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Featured researches published by Sushil Allen Luis.


Journal of The American Society of Echocardiography | 2014

Use of Three-Dimensional Speckle-Tracking Echocardiography for Quantitative Assessment of Global Left Ventricular Function: A Comparative Study to Three-Dimensional Echocardiography

Sushil Allen Luis; Akira Yamada; Bijoy K. Khandheria; V. Speranza; A. Benjamin; M. Ischenko; D. Platts; C. Hamilton-Craig; Luke J. Haseler; D. Burstow; Jonathan Chan

BACKGROUND The aim of this study was to determine whether global strains derived from three-dimensional (3D) speckle-tracking echocardiography (STE) are as accurate as left ventricular (LV) ejection fraction (LVEF) obtained by two-dimensional (2D) and 3D echocardiography in the quantification of LV function. METHODS Two-dimensional and 3D echocardiography and 2D and 3D STE were performed in 88 patients (LVEF range, 17%-79%). Two-dimensional and 3D global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain, and global area strain were quantified and correlated with LV function determined by 2D and 3D echocardiographic LVEF. Reproducibility, feasibility, and duration of study to perform 3D STE were assessed by independent, blinded observers. RESULTS A total of 78 patients (89%) underwent 3D STE. All 3D speckle-tracking echocardiographic parameters had strong correlations with assessment of LV function determined by 2D and 3D echocardiographic LVEF. Three-dimensional GCS was the best marker of LV function (r = -0.89, P < .0001). Subgroup analysis demonstrated that 3D speckle-tracking echocardiographic parameters were particularly useful in identifying LV dysfunction (LVEF < 50%). Receiver operating characteristic curve analysis demonstrated areas under the curve of 0.97 for 3D GCS, 0.96 for 3D global radial strain, 0.95 for 3D global area strain, and 0.87 for 3D GLS. An optimal 3D GCS cutoff value of magnitude < -12% predicted LV dysfunction (LVEF obtained by 2D echocardiography < 50%) with 92% sensitivity and 90% specificity. There was good correlation between 2D GLS and 3D GLS (r = 0.85, P < .001; mean difference, -1.7 ± 6.5%). Good intraobserver, interobserver, and test-retest agreements were seen with 3D STE. Time for image acquisition to postprocessing analysis was significantly reduced with 3D STE (3.7 ± 1.0 minutes) compared with 2D STE (4.6 ± 1.5 min) (P < .05). CONCLUSIONS Global strain by 3D STE is a promising novel alternative to quantitatively assess LV function. Three-dimensional STE is reproducible, feasible, and time efficient.


Journal of The American Society of Echocardiography | 2014

Reproducibility of Regional and Global Longitudinal Strains Derived from Two-Dimensional Speckle-Tracking and Doppler Tissue Imaging between Expert and Novice Readers during Quantitative Dobutamine Stress Echocardiography

Akira Yamada; Sushil Allen Luis; D. Sathianathan; Bijoy K. Khandheria; James Cafaro; C. Hamilton-Craig; D. Platts; Luke J. Haseler; D. Burstow; Jonathan Chan

BACKGROUND Longitudinal strain (LS) is a quantitative parameter that adds incremental value to wall motion analysis. The aim of this study was to compare the reproducibility of LS derived from Doppler tissue imaging and speckle-tracking between an expert and a novice strain reader during dobutamine stress echocardiography (DSE). METHODS Forty-one patients (mean age, 65 ± 15 years; mean ejection fraction, 58 ± 11%) underwent DSE per clinical protocol. Global LS derived from speckle-tracking and regional LS derived from both speckle-tracking and Doppler tissue imaging were measured twice by an expert strain reader and also measured twice by a novice strain reader. Intraobserver and interobserver analyses were performed using intraclass correlation coefficients (ICC), Bland-Altman analysis, and absolute difference values (mean ± SD). RESULTS Global LS measured by the expert strain reader demonstrated high intraobserver measurement reproducibility (rest: ICC = 0.95, absolute difference = 5.5 ± 4.9%; low dose: ICC = 0.96, absolute difference = 5.7 ± 3.7%; peak dose: ICC = 0.87, absolute difference = 11.4 ± 8.4%). Global LS measured by the novice strain reader also demonstrated high intraobserver reproducibility (rest: ICC = 0.97, absolute difference = 4.1 ± 3.4%; low dose: ICC = 0.94, absolute difference = 5.4 ± 5.9%; peak dose: ICC = 0.94, absolute difference = 6.1 ± 4.8%). Global LS also showed high interobserver agreement between the expert and novice readers at all stages of DSE (rest: ICC = 0.90, absolute difference = 8.5 ± 7.5%; low dose: ICC = 0.90, absolute difference = 8.9 ± 7.1%; peak dose: ICC = 0.87, absolute difference = 10.8 ± 8.4%). Of all parameters studied, LS derived from Doppler tissue imaging had relatively low interobserver and intraobserver agreement. CONCLUSIONS Global LS is highly reproducible during all stages of DSE. This variable is a potentially reliable and reproducible measure of myocardial deformation.


