Left ventricular assist device (LVAD)-related infections are a leading cause of morbidity and mor... more Left ventricular assist device (LVAD)-related infections are a leading cause of morbidity and mortality, with fungal infections being particularly difficult to manage. We report a case of an immunocompetent 39-year-old male with an LVAD and an implantable cardiac device (ICD) who developed fatal Scedosporium apiospermum fungaemia. To the best of our knowledge, this is the first reported case of LVAD-related S. apiospermum fungaemia.
Background: Restrictive mitral annuloplasty is the mainstay of surgical correction of chronic isc... more Background: Restrictive mitral annuloplasty is the mainstay of surgical correction of chronic ischaemic mitral regurgitation (CIMR). Long-term data on the various types of annuloplasty rings is limited. The aim of this study was to investigate the clinical and echocardiographic outcomes of restrictive mitral annuloplasty in patients with CIMR, comparing the use of flexible versus semi-rigid annuloplasty rings. Methods: A retrospective review was conducted for 133 patients with CIMR who underwent restrictive mitral annuloplasty at our institution between 1999 and 2015. Patient demographics and postoperative outcomes were analyzed. Results: Mean age was 61.9±9.2 years and 103 patients (77.4%) were male. All patients underwent coronary artery bypass grafting, with a mean of 3.3±0.8 grafts. Flexible rings was implanted in 39 patients (29.3%, group F) and semi-rigid rings in 94 (70.7%, group R). Preoperative New York Heart Association class was III/IV in 104 patients (78.2%). Mean preoperative left ventricular ejection fraction was 28.8%±10.2%. Preoperative mitral regurgitation was moderate in 51 patients (38.3%) and severe in 82 (61.7%). In-hospital mortality occurred in 11 patients (8.3%). Overall survival at 1, 5 and 10 years were, respectively, 86.4%, 69.7% and 45.9%. At 10 years, overall survival (group F 53.1%, group R 40.0%, P=0.330) and freedom from moderate to severe MR (group F 53.1%, group R 53.8%, P=0.725) did not differ significantly. Freedom from hospitalization for heart failure was 59.3%. Left ventricular reverse remodelling, defined as a reduction of left ventricular end-systolic volume index >15%, occurred more commonly in Group R (51.1%) compared to Group F (23.1%), P=0.003. Conclusions: Restrictive mitral annuloplasty was associated with an operative mortality of 8.3%. Heart failure symptoms and significant MR recur in approximately 40% of patients after 10 years. Survival remained suboptimal and was not influenced by the type of annuloplasty ring.
Background: ACRE pathway was implemented at TUH in October 2018. The aim of this study was to ana... more Background: ACRE pathway was implemented at TUH in October 2018. The aim of this study was to analyse its impact on exercise stress test (EST) referrals in TUH. Methods: Retrospective analysis of 558 emergency department (ED) chest pain presentations was done over six months, including the appropriateness of risk stratification and referrals for EST, waiting time for EST, and representations to ED whilst awaiting EST. Results: Of the 558 ED presentations, 76.7% had risk category documented appropriately. Only 48.4% of the intermediate risk patients were referred for an outpatient EST from ED. Of the 132 EST referrals, the median waiting period was 4 weeks, with 51 (39%) completed within 2 weeks. There were 91 representations to ED while waiting for EST, and 48 (54%) of those patients were discharged from ED. Conclusion: As expected, implementing change to accelerated diagnostic protocol significantly increased the EST referrals.
Background: Vascular Endothelial Dysfunction (VED) plays a fundamental role in the pathophysiolog... more Background: Vascular Endothelial Dysfunction (VED) plays a fundamental role in the pathophysiology of a number of cardiovascular disease states, including atherosclerosis, acute coronary syndromes/myocardial infarction, hypertension and heart failure. These cardiovascular disease states have also been linked with physical frailty and sarcopenia. Elevated inflammatory status and oxidative stress have been associated with both cardiovascular diseases states and physical frailty, although the exact pathophysiological mechanisms linking the two conditions remain largely unknown. We hypothesize that inflammation-related pathological changes in the vascular endothelium may result in VED, which in turn result in cardiovascular disease states and thus frailty and sarcopenia. Aim: To delineate a possible association between VED and frailty/sarcopenia. Method: A systematic literature review was performed according to PRISMA principles to identify relevant published studies between January 2000 to August 2019. Only original human or animal research studies in English language were included. Results: Twenty-five studies were eligible for inclusion. VED is independently associated with increased frailty phenotypes and measures of sarcopenia. Several markers of VED, including elevated levels of asymmetric dimethylarginine, homocysteine, abnormal ankle brachial index, pulse wave velocity, pulse pressure and lower levels of flowmediated dilatation, peripheral blood flow, endothelial progenitor cells and s-klotho protein have been associated with higher levels of physical frailty and sarcopenia measurements with some studies demonstrating the role of inflammation in modulating this association. Conclusions: VED may potentially be an early marker of sarcopenia and frailty, although the exact mechanism(s) underlying the association between VED and sarcopeniarelated physical frailty have yet to be delineated.
