Summary Notes - Cardiology - Maggie's Med Notes

Estimated reading time for this document is 29 minutes. # EKG *See notes from the [[02 - Introduction to ECG|ECG lecture]] for more details.* #### Lead Layout ![[12-Lead ECG Layout.png]] #### Heart Rate > [!multi-column] >>[!blank] >>> [!ECG] Box Method >>> - 300 - 150 - 100 - 75 - 60 - 50 >> >>>[!blank] >> >> >>>[!ECG] Count Method >>>- \# of QRS complexes in 10-seconds x 6 > >>[!blank] >>![[ECG box method of calculating heart rate.png]] #### Rhythm > [!multi-column] >> [!check] Sinus Rhythm >> - ***P wave before every QRS complex*** >> - upright P wave in Lead II >> - biphasic P wave in Lead V1 >> >>![[normal sinus rhythm.png]] > >> [!fail] Not Sinus Rhythm >> - indicates the presence of an [[arrhythmias|arrhythmia]] (see [[Summary Notes - Cardiology#ARRHYTHMIAS|here]] for an overview of the different types) >> - ***inconsistent R-R interval*** >> >>![[arrhythmia.png]] #### Intervals > [!multi-column] >> [!ECG|wide-5] [[PR Interval]] >> From the *beginning* of the P-wave to the *beginning* of the QRS complex. Represents the ***[[atrioventricular node|AV node]] delay***. >> >> Should *not* be longer than 1 large box (120-200 ms). >> - 🐺⚪️ **[[short PR interval|< 120 ms]]** → impulse bypasses [[atrioventricular node|AV node]] (e.g., [[Wolff-Parkinson-White syndrome]]) >> - 1️⃣⛔️ **[[long PR interval|over 200 ms]]** → [[1st degree atrioventricular block]] > >>[!blank] >>![[PR interval.png]] > [!blank] >[!multi-column] >> [!ECG|wide-5] [[QRS Complex]] >>From the *beginning* of the Q wave to the *end* of the S wave. Represents ***ventricular depolarization***. >> >> Should *not* be longer than ½ large box (i.e., 3 small boxes; 80-120 ms). A **[[broad QRS complex]]** (i.e., > 120 ms) indicates: >> - disruption of electrical conduction system (e.g., [[left bundle branch block|LBBB]] or [[right bundle branch block|RBBB]]) >> - [[ventricular tachycardia]] >> - [[hyperkalemia]] >> - [[tricyclic antidepressant overdose]] > >>[!blank] >>![[QRS complex.png]] > [!blank] >[!multi-column] >> [!ECG|wide-3] [[QT Interval]] >> From the *beginning* of the Q wave to the *end* of the T wave. Represents time taken for ***ventricular depolarization and repolarization***. >> >> > [!multi-column] >> >>[!blank] >> >> Should *not* be more than ½ R-R interval. A **[[long QT syndrome|long QT interval]]** can indicate: >> >> - [[hypokalemia]] >> >> - [[hypomagnesemia]] >> >> - [[hypocalcemia]] >> >> - [[coronary artery disease|myocardial ischemia]] >> >> - [[long QT syndrome]] >> >> - some medications/drugs ([[anti-ABCDEF]]) >> > >> >>[!caution] Torsades de Pointes >> >>💀 Prolongation of the QT interval can cause **[[torsades de pointes]]**, an irregular rhythm that can lead to sudden death. >> >>![[torsades de pointes.png]] > >>[!blank] >>![[QT interval.png]] #### Axis > [!multi-column] >> [!check] Normal Axis >> - Lead I = positive (L👍) >> - Lead aVF = positive (R👍) > >> [!ECG] [[Left Axis Deviation]] >> - Lead I = positive (L👍) >> - Lead aVF = negative (R👎) > >> [!ECG] [[Right Axis Deviation]] >> - Lead I = negative (L👎) >> - Lead aVF = positive (R👍) # ARRHYTHMIAS ### 📉 Bradycardia **[[Bradycardia]]** is defined as a heart rate < 60 bpm (i.e., 5 big boxes on ECG). #### SA Node Dysfunction Bradycardia can be due to problems with the heart's pacemaker - the [[sinoatrial node|SA node]]. > [!multi-column] > >[!ECG] [[Sinus Bradycardia]] > >- 🐢 slow rate (< 60 bpm) > >- ✅ normal sinus rhythm > > > >![[sinus bradycardia.png]] > >>[!ECG] [[Tachycardia-Bradycardia Syndrome]] >>- 📉 tachycardia → long pause → bradycardia >>- ⚡️ abnormal conduction in atrial tissue >> >>![[tachycardia-bradycardia syndrome.png]] > [!blank] >[!multi-column] > >>[!ECG] [[Chronotropic Incompetence]] >>- 🏃‍♂️ rate does not ↑ during exertion >>- 💉 [[sinoatrial node|SA node]] is insensitive to [[epinephrine]] >> >>![[chronotropic incompetence.png]] > >>[!blank] >>>[!ECG] [[Sinoatrial Arrest]] >>>- 🛑 [[sinoatrial node|SA node]] pauses or stops (see below) >>>- 🫡 another region of the heart must take over as pacemaker (see [[hierarchy of cardiac automaticity.png|here]] for hierarchy of alternative pacemakers) >> >>>[!blank] >> >>>[!multi-column] >>> >>>>[!ECG] **Sinus Pause** >>>> - no electrical activity for < 3 seconds >>>> >>>>![[sinus pause.png]] >>> >>>> [!ECG] **Sinus Arrest** >>>> - no electrical activity for > 3 seconds >>>> >>>> ![[sinus arrest.png]] #### Heart Blocks Bradycardia can also be due to problems with the heart's conducting system. ###### Atrioventricular Blocks AV blocks cause problems with the electrical conduction **between** the [[atria]] and the [[ventricles]]. >[!ECG] [[1st degree atrioventricular block|1st Degree AV Block]] >>[!multi-column] >>>[!blank] >>>- prolonged