UWorld 4/1

how to reverse a warfarin or heparin

warfarin- FFP Heparin- Protamine Sulfate

Why does red man syndrome occur with Vancomycin

Although vancomycin is generally well tolerated, a minority of patients develop "red man" syndrome (RMS), a non-allergic drug reaction that occurs when vancomycin is infused too rapidly. RMS arises due to the direct activation of mast cells by vancomycin, which results in the release of vasoactive mediators (eg, histamine). Manifestations typically arise within seconds/minutes of vancomycin infusion and include flushing, erythema, and pruritis, primarily in the neck and upper torso. Most cases resolve spontaneously with the cessation of vancomycin and the administration of diphenhydramine. Because RMS is not a true allergic reaction (not Ig-E mediated), vancomycin can be safely resumed at a slower rate once the symptoms have resolved

_____ gene mutations cause idiopathic pulmonary hypertension; symptoms include progressive dyspnea and fatigue. However, cough, wheezing, and the resolution of symptoms while traveling is unexpected. In addition, imaging often reveals enlarged pulmonary arteries

BMPR2

52-year-old man comes to the office due to a chronic cough for the last 3 weeks. The patient says, "I haven't been coughing up phlegm, but sometimes I notice some blood on the tissue when I cough particularly hard." He has smoked 2 packs of cigarettes daily for the past 30 years and drinks 3 or 4 cans of beer on weekends. He works as a welder on an assembly line and says his father died of lung cancer at age 70. Physical examination shows right-sided face and arm swelling and engorgement of subcutaneous veins on the same side of the neck. Which of the following veins is most likely obstructed in this patient? A. Axillary (%) B. Brachiocephalic (%) C. External jugular (%) D. Internal jugular (%) E. Subclavian (%) F. Superior vena cava (%)

B. Brachiocephalic (%) This patient has symptoms consistent with an obstructed right brachiocephalic (innominate) vein. This may be the result of external compression by an apical lung tumor or thrombotic occlusion as can occur when a central catheter has been in place for an extended period. The right brachiocephalic vein is formed by the union of the right subclavian vein and the right internal jugular vein. The right external jugular vein drains into the right subclavian vein, so obstruction of the right brachiocephalic vein will also cause venous congestion of structures drained by the external jugular vein. It is important to note that the right brachiocephalic vein also drains the right lymphatic duct, which drains lymph from the right upper extremity, the right face and neck, the right hemithorax, and the right upper quadrant of the abdomen.

A 44-year-old man comes to the office due to increasing shortness of breath. While climbing the stairs to his second-floor apartment, the patient must now stop halfway to catch his breath. He has a history of nonischemic cardiomyopathy and chronic heart failure with reduced ejection fraction. After evaluation, treatment with a new medication is begun that improves his symptoms by increasing urine output and decreasing peripheral vascular resistance. The medication works by inhibiting a metalloprotease to prolong the action of endogenous polypeptides. These polypeptides are most likely secreted by which of the following cell types? A. Adrenal zona glomerulosa cells (%) B. Cardiomyocytes (%) C. Hepatic stellate cells (%) D. Myocardial Purkinje fibers (%) E. Renal juxtaglomerular cells (%) F. Vascular endothelial cells (%)

B. Cardiomyocytes (%) Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are secreted by atrial and ventricular cardiomyocytes in response to myocardial stretching induced by hypervolemia. These natriuretic peptides inhibit the renin-angiotensin-aldosterone system and stimulate peripheral vasodilation and increased urinary excretion of sodium and water. Neprilysin inhibitors (eg, sacubitril) prevent the degradation of ANP and BNP, enhancing their beneficial effects in heart failure