International Journal of Cardiology | 2014

Myocardial infarction secondary to 5-fluorouracil: Not an absolute contraindication to rechallenge?

Shruti Rateesh; Sushil Allen Luis; Chris R. Luis; Brett Hughes; Mugur Nicolae

5-fluorouracil (5-FU) is one of the most commonly prescribed che-motherapeutic agents for the treatment of a variety of malignancies.5-FUcardiotoxicityisuncommonbutpotentiallyserious:includingcar-diac arrhythmias, angina/myocardial infarction, ventricular dysfunction,cardiogenic shock, cardiac arrest, and sudden cardiac death [1].Anesti-mated 2–10% of patients exposed to 5-FU will develop cardiovascularcomplications; and patients with known ischaemic heart disease orprior myocardial infarction appear to be at higher risk [2].Proposedmechanismsunderlying5-FUcardiotoxicityincludedirectmyocardial toxicity, thrombogenic effects, immune phenomena andmyocardial ischaemia secondary to coronary artery vasospasm [3].Whilstrechallengewith5-FUisnotgenerallyrecommendedinpatientswith 5-FU cardiotoxicity due to concerns regarding recurrence anddeath: a careful assessment of the risks and benefits of such a rechal-lenge should be carefully conducted [3]. At present no consensus onprophylaxisortreatmentof5-FUcardiotoxicityexists,anddiscontinua-tion of 5-FU with the use of second-line agents is generally preferred.Adjuvant therapy with 5-FU containing chemotherapeutic regimensforms the basis of colon cancer therapy, carrying significant long termbenefits to both recurrence free and overall survival. These benefitsare not insignificant, with reductions in recurrence free and overallsurvival of 40% and 33% respectively, when compared to observationalone [4]. Furthermore, these benefits also remain superior to that ofalternativeagents,suchasRaltitrexed[5].Wedescribethefirstreportedcase of successful 5-FU rechallenge underclosecardiacobservation in apatient with 5-FU induced vasospastic myocardial infarction.A previously well 30 year old male with resected stage III (T4a,N2a) colorectal adenocarcinoma was commenced on 5-FU,leucovorin and oxaliplatin (FOLFOX 6) adjuvant chemotherapy(5- fluorouracil 400 mg/m


Heart Lung and Circulation | 2013

The safety profile of perflutren microsphere contrast echocardiography during rest and stress imaging: Results from an Australian multicentre cohort

D. Platts; Sushil Allen Luis; Damian Roper; D. Burstow; Tony Call; A. Forshaw; R. Pascoe

BACKGROUND Contrast enhanced echocardiography (CEE) is utilised when sub-optimal image quality results in non-diagnostic echocardiograms. However, there have been numerous safety notices issued by regulatory authorities regarding rare but potentially serious adverse reactions (AR). This multi-centre, retrospective analysis was performed to assess the short-term safety of CEE in a broad range of indications. METHODS All CEE performed over 58 months at three institutions were assessed for AR within 30 min. RESULTS A total of 5956 CEE were performed in 5576 patients. A total of 4903 were stress CEE and 1053 resting CCE. Bolus administration in 5719, infusion in 237 cases; 89.9% of CCE were outpatients. Commonest CEE indication was functional stress testing (82.3%). There were 16 AR related to CEE (0.27%). All AR were mild, transient and all patients made a full recovery. No cases of serious anaphylaxis or death within 30 min of contrast administration. Comparing those with and without an AR, there were no significant differences in age, gender, BMI, LVEF, patient location, exam type or RVSP. There was a slightly increased likelihood of an AR during infusion versus bolus dosing (p = 0.02). CONCLUSION CEE is a safe investigation in a broad range of indications and clinical scenarios. AR are very rare, mild and transient.


Best Practice & Research Clinical Endocrinology & Metabolism | 2016

Carcinoid heart disease: Diagnosis and management.