Interactive Cardiovascular and Thoracic Surgery, Oct 25, 2019
A best evidence topic in cardiac surgery was written according to a structured protocol. The ques... more A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Does concurrent use of intra-aortic balloon pump (IABP) improve survival in patients with cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation (VA-ECMO)?'. Altogether 472 papers were found using the reported search, of which 3 level 2 systematic reviews represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The reported comparative outcomes were mortality, weaning off extracorporeal membrane oxygenation (ECMO), vascular complications and non-vascular complications. One systematic review demonstrated significantly lower in-hospital mortality with concurrent use of IABP and VA-ECMO, while the other 2 studies showed no difference in mortality. One paper reported on the weaning success from ECMO and demonstrated significantly higher weaning success with concurrent IABP usage. Another paper reported on the complications and showed no differences in vascular and non-vascular complications. We conclude that there was no significant improvement in survival with the concurrent use of IABP and VA-ECMO for a cardiogenic shock as compared to the use of VA-ECMO alone. However, the concurrent use of IABP with VA-ECMO improved weaning success from VA-ECMO. The incidence of vascular and non-vascular complications was similar with or without IABP usage.
A telecare project has been established which allows outpatients to monitor their own health with... more A telecare project has been established which allows outpatients to monitor their own health with the assistance of SingHealth clinicians. Communication takes place through a Web portal and/or by mobile phone text messaging (SMS). The pilot service has been used by local and overseas patients with chronic diseases such as heart failure, hypertension, renal failure, diabetes and suspected occupational asthma. Through the telecare system, which was developed in-house, clinicians can configure a personalized monitoring plan (vital signs and symptoms) for each patient and follow up with interactive charts. The patient's health data are transmitted to the telecare system by the patient or care-giver, through a Web portal or by SMS messages. If a patient's health indicators fall outside predefined thresholds, clinicians can be alerted by SMS. Patients and clinicians can also communicate through the portal. Apart from chronic disease management, the system has also been used to rep...
The Malaysian Journal of Medical Science, Jun 27, 2023
Background: Intracerebral haemorrhage (ICH) can be devastating, particularly if haematoma expansi... more Background: Intracerebral haemorrhage (ICH) can be devastating, particularly if haematoma expansion occurs. The efficacy of tranexamic acid (TXA), an anti-fibrinolytic agent, in reducing haematoma expansion is now being studied worldwide. However, the optimal dosage of TXA has yet to be determined. This study was designed to further establish the potential of different doses of TXA. Methods: A double-blinded, randomised, placebo-controlled study was carried out among adults with non-traumatic ICH. Eligible study subjects were randomly assigned to receive placebo, 2-g TXA treatment or 3-g TXA treatment. Haematoma volumes before and after intervention were measured using the planimetric method. Results: A total of 60 subjects with 20 subjects in each treatment group were recruited for this study. Among the 60 subjects, the majority were male (n = 36, 60%), had known cases of hypertension (n = 43, 71.7%) and presented with full Glasgow coma scale (GCS) (n = 41, 68.3%). The results showed that there was no statistically significant difference (P = 0.315) in the mean changes of haematoma volume when compared with three study groups using ANCOVA, although the 3-g TXA group was the only group that showed haematoma volume reduction (mean reduction of 0.2 cm 3) instead of expansion as in placebo (mean expansion 1.8 cm 3) and 2-g TXA (mean expansion 0.3 cm 3) groups. Good recovery was observed in all study groups, with only three subjects being moderately disabled. No adverse effects were reported in any of the study groups. Conclusion: To the best of our knowledge, this is the first clinical study using 3 g of TXA in the management of non-traumatic ICH. From our study, 3 g of TXA may potentially be helpful in reducing haematoma volume. Nonetheless, a larger-scale randomised controlled trial should be carried out to further establish the role of 3 g of TXA in non-traumatic ICH.
Saksenaea vasiformis complex is an emerging cause of mucormycosis. We report a case of an immunoc... more Saksenaea vasiformis complex is an emerging cause of mucormycosis. We report a case of an immunocompetent patient presenting with a nonresolving lung mass who developed multiple skin nodules. Skin biopsy yielded Saksenaea vasiformis complex. This showcases an uncommon occurrence of disseminated Saksenaea infection without cutaneous inoculation that improved with posaconazole.
The Journal of Heart and Lung Transplantation, 2021
Purpose The incidence of driveline fractures among patients on HeartMate II Left Ventricular Assi... more Purpose The incidence of driveline fractures among patients on HeartMate II Left Ventricular Assist Device (LVAD) support is reviewed Methods This is a single-center, retrospective review of all the patients on HeartMate II LVAD support who presented with driveline fractures. Patients’ presentation, interventions, and outcome following corrective treatment were examined. Results Between May 2009 and October 2018, 60 HeartMate II LVAD were implanted. Over a cumulative support period of 81 patient-years (maximum, 8.5 years), 15 patients (25%) had driveline fractures (age 14-70, 2 female), 5 of them were destination therapy (> 65 years old). Mean duration from the time of implant to driveline fractures was 44.5 ± 15.5 months. 12 patients had significant weight gain following LVAD implant, ranging from 5.2 to 32.3kg (median 17.4kg). While tethered on to power module, 8 patients (53.3%) encountered intermittent pump stoppage, 5 (33.3%) had transient low pump speed, 1 (6.7%) had recurrent driveline fault and 1 more (6.7%) presented with hemoserous discharge leaking from broken insulation in the external driveline with multiple recurrent low voltage advisory. Ungrounded cable was issued to 13 patients as a temporary measure with mean duration of its usage of 259 days (range 26-980 days), before corrective treatment. There were 2 patients with ongoing use of the ungrounded cable (mean 1 year). 8 patients (53.3%) underwent pump replacement, 2 with significant external driveline fractures successfully underwent external driveline replacement and 1 underwent heart transplant. Of the 9 pumps returned for analysis, 7 (78%) were found to have damaged internalized part of the driveline while 2 (22%) had circumferential fractures at the edge of the pump housing extending across the diameter of the bend relief. There were 3 mortality (20%), 1 due to recurrent pump pocket infection and pump thrombosis following the initial pump replacement for driveline fractures, 1 died of subdural haemorrhage before elective pump exchange and 1 died 3 weeks after pump stoppage. Conclusion The incidence of HeartMate II internal driveline fractures seemed to be higher in our Asian experience as opposed to what have been reported in literature. An ungrounded cable served as a temporary measure for short to shield and a timely pump exchange maybe lifesaving when driveline damage progressed into phase to phase.
