Palpitations, Syncope, & Dysrhythmias Study Notes

Palpitations

  • Definitions:

    • Pounding, racing, flopping, fluttering, flipping sensations in the chest.

    • Focus on differentiating high-risk individuals needing intensive evaluation from low-risk persons.

    • Sudden changes in rate/rhythm may result in increased stroke volume (SV) or contractility, leading to sensations of palpitations.

Patient History

  • Obtain a detailed description of the sensation.

  • Symptoms can include:

    • Strong but regular rhythms during stress or exertion are possibly normal.

    • Skipped beats could indicate ectopic beats.

Types of Ectopic Beats

Atrial Ectopic Beats

  • Possible Causes:

    • Excessive caffeine, ethanol (ETOH), tobacco use.

    • More likely to occur in patients with Chronic Obstructive Pulmonary Disease (COPD), Rheumatic Heart Disease (RHD), and valve diseases.

Ventricular Ectopic Beats

  • More likely associated with cardiac pathology.

  • Patients may face increased risk for sudden cardiac death.

Sudden Onset Palpitations

  • Can be caused by:

    • Supraventricular Tachycardia (SVT) or Ventricular Tachycardia (VT).

    • Atrial Fibrillation (AF).

  • Co-symptoms to inquire about:

    • Chest pain, shortness of breath (SOB).

Diagnostics for Palpitations

  • Thyroid Stimulating Hormone (TSH) levels.

  • Electrolytes check.

  • Hemoglobin (H), Hematocrit (H) levels.

  • Holter monitor for continuous heart rhythm tracking.

  • Echocardiogram.

Management of Palpitations

  1. Patient presents with palpitations:

    • Take full history, perform physical examination, obtain ECG.

    • Rule out structural heart disease and extraneous causes.

      • Treat underlying drug use, hyperthyroidism, etc.

      • If no structural heart disease:

        • Obtain complete CBC, chemistry profile, TSH, and screen for drug use if appropriate.

        • Echocardiography or Holter/event monitoring can be initiated based on findings.

  2. Daily palpitations:

    • If less than daily, initiate transtelephonic event monitoring for two weeks.

    • If palpitations occur during normal sinus rhythm, consider nonventricular vs. ventricular arrhythmias.

  3. Reassurance for nonventricular arrhythmias:

    • Treat ventricular arrhythmias if identified; may need to refer to a cardiologist.

    • For high-risk patients, consider electrophysiologic evaluation.

Another Algorithm for Palpitations

  • Steps:

    1. Detailed history, examination, ECG, and lab tests (TSH, CBC, CMP).

    2. Determine if sustained arrhythmia or poorly tolerated.

    3. Classify as high risk for arrhythmias or suggestive of arrhythmia/not suggestive.

    4. If symptoms persist and ECG doesn’t reveal issues, further observation or urgent consults may be warranted.

Syncope

  • Definition:

    • Temporary loss of consciousness (LOC) and postural tone followed by spontaneous recovery without requiring resuscitation.

  • Presyncope/Near Syncope:

    • Sensation of lightheadedness or faintness, but not complete LOC; a symptom of an underlying process.

Emergency concerns in Syncope

  • Consider if syncope occurs with:

    • Family History (FHx) of sudden death.

    • Associated with exercise, chest pain (CP), Congestive Heart Failure (CHF), palpitations, known or suspected arrhythmia, ischemia, acute hemorrhage, Transient Ischemic Attacks (TIAs), stroke, or seizures.

    • Presence of abnormal ECG, abnormal chest X-ray (CXR), or personal medical history of anatomic heart disease (PMH).

Pathophysiologic Mechanisms of Syncope

  • Deprivation of nutrients or oxygen to the brain due to:

    • Decreased cerebral blood flow.

    • Hypovolemia, cardiac outflow obstruction, or arrhythmias.

  • Neurovascular etiology due to hypoxemia or anemia.

Cardiac Causes of Syncope

  1. Mechanical/Obstructive Causes:

    • Valvular disease, atrial myxoma, cardiomyopathy, pulmonary hypertension (HTN), pulmonary embolism (PE), pericardial disease, cardiac tamponade, myocardial infarction (MI) or ischemia.

