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19-year-old (Female) with Palpitations and Chest Pain

by Mohammad Hajighasemi-Ossareh, MD, MBA

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    00:01 Okay, guys we got a super high-yield topic.

    00:04 Let's get into it.

    00:05 A 19-year-old woman comes to the emergency department with palpitations and chest pain.

    00:12 She admits to taking lithium for bipolar disorder and procainamide for a heart condition but she said she does not remember the details.

    00:21 She ran out of medication two weeks ago and has not been able to restock.

    00:27 Her family history includes bipolar disorder in her mother and maternal aunt but no cardiovascular disease.

    00:36 Her blood pressure 130/90. Her pulse rate is 110 and respirations are 18.

    00:44 There is a wide split in the first heart sound with a holosystolic murmur over the left sternal border.

    00:51 She is visibly cyanotic in the lips and nail beds.

    00:56 Her electrocardiogram shows intermittent superventricular tachycardia with a right bundle branch block.

    01:04 The cardiac enzymes are normal.

    01:07 She is sent for an echocardiogram which shows evidence of dilated right atrium with portions of the tricuspid valve displaced towards the apex.

    01:18 Which of the following medications was the patient exposed to prenatally? Answer choice A: Lithium; Answer choice B: Antidepressant; Answer choice C: Isotretinoin; Answer choice D: Insulin; or Answer choice E: Antihypertensive Now, take a moment to come to the answer by yourself before we go through it together.

    01:47 Okay, guys like I was saying very high-yield topic.

    01:50 Every year, people see a couple of questions regarding this topic on their boards.

    01:55 So, let's go to the question characteristics.

    01:58 Now, this is actually a psychiatry question.

    02:01 We're going to be with the specific medication that's really dealt with by psych but of course, we're dealing with the medical complications of it.

    02:09 This is a two-step question. First, we have to figure out what condition the patient has and then to figure out what medication she was likely exposed to.

    02:20 Of course, the stem is required because we really have to pull a lot of information from the question stem to figure out what was going on.

    02:28 So, we have a young female patient who's presenting to us with the chief complaint of palpitations and chest pain.

    02:36 Now, we're told that she has a history that is significant for bipolar disorder and some type of heart condition and both of these conditions are managed with medications.

    02:50 She takes lithium for her bipolar and procainamide for some type of heart condition which she doesn't know and we're not told about.

    02:59 Now we know the patient has non-compliance with the medication for a least two weeks because she ran out.

    03:04 Looking at her physical exam, we see that she's slightly hypertensive, 130/90.

    03:10 She's tachycardic, 110 and she has cyanosis seen on the lips and the nail bed.

    03:17 On cardiac auscultation, we see a split S1 and what that means is the mitral and tricuspid valves are not closing at the same time.

    03:28 We also have a holosystolic murmur over the left sternal border.

    03:33 Now, this is most likely tricuspid regurgitation because mitral regurg would more commonly be over the apical area.

    03:43 On honor ECG, we see intermittent supraventricular tachycardia in a right bundle branch block and on the echocardiogram, we see a dilated right atrium and the tricuspid valve is displaced towards the apex.

    03:59 Now, very important, a displaced tricuspid valve towards the apex is called Ebstein's anomaly. Outrageously high-yield, that you know this.

    04:09 The treatment for Ebstein's anomaly is procainamide, which is what this patient was taking.

    04:15 The clinical presentation here really is consistent with Ebstein's anomaly.

    04:21 We have an acute arrhythmia which is going to be seen with the underlying Ebstein's anomaly and the condition here is due to a non-compliance with her antiarrhythmic medication, the procainamide.

    04:33 So, the diagnosis here is Ebstein's anomaly. Now we have to figure out what medication given prenatally is associated with it.

    04:42 Now going to the answer choices, right off the bat, you can delete insulin.

    04:46 That is not teratogenic, it is very safe in pregnancy and it's the treatment of choice for diabetes in pregnant patients.

    04:55 Now we're told that the mother has a medical history significant for bipolar disorder.

    05:01 We're told her family history of her mother and aunt have it.

    05:05 Now, we can then eliminate isotretinoin, answer choice C, because that's for acne, not for bipolar and we can also remove answer choice E, antihypertensive.

    05:17 Now, the first-line treatment for bipolar disorder is lithium and we know, and you have to know this, the prenatal exposure to lithium is actually associated with an increased risk of Ebstein's anomaly.

    05:32 So here, the correct answer choice is answer choice A, lithium.

    05:36 So let's go through these answer choices in a bit more detail because this question is this high-yield.

    05:42 Now like we said, the patient's displaying symptoms of Ebstein's anomaly, which is due usually to prenatal lithium exposure.

    05:52 Now, Ebstein's anomaly is characterized by displacement of a portion of a tricuspid valve towards the apex inside the right ventricle.

    06:02 Here we actually call that atrialization of the right ventricle.

    06:07 If you look at our image here, we see a normal heart and then we see Ebstein's anomaly heart in which the tricuspid valve is again displaced towards the apex in the right ventricle and we have atrialization of the right ventricle.

    06:24 Now, this is a congenital malformation that may be manifested, and this important, either at birth or later in life, depending on the extent of the cardiac malformation.

