Safety, Feasibility, and Acceptability of Telemedicine for Hypertension in Primary Care: A Proof-of-concept and Pilot Randomized Controlled Trial (SATE-HT).

Hypertension (HT) continues to be a leading cause of cardiovascular death and an enormous burden on the healthcare system. Although telemedicine may provide improved blood pressure (BP) monitoring and control, it remains unclear whether it could replace face-to-face consultations in patients with optimal BP control. We hypothesized that an automatic drug refill coupled with a telemedicine system tailored to patients with optimal BP would lead to non-inferior BP control. In this pilot, multicenter, randomized control trial (RCT), participants receiving anti-HT medications were randomly assigned (1:1) to either the telemedicine or usual care group. Patients in the telemedicine group measured and transmitted their home BP readings to the clinic. The medications were refilled without consultation when optimal control (BP < 135/85 mmHg) was confirmed. The primary outcome of this trial was the feasibility of using the telemedicine app. Office and ambulatory BP readings were compared between the two groups at the study endpoint. Acceptability was assessed through interviews with the telemedicine study participants. Overall, 49 participants were recruited in 6 months and retention rate was 98%. Participants from both groups had similar BP control (daytime systolic BP: 128.2 versus 126.9 mmHg [telemedicine vs. usual care], p = 0.41) and no adverse events. Participants in the telemedicine group had fewer general outpatient clinic attendances (0.8 vs. 2, p < 0.001). Interviewees reported that the system was convenient, timesaving, cost saving, and educational. The system could be safely used. However, the results must be verified in an adequately powered RCT. Trial registration: NCT04542564.

Long term clinical outcomes of patients with ischemic stroke in primary care - a 9-year retrospective study.

BACKGROUND: We aim to document the long-term outcomes of ischemic stroke patients and explore the potential risk factors for recurrent cardiovascular events and all-cause mortality in primary care. METHODS: A retrospective cohort study performed at two general out-patient clinics (GOPCs) under Hospital Authority (HA) in Hong Kong (HK). Ischemic stroke patients with at least two consecutive follow-up visits during the recruitment period (1/1-30/6/2010) were included. Patients were followed up regularly till the date of recurrent stroke, cardiovascular event, death or 31/12/2018. The primary outcome was the occurrence of recurrent cerebrovascular event including transient ischemic stroke (TIA), ischemic stroke or hemorrhagic stroke. The secondary outcomes were all-cause mortality and coronary artery disease (CAD). We fit cox proportional hazard model adjusting death as competing risk factor to estimate the cause-specific hazard ratio (csHR). RESULTS: A total of 466 patients (mean age, 71.5 years) were included. During a median follow-up period of 8.7 years, 158 patients (33.9%) died. Eighty patients (17.2%) had recurrent stroke and 57 (12.2%) patients developed CAD. Age was an independent risk factor for recurrent stroke, CAD and death. Statin therapy at baseline had a protective effect for recurrent stroke (csHR = 0.476; 95% confidence interval [CI] 0.285-0.796, P = 0.005) after adjusting death as a competing risk factor and all-cause mortality (HR = 0.693, 95% CI 0.486-0.968, P = 0.043). In addition, female sex, antiplatelet and a higher diastolic blood pressure (DBP) at baseline were also independent predictors for survival. CONCLUSIONS: Long term prognosis of ischemic stroke patients in primary care is favorable. Use of statin was associated with a significant decrease in stroke recurrence and mortality. Patients who died had a significant lower DBP at baseline, highlighted the need to consider both systolic and diastolic blood pressure in our daily practice.

Enhancing cerebral perfusion with external counterpulsation after ischaemic stroke: how long does it last?

