Publications by authors named "Cumaraswamy Sivathasan"

21 Publications

  • Page 1 of 1

ECMO in cardiogenic shock and bridge to heart transplant.

Indian J Thorac Cardiovasc Surg 2021 Apr 11;37(Suppl 2):319-326. Epub 2020 Feb 11.

Department of Cardiothoracic Surgery, National Heart Centre Singapore, 5 Hospital drive, Singapore, 169609 Singapore.

Purpose: The aim of this review is to discuss the role of extracorporeal membrane oxygenation (ECMO) in cardiogenic shock and its use to bridge patients to heart transplantation.

Methods And Results: Consideration of published literature reveals indications for ECMO in cardiogenic shock and tools for patient selection, adequate evidence of its efficacy, its advantages when compared with other temporary mechanical circulatory support devices and details of its use as a bridge to decision, bridge to recovery, bridge to bridge (durable ventricular assist device) and bridge to heart transplant.

Conclusion: ECMO is invaluable in treating patients with medically refractory profound cardiogenic shock and allows for cardiac recovery or planning for permanent heart replacement treatments.
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http://dx.doi.org/10.1007/s12055-020-00923-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8062637PMC
April 2021

Percutaneous paravalvular leak repair for severe aortic regurgitation after transcatheter aortic valve implantation (TAVI).

Ann Acad Med Singap 2021 Mar;50(3):274-276

The Heart and Vascular Centre, Mount Elizabeth Hospital, Singapore.

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March 2021

Chugging to silent machines: development of mechanical cardiac support.

Indian J Thorac Cardiovasc Surg 2020 Aug 25;36(Suppl 2):234-246. Epub 2020 Aug 25.

Mechanical Cardiac Support and Transplantation, National Heart Centre, Singapore, Singapore.

The concept of a mechanical device to support failing hearts arose after the introduction of the heart lung bypass machine pioneered by Gibbon. The initial devices were the pulsatile paracorporeal and total artificial heart (TAH), driven by noisy chugging pneumatic pumps. Further development moved in three directions, namely short-term paracorporeal devices, left ventricular assist devices (LVADs), and TAH. The paracorporeal pumps moved in the direction of electrically driven continuous-flow pumps as well as catheter-mounted intracardiac pumps for short-term use. The LVAD became the silent durable electric, implantable continuous-flow pumps. The TAH remains a pneumatically driven pulsatile device with limited application, but newer technology is moving toward electrically operated TAH. The most successful pumps are the durable implantable continuous-flow pumps now taken over by the 3rd-generation pumps for the bridge to transplant and long-term use with significantly improved survival and quality of life. But bleeding including gastrointestinal bleeding, strokes, and percutaneous driveline infections exist as troublesome issues. Available data supports less adverse hemocompatibility of HeartMate 3 LVAD. Eliminations of the driveline will significantly improve the freedom from infections. Restoring physiological pulsatility to continuous-flow pumps is in the pipeline. Development of appropriate right VAD, miniaturization, and pediatric devices is awaited. Poor cost-effectiveness from the cost of LVAD needs to be resolved before mechanical cardiac support becomes universally available as a substitute for heart transplantation.
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http://dx.doi.org/10.1007/s12055-020-01010-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7538531PMC
August 2020

Practical Considerations for Solid Organ Transplantation During the COVID-19 Global Outbreak: The Experience from Singapore.

Transplant Direct 2020 Jun 8;6(6):e554. Epub 2020 May 8.

Department of Infectious Diseases, Singapore General Hospital, Singapore.

