Embryology
What do the endocardial cushions give rise to?
Atrial septum, membranous portion of interventricular septum, heart valves
Name at least 3 causes of acute pericarditis
Infection, autoimmune disorders, neoplastic, MI, drug-related, trauma, post-surgical, uremia, radiation, myxedema, idiopathic
What is MOST common channelopathy cause of sudden cardiac death?
Long QT Syndrome
What are the directions of the peaks seen in Lead I and aVF that would cause: normal axis, left axis deviation, right axis deviation, and no man’s land?
Normal: positive, positive
Left: positive, negative
Right: negative, positive
No man’s land: negative, negative
A 56-year-old man is brought to the emergency department 25 minutes after the sudden onset of severe pain in the middle of his chest. He describes the pain as tearing in quality; it radiates to his jaw. He has hypertension. He has smoked one pack of cigarettes daily for the past 25 years. Current medications include enalapril. His blood pressure is 154/95 mm Hg in his right arm and 181/105 mm Hg in his left arm. A CT scan of the chest is shown (on Kayla's laptop). The structure that is damaged in this patient is a derivative of what embryological structure?
Truncus arteriosus (dissection of ascending aorta)
In pericardial effusion, what causes hoarseness?
Compression of recurrent laryngeal nerve
What is pathogenesis of Catecholaminergic VT?
2 mutations identified:
1) Autosomal dominant mutations in ryanodine receptor (calcium channels)
2) Autosomal recessive mutation in calsequestrin 2
These cause diastolic release of calcium into intracellular space; is pro-arrhythmic
NADH inhibits …
AMP stimulates ...
1) citric acid cycle, FA beta-oxidation, pyruvate dehydrogenase
2) glycolysis (via phosphofructo-kinase activation)
Shortly after delivery, a female newborn develops bluish discoloration of the lips, fingers, and toes. She was born at term to a 38-year-old primigravid woman. Pregnancy was complicated by maternal diabetes mellitus. Pulse oximetry on room air shows an oxygen saturation of 81%. Echocardiography shows immediate bifurcation of the vessel arising from the left ventricle; the vessel emerging from the right ventricle gives out coronary, head, and neck vessels. An abnormality in what developmental process most likely accounts for this patient's condition?
Spiraling of aorticopulmonary septum
What is electrical alternans, and what condition is it associated with?
Alternating QRS amplitude that is seen in any or all leads on an ECG with no additional changes to the conduction pathways of the heart. This rhythm is typically associated with pericardial effusion (cardiac tamponade) via the “swinging heart” from the fluid surrounding the heart
YES or NO - can beta blockers be used to treat 1) Congenital long QT syndrome 2) Acquired long QT syndrome 3) Brugada syndrome
1) YES 2) NO 3) NO
What are 2 characteristic ECG findings of Wolff-Parkinson-White syndrome?
Shortened PR interval
Delta wave (slurred upstroke of QRS complex)
A 5-day-old boy is brought to the emergency department by his mother because of a 2-day history of difficulty feeding and multiple episodes of his lips turning blue. He was born at home via spontaneous vaginal delivery and Apgar scores were 7 and 8 at 1 and 5 minutes, respectively. Physical examination shows grunting and moderate intercostal and subcostal retractions. Echocardiography shows a single vessel exiting from the heart. What is likely underlying cause of this patient's condition?
Failure of neural crest cell migration. This leads to a lack of aorticopulmonary septum formation, resulting in a single outflow vessel that receives output from both the right and left ventricles; this condition is known as persistent truncus arteriosus
A 55-year-old man is brought to the emergency department 12 hours after the sudden onset of shortness of breath and substernal chest pain at rest; the pain is increased by inspiration. He has also had a nonproductive cough, fever, and malaise for the past 5 days. He does not smoke or use illicit drugs. His temperature is 38°C (100.4°F), pulse is 125/min, respirations are 32/min, and blood pressure is 85/45 mm Hg. Physical examination shows distended neck veins. Auscultation of the chest discloses bilateral basilar rales and muffled heart sounds. An ECG shows sinus tachycardia, diffuse ST segment elevation, low voltage QRS complexes, and fluctuating R wave amplitude. What is a likely diagnosis?
Cardiac tamponade
A 2-year-old boy is brought to the physician for evaluation of delayed onset of speech. Over the past year, he has also had recurrent dizziness and three episodes of syncope. Examination of the ears shows clear auditory canals and intact tympanic membranes with normal light reflexes. Visual reinforcement audiometry shows bilateral sensorineural deafness. Genetic analysis reveals a mutation in the KCNQ1 gene causing a defect in slow voltage-gated potassium channels. What is an electrocardiogram of this patient most likely to show?
Prolongation of the QT interval
Differentiate between the following First- degree V block, Second-degree AV blocks (Mobitz type I/AV Wenckebach and Mobitz type II), and Third degree AV block
First degree block: delay/prolonged PR interval,. But no failure of conduction
Mobitz type I: gradual prolongation of PR until a P wave fails to conduct
Mobitz type II: abrupt failure of conduction among normal QRS complexes
Third degree block: complete block with no conduction between atria and ventricles; no association between P waves and QRS waves
What are the 4 findings of Tetralogy of Fallot?
Pulmonary infundibular stenosis (narrow pulm trunk and pulm valve → obstruction of outflow from RV)
Ventricular septal defect (atrioventricular opening)
Overriding aorta (aorta is displaced because of VSD; gets both venous and arterial blood)
Hypertrophy of RV (bc of pulmonary infundibular stenosis)
A 63-year-old man who recently immigrated to the United States from Indonesia comes to the physician because of worsening shortness of breath and swollen extremities for the past 3 months. He has had a 4-kg (8.8-lb) weight loss and intermittent fevers over the last 6 months. Examination shows pitting pedal edema and abdominal distension. Abdominal pressure over the right upper quadrant produces persistent distention of the jugular veins. An x-ray of the chest shows cavernous infiltrates in the left and right-upper lobes and a calcified cardiac silhouette. Cardiovascular examination is most likely to show which of the following?
Friction rub
Pericardial knock
Pulsus parvus et tardus
Pericardial knock: high pitched diastolic sound in constrictive pericarditis due to abrupt halting of diastolic ventricular relaxation and filling by the rigid pericardial sac
Classify each as either a gain of function or loss of function mutation, as well as the ion channel that is affected: Long QT 1, Long QT 2, Long QT 3
loss of function mutation in potassium channel gene
loss of function mutation in potassium channel gene
gain of function mutation in sodium channel gene
Which arrhythmia has a characteristic RSR’ wave in V1 and why?
Right bundle branch block. Since electrical conduction starts on the L side of the interventricular septum and goes R, the QRS wave starts normally. However, the delayed conduction input to the RV causes a second, delayed R deflection.