The Journal of Heart and Lung Transplantation, 2019
Purpose: Very little is known about frailty in patients with a left ventricular assist device (LV... more Purpose: Very little is known about frailty in patients with a left ventricular assist device (LVAD) in general, and about reversibility of different measures of frailty post LVAD in particularly. The purpose of the study was to determine which measures of frailty improve post LVAD implantation. Methods: This was an observational, longitudinal (3 month) cohort study of 25 patients with advanced heart failure who underwent LVAD implantation between January 2015 and May 2016. Demographic and clinical data were retrieved from hospital medical records. The six minute walk test (6MWT) was conducted by physical therapist and hand grip strength was assessed by a nurse practitioner using a hand dynamometer. Paired t-test was used to determine differences between pre and post 6MWT, handgrip strength and serum albumin levels. Demographic and clinical characteristics were reported using frequencies, percentages for categorical variables and mean § standard deviation for continuous variables. Results: A majority of the patients were male (88%) and over 40% of the patients in the study were under the age of 60. The primary etiology of heart failure for his population was ischemic cardiomyopathy (60%). Complete data were collected on 23 patients. One patient died within 3 months of LVAD implant and one patient was wheelchair bound post LVAD implant. The mean pre-operative albumin level was 2.7 § .4 mg/dL with only 4% of patients having an albumin levels > 3.5 mg/dl. The albumin became normal after surgery (see Table). Only 8% of patients walked 300 feet or more in 6 minutes pre-implant. In contrast 53% were able to walk more than 300 feet at 3 months post-implant. There was no difference in hand grip strength. Conclusion: Albumin levels and 6MWT significantly improved 3 months post LVAD implant, while hand grip strength noted no improvement. Short 6MWT distance and low albumin should not preclude LVAD implant because these measures of frailty are reversible and are likely to improve shortly after surgery. Pre implant and Post implant Frailty Measures Frailty Measure Pre I mplant 3 Months Post Implant p value Hand grip strength 22.8 § 10.7 24.7 § 11.1 .06 Six minute walk (feet) 186 § 83.2 275 § 121.1 <.001 Albumin (mg/dl) 2.7 § .4 3.5 § .4 <.001
The Journal of Heart and Lung Transplantation, 2019
baloon pump preoperatif period. TAPSE was 13.4 §3.2 (7-20) mm, right ventricle FAC was 25 % § 7 (... more baloon pump preoperatif period. TAPSE was 13.4 §3.2 (7-20) mm, right ventricle FAC was 25 % § 7 (10-40). Mean INTERMACS was 2,8 §0,7 (1-4). The average cardiopulmonary bypass durations was 86,5,2 +/-29,7 min (range: 12-141). Peroperative red blood cell transfusion 1.6 § 1.4 (0-5) Unite, early right ventricular failure was 10.1%, mean mechanical ventilation time 2.1 § 2,5 8 1-15 days, intensive care unit length of stay was 7,3 §4,2 (1-16) days. At 443,7 days mean follow up time 82,5% survival was observed. The most common adverse event on device was driveline infection (18,3%). Gastrointestinal bleeding was 2%, hemorrhagic cerebrovascular event was 8%, pump trombosis 10,2%, late right ventricle failure 5%, hemorrhagic cerebrovascular event was 8%. Eleven patients (22,4%) were transplanted. Conclusion: Minimally invasive implantation of left ventricular assist devices both of two pump HeartWar (HVAD) and Heartmate 3 is safely feasible. After a very good initial experience with this technique it has become the method of choice in our department.
The Journal of Heart and Lung Transplantation, 2016
appears to be primarily a result of reduced serum albumin in this population (mean albumin 3.0 ± ... more appears to be primarily a result of reduced serum albumin in this population (mean albumin 3.0 ± 0.47 g/dL). It appears that low albumin levels and labile fluid status may render the NRI an ineffective means of assessing post-operative outcomes in AHF patients undergoing LVAD.
The Journal of Heart and Lung Transplantation, 2017
and received antibiotics, of which 61 (16%) were readmitted for DLIs and 27 (7%) required surgica... more and received antibiotics, of which 61 (16%) were readmitted for DLIs and 27 (7%) required surgical intervention. The most common pathogens in the surgery group were Pseudomonas Aeruginosa (26%), Methicillin-resistant Staphylococcus aureus (22%) and Methicillin-sensitive Staphylococcus aureus (19%). No individual surgical technique achieved higher rates of healing compared to others. The NPVD group included 90 patients with a follow-up of nearly 12 months. Fifteen patients (17%) were treated for DLIs, of which 7 (7%) required surgical intervention. There was a trend towards reduced total DLIs in the NPVD group (p< .09). Conclusion: DLIs continue to be a challenging and morbid complication, affecting nearly 25% of our patients. Although there was no significant difference in the healing rates between various surgical techniques, it does appear that the application of NPVD at the time of implantation might reduce the incidence of DLIs. Long-term follow-up and increased study size is needed to more fully define the efficacy of this intervention.
