Verve Medical | Date: 2015-07-24
A target peripheral nerve is treated by providing a real-time fluorescent image of a tissue region where the target peripheral nerve has an enhanced appearance in the fluorescent image. A treatment element is advanced from an adjacent body lumen or cavity through the tissue region or externally aimed toward the peripheral nerve while viewing the fluorescent image, and the peripheral nerve is treated using the treatment element.
Verve Medical | Date: 2012-07-12
Apparatus, systems, and methods provide access to the renal pelvis of a kidney to treat renal nerves embedded in tissue surrounding the renal pelvis. Access to the renal pelvis may be via the urinary tract or via minimally invasive incisions through the abdomen and kidney tissue. Treatment is effected by exchanging energy, typically delivering heat or extracting heat through a wall of the renal pelvis, or by delivering active substances.
Perkiomaki J.,University of Oulu |
Ukkola O.,University of Oulu |
Kiviniemi A.,Verve Medical |
Tulppo M.,Verve Medical |
And 4 more authors.
Journal of Cardiovascular Electrophysiology | Year: 2014
Heart Rate Variability and Atrial Fibrillation Background Autonomic nervous system modifies atrial electrophysiologic properties and arrhythmia vulnerability. Methods Heart rate (HR) variability, an indicator of cardiac autonomic regulation, was measured in 784 subjects (mean age 51 ± 6 years; 54% males) from a standardized 45-minute period in a study population (n = 1,045), which consisted of randomly selected hypertensive and age- and sex-matched control subjects at the time of recruitment in 1991-1992 (the OPERA study). Results During a mean follow-up of 16.5 ± 3.5 years, 76 subjects (9.7%) had developed symptomatic atrial fibrillation (AF), needing hospitalization. HR did not predict the occurrence of AF. Among the various spectral and time-domain HR variability indexes, only the low-frequency (LF) spectral component independently predicted AF. In the Cox regression analysis, the hazard ratio of reduced HR corrected LF (LFccv ≤ 1.59%, optimal cutoff from the ROC curve) in predicting the AF was 3.28 (95% CI: 2.06-5.24; P < 0.001). In the multiple Cox regression model, including LFccv and other predictors of AF, such as age, gender, hypertension, history of coronary artery disease, systolic and diastolic blood pressure, body mass index, β-blocking, angiotensin converting enzyme inhibitor and aspirin medication, left atrial size, left ventricular mass index, and left ventricular size obtained by echocardiography, only LFccv (hazard ratio 2.81; 95% CI: 1.64-4.81; P < 0.001), age (P = 0.006), and systolic blood pressure (P = 0.02) remained as significant predictors of AF. Conclusions Impaired LF oscillation of HR predicts new-onset AF in a middle-aged population emphasizing the important role of autonomic nervous system in the genesis of symptomatic AF. © 2014 Wiley Periodicals, Inc.
Koivikko M.L.,University of Oulu |
Tulppo M.P.,Verve Medical |
Kiviniemi A.M.,Verve Medical |
Kallio M.A.,University of Oulu |
And 4 more authors.
Diabetes Care | Year: 2012
OBJECTIVE - Experimental clamp studies have suggested that hypoglycemia evokes a reduction of cardiac vagal control in patients with type 1 diabetes. However, there are limited data on the influence of spontaneous nocturnal hypoglycemia on cardiac autonomic regulation. RESEARCH DESIGN AND METHODS - Adults with type 1 diabetes (n = 37) underwent continuous glucose monitoring via a subcutaneous sensor as well as recording of R-R interval or electrocardiogram for 3 nights. Heart rate (HR) variability was analyzed during periods of hypoglycemia (glucose <3.5 mmol/L) (minimum length of 20 min) and a control nonhypoglycemic period (glucose >3.9 mmol/L) of equal duration and at the same time of night. RESULTS - The duration of hypoglycemic and control episodes (n = 18) ranged from 20 to 190 min (mean 71 min). HR (62 ± 7 vs. 63 ± 9 beats per min; P = 0.30) or the high-frequency component of HR power spectrum (2,002 ± 1,965 vs. 1,336 ± 1,506 ms 2; P = 0.26) did not change during hypoglycemia. Hypoglycemia resulted in a significant decrease in the low-frequency component of HR variability (2,134 6 1,635 vs. 1,169 6 1,029 ms 2, respectively; P = 0.006). The decline in the glucose concentration displayed a significant positive correlation with the decrease of the low-frequency component of HR variability (r = 0.48; P = 0.04). The latter was closely related to an increase in muscle sympathetic nerve activity recorded in 10 subjects during controlled sympathetic activation. CONCLUSIONS - Spontaneous nocturnal hypoglycemia in patients with type 1 diabetes results in a reduction of the low-frequency component of HR, which is best explained by excessive sympathetic activation without a concomitant withdrawal of vagal outflow. © 2012 by the American Diabetes Association.
Verve Medical | Date: 2015-02-06
Apparatus, systems, and methods provide access to the renal pelvis of a kidney to treat renal nerves embedded in tissue surrounding the renal pelvis. Access to the renal pelvis may be via the urinary tract or via minimally invasive incisions through the abdomen and kidney tissue. Treatment is effected by exchanging energy, typically delivering heat or extracting heat through a wall of the renal pelvis, or by delivering active substances to ablate a thin layer of tissue lining at least a portion of the renal pelvis to disrupt renal nerves within the tissue lining of the renal pelvis.