Performance and usability evaluation of a mobile health data capture application in clinical cancer trials follow-up.

Mobile health data capture applications (mHDA's) may improve communication between healthcare providers and patients. However, there is limited literature about the use of mHDA's facilitating clinical trials. In this study, the effectiveness of an application, supporting follow-up visits of cancer trial participants was investigated. Twenty participants were provided with an e-questionnaire via the mHDA. Participants rated the usability of the application as high performing (mean Systems Usability Scale 87 points). The research team rated the mHDA as highly applicable and efficient in preparing visits. Anamnesis, physical examination and agreement on further policy were performed within an average of 31 min.

10 kHz Spinal Cord Stimulation for the Treatment of Failed Back Surgery Syndrome with Predominant Leg Pain: Results from a Prospective Study in Patients from the Dutch Healthcare System.

INTRODUCTION: Persistent back/and or leg pain is a common outcome after spinal surgery (otherwise known as failed back surgery syndrome [FBSS]). Studies have shown that spinal cord stimulation (SCS) at 10 kHz provides effective analgesia in FBSS patients with both back and leg pain symptoms and in those with predominant back pain. This study is the first to evaluate the therapy in FBSS patients with predominant leg pain. METHODS: The safety and efficacy of 10 kHz SCS was evaluated in an uncontrolled, open-label, prospective study of FBSS patients with predominant leg pain in the Netherlands. Follow-ups were performed at 1, 3, 6, and 12 months post implantation. RESULTS: Sixty out of 68 patients (88%) experienced sufficient pain relief during a stimulation trial. Of these, 58 proceeded to permanent implantation of a 10 kHz SCS system. After 12 months of treatment, 80% of patients experienced ≥ 50% reduction in baseline leg pain, and a similar proportion (76%) experienced ≥ 50% reduction in baseline back pain. At least two-thirds of patients were also leg pain and back pain remitters (visual analog scale [VAS] ≤ 2.5 cm). The therapy was also associated with a general improvement in patients' quality of life, as measured by secondary outcomes including disability, perception of health improvement, mental well-being, and satisfaction. A positive impact on opioid consumption was also observed. CONCLUSIONS: Consistent with previous findings, 10 kHz SCS for the treatment of FBSS patients with predominant radicular symptoms is safe and effective and is associated with improved quality of life.

Sympathetic Response and Outcomes Following Renal Denervation in Patients With Chronic Heart Failure: 12-Month Outcomes From the Symplicity HF Feasibility Study.

BACKGROUND: Heart failure (HF) is associated with chronic sympathetic activation. Renal denervation (RDN) aims to reduce sympathetic activity by ablating the renal sympathetic nerves. We investigated the effect of RDN in patients with chronic HF and concurrent renal dysfunction in a prospective, multicenter, single-arm feasibility study. METHODS AND RESULTS: Thirty-nine patients with chronic systolic HF (left ventricular ejection fraction [LVEF] <40%, New York Heart Association class II-III,) and renal impairment (estimated glomerular filtration rate [eGFR; assessed with the use of the Modification of Diet in Renal Disease equation] < 75 mL • min-1 • 1.73 m-2) on stable medical therapy were enrolled. Mean age was 65 ± 11 years; 62% had ischemic HF. The average number of ablations per patient was 13 ± 3. No protocol-defined safety events were associated with the procedure. One subject experienced a renal artery occlusion that was possibly related to the denervation procedure. Statistically significant reductions in N-terminal pro-B-type natriuretic peptide (NT-proBNP; 1530 ± 1228 vs 1428 ± 1844 ng/mL; P = .006) and 120-minute glucose tolerance test (11.2 ± 5.1 vs 9.9 ± 3.6; P = .026) were seen at 12 months, but there was no significant change in LVEF (28 ± 9% vs 29 ± 11%; P= .536), 6-minute walk test (384 ± 96 vs 391 ± 97 m; P= .584), or eGFR (52.6 ± 15.3 vs 52.3 ± 18.5 mL • min-1 • 1.73 m-2; P= .700). CONCLUSIONS: RDN was associated with reductions in NT-proBNP and 120-minute glucose tolerance test in HF patients 12 months after RDN treatment. There was no deterioration in other indices of cardiac and renal function in this small feasibility study.