    06:36 Now, that this anomaly can also be related to conduction defects and other congenital malformations of the heart.

    06:43 Now, maternal ingestion of lithium in the first trimester has been related to a 10-fold increase in the likelihood of fetal Ebstein's anomaly.

    06:55 Other mood stabilizers such as valproic acid and carbamazepine are also considered to be teratogenic.

    07:02 Remember that. Now, lithium consumption during pregnancy is also associated with polyhydramnios, nephrogenic diabetes insipidus, thyroid dysfunction, premature delivery, and floppy baby syndrome. All high-yield.

    07:20 You may not get the lithium question, you may not get Ebstein's anomaly because lithium can cause other conditions. Important that you memorize those.

    07:28 Now, the signs and symptoms include here for Ebstein's anomaly are shortness of breath, cyanosis, and palpitation.

    07:36 Patients can also have tachycardia and the ECG may show intermittent supraventricular tachycardia.

    07:42 It can also though show atrial flutter or afib.

    07:47 A significant portion of patients who have Ebstein's anomaly will also have Wolff-Parkinson-White syndrome, when which we have abnormal P waves and prolonged PR intervals that you'll also see.

    08:00 Now, patients may also demonstrate signs of progressive cardiac failure and in severe cases, you will actually have x-ray findings that are going to be supportive of heart failure and then you'll see, on a chest x-ray that is, a right atrium will look dilated to fill the right chest and the entire heart will be what's called box-shaped.

    08:23 Of course, you can get an echocardiogram that can show evidence of dilation of the right atrium and right ventricle along with that displaced tricuspid valve.

    08:33 Now, the treatment for Ebstein's anomaly is either medication or surgery and that really depends on the severity of the condition and any other associated conditions.

    08:44 Now, procainamide is the first line treatment to prevent arrhythmia for patients with Ebstein's anomaly.

    08:51 Important to know: beta blockers, calcium channel blockers in the junction should be avoided to prevent[AV blockade and the activation of the accessory channels that are associated with Wolff-Parkinson-White syndrome which can commonly be seen in patients with Ebstein's anomaly.

    09:10 Now, surgery is reserved for those who have significant complications such as heart failure or exercise intolerance.

    09:20 Now let's look at some of the other answer choices. Now, B, antidepressants.

    09:25 Most antidepressants are actually pretty well-tolerated during pregnancy.

    09:28 The SSRI paroxetine, though, is the exception.

    09:33 It increases the risk of congenital heart defect and of course, all MRI should be avoided.

    09:40 Now, answer choice C, isotretinoin is a vitamin A derivative that has absolutely serious teratogenic effects when taken during pregnancy.

    09:50 Affected infants can have severe craniofacial malformations such as micrognathia, ocular hypertelorism, and a depressed nasal bridge.

    10:01 You can also have conotruncal malformation, transposition of the great vessels, and tetralogy of Fallot and these have all been seen with isotretinoin during pregnancy.

    10:12 NOw, answer choice D, insulin is actually safe during pregnancy and it's the first-line therapy in gestational diabetes.

    10:21 Now, what's important to know though is that the maternal requirement for insulin will fluctuate during pregnancy so you have to monitor the blood levels closely and adjust the insulin dose accordingly.

    10:34 Now, answer choice E, antihypertensives.

    10:39 Now, two medications are recommended for patients with hypertension while pregnant: methyldopa and hydralazine.

    10:47 However, methyldopa is associated with anemia and hydralazine increases the risk of developing drug-induced lupus erythematosus.

    10:57 Magnesium is another medication we can actually use and it's actually useful in cases of preeclampsia or eclampsia but other antihypertensive medications should really be avoided in pregnancy and the one you have to absolutely avoid are ACE inhibitors because this class of antihypertensive poses the greatest risk of teratogenicity during pregnancy.

    11:22 You can have intrauterine growth restriction, renal failure, oligohydramnios, pulmonary hypoplasia, patent ductus arteriosus, and a hypoplastic calvarium as some of the congenital malformations that can be seen in taking in ACE inhibitor during pregnancy.

    11:41 Even worse, stillbirths and neonatal deaths have been reported with them taking ACE inhibitors during pregnancy.

    11:49 Now, let's review some high-yield facts of Ebstein's anomaly.

    11:54 Now, this is a congenital heart defect.

    11:56 You will have a displacement of the tricuspid valve towards the apex.

    12:01 The cause really though, is unknown.

    12:04 We know it's associated with prenatal exposure to lithium but why you have a displacement of the tricuspid valve is really quite unknown.

    12:12 The main complications are arrhythmias and associated symptoms including stroke and the treatment is an antiarrhythmic medication.

    12:21 Procainamide being our first agent of choice and surgery in severe cases.


    About the Lecture

    The lecture 19-year-old (Female) with Palpitations and Chest Pain by Mohammad Hajighasemi-Ossareh, MD, MBA is from the course Qbank Walkthrough USMLE Step 2 Tutorials.


    Author of lecture 19-year-old (Female) with Palpitations and Chest Pain

     Mohammad Hajighasemi-Ossareh, MD, MBA

    Mohammad Hajighasemi-Ossareh, MD, MBA


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