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Featured researches published by Ahmed Vachiat.


Thrombosis Research | 2014

Prognostic Indicators for Recurrent Thrombotic Events in HIV-infected Patients with Acute Coronary Syndromes: Use of Registry Data From 12 sites in Europe, South Africa and the United States

Fabrizio D’Ascenzo; Enrico Cerrato; Darryn L. Appleton; Claudio Moretti; Andrea Calcagno; Nayef Abouzaki; George W. Vetrovec; Thibault Lhermusier; Didier Carrie; Barbara Das Neves; Javier Escaned; Salvatore Cassese; Adnan Kastrati; Alessandra Chinaglia; Riccardo Belli; Davide Capodanno; Corrado Tamburino; Francesca Santilli; Guido Parodi; Ahmed Vachiat; Pravin Manga; Luigi Vignali; Massimo Mancone; Gennaro Sardella; Francesco Fedele; James J. DiNicolantonio; Pierluigi Omedè; Stefano Bonora; Fiorenzo Gaita; Antonio Abbate

AIMS Limited data are available on prognostic indicators for HIV patients presenting with ACS. METHODS AND RESULTS Data on consecutive patients with HIV infection receiving standard highly active antiretroviral therapy (HAART) presenting with ACS between January 2001 and September 2012 were collected. Cardiac death and myocardial infarction (MI) were the primary end-points. 10,050 patients with ACS were screened, and among them a total of 201 patients (179 [89%] males and a median age of 53 [47-62] years) were included, 48% of them admitted for ST-elevation myocardial infarction and 14% having left ventricular systolic dysfunction (LVSD) at discharge. CD4+ counts less than 200 cells/mm(3) were reported in 18 patients (9%), and 136 patients (67%) were treated with nucleoside-reverse transcriptase inhibitors (NRTI). After a median of 24 months (10-41), 30 patients (15%) died, 12 (6%) for cardiac reasons, 20 (10%) suffered a MI, 29 (15%) a subsequent revascularization, and 7 (3%) a stent thrombosis. Other than LVSD (hazard ratio=6.4 [95% confidence interval [CI]: 1.6-26: p=0.009]), the only other independent predictor of cardiac death was not being treated with NRTI (hazard ratio=9.9 [95% CI: 2.1-46: p=0.03); a CD4 cell count <200 cells/mm(3) was the only predictor of MI (hazard ratio=5.9 [95% CI: 1.4-25: p=0.016]). CONCLUSIONS HIV patients presenting with ACS are at significantly increased risk for cardiac death if not treated with NRTI, and at significantly increased risk of MI if their CD4 cell count is <200 cells/mm(3), suggesting that the stage of HIV disease (and lack of NRTI treatment) may contribute to cardiovascular instability.


Journal of the American College of Cardiology | 2017

HIV and Ischemic Heart Disease

Ahmed Vachiat; Keir McCutcheon; Nqoba Tsabedze; Don Zachariah; Pravin Manga

The association of coronary heart disease (CHD) and human immunodeficiency virus (HIV) infection has been well recognized for many years. The etiology of the increased prevalence of CHD in HIV-infected populations is the result of complex interactions among the viral infection, host factors, traditional risk factors, and therapies for HIV. As the HIV population is living longer, largely attributable to combination antiretroviral therapy, there is concern about the effect of the rising prevalence of CHD on morbidity and mortality, as well its effect on health systems around the world. This review will highlight the epidemiological evidence linking HIV infection and CHD. It will also focus on our current understanding of the pathogenesis and factors associated with HIV infection and CHD. In addition, the review will highlight modes of presentation and management strategies for mitigating risk and treatment of HIV-positive patients presenting with CHD.


