Diseases of the Myocardium, Acquired Flashcards
What class of medication should you avoid in cocaine toxicity
Beta blockers
Cocaine intoxication clinically presents as a
Cocaine intoxication clinically presents as a sympathomimetic toxidrome that includes tachycardia, hypertension, diaphoresis, chest pain, and mydriasis. Patients may also have hyperthermia and cardiac dysrhythmias.
Cocaine works by
Cocaine exerts its affects by stimulating and blocking reuptake of multiple neurotransmitters (dopamine, epinephrine, norepinephrine, and serotonin). Although many receptors are activated, the most profound effect is the adrenergic stimulation caused by norepinephrine and epinephrine, resulting in vasoconstriction, increased myocardial contractility, increased myocardial oxygen demand, and increased heart rate.
Cocaine-related chest pain ensues as a result of
Cocaine-related chest pain ensues as a result of coronary vasospasm and ischemia due to increased myocardial oxygen demand.
Cocaine-related chest pain is most effectively managed through
benzodiazepines, which will decrease the oxygen demand and sympathetic effects
Should you give aspirin in cocaine induced chest pain
Aspirin should be administered as well since cocaine induces platelet aggregation
Beta-blockers are generally recommended to be avoided in cocaine-related chest pain due to
Beta-blockers are generally recommended to be avoided in cocaine-related chest pain due to the unopposed alpha stimulation that can lead to increased cardiac ischemia. Concern that it can lead to worsening vasoconstriction.
Cocaine effects
True or false: preexistent cardiovascular disease is a prerequisite for cocaine-related myocardial ischemia.
False
Rapid Review: Cocaine Intoxication
Myocarditis
Myocarditis occurs when there is inflammation and necrosis of the myocardium. This typically occurs after an infection and can present with fever, chills, and chest pain. The diagnosis is more likely in a young patient. ECG may demonstrate nonspecific ST segment changes, T wave inversions, and QT prolongation. Echocardiography can demonstrate global hypokinesis. Troponins will be elevated given the damage to the cardiac myocytes. Other tests can include an erythrocyte sedimentation rate or C-reactive protein, serum viral titers, and a cardiovascular MRI. An endomyocardial biopsy is the gold standard to confirm the diagnosis, although it is rarely done. The prognosis is variable in myocarditis, and sudden death is possible even in young and previously healthy patients. The treatment of myocarditis is supportive care, with heart failure medications and antidysrhythmics as needed.
Myocarditis Chart
What is the treatment of pericardial tamponade in a hemodynamically unstable patient?
Pericardiocentesis.
Rapid Review: Myocarditis
What is the biggest risk factor for the development of a left ventricular aneurysm?
Left anterior descending coronary artery infarction
Left ventricular aneurysm
Left ventricular aneurysm formation is a potential complication following a myocardial infarction. Occurring in up to 15% of patients after myocardial infarction, it is characterized by a thinned, focal area of the myocardium and is four times as likely to involve the anterior or apical walls than the inferior or posterior walls. On echocardiogram, the involved segment will appear to paradoxically balloon outward during systole. Electrocardiographic findings include persistent ST segment elevation in the distribution of the recent myocardial infarction. Those at greatest risk for the development of a left ventricular aneurysm include patients with complete occlusion of the left anterior descending artery, delayed or incomplete reperfusion, and absence of collateralization. Treatment of left ventricular aneurysm includes afterload reduction, usually with an angiotensin-converting enzyme inhibitor, and anticoagulation, if there is evidence of significant left ventricular dysfunction or thrombus formation.
Left ventricular aneurysm Chart
Rapid Review: Left ventricular aneurysm
What are the three main complications related to development of a left ventricular aneurysm?
Heart failure, dysrhythmias, and thromboembolic disease.
The use of nitrates is contraindicated in patients who also take
sildenafil
Sildenafil is an
inhibitor of cyclic guanosine monophosphate specific phosphodiesterase type 5. It leads to an increased release of nitric oxide, resulting in smooth muscle relaxation and vasodilation
Sildenafil is commonly used to treat
Erectile dysfunction
Which electrolyte is increased with hydrochlorothiazide use?
Calcium (causing hypercalcemia).