The current coronavirus disease 2019 (COVID-19) pandemic has not only caused global social disruptions but has also put tremendous strain on healthcare systems worldwide. With all attention and significant effort diverted to containing and managing the COVID-19 outbreak (and understandably so), essential medical services such as transplant services are likely to be affected. Closure of transplant programs in an outbreak caused by a highly transmissible novel pathogen may be inevitable owing to patient safety. Yet program closure is not without harm; patients on the transplant waitlist may die before the program reopens. By adopting a tiered approach based on outbreak disease alert levels, and having hospital guidelines based on the best available evidence, life-saving transplants can still be safely performed. We performed a lung transplant and a liver transplant successfully during the COVID-19 era. We present our guidelines and experience on managing the transplant service as well as the selection and management of donors and recipients. We also discuss clinical dilemmas in the management COVID-19 in the posttransplant recipient.
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http://dx.doi.org/10.1097/TXD.0000000000001002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7266363PMC
June 2020

Life Beyond Heart Failure-What Are the Long-Term Challenges, Supportive Care Needs, and Views Toward Supportive Care of Multiethnic Asian Patients With Left Ventricular Assist Device and Their Caregivers?

J Pain Symptom Manage 2020 09 3;60(3):577-587.e1. Epub 2020 Apr 3.

Health Services and Systems Research, Duke-NUS Medical School, Singapore, Singapore.

Context: Challenges experienced by patients with the left ventricular assist device (LVAD) and their caregivers during the early period after LVAD implantation are well documented. However, little is known about long-term challenges, supportive care needs, and views toward supportive care of Asian LVAD patients and caregivers.

Objectives: We aimed to explore the experiences of multiethnic Asian LVAD patients and caregivers so as to identify their long-term challenges, supportive care needs, and views toward supportive care.

Methods: Semistructured interviews with LVAD patients and caregivers were conducted based on the grounded theory approach. Participants were purposively recruited from the inpatient and outpatient settings of the National Heart Center Singapore.

Results: A total of 30 patients and 11 caregivers participated. More than half of the participants were Chinese (patients 63%; caregivers 64%). Most patients (83%) were males, whereas most caregivers were females (91%). The median duration on support was 31 months and 46 months for patients and caregivers, respectively. The implantation of the LVAD was a significant milestone in their lives and caused long-term changes in multiple domains (physical, financial, social, psychoemotional, and spiritual). Experiencing permanent and recurrent losses over time was particularly challenging. Participants expressed the need for mutual support between patient and caregiver and connectedness with others and society at large. Participants desired holistic supportive care from their health care team.

Conclusion: Asian LVAD patients and caregivers experienced long-term challenges and had unique supportive care needs. Our findings have implications on the design of future interventions and supportive care models.
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http://dx.doi.org/10.1016/j.jpainsymman.2020.03.022DOI Listing
September 2020

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

Infect Dis (Lond) 2019 06 15;51(6):417-424. Epub 2019 Apr 15.

a Department of Infectious Diseases , Singapore General Hospital , 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.
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http://dx.doi.org/10.1080/23744235.2019.1592216DOI Listing
June 2019

Solid Organ Transplantation in Singapore.

Transplantation 2018 09;102(9):1397-1400

National University Centre for Organ Transplantation, National University Health System, Singapore.

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http://dx.doi.org/10.1097/TP.0000000000002235DOI Listing
September 2018

ECMO and Short-term Support for Cardiogenic Shock in Heart Failure.

Curr Cardiol Rep 2018 08 16;20(10):87. Epub 2018 Aug 16.

Department of Cardiothoracic Surgery, Level 12, National Heart Centre Singapore, 5 Hospital Drive, Singapore, 169609, Singapore.

Purpose Of Review: This review aims to discuss the role of ECMO in the treatment of cardiogenic shock in heart failure.

Recent Findings: Trials done previously have shown that IABP does not improve survival in cardiogenic shock compared to medical treatment, and that neither Impella 2.5 nor TandemHeart improves survival compared to IABP. The "IMPRESS in severe shock" trial compared Impella CP with IABP and found no difference in survival. A meta-analysis of cohort studies comparing ECMO with IABP showed 33% improved 30-day survival with ECMO (risk difference 33%; 95% CI 14-52%; p = 0.0008; NNT 3). ECMO is indicated in medically refractory cardiogenic shock. ECMO can be considered in cardiogenic shock patients with estimated mortality of more than 50%. ECMO is probably the MCS of choice in cardiogenic shock with; biventricular failure, respiratory failure, life-threatening arrhythmias and cardiac arrest.
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http://dx.doi.org/10.1007/s11886-018-1041-4DOI Listing
August 2018

Percutaneous Decommissioning of Left Ventricular Assist Device.

