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BOARD CERTIFICATIONS:

• Cardiovascular Disease
• Nuclear Cardiology
• Echocardiography
• Cardiac CT (pending)

LANGUAGES:

• English
• Hindi
• Punjabi

HOSPITALS:

• Baylor Scott & White Heart and Vascular Hospital - Dallas
• Baylor University Medical Center
• Hunt Regional Medical Center
• Texas Health Rockwall

EDUCATION:

• MBA, Graduated with Honors: University of Texas at Dallas Naveen Jindal School of Business, Dallas, TX
• Fellowship, Heart Failure/Transplant Hospitalist: Division of Cardiology, University of Washington Medical Center, Seattle, WA
• Fellowship, Cardiovascular Medicine: SUNY, Buffalo, NY
• Residency, Internal Medicine: University of Washington Medical Center, Seattle, WA
• Internship, Internal Medicine: University of Washington Medical Center, Seattle, WA
• Medical School, MD Degree: University of Washington School of Medicine, Seattle, WA
• Undergraduate: Bachelor of Science in Biology, with Honors, University of Puget Sound, Tacoma, WA

PROFESSIONAL APPOINTMENTS:

• Member: Quality and Safe Committee - Baylor Heart and Vascular Hospital (2014-present)
• Director: Hunt Regional Hospital Cardiac Cath Lab (2012-2014)
• Partner: Cardiology Consultants of Texas, Dallas, TX (2014-present)
• Member: Quality Assurance Committee - Buffalo Medical Group (2010-2012)
• Assistant Professor: University of Rochester Medical Center (2008-2011)

HONORS/AWARDS:

• Chief Cardiology Fellow - SUNY Buffalo Cardiology Fellowship (2006-2007)
• Nominated for Best Resident Teacher Award by medical students as residents (2002)
• Elected UW Alumni Representative for class 2001 - University of Washington School of Medicine (2001)
• Klea Bartirakas Award - Western Regional Medical Student Research Forum, Carmel, CA, Best Oral Presentation out of over 400 medical students from all over North America (2000)
• Best Oral Research Presentation, National Student Research Forum, Galveston, TX - In Epidemiology and Infectious Diseases for AIDS project in North India (1999)
• Elected Medical Student Association (MSA) Class Secretary (1999)

PROCEDURES:

• EKG
• Echocardiography
• Nuclear Stress Testing
• Arterial & Venous Extremity Dopplers / ABIs
• Arrhythmia Monitoring
• Coronary Calcium Scoring & Coronary CTA
• Cardiac MRI & MRI

SERVICES:

• Chest Pain
• Atrial Fibrillation
• Hypertension
• Congestive Heart Failure
• Peripheral Arterial Disease
• Stress Testing
• Coronary Artery Disease
• Weight Loss

Schedule Appointment with Dr. Thamwiwat:

• Bedford Clinic
• Huguley Clinic
• Southlake Clinic

BOARD CERTIFICATIONS:

• Interventional Cardiology
• Cardiovascular Disease
• Echocardiography
• Nuclear Cardiology
• Internal Medicine

HOSPITALS:

• Glen Rose Medical Center
• Medfinity Health HEB
• Texas Health HEB
• Texas Health Huguley Hospital Fort Worth South

EDUCATION:

• Fellowship, Interventional Cardiology: Baylor College of Medicine, Houston, Texas
• Fellowship, Cardiovascular Disease: Baylor College of Medicine, Houston, Texas 
• Residency, Internal Medicine:  Baylor College of Medicine, Houston, Texas 
• Medical School, MD Degree: Texas Tech University Health Sciences Center School of Medicine, Lubbock, Texas
• Undergraduate: The University of Texas at Arlington, Arlington, Texas 

PROFESSIONAL ASSOCIATIONS:

• Alpha Omega Alpha Honor Medical Society
• American College of Cardiology
• American Medical Association

HONORS/AWARDS:

• Ambulatory Care Achievement Award, Baylor College of Medicine (June 2014)
• Outstanding Student Award, Department of Internal Medicine, Texas Tech School of Medicine (2011)
• Alpha Omega Alpha Honor Medical Society (2010-present)
• University Scholar Award (2005-2006, 2006-2007)
• Honoree for College of Science Academic Excellence Reception (2003)
• The National Dean's List (2002-2007)

PUBLICATIONS/MEDIA:

• Thamwiwat, A, Sudhakar D, Paniagua D, and Denktas AE. Suspected coronary fat embolism after liposuction. Catheter Cardiovasc Interv. 2018;1-4.

