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Remote ICD Monitoring: Discussing the Technology with Dr. Lawrence Gessman
May 2005
When did you start utilizing remote ICD technology?
I started using remote ICD technology approximately 10 years ago. I invented a method of telemetering the beeps emanating from the original ICDs simultaneous with patient ECGs over the telephone. This so-called "beepergram" method of ICD follow-up was excellent for detecting T wave oversensing and double counting of QRS complexes, which were common problems causing false positive shocks in early defibrillators. In addition, atrial arrhythmias causing false positive shocks were also commonly found. Raytel Medical Corporation, under the leadership of Mr. Al Zinberg, funded a study of transtelephonic ICD follow-up using this beepergram methodology. One hundred beepergram patient units were manufactured, in addition to one receiving station located at Raytel in Connecticut. A total of 100 patients were monitored for approximately one year. The clinical usefulness yield of detecting abnormalities and patient ease of use were documented, but never published. The data was used to develop a justification for a billing code for transtelephonic ICD follow-up. The technology was immediately made obsolete when ICDs were combined with pacemakers and sophisticated programming and telemetry of ICD devices became available, and beeps produced by magnets no longer were used to check ICD sensing.
I then served as a consultant to St. Jude Medical Corporation to help them develop the "housecall" transtelephonic ICD monitoring system, which is currently in use today. Over the past three years, I have enrolled a number of patients in Raytel s Housecall Service, and find it extremely useful.
Describe the services that Raytel Medical Corporation's remote ICD monitoring provides. What type of information can be obtained from remote ICD monitoring?
The Raytel Housecall Plus monitoring system is similar to a programmer interrogating all modern St. Jude Medical ICDs. The interrogation report generated by Raytel s ICD monitoring service is identical to the report generated by the program after an office interrogation of the device. All device parameter settings, battery status, lead status and arrhythmia histograms, data, and real-time and stored electrograms are captured and reported by Housecall. The only feature available in the office not available on Housecall Plus is the ability to perform pacing capture thresholds.
How long are patients monitored for? How often do their physicians receive reports on the condition of the patient?
The Housecall Plus patient transmitter looks like a small programmer with two wristband ECG electrodes for ECG captures and a wand the patient holds over the device for interrogation. The transmitter connects to the patient s telephone line via the standard connector. Raytel s technicians can prompt the patient when to pick up the telephone and talk when necessary. A typical interrogation session takes approximately 10 minutes. I typically routinely monitor my patients every three months. Patients are told to make additional calls for symptoms such as palpitations or shocks. Raytel faxes and/or mails the results of routine, normal reports to my office. If you choose, Raytel can also email reports or make them available via a secure website. Raytel personnel will call me stat if serious abnormalities or serious arrhythmias are detected, and the security of knowing I will always be alerted to these events is reassuring to me and my patients.
If, for example, a patient is shocked at home, briefly describe the next steps taken by the remote monitoring service.
I instruct my patients to call Raytel immediately and transmit a Housecall interrogation if they receive one shock and feel well after the shock. If they receive two or more shocks, have chest pain, shortness of breath, or nausea after the shock, they are instructed to instead go immediately to the Emergency Room. Raytel will page me, fax the Housecall interrogation to me, and provide me with the patient s home telephone number. I call the patient back immediately after reviewing the electrogram and shock data. In most cases, the shock is appropriate for VT and the patient is allowed to stay at home. In some cases, the shocks are caused by atrial arrhythmias, requiring an office visit immediately or in the very near future to reprogram the device to avoid shocking SVT and start therapy for SVT. In rare cases, the shock is a phantom shock and the patient is reassured. Most "emergency shock calls" take 10-15 minutes to resolve. The encounter is convenient for both the patient and physician usually avoiding emergency room visits for both.
Tell us about one of your cases in which having "real time" remote ICD monitoring was crucial.