OBJECTIVE: External counterpulsation (ECP) is a non-invasive method used to augment cerebral perfusion in ischaemic stroke. We aimed to investigate time-course effects on blood pressure elevation and cerebral blood flow augmentation induced by ECP in ischaemic stroke. METHODS: Patients with acute unilateral ischaemic stroke and large artery occlusive disease were recruited to receive 35 daily 1 h ECP treatment sessions. Serial transcranial Doppler monitoring of bilateral middle cerebral arteries was performed on days 3, 5, 7, 10, 14, 21, 28 and 35 after stroke onset. Flow velocity changes before, during and after ECP and continuous beat-to-beat blood pressure data were recorded. The cerebral augmentation index (CAI) is the increase in the percentage of the middle cerebral artery mean flow velocity during ECP compared with baseline. RESULTS: The CAI in patients with stroke was significantly higher on the ipsilateral side and on the contralateral side on day 3 (ipsilateral CAI, 9.3%; contralateral CAI, 7.2%), day 5 (7.0%; 6.7%), day 7 (6.8%; 6.0%), day 10 (6.0%; 5.1%), day 14 (4.7%; 2.6%) and day 21 (4.1%; 2.2%) after stroke onset than that in controls (-2.0%) (all p<0.05). There was a significant trend of decreasing CAI on the ipsilateral and contralateral sides over time after a stroke. Differences in the percentage increase in the mean blood pressure did not change significantly over time in patients with stroke. CONCLUSIONS: Blood pressure elevation persists throughout ECP treatment, which consists of 35 sessions. However, cerebral blood flow augmentation may last at least 3 weeks and then appears to return to baseline 1 month after acute stroke onset.

External counterpulsation augments blood pressure and cerebral flow velocities in ischemic stroke patients with cerebral intracranial large artery occlusive disease.

BACKGROUND AND PURPOSE: External counterpulsation (ECP) is a novel noninvasive method used to improve the perfusion of vital organs, which may benefit ischemic stroke patients. We hypothesized that ECP may augment cerebral blood flow of ischemic stroke patients via induced hypertension. METHODS: We recruited ischemic stroke patients with cerebral intracranial large artery occlusive disease and healthy elderly controls into this study. Bilateral middle cerebral arteries of subjects were monitored using transcranial Doppler. Flow velocity changes before, during, and after ECP were, respectively, recorded for 3 minutes while continuous beat-to-beat blood pressure data were recorded. Cerebral augmentation index was the increase in percentage of middle cerebral artery mean flow velocity during ECP compared with baseline. Transcranial Doppler data were analyzed based on ipsilateral or contralateral to the infarct side. RESULTS: ECP significantly increased mean blood pressure of stroke patients and controls. During ECP, middle cerebral artery mean flow velocities of stroke patients increased on both ipsilateral and contralateral sides when compared with baseline (ipsilateral cerebral augmentation index, 9.64%; contralateral cerebral augmentation index, 9%; both P<0.001), but there was no increase in difference between the 2 sides when compared with each other. Mean flow velocities of controls did not change under ECP. After ECP, blood pressure and flow velocity of stroke patients returned to baseline level. CONCLUSIONS: ECP provides a new method of cerebral blood flow augmentation in ischemic stroke by elevation of blood pressure. Flow augmentation induced by ECP suggests the improvement of cerebral perfusion and collateral supply from infarct ipsilateral and contralateral sides.

External Counterpulsation Reduces Beat-to-Beat Blood Pressure Variability When Augmenting Blood Pressure and Cerebral Blood Flow in Ischemic Stroke.