• Thamwiwat A, Levine GN. Chapter 14: Chest pains and Angina. Cardiology Secrets, 5th Edition. Ed. Glenn N. Levine. Philadelphia: Elsevier, 2018.125-134. Print.

• Thamwiwat A, Mejia R, Nutman TB, Bates JT. (2014). Strongyloidiasis as a cause of chronic diarrhea, identified using next-generation Strongyloides stercoralis-specific immunoassays. Curr Trop Med Rep. 2014; 1:145-147.

• Hira RS, Thamwiwat A, Kar B. Tandem. Heart placement for cardiogenic shock in acute severe mitral regurgitation and right ventricular failure. Catheter Cardiovascular Interv. 2014;82(2):319-322.

BOARD CERTIFICATIONS:

• Interventional Cardiology
• Cardiovascular Disease
• Nuclear Cardiology
• Echocardiography
• Internal Medicine

HOSPITALS:

• Baylor Scott & White Medical Center - Lake Pointe
• Baylor Scott & White Medical Center - Plano
• Baylor Scott & White | The Heart Hospital - Denton
• Baylor Scott & White | The Heart Hospital - Plano
• Methodist Richardson Medical Center

EDUCATION:

• Fellowship, Interventional Cardiology:  Saint Vincent’s Hospital and Medical Centers, NY
• Fellowship, Cardiovascular Disease:  Saint Vincent’s Hospital and Medical Centers, NY
• Residency, Internal Medicine: Albert Einstein College of Medicine/Montefiore Medical Center, NY
• Medical School, MD Degree:  SUNY Stonybrook School of Medicine, NY
• Undergraduate, BS Degree:  CUNY City College, NY

HONORS/AWARDS:

• Saint Vincent’s Hospital and Medical Centers, New York (2007-2008)
• Saint Vincent’s Hospital and Medical Centers, New York (2004-2007)
• Albert Einstein College of Medicine/Montefiore Medical Center, New York (2001-2004)
• SUNY Stonybrook School of Medicine, New York (1994-2001)
• CUNY City College, New York (1994-2001)

PROFESSIONAL APPOINTMENTS:

• Medical Executive Committee, Member - Baylor Scott and White Medical Center at Garland, Texas (2012-2018)
• American Heart Association/Fellows Society of Greater New York, Fellow Liaison – St. Vincent's Hospital, NY (2005-2006)

PROFESSIONAL ASSOCIATIONS:

• The Society of Cardiovascular Angiography and Interventions, SCAI-Member (2007-present)
• North American Society of Cardiovascular Imaging, NASCI-Member (2006-present)
• American Society of Echocardiography, ASE-Member (2004-present)
• American Society of Nuclear Cardiology, ASNC-Affiliate Member (2004-present)
• American College of Cardiology, ACC-Member (2004-present)
• American Heart Association, AHA-Member (2004-present)
• American Medical Association, AMA-Member (2001-present)

PUBLICATIONS:

Research:

• Co-Investigator, "Vascular Supply of the Anterobasal Segment of the Left Ventricle, Retrospective review of 45 consecutive coronary angiography cases looking at the Anterobasal Segment contractility along with patency of the native Left Anterior Descending Artery and Left Internal Mammary Artery." (2005-2006)
• Co-Investigator, Worked with Dr.Thierry LeJemtel on the Brain Natriuretic Peptide (BNP) study. The purpose of the project was to determine if BNP levels could be used to determine the cardiovascular status of patients with Congestive Heart Failure (2002)

​

Presentations:

• Presentation: Pre-Op Clearance to the Anesthesia department at St.Vincent's Hospital and Medical Center. (2006)
• Electrocardiogram Interpretation for medical students and house staff at St. Vincent's Hospital and Medical Center/New York Medical College. (2004-2006)
• Over 100 presentations through out fellowship in case management conferences, cardiac catheterization conferences, M & M and cardiac surgical conferences, Journal club conferences, Cardiac Critical Care conferences, EP, Echo, EKG, CHF and Nuclear conferences

Schedule Appointment with Dr. Moustapha:

• Bedford Clinic
  
• Southlake Clinic

BOARD CERTIFICATIONS:

• Interventional Cardiology
• Cardiovascular Disease
• Nuclear Medicine

LANGUAGES:

• English
• Arabic
• French

HOSPITALS:

• Glen Rose Medical Center
• Medfinity Health HEB
• Texas Health Heart & Vascular Hospital Arlington
• Texas Health HEB

EDUCATION:

• Fellowship, Interventional Cardiology: University of Texas at Houston, Houston, TX 
• Fellowship, Cardiovascular Disease: University of Texas at Houston, Houston, TX 
• Residency, Internal Medicine: Cleveland Clinic Foundation, Cleveland, OH
• Internship, Internal Medicine: Cleveland Clinic Foundation, Cleveland, OH
• Medical School, MD Degree: American University of Beirut, New York, NY 

PROFESSIONAL ASSOCIATIONS:

• Fellow of the American College of Cardiology

Schedule Appointment with Dr. Rashdan:

• Bedford Clinic
  
• Southlake Clinic

BOARD CERTIFICATIONS:

• Interventional Cardiology
• Cardiovascular Disease
• Echocardiography
• Internal Medicine

LANGUAGES:

• English
• Arabic
• French

HOSPITALS:

• Glen Rose Medical Center
• ​Medfinity Health HEB
• Texas Health HEB
• Texas Health Heart & Vascular Hospital Arlington

EDUCATION:

• Fellowship, Interventional Cardiology: University of Oklahoma, Oklahoma City, OK 
• Fellowship, Cardiovascular Disease: University of Oklahoma, Oklahoma City, OK 
• Fellowship, Echocardiology: Institut de Cardiologie de Montreal, Montreal, Quebec, Canada 
• Fellowship, Interventional Cardiology: Institut de Cardiologie de Montreal, Montreal, Quebec, Canada 
• Residency, Internal Medicine:  University of Pennsylvania, Philadelphia, PA 
• Internship, Internal Medicine:  University of Pennsylvania, Philadelphia, PA
• Internship, Internal Medicine:  Pitie-Salpetriere Medical School 
• Internship, Internal Medicine:  Dreux General Hospital 
• Medical School, MD Degree: Damascus University School of Medicine, Lebanon

BOARD CERTIFICATIONS:

• Interventional Cardiology
• General Cardiology

HOSPITALS:

• Medical City Plano
• Texas Health Allen
• Texas Health Frisco
• Texas Health Plano

EDUCATION:

• Fellowship, Interventional Cardiology: Baylor College of Medicine, Houston, TX
• Fellowship, Cardiovascular Disease: Baylor College of Medicine, Houston, TX
• Residency, Internal Medicine:  Baylor College of Medicine, Houston, TX
• Medical School, MD Degree:  Medical College of Virginia, Virginia Commonwealth, Richmond, Virginia 
• Graduate School, Masters of Science in Physiology Degree:  Medical College of Virginia, Virginia Commonwealth, Richmond, Virginia
• Undergraduate, Bachelors of Science in Biology Degree (Departmental Honors): Mary Washington College, Fredericksburg, Virginia 

PROCEDURAL SKILLS:

• Complex Coronary & Peripheral Interventions
• Heart Catheterizations
• Percutaneous Support Devices (Impella, IABP)
• Venous Reflux Disease & Ablation Therapy
• TAVR

PUBLICATIONS/MEDIA:

Publications:

• Brown WR, Levine, G. “Chest Pains and Angina”. In Levine, G, Cardiology Secrets (4th , pp. 110-116). Philadelphia, PA: Elsevier Saunders. (2014).

• Salloum FN, Abbate A, Houser J, Mudrick C, Roy S, Brown WR, Qureshi I, Prabhakar S and Kukreja R. “Sildenafil (Viagra) Attenuates Ischemic Cardiomyopathy and Improves Left Ventricular Function in Mice”. Am J Physiol Heart Circ Physiol. 2008 Mar;294(3):H1398-406. Epub. Jan 25, 2008.

• Majid M, Brown WR, Divakaran V, Virani S. “Pulmonic Valve Endocarditis, A Case Report.” Submitted to Texas Heart Inst Journal.

• Divakaran VG, Brown WR, Virani S. “Images in Echocardiography: A Freely Floating Saphenous Vein Graft.” Echocardiography. Vol 26. Aug, 2009.

