10.6 Acute Ischemic and Hemorrhagic Stroke in the Cardiac Patient

Why Stroke Belongs in a Cardiac Medicine Exam

Test-plan item II.D.1 sits inside the 23%-weighted Non-Cardiovascular Conditions domain, and on the CMC the question is never "manage the stroke" — it is "recognize the stroke in a patient whose heart put it there, and protect the brain while the cardiac problem is still active." Roughly one in five to one in three ischemic strokes is cardioembolic, and cardioembolic infarcts are disproportionately large, cortical, and disabling because a cardiac embolus is a formed clot that lodges proximally rather than a platelet-fibrin fragment from a carotid plaque.

Cardioembolic Sources You Will See on a Cardiac Unit

Recognition: The Hard Part Is the Sedated Patient

The National Institutes of Health Stroke Scale (NIHSS) is an 11-item, 0–42 examination covering level of consciousness and orientation, gaze, visual fields, facial palsy, motor arm and leg, limb ataxia, sensation, language, dysarthria, and extinction/inattention. A score of 6 or more raises suspicion for large-vessel occlusion (LVO), which is the population that benefits from thrombectomy. Learn the scale as a communication tool: the number you report drives whether interventional neuroradiology is activated.

Last known well (LKW) — not "time found" — starts every clock. If a patient with new AF was neurologically intact at the 0200 assessment and is aphasic at 0600, LKW is 0200. Documenting a genuine neurologic assessment every shift, and after every procedure, is what preserves the window.

The cardiac unit's specific problem is the patient who cannot be examined conventionally:

• Post-arrest or post-cardiac-surgery patients on sedation. Asymmetry, not level of consciousness, is the signal. A unilateral gaze preference, an asymmetric grimace to noxious stimulus, unilateral flaccidity, or a new anisocoria in a sedated patient is a stroke until CT proves otherwise. Advocate for a sedation hold to examine.
• Intubated patients. Language items are untestable; grade motor, gaze, fields by threat, and facial symmetry.
• Post-catheterization patients whose deficit is attributed to "residual sedation" — the single most common cause of a missed window on a cardiac floor.
• Post-arrest patients, in whom global anoxic injury and focal embolic stroke coexist; a focal deficit is never explained away as anoxia without imaging.

Door-to-CT should be 20 minutes or less and door-to-needle 60 minutes or less (many centers now target 45 minutes or less). Call the stroke alert on suspicion; do not wait for a full NIHSS.

Imaging Pathway and Treatment Windows

Non-contrast head CT first, always — its only job in the hyperacute phase is to exclude hemorrhage, because thrombolysis into an intracerebral hemorrhage (ICH) is lethal. Early ischemic change on CT is subtle (loss of gray-white differentiation, insular ribbon sign, hyperdense MCA sign) and its absence does not exclude infarct. CT angiography (CTA) of the head and neck identifies the occluded vessel and the collateral circulation; CT perfusion or MR diffusion-perfusion defines the ischemic core versus the salvageable penumbra and is what extends the thrombectomy window past 6 hours.

Blood Pressure Targets — Memorize These

First-line agents for the pre-lytic and post-lytic ceiling are labetalol 10–20 mg IV push over 1–2 minutes, repeatable, or a nicardipine infusion at 5 mg/h titrated by 2.5 mg/h every 5–15 minutes to a maximum of 15 mg/h; clevidipine is an alternative. Nitroprusside is reserved and disfavored because it raises intracranial pressure and carries cyanide/thiocyanate risk. If blood pressure cannot be brought under 185/110 mmHg, the patient is not a lytic candidate — do not give the drug and keep pushing antihypertensives past target.

Thrombolysis Contraindications That Cardiac Patients Actually Have

• Anticoagulation. Warfarin with INR greater than 1.7 (or PT greater than 15 seconds) excludes lysis. A direct oral anticoagulant (DOAC) taken within the last 48 hours excludes lysis unless a sensitive assay (anti-Xa level, dilute thrombin time, ecarin clotting time) is normal. Treatment-dose low-molecular-weight heparin within 24 hours excludes lysis. Prophylactic-dose heparin does not.
• Active infective endocarditis — absolute. Lysing an embolus from a vegetation frequently produces hemorrhagic conversion or rupture of a mycotic (septic) aneurysm. This is a favorite CMC distractor: fever, murmur, splinter hemorrhages, and a hemiparesis is a thrombectomy or medical-management case, never a lytic case.
• Aortic dissection — absolute. A dissection flap occluding a carotid presents as stroke; the tearing pain, pulse or blood pressure differential and widened mediastinum must be sought.
• Recent major surgery within 14 days, including cardiac surgery, is a strong relative contraindication; recent intracranial or spinal surgery within 3 months is absolute.
• Recent myocardial infarction within 3 months is relative; risk of myocardial rupture and hemopericardium rises with a recent large STEMI.
• Platelets under 100,000/microliter, glucose under 50 mg/dL (correct and re-examine — hypoglycemia is a stroke mimic), known intra-axial neoplasm, prior ICH, and active internal bleeding.

