Cardiology

Electrocardiogram

• sinus or not sinus? (look at P waves in II and V1)
• rate is 300 / number of large boxes between R waves, or the number of complexes on a rhythm strip x 6
• QRS narrow or wide?
• axis, look for isoelectric lead
• PR interval
• QTc interval
• Signs of MI: T wave morphology? ST elevations/depressions? Pathologic Q waves? R wave progression? LBBB?
• Signs of Heart Failure: P wave morphology? LVH?

Arrhythmias

SA node -> AV node -> bundle of His -> left/right bundles -> Purkinje fibers

• Bradyarrhythmias and Conduction Abnormalities
  • H&P: syncope, nausea, vomiting, blurred vision, dizziness
  • DDx: sinus brady, SSS, 1st degree AV block, 2nd degree AV block (Mobitz 1), 2nd degree AV block (Mobitz 2), 3rd degree AV block
  • Tx: correct electrolytes/hypothermia, atropine/dopamine, transcutaneous pacing, transvenous pacing, leadless pacing, permanent pacemaker
• Tachyarrhythmias
  • H&P: palpitations, syncope
  • DDx: Sinus tach, Multifocal Atrial Tachycardia, Afib, Aflutter, AVNRT, AVRT, WPW, Vtach, Vfib, Torsades de Pointes
  • Tx: Stable vs. Unstable. Synchronized cardioversion vs DCCV. Vagal maneuvers (blowing into a 20 ml syringe), atropine, beta blockers, amiodarone (Decrease Warfarin by 25% when starting amiodarone), digoxin, diltiazem. Rate control superior to rhythm control most of the time. Calculate a CHA2DS2-VASc for Afib patients. Consider cardioablation vs. Watchman. Always get a TEE/cardioversion for chronic Afib. The most effective AC is warfarin. Best AC is usually DOAC because of once daily oral dosing. LMWH is an alternative if they can't have a DOAC. Aflutter can be 2:1, 3:1, or 4:1 with fixed rates of 150, 100, and 75 respectively. Do NOT shock sinus tach. Treatment for WPW syndrome (ECG findings plus symptoms) is catheter ablation to avoid sudden cardiac death, due to AFib or VFib.

Congestive Heart Failure

• Systolic Dysfunction/HFrEF
  • H&P: History of CAD, hypertension, valvular disease, dilated cardiomyopathy (EtOH, Chagas, Coxsackie B), or MI. Dyspnea, PND, orthopnea, cough, hemoptysis, fatigue; S3, displaced PMI, crackles, signs of right heart failure (S4, JVD, edema)
  • Dx: LVEF < 40%, enlarged cardiomediastinal silhouette on CXR, elevated BNP
  • Tx: ACEI/ARBs, ARNIs, β blockers, SGLT2 inhibitors, Spironolactone, and LVAD all have mortality benefit; Digoxin and diuretics don't have any mortality benefit but help with symptoms and decrease hospitalizations. For acute exacerbations use LMNOP (lasix, morphine, nitrates, oxygen, positioning).
• Non-systolic Dysfunction/HFpEF
  • H&P: History of amyloidosis, sarcoidosis, hemochromatosis, or radiation leading to infiltrative or restrictive cardiomyopathy.
  • Dx: LVEF > 40%
  • Tx: SGLT2 inhibitors

Cardiomyopathy

Hypertrophic Cardiomyopathy

• H&P
• Dx:
• Tx: Aim is to preserve or increase LV volume. Beta blockers (such as metoprolol) increase filling time and decrease inotropy. If patient is intolerant (e.g. asthma exacerbations), second line is verapamil (non-dhp CCB). If medical management fails, use EtOH septal ablation.

Coronary Artery Disease

• LAD supplies the anterior 2/3 of the septum and the anterior wall of the LV.
• LCx supplies the lateral and posterolateral wall(s) of the LV.

Angina Pectoris

• H&P: History of atherosclerosis, HCL, HLD, HTN, Diabetes.
• Dx: Chest pain that is brought on by exertion, relieved by rest or nitrates. Differential includes GERD, esophageal spasm, costochondritis, pericarditis, aortic dissection, PUD, pancreatitis, shingles
• Tx: sublingual nitroglycerin, GTN

Prinzmetal Angina

• H&P: Similar to angina, but occurs mostly in young women and at rest, not with exertion, most often in the morning.

Acute Coronary Syndromes

STEMI

• H&P:
• Dx:
• Tx: Look out for complications (DARTH VADER mnemonic). PCI for patients with ST depression on exercise stress ECG test. Afib as a complication of MI or cardiac surgery usually resolves spontaneously within a few days.