• Brown WR. Assisted Drs. R. Kukreja and F. Salloum in the investigation of PDE-5 inhibitors and their role in cardio protection. “Chronic Inhibition of PDE-5 with Sildenafil (Viagra) Attenuates Ischemic Cardiomyopathy and Improves Left Ventricular Function in Mice”. 2007.

• Brown WR. Worked with Dr. T. Duane (Trauma Surgery) in the Medical College of Virginia Emergency Department. This research considered the value of pelvic/cervical spine films, and outcomes in various patient populations, including the obese and the diabetic patient. “The Role and Influence of Plain Films and Patient Demographics on Outcomes in the Trauma Bay." 2006.

• Brown WR. Worked with Dr. J. Feher to complete a thesis in physiology research. “Continuous Chemiluminescent Measurement of Superoxide in Intact Rat Hearts During Ischemia-Reperfusion.” 2002-2003.

• Brown WR. As a candidate for Biology departmental honors, worked with Dr. K. Loesser to complete a thesis in biological research. In May of 2001, presented research to the Virginia Academy of Science. The work subsequently appeared in the Academy’s publication. “Vitamin E: Efficacy of Gamma-Tocopherol vs. Alpha-Tocopherol in Atherosclerosis Prevention.” 2000-2001.

Poster Presentations:

• Oliver PA, Brown WR, Regan C, Stoltzfus J, Ornato JP. “Correlation Between Heart Rate in Pre-Hospital Patients In Atrial Fibrillation With Rapid Ventricular Response And Blood Serum Magnesium Levels”. AAEM meeting, Las Vegas, NV. Feb 2010.

• Salloum F, Abbate A, Brown WR, Hoke N, Kukreja RC. “Phosphodiesterase Inhibitors Reduce Myocardial Infarction, Apoptosis and Improve Post Ischemic Ventricular Function in Female Mice”. ACC meeting, Chicago, IL. March, 2008.

Dr. Asher Imam, D.O., F.A.A.N., is an experienced neurologist and neurophysiologist, specializing in neurology, clinical neurophysiology, vascular neurology, and sleep medicine. He is also the president and founder of Southlake Neurology & Sleep Wellness Clinic in Southlake, Texas. 

At Southlake Neurology & Neurophysiology Clinic, Dr. Imam focuses on the diagnosis and treatment of acute and chronic neurological disorders, including epilepsy, multiple sclerosis, sleep disorders, and chronic headaches. He also served as the director of Baylor-Grapevine Comprehensive Epilepsy and Sleep Disorders Center in Grapevine, Texas. There, Dr. Imam treated patients with sleep and epileptic disorders while maintaining the integrity of the program by educating staff technicians and their certifications. He also served as a director of neurosciences at Baylor Scott and White Medical Center in Grapevine, Texas for 9 years where he started the stroke program. Dr. Imam also started the first stroke certified (Joint Commission) in Tarrant County at Medical Center of Arlington. He has been recognized as a Top Doctor by Fort Worth magazine and has received several awards for his compassionate approach to care and his dedication to patient satisfaction. Dr. Imam is a clinical adjunct professor of neurosciences at TCU-UNTHSC School of Medicine. 

Certifications:

• Diplomate in the specialty of Neurology

• Diplomate in the subspecialty of Clinical Neurophysiology

• Diplomate in the subspecialty of Vascular Neurology

• Diplomate in the subspecialty of Sleep Medicine

Education:

• Fellowship in Clinical Neurophysiology (neuromuscular disorders and epilepsy) from

• Medical College of Georgia; Augusta, Georgia

• Residency in neurology from Medical College of Georgia; Augusta, Georgia

• Internal medicine internship from Medical College of Georgia; Augusta, Georgia

• Doctor of Osteopathic Medicine from University of North Texas health science Center at Fort Worth, Texas

• Bachelor of Science in Electrical Engineering from Lamar University Beaumont, Texas

Years of experience:

•Over 20 years of both inpatient and outpatient experience treating a wide variety of neurological disorders.

•Awarded Fellowship of American Academy of Neurology (FAAN) in 2022.

