Apparatus and method for detecting abnormal cardiac rhythms in dual chamber arrhythmia control system

A dual chamber antitachycardia pacing device for the reversion of tachycardias in a patient's heart, comprising:

• means for generating atrial and ventricular stimulation pulses,
• means for determining the patient's intrinsic atrial heartbeat rate,
• at least one means for determining the patient's metabolic indicator rate,
• means for determining the patient's maximum atrial tracking rate as a function of said metabolic indicator rate,
• means for comparing said intrinsic atrial heartbeat rate to said maximum atrial tracking rate, and
• means responsive to said comparing means for controlling said generating means to operate in a first mode in which ventricular pacing pulses are generated in synchrony with said intrinsic atrial heartbeat rate when said intrinsic atrial heartbeat rate is slower than said maximum atrial tracking rate, and for controlling said generating means to operate in a second, antitachycardia pacing, mode when said intrinsic atrial heartbeat rate exceeds said maximum atrial tracking rate,
• wherein in said second mode, atrial and ventricular pacing pulses are generated and delivered in a series of pulse trains with each train consisting of a plurality of pacing pulses delivered in an alternating pulse sequence to the ventricle and to the atrium.

A dual chamber antitachycardia pacing device for the reversion of tachycardias in a patient's heart, comprising:

• means for generating atrial and ventricular stimulation pulses,
• means for determining the patient's intrinsic atrial heartbeat rate,
• at least one means for determining the patient's metabolic indicator rate,
• means for comparing said metabolic indicator rate with said intrinsic atrial heartbeat rate and, depending on the results of the comparison, classifying said intrinsic atrial heartbeat rate as either physiological or pathological;
• and
• control means operative when the atrial heartbeat rate is physiological for controlling said stimulation pulse generating means to operate in response to said intrinsic atrial heartbeat rate, and operative when the atrial heartbeat rate is pathological for controlling said stimulation pulse generating means to operate in an antitachycardia pacing mode.

A dual chamber antitachycardia pacing device for the reversion of tachycardias in a patient's heart, comprising:

• means for generating atrial and ventricular stimulation pulses,
• means for determining the patient's intrinsic atrial heartbeat rate,
• at least one means for determining the patient's metabolic indicator rate,
• means for comparing said metabolic indicator rate with said intrinsic atrial heartbeat rate and, depending on the result of the comparison, classifying said intrinsic atrial heartbeat rate as either physiological or pathological;
• and
• control means operative when the atrial heartbeat rate is physiological for controlling said stimulation pulse generating means to operate in response to said intrinsic atrial heartbeat rate, and operative when the atrial heartbeat rate is pathological for controlling said stimulation pulse generating means to operate in an antitachycardia pacing mode,
• wherein in said antitachycardia pacing mode, atrial and ventricular pacing pulses are generated and delivered in a series of pulse trains with each train consisting of a plurality of pacing pulses delivered in an alternating pulse sequence to the ventricle and to the atrium.

A dual chamber antitachycardia pacing device for the reversion of tachycardias in a patient's heart, comprising:

• means for generating atrial and ventricular pacing pulses;
• means for sensing atrial and ventricular heartbeats;
• at least one means for determining a metabolic indicator rate;
• means for ascertaining whether sensed atrial heartbeats are occurring at a rate which is pathological for said metabolic indicator rate;
• and
• means for controlling said generating and sensing means to operate normally in a DDDR mode but to switch to an antitachycardia pacing mode when the rate of the atrial heartbeats is pathological.

A dual chamber antitachycardia pacing device for the reversion of tachycardias in a patient's heart, comprising:

• means for generating atrial and ventricular pacing pulses;
• means for sensing atrial and ventricular heartbeats;
• at least one means for determining a metabolic indicator rate;
• means for ascertaining whether sensed atrial heartbeats are occurring at a rate which is pathological for said metabolic indicator rate;
• and
• means for controlling said generating and sensing means to operate normally in a DDDR mode but to switch to an antitachycardia pacing mode when the rate of the atrial heartbeats is pathological,
• wherein in said antitachycardia pacing mode, atrial and ventricular pacing pulses are generated and delivered in a series of pulse trains with each train consisting of a plurality of pacing pulses delivered in an alternating pulse sequence to the ventricle and to the atrium.

