Cardiovascular Disease - Heart Failure & Cardiogenic Shock

Types of hemodynamic monitoring

• Pulmonary artery catheter (PAC) or Swan-Ganz catheter

• Central venous pressure catheter

• Arterial artery catheter

  
  

Pulmonary Artery Catheter (PAC)

Used to:

• Evaluate cardiac function

• Help diagnose the cause (etiology) of shock

• Evaluate response to:

  • Fluids

  • Medications/interventions

• Monitor cardiac pressures

Pulmonary Artery Catheter (PAC) - Central Venous Pressure (CVP)

• Normal: 2–6 mm Hg

• Helps evaluate:

  • Fluid status

  • Right-sided heart function

• ↑ CVP → may indicate fluid overload or right-sided heart failure

Pulmonary Artery Catheter (PAC) - Pulmonary Artery Occlusion Pressure (PAOP)

• Normal: 6–12 mm Hg

• Also called pulmonary wedge pressure

• Helps evaluate:

  • Fluid balance

  • Left ventricular function

• ↓ PAOP → may indicate low fluid volume

• ↑ PAOP → may indicate left ventricular dysfunction/left-sided heart failure

Pulmonary Wedge Pressure

How it is obtained:

• Inflate the balloon briefly

• Pressure appears on the monitor

• Immediately deflate the balloon

• Do NOT leave the balloon inflated.

• Prolonged inflation can cause pulmonary artery rupture.

PAC or CVP Access Sites

• Internal jugular vein **

• External jugular vein

• Subclavian vein

• Femoral vein

• Basilic vein

Central Venous Pressure (CVP)

• Central line → enters the central venous circulation:

  • SVC

  • IVC

  • Right atrium (RA)

• Useful for assessing fluid volume status and preload

  • Less precise/rapid than the pulmonary artery system

• No valves between the vena cava and right atrium → pressure reflects CVP

• Allows for rapid, high-volume fluid resuscitation

• Allows for frequent blood draws

• CVP can be monitored:

  • Continuously

  • Intermittently

    • Fluids can run through the port when a CVP reading is not being obtained

Central Line Uses

• Administer medications

• Administer fluids

• Monitor CVP

• Evaluate fluid volume status

• Obtain blood samples

• Provide continuous IV access

• Catheter is inserted through a large vein and advanced toward the right atrium.

Arterial Line

Provides:

• Continuous blood pressure monitoring

• Arterial blood pressure readings

• Access for arterial blood samples/ABGs

Arterial Line - Before Insertion

• Perform an Allen's test

  • Checks circulation to the hand/fingers

• Assess:

  • Capillary refill

  • Sensation

  • Skin color

  • Skin temperature

  • Pulses

Arterial Line - Catheter/Site Care

• Maintain appropriate dressing and perform dressing changes as needed.

• Immobilize the body part where the catheter is placed in a neutral position.

  • Prevent joint flexion or extension

• Perform ROM of the hand/fingers

  • Do not hyperextend the wrist → risk of neuromuscular injury

• Assess the site every 1 hour for:

  • Redness

  • Drainage

  • Bruising

  • Blanching

  • Pallor

  • Firmness

  • Swelling

• Assess distal circulation:

  • Skin color

  • Temperature

  • Capillary refill time (CRT)

  • Distal pulses

  • Motor function

  • Sensory function

Removing an Arterial Catheter

• Apply direct pressure for approximately 5 minutes

• Helps prevent bleeding.

Complications from Heart Disease

• Heart Failure

• Cardiogenic Shock

Heart Failure (HF)

• Inability of the heart to pump enough blood to meet the body's needs for oxygen and nutrients

• A syndrome characterized by:

  • Fluid overload or

  • Inadequate tissue perfusion

• Involves a problem with:

  • Systolic failure → problem with heart contraction/pumping

  • Diastolic failure → problem with heart filling

• Some cases of heart failure are reversible

• Most HF is a progressive, lifelong disorder

  • Managed with lifestyle changes and medications

HF Causes

• CAD

• Hypertension

• Cardiomyopathy

• Valvular disorders

• Renal dysfunction

Heart Failure — Diagnosis: Echocardiogram

• Evaluates cardiac function

• Measures ejection fraction (EF)

• EF <40% → impaired left ventricular systolic function

Heart Failure — Diagnosis: B-type Natriuretic Peptide (BNP)

• Laboratory value associated with heart failure

• Secreted by the ventricles

• Released in response to increased pressure/stretch

• ↑ BNP → may indicate heart failure or worsening heart failure

• BNP >100 → suggestive of heart failure

Heart Failure — Diagnosis: Symptomatology

Patient's signs and symptoms are also used when diagnosing HF

Heart Failure — Types & Classifications

Types

• Acute HF → develops suddenly

• Chronic HF → develops gradually and persists over time

• Acute-on-chronic HF → sudden worsening of pre-existing chronic HF

Heart Failure Classifications

1. NYHA (New York Heart Association)

• Class I–IV

• Based on how much physical activity causes symptoms

2. ACC/AHA

• Stage A–D

• Based on the progression of heart failure and risk/structural disease

Left-Sided Heart Failure

• LV failure → left ventricle cannot pump effectively

• Blood backs up into the lungs

• Causes pulmonary congestion

• Left = Lungs

Left HF Clinical Manifestations:

• Dyspnea / SOB → shortness of breath

• DOE → dyspnea on exertion

• Cough

• Crackles

• PND → paroxysmal nocturnal dyspnea (waking up at night short of breath)

• ↓ O₂ / hypoxemia

• S3 heart sound

Right-Sided Heart Failure

• RV failure → right ventricle cannot pump effectively

• Blood backs up into the systemic circulation

• Causes systemic congestion

• Right = Rest of the body

Right HF Clinical Manifestations:

• Peripheral edema → swelling, especially legs/feet

• JVD → jugular venous distention

• Hepatomegaly → enlarged liver

• Ascites → fluid accumulation in the abdomen

• Anorexia / nausea

• Weakness

• Weight gain → usually from fluid retention

Left vs Right HF

Left HF

Right HF

1. Myocardial dysfunction

• → Heart muscle is not working properly

• → ↓ Cardiac output

2. ↓ Cardiac output

• → Kidneys receive less blood

• → ↓ Renal blood flow

3. ↓ Renal blood flow

• → Renin release

• → ↑ Angiotensin II

4. Angiotensin II

• → Vasoconstriction → ↑ resistance/workload on the heart

• → Stimulates aldosterone

5. Aldosterone

• → Kidneys retain sodium + water

• → ↑ Blood volume

• → ↑ Venous return (preload)

• → Edema

6. ↓ Cardiac output also activates the sympathetic nervous system

• → ↑ Heart rate and force of contraction

• → Initially helps maintain cardiac output

• → But increases cardiac workload and oxygen demand

7. Increased blood volume + vasoconstriction + increased cardiac work

• → ↑ Cardiac workload

• → Further myocardial dysfunction

Heart Failure — Nursing Diagnoses

• Activity intolerance and fatigue

  • Related to decreased cardiac output and reduced oxygen delivery

• Excess fluid volume

  • Related to sodium and water retention

  • May cause edema, weight gain, crackles, and congestion

• Anxiety

  • Related to symptoms, illness, and uncertainty about condition

• Powerlessness

  • Related to the chronic nature of heart failure and changes in lifestyle

• Noncompliance

  • Difficulty following the prescribed medications, diet, fluid restriction, or activity plan

Heart Failure — Nursing Management

• Provide symptom relief

• Monitor for dysrhythmias

• Hemodynamic monitoring

• Monitor fluid status

  • I&O

  • Daily weights

  • Assess for edema

• Provide psychosocial support

Heart Failure — Medications

• ACE inhibitors

  • ↓ Blood pressure

  • ↓ Afterload

  • ↓ Cardiac workload

  • Help prevent/worsen remodeling

• ARBs

  • Block the effects of angiotensin II

  • ↓ Vasoconstriction

  • ↓ Blood pressure

  • ↓ Cardiac workload

• Beta blockers

  • ↓ Heart rate

  • ↓ Contractility

  • ↓ O₂ demand

  • Decrease cardiac workload

• Diuretics

  • Remove excess fluid and sodium

  • ↓ Fluid volume

  • ↓ Edema and pulmonary congestion

  • ↓ Preload

• Digitalis (Digoxin)

  • Increases the force of cardiac contraction

  • Helps improve cardiac output

  • Slows heart rate

Heart Failure — IV Infusions

• Dobutamine (Dobutrex)

  • Increases cardiac contractility

  • Helps increase cardiac output

  • Used for acute/severe heart failure when increased cardiac pumping is needed

• Milrinone (Primacor)

  • Increases cardiac contractility

  • Causes vasodilation

  • ↑ Cardiac output

  • ↓ Cardiac workload/vascular resistance

ICD — Implantable Cardioverter-Defibrillator

• Recommended for patients with heart failure who are at high risk for:

  • Ventricular tachycardia (VT)

  • Ventricular fibrillation (VF)

• The ICD detects dangerous ventricular rhythms

• It can deliver an electrical shock to terminate the rhythm

• Helps prevent sudden cardiac death/cardiac arrest.

LifeVest

• LifeVest = wearable cardioverter-defibrillator (WCD)

• Used for high-risk heart failure patients who are at risk for dangerous ventricular dysrhythmias.

• It is an external defibrillator worn by the patient.

• Can serve as a temporary alternative/bridge to an ICD when an implanted device is not immediately available or appropriate.

• The LifeVest can detect dangerous rhythms and deliver a shock to restore a normal rhythm.

Intra-Aortic Balloon Pump (IABP)

• Circulatory assist device

• ↓ workload of the heart during contractions but does not perform the actual pumping work of the heart.

• Consists of a catheter with a balloon at the distal end.

• Balloon is positioned in the descending aorta.

• Uses counterpulsation:

  • Balloon inflates and deflates according to the cardiac cycle

  • This helps augment the pumping action of the heart.

• Synchronized with the ECG or arterial blood pressure (ABP) to identify systole and diastole and time balloon inflation/deflation.