AV node delay (i.e., [[long PR interval]] > 200 ms or 1 big block) >>>- asymptomatic & no treatment required >>> >>>![[AV block poem - 1st degree.png]] >> >>>[!blank] >>>![[AV blocks - 1st degree.png]] > [!blank] > [!multi-column] > > >[!ECG] [[Mobitz I|2nd Degree AV Block - Type I]] > >>[!multi-column] > >>>[!blank|wide-3] > >>>- increasingly [[long PR interval]] until there is a QRS omission > >>>- block occurs *AT the AV node* > >>>- relatively benign & no treatment required > >>> > >>>![[AV block poem - Mobitz I.png]] > >>> > >>>![[AV blocks - Mobitz I.png]] > > >[!ECG] [[Mobitz II|2nd Degree AV Block - Type II]] > >>[!multi-column] > >>>[!blank|wide-3] > >>>- consistent [[PR interval]], but some P waves don't conduct > >>>- block occurs *BELOW the AV node* > >>>- ⚡️ treat with a pacemaker > >>> > >>>![[AV block poem - Mobitz II.png]] > >>> > >>>![[AV blocks - Mobitz II.png]] > [!blank] >[!ECG] [[3rd degree atrioventricular block|3rd Degree AV Block]] >>[!multi-column] >>>[!blank] >>>- AV dissociation; P waves and QRS complexes are NOT in sync >>>- block occurs *BELOW the AV node* >>>- ⚡️ treat with a pacemaker >>> >>>![[AV block poem - 3rd degree.png]] >> >>>[!blank] >>>![[AV blocks - 3rd degree.png]] ###### Bundle Branch Blocks The [[bundle branch blocks]] cause problems with conduction **within** the [[ventricles]]. The WiLLiaM MaRRoW mnemonic can be used to quickly recognize L and R BBBs by looking at V1 and V6. - middle letters = L (left) or R (right) - 1st and last letters = ECG features >[!multi-column] > >>[!ECG] WiLLiaM = [[left bundle branch block|Left BBB]] >>- V1 = **"W"** >>- V6 = **"M"** >> >>![[LBBB.png]] > >>[!ECG] MaRRoW = [[right bundle branch block|Right BBB]] >>- V1 = **"M"** >>- V6 = **"W"** >> >>![[RBBB.png]] ### 📈 Tachycardia **[[Tachycardia]]** is defined as heart rate > 100 bpm (i.e., 3 big boxes on ECG). #### Supraventricular Tachycardia (SVT) **[[Supraventricular tachycardia]]** (aka "**narrow-complex tachycardia**") has QRS complexes less than 120 ms wide (i.e., 3 small boxes on ECG). To distinguish between different types of SVT, block the [[atrioventricular node|AV node]] to see if the P-waves are still abnormal: - 💊 [[adenosine]] - 🏋️ Valsalva maneuver (or other vagal maneuvers, such as carotid [[carotid sinus massage]]) ###### AV Node Independent (A Flutter & A Fib) >[!multi-column] >> [!blank] >>These arrhythmias will continue even if the [[atrioventricular node|AV node]] is blocked. >> >> >[!treatment] Preventing Stroke >> >With [[atrial flutter|a flutter]] and [[atrial fibrillation|a fib]], blood can pool in the [[atria]] (especially the auricles), which can cause clotting. >> >- 🩸 always give [[anticoagulants]] to prevent [[stroke]] > > > [!ECG|wide-2] [[Atrial Flutter]] > > - 🪚 sawtooth pattern > > > > ![[atrial flutter.png]] > [!blank] > [!multi-column] > >[!white] CHADS Score > >- 📝 [[CHADS Score]] helps determine stroke risk in [[atrial fibrillation|AFib]] > > ![[CHADS-VASc.png]] > > >[!ECG|wide-2] [[Atrial Fibrillation]] > > - 📉 rate control with [[beta-blockers]], [[calcium channel blockers]], or [[digoxin]] > > - ⚡️ **0-48 hours**: can do [[electrical cardioversion]] to return to sinus rhythm > > - 💊 **48+ hours**: 📉 rate control and 🩸 [[anticoagulants]] > > > > ![[atrial fibrillation.png]] > [!blank] ###### AV Node Dependent (AVNRT & AVRT) These arrhythmias will stop if the AV node is blocked. > [!white] [[AV Nodal Reentrant Tachycardia]] > - caused by re-entry circuit around the [[atrioventricular node|AV node]] > - can be triggered by lifting heavy items, bending forward, or drinking cold water > - more common in women > > > [!multi-column] > >> [!ECG|wide-2] **Slow-Fast** > >> - anterograde = **slow AV nodal pathway** > >> - retrograde = **fast AV nodal pathway** > >> - (⭐️) most common (80-90% of AVNRTs) > >> > >>![[slow-fast AVNRT.jpg]] > > > > > [!blank] > > >> [!ECG] **Fast-Slow** > > >> - anterograde = **fast AV nodal pathway** > > >> - retrograde = **slow AV nodal pathway** > > >> - uncommon (10% of AVNRTs) > > >> > > >>![[fast-slow AVNRT.jpg]] > > > > > >>[!blank] > > > > > >> [!ECG] **Slow-Slow** > > >> - anterograde = **slow AV nodal pathway** > > >> - retrograde = **slow left atrial fibres approaching the [[AV node]]** > > >> - least common (1-5% of AVNRTs) > > >> > > >>![[slow-slow AVNRT.jpg]] > [!white] [[AV Reentrant Tachycardia]] > - caused by an accessory pathway > - most commonly seen with [[Wolff-Parkinson-White syndrome]] > > > [!multi-column] > >> [!ECG] **Orthodromic Conduction** > >> Conduction occurs through the AV node (i.e., **anterograde**) > >> - *narrow-complex* > >> - appears similar to [[AV nodal reentrant tachycardia|AVNRT]], but the RP interval is usually