Tetralogy of Fallot Index Score for Mortality Risk Prediction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for assessing the severity of Tetralogy of Fallot (ToF) in children are limited by high false-negative and false-positive error rates, inability to accurately predict mortality risk, reliance on invasive procedures, and lack of a quantitative scoring system for prioritizing surgical resources, leading to under-prediction of mortality risk and unfair allocation of surgical capacity.
Innovation Solution
A method using serial measurements of Brain Natriuretic Peptide (BNP) levels in plasma to calculate a Tetralogy of Fallot Index (TOFI) score, which is log-transformed and z-scored, and applied to a Cox Proportional Hazards model for predicting mortality risk and prioritizing surgical interventions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If current methods for assessing ToF severity are used, then surgical resource allocation can be performed, but high false-negative and false-positive error rates result in inaccurate mortality risk prediction
Solution Approach 1:
The patent transforms the assessment from qualitative clinical evaluation to quantitative measurement by using BNP levels as a measurable parameter. Serial BNP measurements are converted into a velocity metric (rate of change over time), which serves as a precise quantitative indicator of mortality risk, thereby improving both measurement precision and reliability
Solution Approach 2:
The patent replaces invasive mechanical assessment procedures with a biochemical measurement system. Instead of relying on invasive cardiac catheterization or complex imaging, the assessment is substituted with blood-based BNP measurement, which is less invasive yet provides more accurate and reliable mortality risk prediction
2Measurement precision
If invasive procedures are used for ToF assessment, then diagnostic accuracy can be improved, but patient morbidity and procedural complexity increase
Solution Approach 1:
The patent substitutes invasive mechanical procedures (cardiac catheterization, complex imaging) with a simple blood draw for BNP measurement. This biochemical assay provides equivalent or superior diagnostic accuracy without the risks, pain, and recovery time associated with invasive procedures
Solution Approach 2:
The patent employs a simple, disposable blood sample collection method instead of expensive, complex invasive equipment. The BNP assay uses routine laboratory technology that is widely available, making the diagnostic process accessible and eliminating the need for specialized invasive procedure equipment
3Reliability
If no quantitative scoring system is used, then surgical resource allocation can be performed based on clinical judgment, but unfair allocation and under-prediction of mortality risk occur
Solution Approach 1:
The patent replaces subjective clinical judgment with an objective computational algorithm. The TOFI score is calculated automatically from serial BNP measurements using a standardized formula, eliminating human bias and ensuring fair, consistent resource allocation decisions across all patients
Solution Approach 2:
The patent creates a simplified numerical representation (TOFI score) that copies the essential mortality risk information from complex clinical data. This single number captures the critical risk factors and enables straightforward comparison and prioritization without requiring clinicians to process complex multi-parameter data
Data Source
AI summary
Systems and methods are provided for monitoring mortality risk in children with congenital cyanotic heart condition such as Tetralogy of Fallot (ToF) including prioritizing ToF patients for medical treatment and determining that a ToF patient is eligible for urgent surgical correction. Some embodiments of the invention determine a prognosis in terms of a predicted survival probability within a timeframe wherein the pediatric subject awaits surgical correction, based on determining the amount of a marker, such as BNP (brain natriuretic peptide) in serial samples of blood plasma from the subject and determining a Tetralogy of Fallot Index (TOFI®) score from the biomarker values. Some embodiments of the invention use the score to determine severity of the heart condition for one or more patients, which may be used for managing treatment, such as scheduling surgery, transfers to available treatment centers, managing medical resources, or predicting costs, including for settings where the resources to perform pediatric cardiac surgery are limited.