Pestana Chap 6 - Cardiothoracic Surgery

Question 1

What do vascular rings cause? What are these symptoms?

Answer 1

1) Vascular rings produce symptoms of pressure on the tracheobronchial tree and pressure on the esophagus
2) The first include stridor and episodes of respiratory distress with “crowing” respiration, during which the baby assumes a hyperextended position
3) The latter revolve around some difficulty swallowing. (If only the respiratory symptoms are present, one should think of tracheomalacia)

Question 2

What is tracheomalacia?

Answer 2

Tracheomalacia is a process characterized by flaccidity of the supporting tracheal cartilage, widening of the posterior membranous wall, and reduced anterior-posterior airway caliber. These factors cause tracheal collapse, especially during times of increased airflow, such as coughing, crying, or feeding.

Question 3

What test usually shows extrinsic compression from the abnormal vessel in the presence of vascular rings? What test rules out tracheomalacia? What does surgery accomplish?

Answer 3

1) Barium swallow shows typical extrinsic compression from the abnormal vessel
2) Bronchoscopy shows segmental tracheal compression and rules out diffuse tracheomalacia
3) Surgery divides the smaller of the two aortic arches

Question 4

How are morphologic cardiac anomalies (congenital or acquired) best diagnosed?

Answer 4

Echocardiogram

Question 5

What do all left-to-right shunts share? What is different between them?

Answer 5

1) Share the presence of a murmur
2) Overload the pulmonary circulation
3) Long-term damage to the pulmonary vasculature
4) The volume and consequences of the shunt are different at different locations

Question 6

Describe the type of shunt an atrial septal defect produces. When is it usually recognized? What sounds are characteristic of an atrial septal defect?

Answer 6

1) Atrial septal defect has very minor, low-pressure, low-volume shunt
2) Patients typically grow into late infancy before it is recognized
3) A faint pulmonary flow systolic murmur and fixed split second heart sound are characteristic

Question 7

What is an important question to ask about a patient’s history in the diagnosis of atrial septal defect? What is the diagnostic test of choice? How is it treated?

Answer 7

1) A history of frequent colds is elicited
2) Echocardiogram is diagnostic
3) Closure can be achieved surgically or by cardiac catheterization

Question 8

In which location would a ventricular septal defect produce a heart murmur, but otherwise few symptoms? When is this type of septal defect likely to close?

Answer 8

1) Small, restrictive ventricular septal defects low in the muscular septum
2) They are likely to close spontaneously within the first 2-3 years of life

Question 9

In which location would a ventricular septal defect lead to trouble early on? What can be found on physical exam? On X-ray? What is the treatment?

Answer 9

1) Ventricular septal defects in the more typical location (high in the membranous septum)
2) Within the first few months there will be “failure to thrive,” a loud pansystolic murmur best heard at the left sternal border, and increased pulmonary vascular markings on chest x-ray
3) Do echocardiogram and surgical closure

Question 10

When does patent ductus arteriosus become symptomatic? How is it characterized? What is the diagnostic test of choice?

Answer 10

1) Patent ductus arteriosus becomes symptomatic in the first few days of life
2) There are bounding peripheral pulses and a continuous “machinery-like” heart murmur
3) Echocardiogram is diagnostic

Question 11

When should a patent ductus arteriosus be closed and how is this done? When should surgical division or radiological embolization of the patent ductus arteriosus be done?

Answer 11

1) In premature infants who have not gone into congestive heart failure, closure can be achieved with indomethacin
2) Those who do not close, those who are already in failure, or full-term babies need surgical division or radiological embolization with metal coils

Question 12

What do all right-to-left shunts share? How many are there?

Answer 12

1) They share the presence of a murmur, diminished vascular markings in the lung, and cyanosis
2) 5 are always described, all beginning with the letter T

Question 13

What is unique about truncus arteriosus?

Answer 13

It is cyanotic, but it kills by overloading the pulmonary circulation

Question 14

What is the most common cyanotic anomaly in children (5- or 6-year-old)?

Answer 14

1) Tetralogy of Fallot, which although crippling, often allows children to grow up into infancy

Question 15

How do children with Tetralogy of Fallot present?

Answer 15

1) The children are small for their age
2) They have a bluish hue in the lips and tips of their fingers
3) Clubbing
4) Spells of cyanosis relieved by squatting
5) There is a systolic ejection murmur in the left third intercostal space
6) A small heart
7) Diminished pulmonary vascular markings on chest x-ray
8) EKG signs of right ventricular hypertrophy

Question 16

How is Tetralogy of Fallot diagnosed? How is it treated?

