Clinical and neurocognitive outcomes after transcatheter aortic valve implantation (TAVI) with cerebral protection: initial experience with a novel dual-filter device in Southeast Asia.

INTRODUCTION: Transcatheter aortic valve implantation (TAVI) is increasingly performed in patients with severe aortic stenosis. A novel dual-filter system to reduce cerebral embolism during TAVI recently became available. We aimed to assess the feasibility, safety, and clinical and neurocognitive outcomes of TAVI with cerebral protection in Asian patients. METHODS: 40 consecutive patients undergoing TAVI with cerebral protection were enrolled. All procedures were performed via femoral access using the self-expanding Evolut R/PRO or Portico, or the balloon-expandable SAPIEN 3 bioprostheses. Baseline characteristics, procedural and clinical outcomes were recorded. Cognition was assessed at baseline and 30 days using the abbreviated mental test (AMT). RESULTS: The mean age of the patients (75% male) was 76.4 ± 8.4 years. TAVI was uncomplicated in all patients. The filter device was successfully deployed in 38 (95.0%) patients without safety issues. There was no stroke or death at 30 days, and the survival rate at nine months was 95.0%. There was no overall cognitive change (baseline vs. 30-day AMT: 9.2 ± 1.1 vs. 9.0 ± 1.5, p = 0.12), and only 1 (2.5%) patient developed impaired cognition at 30 days. Patients with a decreased AMT score at 30 days were significantly older than those without (82.1 ± 4.5 vs. 74.4 ± 7.7 years, p = 0.019). All patients with decreased AMT scores were aged ≥ 76 years. CONCLUSION: In this early Asian experience of TAVI under cerebral protection, the filter device was successfully deployed in 95% of patients, with 100% procedural success. There were no filter-related complications and no stroke or mortality at 30 days. Overall cognition was preserved, although increased age was associated with a decline in AMT score.

Two-year outcome of ventricular assist device via a modified left atrium to aorta approach in cardiac amyloidosis.

Cardiac amyloidosis is a debilitating disease associated with poor long-term survival. Medical or palliative treatment is the usual course of therapy, but patients are often intolerant of conventional heart failure treatment. The current standard of care of sequential heart and bone marrow transplant is usually not feasible for ill or frail patients or in countries with limited organ donors or without transplant programmes. Left ventricular assist devices (LVAD) are not usually offered to these patients due to high peri-operative risks and risks of suction events with the LVAD in a small left ventricle. We report the 2 year outcome and discuss the challenges faced in the management of our patient with end-stage heart failure due to cardiac amyloidosis, who was successfully supported with an LVAD using a modified left atrium to aorta implantation technique.

Staphylococcal driveline infections are the predominant type of left ventricular assist device associated infections in Singapore.

BACKGROUND: Left ventricular assist device (LVAD) associated infections (LVADIs) have substantial morbidity and mortality. We aim to describe the incidence and epidemiology of LVADIs in an Asian cohort. This is currently not well studied. METHODS: We conducted a retrospective review of 52 patients who underwent LVAD implantation from 1 May 2009-31 December 2014 in National Heart Centre Singapore. LVADIs were defined based on definitions proposed by the International Society for Heart and Lung Transplantation. RESULTS: There were 39 males and 13 females. Seventy-three percent had Heartmate II LVAD implant while 27% received Heartware HVAD. Eighty-one percent were implanted as bridge to heart transplantation, 19% as destination therapy. Forty-five episodes of LVADIs occurred in 25 patients. Overall LVADI incidence was 47.5 cases per 100 patient-years. Driveline infections (58%) were the commonest type of LVADI. The commonest causative organisms were coagulase-negative staphylococci (33%), Staphylococcus aureus (31%) and Corynebacterium species (19%). Twelve percent of patients with LVADI required surgical debridement and one patient required pump exchange due to pump pocket infection. All-cause mortality was 13%. CONCLUSIONS: The findings of our study add to the understanding and epidemiology of LVADIs, particularly in the Asian setting. This can contribute to the development of evidence based strategies to prevent and manage LVADIs.

Mortality outcome and predictive risk factors for death in patients with heart failure and reduced ejection fraction who declined implantable cardioverter defibrillator implantation in Singapore.