Post-Thrombolysis Nursing Protocol

The 24 hours after a lytic are a nursing protocol, not a physician order set.

1. Vital signs and neurologic checks: every 15 minutes during the infusion and for 2 hours after it starts, then every 30 minutes for 6 hours, then hourly through hour 24.
2. Blood pressure maintained under 180/105 mmHg for the full 24 hours. Have labetalol or a nicardipine drip at the bedside before the lytic is hung, not after the pressure rises.
3. No antithrombotics for 24 hours — no aspirin, no clopidogrel, no therapeutic heparin, no DOAC — until a 24-hour follow-up CT excludes hemorrhage. This directly collides with the cardiac reflex to load dual antiplatelet therapy, and it is a high-yield exam trap.
4. Avoid invasive procedures for 24 hours where possible: no nasogastric tube, no indwelling urinary catheter, no arterial or central line placement, no non-compressible arterial puncture.
5. Recognize symptomatic intracranial hemorrhage: any acute neurologic deterioration, new severe headache, nausea and vomiting, acute hypertension, or a sudden NIHSS increase of 4 or more points. The response is a fixed sequence — stop the infusion immediately, obtain a STAT non-contrast head CT, send PT/INR, aPTT, platelets, fibrinogen and a type and crossmatch, notify the stroke team and neurosurgery, and prepare cryoprecipitate 10 units (fibrinogen goal above 150–200 mg/dL) plus tranexamic acid 1,000 mg IV over 10 minutes or aminocaproic acid per protocol.
6. Continuous cardiac monitoring for at least 24 hours — new AF is detected in a meaningful minority of "cryptogenic" strokes and changes secondary prevention entirely.

Permissive Hypertension — Fighting the Cardiac Reflex

In a patient who did not receive lysis, the ischemic penumbra is perfused by collaterals whose flow is pressure-dependent because autoregulation is lost. Lowering blood pressure enlarges the infarct. The cardiac nurse's trained instinct — see 200/105 mmHg, treat 200/105 mmHg — is actively harmful here. Do not treat unless blood pressure exceeds 220/120 mmHg, and then reduce it by no more than 15% over 24 hours. The exceptions are the competing cardiac emergencies: aortic dissection, active ischemia, acute pulmonary edema, and the post-thrombectomy patient whose interventionalist sets a lower ceiling to prevent reperfusion hemorrhage.

Intracerebral Hemorrhage and Reversal

An anticoagulated cardiac patient with a sudden headache, vomiting, decreased level of consciousness and a rising blood pressure has an ICH until proven otherwise. Reversal is time-critical and agent-specific:

Other ICH priorities: head of bed 30 degrees, normothermia, glucose control, seizure treatment (but not prophylaxis), reversal of the coagulopathy before the CT is repeated, and blood pressure toward SBP 140 mmHg when presenting SBP is 150–220 mmHg.

Secondary Prevention and Supportive Care

Timing of anticoagulation after cardioembolic stroke is the balance between recurrent embolism and hemorrhagic transformation. The classical teaching is the 1-3-6-12 rule — start on day 1 for transient ischemic attack, day 3 for a small infarct, day 6 for a moderate infarct, day 12 for a large infarct — with recent randomized data supporting earlier initiation (roughly within 48 hours for minor and moderate strokes and around day 6–7 for large strokes). Know the principle: infarct size and hemorrhagic transformation drive the timing, not a fixed calendar.

• LV thrombus after anterior MI: anticoagulate for 3–6 months with a vitamin K antagonist (INR 2.0–3.0) as the best-established option, with repeat echocardiography to document resolution.
• Left atrial appendage occlusion (a WATCHMAN FLX or Amulet device) is for AF patients with a long-term contraindication to oral anticoagulation; post-implant patients still need a defined antithrombotic course and a 45-day TEE.
• PFO closure is reasonable for cryptogenic stroke in patients roughly 18–60 years old with a high-risk PFO and no other identified mechanism.
• Blood pressure control, high-intensity statin, glycemic control, and smoking cessation are the shared backbone with coronary secondary prevention.

The Supportive Care That Prevents the Second Insult

• Dysphagia screen before anything by mouth — including oral medications and ice chips. Failure means NPO plus a speech-language pathology evaluation. Aspiration pneumonia is a leading cause of post-stroke death and it is a nursing-preventable event.
• Venous thromboembolism prophylaxis: intermittent pneumatic compression from admission; pharmacologic prophylaxis is added after 24 hours in ischemic stroke once bleeding is excluded.
• Glucose 140–180 mg/dL. Hyperglycemia enlarges the infarct; hypoglycemia mimics stroke.
• Treat fever aggressively — every 1 degree Celsius above normal worsens outcome. Use acetaminophen and surface cooling and look for the source (endocarditis, aspiration, line infection).
• Avoid hypotonic and dextrose-containing fluids; isotonic saline is the maintenance fluid of choice because free water worsens cerebral edema.
• Head of bed flat to 30 degrees per protocol, early mobilization once stable, and swallow-safe medication routes for the cardiac drugs the patient still needs.