The novel coronavirus-2 (SARS-Cov-2) has spread from China all over the world, and the national health systems had to cope with primary and secondary effects of the SARS-Cov-2 disease (COVID-19). The world of neurology has not been immune to the virus either [1,2,3], and beyond its primary impact on the population, secondary consequences of the pandemic emerged for time-dependent diseases, including stroke. The extension of reperfusion window and the brought-on-stage of thrombectomy exponentially increased stroke care treatments until late 2019 [4]. Starting from the earliest stages of the emergency, the risk of underestimating and undertreating many cases of stroke that could have benefited from treatment was recognized and it generated an appeal not to stay at home if acute neurological symptoms appeared [5]. However, in the first period of the pandemic, we assisted to a 50% reduction in admissions to the emergency department (ED) or stroke units for acute ischemic stroke, according to data from 81 stroke units in Italy reported by the Italian Stroke Organization and similar rates were seen in France [6]. A 50% reduction in a number of thrombectomies has also been reported in Shanghai in the first month of the pandemic [7], pointing to a plausible consequence of the pandemic on stroke time-dependent pathway. In the 2-week timeframe that included the end of March and the beginning of April 2020, compared with the same period of the previous year, the analysis of total acute treatments for stroke in the over 850 hospitals in the USA using the RAPID software, showed a decrease of 39% [8]. Similar admission trends were observed in the UK where there was also an increase in the average severity of cases arriving in hospital [9]. An analysis of data in a secondary phase of the pandemic in tertiary care unit in Italy showed that the most serious strokes had hospital access rates comparable to previous years and the contraction was mainly in the milder forms [10]. Policies minimizing provider-patient interactions as well as personal reticence to come to the ED during the pandemic might have participated in such contraction, which has prompted international societies to speak up to maintain efficient stroke pathways. At the same time, the pandemic has fostered the use of telemedicine in the field of stroke, disclosing the potential of its implementation transversally, in all treatment stages [11, 12].

The COVID emergency, beyond its tragedy, has been so far an opportunity for a profound reflection on the theme of new digital technologies in the various neurological disciplines [13,14,15,16,17], and the greatest impact could be in the field of stroke. Even if the field of stroke is probably the one in which development of telehealth was greater among all the other neurological disciplines, with a path started several years ago, this pandemic may be a key moment for its large-scale use [18, 19].

The standard course of a subject affected by acute stroke could be divided in 3 phases: hospitalization in a facility for hyperacute and acute care, followed by an intensive rehabilitation phase in a hospital or day-hospital regime and the return home to daily activities with a periodic follow-up [20, 21]. The new telemedicine, gaming, and neurorobotic technologies can play a role in each of these three main phases that represent the medical response to a stroke. The main aim of stroke units and stroke network is to reduce mortality by providing acute patient monitoring, to avoid complications, such as aspiration pneumonia, venous thromboembolism, and pressure sores, and to start early rehabilitation and institute targeted secondary prevention [22, 23].

Consequences of stroke on lost motor functions, language skills, and cognitive deficits cause the inability of a subject to return to daily functions, require assistance from family members or dedicated caregivers, and have significant economic costs for the family and the health system. Implementation of telemedicine in stroke networks was proposed to guarantee standardized expertise in the management of patients and also in remote locations or in conditions with limited access to medical attention [24, 25].

Evidence supporting the equivalence of telestroke to in-person care accumulated over time, with similar rates of stroke mimics, superimposable stroke scale scores (including NIHSS), and, most importantly, with comparable good functional outcome after hyperacute treatment [24, 26,27,28]. Several remote communication tools have been developed to meet the demand of stroke workload on the basis of the shortage of vascular neurologists. Treatment decisions made through apps developed to share clinical and imaging data meant to facilitate and speed up stroke treatment have been shown to be as accurate as in-person evaluation [29]. Thrombectomy services are also evolving to robotic-assisted stage, with telerobotic systems potentially improving neurointervention itself [30, 31]. Such treatment paradigms might become paramount under pandemic circumstances, allowing stroke pathways to proceed limiting the contact of health personnel and allowing for multiple procedures to happen in shorter time.

Digital technology is also entering the field of stroke etiology differentials. In a time where convolutional classifications are facing the need of extensive monitoring [32], and stroke resources are reduced to the essential to leave way to the care of COVID-19, atrial fibrillation (AF) cannot be missed. The diagnosis of AF is crucial to prevent cardioembolic stroke, and therefore paramount to control the burden of recurrent stroke and cerebrovascular disease. Screening for both symptomatic and asymptomatic AF has been demonstrated effective with mechanocardiography, using recordings of mechanical cardiac activity through accelerometers and gyroscopes in smartphones [33]. Photoplethysmography with a smartphone camera has been demonstrated as effective as internet-enabled electrocardiography for AF screening [34]. Automatic real-time detection of AF in non-invasive ECG signals, counting on beat to beat variability, tachogram analysis, and simple signal filtering, has been demonstrated feasible with mobile devices [35], while proper apps built to record a rhythm strip using smartwatches have been shown accurate in differentiating AF from sinus rhythm [36]. Recently, the Apple Heart Study [37] demonstrated the availability of an app for detecting AF in subject without a previous history of this arrhythmia. In over 400,000 participants, notifications for irregular cardiac pulse were sent in 0.52% of the study population and, among them, AF was detected with the ECG in 34% of the cases, thus providing a first evidence for the use of telephone apps in this field.

Telemedicine has critical weight in rehabilitation [38]. Several data from scientific literature have shown that brain plasticity phase after stroke does not end in the first few months and can continue a long time after the acute event if the learning program does not stop [39, 40]. Given the drastic reduction in the offer of rehab services during the pandemic, due to the conversion of facilities to host COVID-19 patients, digital technology can represent a key tool in this phase. On the Google trend engine, searches for the term “telerehab” grew by about 400% in the first week of March 2020 and have reached unprecedented values.

Depending on the availability of the user, the telerehab sessions can be performed by phone, via videoconferencing software or through dedicated apps (i.e., “REHABmyPatient,” “myRehab,” or “RehabPal”).

In conclusion, telemedicine will be included among the major historical changes that the COVID-19 pandemic will bring to clinical practice due to its ability to take care of people, minimizing the use of protective devices and making medical practice safer for operators. Digital technology has consistently been implemented in stroke care in the last few years, as the acute and chronic management of cerebrovascular disease is particularly suitable for telemedicine, especially during the COVID-19 pandemic. The COVID emergency, beyond its tragedy, has been so far an opportunity for a profound reflection on the theme of new digital technologies in the various neurological disciplines [13,14,15,16,17], and the greatest impact could be in the field of stroke.

Acute care can benefit from telemedicine paradigms to guide drip-and-ship models and provide high standards of care even in remote areas. The etiological classification of stroke counts on extensive search of AF, which can nowadays be pursued through dedicated apps and teledetection systems. Finally, efforts should be directed to the implementation of telerehabilitation, which has been demonstrated to provide an extensive benefit for stroke recovery, especially for cortical symptoms and dexterity. During the COVID-19 pandemic, telerehabilitation can be critically useful to limit in-person consultation and provide a tele-hot-pursuit, making optimal secondary prevention and rehabilitation feasible even in lockdown times.