• Supports a failing LV by mechanically displacing blood within the aorta.

Effects of the IABP

• Increases oxygen-rich blood supply to the myocardium

  • Balloon inflates during diastole

  • → pushes blood toward the coronary arteries

  • → ↑ coronary perfusion

• Decreases myocardial oxygen demand

  • Balloon deflates just before systole

  • → ↓ resistance/afterload against the LV

  • → ↓ LV workload

  • → ↓ myocardial oxygen demand

IABP: Common Uses

Treatment of pump failure:

• Cardiogenic shock → heart cannot pump enough blood to meet the body's needs.

• Intraoperative MI → MI occurring during surgery.

• Low cardiac output after bypass surgery → heart is not pumping effectively after cardiopulmonary bypass.

Other uses:

• Weaning from cardiopulmonary bypass → provides temporary LV support while the heart resumes effective pumping.

• Cardiomyopathies → supports the heart when severe myocardial dysfunction causes inadequate cardiac output.

IABP: Complications

• Infection

  • Risk from the catheter insertion site.

• Ischemia

  • Reduced blood flow to the femoral, renal, visceral, or spinal arteries.

  • Can occur because the catheter/balloon obstructs arterial blood flow.

• Embolic shower

  • Microscopic clots/debris can form on the balloon and travel through the bloodstream.

  • Can cause:

    • Peripheral thrombosis

    • Myocardial ischemia

    • Hemodynamic decompensation

    • Late pseudoaneurysm

• Balloon/mechanical failure

  • Balloon can malfunction or rupture.

  • Balloon rupture requires removal of the IABP, with surgical/vascular expertise as needed.

• Aortic dissection

  • Tear in the aortic wall.

  • Can lead to hemorrhage into the mediastinum.

• Cerebral embolism

  • Embolic material can travel to the brain, particularly during insertion.

  • → Possible neurologic injury/stroke.

• Compartment syndrome

  • Increased pressure within a limb compartment can compromise blood flow and nerves.

Cardiogenic Shock

• Life-threatening condition with a high mortality rate.

• Occurs when the heart cannot pump enough blood to meet the body's needs.

Cardiogenic Shock - Causes

• Myocardial infarction (MI)

• Heart failure (HF)

• Cardiac tamponade

• Pulmonary embolism (PE)

• Cardiomyopathy

• Dysrhythmias/arrhythmias

Cardiogenic Shock: Pathophysiology

• Heart is unable to pump effectively

• ↓ Cardiac output

• ↓ Tissue perfusion

• ↓ Oxygen delivery to tissues

• Tissue hypoxia

• Cells switch to anaerobic metabolism

• ↑ Lactic acid → metabolic acidosis

• Poor perfusion causes organ dysfunction

• Continued poor cardiac function → worsening shock

Compensation:

• Sympathetic nervous system activates → ↑ HR and vasoconstriction

• This temporarily helps maintain BP, but increases the heart’s workload and oxygen demand.

• The heart becomes too weak to pump enough blood, often due to severe heart damage such as an MI.

• Cardiac output decreases, so less blood reaches the body's tissues and organs.

• Oxygen delivery decreases, causing tissue hypoxia.

• Cells switch to anaerobic metabolism because they do not receive enough oxygen.

• Lactic acid builds up, causing metabolic acidosis.

• Continued poor perfusion causes organ dysfunction and eventually organ failure.

Cardiogenic Shock: Clinical Manifestations

• symptoms of heart failure

• shock state

• hypoxia

Cardiogenic Shock: Clinical Manifestations

• Decreased cardiac output (CO)

  • Low blood pressure → systolic BP <85 mmHg

  • Tachycardia → heart beats faster to try to maintain cardiac output

  • Rapid, weak/thready pulse

  • Acidosis → poor tissue perfusion causes lactic acid buildup

• Poor peripheral perfusion

  • Cool, clammy skin

  • Decreased peripheral pulses

• Kidney dysfunction

  • Renal insufficiency

  • Decreased urine output because the kidneys receive less blood flow

• Pulmonary edema

  • Fluid backs up into the lungs because the failing LV cannot pump blood forward effectively.

  • ↑ PAOP → indicates increased left-sided filling pressure

  • ↑ CVP → may occur as heart failure progresses and right-sided pressures increase

• Loss of consciousness

  • Severe decrease in brain perfusion/oxygen delivery can cause altered mental status or loss of consciousness.

Cardiogenic Shock: Treatment

• Correct the underlying cause

  • Treat what caused the cardiogenic shock, such as MI, dysrhythmia, or heart failure.

• Decrease the heart's workload

  • Reduce the heart's oxygen demand and workload.

• Improve oxygenation and cardiac output

  • Diuretics → remove excess fluid and decrease pulmonary congestion.

  • Positive inotropes → increase the strength of heart contractions → ↑ cardiac output.

  • Vasopressors → increase vascular tone and help maintain blood pressure and organ perfusion when hypotension is severe.

• Intra-aortic balloon pump (IABP)

  • Provides temporary support to the failing LV.

  • ↓ myocardial workload and oxygen demand

  • ↑ coronary perfusion.