RCIS cheat sheet

Informed consent requires capacity, disclosure of risks/benefits/alternatives, and voluntary agreement; documented before sedation.

Radial access first-line: perform Allen test or barbeau; sheath removal after radial typically uses patent hemostasis with compression device.

Femoral sheath removal: ACT <150-180 s, SBP <160 mmHg, hold manual pressure 15-20 min; bed rest 2-6 h per protocol.

Contrast reaction: stop injection, assess airway/breathing/circulation, give oxygen; anaphylactoid treated with epinephrine IM 0.3-0.5 mg (1:1000) in adults.

CIN prevention: isotonic saline hydration; minimize contrast volume; use lowest volume consistent with diagnostic need.

Pre-procedure labs commonly include CBC, creatinine/eGFR, coagulation studies, and type and screen for PCI.

Post-PCI access site assessment: pulses, bruit, hematoma, retroperitoneal bleed signs (flank pain, hypotension, dropping Hgb).

Vasovagal response: bradycardia with hypotension; treat with supine position, leg elevation, IV fluids, atropine if symptomatic.

Cardiac output (Fick): CO = VO2 / (CaO2 − CvO2); thermodilution CO uses area under temperature curve.

Cardiac index = CO / BSA; normal 2.5-4.0 L/min/m2.

MAP = (SBP + 2×DBP)/3; or MAP = DBP + 1/3 pulse pressure.

Systemic vascular resistance: SVR = (MAP − CVP) × 80 / CO; normal 800-1200 dyn·s·cm⁻⁵.

Pulmonary vascular resistance: PVR = (mPAP − PCWP) × 80 / CO; normal <3 Wood units (≈<240 dyn·s·cm⁻⁵).

Transpulmonary gradient = mPAP − PCWP; >12 mmHg suggests pulmonary vascular disease.

Cardiac tamponade: equalization of diastolic pressures, blunted y descent, pulsus paradoxus, elevated RA pressure.

Constrictive pericarditis: prominent y descent, pericardial knock, ventricular interdependence; differs from tamponade by y descent.

Coronary flow occurs predominantly in diastole; tachycardia shortens diastole and worsens ischemia.

Left main bifurcates into LAD and circumflex; LAD supplies anterior wall and septum; circumflex supplies lateral wall.

RCA supplies right ventricle and, in 85% of people, the posterior descending artery (right-dominant circulation).

SA node is supplied by RCA in ~60% and circumflex in ~40%; AV node usually RCA.

Aortic valve area by Gorlin: AVA = CO / (44.3 × √mean gradient).

Mitral stenosis severity: MVA >1.5 cm² mild, 1.0-1.5 moderate, <1.0 severe.

Aortic stenosis severity: AVA <1.0 cm² or mean gradient ≥40 mmHg indicates severe.

Frank-Starling: increased preload increases stroke volume up to a plateau, then worsens with overdistension.

Cine frame rate commonly 15 frames/s; higher rates improve temporal resolution at cost of dose.

LAO cranial view: good for LAD mid/distal and diagonal branches; LAO caudal shows circumflex and left main bifurcation.

RAO cranial: shows LAD and septal perforators; RAO caudal: shows circumflex and RCA.

Cranial angulation 'lays out' the LAD; caudal angulation opens the circumflex and left main.

Contrast density: use iso-osmolar or low-osmolar nonionic for cardiac angiography; dilute for small vessels.

Quantitative coronary angiography: reference diameter and percent diameter stenosis from edge detection.

Radiation dose reduction: pulsed fluoroscopy, last-image hold, collimation, increased table height, minimize magnification.

IVUS/OCT: IVUS uses 40 MHz; OCT uses near-infrared light with higher resolution (~10 µm) but requires blood clearance.

Fluoroscopy dose is proportional to time; ALARA principles: time, distance, shielding.

Inverse square law: doubling distance from source reduces dose to one quarter.

Lead apron 0.5 mm Pb attenuates ~90-95% of scatter at typical energies; thyroid shield and leaded glasses add protection.

Radiation exposure is measured in mGy (air kerma) and dose-area product (DAP) in Gy·cm².

Catheter French size: 1 Fr = 0.33 mm; 6 Fr ≈ 2 mm outer diameter.

Defibrillator synchronization: sync mode for cardioversion; unsynchronized for VF/pulseless VT.

Pacemaker/ICD magnet application: asynchronous mode; remove magnet after procedure to restore sensing.

Contrast injector pressure limits and volume settings must be verified before connection; air embolism prevention by flushing.