A 64-year-old man comes to the office due to generalized edema, fatigue, and dyspnea on exertion for 2 months. The patient has a 25-year history of poorly controlled rheumatoid arthritis. Temperature is 36.9 C (98.4 F), blood pressure is 108/70 mm Hg, and pulse is 90/min. The patient is thin and appears chronically ill but is in no acute distress. There is no lymphadenopathy. Breath sounds are decreased at the lung bases. Musculoskeletal examination shows severe deformities of the hands and feet related to rheumatoid arthritis. There is pitting edema of both legs up to the knees. Peripheral pulses are normal. Urinalysis shows 4+ protein but is otherwise normal. A renal biopsy is performed. Which of the following histologic abnormalities is most likely to be seen in this patient's glomeruli? A. Crescent formation (%) B. Deposition of amorphous material (%) C. Diffuse hypercellularity (%) D. IgA deposition (%) E. No abnormalities (%)

B. Deposition of amorphous material (%) RA-->AA--> nephrotic syndrome

A 32-year-old man dies suddenly in his sleep. He had been experiencing easy fatigability for the past 6 months and mentioned that he was feeling tired "'all the time"' and needed to take naps during the day. He did not drink alcohol or use illicit drugs. He smoked a pack of cigarettes per day for 10 years. His father died from a "heart problem" at age 40. On autopsy, the heart appears grossly enlarged. A layered mural thrombus is seen in the left ventricular apex. Coronary atherosclerosis is present, with 20% narrowing of the mid-left anterior descending artery and 25% narrowing of the left circumflex artery. Which of the following is the most likely cause of death of this patient? A. Antiphospholipid antibody syndrome (%) B. Dilated cardiomyopathy (%) C. Hypertrophic cardiomyopathy (%) D. Ischemic heart disease (%) E. Restrictive cardiomyopathy (%)

B. Dilated cardiomyopathy (%) Dilated cardiomyopathy results from primary myocardial dysfunction leading to eccentric remodeling of the left ventricle. Patients can develop left ventricular mural thrombus and are at risk for sudden cardiac death due to ventricular arrhythmia. Familial dilated cardiomyopathy is typically inherited in an autosomal dominant pattern, and most commonly results from truncating mutations of the TTN gene that codes for the sarcomere protein titin.

A researcher is interested in studying whether there is an association between neural tube defects and use of acetaminophen during the first 3 months of pregnancy. He randomly chooses a group of women who have just delivered babies with neural tube defects, and a second group of women who delivered apparently healthy babies. These 2 groups were then asked about their use of acetaminophen during the first 3 months of pregnancy. Which of the following measures of association are the investigators most likely to report? A. Median survival (%) B. Odds ratio (%) C. Prevalence ratio (%) D. Relative rate (%) E. Relative risk (%)

B. Odds ratio (%) This scenario describes a typical case-control study design. People with the disease of interest (ie, cases [women who have just delivered babies with neural tube defects]) and people without this disease (ie, controls [women who delivered apparently healthy babies]) are asked about previous exposure to the risk factor being studied (eg, acetaminophen use during the first 3 months of pregnancy). The main measure of association is the odds ratio (OR). The OR can be calculated as follows: OR = (odds of exposure in cases) / (odds of exposure in controls)

BMPR2

Bone morphogenetic protein receptor type 2 inactivating mutation leads to *familial primary pulmonary hypertension* Leads to the proliferation of vascular smooth muscle

A 24-year-old man is being evaluated for gross hematuria. Cystoscopy under general anesthesia is performed. After the scope is passed into the urinary bladder, a triangular portion of the bladder floor formed by the internal urethral orifice and 2 slit-like openings is observed. Gross blood is seen oozing from one of the slit-like openings. Which of the following is the most likely cause of this patient's hematuria? A. Bladder rupture (%) B. Colovesical fistula (%) C. Renal papillary necrosis (%) D. Urethral diverticulum (%) E. Urinary bladder cancer (%)

C. Renal papillary necrosis (%) The trigone is the triangular portion of the bladder formed by 2 slit-like ureteric orifices and the internal urethral opening. Bleeding from the ureter, as seen on this patient's cystoscopy, suggests an origin in the upper urinary tract (ie, kidney or ureter). In contrast, lower urinary tract bleeding (eg, trauma, infection) originates in the bladder or urethra, and the source is typically directly visualized upon insertion of a cystoscope through the urethra into the bladder. The etiology of upper urinary tract bleeding is often identified based on other signs and symptoms, such as flank pain suggestive of a ureteral stone. Similarly, associated hypertension or proteinuria may indicate glomerular disease, and fever and pyuria are concerning for pyelonephritis. In the absence of other findings, renal papillary necrosis (RPN) should also be considered as a cause of bleeding from the upper urinary tract. This condition is characterized by infarction of the renal medullary vessels, leading to sloughing of the renal papillae and gross hematuria. RPN is common with sickle cell nephropathy or can occur with analgesic use, obstructive uropathy, or diabetes mellitus. Bleeding is often painless and self-limited.

