A medical system for providing a defibrillation therapy to a patient, the system comprising: a cardiac monitoring device (CMD 102) configured to sense and record physiological data indicative of the patient's cardiac function and to perform arrhythmia detection, the CMD including CMD control circuitry, CMD data storage circuitry, at least one CMD sensing electrode operatively coupled to the control circuitry, a CMD communication component, and a CMD power source coupled to the control circuitry and the CMD communication component; and a wearable cardiac defibrillator (WCD 106) configured to deliver the defibrillation therapy, the WCD configured to be positioned external to and supported by the patient and including: a WCD communication component, WCD control/storage circuitry, a WCD power supply, a defibrillator, at least one therapy electrode, and at least one WCD sensing electrode; wherein the CMD communication component and the WCD communication component are configured to operatively couple the CMD and the WCD to one another, the WCD is configured to: detect an arrhythmia and, in response to detecting the arrhythmia, transmit a query including patient data obtained from the at least one WCD sensing electrode to the CMD about whether the arrhythmia detected by the WCD is treatable by the WCD; and the CMD is configured to: determine, using the patient data transmitted by the WCD as well as patient information obtained from the at least one CMD sensing electrode, whether the arrhythmia detected by the WCD is treatable by the WCD and, in response to determining that the arrhythmia detected by the WCD is treatable by the WCD, transmit a confirmation signal to the WCD that permits the WCD to deliver a therapeutic shock, and in response to determining that the arrhythmia detected by the WCD is not treatable by the WCD, transmit an abort signal to the WCD that commands the WCD to abort therapy delivery. a cardiac monitoring device (CMD 102) configured to sense and record physiological data indicative of the patient's cardiac function and to perform arrhythmia detection, the CMD including CMD control circuitry, CMD data storage circuitry, at least one CMD sensing electrode operatively coupled to the control circuitry, a CMD communication component, and a CMD power source coupled to the control circuitry and the CMD communication component; and a wearable cardiac defibrillator (WCD 106) configured to deliver the defibrillation therapy, the WCD configured to be positioned external to and supported by the patient and including: a WCD communication component, WCD control/storage circuitry, a WCD power supply, a defibrillator, at least one therapy electrode, and at least one WCD sensing electrode; wherein the CMD communication component and the WCD communication component are configured to operatively couple the CMD and the WCD to one another, the WCD is configured to: detect an arrhythmia and, in response to detecting the arrhythmia, transmit a query including patient data obtained from the at least one WCD sensing electrode to the CMD about whether the arrhythmia detected by the WCD is treatable by the WCD; and the CMD is configured to: determine, using the patient data transmitted by the WCD as well as patient information obtained from the at least one CMD sensing electrode, whether the arrhythmia detected by the WCD is treatable by the WCD and, in response to determining that the arrhythmia detected by the WCD is treatable by the WCD, transmit a confirmation signal to the WCD that permits the WCD to deliver a therapeutic shock, and in response to determining that the arrhythmia detected by the WCD is not treatable by the WCD, transmit an abort signal to the WCD that commands the WCD to abort therapy delivery.