Previous leadership positions:

• Director of Baylor-Grapevine Comprehensive Epilepsy and Sleep Disorders Center

• Director of Baylor-Grapevine Stroke Center of Excellence

• Director of Stroke Program at Medical Center of Arlington

Awards:

• Living Magazine’s Best of North Texas 2020 and 2021

• Top Neurologist 2019

• Best of Physicians and Surgeons for 11 years in Southlake, Texas (2018)

• America’s Most Honored Profession 2018

• Patients’ Choice Award (Vitals) 2018

• Top Docs Texas Monthly 2015, 2018, 2019

• Super Docs (Tarrant County Addition) March 2014

• People’s Choice Award for Patient Satisfaction

• Physician of the month, July 2011, Baylor Scott and White Medical Center 

• Featured on ABC, CBS and NBC prime-time news

• Top Docs of Fort Worth Texas, 2009

• Alpha Epsilon Delta and Phi Beta Pi Honor societies

• AMA/MSS Outstanding membership recruitment award

• AMA/MSS Outstanding Student Sponsored Activity/Service

• President, American Medical Association/MSS UNTHSC chapter

• Delegate, American Medical Association/MSS

• Delegate, Texas Medical Association/MSS

• Student Representative, Tarrant County Medical Society

• Who’s who in Science and Engineering

• Who’s who in Professionals and Executives

Suchitra Kaminen, MD, provides exceptional, cutting-edge care to a diverse group of patients at her North Dallas Primary Care Doctors office in Frisco, Texas. Certified by the American Board of Internal Medicine in both internal medicine and hospice and palliative medicine, she combines her expertise and extensive experience to help patients achieve their healthiest, most fulfilling lives.

Dr. Kamineni earned her medical degree from Kakatiya Medical College in Warangal, India. She then completed an internal medicine residency at Sinai-Grace Hospital—Detroit Medical Center in Michigan. She further specialized by completing a fellowship in hospice and palliative medicine at the University of Texas Health Science Center at Houston.

Dr. Kamineni utilizes her comprehensive training to deliver personalized care to each patient in her community. Her wide range of health services includes osteoporosis screenings, EKGs, Pap smears, preventive cancer screenings, and treatment for both common and complex conditions, such as hypertension, diabetes, high cholesterol, thyroid disorders, and asthma. Additionally, she offers annual wellness exams.

She is an active member of the American College of Physicians and the Indian Medical Association. Certified by the American Board of Internal Medicine in both internal medicine and hospice and palliative medicine, she combines her expertise and extensive experience to help patients achieve their healthiest, most fulfilling lives.

To schedule an appointment with Dr. Kaminen and the team at North Dallas Primary Care Doctors, call the office or request an appointment online today.

Bishwas Upadhyay, MD, is a board-certified internal medicine physician at Texas Primary & Pediatric Care in Irving, Texas. Dr. Upadhyay’s philosophy in medicine is to help the body care for itself. He strongly believes in the power of preventive medicine and places high importance on the doctor-patient relationship. He is known for being attentive and articulate, and finds joy in educating and counseling his patients. 

Dr. Upadhyay is originally from the Himalayan country of Nepal. He graduated from Nepalgunj Medical College in Nepal and completed his residency training in internal medicine at Presence Saint Joseph Hospital in Chicago, Illinois, where he served as a chief resident. Afterward, he joined the University of Nevada Reno School of Medicine as an assistant professor of medicine and later served as an academic hospitalist and associate program director for their internal medicine residency program. 

In addition to taking care of his patients in the hospital, Dr. Upadhyay also taught medical students and residents in both hospital and primary care settings. During his tenure as the associate program director at the University of Nevada, he developed a quality improvement and patient safety curriculum. He also coached and mentored residents in their quality improvement and patient safety projects. 

In addition to his board-certification, Dr. Upadhyay is a fellow of the American College of Physicians and received several awards and recognitions throughout his medical career. Dr. Upadhyay is fluent in English, Nepali, Hindi, and Urdu, allowing him to better serve the diverse patient populations in his community.

Outside of work, Dr. Upadhyay loves hiking, spending time with his family, and traveling. He is also an amateur cook.

Munir Hazbun, MD, is a board-certified pulmonologist, critical care specialist, and sleep medicine physician serving patients in Dallas, Texas. He joined Southwest Pulmonary Associates in 2008 and brings a wealth of experience and a patient-centered approach to the diagnosis and treatment of complex respiratory and sleep disorders.

Originally from Santiago, Chile, Dr. Hazbun earned his medical degree from the prestigious Universidad de Chile. He completed his internship at Texas Tech Health Science Center in El Paso and went on to pursue fellowship training at Baylor College of Medicine in Houston, where he specialized in Pulmonary, Critical Care, and Sleep Medicine.