Answer 16

1) Echocardiogram is diagnostic

2) Surgical repair is done

Question 17

What keeps children who have transposition of the great vessels alive and what must therefore be done? When should this be suspected? What test is diagnostic? How is it treated?

Answer 17

1) Transposition of the great vessels leads to severe trouble early on. The kids are kept alive by an atrial septal defect, ventricular septal defect, or patent ductus (or a combination), but die very soon if not corrected
2) Suspect this diagnosis in a 1- or 2-day-old child with cyanosis who is in deep trouble
3) Echocardiogram
4) Surgery

Question 18

What symptoms does aortic stenosis cause? What is heard on physical exam?

Answer 18

1) Aortic stenosis produces angina and exertional syncopal episodes
2) There is a harsh midsystolic heart murmur best heard at the right second intercostal space and along the left sternal border

Question 19

How should workup of aortic stenosis begin? When is surgical valve replacement indicated?

Answer 19

1) Start workup with echocardiogram
2) Surgical valvular replacement is indicated if there is a gradient of more than 50 mm Hg, or at the first indication of congestive heart failure, angina, or syncope

Question 20

Describe the pulse of a chronic aortic insufficiency, what does the murmur sound like on physical exam, and where is it located?

Answer 20

Chronic aortic insufficiency produces wide pulse pressure and a blowing, high-pitched, diastolic heart murmur best heard at the second intercostal space and along the left lower sternal border, with the patient in full expiration

Question 21

When should a patient with chronic aortic insufficiency undergo valvular replacement?

Answer 21

These patients are often followed with medical therapy for many years but should undergo valvular replacement at the first evidence on echocardiogram of beginning left ventricular dilatation

Question 22

How does acute aortic insufficiency present? How is it treated?

Answer 22

1) Acute aortic insufficiency because of endocarditis is seen in young drug addicts who suddenly develop congestive heart failure and a new, loud diastolic murmur at the right second intercostal space
2) Emergency valve replacement and long-term antibiotics are needed

Question 23

What must all patients with a prosthetic valve receive and what for?

Answer 23

Patients with a prosthetic valve need antibiotic prophylaxis for subacute bacterial endocarditis

Question 24

What is mitral stenosis caused by and when? What symptoms does it cause? How does it present on physical exam? What occurs as it progresses?

Answer 24

1) Mitral stenosis is caused by rheumatic fever many years before presentation
2) It produces dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, cough, and hemoptysis
3) There is a low-pitched, rumbling diastolic apical heart murmur
4) As it progresses, patients become thin and cachectic and develop atrial fibrillation

Question 25

How do you start workup for mitral stenosis? When is surgical repair necessary and what is done in surgery?

Answer 25

1) Workup starts with echocardiogram
2) As symptoms become more disabling, mitral valve repair becomes necessary with a surgical commissurotomy or a balloon valvuloplasty

Question 26

What is mitral regurgitation most commonly caused by? What do patients develop? What is heard on physical exam?

Answer 26

1) Mitral regurgitation is most commonly caused by valvular prolapse
2) Patients develop exertional dyspnea, orthopnea, and atrial fibrillation
3) There is an apical, high-pitched, holosystolic heart murmur that radiates to the axilla and back

Question 27

How do you start workup for mitral regurgitation? When is surgical repair necessary and what surgical procedure is preferred?

Answer 27

1) Workup starts with echocardiogram
2) As symptoms become more disabling, mitral valve repair becomes necessary with repair of the valve (annuloplasty) preferred over prosthetic replacement

Question 28

Who is the typical patient who has coronary disease?

Answer 28

Coronary disease can happen to anybody (including women), but the typical patient is a middle-aged sedentary man with a family history, a history of smoking, type 2 diabetes, and hypercholesterolemia

Question 29

What is the main reason to do cardiac catheterization in a patient with coronary disease? When is intervention indicated? What else is preferred in order to do intervention?

Answer 29

1) Progressive, unstable, disabling angina is the main reason to do cardiac catheterization and evaluate as a potential candidate for revascularization
2) Intervention is indicated if one or more vessels have 70% (or greater) stenosis and there is a good distal vessel
3) Preferably, the patient should still have good ventricular function (you cannot resuscitate dead myocardium)

Question 30

When is surgery chosen over angioplasty and vice versa for coronary disease? What is single vessel disease best treated with? What is triple vessel disease best treated with?

Answer 30

1) The general rule is the simpler the problem, the more it is amenable to angioplasty and stent; whereas more complex situations do better with surgery
2) Single vessel disease (that is not the left main or the anterior descending) is perfect for angioplasty and stent. 3) Triple vessel disease makes multiple coronary bypass (using the internal mammary for the most important vessel) the best choice

Question 31

What does post-op care of heart surgery patients often require?

