Method and apparatus for treating hemodynamic disfunction

A method of effecting simultaneous contraction of both left and right ventricles of a heart for improving hemodynamic efficiency comprising the steps of:

• sensing the cardiac signals of the atria and separately sensing the cardiac depolarization signals of both the left and right ventricles;
• determining whether said cardiac depolarization signals are simultaneously present in both the left and right ventricles;
• stimulating at least one ventricle simultaneously with the contraction of at least one other ventricle after a predetermined A-V period in the event that said cardiac depolarization signals are determined not to be simultaneously present in both ventricles.

An atrial-coupled, bi-ventricular pacemaker for implantation or external use comprising atrial and ventricular sensing means for detecting cardiac signals, said sensing means including first and second ventricular electrodes connected in series for sensing and stimulating the right and left ventricles, respectively, and an atrial electrode adapted to be disposed in an atrial chamber for detecting cardiac signals of the atria, all of said electrodes being connected to separate ECG amplifier means for amplifying the sensed signals;

• a control circuit coupled to said ECG amplifier means for analyzing the cardiac signals picked up by said sensing means and providing a control signal;
• and a stimulating circuit means for producing an electrical stimulating pulse to the left ventricle in the absence of a detected cardiac signal from the left ventricle, and to the right ventricle in the absence of a detected cardiac signal from the right ventricle, and to both ventricles in the absence of detected cardiac signals from both ventricles to effect substantially simultaneous contraction of both ventricles after a predetermined A-V delay period.

A method for improving the hemodynamic efficiency of a heart comprising the steps of:

• detecting a cardiac depolarization signal originating from a first ventricle;
• immediately and unconditionally stimulating both ventricles for effecting a coordinated contraction of both ventricles when a cardiac depolarization signal originating from the first ventricle is detected.

A method for improving the hemodynamic efficiency of a heart comprising the steps of:

• sensing a contraction of the atria;
• and
• stimulating both ventricles for effecting a coordinated contraction of both ventricles when a contraction of the atria is sensed and following a predetermined A-V delay period.

A bi-ventricular pacemaker, comprising:

• sense means for sensing ventricular depolarization signals originating from one of left and right ventricles;
• and
• pulse generator means operative upon sensing a depolarization signal from the one of the ventricles for producing a stimulating pulse and immediately and unconditionally applying the stimulating pulse to both ventricles.

A bi-ventricular pacemaker comprising:

• detecting means for detecting a cardiac signal resulting from a contraction of a first ventricle;
• stimulating means for effecting immediate and unconditional contraction of a second ventricle in response to the detected cardiac signal, thereby effecting simultaneous contraction of both ventricles.