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Background Smartphone manufacturers offer mobile health monitoring technology to their customers, including apps using the built-in camera for heart rate assessment. This study aimed to test the diagnostic accuracy of such heart rate measuring apps in clinical practice. Methods The feasibility and accuracy of measuring heart rate was tested on four commercially available apps using both iPhone 4 and iPhone 5. 'Instant Heart Rate' (IHR) and 'Heart Fitness' (HF) work with contact photoplethysmography (contact of fingertip to built-in camera), while 'Whats My Heart Rate' (WMH) and 'Cardiio Version' (CAR) work with non-contact photoplethysmography. The measurements were compared to electrocardiogram and pulse oximetry-derived heart rate. Results Heart rate measurement using app-based photoplethysmography was performed on 108 randomly selected patients. The electrocardiogram-derived heart rate correlated well with pulse oximetry ( r = 0.92), IHR ( r = 0.83) and HF ( r = 0.96), but somewhat less with WMH ( r = 0.62) and CAR ( r = 0.60). The accuracy of app-measured heart rate as compared to electrocardiogram, reported as mean absolute error (in bpm ± standard error) was 2 ± 0.35 (pulse oximetry), 4.5 ± 1.1 (IHR), 2 ± 0.5 (HF), 7.1 ± 1.4 (WMH) and 8.1 ± 1.4 (CAR). Conclusions We found substantial performance differences between the four studied heart rate measuring apps. The two contact photoplethysmography-based apps had higher feasibility and better accuracy for heart rate measurement than the two non-contact photoplethysmography-based apps.

Aims: Elderly patients with sinus node dysfunction (SND) are at increased risk of falls with possible injuries. However, the incidence of these adverse events and its reduction after permanent pacemaker (PPM) implantation are not known., Methods and Results: Eighty-seven patients (mean [SD] age 75.4 [8.3] years, 51% women) with SND and an indication for cardiac pacing were included and were examined by a standardized interview targeting fall history. The incidence and total number of falls, falls with injury, falls requiring treatment, and falls resulting in a fracture were assessed for the time period of 12 months before (retrospectively) and after PPM implantation (prospectively). Furthermore, symptoms such as syncope, dizziness, and dyspnea were evaluated before and after PPM implantation. The implantation of a PPM was associated with a reduced proportion of patients experiencing at least one fall by 71% (from 53 to 15%, P < 0.001) and a reduction of the absolute number of falls by 90% (from 127 to 13, P < 0.001) during the 12 months before vs. after PPM implant. Falls with injury (28 vs. 10%, P = 0.005), falls requiring medical attention (31 vs. 8%, P < 0.001), and falls leading to fracture (8 vs. 0%, P = 0.013) were similarly reduced. Notably, fewer patients had syncope (4 vs. 45%, P < 0.001) and dizziness after PPM implantation (12 vs. 45%, P < 0.001)., Conclusion: Falls, fall-related injuries, and fall-related fractures are frequent in SND patients. Permanent pacemaker implantation is associated with a significantly reduced risk of these adverse events, although no causal relationship could be established due to the study design., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.)

Aims: Catheter-based renal nerve ablation (RNA) using radiofrequency energy is a novel treatment for drug-resistant essential hypertension. However, the local endothelial and vascular injury induced by RNA has not been characterized, although this importantly determines the long-term safety of the procedure. Optical coherence tomography (OCT) enables in vivo visualization of morphologic features with a high resolution of 10-15 µm. The objective of this study was to assess the morphological features of the endothelial and vascular injury induced by RNA using OCT., Methods and Results: In a prospective observational study, 32 renal arteries of patients with treatment-resistant hypertension underwent OCT before and after RNA. All pre- and post-procedural OCT pullbacks were evaluated regarding vascular changes such as vasospasm, oedema (notches), dissection, and thrombus formation. Thirty-two renal arteries were evaluated, in which automatic pullbacks were obtained before and after RNA. Vasospasm was observed more often after RNA then before the procedure (0 vs. 42%, P < 0.001). A significant decrease in mean renal artery diameter after RNA was documented both with the EnligHTN (4.69 ± 0.73 vs. 4.21 ± 0.87 mm; P < 0.001) and with the Simplicity catheter (5.04 ± 0.66 vs. 4.57 ± 0.88 mm; P < 0.001). Endothelial-intimal oedema was noted in 96% of cases after RNA. The presence of thrombus formations was significantly higher after the RNA then before ablation (67 vs. 18%, P < 0.001). There was one evidence of arterial dissection after RNA with the Simplicity catheter, while endothelial and intimal disruptions were noted in two patients with the EnligHTN catheter., Conclusion: Here we show that diffuse renal artery constriction and local tissue damage at the ablation site with oedema and thrombus formation occur after RNA and that OCT visualizes vascular lesions not apparent on angiography. This suggests that dual antiplatelet therapy may be required during RNA.