  2. Arrhythmias:

    • Sick sinus syndrome, AV conduction disturbances, SVT, VT, prolonged QT syndrome, pacemaker malfunction.

Neurologic Causes of Syncope

  1. Reflex/Neuromediated Causes:

    • Vasovagal (common faint preceded by unpleasant stimuli), situational (post cough, defecation, micturition), carotid sinus hypersensitivity (turning head, tight shirt collar).

  2. Cerebrovascular Issues:

    • Vertebrovascular TIAs, subclavian steal syndrome, seizure disorder (not true syncope).

Miscellaneous Causes of Syncope

  • Hypoglycemia, psychiatric disorders, hyperventilation, hypovolemia.

Syncope: Presentation Assessment

  • Obtain detailed history for clues to etiology:

    • Vasovagal: sudden weakness, nausea, sweating, emotional triggers.

    • Hypovolemia: orthostatic hypotension.

    • Seizure (not true syncope): aura, incontinence.

    • Cardiac: associated with exertion, CP, family history (FH).

    • Medication history: volume depleters, anti-hypertensive, anti-arrhythmic drugs.

    • Social history: drug/alcohol use, occupation.

Syncope: Differential Diagnosis of Dizziness

  • Dizziness definitions might include fainting, giddiness, risk of falling, or light-headedness.

  • Types of dizziness may be classified under:

    • Syncope or near syncope, disequilibrium, cardiovascular disorders, non-vestibular neurologic disorders, orthostatic hypotension, cardiac arrhythmias, hypersensitive carotid sinus, vasodepressor spells (vasovagal syncope), valvular or subvalvular stenosis, cerebellar disorders, peripheral or central vestibular disorders, psychiatric disorders (anxiety and/or depression).

Syncope Physical Exam Findings

  • Cardiovascular assessment for postural signs:

    • Presence of murmurs, arrhythmias, S3/S4 sounds, jugular venous distention (JVD), hepatojugular reflux, and edema.

    • Orthostatic blood pressure measurements should be conducted from supine to sitting and standing positions.

  • Neurological assessment:

    • Complete neurological and fundoscopic examination.

    • Consider GI/rectal examination for suspected hemorrhage.

Syncope Diagnostics

  • Initial tests include:

    • ECG monitoring, Holter monitoring, continuous loop event reporter if ECG is unrevealing, pulse oximetry.

  • If ECG and history do not offer clues:

    • Laboratory tests: electrolytes, BUN, creatinine, glucose, H/H.

    • Pregnancy test (HCG) for females of childbearing age.

    • Cardiac isoenzymes if cardiac etiology suspected.

  • Imaging may include echocardiography, CT/MRI of the head if indicated, and carotid ultrasound.

Syncope Management Options

  • For cases without cardiac issues or urgent concerns:

    • Education on fluid volume, gradual positional changes, increased dietary salt intake, and reassurance about condition.

    • Referral to cardiology or neurology for treatment of underlying causes may be necessary.

    • Consider consult for psychiatric evaluation if relevant.

Arrhythmias

  • Types:

    • Supraventricular arrhythmias, including premature atrial contractions (PACs) and sinus tachycardia.

    • Etiologies include: fever, severe anemia, hyperthyroidism, anxiety, panic disorders, agitated depression.

    • SVTs can be precipitated by excess alcohol consumption, emotional upset, physical exertion, pre-excitation syndromes like Wolff-Parkinson-White (WPW), and others.

Atrial Fibrillation (AF)

  • Definition: An irregularly irregular rhythm.

  • Classification:

    1. Paroxysmal AF: Two or more episodes that terminate spontaneously within 7 days.

    2. Persistent AF: Lasting over 7 days.

    3. Permanent AF: Lasting over a year.

  • Epidemiology: Prevalence increases with age; from 0.1% in adults <55 years to 9% in adults >80 years. Men > women.

  • Chronic AF develops in 25% of paroxysmal AF patients within 5 years.

  • Increased cerebrovascular accident (CVA) risk, 5 times in AF patients.

  • Higher risk of developing heart failure.

Atrial Fibrillation Symptoms and Significance

  • Patient experiences: palpitations, dizziness, lightheadedness, fatigue, weakness, impaired exercise tolerance, angina, and dyspnea.

  • Some patients may be asymptomatic.

