ABTS Thoracic Surgery cheat sheet

CABG is generally preferred to PCI for left main stenosis ≥50%, multivessel CAD with diabetes, and multivessel CAD with LVEF ≤35% when anatomy is suitable.

Severe aortic stenosis: valve area ≤1.0 cm², mean gradient ≥40 mm Hg, or peak velocity ≥4.0 m/s; low-flow low-gradient AS may require dobutamine stress echocardiography.

Stanford type A aortic dissection involves the ascending aorta and requires emergency surgery; type B dissection spares the ascending aorta and is usually managed medically unless complicated by malperfusion, rupture, or refractory pain.

For cardiopulmonary bypass, activated clotting time is commonly maintained above 400-480 seconds; protamine is given at about 1 mg per 100 units of heparin to reverse anticoagulation.

Primary severe mitral regurgitation surgery triggers include symptoms, LVEF ≤60%, or LV end-systolic dimension ≥40 mm; secondary MR is managed first with guideline-directed medical therapy and cardiac team assessment.

Mechanical valves are more durable but require lifelong anticoagulation; bioprosthetic valves avoid long-term anticoagulation but have limited durability, especially in younger patients.

After CABG, aspirin is typically started within 6 hours if there is no active bleeding; dual antiplatelet therapy is considered after acute coronary syndrome or recent PCI.

Postoperative atrial fibrillation after cardiac surgery is common and is managed with rate or rhythm control; anticoagulation is considered according to stroke risk and bleeding risk.

NSCLC T staging (8th edition): T1 ≤3 cm; T2 >3-5 cm; T3 >5-7 cm or invasion of chest wall, phrenic nerve, or parietal pericardium; T4 >7 cm or invasion of mediastinum, diaphragm, or heart.

N staging: N1 ipsilateral peribronchial/hilar nodes; N2 ipsilateral mediastinal/subcarinal nodes; N3 contralateral mediastinal/hilar or any supraclavicular nodes.

Medically operable stage I-II NSCLC is treated with lobectomy and lymph node sampling; SBRT is preferred for medically inoperable stage I disease.

Sublobar resection is acceptable for peripheral NSCLC ≤2 cm with ground-glass histology or limited pulmonary reserve; otherwise lobectomy remains standard for fit patients.

Recurrent symptomatic malignant pleural effusion: indwelling pleural catheter or pleurodesis after diagnosis; thoracentesis is for initial relief and cytology.

Primary spontaneous pneumothorax: small asymptomatic cases may be observed; large or symptomatic cases need needle decompression if unstable, followed by chest tube.

Locally advanced esophageal cancer (T2-T4 or N+) is commonly treated with neoadjuvant chemoradiation followed by esophagectomy.

Thymoma is associated with myasthenia gravis; resectable thymoma is treated by complete resection, and preoperative biopsy is avoided when upfront resection is planned.

Ventricular septal defect: small restrictive defects may close spontaneously; large defects cause left-to-right shunting, heart failure, and pulmonary overcirculation, requiring repair before pulmonary vascular disease develops.

Tetralogy of Fallot: VSD, pulmonary stenosis, overriding aorta, and right ventricular hypertrophy; cyanosis severity depends on right ventricular outflow obstruction.

Transposition of the great arteries: ventriculoarterial discordance with parallel circulation; mixing via ASD, VSD, or PDA is essential, and prostaglandin E1 maintains ductal patency before arterial switch.

Coarctation repair is indicated for peak gradient ≥20 mm Hg or significant hypertension; bicuspid aortic valve and aortic arch hypoplasia are common associations.

Fontan circulation directs systemic venous return to the pulmonary arteries without a subpulmonary ventricle; late complications include arrhythmia, protein-losing enteropathy, plastic bronchitis, and liver disease.

PDA in preterm infants may be treated with indomethacin or ibuprofen; device or surgical closure is used when pharmacologic closure fails or is contraindicated.

Eisenmenger syndrome: unrepaired left-to-right shunt causes pulmonary vascular disease and cyanosis; shunt closure is contraindicated.

ASD closure is indicated for significant shunt (Qp/Qs >1.5) or right ventricular enlargement without severe pulmonary vascular disease; secundum ASD may be closed with a device.