Heart Lung Circ 2018 Jul 19;27(7):853-855. Epub 2017 Aug 19.

Department of Cardiothoracic Surgery, National Heart Centre Singapore, Singapore.

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.
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http://dx.doi.org/10.1016/j.hlc.2017.07.011DOI Listing
July 2018

Asia's First Minimal-Access Left Ventricular Assist Device Implantation.

Ann Acad Med Singap 2017 06;46(6):256-257

Department of Cardiothoracic Surgery, National Heart Centre, Singapore.

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June 2017

Novel use of low-dose thalidomide in refractory gastrointestinal bleeding in left ventricular assist device patients.

Int J Artif Organs 2017 Oct 11;40(11):636-640. Epub 2017 Jul 11.

Department of Cardiology, National Heart Center, Singapore - Singapore.

Background: Gastrointestinal bleeding (GIB) is a complication reported in patients post left ventricular assist device (LVAD) implantation that is associated with high mortality rates. Thalidomide is an anti-angiogenic compound that may offer a potential option for management of refractory LVAD-related GIB.

Methods: A single-center, retrospective review was conducted from January 2009 to October 2016 at a tertiary cardiology center. It included LVAD patients initiated on thalidomide for refractory GIB.

Results: All patients (n = 11) were started on thalidomide 50 mg nocte and there was resolution of GIB in all patients except one (90.9%) during initial thalidomide treatment.The median duration of thalidomide therapy was 98 days (interquartile range: 34-215). The dose of thalidomide was reduced for 2 patients due to adverse effects. Thalidomide therapy was discontinued in 6 patients due to cessation of GIB (n = 4) and adverse effects (n = 2). Reported adverse effects included LVAD thrombosis (n = 2), somnolence (n = 1), neuropathy (n = 1), constipation (n = 1), and transaminitis (n = 1).Recurrent GIB occurred in 4 patients (45.4%) post-discontinuation of thalidomide therapy, which led to the re-initiation of therapy.

Conclusions: Thalidomide appears to be a safe and effective option for management of refractory LVAD-related GIB. Monitoring for recurrent GIB should be performed closely following cessation of thalidomide therapy.
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http://dx.doi.org/10.5301/ijao.5000620DOI Listing
October 2017

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

Heart Lung Circ 2017 Oct 23;26(10):1101-1104. Epub 2016 Dec 23.

National Heart Centre, Singapore.

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.
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http://dx.doi.org/10.1016/j.hlc.2016.11.017DOI Listing
October 2017

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

J Heart Lung Transplant 2017 01 29;36(1):13-18. Epub 2016 Sep 29.

Brigham and Women's Hospital Heart and Vascular Center and Harvard Medical School, Boston, Massachusetts.

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.
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http://dx.doi.org/10.1016/j.healun.2016.09.006DOI Listing
January 2017

"Burnt out" dilated hypertrophic cardiomyopathy causing acute LVAD thrombosis.

Clin Case Rep 2015 Jun 9;3(6):376-8. Epub 2015 Apr 9.

National Heart Centre Singapore.

Case report illustrates obstruction encountered in a patient with end-stage dilated hypertrophic cardiomyopathy (HCM) who underwent LVAD implantation. The morphology reversed in early postoperative period to HCM. Pump replacement required coring of the ventricular muscle. Dilated end-stage hypertrophic cardiomyopathy can revert back to the original morphology on decompression.
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http://dx.doi.org/10.1002/ccr3.237DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4498846PMC
June 2015

Contained Rupture in HeartMate II Outflow Graft Bend Relief Disconnection.

Asian Cardiovasc Thorac Ann 2016 Mar 27;24(3):269-71. Epub 2014 Oct 27.

Department of Cardiothoracic Surgery, National Heart Centre, Singapore.