The Journal of Heart and Lung Transplantation, 2017
Increasingly Extracorporeal Membrane Oxygenation (ECMO) is being used as a bridge to decision for... more Increasingly Extracorporeal Membrane Oxygenation (ECMO) is being used as a bridge to decision for recovery, transplantation or to a durable left ventricular assist device (LVAD) for patients presenting with cardiogenic shock. We report our outcomes in INTERMACS I patients receiving a durable LVAD after bridging with ECMO. Methods: A retrospective review of 20 consecutive INTERMACS profile I patients who were bridged from ECMO support to continuous-flow LVAD between May 2009 and September 2016 in Singapore was performed in order to evaluate our outcomes based on our management protocol. Results: 16 were males. The aetiologies include acute coronary syndrome in 12 (60%), dilated cardiomyopathy in 4 (23%), myocarditis in 3 (15%) and ischemic cardiomyopathy in 1 (5%). Mean age at the time of LVAD implant was 40 (± 14) years old. The total length of LVAD support was 33 patient months. Twelve patients received HeartMate II LVAD and two received HeartMate III LVAD. Six received HeartWare LVAD. Majority (18, 90%) were BTT while two were DT (10%). Median duration of ECMO support was 10 days (range 1-23). Mean length of hospital stay following LVAD implant was 50 days (range 15-99). There was is no in-hospital mortality. Kaplan Meier survival at 1-year was 100% and 91.7% at 3-years. Following LVAD implantation, four (20%) received cardiac transplant and one (5%) had LVAD explant following myocardial recovery. Conclusion: Our zero peri-operative mortality in this high risk group suggests that our management protocol is valid. The 3-years survival too appears to be favourable compared to INTERMACS registry data.
Discussing the most challenging clinical cases / New invasive therapies and devices: reality or s... more Discussing the most challenging clinical cases / New invasive therapies and devices: reality or science fiction? 1131 3498 Alcohol septal ablation as a treatment of left ventricular outflow tract obstruction after mitral valve repair
European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery, 2015
OBJECTIVES To review our experience of surgical management of infective endocarditis (IE) over a ... more OBJECTIVES To review our experience of surgical management of infective endocarditis (IE) over a 13-year period and analyse the outcomes and associated prognostic factors. METHODS A retrospective review was conducted for 191 consecutive patients who underwent surgery for native and prosthetic valve endocarditis (PVE) between January 2000 and December 2012. Surgical outcomes were reviewed to include survival and postoperative complications. Follow-up was complete for 172 of 179 patients (96.1%) surviving to hospital discharge, with a mean follow-up of 6.6 ± 3.7 years. RESULTS Mean age was 47.4 ± 14.9 years with 113 (63.9%) males. Native valve endocarditis was present in 177 patients (92.7%). Sixty-three patients (33.0%) presented with embolic complications. The brain was the most common site of embolism, involving 25 patients (13.1%). Streptococcus viridans was the most common infective organism, isolated in 68 patients (35.7%), followed by Staphylococcus aureus in 30 patients (15.7%...
Limited data exists on patients receiving therapeutic hypothermia during extracorporeal life supp... more Limited data exists on patients receiving therapeutic hypothermia during extracorporeal life support (ECLS). We investigated outcomes and prognostic factors in these patients. A retrospective review was conducted for 225 consecutive adult patients treated with ECLS between July 2003 and January 2016. Extracorporeal life support was initiated for refractory cardiac arrest (>10 mins) in 79 patients (35.1%). Patient demographics, ECLS-related complications, in-hospital mortality and neurological outcomes were analysed. The mean age was 49.9±12.4 years. Sixty-two patients (78.5%) were male. The mean duration of CPR and ECLS were respectively, 32.0±23.3 mins and 5.4±4.0 days. Therapeutic hypothermia (34(o)C) was maintained for 24hours in 14 patients (17.7%). Thirty-five patients (44.3%) were weaned off ECLS. Twenty-one patients (26.6%) survived to hospital discharge with 16 (20.3%) recovering good neurological function. Compared to ECLS at normothermia, neurologically favourable survi...
Introduction: In November 2016, surgical antibiotic prophylaxis (SAP) guidelines for cardiothorac... more Introduction: In November 2016, surgical antibiotic prophylaxis (SAP) guidelines for cardiothoracic surgeries at the authors’ centre were updated. SAP was reduced from 48 to 24 hours, and dual cover with vancomycin and cefazolin instead of vancomycin monotherapy was recommended for patients colonised with methicillin-resistant Staphylococcus aureus. This study was conducted to review compliance to the updated guidelines, and compare the incidence of surgical site infections (SSI). Methods: A list of patients undergoing sternotomy in National Heart Centre, Singapore, from March 2016 to February 2019 was extracted from the hospital’s electronic database; every fourth patient was included in the analysis. The patients were divided into three groups: Group 1 (before guideline revision, March–October 2016), Group 2 (post-guideline implementation, July 2017–May 2018), and Group 3 (July 2018–February 2019). Compliance to guidelines, incidence, and epidemiology of SSIs within 90 days of sur...
