CCRN Cardiovascular Review (13%): Dysrhythmias, ACS, Tamponade, and Hypertensive Crisis

What the cardiovascular category covers on the CCRN exam

Cardiovascular is 13% of the Adult CCRN Test Plan that applies to exams taken on and after November 12, 2025. AACN publishes percentages, not item counts, so any count is an estimate: 13% of the 125 scored items is about 16 questions (Passy estimate). The category was 17% under the 2020 test plan, and the 2025 list places acute pulmonary edema under Respiratory rather than here.

The test plan pairs the 16 listed problems with "testable nursing actions." For this category they are interpreting and responding to cardiac rhythms, monitoring hemodynamic status, recognizing early signs of falling cardiac output, and caring for patients who need catheterization, endovascular procedures, mechanical circulatory support, invasive or noninvasive hemodynamic monitoring, pericardiocentesis or temporary pacing.

A note on editions. AACN validates each exam item against at least one reference on its bibliography, and the Adult bibliography still lists the 2020 AHA Guidelines for CPR and ECC. This page teaches from the 2025 AHA guidelines. If your review book and this page disagree on a rhythm point, check which edition each one follows.

Stable or unstable: the first question in a CCRN rhythm item

Decide whether the rhythm is causing instability before you name it. Part 9 of the 2025 AHA Guidelines (Adult Advanced Life Support) lists hypotension, acutely altered mental status, signs of shock, chest pain and acute heart failure as signs of instability with a narrow-complex tachycardia (NCT). For a wide-complex tachycardia (WCT), its examples are a systolic pressure below 80 mm Hg or altered mentation. There is a second condition: the tachycardia must plausibly be the cause of the instability, not a response to another illness such as sepsis.

For the exam, the nurse's part is recognition and readiness: identify the instability, call for help, and have the defibrillator ready in synchronized mode when cardioversion is the next step. The table gives no doses on purpose. Doses belong to your unit's protocol and the provider's order.

Two patients, one alarm (fictional). In bed 4, a 58-year-old woman two days after a bowel resection develops a sudden, regular narrow tachycardia at about 180/min. Her blood pressure is 118/74 mm Hg, she is alert, and she reports palpitations without chest pain. None of the AHA instability signs is present, so she is stable: vagal maneuvers and adenosine are the first options, and cardioversion waits until they fail.

In bed 9, a 66-year-old man with pneumonia has a temperature of 39.4 °C, a sinus tachycardia of 138/min and a blood pressure of 92/50 mm Hg. He is hypotensive, but the rhythm is a response to the infection, not its cause. Cardioversion would treat nothing here. The work is sepsis care, which the CCRN sepsis and shock guide lays out.

The free CCRN set includes a third version of this decision: a post-operative patient whose sudden narrow-complex tachycardia comes with low pressure and new confusion. When the table makes sense, test the unstable narrow-complex tachycardia decision in the free CCRN set → and read why each other option falls short.

Acute coronary syndrome: what to recognize first

The MSD Manual's overview of acute coronary syndromes (reviewed July 2026), which cites the 2025 ACC/AHA ACS guideline, separates the three syndromes by symptoms, ECG findings and cardiac troponin:

• Unstable angina: symptoms of myocardial ischemia without evidence of acute myocardial infarction on the clinical assessment and serial troponin testing.
• NSTEMI: acute myocardial injury, shown by a rise or fall in troponin with at least one value above the assay's 99th-percentile upper reference limit, together with evidence of ischemia, without persistent diagnostic ST elevation. An elevated troponin alone is not enough.
• Suspected STEMI: an ischemic presentation with diagnostic ST elevation or a recognized occlusion-equivalent ECG pattern requires urgent reperfusion assessment. Do not wait for troponin confirmation or use the response to nitroglycerin to decide whether the ECG is an emergency.

Two time targets from the same source are worth knowing. The ECG should be done as soon as possible, within 10 minutes of presentation to medical care. For STEMI, emergency PCI is the choice when door-to-balloon time is under 90 minutes, or 120 minutes when the patient is transferred between hospitals. At the bedside that means getting the 12-lead fast, comparing it with any earlier tracing, and watching the ST segments continuously. AACN keeps a Practice Alert on this, "Ensuring Accurate ST-Segment Monitoring."

Cardiac tamponade after heart surgery: a worked vignette

The MSD Manual's pericarditis chapter (reviewed April 2026) describes tamponade findings that resemble cardiogenic shock (low cardiac output, low arterial pressure, tachycardia, dyspnea), and often includes distended neck veins. Venous distension is not unique to tamponade and can also occur with right-sided or biventricular pump failure. Severe tamponade is nearly always accompanied by pulsus paradoxus, an inspiratory fall in systolic pressure of more than 10 mm Hg, and the heart sounds are muffled unless the effusion is small. On a pulmonary artery catheter, diastolic pressures are elevated and roughly equal in all chambers and in the pulmonary artery.

A fictional patient. Six hours after mitral valve repair, a 71-year-old man's heart rate climbs from 92 to 126/min over an hour. His blood pressure falls from 108/64 to 84/62 mm Hg, his CVP rises from 8 to 16 mm Hg, and the pulmonary artery diastolic and wedge pressures now sit within a couple of points of the CVP. His neck veins are distended and his heart sounds are harder to hear than at the start of the shift.

Read the pattern, not one number:

1. Filling pressures are rising while pressure and output fall. That combination points to a heart that cannot fill, not to fluid overload. The MSD Manual's critical care monitoring chapter notes that tamponade lowers cardiac output by reducing venous return and preload, so a diuretic or vasodilator aimed at the CVP number would work against him.
2. The diastolic pressures are converging. Near-equal pressures across the chambers are the catheter's tamponade signature.
3. Small volumes matter after surgery. MSD notes that rapid accumulation of as little as about 150 mL can cause tamponade. It also warns that a loculated effusion or a localized clot may compress only some chambers, so the classic signs can be missing.
4. It is a clinical diagnosis. When tamponade is suspected, echocardiography is done unless even a brief delay could be life threatening, and then the fluid is drained immediately.

The nursing priority is to notify the surgeon now, stay with the patient, and prepare for emergency decompression as the team directs.

Hypertensive emergency: the first-hour arithmetic

Section 6.2 of the 2025 AHA/ACC high blood pressure guideline defines a hypertensive emergency as blood pressure above 180/120 mm Hg with evidence of acute target-organ damage, and recommends ICU admission (class 1). How far to lower the pressure in the first hour depends on whether a compelling condition is present.

The guideline's reason for going slowly is autoregulation: in long-standing hypertension, a rapid return to normal can leave vital organs underperfused. Its supportive text adds that continuous infusions of short-acting, titratable agents are often preferable in the ICU. Stroke and pregnancy follow separate sections, and the CCRN neuro review covers the 2026 stroke targets.

Worked example (fictional). A 63-year-old arrives at 232/128 mm Hg with new acute kidney injury. Imaging shows no aortic dissection, there is no stroke, and she is not pregnant, so no compelling condition applies.

• 25% of 232 is 58.
• 232 − 58 = 174, so the first-hour goal is a systolic pressure no lower than about 174 mm Hg.
• If she stays stable, the next step is below 160/100 within 2 to 6 hours, then 130–140 systolic over the following 24 to 48 hours.

Had the scan shown an aortic dissection, the same reading would call for a systolic below 120 mm Hg within the hour. The patient's diagnosis, not the height of the number, sets the target. To check the rule on a new set of numbers, try the first-hour blood pressure goal item in the mixed CCRN set →. Then see how this category fits with the others in the CCRN (Adult) test plan guide.