Stress Testing Protocols Flashcards

A 65-year-old woman with left bundle branch block (LBBB) is referred for stress testing. Which modality is most appropriate?

Answer: Vasodilator nuclear stress test (adenosine or regadenoson)

LBBB causes septal wall motion abnormalities and ST changes that make ECG-based exercise stress tests uninterpretable; vasodilator nuclear imaging is preferred to avoid false positives.

What is the formula for calculating maximum predicted heart rate (MPHR) in adults?

Answer: 220 minus age

The most widely used formula for MPHR is 220 minus the patient's age in years, though alternative formulas exist for specific populations.

Which symptom endpoint during stress testing would be classified as angina equivalent rather than typical angina?

Answer: Jaw tightness and shortness of breath without chest pain

Angina equivalents are ischemic symptoms that occur without classic chest pain, such as jaw pain, exertional dyspnea, or arm heaviness, and carry the same clinical significance.

In pediatric stress testing for evaluation of congenital heart disease, the Bruce protocol is often modified by:

Answer: Adding a preliminary Stage 0 (1.7 mph, 0% grade) and Stage 0.5 (1.7 mph, 5% grade)

Pediatric or deconditioned patients benefit from adding pre-Stage 1 warm-up stages at low speed and minimal grade before the standard Bruce protocol begins.

A patient on a beta-blocker achieves only 75% of MPHR but develops 2 mm horizontal ST depression with typical angina. The stress test result should be interpreted as:

Answer: Positive for ischemia despite submaximal effort

Significant ST depression (≥1 mm) with typical anginal symptoms constitutes a positive test even if the 85% MPHR target was not achieved.

What is the primary hemodynamic mechanism by which regadenoson induces myocardial ischemia in pharmacologic stress testing?

Answer: It causes heterogeneous coronary vasodilation, producing a coronary steal phenomenon in stenosed vessels

Regadenoson is an A2A adenosine receptor agonist that maximally dilates normal coronary arteries; stenosed vessels cannot dilate equivalently, causing relative hypoperfusion (coronary steal).

Which blood pressure response during exercise is considered hypertensive and may require test termination?

Answer: SBP exceeds 250 mmHg or DBP exceeds 115 mmHg

A systolic BP >250 mmHg or diastolic BP >115 mmHg during exercise are relative indications to terminate the stress test due to risk of cardiovascular events.