BACKGROUND: There have been conflicting data regarding the risk of sudden cardiac death (SCD) in Asian population with reduced left ventricular ejection fraction (LVEF). We aim to study mortality outcome and its risk predictors in patients with reduced LVEF who declined an implantable cardioverter defibrillator (ICD) implantation and assess whether current ICD guidelines for primary prevention are applicable to the population in Singapore. METHODS: This prospective observational study involved 240 consecutive patients who fulfilled the ACC/AHA/HRS criteria for ICD implantation for primary prevention of SCD but declined ICD implantation. Baseline characteristics and mortality outcomes through May 2017 were collected via case-note review after a mean follow-up of 44.8 ± 16.6 months. RESULTS: Majority of our patients were Chinese (71.3%), followed by Malays (16.2%) and Indians (10.8%). Mean age (±SD) was 61 ± 10 years, and 84% were male. Majority were in New York Heart Association (NYHA) functional classes I (46.7%) and II (46.3%). Over a mean follow-up of 44.8 ± 16.6 months, all-cause mortality rate was 34.6%. Diabetes mellitus (HR = 1.57; 95% CI, 1.01-2.44; P = 0.047) and chronic kidney disease (CKD; HR = 1.95; 95% CI, 1.17-3.23; P = 0.010) were independent predictors of mortality. Patients in NYHA classes II (HR = 2.15; 95% CI, 1.32-3.50; P = 0.002) and III (HR = 2.82; 95% CI, 1.34-5.96; P = 0.007) showed higher risk of death. CONCLUSION: The mortality rate was comparable with major primary prevention trials. ICD guideline recommendations for primary prevention may thus be applicable to our local population. Patients with diabetes, CKD, and poorer NYHA status exhibited higher mortality rates.

Effect of multimorbidity on survival of patients diagnosed with heart failure: a retrospective cohort study in Singapore.

OBJECTIVE: Multimorbidity in patients with heart failure (HF) results in poor prognosis and is an increasing public health concern. We aim to examine the effect of multimorbidity focusing on type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD) on all-cause and cardiovascular disease (CVD)-specific mortality among patients diagnosed with HF in Singapore. DESIGN: Retrospective cohort study. SETTING: Primary and tertiary care in three (out of six) Regional Health Systems in Singapore. PARTICIPANTS: Patients diagnosed with HF between 2003 and 2016 from three restructured hospitals and nine primary care polyclinics were included in this retrospective cohort study. PRIMARY OUTCOMES: All-cause mortality and CVD-specific mortality. RESULTS: A total of 34 460 patients diagnosed with HF from 2003 to 2016 were included in this study and were followed up until 31 December 2016. The median follow-up time was 2.1 years. Comorbidities prior to HF diagnosis were considered. Patients were categorised as (1) HF only, (2) T2DM+HF, (3) CKD+HF and (4) T2DM+CKD+HF. Cox regression model was used to determine the effect of multimorbidity on (1) all-cause mortality and (2) CVD-specific mortality. Adjusting for demographics, other comorbidities, baseline treatment and duration of T2DM prior to HF diagnosis, 'T2DM+CKD+HF' patients had a 56% higher risk of all-cause mortality (HR: 1.56, 95% CI 1.48 to 1.63) and a 44% higher risk of CVD-specific mortality (HR: 1.44, 95% CI 1.32 to 1.56) compared with patients diagnosed with HF only. CONCLUSION: All-cause and CVD-specific mortality risks increased with increasing multimorbidity. This study highlights the need for a new model of care that focuses on holistic patient management rather than disease management alone to improve survival among patients with HF with multimorbidity.

Percutaneous Decommissioning of Left Ventricular Assist Device.

BACKGROUND: The left ventricular assist device (LVAD) has revolutionised our treatment of advanced stage heart failure, giving debilitated patients a new lease on life. A small proportion of these LVAD patients can be bridged-to-recovery. The identification of these patients and decision to wean, however, can be challenging. METHODS: The need to fully explant the device upon recovery has evolved to a minimalist approach aiming to avoid injury to the 'recovered' heart. A review of the evolution of explant strategies was performed to guide our decision to wean the LVAD in our early experience. RESULTS: Between 2009 and 2014, two patients in our series of 69 LVAD implants (2.9%) were successfully weaned off their LVADs. The second patient had a minimal access implantation of his HeartWare Ventricular Assist Device (HVAD, Medtronic Inc, Framingham, MA, USA). His clinical variables and minimalist weaning strategy are described. CONCLUSIONS: A case of LVAD decommissioning by thrombosis of the outflow graft, using percutaneous Amplatzer Vascular Plug II (St. Jude Medical, St. Paul, MN, USA) without surgery is reported.

Novel Use of Thalidomide in Recurrent Gastrointestinal Tract Bleeding in Patients with Left Ventricular Assist Devices: A Case Series.