Dyslipidemia

Group	Intervention
21+ w/ ASCVD or LDL > 190	High dose statin
40+ w/ LDL 70-189 w/o diabetes	Calculate 10-yr ASCVD risk: > 7.5% give high dose statin 5-7.5% give moderate dose statin < 5% no statin
40+ w/ LDL 70-189 w/ diabetes	Calculate 10-yr ASCVD risk: > 7.5% give high dose statin < 7.5% give moderate dose statin

Essential Hypertension

• H&P:
• Dx: Primary/Essential Hypertension (95% of cases). Rule out secondary causes, BP > 130/90 on three separate occasions. DDx includes secondary HTN (5% of cases; suspect if patient very young, very old, very high BP, or refractory to treatment), secondary causes listed below:
  • Endocrine: Conn syndrome (most common), Cushing's syndrome, Pheochromocytoma, Hyperthyroidism, Hyperparathyroidism
  • Renal: bilateral RAS, PKD, CKD, glomerular disease (nephrotic and nephritic syndromes)
  • Other: Cocaine, OSA, OCPs, Coarctation
• Tx: For SBP 121-130, start with 8-12 weeks lifestyle modifications and reassess. If SBP 131-139 or DBP 81-89, risk stratify based on 10-yr ASCVD risk, if > 10%, start medication, if < 10%, can do trial of lifestyle modifications. When starting medication, start with 1 or 2 agents depending on severity, reassess efficacy every month and up the dose or add another agent as needed. ACEI/ARB (good for kidney protection, don't do both), Dihydropyridine CCB (better for HTN) > non-dihydropyridine CCB (better for rate control), Beta Blockers (cardiac selective (MAN BABES) > non-selective), Thiazide-Like Diuretics > Thiazide-Type Diuretics. For most patients, the combination of ACEI/ARB + CCB is the best, so start with one of these two classes so that the second can be added later for synergy. Special population considerations: CHF (avoid CCBs, use beta blockers, ACEI/ARBs, spironolactone), CKD (use ACEI/ARB), Pregnancy (hydralazine, labetalol, nicardipine, methyldopa), post-MI (use beta blockers + ACEI/ARB), Blacks (CCB + thiazide-like diuretic), Cocaine (don't give beta blockers due to unopposed alpha).
• Hypertensive Urgency BP > 180 + mild symptoms
• Hypertensive Emergency BP > 180 + ominous symptoms

Pericardial Disease

Pericarditis

• H&P: Possible history of recent MI, improved when leaning forward, can have pleuritic chest pain, cardiac rub
• Dx: Can show calcifications on CXR
• Tx: High-dose aspirin for post-MI acute pericarditis, otherwise NSAIDs and colchicine for normal pericarditis.

Cardiac Tamponade

• H&P: Beck's triad
• Dx: Get TTE to look for pericardial effusion
• Tx: Urgent pericardiocentesis if present

Valvular Heart Disease

Cardiac Murmur Descriptions and Maneuvers

Murmur	Cardiac Phase	Description	Location	Flow Problem	Relation to Preload	Relation to Afterload
AR	Diastolic	?	Mitral	Reverse	0	+1
AS	Systolic	Loud/late peaking, soft/single S2 during inspiration	Aortic	Forward	+1	-1
MR	Systolic	?	Aortic	Reverse	0	+1
MS	Diastolic	Blowing	Mitral	Forward	0	0
MP	Systolic	Preceding Click	Aortic	Reverse	-1	-1
TR	Systolic	?	Tricuspid	Reverse	+1	0
HOCM	Systolic	?	Tricuspid	Forward	-1	-1

• Maneuvers increase afterload (hand grip, standing, valsalva), preload (passive leg raise, squatting, lying down), or both (vagal).

Endocarditis

• H&P: Janeway lesions, Osler nodes, Splinter hemorrhages
• Dx: TTE or TEE
• Tx: Long course of IV antibiotics

Bicuspid Aortic Valve

• H&P: One of the most common congenital heart defects (about 1% of the population, M>F). Systolic ejection murmur at right upper sternal border.
• Dx: TTE
• Tx: Consider balloon valvuloplasty in young adults who are symptomatic (or asymptomatic if participating in competitive sports or planning on pregnancy) who have aortic stenosis with peak gradient > 50 mmHg and no AR or aortic valve calcifications. Screen for thoracic aortic aneurysm, including in 1st degree relatives. More likely to get endocarditis.

Vascular Diseases

• Aortic Aneurism: Most are abdominal, most are below the renal arteries. Different types of repair (open vs endovascular), when to intervene (> 5.5 cm, rapidly enlarging, or causing organ damage), one time screening abdominal US recommended in ever smokers ages 65-75.
• Aortic Dissection: Stanford classification: type B (post left subclavian and descending aorta) is medically managed; type A (ascending aorta to the left subclavian or beyond) is a surgical emergency.
• Deep Venous Thrombosis: Virchow's triad, mostly occur in the legs, DVTs leading to PEs are usually in the femoral veins. Hofman's sign is neither sensitive or specific. Risk stratify based on Well's score, then get D-dimer (sensitive, not specific) if pre-test probability is low to rule out DVT. Can give therapeutic dose heparin if pre-test probability is high. Factor V Leiden increases risk of venous but not arterial thrombosis.
• Peripheral Arterial Disease: ABI
  • Carotid Artery Stenosis
• Lymphedema
  • In developed countries, is usually secondary to lymph node resection (e.g. radical mastectomy)
  • Can also be congenital or secondary to infection (developing countries)
  • Does not respond to diuretics
  • Use compression stockings or arm bands

Syncope

• Ddx includes cardiac arrhythmias (VT after MI or iso cardiomyopathy occurs without warning symptoms), vasovagal, seizures, orthostatic hypotension, SAH, vertigo, symptomatic anemia

Missed Concepts

• Verapamil inhibits renal tubular secretion of digoxin, leading to toxicity
• 6-minute walk test and cardiopulmonary exercise testing are useful tests for risk assessment prior to cardiac or pulmonary surgery.