Cardiovascular HY GURU PDF

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HyGuru Learn. Integrate. Apply.

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Created by: Rahul Damania, MD, David Shafran, MD & the HyGuru community

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Cardiovascular (CV)

QID

Topic

Educational Objective

HyGuru: A Step Beyond

System

Subject

Repeats

1623

Left atrial enlargement

Left atrial dilation can cause dysphagia Cardiovascular (CV) CV dysphagia can result from external compression of the • Rarely can compress left recurrent esophagus by a dilated and laryngeal nerve posteriorly displaced LA in pts w/ Anterior surface of heart RHD and MS/MR. • Right atrium superiorly • Right ventricle inferiorly

Anatomy (Anat)

1

1805

Varicocele

Pressure in the left renal vein may Right gonadal vein > IVC Cardiovascular (CV) become ↑ due to compression •Left gondal vein > L renal vein > IVC where the vein crosses the aorta • L renal vein runs between SMA and beneath the SMA. This aorta (can be compressed) > varicocele "nutcracker effect" can cause hematuria and flank pain. Pressure can also be ↑ in the left gonadal vein, leading to formation of a varicocele.

Anatomy (Anat)

1

1884

CT abdomen

The IVC is formed by the union The Superior Mesenteric Vein joins the Cardiovascular (CV) of the right and left common iliac Splenic vein to form the Portal vein veins at the lvl of L4-L5. The renal arteries and veins lie at the lvl of L1. The IVC returns venous blood to the heart from the ↓ extremities, portal system, and abdominal and pelvic viscera.

Anatomy (Anat)

1

1943

Brachiocephalic vein obstruction

Brachiocephalic vein obstruction The BCV drains the ipsilateral jugular and SCVs. The bilateral • Due to pancoast tumor or thrombotic BCVs combine to form the SVC. occlusion due to central line BCV obstruction causes SSx • R side from subclavian and internal similar to those seen in SVC carotid syndrome, but only on one side of • Ext carotid drains to subclavian the body. • R brachiocephalic vein drains R lymphatic duct • Right face and arm will be swollen R subclavian or axillary obstruction • R arm swelling only SVC compression • Bilaeral face, neck and arm swelling

Cardiovascular (CV)

Anatomy (Anat)

1

1967

CABG

LAD block Cardiovascular (CV) The great saphenous vein is a superficial vein of the leg that • Left internal mammary artery is preferred originates on the medial side of vessel for bypass the foot, courses anterior to the • Great saphenous vein with multiple medial malleolus, and then travels bypasses • Superficial vein of leg up the medial aspect of the leg • Longest vein in body and thigh. It drains into the • Med foot > ant to med malleolus > femoral vein w/i the region of the med aspect of leg/thigh (3• 4cm femoral triangle, a few cm inferolateral to the pubic tubercle. Inferolateral to pubic tubercle) > femoral vein • Accessed surgically near femoral triangle (inguinal lig [sup], sartorius [lat], adductor longus [med]) Baker's cyst can compress popliteal art Small saphenous vein: lateral foot to popliteal vein

Anatomy (Anat)

1

2130

Blunt aortic injury Traumatic aortic rupture is most Blunt aortic trauma (sudden Cardiovascular (CV) often caused by the rapid deceleration) deceleration that occurs in MVCs. • Aortic isthmus (tethered by ligamentum The most common site of injury arteriosum) is more commonly ruptured is the aortic isthmus, which is • Can affect ascending aorta but is rare tethered by the ligamentum arteriosum and is relatively fixed and immobile compared to the adjacent descending aorta.

Anatomy (Anat)

1

7646

Implantable cardioverter defibrillator

LV leads in biventricular PMs course through the coronary sinus, which resides in the AV groove on the posterior aspect of the heart.

Cardiovascular (CV) Biventricular pacemaker 3 leads • 1 in RA, 1 in RV • 1 in LV via the Ra > coronary sinus (via atrioventricular groove on posterior heart) > lateral venous tributaries into LV

Anatomy (Anat)

1

11730

Sinoatrial node

The SA node consists of specialized PM cells located at the jxn of the RA and SVC. It is the site of earliest electrical activation in pts w/ sinus rhythm.

SA node Cardiovascular (CV) • Junction of right atrium and SVC AV node • Right atrium near septal cusp of tricupsid valve near coronary sinus

Anatomy (Anat)

1

11832

Retinal artery occlusion

RAO is a cause of acute, painless, Internal carotid > opthalmic artery > Cardiovascular (CV) retinal artery monocular vision loss. It is usually caused by TE • Retinal artery occlusion: painless vision complications of atherosclerosis loss with cherry red spot on macula traveling from the ICA and through the ophthalmic artery.