SVC syndrome

Cause: Superior vena cava obstruction -> increase venous pressure produces edema of the upper body, cyanosis, dilated subcutaneous collateral vessels in the chest, and headache. Cervical lymphadenopathy may also be present as a result of either stasis or metastatic involvement. More than 90% is d/t malignancy #1 - bronchogenic carcinoma -> invasion of SVC - +70% #2 - lymphoma #3 - substernal thyroid or thoracic aortic aneurysm Others: iatrogenically by indwelling catheters Management: Diuresis. Initial management of superior vena cava syndrome consists of diuresis, and for malignancies, the treatment consists of radiation and chemotherapy if applicable. Occasionally, surgical intervention or thrombolysis may be indicated for severe life-threatening complications.

A group of sports physicians plans to conduct a case-control study to investigate a possible association between adolescent idiopathic scoliosis (AIS) and sacroiliac joint (SIJ) dysfunction in young athletes. The case group will consist of young athletes who were diagnosed with AIS during a regular checkup by a sports physician. Which of the following is the most appropriate control group for this study? A. Young athletes with a diagnosis of AIS and SIJ (%) B. Young athletes with a diagnosis of AIS but not of SIJ (%) C. Young athletes with a diagnosis of AIS irrespective of SIJ status (%) D. Young athletes with no diagnosis of AIS irrespective of SIJ status (%) E. Young athletes with no diagnosis of AIS or SIJ (%) F. Young nonathletes with a diagnosis of AIS but not of SIJ (%) G. Young nonathletes with a diagnosis of AIS irrespective of SIJ status (%)

D. Young athletes with no diagnosis of AIS irrespective of SIJ status (%) In this example: The population of interest is young athletes. Therefore, both the cases and control groups must consist of young athletes (Choices F and G). The disease of interest (ie, what defines a case) is adolescent idiopathic scoliosis (AIS). Therefore, the cases must have AIS and controls must not have AIS (Choices A, B, and C). The risk factor of interest is sacroiliac joint (SIJ) dysfunction. Cases and controls must be selected irrespective of SIJ status because the presence of SIJ is what is compared between cases and controls (Choice E). Therefore, the cases are young athletes with a diagnosis of AIS irrespective of SIJ status; the controls are young athletes with no diagnosis of AIS irrespective of SIJ status because what determines whether the disease (ie, AIS) is associated with the risk factor (ie, SIJ) is the difference in the frequency of the risk factor between cases and controls.

A 53-year-old man comes to the emergency department due to progressive shortness of breath and nonproductive cough. Medical history is significant for long-standing hypertension and type 2 diabetes mellitus, for which he takes lisinopril and metformin. The patient has no drug allergies. Blood pressure is 160/100 mm Hg, pulse is 110/min, and respirations are 20/min. On physical examination, heart sounds are regular. Lung examination reveals decreased tactile fremitus over the lower right lung along with dullness to percussion. Which of the following is the most likely diagnosis? A. Bronchospasm (%) B. Emphysema (%) C. Lobar consolidation (%) D. Pericardial effusion (%) E. Pleural effusion (%) F. Pneumothorax (%) G. Pulmonary edema (%)

