Heart failure (HF) patients receive similar benefits from implantable devices fitted with telemonitoring technology alerting medical experts to problems regardless of whether they are fitted with cardioverter defibrillators (ICD) or cardiac resynchronization therapy defibrillators (CRT-D), reported the latest analysis of the IN-TIME trial in yesterday’s Late Breaking Trial session. “Prior to this investigation we were unclear whether the overall benefits found in the IN-TIME study applied to both the ICD and CRT-D populations. Our study clearly shows that telemonitoring technology is worthwhile for both groups,” said Gerhard Hindricks, the lead investigator and presenter of the INTIME trial.
Increasingly HF patients are implanted with ICD or CRT-D devices with telemonitoring functions enabling data to be submitted directly to monitoring centres. Transmittable parameters include mean heart rate, ventricular extra systoles per hour, heart rate variability, AF burden, and the occurrence of atrial or ventricular tachyarrhythmias. Technical data can also be transmitted on battery status, or lead connections. The technology involves implants having small antennae that export data to a transmission unit, located close to the patient’s bed at a set time each night (e.g. at 3 am). From the home monitoring platform data are then transmitted by mobile phone to a service centre where the data are processed, and specific messages generated for physicians responsible for monitoring individual patients in the form of SMS, emails or phone calls. “The idea is that rapid transmission of information compared to traditional methods of monitoring patients gives physicians more time to intervene if necessary thereby preventing serious or even fatal events,” explained Hindricks, from the Heart Centre Leipzig, Germany. Taking the example of HF patients who develop sudden onset atrial fibrillation (AF), he said, it would be possible to prescribe anticoagulation treatments and prevent stroke.
The IN-TIME study was designed to assess the impact of home monitoring on the clinical status of HF. For the study, 664 patients with chronic HF lasting for three months or more, and a reduced left ventricular ejection fraction of <35% who had been fitted with implanted devices that had a telemonitoring function were randomized 1:1 to either telemonitoring (n=333) or standard care (n=331). Overall 58.1% (n=390) of patients received the CRT-D device and 41.9% (n=274) the ICD device. The primary endpoint of the trial was the modified Packer score, a clinical composite consisting of mortality, overnight hospitalization for worsened HF and NYHA class global self assessment, and the secondary endpoint was all cause total mortality.
Results, presented at the 2013 ESC Annual meeting in Amsterdam, showed that at 12 months follow up 27.5% of patients in the control group experienced worsening according to the modified Packer score versus 18.9% in home monitoring group (p<0.05). Furthermore, results showed home monitoring reduced one-year mortality from 8.7% for those who had no telemonitoring to 3.4 % for those who had telemonitoring (P=0.0004). In the current analysis the investigators have analysed the benefits separately for the ICD and CRT-D patient populations.
Results of the latest analysis show that at baseline ICD patients had significantly lower mean age (63.5 years versus 67.0 years), higher prevalence of ischemic heart disease (80% versus 61%), more NYHA class II symptoms (67% versus 26%), and higher ejection fractions (27% versus 26%) than CRT-D patients (P<0.001 for all parameters). Results at one year showed the primary outcome occurred in 26.4% of CRT-D patients versus 18.2% of ICD patients (P=0.014). However, the relative risk reduction of patients in the telemonitoring group experiencing the primary outcome versus the control group was similar for both ICD (RR 0.61; P=0.06) and CRT-D (RR 0.75; P=0.10) patients.
“We were unsurprised that CRT-D patients experienced more primary outcomes than ICD patients since they are generally a sicker population with more advanced HF. In both groups we showed patients who had telemonitoring did significantly better than those did not,” said Hindricks.
Further analyses, he added, are now planned to look at the control group (whose data was transmitted to the centre but not passed on to clinicians) to explore predictors of death and other events. “With the undoubted efficacy of telemonitoring organisations like the ESC, HFA and European Heart Rhythm Association (EHRA) now need to lobby politicians, departments of health and insurance companies to persuade them that the initial financial outlay for the technology will ultimately prove cost effective,” said Hindricks.