Anatomy (Anat)

1

11956

AV node

The AV node is located on the endocardial surface of the RA, near the insertion of the septal leaflet of the TV and the orifice of the coronary sinus.

AV node is located near the insertion of Cardiovascular (CV) the septal leaflet of the tricupsid valve and the orifice of the coronary sinus • Opening of the pulmonary vein is the MC location of ectopic A Fib generation • Isthmus between the IVC and tricuspid annulus is site of ablation for A Flutter SA node is located in the upper right anterior portion near the opening for the SVC

Anatomy (Anat)

1

12046

Subclavian steal syndrome

Subclavian steal syndrome occurs due to severe stenosis of the proximal SCA, which leads to reversal in blood flow from the contralateral vertebral artery to the ipsilateral vertebral artery. Pts may have SSx related to arm ischemia in the affected extremity (eg, exercise-induced fatigue, pain, paresthesias) or vertebrobasilar insufficiency (eg, dizziness, vertigo).

Cardiovascular (CV)

Anatomy (Anat)

1

654

Penetrating thoracic trauma

Cardiovascular (CV) The LV forms the apex of the Stab in 5th intercostal space at the heart and can reach as far as the midline in lateral direction will 5th ICS at the left MCL. All other penetrate the left lung • Lung extend above 1st rib chambers of the heart lie medial • Stab wound more medial and deeper to the left MCL. The lungs could hit the left ventricle (anterior surface overlap much of the anterior covered by the lung) surface of the heart. • Apex at midclavicular line Heart • Anterior surface: RV • Inferior surface: RV + LV touching central tendon • Posterior surface: LA Azygos vein • Posterior mediatinum immediately to the right of the midline

Anatomy (Anat)

2

1699

Penetrating thoracic trauma

The RV composes most of the heart's anterior surface. A deep, penetrating injury at the left sternal border in the 4th ICS would puncture the RV.

Stab wound to 4th intercostal left sternal Cardiovascular (CV) body • Skin • Pec major • Ext intercostal • Internal intercostal • Internal thoracic art and vein • Trasversus thoracis muscle • Parietl pleura • Pericardium • R ventricle Stab to the right of the vertebral body from behind could injury IVC Stab to 2nd intercostal left sternal border could injure pulmonary trunk L atrium: posteriod surface of heart L ventricle: lateral surface of heart

Anatomy (Anat)

2

2023

Central venous catheter

Cardiovascular (CV) The common cardinal veins of the Central line developing embryo drain directly • Subclavian or internal jugular vein into the sinus venosus. These • SVC comes from common cardinal veins cardinal veins ultimately give rise which drain into the sinus venosus to the SVC and other constituents Embryonic veins of the systemic venous • Umbical > ligamentum teres hepatis circulation. • Vitellin > portal system • Cardinal >sinus venosus > SVC

Anatomy (Anat)

2

8332

Echocardiography The LA forms the majority of the TEE posterior surface of the heart and • Pointed anteriorly: left atrium, atrial resides adjacent to the esophagus. septum and mitral valve Enlargement of the LA can compress the esophagus and cause dysphagia.

Cardiovascular (CV)

Anatomy (Anat)

2

8333

Cardiovascular (CV) Echocardiography The descending thoracic aorta lies TEE posterior to the esophagus and the • If pointed posteriorly: will see descending LA. This position permits clear aorta visualization of the descending RALS aorta by TEE, allowing for the • Right pulmonary artery is Anteriot to detection of abnormalities such as bronchi Left pulmonary artery is Superior to bronchi dissection or aneurysm. SVC • Formed behind right 1st costal cartilage • Compressed by pancoast tumor or mediastinal mass Central venous The femoral triangle (lateral to Femoral vein Cardiovascular (CV) catheter medial) consists of the femoral • Just medial to femoral art (1 cm below nerve, femoral artery, femoral inguinal ligament, 0.5• 1 cm medial to vein, and deep inguinal femoral art) nodes/lymphatic vessels. • NAVEL from lat to med Cannulation of the femoral vein should occur approximately 1 cm below the inguinal ligament and just medial to the femoral artery pulsation.

