Study population and Data Available
During the COVID-19 pandemic, Italian hospitals have been forced to
adapt and to restructure their organization to cope with this urgent new
critical situation.
As patients’ office visits were discouraged and many outpatient clinics
were temporarily closed, alternative solutions, such as remote telematic
health visits and telemonitoring (RM) have been adopted or implemented
in order to focus on selected “high risk” patients in need of closer
surveillance, as recommended by HRS Expert Consensus Statement and, more
specifically, by Italian Arrhythmology and Cardiac Stimulation Society
(AIAC). 5,6
RM provides the automated transmission of data based on prespecified
alerts related to device function and clinical events. This allows rapid
detection of abnormal device function and/or arrhythmia events. RM of
these devices allows the transfer of the information stored
in the
implantable device so that it can
be accessed by the clinic personnel via a secured website.
By this tool, we analysed a large cohort of remotely monitored ICD and
CRT-D recipients, who had undergone device implantation before January
1st, 2019 at 7 Hospitals of Campania Region, comparing
the arrhythmias incidence of the lockdown to the arrhythmias rate of the
corresponding period in 2019. In total, 574 patients were initially
selected in a retrospective fashion for this multicentre and
observational study. All patients enrolled had been implanted according
to European Society of Cardiology/European Heart Rhythm Association
guidelines criteria for ICD/CRT-D implant, had received remote
monitoring devices after signing a specific written informed consent for
the utilization of their device data. Among all subjects under AICD and
CRT-D remote monitoring at our hospitals, we selected 574 patients who
had undergone AICD or CRT-D implant before 2019 and at least one office
visit in the last 2 years and during the global observation period. None
of the included patients was hospitalized due to COVID-19 infection or
to acute respiratory distress.
Diagnosis of Arrhythmias
and Device Programming
The devices of all patients selected for this study are equipped with
reliable diagnostic algorithms that provide a series of alerts related
to technical issues and to the occurrence of arrhythmic events. We
focused on relevant cardiac arrhythmias including AF, ventricular
tachycardia (VT) and ventricular fibrillation (VF). The diagnosis was
initially made by the device via automatic detection and discrimination
of episodes (AF/VT/VF); at second instance diagnosis was confirmed by an
experienced physician via remote analysis of endocavitary strip received
for each patient once or twice a week from January 2019 to May 2020,
according to remote monitoring rules of each hospital involved in the
research. Specifically, for all patients, we reviewed telemetry logs and
confirmed the diagnosis of arrhythmias detected by device. Among all
arrhythmias recorded by device, the ones analysed included incident VT,
VF and new-onset AF. Out of these, we examined exclusively the ones that
required device intervention: switch mode in the case of AF, life-saving
therapy as anti-tachycardia pacing (ATP) and/or shock therapy in other
cases. For AF count, in addition to device intervention, episodes with a
duration of at least six hours and a cardiac rate above 220 beats per
minute threshold were considered.
Subjects with permanent AF were excluded from the AF analysis.
Patients were excluded from the analysis if during follow-up they
experienced hospital admission for: VT or AF ablation procedure,
trans-catheter aortic valve implantation, mitral clip implantation.
At implant and at in-office evaluations (pre-lockdown) specific
recommendations for device programming according to patient profile had
been adopted, thus minimizing troubleshooting during follow
up7. In particular, both standardized and conventional
and tailored device programming was adopted to guarantee efficacy and
safety of the therapy. All patients implanted for primary prevention
have shown as first therapy three attempts of ATP for VT zone (from 180
to 200-220 bpm) and a sequence of ATP during capacitor charging for VF
zone (>200-220 bmp); long detection time (intervals or
cycles) in any window (setting depends on manufacturer’s device); shocks
always delivered at the maximum energy (at least 30 J) in VT and VF
zone; and the use of discrimination criteria for VT zone up to 200-220
bpm. Among patients implanted for secondary intervention, the 65% of
cases has received a specific “MADIT-RIT” programming: therapies only
for high heart rates (> 200 bpm, VF
zone).8,9 In these patients a “tailored” programming
approach was adopted through the knowledge of arrhythmic history, ECG
morphology, cycle length and patients’ tolerance, in order to cover all
clinical arrhythmias efficiently. No Monitor zone were found in all the
devices examined.