Rajan Sharma
St George's, University of London
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Rajan Sharma.
Circulation | 2014
Sabiha Gati; Michael Papadakis; Nikolaos D. Papamichael; Abbas Zaidi; Nabeel Sheikh; Matthew Reed; Rajan Sharma; B. Thilaganathan; Sanjay Sharma
Background— Patients with heart failure and chronic anemia frequently demonstrate left ventricular (LV) trabeculations, which may be compatible with the diagnosis of LV noncompaction. We used the pregnancy model, which is characterized by a reversible increase in cardiac preload and other changes in cardiac function, to assess the development of de novo LV trabeculations in women with morphologically normal hearts. Methods and Results— One hundred two primigravida pregnant women were evaluated longitudinally with a series of echocardiograms in the first trimester, in the third trimester, and postpartum. Echocardiograms were analyzed according to established guidelines. Increased LV trabeculations and the presence of LV noncompaction were based on established criteria. Pregnancy was associated with an increased heart rate, stroke volume, and cardiac output, as well as increased LV volume and mass. During pregnancy, 26 women (25.4%) developed increased trabeculations. Eight women showed sufficient trabeculations to fulfill criteria for LV noncompaction. During the postpartum follow-up period of 24±3 months, 19 women (73%) demonstrated complete resolution of trabeculations, and 5 showed a marked reduction in the trabeculated layer. Conclusions— Pregnancy induces de novo LV trabeculations in a significant proportion of women. The results suggest that LV trabeculations occur in response to increased LV loading conditions or other physiological responses to pregnancy and are not specific for LV noncompaction. These factors should be considered in the assessment of individuals with LV trabeculations outside the context of symptoms of heart failure or familial cardiomyopathy.Background— Patients with heart failure and chronic anemia frequently demonstrate left ventricular (LV) trabeculations, which may be compatible with the diagnosis of LV noncompaction. We used the pregnancy model, which is characterized by a reversible increase in cardiac preload and other changes in cardiac function, to assess the development of de novo LV trabeculations in women with morphologically normal hearts.nnMethods and Results— One hundred two primigravida pregnant women were evaluated longitudinally with a series of echocardiograms in the first trimester, in the third trimester, and postpartum. Echocardiograms were analyzed according to established guidelines. Increased LV trabeculations and the presence of LV noncompaction were based on established criteria. Pregnancy was associated with an increased heart rate, stroke volume, and cardiac output, as well as increased LV volume and mass. During pregnancy, 26 women (25.4%) developed increased trabeculations. Eight women showed sufficient trabeculations to fulfill criteria for LV noncompaction. During the postpartum follow-up period of 24±3 months, 19 women (73%) demonstrated complete resolution of trabeculations, and 5 showed a marked reduction in the trabeculated layer.nnConclusions— Pregnancy induces de novo LV trabeculations in a significant proportion of women. The results suggest that LV trabeculations occur in response to increased LV loading conditions or other physiological responses to pregnancy and are not specific for LV noncompaction. These factors should be considered in the assessment of individuals with LV trabeculations outside the context of symptoms of heart failure or familial cardiomyopathy.nn# CLINICAL PERSPECTIVE {#article-title-24}
Circulation | 2013
Abbas Zaidi; Saqib Ghani; Rajan Sharma; David Oxborough; Vasileios F. Panoulas; Nabeel Sheikh; Sabiha Gati; Michael Papadakis; Sanjay Sharma
Background— Regular, intensive exercise results in physiological biventricular cardiac adaptation. Ethnicity is an established determinant of left ventricular remodeling; black athletes (BAs) exhibit more profound LV hypertrophy than white athletes (WAs). Right ventricular (RV) remodeling has not been characterized in BAs, although the issue is pertinent because BAs commonly exhibit ECG anomalies that resemble arrhythmogenic RV cardiomyopathy. Methods and Results— Between 2006 and 2012, 300 consecutive BAs (n=243 males) from 25 sporting disciplines were evaluated by use of ECG and echocardiography. Results were compared with 375 WAs and 153 sedentary control subjects (n=69 blacks). There were no ethnic differences between RV parameters in control subjects. Both BAs and WAs exhibited greater RV dimensions than control subjects. RV dimensions were marginally smaller in BAs than in WAs (proximal outflow tract, 30.9±5.5 versus 32.8±5.3 mm, P<0.001; longitudinal dimension, 86.6±9.5 versus 89.8±9.6 mm, P<0.001), although only 2.3% of variation was attributable to ethnicity. RV enlargement compatible with diagnostic criteria for arrhythmogenic RV cardiomyopathy was frequently observed (proximal outflow tract ≥32 mm; 45.0% of BAs, 58.5% of WAs). Anterior T-wave inversion was present in 14.3% of BAs versus 3.7% of WAs (P<0.001). Marked RV enlargement with concomitant anterior T-wave inversion was observed in 3.0% of BAs versus 0.3% of WAs (P=0.005). Further investigation did not diagnose arrhythmogenic RV cardiomyopathy in any athlete. Conclusions— Physiological RV enlargement is commonly observed in both black and white athletes. The impact of ethnicity is minimal, which obviates the need for race-specific RV reference values. However, in the context of frequent ECG repolarization anomalies in BAs, the potential for erroneous diagnosis of arrhythmogenic RV cardiomyopathy is considerably greater in this ethnic group.
