain. Although this might reduce mural-thrombus risk, the relatively more complex vortex phenomenon likely resulted in elevated viscous loss observed and may potentially impact long-term adaptation. The RV hemodynamic alteration after tricuspid repair could be used to predict the success of these future transcatheter solutions.Published versio

Differential MicroRNA Expression Profile in Myxomatous Mitral Valve Prolapse and Fibroelastic Deficiency Valves

10.3390/ijms17050753INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES17

Does pulmonary artery pulsatility index predict mortality in pulmonary arterial hypertension?

10.1002/ehf2.13450ESC HEART FAILURE853835-384

Rethinking COVID-19 'pneumonia' - is this primarily a vaso-occlusive disease, and can early anticoagulation save the ventilator famine?

10.1177/2045894020931702PULMONARY CIRCULATION10

Percutaneous pulmonary valve implantation as an alternative to repeat open-heart surgery for patients with pulmonary outflow obstruction: a reality in Singapore

10.11622/smedj.2018141SINGAPORE MEDICAL JOURNAL605260-26