longer (> 70 ms) > > > >> [!ECG] **Antidromic Conduction** > >> Conduction occurs through the accessory pathway (i.e., **retrograde**) > >> - *broad-complex* > >> - uncommon (< 10% of AVRTs) > >> - can be difficult to distinguish from [[ventricular tachycardia]] (if any doubt, assume VT and treat accordingly) ![[orthodromic and antidromic AVRT.png]] #### Ventricular Tachycardia **[[Ventricular tachycardia]]** (aka "**broad-complex tachycardia**") has [[broad QRS complex|wide QRS complexes]] (over 120 ms wide; 3 small boxed on ECG). - 💀 can cause death if it isn't stopped > [!multi-column] >> [!ECG] [[monomorphic ventricular tachycardia|Monomorphic VT]] >> - 👯‍♀️ all QRS complexes look the same >> - 🧐 looks similar to [[supraventricular tachycardia|SVT]] in patient with [[bundle branch blocks]] >> >> ![[monomorphic ventricular tachycardia.png]] > >> [!ECG] [[polymorphic ventricular tachycardia|Polymorphic VT]] >> - 👬 QRS complexes do NOT look the same >> - ∿ [[torsades de pointes]] is one type >> >>![[polymorphic ventricular tachycardia.png]] > >>[!ECG] [[Ventricular Fibrillation]] >>- 🤪 completely disorganized rhythm >> >>![[ventricular fibrillation EKG.png]] ### 🧠 Arrhythmia Mind Map https://drive.google.com/file/d/1mIFLPKqDCTscJEtDhLLwy_m9OBs75IIe/view?usp=drive_link ![[Arrhythmias Canvas.png]] # CARDIAC MURMURS #### Heart Sounds > [!multi-column] >> [!blank] >> - S3 = volume loaded ventricle ("slosh-ing-IN") > >> [!blank] >> <audio controls= "click" name="media"><source src="https://depts.washington.edu/physdx/audio/s31.mp3" type="audio/mpeg"></audio> > [!multi-column] >> [!blank] >> - S4 = stiff/hypertrophic ventricle ("a-stiff-wall") > >> [!blank] >> <audio controls="click" name="media"><source src="https://depts.washington.edu/physdx/audio/s41.mp3" type="audio/mpeg"></audio> ### 🧠 Cardiac Murmurs Mind Map https://drive.google.com/file/d/1yn6vgKzeGDs7g94nsbOy5MxRJLnUeclH/view?usp=drive_link ![[cardiac murmurs framework.png]] #### Aortic Stenosis ([[aortic stenosis|AS]]) Stiffening of the [[aortic valve]] that obstructs blood flow from the [[left ventricle]] to the body via the [[aorta]]. > [!multi-column] >> [!ECG|wide-5] Clinical Features >> - 🩺 [[mid-systolic murmur]] best heard at the aorta; radiates to the carotids or the apex >> - 🐢 [[pulsus parvus et tardus]] (weak & slow pulse) >> - 😭 **SAD triad** = (S) [[syncope]], (A) [[angina]], (D) [[dyspnea]] >> - 💕 often due to a [[bicuspid aortic valve]] >> - 🩸 can cause [[microangiopathic hemolytic anemia|MAHAs]] (RBCs get damaged as they turbulently squeeze through small opening) >> - 🫀 can lead to [[ventricular hypertrophy]] (LV needs ↑ force against the valve) > >> [!treatment] >> *Treatment is only indicated in SYMPTOMATIC patients*. >> - 🧍‍♂️ exercise restriction >> - 🔪 [[heart valve replacement]] surgery #### Aortic Regurgitation ([[aortic regurgitation|AR]]) Backward flow of blood from the [[aorta]] to the [[left ventricle]] due to weakening of the [[aortic valve]]. > [!multi-column] >> [!ECG|wide-5] Clinical Features >> - 🩺 [[early diastolic murmur]] best heard at Erb's point at the **end of expiration** while the patient is sitting up and leaning forward >> - 💕 often due to a [[bicuspid aortic valve]] >> - 🫁 blood backs up to the lungs, causing [[pulmonary edema]] and [[dyspnea]] >> - 🫀 [[dilated cardiomyopathy|left ventricular dilation]] due to ↑ blood volume → [[left ventricular hypertrophy]] develops to normalize wall stress >> - 🥶 [[cyanosis]] due to ↓ perfusion throughout the body > >> [!treatment] >> *Surgery is indicated in SYMPTOMATIC patients who have LV failure* >> - 🔪 [[valvuloplasty]] or [[heart valve replacement]] surgery #### Mitral Stenosis ([[mitral stenosis|MS]]) Stiffening of the [[mitral valve]], causing blood to back up throughout the heart and pulmonary system. > [!multi-column] >> [!ECG] Clinical Features >> - 🩺 [[late diastolic murmur]] best heard at the apex, with an #Cardio/sounds/opening-snap >> - 🦠 most commonly caused by [[rheumatic heart disease]] following infection with [[Streptococcus pyogenes|Group A strep]] >> - 🧓🏻 can also be caused by calcification (e.g., old age) >> - 😮‍💨 exertional [[dyspnea]] (most common symptom) >> - 🫁 [[pulmonary edema]] >> - 🫀 [[heart failure]] > >> [!treatment] >> *Treatment aims to ↓ BP and surgical repair (preferred) or replacement of the valve*. >> - 🥗 low salt diet & 🏃‍♂️ ↑ exercise >> - 💊 [[ACE inhibitors]] to control [[essential hypertension]] (MR can be exacerbated with ↑ afterload) >> - 💊 [[diuretics]] for volume overload >> - 💊 treat [[atrial fibrillation]] (if present) with [[anticoagulants]] and [[beta-blockers]]/[[calcium channel blockers]] >> - 🔪 [[valvuloplasty]] or [[heart valve replacement|mitral valve replacement]] #### Mitral