Ndt Plus | 2013

Renal failure in HIV-positive patients—a South African experience

Ahmed Vachiat; Eustasius Musenge; Shoyab Wadee; Saraladevi Naicker

Background Kidney disease is a major complication of HIV infection, with both acute kidney injury (AKI) and chronic kidney disease (CKD) contributing to morbidity and mortality. Incidence of AKI was reported as 5.9 per 100 patient years in ambulatory patients and ∼18% in hospitalized HIV-infected patients, an almost 3-fold higher risk compared with HIV uninfected patients in developed countries. CKD was reported in 6–48.5% of HIV-infected patients in Africa. There is a paucity of data regarding the prevalence and outcomes of AKI in HIV-infected patients in sub-Saharan Africa, the region most affected by HIV. Methods A retrospective review of 101 HIV-positive anti-retroviral therapy (ART)-naïve patients presenting with renal failure from 1 October 2005 to 30 September 2006 was undertaken. Results A total of 684 patients presented with renal failure, 101 (14.8%) of whom were HIV positive. Ninety-nine (98%) of HIV-positive patients were black and 56 (55%) were male, with mean age 38 ± 9.9 years (range 21–61 years). HIV-positive patients demonstrated severe immunosuppression, with mean CD4 count of 135 cells/µL (range 1–579 cells/µL). Fifty-seven (56%) HIV-positive patients presented with AKI, 21 (21%) with acute-on-chronic kidney disease and 23 (23%) with CKD; seven patients with AKI were excluded due to lack of records. The causes of AKI in the HIV-positive group included sepsis (60%), volume depletion and haemodynamic instability (19%), toxins (9%), urological obstruction (7%) and miscellaneous (14%). Forty-four per cent of HIV-positive and 47% of HIV-negative patients with AKI demised; P = 0.45. Hyponatraemia (P = 0.018), acidosis (P = 0.018), anaemia (P = 0.019) and hyperphosphataemia (P = 0.003) were predictors of mortality in HIV-positive patients with AKI. In comparison, predictors of mortality in the HIV-negative group were age (P = 0.023) and black ethnicity (P = 0.04). Conclusion HIV-positive patients, compared with the HIV-negative group, presented with AKI at a younger age and at an advanced stage of immunosuppression. Appropriate support, including dialysis, resulted in similar outcomes in both groups.


Cardiovascular Journal of Africa | 2016

Takotsubo cardiomyopathy post liver transplantation.

Ahmed Vachiat; Keir McCutcheon; Adam Mahomed; Gunter Schleicher; Liezl Brand; Jean F. Botha; Martin Sussman; Pravin Manga

Abstract A patient with end-stage liver disease developed stressinduced Takotsubo cardiomyopathy post liver transplantation, with haemodynamic instability requiring a left ventricular assist device. We discuss the diagnosis and management of this condition.


International Journal of Cardiology | 2017

Periprocedural myocardial infarction during percutaneous coronary intervention in an academic tertiary centre in Johannesburg

Nqoba Tsabedze; Keir McCutcheon; Lancelot Mkhwanazi; Riaz Garda; Ahmed Vachiat; Rohan Ramjee; Jameel Moosa; Themba Maluleke; Gloria Mukeshimana; Saffiyyah Karolia; Dineo Mpanya; Pravin Manga

BACKGROUND Percutaneous coronary intervention (PCI) is effective therapy for significant atherosclerotic coronary artery disease. Despite medical and technological advances in PCI, periprocedural myocardial infarction (PMI) remains a common complication. The frequency and factors associated with PMI have been well investigated in the developed world, yet there is a paucity of data from the developing world, especially Sub-Saharan Africa. METHODS We prospectively enrolled 153 adult patients undergoing PCI at the Charlotte Maxeke Johannesburg Academic Hospital from the 1st of February 2014 to 31st October 2014. Periprocedural Creatinine Kinase-MB and hs-Troponin I were routinely measured before PCI and at 16-24h post-procedure. The third universal definition of myocardial infarction was used to define a PMI event. RESULTS 152 participants met the inclusion criteria and were analysed for PMI. 70.4% participants were male. The mean age was 58.8 (SD 10.9) years old. Sixteen (10.5%) participants fulfilled the criteria for PMI. Side branch pinching with preserved TIMI III flow was noted in 62.5% of PMI cases. Duration of procedure (P=0.007), right coronary artery intervention (p=0.042) and total stent length (p=0.045) were independently associated with PMI. CONCLUSION PMI occurred in 10.5% of cases undergoing PCI. This is consistent with the prevalence of PMI internationally. Larger multicentre studies are required in our demographic region to further define relevant predictors and outcomes associated with PMI.