E. Pleural effusion (%) This patient most likely has a right-sided pleural effusion. Excess fluid within the pleural space acts to insulate vibrations and breath sounds that originate in the airways of the lungs. Consequently, tactile fremitus, the transmission of vibration from vocalized sound (eg, saying "ninety-nine"), is decreased over a pleural effusion. Breath sounds are also decreased or absent. The high density of pleural fluid compared to normal lung (alveolus-air composite) causes dullness to percussion over the effusion. (Choice A) Bronchospasm is likely to have minimal effect on tactile fremitus and dullness to percussion. (Choice B) The hyperinflated alveoli in emphysema should demonstrate hyperresonance to percussion and decreased tactile fremitus. (Choices C and G) Because sound vibrations travel faster and more efficiently through liquids than through gases, alveolar filling processes such as lobar consolidation (alveoli filled with pus) and pulmonary edema (alveoli filled with transudate) create increased breath sound intensity and increased tactile fremitus. (Choice D) A large pericardial effusion might cause dullness to percussion with decreased tactile fremitus over the precordium, but not over the lower lung. (Choice F) Like pleural effusion, pneumothorax (air in the pleural space) acts to insulate sound originating in the airways; therefore, tactile fremitus and breath sounds are decreased. However, the low density of air compared to normal lung creates hyperresonance to percussion.

A 44-year-old man is evaluated due to progressive dyspnea over the past several years. The patient has no associated chest pain or palpitations. Physical examination shows a prolonged expiratory phase without wheezes or rhonchi. CT scan of the chest demonstrates bilateral lower lobe-predominant emphysema. Further testing reveals that the patient has a protease inhibitor deficiency, which has led to increased elastin fiber breakdown. Elastin fibers within alveolar walls normally allow the lung to stretch during active inspiration and recoil during passive expiration. Which of the following most likely contributes to this property of elastin? Elastin is a fibrous connective tissue protein that provides elasticity to the skin, blood vessels, and pulmonary alveoli. The fibers can stretch to several times their length and recoil back to their original size once stretching forces are withdrawn. Elastin assembly is closely related to that of collagen.. A. Abundant interchain disulfide bridges (23%) (Choices A and B) Disulfide bridges are formed during collagen, not elastin, synthesis. B. Chain assembly to form a triple helix (14%) After post-translational hydroxylation and glycosylation of procollagen molecules, disulfide bond formation between the C-terminal propeptide regions of 3 alpha chains brings the chains into a favorable alignment for triple helix assembly. C. Heavy post-translational hydroxylation (8%) Elastin also contains proline and lysine residues; however, in contrast to those found in collagen, few of these amino acids are hydroxylated (Choice C). D. High content of polar amino acids (7%) Similar to collagen, elastin is synthesized as a large polypeptide precursor (tropoelastin) composed of about 700, mostly nonpolar, amino acids (eg, glycine, alanine, valine) (Choice D) E. Interchain cross-links involving lysine (45%) After tropoelastin is formed, it is secreted into the extracellular space where it interacts with microfibrils (fibrillin) that function as a scaffold. Next, lysyl oxidase, a copper-dependent enzyme, oxidatively deaminates some of the lysine residues of tropoelastin, facilitating the formation of desmosine cross-links between neighboring polypeptides that hold the elastin molecules together. These cross-links, along with the high content of nonpolar (hydrophobic) amino acids, account for the rubber-like properties of elastin.

E Educational objective:The rubber-like properties of elastin are due to high content of nonpolar (hydrophobic) amino acids and extensive cross-linking between elastin monomers facilitated by lysyl oxidase. Patients with alpha-1 antitrypsin deficiency can develop early-onset, lower lobe-predominant emphysema due to excessive alveolar elastin degradation.

A 46-year-old man comes to the emergency department with chest pain that began 30 minutes ago. The patient describes the pain as a tight, squeezing sensation that radiates to the left arm. He also has increased sweating and nausea. ECG shows multi-lead ST-segment elevation, and cardiac troponin levels are high. The patient has a history of alcohol and cocaine abuse, but no history of cardiac disease. He undergoes emergency cardiac catheterization and is recovering appropriately in the postanesthetic care unit. The physician is approached by a distraught woman who says she is the patient's wife and asks about his condition. She says, "I am so worried; please tell me if my husband is okay." Which of the following is the most appropriate course of action? A. Discuss the patient's medical information with the woman due to the seriousness of his condition (%) B. Discuss the patient's status with the woman only if she has appropriate identification (%) C. Explain to the woman that no information can be disclosed without the patient's permission (%) D. Explain to the woman that the patient's status cannot be disclosed as there is no way to be sure she is his spouse (%) E. Tell the woman that the patient is stable, but that further details will have to wait until the patient can give permission (%)

