Although many studies have been conducted to confirm adherence with noninvasive telemonitoring (Supplemental Table 1),7 the present study is the first to investigate the feasibility of noninvasive, multi-parametric, self-telemonitoring using multiple devices including a heart sound recorder. The findings of the present study included: (1) even with multiple devices, self-telemonitoring was feasible, with 87% of patients feeling self-telemonitoring was helpful; (2) poor adherence was significantly associated with younger age and higher MLHFQ scores; and (3) self-telemonitoring found a significant increase in heart rate and diastolic BP, as well as a decrease in QoS2, before the HF events.
One of the major barriers to implementing self-monitoring in daily clinical practice is the poor feasibility of continuing troublesome self-monitoring by patients living with their own busy lifestyles. Although the effect of lifestyle on adherence in heart failure telemonitoring is difficult to estimate, some studies have also reported a trend for lower adherence at younger ages.17,18 Even a combination of simple procedures, each of which takes only one to two minutes, might become a significant burden if they have to be repeated and continued every day for a long time, especially for patients with impaired functional capacity. However, the present results showed that noninvasive, multi-parametric, self-telemonitoring using a handheld heart sound recorder was feasible for the majority of patients with HF. The underlying mechanisms of the feasibility found in the present study may be explained by the results of the questionnaire; they demonstrated that self-telemonitoring provided patients with a sense of relief and a sense of control over their own health status. This empowerment, coupled with the convenience and ease of use of the handheld recorder, may have contributed to the high patient satisfaction rates and the overall feasibility of the self-telemonitoring method.
The findings of the present study suggest that younger patients and those with higher MLHFQ tended to be less adherent to the self-telemonitoring method. This may be due to several reasons; younger patients may have less motivation or interest in their health status, and/or more competing demands, such as work or family responsibilities, that may limit their ability to engage in self-monitoring activities. Patients with higher MLHFQ may also have limited physical ability, which makes them feel more burdened by the measurements. Therefore, tailored interventions targeting these specific populations may be necessary to improve adherence rates and the effectiveness of self-telemonitoring in managing HF.
In the present study, two parameters showed significant changes from the baseline period to the week just before HF events. In particular, the observed decrease in QoS2, the time interval from Q wave onset to the second heart sound, before HF events might be an important finding, which was in line with our previous report.11 In the previous study, QoS2 measured by a portable digital stethoscope increased in the acute phase of HF hospitalization as patients’ conditions changed, and the increase in QoS2 was correlated with the increase in the stroke volume index of echocardiography. Although the underlying physiological mechanism is yet to be investigated, QoS2 may be a sensitive and important marker of worsening HF.
As for the clinical impact of the present findings, noninvasive, multi-parametric, self-telemonitoring using a handheld heart sound recorder may be a valuable tool in the management of patients with HF. The ability of patients to monitor their condition at home may provide an opportunity for early intervention and prevent disease progression, thus reducing hospitalizations and healthcare costs. In addition, the identification of factors associated with poor adherence, such as younger age and higher MLHFQ scores, may allow for targeted interventions to improve the adherence rate and the effectiveness of the self-telemonitoring method. Further studies are needed to validate the present findings and assess the long-term clinical outcomes of self-telemonitoring in patients with HF.
Limitations
The present study includes some limitations. First, the number of patients was too small to set clinical events as the primary outcome. Although significant changes in parameters including QoS2 were observed before HF events, these results should be considered hypothesis-generating. Second, the study included only university hospitals. Patients who visit university hospitals may pay more attention to their health status, and thus may have higher adherence rates.