Your heart rate naturally changes through the day, speeding up with activity, stress or caffeine and slowing down during rest and sleep. A change in heart rhythm is different: the heart beats too fast, too slowly, or irregularly, because the electrical signals that coordinate each heartbeat are not working normally. People describe it as fluttering, pounding, skipped beats, a flip-flop in the chest, or a racing heart that starts and stops suddenly. Some people feel nothing at all, and the problem is found on an exam or ECG.
Many rhythm changes are harmless, such as occasional extra beats. Others, particularly atrial fibrillation, raise the risk of stroke or heart failure and need treatment. The National Heart, Lung, and Blood Institute notes that untreated arrhythmias can lead to stroke, heart failure or cardiac arrest, and that most are treatable with medicine or procedures. Our internal medicine physicians evaluate palpitations and irregular rhythms, identify the type, look for the cause, and coordinate specialist care when it is needed.
Common rhythm changes and their causes
Premature beats (PACs from the upper chambers and PVCs from the lower chambers) are extra beats that feel like a skip or a thump. They are very common and usually benign, though frequent PVCs sometimes need evaluation of heart function. Atrial fibrillation (AFib) is a chaotic, irregular rhythm from the upper chambers. It becomes more common with age, high blood pressure and heart disease, and it matters mainly because blood can pool and clot in the heart and travel to the brain. Supraventricular tachycardia (SVT) is a regular racing rhythm that starts and stops abruptly, often in younger, otherwise healthy people. Bradycardia is a slow rhythm, which can be normal in fit people but can also reflect disease of the heart's electrical system or medication effects, and may cause fatigue, dizziness or fainting.
Rhythm problems often have triggers or underlying causes. The Mayo Clinic lists too much caffeine or alcohol, smoking and stimulant drugs, an overactive or underactive thyroid, obstructive sleep apnea, electrolyte imbalances such as low potassium or magnesium, certain cold and allergy medicines, stress, high blood pressure, diabetes, prior heart attack and coronary artery disease. Scarring of the heart muscle and cardiomyopathy are other important causes. Finding and correcting these is part of treatment.
How we evaluate heart rhythm changes at NYMD Center
We begin with a careful history: what you feel, how often, how long each episode lasts, whether it starts suddenly, and whether it comes with dizziness, fainting, chest pain or breathlessness. We review caffeine, alcohol, supplements, medications and sleep, and ask about snoring or daytime sleepiness that could suggest sleep apnea. We examine your heart, check your pulse and blood pressure, and look for signs of thyroid or heart disease.
An ECG (EKG) is done in the office and can identify the rhythm if it is happening at the time, as well as signs of prior heart damage or conduction problems. Because many rhythm changes come and go, an ambulatory ECG monitor worn at home for a day or longer is often the key test for catching episodes. When needed, we arrange an echocardiogram to check the heart's structure, pumping strength and valves, which shapes both the risk and the treatment. Blood work includes thyroid function, electrolytes including potassium and magnesium, kidney function and a blood count. Stress testing or a sleep study is arranged when the history points there.
Treatment options
Treatment depends on the specific rhythm, how much it affects you, and whether it carries risk. Many patients need nothing more than reassurance and removal of triggers.
Reducing triggers and treating causes
Cutting back on caffeine and alcohol, stopping smoking and stimulants, improving sleep and treating sleep apnea can reduce or eliminate episodes. Correcting an electrolyte imbalance or treating thyroid disease can resolve the rhythm entirely. Controlling blood pressure and weight lowers the risk of AFib returning. For SVT, simple vagal maneuvers such as bearing down can sometimes stop an episode, and we can teach you how.
Medication
Beta blockers or calcium channel blockers slow a fast heart rate and reduce symptomatic extra beats. Antiarrhythmic drugs are used in some patients to keep a normal rhythm. These medications can cause fatigue, low blood pressure or, occasionally, rhythm side effects of their own, so they are monitored with follow-up ECGs.
Stroke prevention in atrial fibrillation
For people with AFib, the most important decision is often whether to take a blood thinner. The 2023 ACC/AHA atrial fibrillation guideline bases this on yearly stroke risk estimated with a validated score such as CHA2DS2-VASc, which counts factors including heart failure, high blood pressure, age, diabetes, prior stroke, vascular disease and sex. Blood thinners lower stroke risk but raise bleeding risk, so we weigh both with you. Beyond that, AFib is managed with rate control, which slows the heart, or rhythm control, which aims to restore and keep a normal rhythm.
Procedures by referral
When medication does not control symptoms or is not tolerated, we refer to cardiology and electrophysiology. Options include cardioversion to reset the rhythm, catheter ablation to treat the tissue causing AFib, SVT or some PVCs, and a pacemaker for a dangerously slow rhythm. People at risk of life-threatening rhythms may need an implantable cardioverter-defibrillator. These procedures are effective for the right patients but carry procedural risks and recovery time, so they follow a careful specialist evaluation. Our cardiology page describes how we coordinate this care.
What to expect at your visit
Plan on a history, an exam, an ECG and usually a blood draw. If your symptoms come and go, we will likely place a Holter monitor in our office. Bring your medication and supplement list, any readings or tracings from a smartwatch or home device, and prior ECGs or hospital records. Keeping a short log of episodes, with the time, what you were doing and how long each lasted, is very helpful.
When to seek care urgently
Call 911 for a racing or irregular heartbeat with fainting or near-fainting, chest pain, significant shortness of breath, or any stroke symptoms such as facial droop, weakness or numbness on one side, trouble speaking or sudden vision loss. Do not drive yourself. Call us the same day for a new irregular rhythm, palpitations that are lasting longer or happening more often, or a very slow pulse with dizziness or fatigue.
Questions patients ask
Are skipped heartbeats dangerous?
Occasional skipped or extra beats, called PACs or PVCs, are very common and usually harmless, especially with a normal heart. They are often triggered by caffeine, alcohol, stress or poor sleep. We check an ECG and sometimes place a Holter monitor in the office or arrange an echocardiogram, particularly if the beats are frequent, come with dizziness or fainting, or you have known heart disease.
What is atrial fibrillation and why does it matter?
Atrial fibrillation is a chaotic, irregular rhythm in the heart's upper chambers. It can cause palpitations, fatigue and breathlessness, but its biggest danger is stroke, because blood can pool and form clots that travel to the brain. We assess your stroke risk with a validated score such as CHA2DS2-VASc and discuss whether a blood thinner is right for you.
How do you catch a rhythm problem that comes and goes?
An in-office ECG only records a few seconds, so intermittent rhythms are often missed. An ambulatory ECG monitor worn at home for a day or longer records your heart continuously, and you mark when symptoms happen. Matching symptoms to the recording tells us whether a rhythm problem is responsible.
Can my smartwatch detect an irregular heartbeat?
Many smartwatches can flag a possible irregular rhythm and record a single-lead tracing. That information is useful, and we are glad to review it, but it does not replace a full ECG or a medical-grade monitor. If your watch alerts you to a possible irregular rhythm, schedule an evaluation rather than ignoring it.
When is a fast heartbeat an emergency?
Call 911 if a racing or irregular heartbeat comes with fainting or near-fainting, chest pain, significant shortness of breath, or stroke symptoms such as facial droop, one-sided weakness or trouble speaking. Do not drive yourself. A fast rhythm without those symptoms should still be evaluated promptly, usually the same day.