Answer 31

1) Post-op care of heart surgery patients often requires that cardiac output be optimized
2) If cardiac output is considerably under normal (5 liters/min, or a cardiac index of 3), the pulmonary wedge pressure (or left atrial pressure, or left end-diastolic pressure) should be measured. Low numbers (0 to 3) suggest the need for more IV fluids. High numbers (20 or above) suggest ventricular failure

Question 32

How does chronic constrictive pericarditis present? What relieves it?

Answer 32

1) Chronic constrictive pericarditis produces dyspnea on exertion, hepatomegaly, and ascites, and shows a classic “square root sign” and equalization of pressure (right atrial, right ventricular diastolic, pulmonary artery diastolic, pulmonary capillary wedge, and left ventricular diastolic) on cardiac catheterization
2) Surgical therapy relieves it

Question 33

What does a coin lesion found on chest x-ray indicate? What is the first thing to do to workup cancer of the lung?

Answer 33

1) A coin lesion found on chest x-ray has an 80% chance of being malignant in people over the age of 50, even higher if there is a history of smoking
2) A very expensive workup for cancer of the lung, however, can be avoided if an older (a year or two) chest x-ray shows the same unchanged lesion (it is not cancer). Thus, seeking an older x-ray is always the “first thing to do” in the patient found to have a coin lesion

Question 34

What does suspected cancer of the lung require for workup?

Answer 34

1) Suspected cancer of the lung requires what is potentially an expensive and invasive workup to confirm diagnosis and assess operability
2) It all starts with a chest x-ray (which may have been ordered because of persistent cough or hemoptysis) showing a suspicious lesion (coin lesion, or infiltrate)
3) Assuming no older x-ray is available (or the lesion was not present in a previous film), two noninvasive tests should be done first: sputum cytology and CT scan (including chest and liver)

Question 35

If lung cancer diagnosis is not established by cytology, what does it require? What three factors determine how far one will proceed with the diagnostic tests?

Answer 35

1) Diagnosis of cancer of the lung, if not established by cytology, requires bronchoscopy and biopsies (for central lesions) or percutaneous biopsy (for peripheral lesions)
2) If those are unsuccessful, video-assisted thoracic surgery (VATS) and wedge resection may be needed
3) How far one goes in that sequence depends on the probability of cancer (higher in elderly with history of smoking and noncalcified lesion in CT), the assurance that surgery can be done (residual pulmonary function will suffice), and the chances that the surgery may be curative (no metastases to mediastinal or carinal nodes, the other lung, or the liver)

Question 36

What is small cell cancer of the lung treated with? What do operability and possibility of surgical cure only apply to when speaking of lung cancer?

Answer 36

1) Small cell cancer of the lung is treated with chemotherapy and radiation, and therefore assessment of operability and curative chances of surgery are not applicable
2) Operability and possibility of surgical cure applies only to non-small cell cancer

Question 37

What is operability of lung cancer predicated on? When is a pneumonectomy indicated?

Answer 37

1) Operability of lung cancer is predicated on residual function after resection, assuming pneumonectomy is required. For lobectomy, function is less of an issue
2) Central lesions require pneumonectomy. Peripheral lesions can be removed with lobectomy

Question 38

What measurement is needed for a proper operability of lung? If there are clinical findings that suggest that operability due to this measurement is the limiting factor for surgery of lung cancer, what else can be done? What is done if proper operability is not achieved?

Answer 38

1) FEV1 of 800 mL is needed
2) If clinical findings (COPD, shortness of breath) suggest this may be the limiting factor, pulmonary function studies are done. Determine FEV1, determine fraction that comes from each lung (by ventilation-perfusion scan), and figure out what would remain after pneumonectomy
3) If less than 800 mL, do not continue expensive tests. The patient is not a surgical candidate. Treat with chemotherapy and radiation

Question 39

What does potential cure by surgical removal of lung cancer depend on? What is an example of this involving chest lymph nodes?

Answer 39

1) The extent of metastases
2) Hilar metastases can be removed with the pneumonectomy, but nodal metastases at the carina or mediastinum preclude curative resection

Question 40

What scan may identify nodal metastases along with lung, adrenal, or liver metastases? What about the presence of an actively growing tumor in enlarged nodes? What is a more invasive option to sample mediastinal nodes?

Answer 40

1) CT scan may identify nodal, lung, adrenal, or liver metastases
2) PET scanning has helped define the presence of an actively growing tumor in enlarged nodes
3) Endobronchial ultrasound