Regurgitation ([[mitral regurgitation|MR]]) Backward flow of blood from the [[left ventricle]] to the [[left atrium]] when the LV contracts. > [!multi-column] >> [!ECG] Clinical Features >> - 🩺 [[holosystolic murmur]], best heard when lying on left side >> - 🫁 [[pulmonary edema]] >> - 🫀 [[heart failure]] >> - ⚠️ acute MR can cause ruptured [[chordae tendinae]], because the heart has not had time to compensate for the prolapse > >> [!treatment|wide-3] >> *Treatment aims to ↓ BP and surgical repair (preferred) or replacement of the valve*. >> - 🥗 low salt diet & 🏃‍♂️ ↑ exercise >> - 💊 [[ACE inhibitors]] to control [[essential hypertension]] (MR can be exacerbated with ↑ afterload) >> - 💊 [[diuretics]] for volume overload >> - 💊 treat [[atrial fibrillation]] (if present) with [[anticoagulants]] and [[beta-blockers]]/[[calcium channel blockers]] >> - 🔪 [[valvuloplasty]] or [[heart valve replacement|mitral valve replacement]] # CARDIAC CYCLE > [!multi-column] >> [!blank] >> > [!multi-column] >> >> [!red] Step ①: Atrial Systole (Contraction) >> >> - P wave on EKG >> >> - ↑↑ atrial pressure >> >> - ↑ ventricular volume ("atrial kick") >> > >> >> [!pink] Step ②: Isovolumetric Contraction >> >> - QRS complex on EKG >> >> - S1 heart sound ([[atrioventricular valves]] close) >> >> - ALL VALVES ARE CLOSED >> >> - ↑↑ ventricular pressure >> >> - end-diastolic volume (normal ~120 mL) >> > >> >> [!orange] Step ③: Rapid Ejection >> >> - [[semilunar valves]] open >> >> - ↑↑ aortic pressure >> >> - ↓↓ ventricular volume >> > >> >> [!yellow] Step ④: Reduced Ejection >> >> - T wave on EKG >> >> - ↑↑ atrial volume - atrial diastole (filling) >> >> - end-systolic volume (normal ~50 mL) >> > > >> [!blank] >> ![[pressure-volume loop.png]] >[!multi-column] >> [!green] Step ⑤: Isovolumetric Relaxation >> - ↓↓ ventricular pressure >> - S2 heart sound ([[semilunar valves]] close) > >> [!blue] Step ⑥: Rapid Ventricular Filling >> - [[atrioventricular valves]] open >> - ↑↑ ventricular volume >> - S3 heart sound (turbulent ventricular filling) > >> [!purple] Step ⑦: Reduced Ventricular Filling >> - ↑ ventricular volume >> - ↑ ventricular pressure # CARDIAC OUTPUT $\huge cardiac\ output = heart\ rate \times stroke\ volume $ #### Heart Rate - determined by the pacemaker (usually the [[SA node]]) - ↑ by sympathetic activation (norepinephrine @ β1 adrenergic receptors) - ↑ HR = [[tachycardia]] - ↓ by tonic parasympathetic activity (acetylcholine @ muscarinic ACh receptors) - ↓ HR = [[bradycardia]] #### Stroke Volume > [!multi-column] >> [!blank] >> ###### PRELOAD >> - ***end-diastolic volume*** >> - ↑ by vasoconstriction, atrial contraction, >> - chronic ↑ in preload will lead to *eccentric* hypertrophy >> - ↓ by ventricular stiffness, hypovolemia, intrathoracic pressure (RV preload only) > >> [!blank] >> ###### AFTERLOAD >> - ***pressure ventricle needs to generate to pump blood out of it*** >> - ↑ by larger radius (dilated ventricle), [[hypertension]], [[aortic stenosis]] >> - chronic ↑ in afterload will lead to *concentric* hypertrophy > >> [!blank] >> ###### CONTRACTILITY >> - ***ability for muscle cells to shorten in length*** >> - INDEPENDENT of preload and afterload >> - ↑ by sympathetic activation (norepinephrine @ β1 adrenergic receptors) >> - ↓ by tonic parasympathetic activity (acetylcholine @ muscarinic ACh receptors) # CARDIAC DRUGS #### 💊 [[ACE inhibitors]] ("---pril" drugs) > [!blank] > > [!multi-column] > >>[!drugs] ACE Inhibitor Examples > >>- [[enalapril]] > >>- [[ramipril]] > >>- [[lisinopril]] > > > > > [!blank|wide-5] > > > - ↑ parasympathetic activity > > > - ↑ acetylcholine (prevent its degradation) > > > - ↑ bradykinin (vasodilator) - might cause side effects like cough and angioedema > [!multi-column] >> [!check] Indications >> - (⭐️) [[essential hypertension]] >> - [[systolic heart failure|HFrEF]] >> - post [[myocardial infarction]] (↓ afterload and help with cardiac remodelling) >> - [[diabetic nephropathy]] (↓ BP at the glomerulus) > >> [!caution] Contraindications >> - [[hyperkalemia]] >> - patients who already have dry cough >> - [[hypotension]] >> - worsening kidney function >> - [[pregnancy]] #### 💊 [[angiotensin receptor blockers|Angiotensin Receptor Blockers]] ("---sartan" drugs) > [!blank] > > [!multi-column] > >> [!drugs] ARB Examples > >> - [[valsartan]] > >> - [[losartan]] > > > >> [!blank|wide-5] > >> - ↑ parasympathetic activity > >> - similar to [[ACE inhibitors]] (no cough side effect though) > [!multi-column] >> [!check|wide-3] Indications >> - (⭐️) [[essential hypertension]] >> - [[systolic heart failure|HFrEF]] >> - post [[myocardial infarction]] (↓ afterload) >> - [[diabetic nephropathy]] (↓ BP at the glomerulus) >> - (⭐️) when [[ACE