Left ventricular assist device (LVAD)-related infections are a leading cause of morbidity and mor... more Left ventricular assist device (LVAD)-related infections are a leading cause of morbidity and mortality, with fungal infections being particularly difficult to manage. We report a case of an immunocompetent 39-year-old male with an LVAD and an implantable cardiac device (ICD) who developed fatal Scedosporium apiospermum fungaemia. To the best of our knowledge, this is the first reported case of LVAD-related S. apiospermum fungaemia.
Background: Restrictive mitral annuloplasty is the mainstay of surgical correction of chronic isc... more Background: Restrictive mitral annuloplasty is the mainstay of surgical correction of chronic ischaemic mitral regurgitation (CIMR). Long-term data on the various types of annuloplasty rings is limited. The aim of this study was to investigate the clinical and echocardiographic outcomes of restrictive mitral annuloplasty in patients with CIMR, comparing the use of flexible versus semi-rigid annuloplasty rings. Methods: A retrospective review was conducted for 133 patients with CIMR who underwent restrictive mitral annuloplasty at our institution between 1999 and 2015. Patient demographics and postoperative outcomes were analyzed. Results: Mean age was 61.9±9.2 years and 103 patients (77.4%) were male. All patients underwent coronary artery bypass grafting, with a mean of 3.3±0.8 grafts. Flexible rings was implanted in 39 patients (29.3%, group F) and semi-rigid rings in 94 (70.7%, group R). Preoperative New York Heart Association class was III/IV in 104 patients (78.2%). Mean preoperative left ventricular ejection fraction was 28.8%±10.2%. Preoperative mitral regurgitation was moderate in 51 patients (38.3%) and severe in 82 (61.7%). In-hospital mortality occurred in 11 patients (8.3%). Overall survival at 1, 5 and 10 years were, respectively, 86.4%, 69.7% and 45.9%. At 10 years, overall survival (group F 53.1%, group R 40.0%, P=0.330) and freedom from moderate to severe MR (group F 53.1%, group R 53.8%, P=0.725) did not differ significantly. Freedom from hospitalization for heart failure was 59.3%. Left ventricular reverse remodelling, defined as a reduction of left ventricular end-systolic volume index >15%, occurred more commonly in Group R (51.1%) compared to Group F (23.1%), P=0.003. Conclusions: Restrictive mitral annuloplasty was associated with an operative mortality of 8.3%. Heart failure symptoms and significant MR recur in approximately 40% of patients after 10 years. Survival remained suboptimal and was not influenced by the type of annuloplasty ring.
Background: ACRE pathway was implemented at TUH in October 2018. The aim of this study was to ana... more Background: ACRE pathway was implemented at TUH in October 2018. The aim of this study was to analyse its impact on exercise stress test (EST) referrals in TUH. Methods: Retrospective analysis of 558 emergency department (ED) chest pain presentations was done over six months, including the appropriateness of risk stratification and referrals for EST, waiting time for EST, and representations to ED whilst awaiting EST. Results: Of the 558 ED presentations, 76.7% had risk category documented appropriately. Only 48.4% of the intermediate risk patients were referred for an outpatient EST from ED. Of the 132 EST referrals, the median waiting period was 4 weeks, with 51 (39%) completed within 2 weeks. There were 91 representations to ED while waiting for EST, and 48 (54%) of those patients were discharged from ED. Conclusion: As expected, implementing change to accelerated diagnostic protocol significantly increased the EST referrals.
Background: Vascular Endothelial Dysfunction (VED) plays a fundamental role in the pathophysiolog... more Background: Vascular Endothelial Dysfunction (VED) plays a fundamental role in the pathophysiology of a number of cardiovascular disease states, including atherosclerosis, acute coronary syndromes/myocardial infarction, hypertension and heart failure. These cardiovascular disease states have also been linked with physical frailty and sarcopenia. Elevated inflammatory status and oxidative stress have been associated with both cardiovascular diseases states and physical frailty, although the exact pathophysiological mechanisms linking the two conditions remain largely unknown. We hypothesize that inflammation-related pathological changes in the vascular endothelium may result in VED, which in turn result in cardiovascular disease states and thus frailty and sarcopenia. Aim: To delineate a possible association between VED and frailty/sarcopenia. Method: A systematic literature review was performed according to PRISMA principles to identify relevant published studies between January 2000 to August 2019. Only original human or animal research studies in English language were included. Results: Twenty-five studies were eligible for inclusion. VED is independently associated with increased frailty phenotypes and measures of sarcopenia. Several markers of VED, including elevated levels of asymmetric dimethylarginine, homocysteine, abnormal ankle brachial index, pulse wave velocity, pulse pressure and lower levels of flowmediated dilatation, peripheral blood flow, endothelial progenitor cells and s-klotho protein have been associated with higher levels of physical frailty and sarcopenia measurements with some studies demonstrating the role of inflammation in modulating this association. Conclusions: VED may potentially be an early marker of sarcopenia and frailty, although the exact mechanism(s) underlying the association between VED and sarcopeniarelated physical frailty have yet to be delineated.
