CARDIOVASCULAR CONCERNS
| ATRIAL FIBRILLATION —David G. Benditt, MD, Professor of Medicine, and Co-Director of Cardiac Arrhythmia
Center, University of Minnesota Medical School, Minneapolis
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| Introduction: incidence likely to increase in next 10 to 20 yr; atrial fibrillation and related atrial tachycardia often
unrecognized in younger age group; therapeutic approaches—can prevent atrial fibrillation and adverse effects;
surgical procedures (eg, Mustard or Senning operations); conditions identified on electrocardiography (ECG; eg,
Wolff-Parkinson-White syndrome) more prevalent than originally suspected and can lead to atrial arrhythmias at
earlier age
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| Management strategy: therapeutic goal depends on individual patient; rhythm control—to prevent atrial fibrillation
recurrences; rate control—for permanent atrial fibrillation; anticoagulation—for older patients and younger patients
who have underlying structural heart disease, hypertension, diabetes, or history of stroke
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| Rate control: not defined as administration of α-blockers, calcium channel blockers, or digoxin; implies patient has
appropriate heart rate (HR) for usual activities; involves protocol that tests treatment to determine whether HR acceptable
and not excessively fast; use monitoring (eg, Holter); safety—consider adverse drug effects (eg, fatigue,
lengthened QT interval); be cautious in older patients and patients with significant underlying structural heart problems;
other options—eg, ablation; consider for patients with intermittent episodes that disturb lifestyle or patients
hemodynamically difficult to control; drugs—digoxin and related cardiac glycosides “falling off the table” and not
effective, but may be helpful to patients with heart failure and atrial fibrillation; α-blockers; calcium channel blockers;
antiarrhythmic drugs (eg, sotalol, amiodarone) difficult for patients to tolerate and should be reserved for extraordinary
circumstances; rate control preferred for older patients
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| Rhythm control: preferred for younger patients, patients with no underlying heart disease, and patients with severe
heart disease who do not tolerate atrial fibrillation; in absence of heart disease, many drugs (eg, flecainide, propafenone,
sotalol, amiodarone, quinidine, procainamide) available; if heart disease present, choice of drugs restricted
due to adverse effects of drugs; more difficult and less safe to suppress atrial fibrillation in patient with
significant underlying heart disease; safer drugs include sotalol, dofetilide, and amiodarone
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| Ablation: for selected young to middle-aged patients with modest structural heart disease; episodes of atrial fibrillation
usually disturbing to lifestyle or hemodynamically disturbing; radiofrequency ablation—standard; tip of catheter
heated with radiofrequency energy to cause cautery lesions; localized or large areas can be ablated; cryoablation—at
tip of electrode, nitrogen gas freezes tissue locally; creates homogenous lesion (less arrhythmogenic); can be used palliatively;
standard for atrioventricular (AV) node reentry, Wolff-Parkinson-White syndrome, and ventricular tachycardias;
atrial arrhythmias more difficult to pinpoint and only more recently amenable by ablation (reentry circuits small
and difficult to repair with single or few localized lesions); ablation widely used; multiple-strategy approach; can reduce
or eliminate episodes; some older frail patients not good candidates for procedure and may undergo ablation of
conduction between atria and ventricle (AV junctional ablation; effective; pacemaker required; increases patient comfort)
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| Techniques for ablation: cauterize trigger sites (rapidly firing cells in pulmonary vein); finding trigger sites requires
approaching left atrium (ie, perforating interatrial septum), inserting catheters, and importing computed tomography
(CT) and magnetic resonance imaging (MRI) studies into electrical mapping system; insert additional catheters and
determine origin of abnormal electrical activity in vein; avoid burning entire pulmonary vein (can result in obstruction,
late stenosis, or pulmonary hypertension); subselective ablation—burning to where electrical activity emanates
from vein; loop long ablation lines around veins to minimize interference with atrial conduction; long-term results—
after 2-yr follow-up, episodes suppressed in 70% to 80% of patients (20%-25% of patients suppressed with added
drugs); complications—transseptal catheterization; tissue damaged by radiofrequency energy
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| Syncope: transient loss of consciousness without trauma; due to self-limited loss of blood supply to brain, mainly
caused by reduction in blood pressure (BP); usually presents in men 50 to 60 yr of age; women of all ages report
syncopal episodes (uncertain whether women more likely to report episodes than men); seen in young patients;