BACKGROUND AND PURPOSE: External counterpulsation (ECP) is a noninvasive method used to enhance cerebral perfusion by elevating the blood pressure in ischemic stroke. However, the response of the beat-to-beat blood pressure variability (BPV) in ischemic stroke patients during ECP remains unknown. METHODS: We enrolled recent ischemic stroke patients and healthy controls. Changes in the blood flow velocities in bilateral middle cerebral arteries and the continuous beat-to-beat blood pressure before, during, and after ECP were monitored. Power spectral analysis revealed that the BPV included oscillations at very low frequency (VLF; <0.04 Hz), low frequency (LF; 0.04-0.15 Hz), and high frequency (HF; 0.15-0.40 Hz), and the total power spectral density (TP; <0.40 Hz) and LF/HF ratio were calculated. RESULTS: We found that ECP significantly increased the systolic and diastolic blood pressures in both stroke patients and controls. ECP decreased markedly the systolic and diastolic BPVs at VLF and LF and the TP, and the diastolic BPV at HF when compared with baseline. The decreases in diastolic and systolic BPV reached 37.56% and 23.20%, respectively, at VLF, 21.15% and 12.19% at LF, 8.76% and 16.59% at HF, and 31.92% and 23.62% for the total TP in stroke patients, which did not differ from those in healthy controls. The change in flow velocity on the contralateral side was positively correlated with the total TP systolic BPV change induced by ECP (r=0.312, p=0.035). CONCLUSIONS: ECP reduces the beat-to-beat BPV when increasing the blood pressure and cerebral blood flow velocity in ischemic stroke patients. ECP might be able to improve the clinical outcome by decreasing the beat-to-beat BPV in stroke patients, and this should be explored further in future studies.

A retrospective pilot study of correlation of cerebral augmentation effects of external counterpulsation with functional outcome after acute ischaemic stroke.

OBJECTIVE: External counterpulsation (ECP) is a non-invasive method used to augment cerebral blood flow of patients with ischaemic stroke via induced hypertension. We aimed to explore the correlation between the cerebral blood flow augmentation effects induced by ECP and clinical outcome after acute ischaemic stroke. METHODS: We retrospectively analysed our ECP registry of patients with ischaemic stroke who were enrolled within 7 days after stroke onset. Bilateral middle cerebral arteries of patients were monitored using transcranial Doppler (TCD). Flow velocity changes before, during and after ECP were, respectively, recorded for 3 min. The cerebral augmentation index (CAI) was the increase in percentage of the middle cerebral artery mean flow velocity during ECP compared with baseline. TCD data were analysed based on the side ipsilateral or contralateral to the infarct. The modified Rankin Scale (mRS) (good outcome: mRS 0∼2; poor outcome: mRS 3∼6) was evaluated 6 months after the index stroke. RESULTS: 72 patients were included (mean age, 63.8±10.7 years; 87.5% males). At month 6 after stroke onset, univariate analysis showed that the National Institutes of Health Stroke Scale at recruitment was significantly higher and ECP therapy duration was longer in the poor outcome group, while the ipsilateral CAI was significantly lower in the good outcome group than that in the poor outcome group (3.71±4.94 vs 7.73±7.66, p=0.044). Multivariate logistic regression showed that ipsilateral CAI was independently correlated with an unfavourable functional outcome after adjusting for confounding factors. CONCLUSIONS: The higher degree of cerebral blood flow velocity augmentation on the side ipsilateral to the infarct induced by ECP is independently correlated with an unfavourable functional outcome after acute ischaemic stroke.

The reduction of regional cerebral blood flow in normal-appearing white matter is associated with the severity of white matter lesions in elderly: a Xeon-CT study.

White matter lesions (WMLs) in normal elderly are related to chronic ischemia, and progression of WML occurs mostly in moderate to severe disease. However, the mechanism is uncertain. Thus, we enrolled fifty-six normal elderly patients without large artery disease. The severity of WML on MRI was graded as grade 0, I, II and III using the modified Fazekas scale. Cerebral blood flow (CBF) was measured by Xenon-CT. We found that CBF (mL/100 g/min) within periventricular lesions and in the right and left centrum semiovales were 20.33, 21.27 and 21.03, respectively, in group I; 16.33, 15.55 and 15.91, respectively, in group II; and 14.05, 14.46 and 14.23, respectively, in group III. CBF of normal-appearing white matter (NAWM) around periventricular areas and in the right and left centrum semiovales were 20.79, 22.26 and 22.15, respectively, in group 0; 21.12, 22.17 and 22.25, respectively, in group I; 18.02, 19.45 and 19.62, respectively, in group II; and 16.38, 18.18 and 16.74, respectively, in group III. Significant reductions in CBF were observed not only within lesions but also in NAWM surrounding the lesions. In addition, CBF was reduced significantly within lesions compared to NAWM of the same grade. Furthermore, CBF was reduced significantly in NAWM in grades II and III when compared to grades 0 and I. Our finding indicates that ischemia may play a role in the pathogenesis of WML. Additionally, our finding provides an alternative explanation for finding that the progression of WML occurred more commonly in patients with moderate to severe WML.