E. Tell the woman that the patient is stable, but that further details will have to wait until the patient can give permission (%) When the patient is incapacitated or is not present, basic information can be shared if, in the physician's professional judgment, doing so is in the patient's best interest. In this case, there is no way of knowing for sure whether informing this woman (whether she is his wife or not) is in the patient's best interest. However, the woman is distressed, and leaving her to worry for an extended period while the patient is recovering could cause the patient emotional harm if she is indeed family. The best approach to protect the patient's privacy is to explain that he is stable, but that further information (including general diagnostic and treatment information) cannot be shared until he is asked for and provides consent.

A 65-year-old woman is concerned about her risk of fracture as her mother was recently hospitalized for osteoporotic hip fracture. The patient walks her dog for a mile on most days and has no problems with balance or falling. She has a history of hypertension, hyperlipidemia, coronary artery disease, seizure disorder, and gastroesophageal reflux disease. The patient underwent menopause at age 52. She has smoked a pack of cigarettes daily for 24 years but does not drink alcohol. Weight is 56 kg (123.5 lb). Long-term use of which of the following medications may increase this patient's risk of osteoporosis and hip fracture? A. Atorvastatin (%) B. Chlorthalidone (%) C. Levetiracetam (%) D. Metoprolol (%) E. Nitroglycerin (%) F. Omeprazole (%)

F. Omeprazole (65%) Long-term acid suppression with proton pump inhibitors may be associated with an increased risk of osteoporotic fractures, possibly due to decreased calcium absorption. Other medications associated with an increased risk of osteoporosis include glucocorticoids, aromatase inhibitors, and anticonvulsants that induce cytochrome P450.

A 46-year-old previously healthy woman comes to the emergency department due to 4 days of intermittent fever, abdominal pain, and vomiting. For the past 2 days she has also had decreased urine output, skin rash, and progressive lethargy. Her temperature is 38.3 C (101 F), blood pressure is 130/80 mm Hg, and pulse is 100/min. There is a scattered petechial rash, facial puffiness, and 1+ bilateral pedal edema on physical examination. Laboratory studies show hemoglobin of 8.9 g/dL with elevated reticulocyte count and a platelet count of 26,000/mm3. Bleeding time is prolonged; prothrombin time and activated partial thromboplastin time are normal. The peripheral blood smear shows schistocytes and reduced platelets with presence of giant forms. Blood urea nitrogen is 46 mg/dL and serum creatinine is 2.3 mg/dL. Urinalysis is positive for proteinuria and hematuria. Which of the following is most likely to be seen on renal biopsy? A. Collapse and sclerosis of glomerular tufts (%) B. Crescent-shaped mass of cellular proliferation and leukocytes (%) C. Diffuse proliferation and subepithelial immunoglobulin deposits (%) D. Mesangial IgA deposition and proliferation (%) E. Patchy necrosis of tubular epithelium and loss of basement membrane (%) F. Platelet-rich thrombi in glomeruli and arterioles (%)

F. Platelet-rich thrombi in glomeruli and arterioles (%) TTP

What does the AUC have to do with screening/diagnostic tests?

The accuracy of screening or diagnostic tests (defined as the number of true positives plus true negatives divided by the number of all observations) is generally quantified by the area under the ROC curve (AUC). ROC (receiver operating characteristic) curves are created by plotting sensitivity (true-positive rate) against 1 − specificity (false-positive rate) for various cutoff thresholds (ie, the value that determines if a given test result is positive or negative). A highly accurate test is highly sensitive (high true-positive rate) and highly specific (low false-positive rate). The more accurate the test is (ie, the higher sensitivity and specificity), the closer the AUC value is to 1.0. Therefore, tests with higher AUCs are more accurate than tests with lower AUCs

Thiazide diuretics lower blood pressure by decreasing intravascular volume, reducing cardiac output, and lowering systemic vascular resistance. Thiazides inhibit Na+/Cl− co-transporters in the distal convoluted tubules, thereby decreasing reabsorption of Na+ and Cl−. The decrease in intravascular volume is partially attenuated by

The decrease in intravascular volume is partially attenuated by activation of the renin-angiotensin-aldosterone system. However, the rise in aldosterone secretion leads to increased urinary excretion of potassium and hydrogen ions, with resulting hypokalemia and metabolic alkalosis.

