Snapshot A 66-year-old man presents to the emergency deparment with palpitations and lightheadedness. The patient has been experiencing these symptoms for the past few days. He reports mild chest discomfort. Medical history is significant for hypertension, type 2 diabetes mellitus, and rheumatic heart disease. An electrocardiogram is immediately performed, which demonstrates a narrow QRS complex tachyarrhythmia that is irregularly irregular. (Atrial fibrillation) Introduction Aberrant rhythms can occur anywhere along the cardiac conduction system (SA node to a single cardiomyocyte) these aberrant rhythm can originate from the atrium (thus a supraventricular arrhythmia) ventricles Etiology there are a number of causes and they include myocardial infarction cardiac scarring can interrupt the cardiac conduction system atrial stretch alters the cardiac conduction system (e.g., significant mitral stenosis) Symptoms asymptomatic palpitation light headedness syncope sudden cardiac death Atrial Arrhythmias Type Electrocardiogram Findings Treatment Comments Atrial fibrillation A tachyarrhythmia that is irregularly irregular rhythm and has absent P-waves Stable patients rate control e.g., β-blockers and nondihydropyridine calcium channel blocker rhythm control e.g., amiodarone Unstable patients synchronized cardioversion Anticoagulation options include aspirin warfarin new oral anticoagulant (NOAC) e.g., dabigatran Most common type of atrial arrhythmia A dilated left atrium can result in atrial fibrillation e.g., mitral stenosis Can result in a thromboembolic event (e.g., stroke) The ventricular rate is determined by the AV node refractory period Often originates in the pulmonary veins Atrial flutter A tachyarrhythmia with a "sawtooth" appearance Stable patients treat similarly as atrial fibrillation Unstable patients synchronized cardioversion Definitive treatment is with catheter ablation Caused by a re-entrant circuit in the right atrium
QUESTIONS 1 of 3 1 2 3 Previous Next Lab Values Blood Hematologic Cerebrospinal Sweat, Urine, and BMI Blood, Plasma, Serum Reference Range ALT 8-20 U/L Amylase, serum 25-125 U/L AST 8-20 U/L Bilirubin, serum (adult) Total // Direct 0.1-1.0 mg/dL // 0.0-0.3 mg/dL Calcium, serum (Ca2+) 8.4-10.2 mg/dL Cholesterol, serum Rec: < 200 mg/dL Cortisol, serum 0800 h: 5-23 μg/dL //1600 h: 3-15 μg/dL 2000 h: ≤ 50% of 0800 h Creatine kinase, serum Male: 25-90 U/LFemale: 10-70 U/L Creatinine, serum 0.6-1.2 mg/dL Electrolytes, serum Sodium (Na+) 136-145 mEq/L Chloride (Cl-) 95-105 mEq/L Potassium (K+) 3.5-5.0 mEq/L Bicarbonate (HCO3-) 22-28 mEq/L Magnesium (Mg2+) 1.5-2.0 mEq/L Estriol, total, serum (in pregnancy) 24-28 wks // 32-36 wks 30-170 ng/mL // 60-280 ng/mL 28-32 wk // 36-40 wks 40-220 ng/mL // 80-350 ng/mL Ferritin, serum Male: 15-200 ng/mLFemale: 12-150 ng/mL Follicle-stimulating hormone, serum/plasma Male: 4-25 mIU/mL Female: premenopause: 4-30 mIU/mL midcycle peak: 10-90 mIU/mL postmenopause: 40-250 pH 7.35-7.45 PCO2 33-45 mmHg PO2 75-105 mmHg Glucose, serum Fasting: 70-110 mg/dL2-h postprandial:<120 mg/dL Growth hormone - arginine stimulation Fasting: <5 ng/mLProvocative stimuli: > 7ng/mL Immunoglobulins, serum IgA 76-390 mg/dL IgE 0-380 IU/mL IgG 650-1500 mg/dL IgM 40-345 mg/dL Iron 50-170 μg/dL Lactate dehydrogenase, serum 45-90 U/L Luteinizing hormone, serum/plasma Male: 6-23 mIU/mL Female: follicular phase: 5-30 mIU/mL midcycle: 75-150 mIU/mL postmenopause 30-200 mIU/mL Osmolality, serum 275-295 mOsmol/kd H2O Parathyroid hormone, serume, N-terminal 230-630 pg/mL Phosphatase (alkaline), serum (p-NPP at 30° C) 20-70 U/L Phosphorus (inorganic), serum 3.0-4.5 mg/dL Prolactin, serum (hPRL) < 20 ng/mL Proteins, serum Total (recumbent) 6.0-7.8 g/dL Albumin 3.5-5.5 g/dL Globulin 2.3-3.5 g/dL Thyroid-stimulating hormone, serum or plasma .5-5.0 μU/mL Thyroidal iodine (123I) uptake 8%-30% of administered dose/24h Thyroxine (T4), serum 5-12 μg/dL Triglycerides, serum 35-160 mg/dL Triiodothyronine (T3), serum (RIA) 115-190 ng/dL Triiodothyronine (T3) resin uptake 