Clinical Nephrology | 2016

Volume overload and its risk factors in South African chronic kidney disease patients: an appraisal of bioimpedance spectroscopy and inferior vena cava measurements.

Muzamil Olamide Hassan; Raquel Duarte; Therese Dix-Peek; Ahmed Vachiat; Caroline Dickens; Sacha Grinter; Sagren Naidoo; Pravin Manga; Saraladevi Naicker

BACKGROUND Fluid retention occurs early in chronic kidney disease (CKD) resulting in increased cardiovascular morbidity and mortality. This study aimed to assess volume and nutritional status among South African CKD participants and determine the relationship between malnutrition, inflammation, atherosclerosis, and volume overload using a body composition monitor (BCM). We also evaluated the usefulness of BCM measurement in assessing volume overload. METHODS 160 participants comprising hemodialysis, peritoneal dialysis, stage 3 CKD patients, and healthy controls (40 in each group) were studied. A BCM was used to assess fluid and nutritional status. Cardiac dimension measurements, and inferior vena cava diameter (IVCD) and carotid intima media thickness were assessed by echocardiography and ultrasonography, respectively. Serum interleukin-6 (IL-6) and C-reactive protein (CRP) levels were measured as markers of inflammation. RESULTS Fluid overload and malnutrition were present in 68% and 63% of studied patients, respectively. Using physical examination findings as the reference measurements for volume overload, the area under the concentration curves for BCM and IVCD measurements were 0.866 (sensitivity 82%, specificity 74%, p < 0.001) and 0.727 (sensitivity 57%, specificity 70%, p < 0.001), respectively. Lean tissue index, inflammation, and atherosclerosis were associated with volume overload. CONCLUSIONS Volume overload and malnutrition were common across the spectrum of South African CKD cohorts; volume overload was associated with malnutrition, inflammation, and atherosclerosis. Bioimpedance spectroscopy (BIS) is a useful and sensitive tool for the assessment of fluid status in clinically euvolumic nondialytic CKD patients.


International Journal of Nephrology and Renovascular Disease | 2018

Atherosclerotic vascular disease and its correlates in stable black South African kidney transplant recipients

Stephen O. Oguntola; Muzamil Olamide Hassan; Raquel Duarte; Therese Dix-Peek; Caroline Dickens; Gbenga Olorunfemi; Ahmed Vachiat; Graham Paget; Pravin Manga; Saraladevi Naicker

Background Despite remarkable improvement in renal function attributable to kidney transplantation, the burden of cardiovascular disease (CVD) among kidney transplant recipients (KTRs) remains high in the post-transplant period. Aggressive use of statins in KTRs may make lipoprotein ratios correlate better with atherosclerotic vascular disease (AsVD) when compared with traditional lipid profile parameters. We therefore evaluated the clinical and echocardiographic correlates of AsVD among non-diabetic, stable, black KTRs in South Africa. Methods This was a cross-sectional study of 41 adult (18–65 years), non-diabetic, stable KTRs and 41 age- and sex-matched healthy controls. An interviewer-administered questionnaire was used to obtain information on participants’ sociodemographic and cardiovascular risk factors. Anthropometric parameters were measured. Urine and blood samples were obtained and analyzed. Echocardiography was performed and carotid intima media thickness (CIMT) was assessed in both right and left carotid arteries. Spearman’s rank correlation and binary logistic regression were performed to determine the relationship between CVD risk factors and AsVD. Results AsVD was present in 46.3% of KTRs compared to 17.1% of healthy controls (p = 0.004). Left ventricular hypertrophy was present in 92.7% of the KTRs. There were statistically significant differences in waist–hip ratio, systolic blood pressure, mean arterial pressure, urine albumin–creatinine ratio, serum fibrinogen, serum creatinine, estimated glomerular filtration rate, left atrial diameter, left ventricular mass (LVM), and left ventricular mass index (LVMI) between KTRs and controls. A positive relationship was seen between CIMT and certain risk factors for CVD including LVM, LVMI, and mitral valve deceleration time, (p < 0.001). Castelli index 2 and lipoprotein combine index (LCI) showed positive correlation with CIMT. On multivariate analysis, increasing age and kidney transplant status were independent predictors of AsVD after controlling for other risk factors. Conclusion AsVD was common among KTRs. Older age and kidney transplant status independently predicted AsVD. Castelli index 2 and LCI correlated with AsVD better than serum lipid parameters.


