Robbin's 12: The Heart Flashcards
Bradyarrhythmias less than 50/min suggest a disorder of what part of the heart?
Bradyarrhythmias less than 50/min suggest an SA node disorder. SA node dysfunction may worsen with cardioactive drugs, such as cardiac glycosides, β-adrenergic blockers, calcium channel blockers, and amiodarone.
A 66-year-old man has had cough and worsening shortness of breath for 3 years. On examination, there is dullness to percussion at both lung bases and poorly audible breath sounds. On physical examination, pulse is 77/min and BP is 110/80 mm Hg. He does not have anginal pain. His liver span is increased to 14 cm. He has pitting edema to his knees. Jugular venous distention is noted to the angle of the jaw at 45-degree elevation of his head while lying down. What is most likely causing his heart disease?
Smoking These findings are consistent with right-sided congestive heart failure leading to peripheral edema, body cavity effusions (pleural effusions in this case), passive congestion of the liver, and jugular venous distension. Pure right-sided failure is less common than left-sided failure, and the former most often follows pulmonary disease (cor pulmonale). Chronic obstructive pulmonary disease (COPD) is more common than restrictive lung disease, and smoking leads to COPD.
A 62-year-old woman has had increasing dyspnea for the past 2 years. She now awakens at night with air hunger and cough productive of frothy sputum. On examination, she has rales in all lung fields. Her point of maximal impulse is strong and displaced laterally. Echocardiography shows a decreased ejection fraction of 30% with concentric increase in left ventricular wall size. The valves appear normal. What underlying diseases does she have?
HTN Left-sided congestive heart failure leads to pulmonary congestion and edema. Systemic hypertension is common and leads to pressure load with predominantly concentric left ventricular hypertrophy with systolic dysfunction.
A 41-year-old woman has been awakened at night with “air hunger” for the past year. She notes sleeping better while sitting up in bed. Her serum B-type natriuretic peptide is >400 pg/mL (very high). What cardiac disease best explains her condition?
Rheumatic valvulitis Paroxysmal nocturnal dyspnea is a feature of left-sided congestive heart failure, and rheumatic heart disease most often involves the mitral, aortic, or both valves, and left-sided valvular disease leads to pulmonary edema.
An infant born at term is noted to have cyanosis during the first week of life. On examination a heart murmur is auscultated. Abnormal findings with echocardiography include an overriding aorta, ventricular septal defect, right ventricular thickening, and pulmonic stenosis involving the fetal heart. This infant is most likely to have an inherited mutation involving which gene?
NOTCH2 There are a number of mutations in genes linked to congenital heart disease that encode proteins in transcription or signaling pathways. The NOTCH pathway plays a role in modulation of vascular development, including cardiac outflow tracts. NOTCH2 mutations are associated with tetralogy of Fallot, as in this infant.
KCNQ1 mutations may be seen with what cardiac disease?
KCNQ1 mutations may be seen with long QT syndrome
Following an uncomplicated pregnancy, a term infant appears normal at birth, but at 1 day of life the infant develops respiratory distress. On physical examination the infant has tachypnea, tachycardia, and cyanosis. There is an S1 ejection click and a split S2 with prominent P sound. A radiograph shows normal heart size but prominent hilar vascular markings. Echocardiography shows a small left atrium, large right atrium, normally sized ventricles, widely patent foramen ovale, and normally positioned aorta and pulmonary trunk. What type of congenital heart disease does this infant most likely have?
Total anomalous pulmonary venous connection This shunt results from abnormal confluence of pulmonary veins leading to the right atrium (or systemic veins), and not the left. Obstruction is often present, as in this case, with pulmonary congestion. Deoxygenated systemic and oxygenated pulmonary venous blood mix in the right atrium.
T/F: Coarctation of the aorta is associated with cyanosis.
False
Uncorrected VSD carries what complication?
Pulmonary HTN
A 3-year-old child is developing normally. Physical examination reveals a low-pitched cardiac murmur. An echocardiogram shows the presence of an ostium secundum, with a 1-cm defect. What abnormality is most likely to be found in this child?
Left to right shunt A persistent ostium secundum is the most common form of atrial septal defect. Because atrial pressures are low, the amount of shunting from the left atrium to the right atrium is small, and this lesion may remain asymptomatic for many years. Eventually, pulmonary hypertension can occur, with reversal of the shunt.
Cyanosis is a feature of what pathological cardiac shunt?
Right to left
What kind of shunt is PDA?
Although often not causing a large shunt defect, a patent ductus arteriosus can produce a significant murmur and predispose to infection. This left-to-right shunt may eventually result in pulmonary hypertension.
A 5-year-old girl who is below the 5th percentile for height and weight for age has exhibited easily fatigability since infancy. On physical examination, she appears cyanotic. Her temperature is 37° C, pulse is 82/min, respirations are 16/min, and blood pressure is 105/65 mm Hg. Pulse oximetry shows decreased oxygen saturation. One month later, she has fever and obtundation. A cerebral CT scan shows a right parietal, ring-enhancing, 3-cm lesion. What congenital heart diseases is the most likely diagnosis?
Truncus arteriosus Cyanosis at this early age suggests a right-to-left shunt. Truncus arteriosus, transposition of the great arteries, and tetralogy of Fallot are the most common causes of cyanotic congenital heart disease.
A 15-year-old boy complains of pain in his legs when he runs more than 300 m. Physical examination shows temperature, 36.8° C; pulse, 76/min; respirations, 22/min; and blood pressure, 165/90 mm Hg. The radial pulses are 4+, and the dorsalis pedis pulses are 1+. Arterial blood gas measurement shows a normal oxygen saturation level. What congenital cardiovascular anomaly is most likely to be present in this patient?
Coarctation of the aorta In children and adults, the coarctation is typically postductal, and collateral branches from the proximal aorta supply the lower extremities, leading to the large pulse differential between upper and lower extremities. Collaterals often involve intercostal arteries whose enlargement produces “rib notching” on chest radiographs. Diminished renal blood flow below the coarctation increases renin production and promotes hypertension.
Transposition of the great arteries results in:
Transposition of the great arteries results in a right-to-left shunt with cyanosis.
What is truncus arteriosus?
Truncus arteriosus is an anomalous, incomplete separation of the pulmonic and aortic trunks.
T/F: Atherosclerosis is accelerated with diabetes mellitus.
True
The cystic medial necrosis that occurs in Marfan syndrome most often involves what section of the aorta?
The cystic medial necrosis that occurs in Marfan syndrome most often involves the ascending aorta and predisposes to dissection that could involve coronary arteries, although with external compression.
Calcific aortic stenosis leads to what cardiac pathology?
Calcific aortic stenosis leads to left-sided congestive heart failure (CHF), and the extra workload of the left ventricle may cause angina pectoris.
Aschoff bodies are found in what diagnosis?
Rheumatic myocarditis is characterized by minimal myocardial necrosis with foci of granulomatous inflammation (Aschoff bodies).
Hemorrhage and contraction bands in necrotic myocardial fibers are most likely to be seen with infarction in what clinical setting?
Thrombolytic therapy Reperfusion of an ischemic myocardium by spontaneous or therapeutic thrombolysis changes the morphologic features of the affected area. Reflow of blood into vasculature injured during the period of ischemia leads to mitochondrial dysfunction, followed by leakage of blood into the tissues (hemorrhage).