  • Heart sounds observed are irregularly irregular:

    • Controlled AF typically shows heart rates <85 beats per minute (BPM) at rest.

    • Uncontrolled AF shows rates >110 BPM at rest, and rapid AF rates can range from 120 to 180 BPM.

Causes of Atrial Fibrillation

  • Common causes:

    • Hypertensive heart disease, valvular heart disease, pulmonary embolism, chronic obstructive pulmonary disease (COPD), sleep apnea, carbon monoxide poisoning, pericarditis, myocarditis, cardiomyopathy, congestive heart failure (CHF), coronary artery disease (CAD), myocardial infarction (MI), congenital heart disease, atrial septal defect (ASD), tachy-brady syndrome.

  • Endocrine factors: WPW, atrial tachycardias, thyrotoxicosis, hyperthyroidism, obesity, and pheochromocytoma.

  • Surgery: cardiac and non-cardiac surgeries may precipitate AF.

  • Electrolytic influences: hypokalemia, hypomagnesemia, fever, anemia, hypoxia, sepsis, infections, and porphyrias.

  • Risk from medications: digoxin, theophylline, amphetamines, cocaine, antihistamines, ethanol (ETOH), caffeine, NSAIDs.

Atrial Fibrillation Differential Diagnosis and Management

  • Differential diagnoses include multifocal atrial tachycardia, atrial flutter (A-flutter), and PACs.

  • Workup involves ECG, echocardiogram, Holter monitoring, TSH levels, electrolytes, and toxicity screens.

  • Treatment options include pharmacological management or cardioversion depending on rate, duration, and patient stability.

  • The biggest risk associated with AF is CVA; anticoagulation remains the mainstay of treatment.

Atrial Flutter

  • Characteristic findings include a classic sawtooth pattern.

  • Atrial fibrillation can deteriorate into A-flutter, with underlying causes being the same as AF.

  • Cardioconversion is typically easier for A-flutter than for AF, requiring 25-50 joules of energy.

  • Patients with AF or A-flutter should generally be referred to cardiology for further evaluation and treatment.

Arrhythmias: Ventricular Dysrhythmias

  • Premature Ventricular Contractions (PVCs):

    • Most PVCs in the absence of cardiac disease have limited diagnostic value.

    • If occurring in the recovery phase of stress testing, they indicate increased long-term mortality risk.

Ventricular Tachycardia (VT)

  • Considered the most worrisome dysrhythmia due to its association with the risk of sudden cardiac death.

  • Non-sustained VT (NSVT) may be idiopathic or associated with heart disease.

  • Increased risk for ventricle tachycardia.

Arrhythmias Physical Examination

  • Conduct a general survey assessing vital signs, checking for elevated blood pressure, marked postural changes, and temperature.

  • Skin findings may indicate pallor, anemia, or hyperthyroidism (including exophthalmos).

  • Cardiac examination:

    • Check for murmurs, arrhythmias, and other significant heart sounds (e.g., S3, S4).

  • Assess for any extremity edema or calf tenderness.

  • Neurological/Psych: Inquire about anxiety, panic issues, and confusion.

Patient Education Regarding Arrhythmias

  • Key Messages:

    • Reassurance for harmless dysrhythmias when found to be merely due to excessive bodily concern.

    • Prevention involves avoiding known triggers:

    • OTC products containing ephedra (banned by the FDA in the USA), sympathomimetics (common in decongestants and diet pills), and caffeine.

Arrhythmias Diagnostics

  • Tests:

    • ECG monitoring, blood tests (hemoglobin, TSH, electrolytes, finger stick for blood glucose), ambulatory ECG monitoring, event recorders, exercise stress testing, echocardiograms, and electrophysiological studies.

Arrhythmias Treatment

  • For Atrial and Ventricular Premature Beats:

    • Suggest relaxation therapy and low-dose beta-blockers (e.g., atenolol or metoprolol 25-50 mg daily).

  • For Supraventricular Tachycardia (SVT):

    • Consider vagal maneuvers.

  • For Sinus Tachycardia:

    • Address underlying precipitating factors (e.g., anemia, thyroid disease, fever, volume depletion).

  • For Ventricular Tachycardia (VT):

    • Provide emergency care if symptomatic.