Erectile Dysfunction
Rapid Review: PDE-5 Inhibitors
Which medication is the first line treatment for patients with acute decompensate heart failure
This patient presents with symptoms of acute decompensated heart failure and should be started on nitroglycerin therapy immediately. Patients present with shortness of breath, increased work of breathing, tachycardia, hypoxia, crackles on lung examination, and jugular venous distension. These patients experience acute worsening of left ventricular function and output secondary to a number of mechanisms including increased systemic vascular resistance. Therapy focuses on the reduction of preload to decrease the flow of blood into the lungs and afterload reduction to increase the effectiveness of the left ventricle. Both of these goals can be accomplished through the administration of nitroglycerin. At lower doses, nitroglycerin acts as a peripheral vasodilator and increases venous capacitance leading to decreased preload. At higher doses, nitroglycerin causes arterial vasodilation leading to decreased afterload. Because of its rapid onset of action, nitroglycerin is the first-line medication in patients with acute decompensated heart failure.
Rapid Review: Acute Decompensated Heart Failure
Nitrates chart
What life-threatening toxicity is associated with nitroprusside administration?
Cyanide toxicity.
Which medication has the greatest impact on reducing mortality in patients presenting with acute coronary syndrome?
Aspirin
Aspirin in ACS
Aspirin has been shown to have the greatest effect on reducing mortality in patients with acute coronary syndrome (ACS). Aspirin is an irreversible antiplatelet agent. It inactivates platelets for the life span of the platelet (8–10 days). Studies have demonstrated a 23% reduction in mortality for patients with acute myocardial infarction (AMI) who received aspirin but not thrombolytic therapy. Aspirin also works synergistically with thrombolytics (42% reduction in mortality). Overall, aspirin has a number needed to treat (to prevent death) of 42. Administration of aspirin (chewed and swallowed) is recommended in any patient with suspected ACS.
Which cardiac biomarker has the highest sensitivity and specificity?
Cardiac troponin
Initial Medical Therapy for ACS
Rapid Review: Ischemic Heart Disease
Which medication is contraindicated n an inferior STEMI
Nitroglycerin
Why is nitroglycerin contraindicated in an inferior MI
Patients with an inferior STEMI may have right ventricular infarct and be preload dependent. In a patient with an inferior STEMI, right ventricular infarct is suggested by the presence of ST elevation in lead III larger than that in lead II. A right ventricular infarct can be discovered by performing a right-sided ECG and looking for ST elevation in lead V4R. In these patients, a preload-reducing medication like nitroglycerin can lead to a precipitous drop in blood pressure.
Please interpret this EKG
A right ventricular infarct is suggested by the presence of ST elevation in lead III larger than that in lead II.
Right Ventricular Infarction Chart
Which coronary artery most commonly supplies the inferior wall with blood?
The right coronary artery.
Rapid Review: Inferior ST Elevation Myocardial Infarction
The Sgarbossa ST elevation myocardial infarction (STEMI) criteria
ECG predictors of myocardial infarction are used in the presence of a conduction delay like a left bundle branch block (LBBB). ST segment elevation of at least 1 mm that is concordant with the QRS complex in any lead meets one of the criteria for STEMI. Concordant means that the ST segment and QRS complex have the same direction. The two other criteria for STEMI include concordant ST segment depression of at least 1 mm in lead V1, V2, or V3 and ST segment elevation of at least 5 mm that is discordant with the QRS complex. However, this latter criterion is based on the original Sgarbossa criteria and has been replaced in the modified Sgarbossa criteria with excessive discordance, defined by an ST/S ratio > 0.25. The original Sgarbossa criteria assigned weighted scores to determine the likelihood of STEMI. However, in the modified Sgarbossa criteria, meeting any single criterion yields increased sensitivity without significant loss of specificity in the diagnosis of STEMI in the setting of a conduction delay.
Sgarbossa Criteria
What is the time frame for urgent fibrinolysis in patients with ECG findings of ST elevation myocardial infarction who are not located in a percutaneous coronary intervention (PCI) center and are not able to meet PCI recommended goals?
30 Minutes
Rapid Review: Modified Sgarbossa Criteria
The most common ECG presentation of a posterior STEMI is to only see
the reciprocal changes in the anterior leads.