Interactive Cardiovascular and Thoracic Surgery, Oct 25, 2019
A best evidence topic in cardiac surgery was written according to a structured protocol. The ques... more A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Does concurrent use of intra-aortic balloon pump (IABP) improve survival in patients with cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation (VA-ECMO)?'. Altogether 472 papers were found using the reported search, of which 3 level 2 systematic reviews represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The reported comparative outcomes were mortality, weaning off extracorporeal membrane oxygenation (ECMO), vascular complications and non-vascular complications. One systematic review demonstrated significantly lower in-hospital mortality with concurrent use of IABP and VA-ECMO, while the other 2 studies showed no difference in mortality. One paper reported on the weaning success from ECMO and demonstrated significantly higher weaning success with concurrent IABP usage. Another paper reported on the complications and showed no differences in vascular and non-vascular complications. We conclude that there was no significant improvement in survival with the concurrent use of IABP and VA-ECMO for a cardiogenic shock as compared to the use of VA-ECMO alone. However, the concurrent use of IABP with VA-ECMO improved weaning success from VA-ECMO. The incidence of vascular and non-vascular complications was similar with or without IABP usage.
A telecare project has been established which allows outpatients to monitor their own health with... more A telecare project has been established which allows outpatients to monitor their own health with the assistance of SingHealth clinicians. Communication takes place through a Web portal and/or by mobile phone text messaging (SMS). The pilot service has been used by local and overseas patients with chronic diseases such as heart failure, hypertension, renal failure, diabetes and suspected occupational asthma. Through the telecare system, which was developed in-house, clinicians can configure a personalized monitoring plan (vital signs and symptoms) for each patient and follow up with interactive charts. The patient's health data are transmitted to the telecare system by the patient or care-giver, through a Web portal or by SMS messages. If a patient's health indicators fall outside predefined thresholds, clinicians can be alerted by SMS. Patients and clinicians can also communicate through the portal. Apart from chronic disease management, the system has also been used to rep...
The Malaysian Journal of Medical Science, Jun 27, 2023
Background: Intracerebral haemorrhage (ICH) can be devastating, particularly if haematoma expansi... more Background: Intracerebral haemorrhage (ICH) can be devastating, particularly if haematoma expansion occurs. The efficacy of tranexamic acid (TXA), an anti-fibrinolytic agent, in reducing haematoma expansion is now being studied worldwide. However, the optimal dosage of TXA has yet to be determined. This study was designed to further establish the potential of different doses of TXA. Methods: A double-blinded, randomised, placebo-controlled study was carried out among adults with non-traumatic ICH. Eligible study subjects were randomly assigned to receive placebo, 2-g TXA treatment or 3-g TXA treatment. Haematoma volumes before and after intervention were measured using the planimetric method. Results: A total of 60 subjects with 20 subjects in each treatment group were recruited for this study. Among the 60 subjects, the majority were male (n = 36, 60%), had known cases of hypertension (n = 43, 71.7%) and presented with full Glasgow coma scale (GCS) (n = 41, 68.3%). The results showed that there was no statistically significant difference (P = 0.315) in the mean changes of haematoma volume when compared with three study groups using ANCOVA, although the 3-g TXA group was the only group that showed haematoma volume reduction (mean reduction of 0.2 cm 3) instead of expansion as in placebo (mean expansion 1.8 cm 3) and 2-g TXA (mean expansion 0.3 cm 3) groups. Good recovery was observed in all study groups, with only three subjects being moderately disabled. No adverse effects were reported in any of the study groups. Conclusion: To the best of our knowledge, this is the first clinical study using 3 g of TXA in the management of non-traumatic ICH. From our study, 3 g of TXA may potentially be helpful in reducing haematoma volume. Nonetheless, a larger-scale randomised controlled trial should be carried out to further establish the role of 3 g of TXA in non-traumatic ICH.
Saksenaea vasiformis complex is an emerging cause of mucormycosis. We report a case of an immunoc... more Saksenaea vasiformis complex is an emerging cause of mucormycosis. We report a case of an immunocompetent patient presenting with a nonresolving lung mass who developed multiple skin nodules. Skin biopsy yielded Saksenaea vasiformis complex. This showcases an uncommon occurrence of disseminated Saksenaea infection without cutaneous inoculation that improved with posaconazole.
The Journal of Heart and Lung Transplantation, 2021
Purpose The incidence of driveline fractures among patients on HeartMate II Left Ventricular Assi... more Purpose The incidence of driveline fractures among patients on HeartMate II Left Ventricular Assist Device (LVAD) support is reviewed Methods This is a single-center, retrospective review of all the patients on HeartMate II LVAD support who presented with driveline fractures. Patients’ presentation, interventions, and outcome following corrective treatment were examined. Results Between May 2009 and October 2018, 60 HeartMate II LVAD were implanted. Over a cumulative support period of 81 patient-years (maximum, 8.5 years), 15 patients (25%) had driveline fractures (age 14-70, 2 female), 5 of them were destination therapy (> 65 years old). Mean duration from the time of implant to driveline fractures was 44.5 ± 15.5 months. 12 patients had significant weight gain following LVAD implant, ranging from 5.2 to 32.3kg (median 17.4kg). While tethered on to power module, 8 patients (53.3%) encountered intermittent pump stoppage, 5 (33.3%) had transient low pump speed, 1 (6.7%) had recurrent driveline fault and 1 more (6.7%) presented with hemoserous discharge leaking from broken insulation in the external driveline with multiple recurrent low voltage advisory. Ungrounded cable was issued to 13 patients as a temporary measure with mean duration of its usage of 259 days (range 26-980 days), before corrective treatment. There were 2 patients with ongoing use of the ungrounded cable (mean 1 year). 8 patients (53.3%) underwent pump replacement, 2 with significant external driveline fractures successfully underwent external driveline replacement and 1 underwent heart transplant. Of the 9 pumps returned for analysis, 7 (78%) were found to have damaged internalized part of the driveline while 2 (22%) had circumferential fractures at the edge of the pump housing extending across the diameter of the bend relief. There were 3 mortality (20%), 1 due to recurrent pump pocket infection and pump thrombosis following the initial pump replacement for driveline fractures, 1 died of subdural haemorrhage before elective pump exchange and 1 died 3 weeks after pump stoppage. Conclusion The incidence of HeartMate II internal driveline fractures seemed to be higher in our Asian experience as opposed to what have been reported in literature. An ungrounded cable served as a temporary measure for short to shield and a timely pump exchange maybe lifesaving when driveline damage progressed into phase to phase.
