Atrial Pacing Sequence Control After Premature Atrial Contractions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current pacing schemes for preventing atrial fibrillation following premature atrial contractions are ineffective, as they may lead to unnecessary high-frequency pacing, fail to timely escape atrial cells from the steep region of electrical recovery characteristics, and create conditions for atrial fibrillation through fixed frequency overdrive pacing or 'short-long-short' sequences.
Innovation Solution
A pacing device that utilizes an atrial sensing module, pacing module, clock/timing module, data statistics module, and storage module to calculate and adjust pacing intervals based on atrial intervals and safe pacing intervals, constructing smooth transition pacing sequences to prevent atrial fibrillation by avoiding steep regions and 'short-long-short' sequences.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If fixed frequency overdrive pacing is used after premature atrial contraction, then the pacing rhythm is simplified and easy to implement, but it may lead to 'short-long-short' sequences and fail to escape atrial cells from steep region of electrical recovery characteristics, promoting atrial fibrillation
Solution Approach 1:
The patent implements dynamic pacing interval adjustment by transitioning from fixed frequency overdrive pacing to a multi-phase pacing strategy with gradually lengthening intervals. The pacing interval is dynamically modified based on the phase of electrical recovery, escaping the steep region by progressive interval extension rather than maintaining a fixed pace.
Solution Approach 2:
The patent changes the pacing interval parameter progressively through defined phases: initial overdrive pacing phase with shorter intervals to escape the steep region, followed by a transition phase with gradually lengthening intervals, and finally a maintenance phase with stable longer intervals. This parameter evolution prevents atrial fibrillation while avoiding 'short-long-short' sequences.
2Adaptability or versatility
If pacing interval is gradually lengthened in proportion after premature atrial contraction, then the pacing adapts to heart rate changes, but the diastolic interval may remain in the steep region of electrical recovery characteristics curve, failing to prevent atrial fibrillation
Solution Approach 1:
The patent applies preliminary overdrive pacing at a controlled rate before allowing gradual heart rate adaptation. This initial phase forces the atrial cells through the steep region of electrical recovery characteristics under controlled conditions, preventing subsequent arrhythmias while the heart rate subsequently adapts to physiological needs.
Solution Approach 2:
The patent employs periodic pacing with specifically designed interval patterns that include an initial phase of more frequent pacing to escape the vulnerable period, followed by progressive interval lengthening. This periodic structure ensures reliable prevention while allowing eventual heart rate adaptation.
3Reliability
If high-frequency pacing is applied after premature atrial contraction to prevent atrial fibrillation, then the prevention effect is enhanced, but unnecessary energy consumption increases and device burden rises
Solution Approach 1:
The patent applies overdrive pacing selectively during the critical period following premature atrial contraction when atrial fibrillation risk is highest, rather than maintaining continuous high-frequency pacing. This partial application of excessive pacing provides sufficient prevention effect while limiting energy consumption to the necessary minimum.
Solution Approach 2:
The pacing frequency is dynamically adjusted to match the physiological need for prevention: higher frequency during the vulnerable post-PAC period, then progressively reducing to normal rates. This dynamic adjustment optimizes the balance between prevention effectiveness and energy conservation.
4Device complexity
If pacing stimulation is delivered without modification after premature atrial contraction, then the device operation is simple, but it causes stimulation to fall into steep region of electrical recovery characteristics or form 'short-long-short' sequence, promoting atrial fibrillation
Solution Approach 1:
The device detects premature atrial contractions and preemptively modifies the pacing interval before the next scheduled stimulus. This preliminary detection and response prevents the harmful 'short-long-short' sequence and ensures stimulation does not fall into the steep region of electrical recovery characteristics.
Solution Approach 2:
The device uses feedback from intracardiac electrogram detection to identify premature atrial contractions and automatically adjusts subsequent pacing intervals. This closed-loop feedback mechanism prevents atrial fibrillation without requiring complex external control, maintaining device simplicity while improving reliability.
Data Source
AI summary
Disclosed in the present invention is a pacing device for preventing occurrence of atrial fibrillation following premature atrial contraction, including: adjusting values of the number M of atrial events and the number N of premature atrial contraction events to control a pacing control process for preventing the occurrence of atrial fibrillation following premature atrial contraction to take place after a single or more than one premature atrial contraction events, and on the basis of a current p-p′ interval, an atrial safe pacing interval and an average atrial interval, setting a smooth transition pacing sequence. The smooth transition pacing sequence avoids atrial compensation intervals caused by the premature atrial contraction and avoids occurrence of a “short-long-short” sequence. Meanwhile, the number of pacing intervals in the smooth transition pacing sequence is controllably set, and the pacing intervals included sequentially increase and are gradually in transition to the average atrial interval representing a normal atrial interval prior to the occurrence of the premature atrial contraction events, so that the occurrence of the alternation of action potential durations is avoided, and the occurrence of atrial fibrillation caused by the premature atrial contraction is prevented at multiple levels.