European Heart Journal | 2013
Abbas Zaidi; Saqib Ghani; Nabeel Sheikh; Sabiha Gati; Rachel Bastiaenen; Brendan Madden; Michael Papadakis; Hariharan Raju; Matthew Reed; Rajan Sharma; Elijah R. Behr; Sanjay Sharma
AIMSnPre-participation cardiovascular screening of young athletes may prevent sports-related sudden cardiac deaths. Recognition of physiological electrocardiography (ECG) changes in healthy athletes has improved the specificity of screening while maintaining sensitivity for disease. The study objective was to determine the clinical significance of electrocardiographic right ventricular hypertrophy (RVH) in athletes.nnnMETHODS AND RESULTSnBetween 2010 and 2012, 868 subjects aged 14-35 years (68.8% male) were assessed using ECG and echocardiography (athletes; n = 627, sedentary controls; n = 241). Results were compared against patients with established right ventricular (RV) pathology (arrhythmogenic right ventricular cardiomyopathy, n = 68; pulmonary hypertension, n = 30). Sokolow-Lyon RVH (R[V1]+S[V5orV6] > 1.05 mV) was more prevalent in athletes than controls (11.8 vs. 6.2%, P = 0.017), although RV wall thickness (RVWT) was similar (4.0 ± 1.0 vs. 3.9 ± 0.9 mm, P = 0.18). Athletes exhibiting electrocardiographic RVH were predominantly male (95.9%), and demonstrated similar RV dimensions and function to athletes with normal electrocardiograms (RVWT; 4.0 ± 1.1 vs. 4.0 ± 0.9 mm, P = 0.95, RV basal dimension; 42.7 ± 5.2 vs. 42.1 ± 5.9 mm, P = 0.43, RV fractional area change; 40.6 ± 7.6 vs. 42.2 ± 8.1%, P = 0.14). Sensitivity and specificity of Sokolow-Lyon RVH for echocardiographic RVH (>5 mm) were 14.3 and 88.2%, respectively. Further evaluation including cardiac magnetic resonance imaging did not diagnose right ventricular pathology in any athlete. None of the cardiomyopathic or pulmonary hypertensive patients exhibited voltage RVH without additional ECG abnormalities.nnnCONCLUSIONnElectrocardiographic voltage criteria for RVH are frequently fulfilled in healthy athletes without underlying RV pathology, and should not prompt further evaluation if observed in isolation. Recognition of this phenomenon should reduce the burden of investigations after pre-participation ECG screening without compromising sensitivity for disease.