The Journal of Heart and Lung Transplantation, 2019
Purpose: Very little is known about frailty in patients with a left ventricular assist device (LV... more Purpose: Very little is known about frailty in patients with a left ventricular assist device (LVAD) in general, and about reversibility of different measures of frailty post LVAD in particularly. The purpose of the study was to determine which measures of frailty improve post LVAD implantation. Methods: This was an observational, longitudinal (3 month) cohort study of 25 patients with advanced heart failure who underwent LVAD implantation between January 2015 and May 2016. Demographic and clinical data were retrieved from hospital medical records. The six minute walk test (6MWT) was conducted by physical therapist and hand grip strength was assessed by a nurse practitioner using a hand dynamometer. Paired t-test was used to determine differences between pre and post 6MWT, handgrip strength and serum albumin levels. Demographic and clinical characteristics were reported using frequencies, percentages for categorical variables and mean § standard deviation for continuous variables. Results: A majority of the patients were male (88%) and over 40% of the patients in the study were under the age of 60. The primary etiology of heart failure for his population was ischemic cardiomyopathy (60%). Complete data were collected on 23 patients. One patient died within 3 months of LVAD implant and one patient was wheelchair bound post LVAD implant. The mean pre-operative albumin level was 2.7 § .4 mg/dL with only 4% of patients having an albumin levels > 3.5 mg/dl. The albumin became normal after surgery (see Table). Only 8% of patients walked 300 feet or more in 6 minutes pre-implant. In contrast 53% were able to walk more than 300 feet at 3 months post-implant. There was no difference in hand grip strength. Conclusion: Albumin levels and 6MWT significantly improved 3 months post LVAD implant, while hand grip strength noted no improvement. Short 6MWT distance and low albumin should not preclude LVAD implant because these measures of frailty are reversible and are likely to improve shortly after surgery. Pre implant and Post implant Frailty Measures Frailty Measure Pre I mplant 3 Months Post Implant p value Hand grip strength 22.8 § 10.7 24.7 § 11.1 .06 Six minute walk (feet) 186 § 83.2 275 § 121.1 <.001 Albumin (mg/dl) 2.7 § .4 3.5 § .4 <.001
The Journal of Heart and Lung Transplantation, 2019
baloon pump preoperatif period. TAPSE was 13.4 §3.2 (7-20) mm, right ventricle FAC was 25 % § 7 (... more baloon pump preoperatif period. TAPSE was 13.4 §3.2 (7-20) mm, right ventricle FAC was 25 % § 7 (10-40). Mean INTERMACS was 2,8 §0,7 (1-4). The average cardiopulmonary bypass durations was 86,5,2 +/-29,7 min (range: 12-141). Peroperative red blood cell transfusion 1.6 § 1.4 (0-5) Unite, early right ventricular failure was 10.1%, mean mechanical ventilation time 2.1 § 2,5 8 1-15 days, intensive care unit length of stay was 7,3 §4,2 (1-16) days. At 443,7 days mean follow up time 82,5% survival was observed. The most common adverse event on device was driveline infection (18,3%). Gastrointestinal bleeding was 2%, hemorrhagic cerebrovascular event was 8%, pump trombosis 10,2%, late right ventricle failure 5%, hemorrhagic cerebrovascular event was 8%. Eleven patients (22,4%) were transplanted. Conclusion: Minimally invasive implantation of left ventricular assist devices both of two pump HeartWar (HVAD) and Heartmate 3 is safely feasible. After a very good initial experience with this technique it has become the method of choice in our department.
The Journal of Heart and Lung Transplantation, 2016
appears to be primarily a result of reduced serum albumin in this population (mean albumin 3.0 ± ... more appears to be primarily a result of reduced serum albumin in this population (mean albumin 3.0 ± 0.47 g/dL). It appears that low albumin levels and labile fluid status may render the NRI an ineffective means of assessing post-operative outcomes in AHF patients undergoing LVAD.
The Journal of Heart and Lung Transplantation, 2017
and received antibiotics, of which 61 (16%) were readmitted for DLIs and 27 (7%) required surgica... more and received antibiotics, of which 61 (16%) were readmitted for DLIs and 27 (7%) required surgical intervention. The most common pathogens in the surgery group were Pseudomonas Aeruginosa (26%), Methicillin-resistant Staphylococcus aureus (22%) and Methicillin-sensitive Staphylococcus aureus (19%). No individual surgical technique achieved higher rates of healing compared to others. The NPVD group included 90 patients with a follow-up of nearly 12 months. Fifteen patients (17%) were treated for DLIs, of which 7 (7%) required surgical intervention. There was a trend towards reduced total DLIs in the NPVD group (p< .09). Conclusion: DLIs continue to be a challenging and morbid complication, affecting nearly 25% of our patients. Although there was no significant difference in the healing rates between various surgical techniques, it does appear that the application of NPVD at the time of implantation might reduce the incidence of DLIs. Long-term follow-up and increased study size is needed to more fully define the efficacy of this intervention.
