Mixed Deck — All CCI Topics Flashcards

Turbulent flow in a blood vessel is most likely to occur when the Reynolds number exceeds:

Answer: 2000

Reynolds numbers above approximately 2000 are associated with the transition from laminar to turbulent flow.

A sonographer asks a patient to perform the Valsalva maneuver during a venous insufficiency study while interrogating the saphenofemoral junction. What is the primary purpose of this technique?

Answer: To increase intra-abdominal pressure and test for valvular competence

The Valsalva maneuver (straining against a closed glottis) significantly increases intra-thoracic and intra-abdominal pressure. This pressure is transmitted down the venous system. In a patient with competent valves, this will cause flow to slow or cease. If the valves are incompetent, the increased proximal pressure will cause blood to flow backward (reflux) past the faulty valve, which can be detected by Doppler.

An aneurysm has the potential to be caused by all but which of the following uncommon arterial wall infections?

Answer: Measles

Explanation: Arterial wall infections such as Staphylococcus, Tuberculosis, and Syphilis can contribute to the development of aneurysms by weakening the arterial wall. However, Measles is not typically associated with arterial wall infections that lead to aneurysms.

A spectral Doppler waveform showing systolic flow above and diastolic flow below the baseline in an arterial study most likely indicates:

Answer: Bidirectional flow with forward systole and reverse diastole (triphasic pattern)

A triphasic arterial waveform shows rapid systolic forward flow, brief early diastolic flow reversal, and then slow antegrade late diastolic flow, characteristic of normal peripheral arteries.

During isovolumetric contraction, which valves are CLOSED?

Answer: All four valves are closed

During isovolumetric contraction, ventricular pressure rises but no blood is ejected; all four valves remain closed until ventricular pressure exceeds great vessel pressure.

During ventriculography, which projection best demonstrates the posterobasal wall of the left ventricle?

Answer: 45° LAO projection

The 45–60° LAO projection separates the LV into septal and lateral walls and is the best view to assess the posterobasal (inferior) wall of the left ventricle.

Which of the following would contrast echocardiography including the detection of?

Answer: All of the above

Explanation: Contrast echocardiography involves the use of contrast agents to enhance the visibility of cardiac structures during echocardiography. It can aid in the detection of various conditions, including left ventricular opacification (option A), providing a refined definition of left ventricular (LV) structural abnormalities (option B), and identifying intracardiac shunts (option C). Therefore, option D, all of the above, is the correct choice.

An ECG shows regular P waves at 75 bpm, but only every other P wave conducts. The PR interval of conducted beats is constant. What is the rhythm?

Answer: Second-degree AV block, Mobitz type II

2:1 conduction with a constant PR interval on conducted beats and non-conducted P waves is consistent with Mobitz type II second-degree AV block.

In transcranial Doppler (TCD), the middle cerebral artery (MCA) is most commonly insonated through which acoustic window?

Answer: Transtemporal window

The transtemporal window, located superior to the zygomatic arch, provides the primary access for MCA insonation in TCD.

Which B-mode gray-scale finding suggests CHRONIC rather than acute DVT?

Answer: Echogenic, retracted thrombus with partial recanalization

Chronic DVT typically appears echogenic (bright) and contracted, often with partial recanalization channels visible on color Doppler.

What is the normal range for mitral valve area (MVA) as measured by the pressure half-time (PHT) method?

Answer: 4.0–6.0 cm²

Normal MVA is 4.0–6.0 cm²; severe mitral stenosis is defined as MVA ≤1.5 cm², with MVA = 220/PHT.

Which autonomic receptor mediates the positive chronotropic (rate-increasing) effect of catecholamines on the SA node?

Answer: Beta-1 adrenergic receptor

Beta-1 adrenergic receptors predominate in the SA node; stimulation by norepinephrine or epinephrine increases the rate of spontaneous depolarization, raising heart rate.

In tricuspid regurgitation severity assessment, a vena contracta width of >7 mm indicates:

Answer: Severe tricuspid regurgitation

A vena contracta width greater than 7 mm is a specific marker of severe tricuspid regurgitation by ASE 2017 guideline criteria.

Which of the following best describes the relationship between transducer frequency, image resolution, and penetration depth?

Answer: Higher frequency improves resolution but decreases penetration.

There is a fundamental trade-off in ultrasound physics between image resolution and penetration. Higher frequency transducers produce shorter wavelengths, which provide better axial and lateral resolution (finer detail). However, higher frequency sound waves are attenuated more rapidly by tissue, which limits their ability to penetrate to deeper structures.

When scanning the popliteal fossa from a posterior approach, what is the typical anatomical relationship between the popliteal vein and the popliteal artery on the ultrasound screen?

Answer: The vein is superficial (closer to the transducer) to the artery

When imaging from the posterior aspect of the knee (the popliteal fossa), the popliteal vein is typically located superficial to the popliteal artery. Therefore, on the ultrasound display, the vein will appear closer to the top of the screen than the artery.

During transseptal puncture, which anatomical landmark is used to confirm correct needle position before puncture?

Answer: The 'tenting' of the fossa ovalis observed on fluoroscopy and confirmed by pressure monitoring

Tenting of the fossa ovalis seen fluoroscopically and confirmed by a right atrial pressure waveform at the needle tip confirms correct positioning before transseptal puncture.

Which stress testing parameter is most predictive of cardiac mortality independent of angiographic findings?

Answer: Exercise capacity in METs

Exercise capacity measured in METs is one of the strongest independent predictors of cardiac and all-cause mortality across multiple studies.

What is the normal resting systemic vascular resistance (SVR) range in dynes·sec·cm⁻⁵?

Answer: 800–1200

Normal SVR is approximately 800–1200 dynes·sec·cm⁻⁵, representing the afterload against which the left ventricle pumps.

Which artifact on echocardiography is caused by two strong specular reflectors and produces a false image at twice the true depth of a structure?

Answer: Reverberation artifact

Reverberation artifacts occur when the ultrasound beam bounces repeatedly between two strong reflectors, generating false echoes at multiples of the true depth.

In duplex evaluation of suspected upper extremity DVT, which vein is MOST commonly affected by catheter-related thrombosis?

Answer: Subclavian or axillary vein

Catheter-related upper extremity DVT most commonly involves the subclavian or axillary vein due to central line placement routes.