BACKGROUND: Bleeding is an important and common complication of left ventricular assist devices (LVADs). One of the common causes of gastrointestinal bleeding is arteriovenous malformations. However, the source of bleeding is often hard to identify. Thalidomide is efficacious in treatment of gastrointestinal (GI) bleeding in non-LVAD patients. We report our experience of the use of thalidomide in the treatment of GI bleeding in four patients with LVAD. METHOD AND RESULTS: Four patients who had recurrent GI bleeding from May 2009 to December 2014 were started on thalidomide. All of them responded to treatment and had no further gastrointestinal bleeding while on thalidomide. One patient developed constipation, requiring thalidomide to be stopped. Another patient developed symptomatic neuropathy, that resolved with reduction of dosage. CONCLUSION: Thalidomide appears safe and efficacious in LVAD patients with recurrent gastrointestinal bleeding.

Mechanical circulatory support and heart transplantation in the Asia Pacific region.

Globalization has resulted in epidemiologic transition in developing countries from infectious disease and nutritional deficiencies to non-communicable diseases. Epidemiologic data on heart failure (HF), particularly advanced HF therapy, in Asia are increasingly becoming available, although they remain sparse. Heart transplantation for advanced stage HF remains very low in Asia-approximately 0.075 heart transplants per 1 million population. North America, which comprises 7.5% of the world population, accounted for 55.8% of transplants recorded in the 2012 International Society for Heart and Lung Transplantation (ISHLT) Registry, whereas Asia, with 62.5% of the world population, accounted for 5.7% of transplants. There is also lack of reporting from heart transplant centers in Asia to the ISHLT Registry. Most transplant programs in Asia are in economically stable South East Asian countries, whereas in other parts of developing countries, the cost and health care infrastructures remain prohibitive for the development of these programs. Multi-cultural and racial factors, religious beliefs, and diverse traditions of many centuries have resulted in reluctance to organ donation. Mechanical circulatory support (MCS) is emerging as a viable alternative to transplantation, but despite technical capabilities, limitations in embracing MCS in Asia exist. Discrepant practices in the reimbursement of costly MCS therapy have led to differences in the availability of these devices to patients in the region. The HeartMate II (St. Jude Medical, Inc, St. Paul, MN) left ventricular assist device is currently the most widely used durable device in Asia, whereas the HeartWare HVAD (HeartWare, Inc, Framingham, MA) is used most often in Australia. By September 9, 2015, 341 HeartMate implants (293 as bridge to transplant and 48 as destination therapy) had been performed, of which 180 implants were in Japan. The overall 4-year survival is 88%. The longest duration of support is 6.5 years. By the end of 2015, 243 HeartWare HVADs had been implanted in Asia Pacific. There is a need for focused efforts at improving the reporting of data and intensifying health policy within the region to advocate organ transplantation. Individual governments need to take national responsibility to fulfill organ donation and transplantation needs of their populations. International collaboratives, coordinated by societies such as the ISHLT, will be essential in moving this field forward in Asia Pacific.

Patient barriers to implantable cardioverter defibrillator implantation for the primary prevention of sudden cardiac death in patients with heart failure and reduced ejection fraction.

INTRODUCTION: Device therapy is efficacious in preventing sudden cardiac death (SCD) in patients with reduced ejection fraction. However, few who need the device eventually opt to undergo implantation and even fewer reconsider their decisions after deliberation. This is due to many factors, including unresolved patient barriers. This study identified the factors that influenced patients' decision to decline implantable cardioverter defibrillator (ICD) implantation, and those that influenced patients who initially declined an implant to reconsider having one. METHODS: A single-centre survey was conducted among 240 patients who had heart failure with reduced ejection fraction and met the ICD implantation criteria, but had declined ICD implantation. RESULTS: Participants who refused ICD implantation were mostly male (84%), Chinese (71%), married (72%), currently employed (54%), and had up to primary or secondary education (78%) and monthly income of < SGD 3,000 (51%). Those who were more likely to reconsider their decision were aware that SCD was a consequence of heart failure with reduced ejection fraction, knowledgeable of the preventive role of ICDs, currently employed and aware that their doctor strongly recommended the implant. Based on multivariate analysis, knowledge of the role of ICDs for primary prophylaxis was the most important factor influencing patient decision. CONCLUSION: This study identified the demographic and social factors of patients who refused ICD therapy. Knowledge of the role of ICDs in preventing SCD was found to be the strongest marker for reconsidering ICD implantation. Measures to address this information gap may lead to higher rates of ICD implantation.

Ultrafiltration in patients with decompensated heart failure and diuretic resistance: an Asian centre's experience.