Journal of the American College of Cardiology | 2015
Abbas Zaidi; Nabeel Sheikh; Jesse K. Jongman; Sabiha Gati; Vasileios F. Panoulas; Gerald Carr-White; Michael Papadakis; Rajan Sharma; Elijah R. Behr; Sanjay Sharma
BACKGROUNDnPhysiological cardiac adaptation to regular exercise, including biventricular dilation and T-wave inversion (TWI), may create diagnostic overlap with arrhythmogenic right ventricular cardiomyopathy (ARVC).nnnOBJECTIVESnThe goal of this study was to assess the accuracy of diagnostic criteria for ARVC when applied to athletes exhibiting electrocardiographic TWI and to identify discriminators between physiology and disease.nnnMETHODSnThe study population consisted of athletes with TWI (n = 45), athletes without TWI (n = 35), and ARVC patients (n = 35). Subjects underwent electrocardiography (ECG), signal-averaged electrocardiography (SAECG), echocardiography, cardiac magnetic resonance imaging (CMRI), Holter monitoring, and exercise testing.nnnRESULTSnThere were no electrical, structural, or functional cardiac differences between athletes exhibiting TWI and athletes without TWI. When athletes were compared with ARVC patients, markers of physiological remodeling included early repolarization, biphasic TWI, voltage criteria for right ventricular (RV) or left ventricular hypertrophy, and symmetrical cardiac enlargement. Indicators of RV pathology included the following: syncope; Q waves or precordial QRS amplitudes <1.8 mV; 3 abnormal SAECG parameters; delayed gadolinium enhancement, RV ejection fraction ≤45%, or wall motion abnormalities at CMRI; >1,000 ventricular extrasystoles (or >500 non-RV outflow tract) per 24 h; and symptoms, ventricular tachyarrhythmias, or attenuated blood pressure response during exercise. Nonspecific parameters included the following: prolonged QRS terminal activation; ≤2 abnormal SAECG parameters; RV dilation without wall motion abnormalities; RV outflow tract ectopy; and exercise-induced T-wave pseudonormalization.nnnCONCLUSIONSnTWI and balanced biventricular dilation are likely to represent benign manifestations of training in asymptomatic athletes without relevant family history. Diagnostic criteria for ARVC are nonspecific in such individuals. Comprehensive testing using widely available techniques can effectively differentiate borderline cases.
European Journal of Vascular and Endovascular Surgery | 2013
Alan Karthikesalingam; Sandeep S. Bahia; B.O. Patterson; G. Peach; Alberto Vidal-Diez; Kausik K. Ray; Rajan Sharma; Robert J. Hinchliffe; Peter J. Holt; M.M. Thompson
OBJECTIVEnTo report the contemporary life expectancy of patients undergoing abdominal (AAA) or thoracic aortic aneurysm (TAA) repair in England, relative to a healthy control population.nnnMETHODSnA retrospective observational case-control study was carried out of Hospital Episode Statistics (HES) data, an administrative dataset covering the entire English National Health Service. Patients undergoing elective repair of an abdominal or thoracic aortic aneurysm in an English NHS hospital between April 2006 and March 2011 were included. Outcome measures were 5-year all-cause mortality (in- and out-of-hospital) and adverse cardiovascular events (myocardial infarction, stroke, emergency amputation or limb revascularisation).nnnRESULTSn19,505 AAA and 730 TAA repairs were identified, with 75,260 and 2,721 control participants, respectively, and 27.5 (1.0-60.0) months median (range) follow-up. Five-year survival was 67.4% for AAA against 81.1% for control participants, and 65.3% for TAA against 89.1% for control participants (p < .001). Freedom from adverse cardiovascular events was 86.1% for AAA against 93% for control participants and 89.1% for TAA against 94.4% for control participants (p < .001).nnnCONCLUSIONnLong-term survival remains poor after aneurysm repair and adverse cardiovascular events are common relative to the wider population. Further research is required to characterise and optimise cardiovascular risk prevention in patients with aortic aneurysms.