Sushil Allen Luis; Patricia A. Pellikka

Hedinger syndrome refers to carcinoid valvular heart disease. The disease is believed to be triggered by vasoactive substances that result in valvular fibrosis. It classically occurs in patients with metastatic carcinoid and preferentially involves the right sided cardiac valves. Affected valves become thickened and retracted, exhibiting regurgitation and sometimes, stenosis. Echocardiography is recommended in patients with carcinoid syndrome and a follow up study is advisable in those who develop a murmur or other symptoms or signs of valvular heart disease. For appropriately selected patients, valve replacement surgery appears to improve outcomes.


Circulation-cardiovascular Imaging | 2013

Massive Left Atrial Thrombus in a Patient With Rheumatic Mitral Stenosis and Atrial Fibrillation While Anticoagulated With Dabigatran

Sushil Allen Luis; K. Poon; Chris R. Luis; Akhil Shukla; Nicholas Bett; C. Hamilton-Craig

Dabigatran is an oral direct thrombin inhibitor licensed for use by the Food and Drug Administration.1,2 This novel anticoagulant is effective and approved for prevention of stroke and systemic embolism in nonvalvular atrial fibrillation (AF) and prevention of venous thromboembolism in adults receiving elective total hip or knee replacement surgery.1,2 These images present a cautionary account of failed dabigatran anticoagulation in a patient with valvular AF: an indication for which its use has not been approved. A 50-year-old female with severe rheumatic mitral stenosis underwent open mitral valvotomy under cardiopulmonary bypass 25 years prior. On subsequent annual surveillance, she remained asymptomatic and her mitral stenosis remained moderate on echocardiography with a mean transmitral gradient of 8 mm Hg. Permanent AF was previously diagnosed 12 months earlier, and she was commenced on warfarin and metoprolol. She had stable anticoagulation monitoring, no bleeding complications, and normal renal function, but was needle-phobic with psychological …


Cardiology Research and Practice | 2012

Non-Pharmacological Therapy for Atrial Fibrillation: Managing the Left Atrial Appendage

Sushil Allen Luis; Damian Roper; A. Incani; K. Poon; H. Haqqani; D. Walters

The prevalence of atrial fibrillation (AF) is increasing in parallel with an ageing population leading to increased morbidity and mortality. The most feared complication of AF is stroke, with the arrhythmia being responsible for up to 20% of all ischemic strokes. An important contributor to this increased risk of stroke is the left atrial appendage (LAA). A combination of the LAAs unique geometry and atrial fibrillation leads to low blood flow velocity and stasis, which are precursors to thrombus formation. It has been hypothesized for over half a century that excision of the LAA would lead to a reduction in the incidence of stroke. It has only been in the last 20–25 years that the knowledge and technology has been available to safely carry out such a procedure. We now have a number of viable techniques, both surgical and percutaneous, which will be covered in this paper.


Heart | 2017

Prevalence and predictors of intracranial aneurysms in patients with bicuspid aortic valve

Alexander C. Egbe; Ratnasari Padang; Robert D. Brown; Arooj R. Khan; Sushil Allen Luis; John Huston; Emmanuel Akintoye; Heidi M. Connolly

Objective To determine the prevalence and outcomes of intracranial aneurysm (IA) in patients with bicuspid aortic valve (BAV). Methods Retrospective review of patients with BAV who underwent brain MR angiography at the Mayo Clinic from 1994 to 2013. Results There were 678 patients included in this study—mean age 57±13 years, men 480 (71%), mean follow-up 10±3 years (5913 patient-years). Coarctation of aorta (COA) was present in 154 (23%) patients. There were 59 IAs identified in 52 of 678 patients (7.7%). IA was present in 20/154 patients (12.9%) with COA and 32/524 patients (5.7%) without COA (p<0.001). For the patients without COA, female gender and right–left cusp fusion were risks factors for IA in women after adjustment for all potential variables (HR 1.76, CI 1.31 to 2.68, p=0.03). There was no significant trend in the risk for IA across age tertiles: age ≤40 years versus 41–60 years (HR 1.19, p=0.34), and age 41–60 years versus 61–80 years (HR 1.06, p=0.56). Among the 52 patients with IA, enlargement occurred in three patients (6%), rupture in two patients (4%) and four patients (8%) underwent coil embolisation. For the 626 patients without IA at baseline, no patient developed IA over 7±2 years of imaging follow-up. Conclusions BAV is associated with a higher prevalence of IA compared to the general population, and this risk is higher in patients with COA, right–left cusp fusion and female gender.