A method of utilizing a dual chamber antitachycardia pacing device to revert tachycardias in a patient's heart, comprising the steps of:

• determining the patient's intrinsic atrial heartbeat rate,
• determining the patient's metabolic indicator rate,
• determining a maximum atrial tracking rate as a function of said metabolic indicator rate,
• comparing said intrinsic atrial heartbeat rate to said maximum atrial tracking rate, and
• in response to said comparing step, generating ventricular pacing pulses in synchrony with said atrial heartbeat rate when said intrinsic atrial heartbeat rate is slower than said maximum atrial tracking rate and generating pacing pulses in an antitachycardia therapy mode when said intrinsic atrial heartbeat rate exceeds said maximum atrial tracking rate.

A method of utilizing a dual chamber antitachycardia pacing device to revert tachycardias in a patient's heart, comprising the steps of:

• determining the patient's intrinsic atrial heartbeat rate,
• determining the patient's metabolic indicator rate,
• determining a maximum atrial tracking rate as a function of said metabolic indicator rate,
• comparing said intrinsic atrial heartbeat rate to said maximum atrial tracking rate, and
• in response to said comparing step, generating ventricular pacing pulses in synchrony with said atrial heartbeat rate when said intrinsic atrial heartbeat rate is slower than said maximum atrial tracking rate and generating pacing pulses in an antitachycardia therapy mode when said intrinsic atrial heartbeat rate exceeds said maximum atrial tracking rate,
• wherein said antitachycardia therapy mode includes the sub-steps of:
• delivering a pulse to the ventricle,
• determining a V-A delay interval as a function of said metabolic indicator rate,
• delivering a pulse to the atrium at the expiration of said determined V-A interval in the absence of an intrinsic atrial heartbeat during said V-A interval,
• determining an A-V delay interval as a function of said metabolic indicator rate,
• delivering a pulse to the ventricle at the expiration of said A-V interval in the absence of an intrinsic ventricular heartbeat during said A-V interval,
• repeating the aforesaid pulse deliveries to the atrium and the ventricle for a plurality of intervals defining a pulse train, and
• varying said A-V delay interval value from the initial value at least once prior to the completion of a series of trains of pulses.

A method of utilizing a dual chamber antitachycardia pacing device to revert tachycardias in a patient's heart, comprising the steps of

• generating atrial and ventricular pacing pulses;
• sensing the patient's atrial and ventricular heartbeats and determining the patient's atrial and ventricular heartbeat rates;
• determining the patient's metabolic indicator rate;
• ascertaining whether sensed atrial heartbeats are occurring at a rate which is pathological for said metabolic indicator rate;
• and
• performing said generating and sensing steps in a DDDR mode when said atrial heartbeat rate is non-pathological, and in an antitachycardia pacing mode when said atrial heartbeat rate is pathological.

A method of utilizing a dual chamber antitachycardia pacing device to revert tachycardias in a patient's heart, comprising the steps of:

• generating atrial and ventricular pacing pulses;
• sensing the patient's atrial and ventricular heartbeats and determining the patient's atrial and ventricular heartbeat rates;
• determining the patient's metabolic indicator rate;
• ascertaining whether sensed atrial heartbeats are occurring at a rate which is pathological for said metabolic indicator ate;
• and
• performing said generating and sensing steps in a DDDR mode when said atrial heartbeat rate is non-pathological, and in an antitachycardia pacing mode when said atrial heartbeat rate is pathological,
• wherein said antitachycardia therapy mode includes the substeps of:
• delivering a pulse to the ventricle,
• determining a V-A delay interval as a function of said metabolic indicator rate,
• delivering a pulse to the atrium at the expiration of said determined V-A interval in the absence of an intrinsic atrial heartbeat during said V-A interval,
• determining an A-V delay interval as a function of said metabolic indicator rate,
• delivering a pulse to the ventricle at the expiration of said A-V interval in the absence of an intrinsic ventricular heartbeat during said A-V interval,
• repeating the aforesaid pulse deliveries to the atrium and the ventricle for a plurality of intervals defining a pulse train, and
• varying said A-V delay interval value from the initial value at least once prior to the completion of a series of trains of pulses.