The Journal of Thoracic and Cardiovascular Surgery | 2017
Pouya Youssefi; Alberto Gómez; Taigang He; Lisa J. Anderson; Nick Bunce; Rajan Sharma; C. Alberto Figueroa; Marjan Jahangiri
Objectives: The complexity of aortic disease is not fully exposed by aortic dimensions alone, and morbidity or mortality can occur before intervention thresholds are met. Patient‐specific computational fluid dynamics (CFD) were used to assess the effect of different aortic valve morphologies on velocity profiles, flow patterns, helicity, wall shear stress (WSS), and oscillatory shear index (OSI) in the thoracic aorta. Methods: A total of 45 subjects were divided into 5 groups: volunteers, aortic regurgitation‐tricuspid aortic valve (AR‐TAV), aortic stenosis‐tricuspid aortic valve (AS‐TAV), aortic stenosis‐bicuspid aortic valve right‐left cusp fusion (BAV[RL]), and aortic stenosis‐right‐non cusp fusion (AS‐BAV[RN]). Subjects underwent magnetic resonance angiography, with phase‐contrast magnetic resonance imaging at the sino‐tubular junction to define patient‐specific inflow velocity profiles. Hemodynamic recordings were used alongside magnetic resonance imaging angiographic data to run patient‐specific CFD. Results: The BAV groups had larger mid‐ascending aorta diameters (P < .05). Ascending aorta flow was more eccentric in BAV (flow asymmetry = 78.9% ± 6.5% for AS‐BAV(RN), compared with 4.7% ± 2.1% for volunteers, P < .05). Helicity was greater in AS‐BAV(RL) (P < .05). Mean WSS was elevated in AS groups, greatest in AS‐BAV(RN) (37.1 ± 4.0 dyn/cm2, compared with 9.8 ± 5.4 for volunteers, P < .05). The greater curvature of the ascending aorta experienced highest WSS and lowest OSI in AS patients, most significant in AS‐BAV(RN) (P < .05). Conclusions: BAV displays eccentric flow with high helicity. The presence of AS, particularly in BAV‐RN, led to greater WSS and lower OSI in the greater curvature of the ascending aorta. Patient‐specific CFD provides noninvasive functional assessment of the thoracic aorta, and may enable development of a personalized approach to diagnosis and management of aortic disease beyond traditional guidelines.
Jacc-cardiovascular Imaging | 2017
Gherardo Finocchiaro; Harshil Dhutia; Andrew D’Silva; Aneil Malhotra; Alexandros Steriotis; Lynne Millar; Keerthi Prakash; Rajay Narain; Michael Papadakis; Rajan Sharma; Sanjay Sharma
OBJECTIVESnThis study sought to investigate the effect of different types of exercise on left ventricular (LV) geometry in a large group of female and male athletes.nnnBACKGROUNDnStudies assessing cardiac adaptation in female and male athletes indicate that female athletes reveal smaller increases in LV wall thickness and cavity size compared with male athletes. However, data on sex-specific changes in LV geometry in athletes are scarce.nnnMETHODSnA total of 1,083 healthy, elite, white athletes (41% female; mean age 21.8 ± 5.7 years) assessed with electrocardiogram and echocardiogram were considered. LV geometry was classified into 4 groups accordingxa0to relative wall thickness (RWT) and left ventricular mass (LVM) as per European and American Society of Echocardiography guidelines: normal (normal LVM/normal RWT), concentric hypertrophy (increased LVM/increased RWT), eccentric hypertrophy (increased LVM/normal RWT), and concentric remodeling (normalxa0LVM/increased RWT).nnnRESULTSnAthletes were engaged in 40 different sporting disciplines with similar participation rates with respect to the type of exercise between females and males. Females exhibited lower LVM (83 ± 17 g/m2 vs. 101 ± 21 g/m2; pxa0< 0.001) and RWT (0.35 ± 0.05 vs. 0.36 ± 0.05; pxa0< 0.001) compared with male athletes. Females also demonstrated lower absolute LV dimensions (49 ± 4 mm vs. 54 ± 5 mm; pxa0< 0.001) but following correction for body surface area, the indexed LV dimensions were greater in females (28.6 ± 2.7 mm/m2 vs. 27.2 ± 2.7 mm/m2; pxa0< 0.001). Most athletes showed normal LV geometry. A greater proportion of females competing in dynamic sport exhibited eccentric hypertrophy compared with males (22% vs. 14%; pxa0< 0.001). In this subgroup only 4% of females compared with 15% of males demonstrated concentric hypertrophy/remodeling (pxa0< 0.001).nnnCONCLUSIONSnHighly trained athletes generally show normal LV geometry; however, female athletes participating in dynamic sport often exhibit eccentric hypertrophy. Although concentric remodeling or hypertrophy in male athletes engaged in dynamic sport is relatively common, it is rare in female athletes and may be a marker of disease in a symptomatic athlete.