Thoratec recalled their HeartMate II ventricular assist device in March 2012 after some problems related to disconnection of the bend relief. Abrasion on the pump outflow graft caused by a disconnected bend relief is rare. We report the case of a 49-year-old man in whom a disconnected bend relief caused a puncture in the outflow graft, resulting in a contained hematoma, requiring outflow graft replacement.
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http://dx.doi.org/10.1177/0218492314557871DOI Listing
March 2016

Use of left ventricular assist device (HeartMate II): a Singapore experience.

Artif Organs 2014 Jul 7;38(7):543-8. Epub 2014 Jan 7.

National Heart Centre Singapore, Singapore.

Recent advances in medical and device therapies in heart failure have improved the survival of patients with heart failure. However, due to the limited availability of suitable heart donors, left ventricular assist devices (LVADs) have become an important tool as a bridge-to-heart transplantation for patients with refractory heart failure in Singapore. We report our experience with the HeartMate II (HMII) LVAD (Thoratec Corporation, Pleasanton, CA, USA) as a bridge-to-heart transplant in our center from 2009 to 2012. This was a retrospective review of 23 consecutive patients who underwent HMII LVAD implantation in our center between May 2009 and December 2012. All patients were classified as Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) levels 1 to 3 and underwent LVAD implantation as a bridge-to-heart transplant. There were 17 male and 6 female patients. The mean age was 43.6 years old (range 14 to 64). The etiologies of heart failure included ischemic heart disease [8], idiopathic dilated cardiomyopathy [11], viral myocarditis [2], and chemotherapy-induced cardiomyopathy [2]. Nine patients were INTERMACS level 1, 12 patients level 2, and two patients level 3. All patients successfully underwent HMII LVAD implantation. There was no mortality within the first 30 postoperative days. Postoperative complications included stroke with full neurological recovery (21.7%), mediastinal infection (21.7%), cardiac tamponade or mediastinal collection requiring reopening of the chest (39.1%), cardiac arrhythmia (13.0%), and pump thrombosis with pump replacement (4.3%). All patients were discharged from hospital after LVAD implantation. Three patients experienced driveline infections during outpatient follow-up. There were 19 readmissions due to the following conditions: sub-therapeutic anticoagulation (13.0%), gastrointestinal bleeding (13.0%), suspected pump thrombosis (13.0%), transient ischemic attack (8.7%), arrhythmia (8.7%), congestive cardiac failure due to severe aortic regurgitation (8.7%), right ventricular failure (4.3%), rhabdomyolysis (4.3%), and hematuria (4.3%). Post-LVAD implantation, 20 patients were functionally New York Heart Association (NYHA) class I, while 3 reported NYHA III symptoms. Three patients were successfully bridged to heart transplantation. One patient was successfully explanted 11 months after LVAD implantation. There were two mortalities during the follow-up period. The average duration of LVAD support was 522 days (range 47 to 1316 days). The HeartMate II LVAD has proven to be effective in our Asian population. Driveline infection rate remains low even in the tropical hot, humid climate in Singapore. With more patients ending up on extended periods of LVAD support, increased emphasis in the detection and management of long-term complications of ventricular assist devices will be needed.
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http://dx.doi.org/10.1111/aor.12247DOI Listing
July 2014

Successful clearance of human parainfluenza virus type 2 viraemia with intravenous ribavirin and immunoglobulin in a patient with acute myocarditis.

J Clin Virol 2013 Jan 6;56(1):37-40. Epub 2012 Nov 6.

Department of Infectious Diseases, Singapore General Hospital, Singapore.

Human parainfluenza virus (HPIV) infection as an aetiology of acute viral myocarditis is rare, with only few cases reported in the literature to date. Here we report a case of fulminant HPIV-2 myocarditis in a 47 year-old man with viraemia who was successfully treated with intravenous ribavirin and intravenous immunoglobulin (IVIG). There are currently no recommendations on the treatment of HPIV myocarditis. We are, to our knowledge, the first to report a patient with a documented HPIV-2 viraemia that subsequently cleared after the initiation of antiviral therapy. Although it is difficult to definitively attribute the patient's clinical improvement to ribavirin or IVIG alone, our case does suggest that clinicians may wish to consider initiating ribavirin and IVIG in patients with HPIV myocarditis and persistent viraemia not responding to supportive measures alone.
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http://dx.doi.org/10.1016/j.jcv.2012.10.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7185820PMC
January 2013

Heart transplantation in Singapore.

