The following data were collected from the study population:

The variables related functional capacity and strength assessment were as follows:

The variables related to a healthy lifestyle used in this work were as follows:

The variables related to the program implementation were as follows:

During their first visit, the potential participants were evaluated for cardiovascular risk factors, adherence to the Mediterranean diet (PREDIMED questionnaire), and emotional status (HADS). In addition, quality of life and exercise training volume were evaluated using the EuroQoL and IPAQ-SF questionnaires, respectively.

Muscle strength was evaluated using the 30-second sit-to-stand (lower limb) and arm curl (upper limb) tests. The intensity prescribed was based on the basal characteristics of each patient and the maximum HR reached on the initial stress test on the treadmill using the Bruce protocol. In some cases with limited functional capacity, we used the modified Bruce protocol [31]. The 85% of maximum HR obtained in the stress test was the maximum HR allowed by the Fitbit device to guide the exercises, as described in the 2020 European Society of Cardiology Guidelines on Sports Cardiology and Exercise in Patients with Cardiovascular Disease [32].

The holistic CRP included 3 weekly exercise sessions and 1 weekly session regarding lifestyle habits, therapeutic adherence, and patient empowerment (Figure 1) for a duration of 8 weeks.

The sessions were performed by a physiotherapist or nurse expert in nutrition in groups of 8 patients. The sessions took place after working hours to increase patient adherence and to be compatible with normal hospital activities.

Each participant completed 24 thrice weekly PT sessions, each lasting 1 hour. The sessions were conducted live via the platform, with guidance from a physiotherapist and cardiologist.

Exercise training consisted of aerobic and prescribed strength training based on the exercise testing and strength assessment; the HR and perceived exertion scale regulated the exercise intensity. The HR was monitored during the PT sessions using a Fitbit Inspire 2 device, which complied with the privacy shield policy. The training load was then increased overnight.

Patients directly contacted their assigned physiotherapist during and up to 30 minutes after the training sessions. In all sessions, there was a responsible cardiologist on call, in case of need. If any complication occurred within the indicated time, the physiotherapist initiated the medical emergency circuit, which consisted of contacting 112 (medical emergency telephone number) and detailing the complication to ensure prompt evaluation of the patient. The cardiologists were simultaneously informed of the adverse event.

All patients were instructed to bring along a family member during the PT sessions. In addition, before starting, all patients and their relatives (partners or caregivers) had to complete a workshop, which was offered live on the platform, on cardiopulmonary resuscitation and warning signs. Moreover, patients could forward their queries and messages through chat. The program physiotherapist reviewed these messages and questions daily and referred the patients to the medical team when necessary (Figure 2).

A specialized nurse accredited in nutrition conducted weekly group sessions through the web-based platform to address issues such as smoking, the Mediterranean diet, patient empowerment, therapeutic adherence, and psychological support, including strategies for acceptance of the disease, to comprehensively improve the quality of life and encourage a healthy lifestyle. In addition, all patients had individual monthly sessions during which the concepts covered during the group sessions were reinforced.

The last visit at the end of the program included a maximal exercise test: upper and lower extremity strength assessments. In addition, questionnaires assessing adherence to the Mediterranean diet, emotional state, quality of life, and medication count were also repeated.

We defined correct adherence if the patient completed the established and individualized protocol and the assistance was >80% of the session's educational and exercise.

CRP significantly improved the maximal and submaximal aerobic capacities, weekly training volume, and muscle strength. In addition, no changes in blood pressure values were observed at rest or during exercise (Table 1).

CRP significantly increased adherence to the Mediterranean diet, promoted a better quality of life, and improved the emotional state by reducing anxiety symptoms; however, no changes were observed in the depressive symptoms (Figure 4).

Adherence to the exercise (85.3%) and educational (86.6%) sessions was excellent. Additionally, there were no significant differences between male and female participants (exercise sessions: P=.10; educational sessions: P=.21; Table 2).

This CRP pilot study included 50 patients after an ischemic event, 42 (85%) of whom were male.