inhibitors]] aren't tolerated due to cough > >> [!caution] Contraindications >> - [[hyperkalemia]] >> - [[hypotension]] >> - worsening kidney function >> - [[pregnancy]] #### 💊 [[Mineralcorticoid Receptor Antagonists]] ("---one" drugs) > [!blank] > > [!multi-column] > >> [!drugs] MRA Examples > >> - [[spironolactone]] > > > >> [!blank|wide-5] > >> - ↑ excretion of Na+ > >> - ↑ excretion of H2O (i.e., a [[diuretics|diuretic]]) > [!multi-column] >> [!check|wide-3] Indications >> - [[systolic heart failure|HFrEF]] >> - [[ascites]] (i.e., in patients with [[cirrhosis]]) → combine with [[furosemide]] >> - use in addition to other medications for [[essential hypertension]] > >> [!fail] Side Effects >> - [[hyperkalemia]] >> - [[gynecomastia]] (androgen-antagonist effects) #### 💊 [[Beta-Blockers]] ("---lol" drugs) > [!blank] > > [!multi-column] > >> [!drugs] Beta-Blocker Examples > >> - [[metoprolol]] (cardioselective; blocks β1 receptors) > >> - [[atenolol]] > >> - [[propranolol]] (non-selective; blocks β1 and β2 receptors) > >> - [[carvedilol]] (3rd gen; blocks β1, β2, and α receptors) > > > >> [!blank] > >> - 📉 ↓ HR by inhibiting the [[sinoatrial node|SA node]] > >> - ⚡️ ↓ conduction velocity through the heart > >> - 💊 considered to be Class II antiarrhythmics > [!multi-column] >> [!check] Indications >> - [[systolic heart failure|HFrEF]] >> - post-[[myocardial infarction|MI]] >> - (⭐️) rate control in [[atrial fibrillation]] >> - [[coronary artery disease]] > >> [!caution|wide-3] Contraindications >> - (⭐️) [[asthma]] - ***DO NOT USE BETA BLOCKERS IN PATIENTS WITH ASTHMA!!*** → can lead to bronchospasm #### 💊 [[Alpha Blockers]] > [!blank] > > [!multi-column] > >> [!drugs] Alpha-1 Blocker Examples > >> - [[tamsulosin]] > >> - [[doxazosin]] > >> - [[terazosin]] > >> - [[silodosin]] > > > >> [!blank] > >> - vasodilation > >> - relaxes smooth muscle > [!multi-column] >> [!check] Indications >> - [[hypertension]] >> - (⭐️) [[benign prostatic hyperplasia]] (BPH) > >> [!caution|wide-3] Contraindications >> - #### 💊 [[Calcium Channel Blockers]] Generally, do NOT use [[calcium channel blockers]] for heart failure. They tend to worsen edema and the nondihydropyridines tend to worsen cardiac function. ###### [[Dihydropyridines]] ("---pine" drugs) *Basically the opposite of nondihydropyridines - they affect vasodilation but NOT contractility + conduction.* > [!blank] > > [!multi-column] > >> [!drugs] Dihydropyridine Examples > >> - [[amlodipine]] > >> - [[nifedipine]] > > > >> [!blank|wide-5] > >> - potent vasodilators > >> - NO effect on SA node (unlike beta-blockers) or contractility > [!multi-column] >> [!check|wide-3] Indications >> - (⭐️) [[hypertension]] >> - [[coronary artery disease]] >> - 🚫 NO USE in heart failure or MI > >> [!fail] Side Effects >> - headache >> - hypotension >> - edema ###### [[Nondihydropyridines]] *Basically the opposite of dihydropyridines - they affect contractility + conduction but NOT vasodilation.* > [!blank] > > [!multi-column] > >> [!drugs] Nondihydropyridine Examples > >> - [[diltiazem]] > >> - [[verapamil]] > > > >> [!blank|wide-5] > >> - ↓ contractility > >> - ↓ cardiac conduction > >> - NO effect on vasodilation > [!multi-column] >> [!check|wide-3] Indications >> - (⭐️) rate control in [[atrial fibrillation]] >> - 🚫 NO USE in heart failure (can worsen cardiac output) > >> [!fail] Side Effects >> - bradycardia >> - worsening cardiac output >> - edema #### 💊 [[Digoxin]] > [!multi-column] >> [!blank] >> Inhibits Na+/K+ ATPase, which: >> - ↑ heart contractility (by ↑ intracellular Ca2+) > >> [!blank|wide-2] >> Indirectly affects the [[10 - cranial nerve X|vagus nerve]], which: >> - ↑ parasympathetic tone >> - ↓ HR (by ↓ [[sinoatrial node|SA node]] firing rate & ↓ conduction through the [[atrioventricular node|AV node]]) > [!multi-column] >> [!check] Indications >> - (⭐️) [[systolic heart failure|HFrEF]] > >> [!fail] Side Effects >> - narrow therapuetic window >> - long ½ life >> - drug interactions can ↑ levels #### 💊 [[Nitroglycerin]] ↑ [[nitric oxide]], which: > [!multi-column] >> [!blank] >> - leads to vasodilation >> - ↓ myocardial oxygen demand >> - ↓ coronary spasms > >> [!check] Indications >> - [[coronary artery disease|myocardial ischemia]] >> - (⭐️) [[myocardial infarction]] #### 💊 [[Anticholinergics]] These drugs block [[acetylcholine]] at muscarinic receptors: - ↓ parasymathetic tone - ↑ heart rate [[atropine]] is a classic anticholinergic agent. - Hot as a Hare (i.e., fever) - Dry as a Bone (i.e., anhidrosis, dry mouth) - Red as a Beet (i.e., red flush to the skin) - Blind as a Bat (i.e., dilated pupils) - Mad as a Hatter (i.e., psychosis, delirium) ###### Cardiac Drugs Summary Table | Drug Class | Drug Names | Examples | Indications | Contraindications | Heart Rate | Preload | Afterload | Contractility | | --------------------------------------- | ---------- | ------------------------------------------- | ---------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------- | ------- | --------- | ------------- | | [[ACE inhibitors]] | _--pril_ | [[ramipril]] | [[heart failure]], [[hypertension]] | [[pregnancy]], [[renal artery stenosis]], [[hyperkalemia]] | = | ↓ | ↓ | = | | [[angiotensin receptor blockers\|ARBs]] | _--sartan_ | [[valsartan]] | [[heart failure]], [[hypertension]] | [[hyperkalemia]] | = | ↓ | ↓ | = | | [[alpha blockers]] | _--osin_ | [[doxazosin]] | | | = | = | ↓ | ↓ | | [[beta-blockers]] | _--lol_ | [[metoprolol]], [[labetalol]], [[atenolol]] | [[angina]], post-[[myocardial infarction\|MI]], [[tachycardia]], [[heart failure]] | - [asthma](https://publish.obsidian.md/maggies-med-notes/00+-+Conditions/Respiratory/obstructive+lung+disease/asthma) - [COPD](https://publish.obsidian.md/maggies-med-notes/00+-+Conditions/Respiratory/obstructive+lung+disease/chronic+obstructive+pulmonary+disease/chronic+obstructive+pulmonary+disease) - [heart blocks](https://publish.obsidian.md/maggies-med-notes/00+-+Conditions/Cardiovascular/arrhythmias/heart+blocks/heart+blocks) | ↓ | = or ↓ | ↑ | ↓ | | [[calcium channel blockers]] | _--dipine_ | [[amlodipine]] | [[angina]], [[diabetes]], [[stroke]], [[hypertension]], [[atrial fibrillation]] | [[heart blocks]], [[heart failure]] | = | ↓ or = | ↓ | ↓ | | [[diuretics]] | _--ide_ | [[furosemide]], [[hydrochlorothiazide]] | [[heart failure]], [[hypertension]] | [[gout]] | = | ↓ | ↓ | = | # HYPERTENSION #### (⭐️) Triple Therapy for Hypertension - ① [[ACE inhibitors]] (or an [[angiotensin receptor blockers|ARBs]] if they are intolerant to the ACEi) - ② [[diuretics]] (e.g., [[furosemide]]) - ③ [[calcium channel blockers]] (usually a [[dihydropyridines|dihydropyridine]] like [[amlodipine]]) *NOTE: sometimes, a 4th drug - [[spironolactone]] - is added.* > [!condition] Conn Syndrome > [[primary aldosteronism|Conn syndrome]] (aka primary hyperaldosteronism) is present in 5-10% of patients with hypertension. They will often have severe, treatment-resistant hypertension (≥ 3 drugs). > - 🔍 consider [[aldosterone and plasma renin activity|aldosterone renin ratio]] + aldosterone suppression tests to diagnose - *see [[01 - Clinical Presentation and Evaluation of Adrenal Gland Disease#Investigations|here]] for more details.* # HEART FAILURE There are many different types of [[heart failure]]. Most often, it is a problem of ↓ cardiac output (different types reviewed below), but it can also arise due to ↑ cardiac output requirements such as in [[pregnancy]]. > [!caution] Caution > NOTE: [[calcium channel blockers]] should NOT be used in heart failure, because they worsen cardiac output. ![[heart failure classification.png]] #### Left-Sided Heart Failure Symptoms arise because the [[left ventricle]] cannot pump blood through the body effectively, so blood/fluid backs up into the lungs. > [!multi-column] >> [!ECG] Systolic Heart Failure ([[systolic heart failure|HFrEF]]) >> - ejection fraction < 40% >> - ↑ afterload ("pressure" problem) >> - [[dilated cardiomyopathy|ventricular dilation]] > >> [!ECG] Diastolic Heart Failure ([[diastolic heart failure|HFpEF]]) >> - ejection fraction > 50% >> - ↓ preload ("volume" problem) >> - [[ventricular hypertrophy]] #### (⭐️) Triple Therapy for [[systolic heart failure|HFrEF]] | | Drug Type | Reason | Example | | --- | -------------------------------------------------------------------------------------- | ----------------------------- | ------------------- | | ① | [[ACE inhibitors]] (can use [[angiotensin receptor blockers\|ARBs]] if intolerant) | ↓ BP, vasodilation, ↓ fluid | [[ramipril]] | | ② | [[beta-blockers]] | ↓ HR, ↓ heart's oxygen demand | [[metoprolol]] | | ③ | [[mineralcorticoid receptor antagonists\|MRAs]] | ↓ fluid (thus ↓ afterload) | [[spironolactone]] | #### Perfusion Status ![[volume and perfusion status in HF.png]] #### (⭐️) AHA and NYHA Classification Systems > [!multi-column] >> [!blank] >> ###### American Heart Association >> *The AHA proposed the following staging of heart failure in which **progression occurs in only one direction** using risk factors:* >> >> | Stage | Description | >> | ---- | ---- | >> | A | **High risk for developing HF**. No structural disorder of the heart. | >> | B | Structural disorder of the heart is present, but **no symptoms of HF** have developed. | >> | C | **Past or current symptoms of HF** that are associated with underlying heart disease. | >> | D | **End-stage disease**; requires specialized treatment strategies | > >>[!blank] >> ###### New York Heart Association >> *The