25%-35% Urea nitrogen, serum 7-18 mg/dL Uric acid, serum 3.0-8.2 mg/dL Hematologic Reference Range Bleeding time 2-7 minutes Erythrocyte count Male: 4.3-5.9 million/mm3Female: 3.5-5.5 million mm3 Erythrocyte sedimentation rate (Westergren) Male: 0-15 mm/hFemale: 0-20 mm/h Hematocrit Male: 41%-53%Female: 36%-46% Hemoglobin A1c ≤ 6 % Hemoglobin, blood Male: 13.5-17.5 g/dLFemale: 12.0-16.0 g/dL Hemoglobin, plasma 1-4 mg/dL Leukocyte count and differential Leukocyte count 4,500-11,000/mm3 Segmented neutrophils 54%-62% Bands 3%-5% Eosinophils 1%-3% Basophils 0%-0.75% Lymphocytes 25%-33% Monocytes 3%-7% Mean corpuscular hemoglobin 25.4-34.6 pg/cell Mean corpuscular hemoglobin concentration 31%-36% Hb/cell Mean corpuscular volume 80-100 μm3 Partial thromboplastin time (activated) 25-40 seconds Platelet count 150,000-400,000/mm3 Prothrombin time 11-15 seconds Reticulocyte count 0.5%-1.5% of red cells Thrombin time < 2 seconds deviation from control Volume Plasma Male: 25-43 mL/kgFemale: 28-45 mL/kg Red cell Male: 20-36 mL/kgFemale: 19-31 mL/kg Cerebrospinal Fluid Reference Range Cell count 0-5/mm3 Chloride 118-132 mEq/L Gamma globulin 3%-12% total proteins Glucose 40-70 mg/dL Pressure 70-180 mm H2O Proteins, total < 40 mg/dL Sweat Reference Range Chloride 0-35 mmol/L Urine Calcium 100-300 mg/24 h Chloride Varies with intake Creatinine clearance Male: 97-137 mL/minFemale: 88-128 mL/min Estriol, total (in pregnancy) 30 wks 6-18 mg/24 h 35 wks 9-28 mg/24 h 40 wks 13-42 mg/24 h 17-Hydroxycorticosteroids Male: 3.0-10.0 mg/24 hFemale: 2.0-8.0 mg/24 h 17-Ketosteroids, total Male: 8-20 mg/24 hFemale: 6-15 mg/24 h Osmolality 50-1400 mOsmol/kg H2O Oxalate 8-40 μg/mL Potassium Varies with diet Proteins, total < 150 mg/24 h Sodium Varies with diet Uric acid Varies with diet Body Mass Index (BMI) Adult: 19-25 kg/m2 Calculator ( ) xy AC 7 8 9 Ă· 4 5 6 Ă— 1 2 3 - 0 . = + Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK You have 100% on this question. Just skip this one for now. Take This Question Anyway (M1.CV.13.41) A 28-year-old woman presents to the urgent care center complaining of weakness, confusion, and that her heart is "racing and flopping" in her chest. She has no significant past medical history. She denies any previous episodes of anxiety attacks or heart issues. She smokes 1/2 of a pack of cigarettes per day and is a social drinker. She denies the use of any illicit drugs. She has no known drug allergies, and she does not take any medications on a daily basis. An EKG is ordered and is shown in Figure A. This patient's ventricular contraction rate is determined by which of the following? Review Topic | Tested Concept QID: 100557 FIGURES: A Type & Select Correct Answer 1 SA node refractory period 3% (2/75) 2 AV node refractory period 64% (48/75) 3 Bundle of His conduction speed 15% (11/75) 4 Purkinje fiber conduction speed 8% (6/75) 5 Purkinje fiber refractory period 11% (8/75) L 1 Question Complexity E Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 You have 100% on this question. Just skip this one for now. Take This Question Anyway (M1.CV.12.203) A 60-year-old male presents with palpitations. He reports drinking many glasses of wine over several hours at a family wedding the previous evening. An EKG reveals absent P waves and irregularly irregular rhythm. He does not take any medications. Which is most likely responsible for the patient’s symptoms? Review Topic | Tested Concept QID: 100719 Type & Select Correct Answer 1 Atrial fibrillation 95% (91/96) 2 Transmural myocardial infarction 0% (0/96) 3 Untreated hypertension 0% (0/96) 4 Torsades de pointes 2% (2/96) 5 Ventricular hypertrophy 1% (1/96) L 2 Question Complexity E Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 1
All Videos (2) Podcasts (0) Login to View Community Videos Login to View Community Videos Atrial Flutter Gio Sabal Cardiovascular - Atrial Arrhythmias 8/21/2015 49 views Login to View Community Videos Login to View Community Videos Atrial Fibrillation Gio Sabal Cardiovascular - Atrial Arrhythmias 8/20/2015 46 views