Anatomy (Anat)

2

Anatomy (Anat)

2

Cardiovascular (CV) Cardiac Cath • Cath into femoral or radial artery • Middle of hip below inguinal lig • Arterial puncture ABOVE the inguinal ligament increases risk for retroperitoneal hemorrhage • Cannot be controlled by manual pressure • Present with hemodynamic instaibility, hypotension Right paracolic gutter (between ascending colon and abdominal wall): fluid accumulation > think GI org an issue PAOP is measured at the distal tip Swan Ganz Catheter Cardiovascular (CV) of the pulm artery catheter after • Catheter inserted into pulmonary artery > balloon infilated > measure P (PCWP = an inflated balloon occludes blood flow through a pulm artery LA and LV end diastolic pressure) branch. It closely corresponds to Pleural manometry • Catheter placed into pleural space and LA and LV EDP. measures pleural pressure

Anatomy (Anat)

2

Anatomy (Anat)

2

11763

11764

Cardiac catheterization

11780

Pulmonary blood flow

The optimal site for obtaining vascular access in the lower extremity during cardiac catheterization is the common femoral artery below the inguinal ligament. Cannulation above the inguinal ligament can significantly ↑ the risk of retroperitoneal hemorrhage.

15197

Cardiac catheterization

To access the left side of the heart, CVCs must cross the interatrial septum at the site of the foramen ovale. Entry into the LA allows for direct measurement of LA pressure and for access to arrhythmogenic foci on the LA myocardium or pulm veins.

Cardiovascular (CV)

Anatomy (Anat)

2

8294

Tricuspid regurgitation

IE in IVDUs commonly affects the TV, often leading to septic pulm emboli. Pts can have an early- or holo-systolic murmur of TR, which is best auscultated in the 4th or 5th ICS at the left lower sternal border.

Cardiovascular (CV)

Anatomy (Anat)

3

1751

Patent ductus arteriosus

The ductus arteriosus is derived Aortic Arch Derivatives 1: maxillary art Cardiovascular (CV) from the sixth embryonic aortic • stapedius art, hyoid art arch. A patent ductus arteriosus • common carotid, prox part of internal (PDA) causes left-to-right carotid shunting of blood that can be • left > aortic arch; right > prox part of R heard as a continuous murmur subclavian art 6: left > ductus arteriosus; right > prox pulmonary art over the left infraclavicular region. Indomethacin (a PGE2 synthesis inhibitor) can be used to close a PDA in premature infants, but surgical ligation is often necessary in older patients.

Anatomy (Anat)

4

11831

Coronary artery disease

The inferior epigastric artery is 1 External iliac art Cardiovascular (CV) of 2 branches of the external iliac • Gives off Inf Epigastric art (runs sup and artery and takes off immediately med into abdomen) proximal to the inguinal ligament. • Gives off Deep Circumflex Iliac artery It provides blood supply to the (also supplies lower abdominal wall) lower anterior abdominal wall as • Becomes common femoral artery once it it runs superiorly and medially up passes the inguinal ligament the abdomen. Medial circumflex femoral artery • Branch of Deep Femoral • Supplies femoral neck/head

Anatomy (Anat)

4

11842

Atrial fibrillation

AF is a/w ↑ risk of systemic TE. The LA appendage is the most common site of thrombus formation.

Cardiovascular (CV) A fib • Risk of systemic thromboembolism due to stasis • Left atrial appendage is MC site for clot Crista terminalis: separates smooth sinus venosus and pectinate muscles LV mural thrombus: systolic dysfunction > impaired apical wall movement

Anatomy (Anat)

5

12151

Aortic dissection

The intimal tear in Stanford type A AD (involving the ascending aorta) usually originates in the sinotubular jxn whereas the intimal flap in Stanford type B AD usually starts near the origin of the left SCA. Dissections can propagate distally to the thoracoabdominal aorta.

Cardiovascular (CV)

Anatomy (Anat)

6

1871

Coronary blood flow

The inferior wall of the LV forms RCA most of the inferior • Posterior descending art in 90% of pop (diaphragmatic) surface of the • PDA controls AV node heart and is supplied by the PDA. • Occlusion > inferior wall infarct In 85%-90% of individuals, the LAD PDA derives from the RCA (right • Give off diagonal branch dominant coronary circulation). • Supplies anterior papillary muscle Left circ • Lateral wall of LV Right marginal • From RCA • Supplies RV

Cardiovascular (CV)

Anatomy (Anat)

9

11837

Coronary blood flow

Coronary dominance is Coronary Dominance determined by the coronary artery • Determined by which artery supplies PDA supplying the PDA. The PDA • RCA 70% of time originates from the RCA in • Left circ 10% of time approximately 70%-80% of pts • Codominant 20% of time (right dominant), both the RCA LAD: supply anterior 2/3 of septum and and LCX in 10%-20% (codominant), and the LCX in 5%- ant wall of LV Left diagonal: branch of LAD and supplies lat wall of LV 10% (left dominant). The dominant coronary artery supplies Right marginal: branch of RCA and blood to the AV node via the AV supplies free wall of RV nodal artery.