New York Heart Association proposed the following method of classifying the extent of heart failure:* >> >> | Class | Description | >> | ---- | ---- | >> | I | Cardiac disease, but **no symptoms** and **no limitation** in ordinary physical activity. | >> | II | **Mild symptoms** and **slight limitation** during ordinary activity. | >> | III | **Significant limitation** in activity due to symptoms. Comfortable only at rest. | >> | IV | **Severe limitations**. Symptoms are present **even while at rest**. | # PERICARDITIS >[!ECG|wide-3] [[Pericarditis]] > - ❤️‍🩹 inflammation of the [[pericardium]] > - 🦠 viral infections are the most common cause (can also be bacterial, but less common) > - 🤕 non-infectious causes include post-[[myocardial infarction|MI]] (i.e., [[Dressler syndrome]]), cancer, chest trauma, and autoimmune > - 🫁 #pain/pleuritic-chest-pain (SHARP and sudden) - worse when lying down and breathing in (better when sitting up or leaning forward) > - 📈 widespread (most/all leads) [[ST elevation]] on EKG and > - 💊 treated with [[NSAIDs]] (1-2 weeks) and [[steroids]] if needed > - 🏃‍♂️ restrict exercise for 3 months (prevents friction of the pericardial layers) # ENDOCARDITIS > [!multi-column] >> [!ECG|wide-2] [[Endocarditis]] >> - ❤️‍🩹 infection of the heart valves >> - 3️⃣ most commonly affects the [[tricuspid valve]] >> - 🦠 commonly caused by [[Staphylococcus aureus]] >> - 👀 risk factors include younger age, male, IV drug use, [[congenital heart disease]], [[valvular heart disease]] >> - ⛏️ **non-bacterial thrombotic endocarditis** (NBTE) creates a rough surface for the attachment of platelets and bacteria >> - 💊 treated with [[vancomycin]] x 6-12 weeks > >> [!blank] >> ![[endocarditis Duke Criteria.png]] # CONGENITAL HEART DISEASE > [!multi-column] >> [!pink] ACYANOTIC >> - isolated valve lesions (e.g., [[bicuspid aortic valve]], [[mitral regurgitation]]) >> - [[coarctation of the aorta]] >> - isolated R → L shunt lesions (e.g., [[autism spectrum disorder|ASD]], [[ventricular septal defect|VSD]], [[patent ductus arteriosus]]) > >> [!blue] CYANOTIC >> *Give [[dinoprostone]] to keep [[ligamentum arteriosum|ductus arteriosus]] patent in cyanotic newborns.* >> - ![[one.png|20]] [[persistent truncus arteriosus]] >> - ![[two.png|20]] [[transposition of the great vessels]] >> - ![[three.png|20]] [[tricuspid atresia]] (↓ pulmonary blood flow) >> - ![[four.png|20]] [[tetralogy of Fallot]] (↓ pulmonary blood flow) >> - ![[five.png|20]] [[total anomalous pulmonary venous return]] # ATHEROSCLEROSIS [[Atherosclerosis]] develops when plaques develop along the vessels walls, thought to occur due to an *exaggerated repair process (inflammation)*. Patients are generally ASYMPTOMATIC until the vessel(s) are at least 70% occluded. Plaques can form anywhere in the body, leading to: - 🫀 [[angina]] due to ischemia, [[myocardial infarction]], or [[abdominal aortic aneurysm]] due to dilation of the vessel - 🧠 [[stroke]] - 🦵 [[intermittent claudication]] or [[critical limb ischemia]] - 🤰 [[intestinal ischemia|ischemic gut]] # ANEURYSMS > [!multi-column] >> [!ECG] True Aneurysm >> - dilation of the ***entire vessel wall*** >> - "fusiform" if symmetrical >> - "saccular" if asymmetrical > >> [!ECG] False Aneurysm >> - puncture in the vessel causes a ***bulging hematoma*** ![[types of aneurysms.png]] #### Abdominal Aortic Aneurysm ([[abdominal aortic aneurysm|AAA]]) > [!multi-column] >> [!ECG|wide-2] Clinical Features >> - 🚬 90% of patients with AAAs have smoked at some point in their life >> - 🥴 rupture causes sudden-onset abdominal, back, or flank pain > >> [!treatment] >> *Treatment is aimed at preventing rupture.* >> - ⚙️ stent placement >> - 🔪 open repair / grafting # DISSECTIONS > [!multi-column] >> [!blank] >> In a [[dissection]], the blood that should be flowing in the lumen of the vessel gets into the wall of the vessel (i.e., a false lumen), where it accumulates. >> >>Most often occur in the *absence* of aneurysms. > >> [!blank] >> ![[garden hose analogy of vessel dissection.png]] #### Aortic Dissection ([[aortic dissection|AD]]) > [!multi-column] >> [!ECG|wide-2] Clinical Features >> - 😩 sudden-onset #pain/chest-pain that radiates to the upper back, often described as "**tearing**" or "**like being split in two**" >> - 🩸 BP differential in R and L arm >> - 💀 high mortality rate > >> [!treatment] >> - 📉 ↓ BP to minimize propagation (e.g., IV [[labetalol]]) >> - 🔪 graft repair (especially type A) > > [!multi-column] >> [!blank] >> ![[aortic dissection classification systems.png]] > >> [!blank] >> ###### Stanford Classification: >> - **Type A** = surgical treatment >> - **Type B** = try pharmacological treatment >> ###### DeBakey Classification: >> - based on location