Dr. Dennis Cassidy, MD

Dr. Dennis Cassidy, MD

Clinical Cardiac Electrophysiology  ·  
Male  ·  
66 y/o

Accepting new patients

Dr. Dennis Cassidy, MD is a clinical cardiac electrophysiologist in Saint Petersburg, FL and has been practicing for 33 years. He specializes in clinical cardiac electrophysiology, cardiology, and more.Read his story

The Heart Institute

6006 49th St N Ste 200

Saint Petersburg, FL 33709
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Insurance Accepted

  • Accepts most major Health Plans. Please contact our office for details.
  • Aetna
  • Blue Cross Blue Shield
  • Cigna
  • Coventry Health Care
  • First Health (Coventry Health Care)
  • Humana
  • MultiPlan
  • UnitedHealthCare
  • WellCare

Learn about Dr. Cassidy

Be confident in your decisions by checking out your provider's top areas of care, education, patient reviews and more. Learn about finding the right doctor for you.

Top Care Areas

See how frequently Dr. Cassidy performs your care needs compared to other doctors.

Heart Disease
very high
more than 94% of peers
Cardioversion, Elective
very high
more than 91% of peers
Cardiac Electrophysiology
very high
more than 90% of peers

Dr. Cassidy's percentages are based on the rate of treatment compared to peers nationwide from insurance data. Learn more info about our data and this Top Care Areas component.

Dr. Cassidy's bio

This content was provided by Dr. Cassidy "Dennis Cassidy, MD, FACC, FHRS received his medical degree and completed his internship at Memorial University in St. Johns, Newfoundland, Canada. He completed his internal medicine training at the University of Toronto, Toronto, Ontario, Canada and his cardiology residency at Queen?s University in Kingston, Ontario, Canada. He then specialized in clinical cardiac electrophysiology at the Hospital of the University of Pennsylvania in Philadelphia, Pennsylvania.Dr. Cassidy is board certified in Internal Medicine, Cardiology, and Clinical Cardiac Electrophysiology. He specializes in the field of cardiac electrophysiology, which deals with disorders of the electrical system of the heart. He has expert training in the area of implantation and management of pacemakers, cardiac defibrillators, electrophysiology, and catheter ablation procedures. He is a member of the American Heart Association and a Fellow of the American College of Cardiology and Heart Rhythm Society."
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Care Philosophy

This content was provided by Dr. Cassidy "We have forged in new frontiers of cardiovascular care and treatment through advances in nuclear medicine, cutting edge technology and research, and the development of preventive and educational services. Coupled with highly trained physicians and medical staff, The Heart & Vascular Institute has established itself as a "Center of Excellence" in the care and treatment of cardiovascular disease."

3  Specialties

  • Clinical Cardiac Electrophysiology
  • Cardiology
  • Interventional Cardiology

3  Board Certifications

  • Cardiovascular Disease
    Accredited by: American Board of Internal Medicine*
  • Clinical Cardiac Electrophysiology
    Accredited by: American Board of Medical Specialties*
  • Internal Medicine
    Accredited by: American Board of Internal Medicine*

50  Conditions Treated

  • Aneurysm
  • Aneurysm of Heart
  • Angina and Acute Coronary Syndrome
  • Aortic Aneurysm
  • Aortic Dissection
  • Aortic Ectasia
  • Aortic Stenosis
  • Aortic Valve Disease
  • Aortic Valve Regurgitation
  • Arrhythmias
  • Atrial Fibrillation
  • Atrial Flutter
  • Autonomic Disorders
  • Autonomic Dysreflexia
  • Cardiomegaly
  • Cardiomyopathy
  • Carotid Artery Disease
  • Chest Pain
  • Chronic Pulmonary Heart Diseases (incl. Pulmonary Hypertension)
  • Congenital Heart Defects
  • Congenital Heart Disease
  • Congestive Heart Failure
  • Coronary Artery Disease (CAD)
  • Endocarditis
  • Heart Attack (Acute Myocardial Infarction)
  • Heart Disease
  • Heart Murmur
  • Heart Palpitations
  • Hyperlipidemia
  • Hypertension
  • Hypertensive Chronic Kidney Disease
  • Hypertensive Heart and Chronic Kidney Disease
  • Hypertensive Heart Disease
  • Hypotension
  • Limb Swelling
  • Limb Swelling Caused by Fluid Overload
  • Mitral Valve Disease
  • Mitral Valve Regurgitation
  • Mitral Valve Stenosis
  • Palpitations
  • Pericardial Disease
  • Pulmonary Disease
  • Pulmonary Edema
  • Pulmonary Hypertension
  • Pulmonary Valve Disease
  • Septal Defect
  • Syncope
  • Thrombosis
  • Tricuspid Valve Disease
  • Vascular Disease
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26  Procedures

Background Check

0 Malpractice Claims

No malpractice history found for Florida.

0 Sanctions

No sanctions history found for the years that Healthgrades collects data.

0 Board Actions

No board actions found for the years that Healthgrades collects data.


  • Memorial University Of Newfoundland
    Undergraduate School | Graduated 1976
  • Memorial Hospital
    Medical School | Graduated 1978
  • Memorial University Of Newfoundland Faculty Of Medicine
    Medical School | Graduated 1978
  • Meml University
    Internship Hospital | Completed 1979
  • Memorial Hospital
    Residency Hospital | Completed 1982
  • Queens University
    Residency Hospital | Completed 1982
  • University of Toronto
    Residency Hospital | Completed 1980
  • Hospital Of The University Of Pennsylvania
    Fellowship Hospital | Completed 1985

Awards & Recognition

Awards & Honors
  • Healthgrades Honor Roll
Media & Publications

Dr. Cassidy has no media or publications listed.

Languages Spoken

  • English
  • Spanish

Memberships & Professional Affiliations

Dr. Cassidy does not have any memberships or affiliations listed. If you are Dr. Cassidy and would like to add memberships or affiliations, please update your profile.

Dr. Cassidy's Reviews

Likelihood to recommend Dr. Cassidy


Based on 15 reviews

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Average Wait Time
  • Under 10 minutes
Dr. Cassidy's Performance
  • Trustworthiness
  • Explains condition(s) well
  • Answers questions
  • Time well spent
Office & Staff Performance
  • Scheduling
  • Office environment
  • Staff friendliness
What People Say About Dr. Dennis Cassidy, MD
Dr. Cassidy is great! After seeing many doctors who just wanted to jump the gun and do surgery on my heart he took the time to try medications to manage my condition. 4 years later I am doing much better and did not need surgery.
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Stef in Tampa, FL – Sep 19, 2018
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He was very detailed on giving me the information on my heart . He spent the needed time with me
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Feb 03, 2018
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I met Dr Cassidy after an emergency room visit for a serious AFIB incident. He has been my cardiologist since. I recommend this Dr. To anyone seeking.an expert, Caring, and proficient cardiologist.
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Meri in At. Petersburg, FL – Aug 14, 2017
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Dr. Cassity explained all the various options of treatment. He took the time to listen my ideas, and then he answered all my questions. There was no pressure to follow a certain treatment.
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St Petersburg, FL – Aug 14, 2017
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Very likely
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John Edwards in St Petersburg, FL – Jul 27, 2017
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