men less likely to complain than women; vasovagal syncope (common faint) most frequent diagnosis; more serious
forms of syncope occasionally missed; neurally mediated reflex faints most common; carotid sinus syncope in
older patients (>70 yr of age) difficult to diagnose; orthostatic faints common; autonomic nervous system disease
rare
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| Differentiating syncope from seizures: myoclonic jerking—common in syncope and usually begins after loss of consciousness
(begins before loss of consciousness in patients with seizure); pallor—more common in syncope than in
seizures; loss of consciousness—usually brief (1-2 min) in patients with syncope; extended in patients with seizure;
tongue biting rare; fatigue—common in vasovagal fainters; consider syncope if patients fatigued; syncope patients
often have difficulty standing or moving for several minutes
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| Management of syncope: detailed patient history important; presence of heart disease worsens prognosis (further
evaluation may be needed); origin of most syncope cardiac or cardiovascular and rarely neurologic; for cardiovascular
complaints, most syncope associated with arrhythmia; ambulatory ECG recorders may be useful; conventional
Holter recorder or conventional event recorder may not be useful unless patient has frequent episodes;
wearable event recorders better than Holter recorders but have limited recording time and patient must be competent;
mobile outpatient cardiac telemetry available; insertable loop recorders useful for patients who faint once or
twice per year
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| Neurally mediated events: tilt-table testing for difficult-to-diagnose patients who have atypical history; vasovagal
syncope—patient education; tilt training to improve neurovascular response to upright posture; avoid drugs, but
some vasoconstrictors may be useful; cardiac pacemakers usually unnecessary; carotid sinus syndrome—usually
seen in older patients; orthostatic syncope—can occur in all age groups; check salt volume; support hosiery may be
helpful; syncope due to arrhythmias—for life-threatening cases, antiarrhythmic drugs and implantable cardioverter
defibrillators (ICDs) used; pacemakers effective for bradyarrhythmias
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| Other conditions that cause vasovagal syncope: long QT syndrome—drug-induced or primary; becoming more
prevalent; be aware of which drugs cause long QT problems and monitor patients; hypertrophic cardiomyopathy—
can cause sudden death; identify early in patients who present with lightheadedness or syncope; Brugada syndrome
and other channelopathies—genetic maladaptions of conduction channels increasingly recognized; astute diagnosis
can prevent untimely deaths; patients often present first with syncope
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| CHEST PAIN —Loren A. Crown, MD, Clinical Professor of Family Medicine, University of Tennessee Health Science
Center, College of Medicine, Memphis
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| Introduction: patient history, risk factors, and current medications important; physical examination—check whether
patient diaphoretic, pale, or gasping; patients usually appear normal; palpate chest wall; look for musculoskeletal
involvement and red dimples across dermatomes on backside; auscultation may be helpful; chest x-ray; abdominal
palpation may be helpful
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| Diagnostic tests: perform ECG, check cardiac enzymes, give aspirin and nitrate, and start O2 therapy; give intravenous
(IV) morphine if pain continues; check cardiac markers at 0, 3, 6, and 9 hr; immediately reassess patient if complaints
change; gastrointestinal (GI) cocktails or nitroglycerin not diagnostic; ECG and chest x-ray good for baseline (normal
values do not rule out coronary artery disease [CAD]); exercise treadmill testing—sensitivity and specificity “not that
great”; look for chest pain, hypotension, ST depression, and ventricular tachycardia; exercise echocardiography—
can be combined with exercise treadmill testing or stress drug testing; slightly less sensitive but slightly more specific
than exercise thallium testing; exercise thallium testing—can be combined with exercise treadmill testing or exercise
echocardiography; more expensive; requires more time; pharmacologic testing—can be combined with other tests;
causes normal coronary arteries to vasodilate more than arteriosclerotic vessels (demonstrates perfusion abnormality;
positive result on thallium testing); cardiac catheterization gold standard; CT of heart—$99; available in shopping
centers; provides indeterminate calcium score
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| Pediatric evaluation: chest pain in children usually benign; questions to ask for determining whether patient has hypertensive
cardiomyopathy—“do you have chest pain when you play too hard?”; “do you pass out or get faint when
you play too hard?”; “do you have anybody in your family who has dropped dead suddenly at an early age from a
heart problem?”