_____commonly contaminates natural bodies of water, municipal water supplies, and water-based cooling systems. The organism is inhaled in aerosolized water and establishes infection via the pulmonary route. Diagnosis is generally made by urine antigen testing, silver stain, or culture on buffered charcoal yeast extract agar supplemented with L-cysteine and iron.

Legionella pneumophila

Low serum potassium is a common medical condition that can result from several mechanisms, including decreased oral intake, renal or gastrointestinal loss, or increased entry into cells. This patient with a cocaine-induced myocardial infarction most likely developed acute hypokalemia due to stress-related ______ which causes potassium to shift intracellularly.

beta-adrenergic hyperactivity,

blasto mycosis

broad based budding!!

This patient with respiratory failure, hypoxemia, and thickened bronchial walls with inflammatory infiltrates and mucous gland enlargement likely had _____.

chronic bronchitis

Auscultation reveals crackles at the lung bases, an S3 gallop, and a II/VI holosystolic murmur over the apex. The patient is admitted to the hospital, and after treatment with diuretics and vasodilators his condition improves significantly. Three days later there are no appreciable gallops or murmurs on cardiac examination. Which of the following best explains the murmur heard at the time of the initial examination?

mitral regurg (in this case secondary to heart failure)

This patient with diarrhea, weight loss, and a positive tissue transglutaminase antibody assay has celiac disease, an immune-mediated hypersensitivity to dietary gluten. Celiac disease is characterized by villous atrophy in the small intestine, leading to malabsorption of

dietary fats and fat-soluble vitamins (ie, A, D, E, K). The resulting vitamin D deficiency can present as rickets in children and osteomalacia in adults. Vitamin D increases intestinal absorption of calcium and phosphorus; deficiency reduces calcium absorption, which in turn stimulates release of parathyroid hormone (PTH). Vitamin D also directly inhibits PTH release, and therefore vitamin D deficiency facilitates a significant rise in PTH (secondary hyperparathyroidism). PTH induces release of calcium and phosphorus from bones, leading to decreased bone mineralization. (Although most phosphorus in the body is in the form of hydroxyapatite in bone, circulating phosphorus is primarily in the form of phosphate/phosphoric acids.) Typical laboratory findings in vitamin D deficiency include: low 25-hydroxyvitamin D, which reflects total body vitamin D stores (PTH stimulates renal conversion of 25-hydroxyvitamin D to 1,25-dihydroxyvitamin D; therefore, 1,25-dihydroxyvitamin D may remain within laboratory norms). elevated PTH. increased alkaline phosphatase, reflecting increased bone turnover. low serum phosphorus, due to decreased intestinal absorption and increased PTH-mediated renal excretion. PTH may initially maintain normal serum calcium levels by reducing urinary calcium excretion. However, hypocalcemia may eventually develop as bone stores are depleted in later or more severe cases

which muscle inserts on the greater trochanter of the femur

gluteus medius The main actions of the gluteus medius are hip abduction and stabilization of the pelvis during ambulation. Damage to the point of insertion on the greater trochanter can result in lateral hip pain with gait instability (ie, positive Trendelenburg sign) and weakness of abduction.