Increasing pressure of external counterpulsation augments blood pressure but not cerebral blood flow velocity in ischemic stroke.

External counterpulsation (ECP) is a noninvasive method used to augment cerebral perfusion but the optimal use of ECP in ischemic stroke has not been well documented. We aimed to investigate the effects of ECP treatment pressure on cerebral blood flow and blood pressure (BP). We recruited 38 ischemic stroke patients with large artery occlusive disease and 20 elderly controls. We commenced ECP treatment pressure at 150 mmHg and gradually increased to 187.5, 225 and 262.5 mmHg. Mean cerebral blood flow velocities (CBFV) of bilateral middle cerebral arteries and continuous beat-to-beat BP were recorded before ECP and during each pressure increment for 3 minutes. Patient CBFV data was analyzed based on whether it was ipsilateral or contralateral to the infarct. Mean BP significantly increased from baseline in both stroke and control groups after ECP commenced. BP increased in both groups following raised ECP pressure and reached maximum at 262.5 mmHg (patients 16.9% increase versus controls 16.52%). The ipsilateral CBFV of patients increased 5.15%, 4.35%, 4.55% and 3.52% from baseline under the four pressures, respectively. All were significantly higher than baseline but did not differ among different ECP pressures; contralateral CBFV changed likewise. Control CBFV did not increase under variable pressures of ECP. ECP did increase CBFV of our patients to a roughly equal degree regardless of ECP pressure. Among the four ECP pressures tested, we recommend 150 mmHg as the optimal treatment pressure for ischemic stroke due to higher risks of hypertension-related complications with higher pressures.

Predictors of good functional outcome in counterpulsation-treated recent ischaemic stroke patients.

OBJECTIVES: External counterpulsation (ECP) is a non-invasive method being investigated for ischaemic stroke. We aimed to explore predictors of good functional outcome for ECP-treated ischaemic stroke patients who completed a minimum of 10 sessions. METHODS: We analysed our ECP registry of ischaemic stroke patients with cerebral large artery stenosis who underwent ECP therapy at the Prince of Wales Hospital from 2004 to 2010. We included 155 patients who completed at least 10 sessions of ECP and had 3-month follow-up data as well as 52 medical controls. Functional outcomes were dichotomised into good outcome (modified Rankin Scale (mRS) 0-2) and bad outcome (mRS 3-6). We compared the differences in two groups in terms of demographics, medical history and parameters of ECP treatment. RESULTS: At 3 months after stroke, 70.5% of patients who finished the whole course of ECP had a good outcome (only 46.5% in the unfinished group and 38.5% in the medical group). Among all 207 recruited cases, 119 (57.5%) patients had a good outcome at 3 months after stroke. Compared with the bad outcome group, patients in the good outcome group were younger and had a lower baseline National Institutes of Health Stroke Scale (NIHSS) and longer ECP therapy duration. Multivariate logistic regression showed that ECP duration (OR 1.032), baseline NIHSS (OR 0.734) and age (OR 0.961) were independent predictors for a favourable outcome. CONCLUSIONS: Duration of ECP therapy is first found to be an important predictor for good outcome of ECP-treated ischaemic stroke patients, in addition to the well-known prognostic factors such as age and NIHSS.