of origin and extent of tear # CORONARY ARTERY DISEASE [[coronary artery disease|CAD]] is characterized by ↓ blood flow to the heart due to blockage of [[coronary arteries]]. > [!multi-column] >> [!ECG] Clinical Features >> - 🚬 smoking, [[hypertension]], and poor diet/exercise are risk factors >> - 😩 angina (pressure, squeezing, burning, or tightness) >> - 🏃‍♂️ chest pain is worse with exertion >> - ✅ normal EKG and normal [[troponin test]] > >> [!treatment] >> - 💊 [[beta-blockers]] (↓ HR) >> - 💊 [[calcium channel blockers]] (↓ HR) >> - 💊 [[statins]] (↓ cholesterol) >> - 💊 [[nitroglycerin]] >> - 🔪 percutaneous [[angioplasty|angioplasty and stent]] >> - 🔪 [[coronary artery bypass|CABG]] surgery # MYOCARDIAL INFARCTION Blockage of a [[coronary arteries|coronary artery]] that leads to irreversible damage and scarring of cardiac tissue. - most often caused by an **acute thrombus (blood clot) blocking an artery that is already narrowed by a chronic plaque** > [!multi-column] >> [!ECG|wide-2] [[type I myocardial infarction|Type I MI]] >> - thrombus gets stuck in a narrowed (plaque) vessel >> - [[STEMI]] = ↑ ST segment on ECG; **full vessel occlusion** >> - [[NSTEMI]] = ↓ ST segment on ECG; **partial vessel occlusion** > >> [!ECG] [[type II myocardial infarction|Type II MI]] >> - supply-demand imbalance >> - e.g., coronary artery dissection, trauma, shock #### Cardiac Markers > [!multi-column] >> [!blank|wide-2] >> - [[troponin test]] = ↑ within 6-12 hours of a heart attack >> - might remain high for 1-2 weeks post-MI > >> [!caution] >>**DO NOT WAIT for bloodwork to come back in order to diagnose a [[STEMI]]!!!** #### ECG [[ECG]] can aid in the **localization** of the infarct (i.e., which leads are affected): - anterior leads (V4 and V3) = [[anterior interventricular artery|left anterior descending artery]] (LAD) = [[anterior STEMI]] - septal leads (V1 and V2) = septal wall of the ventricle - lateral leads (I, aVL, V5, and V6) = [[left circumflex coronary artery|left circumflex artery]] = [[lateral STEMI]] - inferior leads (II, III, and aVF) = [[right coronary artery]] = [[inferior STEMI]] > [!multi-column] >> [!ECG] #Cardio/ECG/tombstoning >> This occurs when there is 4-6mm of [[ST elevation]] at the J-point, along with T wave elevation. The resulting EKG looks like it has a "tombstone" appearance, or "concave downward". >> ![[EKG tombstoning.png]] > >> [!ECG] #Cardio/ECG/concave-upward >> This is the "typical" ST elevation appearance. >> ![[concave-upward-ST-elevation.jpg]] > >> [!ECG] #Cardio/ECG/isolated-J-point-elevation >> Sometimes, the J-point does not have very eye-catching ST-elevation. This is a pattern that is less common during an acute MI (it is more common in [[benign early repolarization]]). Compare to an old ECG if possible. >> ![[J-point elevation.png]] ###### Anterior STEMI An [[anterior STEMI]] = blockage of the [[anterior interventricular artery|LAD]]. - [[ST elevation]] in V3 and V4 ![[anterior STEMI EKG.png]] ###### Inferior STEMI An [[inferior STEMI]] = blockage of [[right coronary artery]]. - [[ST elevation]] in Lead I, Lead II, and aVF ![[inferior STEMI EKG.png]] ###### Posterior STEMI A [[posterior STEMI]] = blockage of the [[left circumflex coronary artery|left circumflex artery]]. - [[ST depression]] in V1, V2, V3, and V4 ![[posterior STEMI EKG (12-lead).png]] #### Treatment of MI ###### Supportive Medications > [!multi-column] >> [!blank] >> *Regardless of reperfusion strategy, these medications are given to slow progression of cardiac injury*. >> - 💊 [[asprin]] >> - 💊 [[nitrates]] >> - 💊 [[beta-blockers]] (as long as there's no [[shock]], [[heart failure]], [[bradycardia]], or [[heart blocks]]) > >> [!caution] >> *Treatments that are NO LONGER INDICATED:* >> - morphine >> - oxygen >> - antiarrhythmics (other than beta blockers) >> - NSAIDS (other than asprin) ###### Reperfusion Techniques The most important step in the management of MI is to re-establish coronary perfusion ASAP. > [!multi-column] >> [!treatment] [[angioplasty|PCI]] >> *Generally, [[angioplasty|PCI]] is the preferred reperfusion technique within 120 mins (preferably 90 mins) * >> - [[coronary arteries]] are accessed via the radial or femoral artery >> - balloon device is used to push open the walls of the vessel >> - sometimes, a stent is placed to hold the vessel open > >> [!treatment] Antifibrinolytics >> *If PCI is not available or too much time has passed, antifibrinolytic therapy can be used as a reperfusion technique. >50% ↓ in [[ST elevation]] is considered to be successful fibrinolysis.* >> - 💉 bolus of [[heparin]] (to make sure there is enough in the blood) >> - 💊 high-dose [[statins]] are given to stabilize the plaque >> - 🩸 [[tissue plasminogen activator|tPA]]