International Journal of Nephrology | 2018

Transforming Growth Factor-β Protects against Inflammation-Related Atherosclerosis in South African CKD Patients

Muzamil Olamide Hassan; Raquel Duarte; Therese Dix-Peek; Caroline Dickens; Sagren Naidoo; Ahmed Vachiat; Sacha Grinter; Pravin Manga; Saraladevi Naicker

Background Transforming growth factor-β (TGF-β) may inhibit the development of atherosclerosis. We evaluated serum levels of TGF-β isoforms concurrently with serum levels of endotoxin and various inflammatory markers. In addition, we determined if any association exists between polymorphisms in the TGF-β1 gene and atherosclerosis in South African CKD patients. Methods We studied 120 CKD patients and 40 healthy controls. Serum TGF-β1, TGF-β2, TGF-β3, endotoxin, and inflammatory markers were measured. Functional polymorphisms in the TGF-β1 genes were genotyped using a polymerase chain reaction-sequence specific primer method and carotid intima media thickness (CIMT) was assessed by B-mode ultrasonography. Results TGF-β isoforms levels were significantly lower in the patients with atherosclerosis compared to patients without atherosclerosis (p<0.001). Overall, TGF-β isoforms had inverse relationships with CIMT. TGF-β1 and TGF-β2 levels were significantly lower in patients with carotid plaque compared to those without carotid plaque [TGF-β1: 31.9 (17.2 – 42.2) versus 45.9 (35.4 – 58.1) ng/ml, p=0.016; and TGF-β2: 1.46 (1.30 – 1.57) versus 1.70 (1.50 – 1.87) ng/ml, p=0.013]. In multiple logistic regression, age, TGF-β2, and TGF-β3 were the only independent predictors of subclinical atherosclerosis in CKD patients [age: odds ratio (OR), 1.054; 95% confidence interval (CI): 1.003 – 1.109, p=0.039; TGF-β2: OR, 0.996; 95% CI: 0.994–0.999, p=0.018; TGF-β3: OR, 0.992; 95% CI: 0.985–0.999, p=0.029). TGF-β1 genotypes did not influence serum levels of TGF-β1 and no association was found between the TGF-β1 gene polymorphisms and atherosclerosis risk. Conclusion TGF-β isoforms seem to offer protection against the development of atherosclerosis among South African CKD patients.


Cardiology Clinics | 2018

A New Face of Cardiac Emergencies: Human Immunodeficiency Virus–Related Cardiac Disease

Nqoba Tsabedze; Ahmed Vachiat; Don Zachariah; Pravin Manga

The human immunodeficiency virus epidemic is a major health challenge of the twenty-first century as the transition from infectious complications to noncommunicable disease becomes more evident. These patients may present to the emergency department with a variety of cardiovascular diseases, such as acute coronary syndromes, heart failure, pericardial disease, infective endocarditis, venothromboembolism, and other conditions. Increased awareness is needed among health care professionals to enhance adequate identification and promote prompt management of these patients.


Journal of the American College of Cardiology | 2017

HIV and Nonischemic Heart Disease

Pravin Manga; Keir McCutcheon; Nqoba Tsabedze; Ahmed Vachiat; Don Zachariah

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Pravin Manga

University of the Witwatersrand

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Keir McCutcheon

University of the Witwatersrand

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Nqoba Tsabedze

University of the Witwatersrand

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Saraladevi Naicker

University of the Witwatersrand

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Caroline Dickens

University of the Witwatersrand

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Raquel Duarte

University of the Witwatersrand

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Therese Dix-Peek

University of the Witwatersrand

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Don Zachariah

University of the Witwatersrand

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Sacha Grinter

University of the Witwatersrand

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Sagren Naidoo

University of the Witwatersrand

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