ATRIAL FIBRILLATION CASE
Mr. Fred Ib is a 68 year old caucasian male who presents to the IMC with a chief complaint of “my heart is racing”. He has felt more short of breath over the past few weeks, especially with exertion. He denies chest pain but does have feelings of fatigue and brief periods of "dizziness" with the heart sensations. They usually last only a few minutes but are becoming more frequent and are occurring daily.
Past Medical History: HTN, DM Type 2, OSA on CPAP, Dyslipidemiadyslipidemia, Stroke stroke (11 years ago), nonobstructive CAD, COPD, chronic LLE wound
Past Surgical History: Cardiac catheterization (9 years ago), inguinal hernia surgery repair (23 years ago), wrist surgery (20 years ago)
Allergies: NKDA
Medications: Metformin 1000mg BID, Atorvastatin 40mg at bedtime, Losartan 100mg daily, HCTZ 25mg daily, ASA 81mg daily, Clonidine 0.3mg BID, Albuterol 90mcg/inh 2puffs q4hrs PRN shortness of breath
Social History: Tobacco use for 3 years but quit in his 20s; Denies ETOH or illicit drugs. Married. Works for the department of transportation at a rest stop 4 days a week. Denies caffeine. He does not have insurance.
Family History: Mother - HTN, Alzheimers; Father - CAD, HTN
ROS: About the same time his chronic leg wound became infected and he was on an antibiotic (TMP-SMX x10 days) but that seems to be getting better; he was using occasional over-the-counter ibuprofen for the leg pains.
He denies any headache, cough, wheeze, abdominal pain, n/v/d/c, melena, hematochezia, dysuria, hematuria, rash, seizure, or numbness or weakness in arms or legs.
Preventative: Colonoscopy - incomplete prep and has not called to reschedule as "life is too busy"; AAA screening negative (3 years ago). Refused PSA. HIV and Hepatitis C screening was negative.
Vaccinations: He has received prevnar, pneumovax (after age 65), influenza, Tdap and zostavax
Physical Examination:
Vitals: HR 105, BP 146/88, Resp 14, Pulse Ox 98%RA, Ht 68.5 in, Wt 295 lbs, BMI 44.2 kg/m2
General: Alert & Oriented x3, NAD, Pleasant, Obese
HEENT: PERRL, EOMI, moist mucous membranes, unable to visualize posterior pharynx, no oral lesions noted; turbinates pink
Neck: Supple, no JVD, no lymphadenopathy, no thyromegaly
Heart: Irregular S1S2, no murmur, gallop, or rub
Lungs: clear to auscultation bilaterally but diminished; no wheeze, rhonchi, or crackles
Abdomen: Soft, Obese, + BS, NT/ND, no mass, hernia, or bruit
Lower legs: 1+ LE edema bilaterally, no clubbing, LLE wound with dressing and no signs of infection underlying
Neurologic: CN II-XII grossly intact, nonfocal
Vascular: PPP
Please Use the 2014 Atrial Fibrillation (AF) Guidelines to answer the following questions
http://circ.ahajournals.org/content/early/2014/04/10/CIR.0000000000000040.citation
You order an in-house EKG since the patient has been having symptoms and his heart rate is fast. While waiting for the EKG, you suspect atrial fibrillation so you pull up the guidelines.
1. How is atrial fibrillation classified? What category would our patient be classified as? (pg. 10, tbl. 3)
2. In AF, what are the proposed atrial abnormalities that alter atrial tissue to promote the abnormal impulse formation and/or propagation? (pg. 11, also fig. 1)
3. What risk factors contribute to AF? Which of these does our patient have? (pgs. 11-12, fig. 1 & tbl. 4)
The nurse brings you the EKG and upon review you note it is an irregular rhythm with no p-waves identifiable at a rate of 120 and normal axis. His repeat BP is 142/80. There are no q waves, ST-T wave changes, or wide QRS complexes although there are high voltage QRS complexes in the precordial leads consistent electrically with LVH. You diagnose atrial fibrillation.
4. What EKG, echocardiographic, & biochemical markers are associated with increased risk of AF? (pg. 12, tbl. 4; pg. 46, appx. 3)
5. What laboratory tests or additional studies are indicated at this time? (pgs. 46-47, appx. 3)
Upon returning to the exam room, you discuss with Mr. F. Ib about controlling how fast his heart beats and explain that this is likely contributing to the symptoms he has been experiencing.