Dr. Hazbun is quadruple board certified by the American Board of Internal Medicine in Pulmonary Medicine, Sleep Medicine, and Internal Medicine. His clinical interests include persistent cough, shortness of breath, lung cancer, sarcoidosis, and complex sleep-related breathing disorders. Known for his thoughtful, comprehensive care, he works closely with each patient to identify the root cause of their symptoms and create personalized treatment plans.

Fluent in both English and Spanish, Dr. Hazbun is committed to serving the diverse needs of the Dallas community. He has been named among D Magazine's Best Doctors and recognized as a Texas Super Doctor from 2010 to 2015 and again in 2025. He has also served as a board member for the local chapter of the American Lung Association.

Outside of medicine, Dr. Hazbun enjoys spending time with his wife, Dr. Pilar Bescos, a family medicine physician, and their two children. His personal interests include biking, pickleball, golf, learning piano, gardening and traveling with his family.

Arhaanth Reddy, MD, is a board-certified pulmonologist at Southwest Pulmonary Associates in Plano, Texas. He is known for his expertise in diagnosing and treating complex respiratory conditions and for delivering evidence-based care with compassion and precision.

Dr. Reddy earned his medical degree from the University of California, San Diego School of Medicine, and completed his residency in internal medicine at UT Southwestern Medical School in Dallas, Texas. He went on to complete a fellowship in pulmonary and critical care medicine at UT Southwestern, where he also earned a Master of Science in Healthcare Leadership and Management. His academic excellence was recognized early on with election to the Alpha Omega Alpha Honor Medical Society and the prestigious Richard Mays Smith Award in Internal Medicine.

Dr. Reddy is triple board-certified by the American Board of Internal Medicine in Critical Care Medicine, Neurocritical Care Medicine, and Pulmonary Medicine.

In addition to his clinical work, Dr. Reddy serves as the current Vice Chair of the Department of Medicine at Texas Health Plano, where he helps shape the future of patient care, quality, and medical education.

Dr. Reddy offers a comprehensive range of advanced diagnostic procedures, including robotic bronchoscopy, endobronchial ultrasound (EBUS), and integrated 3D fluoroscopy, providing patients with cutting-edge evaluation and treatment options.

He has also been the recipient of several awards, including the:

• Alpha Omega Alpha Honor Medical Society, 2011
• Richard Mays Smith Award in Internal Medicine, UT Southwestern, 2011

Dr. Reddy chose a career in pulmonary and critical care medicine because he enjoys complex problem-solving and transforming insights into better outcomes for his patients.

Outside of medicine, he enjoys traveling, photography, reading, and, most of all, spending time with his three wonderful children.

Ross Schumacher, MD, is one of the skilled pulmonologists practicing at the Southwest Pulmonary Associates location in Plano, Texas. He is a versatile and compassionate pulmonary physician who joined Southwest Pulmonary Associates in 2023. His medical journey encompasses intensive care expertise and long-term patient relationships.

Dr. Schumacher completed his undergraduate studies at Indiana University in Bloomington, Indiana. He then went on to complete his Doctor of Medicine at the Indiana University School of Medicine in Indianapolis. He completed his fellowship at the University of Alabama at Birmingham (UAB) and his residency at the University of Texas-Southwestern. He earned the Critical Care Fellow of the Year at UAB in 2022 and the House Officer of Excellence at UT Southwestern in 2019. 

Dr. Schumacher is board-certified in Internal Medicine, Critical Care Medicine, and Pulmonary Medicine by the American Board of Internal Medicine. He has also been a member of CHEST and the American Thoracic Society (ATS) since 2020. Additionally, Dr. Schumacher is an advanced bronchoscopist with a focus on the robotic sampling of micronodules. 

Outside of medicine, Dr. Schumacher finds joy in his family—married to Victoria in 2020, welcomed son Dean Wilder in 2021—and a loyal dog named Hoosier. Dr. Schumacher's interests span from Kurt Vonnegut's literature to Immanuel Kant's philosophy. He's dedicated to evidence-based medicine, writing, and passionately cheering for the Hoosiers and Cowboys sports teams.

To schedule an appointment with Dr. Schumacher and the Southwest Pulmonary Associates team, call the office or request an appointment online today.

