Dynamic RF Power and Irrigation Control for Cardiac Ablation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Legacy ablation systems face challenges in efficiently delivering ablative power to myocardial tissue, leading to incomplete inactivation or irreversible trauma, and require longer-than-optimal ablation times due to fixed irrigation rates that can cause tissue overcooling or steam-pops.
Innovation Solution
A medical apparatus with a probe and electrode for radiofrequency ablation, incorporating a temperature sensor and a pump for controlled irrigation, where the processor adjusts RF power and irrigation rates dynamically to maintain a preset target temperature, pulsing between low and high irrigation rates to optimize energy delivery and prevent tissue damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If fixed irrigation rates are used during ablation, then tissue cooling is maintained, but ablation time increases and tissue damage occurs
Solution Approach 1:
The irrigation flow rate is dynamically adjusted during ablation based on real-time temperature feedback. The system transitions from fixed irrigation rates to variable rates, increasing flow when temperature exceeds thresholds and decreasing flow when temperature is adequate, thereby optimizing both tissue temperature control and ablation efficiency
Solution Approach 2:
A temperature sensor provides real-time feedback on tissue temperature during ablation. This feedback is used by the control system to iteratively adjust both RF power delivery and irrigation flow rate, creating a closed-loop control system that maintains temperature within target ranges while minimizing ablation time
2Productivity
If high RF power is applied to accelerate ablation, then productivity increases, but tissue trauma and steam-pops occur
Solution Approach 1:
Real-time temperature monitoring provides feedback that prevents excessive RF power application. When temperature approaches harmful thresholds, the system automatically reduces power delivery, preventing tissue trauma and steam-pops while maintaining efficient ablation progress
Solution Approach 2:
The system proactively prevents tissue trauma by monitoring temperature trends and preemptively adjusting RF power and irrigation rates before harmful conditions develop. This preliminary anti-action avoids the need for corrective measures after damage occurs
3Productivity
If low irrigation rates are used to maintain ablation efficiency, then productivity improves, but tissue temperature becomes uncontrolled
Solution Approach 1:
The irrigation system dynamically adjusts flow rates based on real-time temperature conditions. Rather than using consistently low rates, the system increases irrigation when temperature rises and maintains low rates when temperature is optimal, achieving both efficiency and control
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enables efficient and controlled ablative power delivery, minimizing trauma risk and reducing ablation time by dynamically adjusting RF power and irrigation rates, ensuring consistent tissue temperature and preventing issues like tissue charring or steam-pops.
Implementation Method 1
A temperature sensor (e.g., a thermistor) is incorporated in the probe
Implementation Method 2
A radiofrequency (RF) signal generator is configured to apply RF power via the electrode to the myocardium, so as to ablate the myocardium
Implementation Method 3
pump configured to irrigate the myocardium, via the probe, with an irrigation fluid at a controllable rate
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Apparatus, consisting of a probe configured to be inserted into contact with a myocardium, and an electrode attached to the probe. A temperature sensor, incorporated in the probe, is configured to output a temperature signal. A pump irrigates the myocardium, via the probe, with an irrigation fluid at a controllable rate, and a radiofrequency (RF) signal generator applies RF power via the electrode to the myocardium, so as to ablate the myocardium. The apparatus also has processing circuitry that measures a temperature of the probe, based on the temperature signal, while the RF power is applied and, when the measured temperature exceeds a preset target temperature, iteratively reduces the RF power applied by the signal generator and concurrently iteratively varies a rate of irrigation of the irrigation fluid provided by the pump, until the measured temperature is reduced to the preset target temperature.