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 | Chest wall: cutaneous and subcutaneous tissue—herpetic lesions; panniculitis; fibrocystic disease; infection; tumor;
muscles—fibromyalgia; myofascitis; myositis; rhabdomyolysis; ribs and nerves—Tietze syndrome (costochondral
inflammation); xiphoidalgia; fractures; spinal cord—rheumatoid arthritis; epiphysitis; spondylitis;
thoracic outlet syndrome; shoulders—referral point; chest pain can radiate to jaw or left shoulder; perform
ECG and chest x-ray; look for arthritis, bursitis, tendinitis, rotator cuff injury, and shoulder impingement syndrome
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| Thorax: pleura—pleurisy provoked by inflammation, masses, tumors, infections, hemothorax, and pneumothorax;
lung—embolism; pulmonary infarction; inflammation; asthma; heart—angina (exertional, stable, new-onset, or
unstable); acute myocardial infarctions (MIs); ST-segment elevation MI (STEMI); non–ST-segment elevation
MI (NSTEMI); myocarditis; endocarditis; subacute bacterial endocarditis (SBE); acute rheumatic fever; dysrhythmias
(eg, atrial fibrillation, supraventricular tachycardia [SVT]); valvular abnormalities (eg, mitral valve
prolapse, stenosis); pericardium sensitive (inflammation, infection, and effusion can lead to chest pain); aortic
aneurysm; aortic dissection; mediastinal sources of pain infrequent unless infection present; thyroid enlargement
can cause chest pain
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| Abdomen and GI tract: diaphragm—malformation or eventration; diaphragmatic tics or spasms (hiccups);
esophagus—achalasia; spasm; diverticula; gastroesophageal reflux disease (GERD); abdomen—biliary tract
and gallbladder dysfunction can lead to referred pain from right upper quadrant to chest; liver abscess or inflammation;
splenic flexure syndrome and intestinal problems underneath diaphragm can stimulate chest pain; Fitz-
Hugh-Curtis syndrome (pus formation stimulates chest pain perception)
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| Systemic: thyroid—hypothyroidism and hyperthyroidism can cause problems; anemia
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| Psychogenic: somatoform disorders; anxiety; panic attacks; depression
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| Case presentations: 1) man presents with substernal pressure-type chest pain; severity 6 out of 10; pain lasts 1
min, and timing variable and unpredictable; pain improves with nitroglycerin; patient has unstable angina; patient
should be referred; 2) patient presents with precordial dull chest pain; severity 5 out of 10 and lasts several
minutes; timing variable and unpredictable; pulse irregularity and chest discomfort often present when patient
has lifted or strained; consider SVT and atrial fibrillation; 3) patient presents with precordial chest pain; pain
sharp or “funny”; timing variable; associated with exertion or anxiety; audible midsystolic click; consider mitral
valve prolapse with SVT; consider echocardiography; 4) patient presents with precordial chest pain; severity 6
out of 10; pain presents during event and lasts as long as event; patient has positive family history of sudden
death; exercise provokes discomfort; patient has hypertrophic cardiomyopathy; 5) patient presents with diffuse
sharp pain in various locations in chest; severity 5 to 7 out of 10 and lasts 1 hr to 1 day; onset instantaneous and
occurs with chest wall motion (eg, breathing or coughing); improves with aspirin; patient has pleurisy
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Educational Objectives
| The goal of this program is to educate the listener about atrial fibrillation, syncope, and chest pain. After hearing and
assimilating this program, the participant will be better able to:
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| 1. Choose therapy for patients with atrial fibrillation based on individual findings.
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| 2. Distinguish syncope from seizure.
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| 3. List conditions that can cause vasovagal syncope.
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| 4. Select appropriate tests to diagnose the cause of chest pain.
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| 5. Identify noncardiac causes of chest pain.
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Discussed on This Program
Amiodarone HCl [Cordarone, Pacerone]
Digoxin [Digitek, Lanoxicaps, Lanoxin]
Flecainide acetate [Tambocor]
Nitroglycerin (several trade names and formulations)
Procainamide HCl [Procanbid]
Propafenone HCl [Rythmol, Rythmol SR]
Quinidine gluconate
Sotalol HCl [Betapace, Betapace AF]
Suggested Reading
Amsterdam EA et al: Exercise testing in chest pain units: rationale, implementation, and results. Cardiol Clin
23:503, 2005; Cayley WE Jr: Diagnosing the cause of chest pain. Am Fam Physician 72:2012, 2005; Chung MK et
al: Functional status in rate- versus rhythm-control strategies for atrial fibrillation: results of the Atrial Fibrillation
Follow-Up Investigation of Rhythm Management (AFFIRM) Functional Status Substudy. J Am Coll Cardiol
46:1891, 2005; Dalla Pozza R et al: Impedance cardiography and beat-to-beat blood pressure monitoring in diagnosis
of syncope in long-QT syndrome. Z Kardiol 94:767, 2005; Husser D et al: Evaluation of noncardiac chest pain:
diagnostic approach, coping strategies and quality of life. Eur J Pain 10:51, 2006; Kowacs PA et al: Syncope or epileptic
fits? Some examples of diagnostic confounding factors. Arq Neuropsiquiatr 63:597, 2005; Petrac D et al: Impact
of atrioventricular node ablation and pacing therapy on clinical course in patients with permanent atrial
fibrillation and unstable ventricular tachycardia induced by rapid ventricular response: follow-up study. Croat Med J
46:929, 2005; Ray IB et al: Treating atrial fibrillation. What is the consensus now? Postgrad Med 118:47, 2005;
Strano S et al: Multidisciplinary approach for diagnosing syncope: a retrospective study on 521 outpatients. J Neurol
Neurosurg Psychiatry 76:1597, 2005; Westfall JM: Evaluation of patients with chest pain. Am J Cardiol 93:129,
2004.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. The following
has been disclosed: Dr. Benditt is an investor and consultant for Medtronic Inc. and St. Jude Medical, Inc.
Dr. Benditt spoke in Minneapolis on May 24, 2005, at the 31st Annual Family Medicine Review Update 2005, presented
by the University of Minnesota Medical School. Dr. Crown was recorded in Memphis at the 38th Annual Review
Course for the Family Physician, presented March 14-18, 2005, by the University of Tennessee Health Science Center,
College of Medicine. The Audio-Digest Foundation thanks the speakers and the sponsors for their cooperation in the
production of this program.
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