I have a dramatic case demonstrating the usefulness of transtelephonic ICD monitoring. One of my patients spends three months during the winter in Florida. He was suddenly observed to faint, followed by what appeared to witnesses to be grand mal seizures, and was admitted to a Florida hospital for a neurologic work-up. I arranged for a Housecall transmission be sent from the hospital to Raytel. The remote interrogation revealed an episode of VF, not converted by a low-energy shock, but successfully treated by the ICD on the second high-energy shock attempt. The patient s "seizure" was simultaneous in time with this event. The neurologic work-up was canceled, and the patient advised to see a local electrophysiologist to program a higher energy first shock for more rapid conversion of VF.
Describe the recently published study (from the Journal of Cardiac Electrophysiology 2004;11:161-166) from the Cleveland Clinic, which worked with Raytel Medical Corporation to demonstrate that ICD patients could be safely monitored from a remote location.
The recently published study from the Cleveland Clinic documented the usefulness and reliability of transtelephonic ICD monitoring. The study also documented ease of patient use, and patient acceptance of telephone visits substituting for personal visits with their EPS monitoring physician.
How will the recent SCD-HeFT Trial data, as well as the new ICD coverage provided by CMS, change who receives ICDs?
The recent SCD-HEFT trial data will certainly lead to an increase in implants of ICDs. The large reservoir of patients with nonischemic cardiomyopathies with an ejection fraction of less than 35% are now candidates for prophylactic ICD implantation. The larger increase in ICD implants will result in a large increase in ICD follow-up visits. I believe routine follow-up of many of these patients by telephone, or alternating office with telephone visits, will allow electrophysiologists to expand their effectiveness and efficiency of routine ICD follow-up, without sacrificing any quality of follow-up. I believe emergency follow-up is always enhanced when a patient is on transtelephonic monitoring because of the speed of determining what caused the outpatient shock or palpitations as described in answers 4 and 5 above.
What types of patients benefit the most from the remote ICD technology? In addition, from how far a distance can the patient still be safely monitored?
Patients located far from their electrophysiologist s office are most benefited by transtelephonic follow-up. Both routine "visits" and emergency "post-shock visits" are accomplished faster with no loss of accuracy, by telephone. In cases of true emergency, where the patient must go to the ER after an event, the data learned via Housecall transmission to the patient s remotely located electrophysiologist can be relayed, with suggestions on proposed therapy to the ER or local physicians caring for the patient. Telephone monitoring is practical from anywhere in the USA. Distance is not a factor. The only factor is use of the standard American telephone network to connect to and transmit Housecall information.
How does remote ICD monitoring compare with a patient's standard follow-up clinical or doctor visits? How often does a patient need to come in for doctor visits? Does this reduce the need for doctor visits?
Telephone monitoring can certainly substitute for some office visits. In my practice, I am aiming for alternating office and telephone visits every three months, resulting in two office visits per year and two routine telephone visits per year. My patients are encouraged to use Housecall liberally if they experience shocks or palpitations. The office visit still enables you to examine the patient and perform pacing threshold measurements. Everything else can be equally well done by telephone, with increased speed and convenience for both the patient and monitoring doctor. The Cleveland Clinic paper demonstrated that patient acceptance of telephone monitoring is high. They still feel equally well connected to their monitoring physician.
Is the remote monitoring available for both ICDs and pacemakers?
St. Jude Medical s Housecall Plus style remote monitoring is only available for St. Jude Medical s ICDs. This type of monitoring is actually the same as interrogation, with modern transfer of data. Medtronic, Inc., Biotronik, and Guidant Corporation have their own ICD monitoring methodologies, but also have not applied them to pacemaker follow-up yet. To the best of my knowledge, pacemaker monitoring is not yet available except by standard ECG FM real-time tone modulation methods.
We've described the many benefits of remote ICD monitoring to the ICD patient. What are some of the other benefits of remote ICD monitoring to the physicians?
The benefit of remote ICD monitoring is primarily to the physician. The speed and convenience and certainty of diagnosis of what caused the outpatient palpitation or shock is the most valuable aspect of remote monitoring. The ability to substitute some routine visits with telephone visits will also enable increasingly busy electrophysiologists to monitor an ever-increasing number of outpatients without loss of quality.
For more information, please visit Raytel Medical Corporation s website:
www.raytel.com