The Journal of Heart and Lung Transplantation, 2017
Increasingly Extracorporeal Membrane Oxygenation (ECMO) is being used as a bridge to decision for... more Increasingly Extracorporeal Membrane Oxygenation (ECMO) is being used as a bridge to decision for recovery, transplantation or to a durable left ventricular assist device (LVAD) for patients presenting with cardiogenic shock. We report our outcomes in INTERMACS I patients receiving a durable LVAD after bridging with ECMO. Methods: A retrospective review of 20 consecutive INTERMACS profile I patients who were bridged from ECMO support to continuous-flow LVAD between May 2009 and September 2016 in Singapore was performed in order to evaluate our outcomes based on our management protocol. Results: 16 were males. The aetiologies include acute coronary syndrome in 12 (60%), dilated cardiomyopathy in 4 (23%), myocarditis in 3 (15%) and ischemic cardiomyopathy in 1 (5%). Mean age at the time of LVAD implant was 40 (± 14) years old. The total length of LVAD support was 33 patient months. Twelve patients received HeartMate II LVAD and two received HeartMate III LVAD. Six received HeartWare LVAD. Majority (18, 90%) were BTT while two were DT (10%). Median duration of ECMO support was 10 days (range 1-23). Mean length of hospital stay following LVAD implant was 50 days (range 15-99). There was is no in-hospital mortality. Kaplan Meier survival at 1-year was 100% and 91.7% at 3-years. Following LVAD implantation, four (20%) received cardiac transplant and one (5%) had LVAD explant following myocardial recovery. Conclusion: Our zero peri-operative mortality in this high risk group suggests that our management protocol is valid. The 3-years survival too appears to be favourable compared to INTERMACS registry data.
Discussing the most challenging clinical cases / New invasive therapies and devices: reality or s... more Discussing the most challenging clinical cases / New invasive therapies and devices: reality or science fiction? 1131 3498 Alcohol septal ablation as a treatment of left ventricular outflow tract obstruction after mitral valve repair
European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery, 2015
OBJECTIVES To review our experience of surgical management of infective endocarditis (IE) over a ... more OBJECTIVES To review our experience of surgical management of infective endocarditis (IE) over a 13-year period and analyse the outcomes and associated prognostic factors. METHODS A retrospective review was conducted for 191 consecutive patients who underwent surgery for native and prosthetic valve endocarditis (PVE) between January 2000 and December 2012. Surgical outcomes were reviewed to include survival and postoperative complications. Follow-up was complete for 172 of 179 patients (96.1%) surviving to hospital discharge, with a mean follow-up of 6.6 ± 3.7 years. RESULTS Mean age was 47.4 ± 14.9 years with 113 (63.9%) males. Native valve endocarditis was present in 177 patients (92.7%). Sixty-three patients (33.0%) presented with embolic complications. The brain was the most common site of embolism, involving 25 patients (13.1%). Streptococcus viridans was the most common infective organism, isolated in 68 patients (35.7%), followed by Staphylococcus aureus in 30 patients (15.7%...
Limited data exists on patients receiving therapeutic hypothermia during extracorporeal life supp... more Limited data exists on patients receiving therapeutic hypothermia during extracorporeal life support (ECLS). We investigated outcomes and prognostic factors in these patients. A retrospective review was conducted for 225 consecutive adult patients treated with ECLS between July 2003 and January 2016. Extracorporeal life support was initiated for refractory cardiac arrest (>10 mins) in 79 patients (35.1%). Patient demographics, ECLS-related complications, in-hospital mortality and neurological outcomes were analysed. The mean age was 49.9±12.4 years. Sixty-two patients (78.5%) were male. The mean duration of CPR and ECLS were respectively, 32.0±23.3 mins and 5.4±4.0 days. Therapeutic hypothermia (34(o)C) was maintained for 24hours in 14 patients (17.7%). Thirty-five patients (44.3%) were weaned off ECLS. Twenty-one patients (26.6%) survived to hospital discharge with 16 (20.3%) recovering good neurological function. Compared to ECLS at normothermia, neurologically favourable survi...
Introduction: In November 2016, surgical antibiotic prophylaxis (SAP) guidelines for cardiothorac... more Introduction: In November 2016, surgical antibiotic prophylaxis (SAP) guidelines for cardiothoracic surgeries at the authors’ centre were updated. SAP was reduced from 48 to 24 hours, and dual cover with vancomycin and cefazolin instead of vancomycin monotherapy was recommended for patients colonised with methicillin-resistant Staphylococcus aureus. This study was conducted to review compliance to the updated guidelines, and compare the incidence of surgical site infections (SSI). Methods: A list of patients undergoing sternotomy in National Heart Centre, Singapore, from March 2016 to February 2019 was extracted from the hospital’s electronic database; every fourth patient was included in the analysis. The patients were divided into three groups: Group 1 (before guideline revision, March–October 2016), Group 2 (post-guideline implementation, July 2017–May 2018), and Group 3 (July 2018–February 2019). Compliance to guidelines, incidence, and epidemiology of SSIs within 90 days of sur...
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