Subgroup analysis showed an equivalent impact of the CRP on maximal aerobic capacity and muscle strength. Similar results were observed for adherence to the Mediterranean diet, quality of life, and depression symptoms, with a greater impact on improving anxiety symptoms (Table 3).

Among the 50 participants who completed the program, 6 (12%) were aged >75 years. In total, 45% (22/50) of the older population initially recruited dropped out because of technical issues, whereas none of the younger participants did so for this reason (Table 4).

In this pilot study, we developed a holistic telematic CRP dedicated to patients after an ischemic cardiac event, including patients of both sexes with no age limit. Our results can be summarized into four key findings: (1) telematic CRP, including tailored aerobic and strength training sessions, improved maximal and submaximal aerobic capacities and muscle strength; (2) a holistic approach, including educational sessions and emotional support, significantly improved adherence to the Mediterranean diet, emotional state, and quality of life; (3) CRP was beneficial irrespective of age and sex; and (4) the telematic CRP strategy was safe and feasible for our study population, although there were differences in the preferences of patients in terms of duration and type of strategy.

In the overall study population, our telematic CRP led to an improvement of 1.6 METs. This increase is equivalent to the reported face-to-face CRP conducted in comparable study populations and with a similar training protocol (a combination of aerobic and resistance training) [34]. In contrast, it was superior to that observed after CRPs that involved only independent aerobic PT during the telematic or face-to-face strategy. Strength training is safe for patients with ischemic heart disease and is synergistic with aerobic exercise training [35]. Furthermore, our PT protocol significantly increased the results of the arm curl (15.5%) and sit-to-stand (19.7%) tests, indirectly measuring the arm and leg muscle strength resistance, respectively. Both aerobic and strength training are essential for exercise-induced beneficial metabolic effects [36]. In addition, muscle strength is known to be strongly correlated with quality of life and autonomy, especially in older adult patients [37]. Therefore, on-site or telematic strength training should be part of all PT protocols in CRPs.

Our comprehensive telematic CRP included nutritional counseling, educational sessions, and emotional support. These interventions enhance patient empowerment by promoting a healthy lifestyle [38,39]. In a recent meta-analysis [40], CRP reduced anxiety and depression rates without differences between face-to-face and telematic strategies. In our study, patients were made cognizant of their disease, after which their anxiety levels significantly decreased. However, no significant changes were observed in depressive symptoms. A meta-analysis reported that the prevalence of depression after acute coronary syndrome in round 14 improved to 3% after cardiac rehabilitation [41]. However, the COVID-19 pandemic increased this percentage to 34% [42]. Our study population had average depression rates of 16.9% preintervention and 15% postintervention; therefore, we hypothesize that this nonsignificant improvement in the post-CRP depression score could have resulted from the COVID-19 pandemic. Meanwhile, anxiety levels positively and significantly improved after the program (23% preintervention and 17% afterward), possibly because of greater empowerment of the patient and improved cognition regarding their disease.

In compliance with the previously mentioned meta-analysis, our holistic CRP, including individual and group nutritional counseling, significantly improved compliance with the Mediterranean diet, which is the best-studied and most evidence-based diet for preventing ischemic events and is considered the gold standard for healthy eating [43]. Moreover, it reduces the risk of repeated cardiovascular events, as evidenced by a previous randomized controlled trial [44]. Therefore, CRP must include nutritional assessments, possibly with the PREDIMED score, and more complements to medical treatment.

Furthermore, home-based CRP significantly improved quality of life, concordant with similar studies on telematic cardiac rehabilitation [45] and center-based CRP [46]. This may be because of patient empowerment regarding their cardiac condition, which allows them to resume their previous daily activities without fear and provides tools for the management of cardiac symptoms and stress.

This CRP pilot study included 50 patients after an ischemic event, 42 (85%) of whom were male. This percentage was similar to that of other studies, and US surveys have shown that following a heart attack, 14.3% of female individuals participated in CRPs compared with 22.1% of male individuals [47]. Female individuals are less likely to engage in CRP than male individuals because of less encouragement from practitioners and psychosocial barriers, such as familial obligations, lack of support, and misperception of the disease [48]. Furthermore, they are usually older and have more comorbidities, increased anxiety and depression, worse functional capacity, and worse CRP results, compared with male individuals [15]. Specific interventions, such as automatic referral, strong physician recommendation, psychological support, and home-based or tailored programs, can increase adherence and improve results in female individuals [49,50].