When horizontal ST depressions are seen in leads V1, V2, and V3 with upright T waves
a posterior ECG should promptly be performed to support the diagnosis
What treatment should be avoided in a right-sided myocardial infarction?
Nitroglycerin
Interpret the EKG, please
Posterior myocardial infarction
Rapid Review: ST Segment Elevation MI
Posterior MI Chart
Hypertrophic Cardiomyopathy Chart
Rapid Review: Hypertrophic Cardiomyopathy
Coronary Anatomy
Please Interpret this EKG
Anterolateral and inferior STEMI.
High Output vs Low Output Heart Failure
What physical exam finding is specific to high-output heart failure?
Bounding pulse with a quick upstroke and a wide pulse pressure.
Rapid Review: High Output Cardiac Failure
What gene mutation is most commonly associated with hypertrophic cardiomyopathy?
Beta-myosin heavy chain.
What is the interpretation of this EKG
Posterior STEMI
Posterior STEMI EKG
Higher Lateral STEMI
Higher Lateral STEMI
What is the most common complication of acute coronary syndrome?
Cardiac Dysrhythmia
What are the classic chest X-ray findings in heart failure?
Kerley B lines and cephalization of flow.
Rapid Review: Acute Decompensated Heart Failure
General Overview of Acute Decompensated Heart Failure
Please Interpret this EKG
Inferior MI
Preload Dependence
Rapid Review: Inferior STEMI
What medication used in the management of acute myocardial infarction activates antithrombin III and inactivates thrombin?
Heparin
What percentage of patients with cocaine chest pain are found to have myocardial injury?
Approximately 6
Treatment Options for Cocaine Induced Chest Pain
Rapid Review: Cocaine Associated Chest Pain
What is the next step in hemodynamic management in patients unresponsive to vasopressors?
Intraaortic Balloon Pump
Ionotropes and Vasopressors
Rapid Review: Cardiogenic Shock
The presence of pneumothorax is identified with which sign on ultrasound?
Lung Point Sign
B lines Ultrasound
B Lines Video Ultrasound
Rapid Review: Ultrasound Pulmonary Edema
What is the name for small, < 2 cm, horizontal lines representing edematous interlobular septa or lymphatic vessels seen in the lower zone periphery on a chest X-ray in patients with congestive heart failure?
Kerley B lines
What is a water hammer pulse?
Bounding pulse with quick upstroke and downstroke.
What respiratory intervention can significantly improve symptoms in acute pulmonary edema?
BiPAP
This CXR is concerning for
Pulmonary Edema
What laboratory test evaluates for a substance released by the ventricles in heart failure?
BNP
In an anterior wall ST elevation myocardial infarction, what decreases the rate of aneurysm development?
Time to revascularlization
Please Interpret this EKG
Concerning for Ventricular Aneurysm
In the setting of ST elevation myocardial infarction, what is the number needed to treat with aspirin to prevent one death
42
Types of Acute Coronary Syndromes
Rapid Review: Chest Pain
What is Brugada syndrome?
Brugada syndrome is a genetic sodium channelopathy that can result in lethal ventricular tachydysrhythmias
Please interpret this EKG
Hypertrophic Cardiomyopathy
Please interpret this EKG
Considered a STEMI equivalent seen with acute left anterior descending artery occlusion, this shows the de Winter pattern with ST depression and peaked T waves in the precordial leads.
Please interpret this EKG
Wellans Syndrome
Wellans Syndrome Chart
Rapid Review: Wellans Syndrome
Besides the history, ECG, age, risk factors, and troponin score, what are two other chest pain scoring tools that are highly sensitive for determining which chest pain patients are appropriate for early discharge from the emergency department?
The North American Chest Pain Rule and the ASPECT Rule.
Heart Score Chart
Rapid Review: Heart Score
Rapid Review: Low Output Heart Failure
BNP Chart
What marker of kidney function is disproportionately elevated in heart failure?
BUN is elevated greater than creatinine
In what leads are the T wave changes of Wellens syndrome most likely to be seen?
V2-V3
What is the pharmacologic treatment of choice for hypertrophic cardiomyopathy?
Beta Blocker
Which analgesic medication should be avoided in patients diagnosed with acute heart failure?
NSAIDS as they can cause sodium and water retention