Cardiovascular (CV)

Anatomy (Anat)

9

1538

Pulmonary embolism

The IVC courses through the IVC filter: prevents the propagation of Cardiovascular (CV) abdomen and inferior thorax in a DVT from the legs to the lungs • Used in pt with contraindication to location anterior to the right half of the vertebral bodies. The renal anticoagulation Renal veins join IVC at L1/L2 veins join the IVC at the lvl of L1/L2, and the common iliac Common iliac veins becomes IVC at L4 veins merge to become the IVC at the lvl of L5. IVC filters are placed in pts w/ DVT who have c/i to anticoagulation Thx.

Anatomy (Anat)

13

10467

Myocardial infarction

Leads I and aVL correspond to STEMI 1 and avL the lateral limb leads on ECG. • Lateral infarct > L circumflex Therefore, ST elevation or Q V1 V4 waves in these leads are indicative of infarction involving • Anterior infart > LAD • Distal LAD in V3 and V4 the lateral aspect of the left ventricle, which is supplied by the V1 V6+1+avL • Left main coronary artery left circumflex artery. 2,3 and avF • Inferior infarct

Cardiovascular (CV)

Anatomy (Anat)

18

12144

Myocardial infarction

Papillary muscle rupture is a lifethreatening complication that typically occurs 3-5 days after MI and presents w/ acute MR and pulm edema. The posteromedial papillary muscle is supplied solely by the PDA, making it susceptible to ischemic rupture.

Cardiovascular (CV)

Anatomy (Anat)

18

1883

Community acquired pneumonia

On posteroanterior chest x-ray, the right middle lobe is seen adjacent to the right border of the heart, which is primarily formed by the right atrium. Consolidation in the right middle lobe can obscure the X-ray silhouette of the right heart border.

• RA: most of right side cardiac silhouette Cardiovascular (CV) IVC: most inferior edge of right border • Pulmonary art: left side of silhouette just below aortic arch RV: anterior wall • SVC: flattened opacity parallel to vertebral column that terminates inferiorly at RA

Anatomy (Anat)

21

788

Homocysteine

↑ lvls of plasma homocysteine are Homocysteine to Methionine Cardiovascular (CV) an independent RFx for (Methionine synthase + methylene thrombotic events. Homocysteine tetrahydrofolate reductase + B9,12) can be metabolized to methionine Methionine to SAM • Homocysteine to cystathionine via remethylation or to cystathionine via transsulfuration. (cystathionine synthase + B6) Hyperhomocysteinemia is most Cystathionine to Cysteine (Cystathionase + B6) commonly due to genetic mutations in critical enzymes or Homocystinuria • Increased risk for athero (damages deficiencies of vitamin B12, endothelial cells) vitamin B6, and folate. B12 deficiency • Lethargy, seizures, paresthesias and hypotonia due to MMA

Biochemistry (Bioc)

2

1047

Dilated cardiomyopathy

2034

Southern blotting

1229

Thiamine deficiency causes beriberi and Wernicke-Korsakoff syndrome. Dry beriberi is characterized by symmetrical peripheral neuropathy; wet beriberi includes the addition of high-output congestive heart failure.

Cardiovascular (CV) Thiamine def • Beriberi: peripheral neuropathy and dilated cardiomyopathy • Can occur in less than 1 year of poor intake (help to differentiate between B12 def) • Infantile will present 2• 3months after birth Riboflavin def • Angular cheilosis, stomatitis, glossitis • Normocytic anemia Vit A def • Increased risk for measels (explains why this is a tx) Southern blotting is a technique x linked recessive Cardiovascular (CV) used to identify DNA mutations. • Father to son does not occur It involves restriction Southern blot for DNA endonuclease digestion of sample • DNA extracted DNA, gel electrophoresis, and • Restriction endonuclease gene identification w/ a labeled • Gel electrophoresis • DNA probe to identify target DNA DNA probe.

Biochemistry (Bioc)

8

Biochemistry (Bioc)

1

Sensitivity and specificity

When undergoing Dx testing, pts • True positive = (sensitivity) x (# of pt w/ the disease can test (+) (true actually with dz) False negative = (1• (+), TP) or (-) (false (-), FN). The sensitivity) x (# of pt actually with dz) sensitivity of a test determi...