Percutaneous Temporary Placement of a Phrenic Nerve Stimulator for Diaphragm Pacing, a First in Human Trial

Inclusion Criteria: * Able and willing to give informed consent or whose legally authorized representative is able and willing to give informed consent. * Able to undergo general anaesthesia (sedation, intubation and mechanical ventilation) * Susceptible indication for atrial septal defect closure Exclusion Criteria: * Subject has an EF of \< 30% * Subject has a co-morbid illness or life expectancy \< 2 years * Subject has experienced an AMI within 72 hours prior to this procedure * Subject is contraindicated for or unwilling to take aspirin or anticoagulants * Subject is in cardiogenic shock * Subject has other cardiovascular disease requiring open heart surgery * Subject is known to have a demonstrated intra cardiac thrombus on echocardiography * Subject has been treated with paralytic medications within 72 hours prior to procedure * Subject has significant thoracic abnormalities such that placement of a left subclavian line would be difficult * Inability to cannulate the left subclavian vein (post-consent exclusion) * Subject has a known or suspected phrenic nerve paralysis * Subject has co-existing temporary or implanted cardiac electrical devices such as a pacemaker or defibrillator * Subject has an active systemic infection or local infection at or around the insertion site * Subject is known or suspected to be pregnant or is lactating * Subject will be unavailable for, or is unwilling to comply with, follow up requirements of the protocol * Subject is currently enrolled in any other study of an investigational drug or device who has received treatment under that protocol with the investigational product during the 30 days prior to screening.