Our pilot telematic CRP attempted to provide the flexibility of a tailored intervention for female patients and psychological support, which resulted in an equivalent impact of CRP on maximal aerobic capacity and muscle strength and better impact on improving anxiety symptoms (Table 2). Although female patients had higher levels of anxiety preintervention, it could be easier in this group to achieve positive scores, highlighting the special importance of psychological sessions in female patients. Conversely, CRP adherence was similar among male and female patients (Table 3), which differed from the superior adherence observed among male individuals in traditional center-based studies [51].

Of the study participants, 12% (6/50) were aged >75 years and 24% (12/50) had an LVEF of <50%. Although both represented a small percentage of the entire group, these patients had no complications during the intervention. However, CRP use among older patients remains low despite evidence suggesting lower mortality, hospitalization rates, and Medicare costs and improved symptomatology [52]. This may be because of multiple comorbidities; psychosocial factors, such as denial of disease severity and depression; and other difficulties, such as transportation to the CRP centers [53]. Newer CRP models include home-based approaches to overcome these barriers [54]. In addition, CRP benefits patients with low LVEF [55], in whom exercise training is not associated with adverse effects on left ventricular remodeling, and most patients have improved functional capacities despite the LVEF [56]. Both older patients and those with a low LVEF and poor functional class are associated with frailty, which is increased in patients who undergo CRP for acute coronary syndrome [57].

In the subgroup analysis (Table 4), patients aged >75 years had an increase of 1.7 (SD 0.9 METs) in maximal aerobic capacity, which reached statistical significance despite the small study subgroup. Furthermore, CRP induced significant improvements in adherence to the Mediterranean diet and emotional state, and these improvements were better than those observed in younger individuals. No major or minor complications occurred during the intervention in this subgroup. Moreover, no minor or major complications were observed in this study population. Although these results are promising in terms of positive values of CRP for the older population, the feasibility of the telematic approach is low, as 45% of the older population recruited for the program dropped out because of technical issues, whereas none of the younger participants did so for this reason. Overall, these results emphasize that CRP for older patients must be tailored to individual clinical complexities to obtain better outcomes of functional capacity, nutritional status, comorbidities, cognitive status, and socioeconomic support.

Regarding the designed platform, 50% (25/50) of the patients adequately handled it; however, 15% (7/50) still required help. In addition, 83% (41/50) of patients aged >75 years and 40% (20/50) of younger patients faced technological difficulties when using the platform.

Feedback collected from patients and health professionals during the study could enhance the different aspects of the tools that have already been implemented, whereas others will soon be incorporated. In this manner, our solution can be better adapted for people with different technological backgrounds, allowing the inclusion of more patients in such telematic programs.

However, wearable devices do not provide real-time data, which are crucial for monitoring the maximum HR of a patient during telematic rehabilitation sessions.

Therefore, we plan to incorporate new wearable devices into our platform in the future to resolve this problem. If different brands of wearable devices are available to collect data on the platform, patients may already be using them; thus, offering a “bring your own device” approach would be helpful. In addition, some of these devices allow third-party apps to record HRs in real time or with minor delays.

Regarding the preferences for CRP strategies, one-third of the patients preferred the face-to-face approach, one-third preferred the telematic approach, and one-third were comfortable with both strategies. These results emphasize the need for a tailored CRP program that offers different approaches and durations based on patient characteristics and preferences.

Finally, regarding the duration of CRP, one-third of our study population considered a longer CRP necessary for better results. Phase 3 (maintenance) intervention, usually developed between general practitioners and the cardiology team, helps patients maintain their physical activity levels and reduces the risk of new cardiovascular events [58]. However, costs, coordination among different teams, and patient motivation are crucial for its development, which remains a challenge for further improvement.