S1W7 ACP Right Heart Cath AM

Right Heart Catheterization Overview:

  • Purpose: Right heart catheterization (RHC) provides essential hemodynamic data for diagnosing cardiovascular conditions.

  • Key Tools: Involves cardiac catheterization and angiography.

Educational Objectives :

  • Understand the history and development of RHC.

  • Learn to perform and interpret right heart studies.

  • Identify the indications for using RHC as a diagnostic tool.

History of RHC :

  • First performed on a horse by Claude Bernard (1844).

  • First human RHC by Werner Forssmann (1929).

    • Technique involved self-catheterization via left antecubital vein.

Indications for RHC :

  • Measurement of cardiac output.

  • Assessment of intracardiac pressures and shunts.

  • Evaluation of pulmonary hypertension (PH).

  • Diagnosis of valvular disease.

  • Historical role in cardiogenic shock evaluation.

Contraindications for RHC :

  • Absolute Contraindications:

    • Mechanical tricuspid/pulmonic valve

    • Right heart masses (thrombus/tumor)

    • Right-sided endocarditis

  • Relative Contraindications:

    • Coagulopathy - blood clotting disorder

    • Pacemaker presence

    • Skin site infections

    • Bioprosthetic tricuspid or pulmonic valve

    • LBBB

    • Arrhythmias

Procedure of RHC :

  • Preparation:

    • Calibrate oximeter

    • check hemoglobin (Hb)

    • setup ECG and saturation probe.

    • set up saline / pressure bag

    • Align transducer with reference point for pt - mid chest inline with approx RA

    • Open transducer to air and zero - close transducer once zeroed

    • WHO checklist

    • Provide operator with correct equipment : sheath, guidewire, cath

  • Access: Predominantly via femoral vein; alternative access through brachial, internal jugular, or subclavian veins.

Key Measurements :

  • Hemodynamic :

    • Record phasic and mean pressures.

    • Advanced catheter placement into right atrium (RA), right ventricle (RV), pulmonary artery (PA), and pulmonary capillary wedge pressure (PCWP).

    • Adjust scale as you go , nice trace settle , measure end of expiration

    • Wedge pressure O2 sats >95%, PCWP clear V waveform

    • Pullback from PCWP through to RA - record each pressure wave form change

Calculation Methods:

Cardiac Output :

  • Fick’s Method: Measures oxygen consumption and differences in oxygen content.

    • Normal CO: 4.0-6.0 L/min.

    • 1. Oxygen Consumption

    • 2. Oxygen content of arterial blood

    • 3. Oxygen content of mixed venous blood

EXAMPLE:

Direct versus Indirect Fick’s method:

The direct Fick method is preferred, but requires direct measurement of O2 uptake, a technique that is not widely available.

The indirect Fick method, which uses estimated values of O2 uptake, is acceptable but lacks reliability

  • Thermodilution Method: Involves change in temperature measurement post-fluid bolus injection.

  • Uses Swans Ganz catheter

  • Preferred method for calculating CO

  • In patients with intracardiac shunts, thermodilution may be inaccurate because of early recirculation of the injectate.

Cardiac Index: CI) adjusts output to patients BSA :

Normal CI: 2.4-4.0 L/min/m2

A cardiac index below 2.0 L/min/m2 might indicate cardiogenic shock in an acute setting

Analysing Pulmonary Vascular Resistance (PVR) :

  • The resistance against blood flow from the pulmonary artery to the left atrium

  • PVR Formula: Used for diagnosing pulmonary arterial hypertension (PAH).

    • Normal value: 0.25–1.6 WU. Values >3 WU indicate PAH.

    • A PVR >3 WU is required for the diagnosis of Pulmonary arterial hypertension

    • Is highly sensitive to changes in both flow and filling pressure, and may not reflect changes in the pulmonary circulation at rest

EXAMPLE:

Breakdown:

Calculating shunts:

Shunt formula:

Qp:Qs 1 = normal

Qp:Qs >1-1.5 = mild

Qp:Qs >1.5-2 = moderate

Qp:Qs >2 = severe

  • Usually shunt is L>R due to pressures

  • Can be R>L which would give a value of <1

Common Complications of RHC:

  • Potential Risks:

    • Ventricular arrhythmias

    • Advanced AV block

    • Right ventricular perforation

    • Pulmonary rupture or infarction

    • Pneumothorax

References

  • European Society of Cardiology guidelines and related literature on pulmonary hypertension and RHC practices.