Background: Diabetes mellitus (DM) type 1 is an important contributor to end-stage renal disease (ESRD) among younger transplant recipients. However, little is known about the changes in epidemiological characteristics of this population. Especially, time to reach ESRD may have changed in type 1 diabetic patients referred for transplantation, resulting in higher age at time of grafting. Such time trends may allow anticipating future developments regarding the demand for organ replacement in this patient group., Methods: We retrospectively analysed 173 patients with type 1 DM undergoing renal transplantation at our institution, stratified into four groups according to year of reaching ESRD (A = 1973-1983, B = 1984-1990, C = 1991-1995 and D = 1996-2002). For each group we determined age at diagnosis of DM, age at time of reaching ESRD and age at time of transplantation. From these data, the interval from diagnosis of DM to ESRD and from ESRD to transplantation was calculated. The results were analysed in relation to gender, year of and age at onset of diabetes., Results: Patients reaching ESRD in more recent years (group D) tended to be both younger at diagnosis of DM and older when reaching ESRD, resulting in higher mean age at transplantation (35.0, 37.5, 39.6 and 41.0 years in groups A, B, C and D, respectively). Accordingly, median duration to ESRD has significantly been prolonged over the last five decades in patients with type 1 DM undergoing renal transplantation (group A: 21.0, B: 20.7, C: 22.3 and D: 28.5 years; P < 0.0001), this finding being more pronounced in female patients., Conclusions: The results of our analysis are compatible with a change in epidemiology in patients undergoing kidney transplantation. Older age at time of reaching ESRD may impact significantly on the demand for renal grafts, as patients are already clearly older nowadays when being transplanted. From our data it cannot be concluded whether this development is due to a change in the progression of diabetic nephropathy or may simply reflect a change in the selection of type 1 diabetic patients referred for transplantation.

Objective: Arterial perfusion through the right subclavian artery is proposed to avoid intraoperative malperfusion during repair of acute type A dissection. This study evaluated the clinical and neurological outcome of patients undergoing surgery of acute aortic type A dissection following subclavian arterial cannulation compared to femoral artery approach., Methods: From 1/97 to 1/03, 122 consecutive patients underwent surgery for acute type A aortic dissection. Subclavian cannulation was performed in 62 versus femoral cannulation in 60 patients. Clinical characteristics in both groups were similar. Mean age was 61 years (SD+/-14 years, 72% male) and mean follow-up was 3 years (+/-2 years). Patient outcome was assessed as the prevalence of clinical complications, especially neurological deficits, mortality at 30 days, perioperative morbidity and time of body temperature cooling and analyzed by nominal logistic regression analysis for odds ratio calculation., Results: Arterial subclavian cannulation was successfully performed without any occurrence of malperfusion in all cases. Patients undergoing subclavian cannulation showed an odds ratio of 1.98 (95% CI 1.15-3.51; P=0.0057) for an improved neurological outcome compared to patients undergoing femoral cannulation. Re-exploration rate for postoperative bleeding was significantly reduced in the subclavian group (P<0.0001), as well as occurrence of myocardial infarction (P<0.0001) and duration for body temperature cooling (P=0.004). The 30-day mortality of patients with femoral cannulation was significantly higher compared to patients with subclavian artery cannulation (24 versus 8%; P=0.0179)., Conclusions: Arterial perfusion through the right subclavian artery provides an excellent approach for repair of acute type A dissection with optimized arterial perfusion body perfusion and allows for antegrade cerebral perfusion during circulatory arrest. The technique is safe and results in a significantly improved clinical and especially neurological outcome.

Improved survival after myocardial infarction (MI) could result in MI survivors' contributing to the US heart failure epidemic. Conversely, since the severity of MI is declining over time, a decline in post-MI heart failure might also be anticipated. This study tested the hypothesis that the incidence of post-MI heart failure was declining over time in a geographically defined MI incidence cohort. Between 1979 and 1994, 1,537 patients with incident MI and no prior history of heart failure were hospitalized in Olmsted County, Minnesota. Framingham Heart Study criteria were used to ascertain the incidence of inpatient and outpatient heart failure over a mean follow-up period of 7.6 years (standard deviation 5.5). Overall, 36% of patients experienced heart failure. After adjustment for factors related to post-MI heart failure (age, hypertension, smoking, and biomarkers), the incidence of heart failure declined by 2% per year (relative risk = 0.98, 95% confidence interval: 0.96, 0.99; p = 0.01). The relative risk of developing heart failure among persons with MIs occurring in 1994 versus 1979 was 0.72 (95% confidence interval: 0.55, 0.93), indicating a 28% reduction in the incidence of heart failure. Administration of reperfusion therapy within 24 hours after MI was associated with lower risk of post-MI heart failure and accounted for most of the temporal decline in heart failure. This suggests that improved survival after MI is unlikely to be a major contributor to the heart failure epidemic.

The mechanisms of the decline in coronary heart disease mortality are not fully elucidated. In particular, little is known about the trends in severity of myocardial infarction, which may have contributed to the mortality decline. This study examines indicators of myocardial infarction severity including Killip class, electrocardiogram descriptors, and peak creatine kinase values in a population-based, myocardial infarction incidence cohort to test the hypothesis that the severity of myocardial infarction declined over time. Between 1983 and 1994, 1,295 incident cases of myocardial infarction (mean age, 67 (standard deviation, 6) years; 43% women) occurred in Olmsted County, Minnesota. The median time between the onset of symptoms and presentation was 1.9 (interquartile range, 3.9) hours and declined over time (p = 0.018), while the use of reperfusion therapy increased. Over time, the hemodynamic presentation of patients did not change appreciably, but the proportion of persons with ST-segment elevation declined as did the occurrence of Q waves and peak creatine kinase values. These secular trends, which were largely independent from the time to first electrocardiogram and reperfusion therapy, indicate a decline in the severity of myocardial infarction over time.