Tayler Long, MD, is a board-certified pulmonologist at Southwest Pulmonary Associates in Plano, Texas. He is committed to providing excellent pulmonary and critical care medicine to the community. 

Dr. Long earned his Bachelor of Arts in Human Biology from Stanford University in Palo Alto, California, before completing his Doctor of Medicine at the University of California, San Diego School of Medicine. He went on to complete both his residency in Internal Medicine and his fellowship in Pulmonary and Critical Care Medicine at the prestigious UT Southwestern Medical School in Dallas, Texas.

In addition to his clinical training, Dr. Long holds a Master of Science in Healthcare Leadership and Management from UT Dallas, equipping him with the tools to lead effectively in today’s evolving healthcare landscape. His advanced education and years of experience allow him to offer expert care in managing complex lung diseases, respiratory failure, and critical illness.

Dr. Long joined Southwest Pulmonary Associates in 2007. He has served as President of the Medical Staff at Texas Health Plano and currently holds leadership roles on the Medical Executive Committee at Texas Health Frisco. He also serves as the Director of the ICU at Texas Health Frisco, reflecting his commitment to both patient care and institutional excellence. He is has been recognized as one of D Magazine's Best Docs repeatedly, most recently in 2025.

Outside of medicine, Dr. Long is a devoted husband and father. He is married and enjoys spending time with his three beautiful children.

Mark Robertshaw, MD, is a board-certified pulmonologist and critical care medicine specialist proudly serving patients in Plano, Texas. He joined Southwest Pulmonary Associates in 2023, bringing with him a wealth of clinical experience and a compassionate, patient-centered approach to care.

Dr. Robertshaw completed his fellowship in Pulmonary and Critical Care Medicine at UT Southwestern Medical Center in Dallas, Texas, where he was honored to serve as Chief Fellow during the 2022–2023 academic year. He completed his residency training at Duke University Hospital in Durham, North Carolina, and earned his medical degree from the University of Missouri in Columbia. His academic journey began at the University of Notre Dame in South Bend, Indiana, where he received his Bachelor of Science and developed a lifelong passion for Fighting Irish football.

Board certified by the American Board of Internal Medicine in both Pulmonary Medicine and Critical Care Medicine, Dr. Robertshaw is committed to helping patients manage a wide range of respiratory conditions with leading-edge diagnostic tools and individualized treatment plans. His dedication to community service has been recognized with prestigious honors, including the President’s Volunteer Service Award and the Congressional Award, both received in 2013.

Outside the clinic, Dr. Robertshaw enjoys spending quality time with his wife and daughter, golfing, and cheering on his alma mater during college football season. He looks forward to building long-lasting relationships with his patients and their families throughout the Plano community.

Rebecca Doebele, MD, is a board-certified pulmonologist and critical care specialist who has been providing expert respiratory care to patients in Dallas, Texas, since joining Southwest Pulmonary Associates in 2008. Known for her compassionate approach and clinical excellence, Dr. Doebele treats a wide range of pulmonary conditions, including asthma, COPD, interstitial lung disease, and critical illnesses requiring intensive care.

Dr. Doebele earned her Bachelor of Science in Genetics from Texas A&M University in College Station before completing her Doctor of Medicine at the University of Texas Southwestern Medical School in Dallas. She remained at UT Southwestern for her residency in Internal Medicine, then pursued advanced fellowship training in Pulmonary and Critical Care Medicine at the University of Colorado Health Science Center.

Board-certified in both Pulmonary Medicine and Critical Care Medicine by the American Board of Internal Medicine, Dr. Doebele has been repeatedly recognized for her clinical skill and dedication to patient care. She was named a Super Doctors Rising Star in 2012 and has earned the prestigious Texas Super Doctors distinction annually from 2013 to the present. Additionally, she received the “Physician All-Star” award from the nursing and administrative staff at Texas Health Presbyterian Hospital of Dallas, a testament to her leadership and collaboration in the hospital setting. Dr. Doebele has been recognized as one of D Magazine’s best doctors in 2021, 2023, and 2024. She also serves as the ICU Medical Director at Texas Health Dallas. 

Outside of medicine, Dr. Doebele enjoys traveling and spending time with her husband and their three children. She is proud to serve the Dallas community and is committed to helping her patients breathe easier and live healthier lives.