European Journal of Echocardiography | 2014
Dimitrios Poulikakos; Louise Ross; Alejandro Recio-Mayoral; Della Cole; Jocelyn Andoh; Nihil Chitalia; Rajan Sharma; Juan Carlos Kaski; Debasish Banerjee
UNLABELLEDnAim Mortality, predominantly due to cardiovascular events, is high in patients with chronic kidney disease (CKD) and left ventricular hypertrophy (LVH) is a strong risk factor. Vascular endothelial dysfunction (ED) is common in CKD, but its potential contribution to LVH in non-dialysis CKD is unknown. This study investigated the association of ED with LVH in non-dialysis CKD patients.nnnMETHODS AND RESULTSnWe studied 30 CKD patients (17 pre-dialysis and 13 renal transplant recipients) and 29 age-gender-matched controls. In both groups, high-sensitivity C-reactive protein (hsCRP) levels, systemic ED (brachial artery flow-mediated dilatation, FMD), and LVH using two-dimensional echocardiography were measured. LV mass index (LVMI) was calculated using Penn formula and indexed by height. CKD patients had higher CRP levels (3.9 ± 2.8 vs. 1.0 ± 0.7 mg/L; P < 0.001), reduced FMD (3.2 ± 2.1 vs. 6.1 ± 1.9%; P < 0.001), and increased LVMI (146.1 ± 40.2 vs. 105.3 ± 26.2 g/m; P < 0.001), compared with controls. In CKD patients, LVMI increased with decreasing FMD (r = -0.371; P = 0.043) and FMD decreased with increasing CRP (r = -0.741; P < 0.001). Patients with low FMD <2.3% had higher CRP and LVMI (161.9 ± 48.9 vs. 130.4 ± 20.7 g/m; P = 0.033), compared with CKD patients with FMD ≥2.3%. There was no significant difference in age, blood pressure, cholesterol, FMD, and LVMI between pre-dialysis and post-renal transplant CKD patients. In multivariate regression, the relationship between LVMI and FMD remained significant after adjusting for age, diabetes, and smoking (adjacent beta = -0.396; P = 0.004).nnnCONCLUSIONnThis pilot study demonstrates for the first time a relationship of ED with LVH in non-dialysis CKD patients; suggesting but not proving a cause-effect relationship.
British Medical Bulletin | 2017
Pouya Youssefi; Rajan Sharma; C. Alberto Figueroa; Marjan Jahangiri
IntroductionnTreatment guidelines for the thoracic aorta concentrate on size, yet acute aortic dissection or rupture can occur when aortic size is below intervention criteria. Functional imaging and computational techniques are a means of assessing haemodynamic parameters involved in aortic pathology.nnnSources of datanOriginal articles, reviews, international guidelines.nnnAreas of agreementnComputational fluid dynamics and 4D flow MRI allow non-invasive assessment of blood flow parameters and aortic wall biomechanics.nnnAreas of controversynAortic valve morphology (particularly bicuspid aortic valve) is associated with aneurysm of the ascending aorta, although the exact mechanism of aneurysm formation is not yet established.nnnGrowing pointsnHaemodynamic assessment of the thoracic aorta has highlighted parameters which are linked with both clinical outcome and protein changes in the aortic wall. Wall shear stress, flow displacement and helicity are elevated in patients with bicuspid aortic valve, particularly at locations of aneurysm formation.nnnAreas timely for developing researchnWith further validation, functional assessment of the aorta may help identify patients at risk of aortic complications, and introduce new haemodynamic indices into management guidelines.
BMJ Open | 2017
Anna Marciniak; Keli Glover; Rajan Sharma
Purpose The aim of this study was to evaluate the proportion of suspected heart failure patients with significant valvular heart disease. Early diagnosis of valve disease is essential as delay can limit treatment and negatively affect prognosis for undiagnosed patients. The prevalence of unsuspected valve disease in the community is uncertain. Participants We prospectively evaluated 79u2005043 patients, between 2001 and 2011, who were referred to a community open access echocardiography service for suspected heart failure. All patients underwent a standard transthoracic echocardiogram according to British Society of Echocardiography guidelines. Findings to date Of the total number, 29u2005682 patients (37.5%) were diagnosed with mild valve disease, 8983 patients (11.3%) had moderate valve disease and 2134 (2.7%) had severe valve disease. Of the total number of patients scanned, the prevalence of aortic stenosis, aortic regurgitation, mitral stenosis, mitral regurgitation was 10%, 8.4%, 1%, and 12.5% respectively. 18% had tricuspid regurgitation. 5% had disease involving one or more valves. Conclusions Of patients with suspected heart failure in the primary care setting, a significant proportion have important valvular heart disease. These patients are at high risk of future cardiac events and will require onward referral for further evaluation. We recommend that readily available community echocardiography services should be provided for general practitioners as this will result in early detection of valve disease.