Haemodynamic effects of different basic heart rates in ambulatory heart failure patients treated with cardiac resynchronization therapy.

AIMS: The impact of different basic paced heart rates (pHRs) in patients receiving cardiac resynchronization therapy (CRT) remains largely unknown. The aim of the present study was to investigate the haemodynamic effects of different pHRs (60 or 80 b.p.m.), using an implanted haemodynamic monitor (IHM), during a 2-week period in ambulatory CRT patients. METHODS AND RESULTS: Ten CRT patients received an IHM (Chronicle(®), Medtronic Inc.) to continuously record right ventricular systolic (RVSP) and diastolic (RVDP) pressure, as well as estimated pulmonary artery diastolic pressure (ePAD) during a 2-week period at two basic pHR programming (60 and 80 b.p.m.). Cardiac output (CO) was calculated using a validated IHM algorithm. At the end of each period, 6 min walk test (6MWT), quality of life (QoL), and plasma levels of brain natriuretic peptide (BNP) were also assessed. Pacing at 80 b.p.m. significantly reduced the 2-week average of ePAD compared with 60 b.p.m. (23.4 ± 6.2 vs. 25.1 ± 6.5 mmHg, P = 0.03), whereas CO was increased (4.5 ± 1.3 vs. 4.2 ± 1.4 L/min; P = 0.01). Similarly ePAD, RVSP, and RVDP were significantly lower with a pHR of 80 b.p.m. (P < 0.05). The 6MWT, QoL score, and BNP were not affected by the pHR. CONCLUSION: In CRT patients, a basic pHR of 80 b.p.m. compared with 60 b.p.m. reduces filling pressures and increases CO during a 2-week period of ambulatory living. This suggests that increasing the basic pHR may be considered to achieve short-term haemodynamic improvement. The long-term effects of differential pHR programming remain to be established.

Continuous monitoring of intrathoracic impedance and right ventricular pressures in patients with heart failure.

BACKGROUND: Hemodynamic monitoring using implantable devices may provide early warning of volume overload in patients with heart failure (HF). This study was designed to prospectively compare information from intrathoracic impedance monitoring and continuous right ventricular pressure measurements in patients with HF. METHODS AND RESULTS: Sixteen patients with HF (age, 63.5+/-13.8 years; left ventricular ejection fraction, 23.2+/-11.3%; New York Heart Association, II and III) and a previous HF decompensation received both a cardiac resynchronization therapy defibrillator providing a daily average of intrathoracic impedance and an implantable hemodynamic monitor providing an estimate of the pulmonary artery diastolic pressure. At the end of a 6-month investigator-blinded period, baseline reference hemodynamic values were determined over 4 weeks during which the patient was clinically stable. A major HF event was defined as HF decompensation requiring hospitalization, IV diuretic treatment, or leading to death. Sixteen major HF events occurred in 10 patients. Within 30 days and 14 days before a major HF event, impedance decreased by 0.12+/-0.21 Omega/d and 0.20+/-0.20 Omega/d, respectively, whereas estimated pulmonary arterial diastolic pressure increased by 0.10+/-0.20 mm Hg/d and 0.16+/-0.15 mm Hg/d, respectively. During these periods, impedance decreased by 3.8+/-5.4 Omega (P<0.02) and 4.9+/-6.1 Omega (P<0.007), respectively, whereas estimated pulmonary arterial diastolic pressure increased by 5.8+/-5.7 mm Hg (P<0.002) and 6.8+/-6.1 mm Hg (P<0.001), respectively, compared with baseline. In all patients, impedance and estimated pulmonary arterial diastolic pressure were inversely correlated (r = -0.48+/-0.25). Within 30 days preceding a major HF event, this correlation improved to r =-0.58+/-0.24. CONCLUSIONS: Decompensated HF develops based on hemodynamic derangements and is preceded by significant changes in intrathoracic impedance and right ventricular pressures during the month prior to a major clinical event. Impedance and pressure changes are moderately correlated. Future research may establish the complementary contribution of both parameters to guide diagnosis and management of patients with HF by implantable devices.