6. What medications are recommended to control the ventricular rate in AF? (pg. 17, also tbls. 8 & 9)
• How do you determine if his heart rate is adequately controlled and when is it assessed? (pg. 17, also tbl. 8)
• What is the heart rate goal for our patient as he is having symptoms more frequently? What is the heart rate goal for those who are asymptomatic? (pg. 17, also tbl. 8)
Mr. F. Ib has no signs or symptoms of ischemia or heart failure with no ischemic EKG changes and he is hemodynamically stable. You write a script for metoprolol 25mg BID and tell him after an initial work-up there are more treatment decisions that need to be discussed. You then order the appropriate labs and imaging and plan for a close follow-up appointment.
At his follow-up visit 8 days later, the patient is feeling much better after starting the metoprolol as prescribed. His BP is 132/80 and his HR is 60 and irregular. Upon review the patient's CBC, BMP, hepatic panel, and TSH are all within normal limits. His CXR shows some cardiomegaly but clear lung fields and normal pulmonary vasculature. His trans-thoracic 2D echocardiogram has normal LVSF with an EF of 65%, a mildly enlarged left atrium, mild-moderate RV dysfunction, and mild concentric LV hypertrophy; no other abnormalities or valvular dysfunction is noted. It is noted that the heart appears to be in atrial fibrillation on imaging.
After a thorough discussion with Mr. F. Ib about anticoagulation, explaining the benefits and risks of treatment options and assessing his preferences, you both agree to start anticoagulation. He voices that he fully understands the risk of stroke without treatment and bleeding with anticoagulation. He laughs and says "No contact sports or bronco riding for me, and I don't own an ATV".
7. What is his CHA2DS2-VASc score? What is his risk of stroke per year? (pgs. 15-16, tbl. 6)
8. What are the reasons you should start anticoagulation? (pg. 13, also tbl. 5)
• What anticoagulation options are available for this patient? (pg. 13, also tbl. 5)
• Should you start anticoagulation now? Do you need to bridge with heparin? (pg. 13, also tbl 5)
• Are there any cautions or contraindications to using some of the treatment agents? How often does this need monitoring? (pgs. 13-14, also tbls. 5 & 7)
• What if the patient had a recent cardiac stent placed, would you use dual anti-platelet therapy plus anticoagulation? (pg. 14, also tbl. 5)
The patient wants to obtain insurance so he can take one of the direct oral anticoagulants. You recommend a visit with the social worker. For now he will begin warfarin and will come back in a week to check his INR. He repeats that his goal INR is 2-3. Mr. F. Ib is satisfied with his care.
9. What would you advise the patient regarding his occasional ibuprofen? What about antibiotics in the future? (Not in guideline, discuss with pharmacist for specific medications that are high-risk for interactions with warfarin)
Bonus Questions
10. What treatment is indicated if the patient was hemodynamically unstable? (pgs. 17-18, also tbl. 8)
• When would a rhythm control strategy with direct-current cardioversion be indicated? (pg. 20, also tbl. 10)
• What should be done before initiating antiarrhythmic therapy? (pg. 21)
• When do you anticoagulate and what is the duration when performing cardioversion? (pgs. 19-20, also tbl. 10)
• How do you anticoagulate if a trans-esophageal echocardiogram (TEE) is performed? (pg. 19, also tbl. 10)
11. Which antiarrhythmics are used for pharmacologic cardioversion of AF? (pg. 20, tbl. 10; pg. 25 fig. 2)
• What antiarrhythmics are used to maintain sinus rhythm as an outpatient and what are their contraindications? (pgs. 21-22, also tbl. 11; pg. 25 fig. 2)
• When is AF catheter ablation recommended? (pg. 24)
• When would a MAZE surgery be indicated? (pg. 25)
For specifics patient group recommendations: HOCM, ACS, Hyperthyroidism, Pulmonary disease, WPW, HF, Familial, Post CABG (pg. 26-31)
• Atrial Fibrillation case by Jason Kunz D.O., Updated 6-2015;
• Thanks to Drs. Rex Wilford D.O. & Ron Jones M.D