Mayo Clinic Proceedings | 2017

CHA2DS2-VASc Score: A Predictor of Thromboembolic Events and Mortality in Patients With an Implantable Monitoring Device Without Atrial Fibrillation

Christine Parsons; Salma I. Patel; Stephen S. Cha; Win Kuang Shen; Santosh Desai; Alanna M. Chamberlain; Sushil Allen Luis; Maria I. Aguilar; Bart M. Demaerschalk; Farouk Mookadam; Fadi Shamoun

Objective: To determine if the CHA2DS2‐VASc score (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischemic attack, vascular disease, age 65–74 years, sex category) predicts thromboembolism and death in patients without atrial fibrillation in a population with implantable cardiac monitoring devices. Patients and Methods: A retrospective review utilizing the Rochester Epidemiology Project research infrastructure was conducted to evaluate the CHA2DS2‐VASc tool as a predictor of mortality and ischemic stroke, transient ischemic attack, or systemic embolism in patients without atrial fibrillation. An implantable device was required in the inclusion criteria to discern the absence of atrial fibrillation. The study period was January 1, 2004, through March 7, 2016. Results: The study population (N=1606) had a mean (SD) age of 69.8 (12.6) years and median follow‐up of 4.8 years (range, 0–12 years; quartile 1, 2.6 years and quartile 3, 8.1 years). The number of thromboembolic and mortality events stratified by CHA2DS2‐VASc score groupings of 0 to 2 (399 patients), 3 to 5 (756 patients), and 6 to 9 (451 patients) were 12 (3.0%), 109 (14.4%), and 123 (27.3%) and 22 (5.5%), 205 (27.1%), and 214 (47.4%), respectively. The CHA2DS2‐VASc score predicted thromboembolism and death. The hazard ratios (HRs) for thromboembolic events for CHA2DS2‐VASc scores 3 to 5 and 6 to 9 were 4.84 (95% CI, 2.66–8.80) and 10.53 (95% CI, 5.77–19.21) (reference group, scores 0–2). The HRs for death for the corresponding score categories were 4.45 (95% CI, 2.86–6.91) and 8.18 (95% CI, 5.23–12.78). The CHA2DS2‐VASc score also predicted development of atrial fibrillation, for which the HRs for scores 3 to 5 and 6 to 9 were 1.51 (95% CI, 1.13–2.00) and 2.17 (95% CI, 1.60–2.95). Conclusion: The CHA2DS2‐VASc tool predicts thromboembolic events and overall mortality in patients without atrial fibrillation who have implantable devices.


Circulation-cardiovascular Genetics | 2017

Previously Unreported in Women Galactosidase Alpha Pro409Ser Variant Is Associated with Fabry Disease

Sushil Allen Luis; Joseph J. Maleszewski; Phillip M. Young; Hartzell V. Schaff; Naveen L. Pereira

Fabry disease is a rare X-linked lysosomal storage disorder involving a deficiency in α- galactosidase A. This condition results in an impaired ability to metabolize globotriaosylceramide in the glycosphingolipid metabolic pathway, which accumulates within tissues throughout the body. Fabry disease affects 1 in 40 000 to 117 000 men with an unknown prevalence in women.1 Clinical presentations can be variable, ultimately resulting in potentially severe end-organ damage. In light of the variability in clinical presentation and rarity of the disease, initial misdiagnosis is common with a mean delay to diagnosis of between 13.7 and 16.3 years from symptom onset.1 Typical manifestations can include cutaneous lesions (angiokeratoma corporis), peripheral neuropathy, cerebrovascular accidents, proteinuria, renal insufficiency, and cardiac dysfunction.2,3 Cardiac manifestations include increased ventricular wall thickness, heart failure, valvular thickening and dysfunction, and coronary artery disease.2,3 Accurate and early diagnosis is imperative because early treatment with agalsidase β had been demonstrated to reduce the incidence of major adverse outcomes, including renal failure, stroke, cardiac events, and death.2 A 50-year-old woman presented to our institution with a recent onset of worsening exertional shortness of breath, fatigue, and chest tightness on a background of a presumptive diagnosis of hypertrophic cardiomyopathy made 10 years before. Her family history was significant for ischemic heart disease in her father and brother and valvular disease in her sister, but there was no known family history of hypertrophic cardiomyopathy. There were no other systemic symptoms, and clinical examination revealed a holosystolic murmur without other features of systemic disease, including cornea verticillata. Baseline renal function was normal with a creatinine of 0.8 mg/dL. Echocardiography (Figure 1A and 1B) demonstrated severe concentric increase in left ventricular wall thickness with systolic anterior motion of the mitral valve leaflets resulting in severe left ventricular outflow tract …

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D. Burstow

University of Queensland

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O. Raffel

University of Queensland

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Chris R. Luis

University of Queensland

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K. Poon

University of Queensland

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R. Slaughter

University of Queensland

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Akira Yamada

Tokyo Institute of Technology

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