Ann Acad Med Singap 2009 Apr;38(4):309-6

Heart and Lung Transplantation Programme, National Heart Centre, Singapore.

Introduction: The status of heart transplantation in Singapore is reviewed in this article.

Materials And Methods: The database of 40 consecutive heart transplantations from July 1990 through December 2007 is reviewed retrospectively. The data is compared with the 2008 registry data of the International Society for Heart and Lung Transplantation (ISHLT).

Results: The average age of recipients was 45.3 years. Ages ranged from 14 to 64 years. Ischaemic cardiomyopathy (52.5%) and dilated cardiomyopathy (42.5%) were the major indications. From 1990 to 1999, 50% of the donors sustained brain death from road traffic accident, 25% from cerebrovascular accident and 25% from falling from height, whereas the cause of brain death in the donors from 2000 to 2007 was 33%, 47% and 9.5%, respectively. The average donor age increased from 28.3 to 38.1 years. The significant morbidities in the recipients were hypertension, cytomegalovirus (CMV) infection, cardiac allograft vasculopathy and renal dysfunction. Thirtytwo required treatment for hypertension. 67.5% developed CMV disease requiring treatment. Cardiac allograft vasculopathy was diagnosed in 10. Rising creatinine levels reaching over 2.5 mg/dL was seen in 7. Three required renal dialysis. Epstein-Barr virus related lympho proliferative disorder occurred in 2 patients. One patient developed adenocarcinoma of stomach. The 30-day mortality was 10% and half life was 10 years. Cardiac allograft vasculopathy and sepsis caused 41.7% of mortality each. 11.7% of the mortality was due to cerebrovascular accident.

Conclusion: The status of heart transplantation in Singapore is comparable to the ISHLT registry data. Transplant provides excellent early survival of 80%; however, the expected half life is around 10 years after cardiac transplantation. The late mortality is mainly caused by cardiac allograft vasculopathy (CAV) and renal failure. More effort and research needs to be directed towards these issues to improve the long-term results.
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April 2009

Genetic polymorphisms in MDR1 and CYP3A4 genes in Asians and the influence of MDR1 haplotypes on cyclosporin disposition in heart transplant recipients.

Pharmacogenetics 2003 Feb;13(2):89-95

Laboratory of Clinical Pharmacology, Division of Clinical Trials and Epidemiological Sciences, National Cancer Centre, 11 Hospital Drive, Singapore 169610, Republic of Singapore.

Intestinal cytochrome P450 3A4 (CYP3A4) and P-glycoprotein (P-gp) both play a vital role in the metabolism of oral cyclosporine (CsA). We investigated the genetic polymorphisms in CYP3A4(promoter region and exons 5, 7 and 9) and MDR1 (exons 12, 21 and 26) genes and the impact of these polymorphisms on the pharmacokinetics of oral CsA in stable heart transplant patients (n = 14). CYP3A4 polymorphisms were rare in the Asian population and transplant patients. Haplotype analysis revealed 12 haplotypes in the Chinese, eight in the Malays and 10 in the Indians. T-T-T was the most common haplotype in all ethnic groups. The frequency of the homozygous mutant genotype at all three loci (TT-TT-TT) was highest in the Indians (31%) compared to 19% and 15% in the Chinese and Malays, respectively. In heart transplant patients, CsA exposure (AUC(0-4 h), AUC(0-12 h) and C(max)) was high in patients with the T-T-T haplotypes compared to those with C-G-C haplotypes. These findings suggest that haplotypes rather than genotypes influence CsA disposition in transplant patients.
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http://dx.doi.org/10.1097/00008571-200302000-00005DOI Listing
February 2003