INTRODUCTION: Diuretics are the mainstay of therapy for restoring the euvolaemic state in patients with decompensated heart failure. However, diuretic resistance remains a challenge. METHODS: We conducted a retrospective cohort study to examine the efficacy and safety of ultrafiltration (UF) in 44 hospitalised patients who had decompensated heart failure and diuretic resistance between October 2011 and July 2013. RESULTS: Among the 44 patients, 18 received UF (i.e. UF group), while 26 received diuretics (i.e. standard care group). After 48 hours, the UF group achieved lower urine output (1,355 mL vs. 3,815 mL, p = 0.0003), greater fluid loss (5,058 mL vs. 1,915 mL, p < 0.0001) and greater weight loss (5.0 kg vs. 1.0 kg, p < 0.0001) than the standard care group. The UF group also had a shorter duration of hospitalisation (5.0 days vs. 9.5 days, p = 0.0010). There were no differences in the incidence of 30-day emergency department visits and rehospitalisations for heart failure between the two groups. At 90 days, the UF group had fewer emergency department visits (0.2 vs. 0.8, p = 0.0500) and fewer rehospitalisations for heart failure (0.3 vs. 1.0, p = 0.0442). Reduction in EQ-5D™ scores was greater in the UF group, both at discharge (2.7 vs. 1.4, p = 0.0283) and 30 days (2.5 vs. 0.3, p = 0.0033). No adverse events were reported with UF. CONCLUSION: UF is an effective and safe treatment that can improve the health outcomes of Asian patients with decompensated heart failure and diuretic resistance.

Bariatric Surgery Provides a "Bridge to Transplant" for Morbidly Obese Patients with Advanced Heart Failure and May Obviate the Need for Transplantation.

BACKGROUND: In patients with advanced heart failure, morbid obesity is a relative contraindication to heart transplantation due to higher morbidity and mortality in these patients. METHODS: We performed a retrospective analysis of consecutive morbidly obese patients with advanced heart failure who underwent bariatric surgery for durable weight loss in order to meet eligibility criteria for cardiac transplantation. RESULTS: Seven patients (4 M/3 F, age range 31-56 years) with left ventricular ejection fraction (LVEF) ≤ 25 % underwent laparoscopic bariatric surgery. Median preoperative body mass index (BMI) was 42.8 kg/m(2) (range 37.5-50.8). There were no major perioperative complications in six of seven patients. Median length of hospital stay was 5 days. There was no mortality recorded during complete patient follow-up. At a median follow-up of 406 days, median BMI reduction was 12.9 kg/m(2) (p = 0.017). Postoperative LVEF improved to a median of 30 % (interquartile range (IQR) 25-53 %; p = 0.039). Two patients underwent successful cardiac transplantation. Two patients reported symptomatic improvement with little change in LV function and now successfully meet listing criteria. Three patients showed marked improvement of their LVEF and functional status, thus removing the requirement for transplantation. CONCLUSIONS: Bariatric surgery can achieve successful weight loss in morbidly obese patients with advanced cardiac failure, enabling successful heart transplantation. In some patients, cardiac transplantation can be avoided through surgical weight loss.

Pump Speed Waveform Analysis to Detect Aortic Valve Opening in Patients on Ventricular Assist Device Support.

As the aortic valve (AV) opens, the pump pressure head remains constant, which is reflected as a "notch/plateau" in pump pressure and flow signals. However, instantaneous flow estimation may be influenced by friction and is particularly difficult in axial pumps. Therefore, a new method to determine the duration of AV opening based on the area under the curve (AUC) of the power spectral density analysis of pump speed signal was developed. Data from patients implanted with HeartWare HVAD left ventricular assist device were studied at different pump speeds, with simultaneous transthoracic echocardiography in two cohorts. In the first group, pump data of 15 patients were used to investigate the ability to discriminate between an open and closed AV. In the second cohort of a further 13 patients, the duration of AV opening was measured from digitized M-mode images, and the relationship between the AV opening time and the new method assessed. In 14 of the initial 15 patients, AV status could be discriminated using only one threshold for all patients. In the second cohort, gradual speed reduction resulted in aortic valve opening in 12 of the 13 patients. The correlation between AV opening duration and AUC was 0.96 ± 0.03. Regression analysis indicated a linear relationship in each of the patients with a small error between the fit and the measured opening time (root mean square error = 11.0 ± 7.6 ms). However, the slopes (69.0 ± 52.8) and intercepts (-31.4 ± 78.0) varied widely between patients. The sensitivity and specificity for the new method using AUC threshold of 0.95 for aortic valve closure was 95% and 91%, respectively. The newly developed method to detect AV opening not only provides information on the AV status during LVAD support (open/closed) but also gives insight into the duration of AV opening. Because the slope of the relationship varies from patient to patient, initial training and adaptation of the method to each patient seems to be required.