This patient has β thalassemia due to a mutation in the β globin gene just before the methionine start codon (AUG) that is most likely disrupting translation initiation. Eukaryotic translation initiation requires the assembly of ribosomal subunits (60S and 40S), mRNA, initiation factors, initiator tRNA charged with methionine, and ____. The small ribosomal subunit (40S) initially binds to the 5' cap of mRNA and scans for the start codon, which is positioned near the beginning of the mRNA and is surrounded by the _____

guanosine-5'-triphosphate (GTP) Kozak consensus sequence. This short sequence identifies the specific AUG codon that serves as the initiator of translation (analogous to the Shine-Dalgarno sequence in bacteria). Mutations affecting the Kozak consensus sequence can significantly impair protein translation and have been identified in patients with α and β thalassemias

HIGH PULMONARY CAPILLARY WEDGE PRESSURE =

high left atrial pressure

This patient has a fracture of the neck of the fibula. The common peroneal nerve is the most frequently injured nerve in the leg due to its superficial location as it courses laterally around the neck of the fibula. Injury to the common peroneal nerve from a proximal fibula fracture would cause

loss of dorsal foot sensation as well as impaired dorsiflexion and eversion resulting in foot drop.

This patient with dyspnea, cough, and intermittent chest tightness likely has asthma. The correlation of symptom onset after starting a new job and relief while traveling is suggestive of

occupational asthma (OA), which accounts for up to 25% of adult-onset asthma. OA is characterized by airway inflammation, bronchial hyperreactivity, and a variable airflow obstruction triggered by a workplace exposure. Like other forms of asthma, patients may have normal chest imaging and pulmonary function tests between exacerbations.

Whereas primary MR is caused by an intrinsic defect of the mitral valve apparatus (eg, cleft in a valve cusp, myxomatous degeneration of the chordae tendineae), secondary Mitral Regurg occurs due to

other factors. Decompensated heart failure is a common cause of secondary MR because it leads to an increase in left ventricular end-diastolic volume (LVEDV), or preload, with dilation of the mitral valve annulus (the tissue on which the mitral valve cusps are mounted) and taut stretching of the chordae tendineae. The dilated annulus and restricted movement of the chordae tendineae can cause insufficient closure of an intrinsically normal mitral valve, resulting in MR. Systemic hypertension can also contribute to secondary MR by favoring relatively lower-resistance regurgitant flow.

This patient with progressive dyspnea on exertion, nonproductive cough, bilateral crackles on lung auscultation, and a right-sided pleural effusion most likely has decompensated heart failure (chronic, poorly controlled hypertension is a common cause). Pleural effusion in decompensated heart failure is primarily driven by backward transmission of pressure from the failing left ventricle to the pulmonary circulation, resulting in increased pulmonary capillary hydrostatic pressure and an increased rate of fluid inflow to the pleural space. Vascular permeability remains normal, as does vascular oncotic pressure (which is mostly determined by serum albumin concentration). Outflow through the _____ increases in response to the increased fluid inflow, but it is unable to keep up, resulting in development of pleural effusion.

parietal pleural lymphatics

Class III antiarrhythmic drugs (eg, amiodarone, sotalol, dofetilide) predominantly block

potassium channels and inhibit the outward potassium currents during phase 3 of the cardiac action potential, thereby prolonging repolarization and total action potential duration

The external jugular vein drains the _____. The internal jugular vein drains the ____

scalp and portions of the lateral face (external jugular) brain and superficial face and neck. Obstruction of the internal jugular veins would not cause arm swelling.

Common manifestations of tricuspid valve infective endocarditis include right-sided heart failure (eg, jugular venous distension, ascites, lower extremity edema) and/or______ (eg, multiple pulmonary nodules on chest x-ray). Cardiopulmonary evaluation usually reveals a blowing, holosystolic murmur heard best along the left lower sternal border that is intensified during inspiration and reduced with standing. Crackles and rhonchi are often present (in the setting of septic emboli). Echocardiography will show valvular vegetations, which frequently result in regurgitation due to incomplete valve closure.

septic pulmonary emboli

Chronic bronchitis is characterized by chronic, productive cough with airflow limitation and is part of the spectrum of chronic obstructive pulmonary disease. It is most commonly caused by _____

tobacco smoking

trigone of bladder

triangular region at the base of the urinary bladder between the openings of the two ureters and the urethra

The subclavian vein is the continuation of the axillary vein. Both drain blood from the upper extremity. Blockage at any of these 2 sites would cause

unilateral arm swelling without associated facial swelling.