Abstract: A novel double-balloon septal defect occlusion catheter which is used in conjunction with a unique surgical procedure to temporarily close septal perforations, particularly spontaneous ventricular septal perforations following acute myocardial infarction, without the need for open heart surgery, thus permitting the patient's condition to stabilize and permitting elective surgical closure of the defect at a later date.

Abstract: Self-contained, micro-electronic heart monitor for mounting on or near the heart during surgery, to monitor the electrical activity of the heart during cardioplegic arrest by picking up and amplifying electrical signals from the heart and displaying an output when the signal exceeds a threshold level.

Abstract: The circuit comprises an elapsed time indicating meter and a silicon-controlled rectifier, used to supply power to the meter, connected in series across the circuit's first and third terminals. Additionally, the circuit includes a small resistor connected between the second and third input terminals, that is, connected in series with the a.c. device. This small resistor receives the current through the a.c. device and the voltage across the small resistor is indicative of the operational state of the a.c. device. A variable potentiometer is connected full scale across the small resistor and the variable voltage is amplified by a common-base transistor. This amplified voltage is both rectified and filtered, serving as the SCR's gate terminal input for triggering the SCR.The potentiometer is adjustable to allow the SCR to trigger in either one of two conditions.