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Renal nerve stimulation (RNS) can result in substantial blood pressure (BP) elevation, and the change was significantly blunted when repeated stimulation after ablation. However, whether RNS could provide a meaningful renal nerve mapping for identification of optimal ablation targets in renal denervation (RDN) is not fully clear. Here, we compared the antihypertensive effects of selective RDN guided by two different BP responses to RNS and explored the nerve innervations at these sites in Kunming dogs. Our data indicated that ablation at strong-response sites showed a more systolic BP-lowering effect than at weak-response sites ( P =0.002), as well as lower levels of tyrosine hydroxylase and norepinephrine in kidney and a greater reduction in plasma norepinephrine ( P =0.004 for tyrosine hydroxylase, P =0.002 for both renal and plasma norepinephrine). Strong-response sites showed a greater total area and mean number of renal nerves than weak-response sites ( P =0.012 for total area and P R =0.649; P =0.012 and R =0.643; P =0.013). Changes of plasma norepinephrine and renal norepinephrine levels at 4 weeks were also correlated with systolic BP changes at 4 weeks ( R =0.837, P R =0.927, P

BACKGROUND Previous studies showed that radiofrequency energy delivery of the renal artery could induce an immediate and substantial blood pressure (BP)-elevation response, which might be indicative of the increase in central sympathetic nervous activity. OBJECTIVE The current study was to investigate whether the presence of BP-elevation response to radiofrequency energy delivery can serve as a surrogate to predict BP reduction following renal artery sympathetic denervation (RDN). METHOD Data were collected on 67 patients undergoing RDN for drug-resistant hypertension. The BP-elevation response to radiofrequency application was defined as elevation of SBP by at least 10 mmHg during radiofrequency energy delivery. The extent of BP reduction at 1, 3, 6, 12 months after RDN were analyzed. Multivariable linear regression analysis of baseline and procedural characteristics was performed to identify the determinants of BP reduction after RDN. RESULTS Ten patients (14.9%) were classified as nonresponders to radiofrequency delivery and showed significantly lower BP reduction compared with responders. The SBP reductions of radiofrequency delivery responders vs. nonresponders were 31.2 ± 8.6 vs. 11.4 ± 8.6 mmHg, 36.3 ± 10.0 vs. 14.6 ± 10.6 mmHg, 39.9 ± 9.9 vs. 15.2 ± 8.8 mmHg, and 40.0 ± 8.7/13.5 ± 5.8 mmHg (P

It is controversial whether angiotensin II receptor blockers provide better protection than calcium antagonists against atrial fibrillation (AF) recurrence in hypertensive patients. This study was designed to compare the effect of nifedipine- and telmisartan-based antihypertensive treatments for preventing AF recurrence in hypertensive patients with paroxysmal AF. A total of 149 hypertensive patients with paroxysmal AF were randomized to nifedipine- or telmisartan-based antihypertensive treatment groups. The target blood pressure (BP) was P =0.742), and Kaplan–Meier analysis showed no significant difference in the freedom from AF recurrence (log-rank test; P =0.48). However, the rate of developing persistent AF in telmisartan group was lower than that in nifedipine group (5.4% versus 16.0%; P =0.035). Patients in telmisartan group had lower values of left atrial diameter, left atrial volume index, and left ventricular mass index at the end of follow-up. The effects of telmisartan in preventing AF recurrences in hypertensive patients with paroxysmal AF after intensive lowering BP is similar to that of nifedipine, but telmisartan has more potent effects on preventing progression to persistent AF.

Background— Electric stimulation has been proved to be available to monitor the efficacy of renal denervation (RDN). This study was to evaluate the effectiveness of high-frequency stimulation (HFS)–guided proximal RDN. Methods and Results— A total of 13 Chinese Kunming dogs were included and allocated to proximal RDN group (n=8) and control group (n=5). HFS (20 Hz, 8 V, pulse width 2 ms) was performed from proximal to distal renal artery in all dogs. Radiofrequency ablations were delivered in proximal RDN group and only at the proximal positive sites where systolic blood pressure (BP) increased ≥10 mm Hg during HFS. Postablation HFS was performed over the previously stimulated sites. BP, heart rate, and plasma norepinephrine were analyzed. In 8 denervated dogs, preablation HFS caused significant BP increases of 6.0±5.0/3.4±5.5, 16.9±11.7/11.1±8.5, and 17.1±8.4/8.5±5.3 mm Hg during the first, second, and third 20 s of HFS at the proximal positive sites. After ablation, these sites showed a negative response to postablation HFS with increases of BP by 1.3±3.0/1.0±2.5, 0.8±3.9/1.5±3.4, and 1.5±4.5/0.7±3.8 mm Hg. Of note, no radiofrequency applications were delivered at the positive sites of middle renal artery, repeated HFS increased BP only by 3.3±5.3/2.8±4.2, 5.3±6.6/3.8±4.7, and 2.9±4.6/1.3±3.2 mm Hg, failed to reproduce the previous BP increases of 6.2±5.6/5.3±4.4, 15.0±9.3/10.2±6.2, and 14.9±7.7/8.4±4.7 mm Hg. At 3 months, BP and plasma norepinephrine substantially decreased in proximal RDN group. Whereas controls showed minimal BP decreases and had similar plasma norepinephrine concentrations as baseline. Conclusions— Renal afferent nerves can be mapped safely, and HFS-guided targeted proximal RDN can achieve apparent BP reduction and sympathetic inhibition.

Background: The study was to evaluate the value of CHADS2 and CHADS2VASC scores on predicting left atrial (LA) thrombus in the patients with atrial fibrillation (AF). Methods and Results: All the non-valvular AF patients undergoing AF ablation from June 2010 to June 2012 were included and divided into two groups: patients without anticoagulation and with Coumadin anticoagulation for at least 4 weeks. The relationship between CHADS2 and CHADS2VASC scores and LA thrombus as identified on transesophageal echocardiography (TEE) was analyzed prior to ablation. A total of 397 patients underwent pre-ablation TEE: 212 patients without anticoagulation, and 185 with anticoagulation. There were no differences in the CHADS2 and CHADS2VASC scores in the two groups. LA thrombus was present in 15.6% and 5.9% for the patients without anticoagulation and for those with anticoagulation, respectively (p = 0.002). There was a strong association between CHADS2 and LA thrombus, and between CHADS2VASC and LA thrombus in the two groups. No thrombus was identified in patients with CHADS2VASC score of 0 in both groups. However, thrombus was detected in 3.5% of patients with CHADS2 score of 0 in the group without anticoagulation, while no thrombus was present in the ones with anticoagulation. CHADS2VASC score of ≥1 (r=2.03, p = 0.04) was the only factor independently associated with LA thrombus in patients without anticoagulation, while both CHADS2VASC score of ≥2 (r=2.61, p=0.02) and CHADS2 score of ≥2 (r=2.73, p=0.01) were independently associated with LA thrombus. Further analyses showed that CHADS2VASC score was a better predictor for LA thrombus than CHADS2 score in patients without anticoagulation. However, there was no difference between the two scoring systems in predicting LA thrombus in patients with anticoagulation. Conclusions: LA thrombus was associated with CHADS2VASC and CHADS2 scores in non-valvular AF patients without anticoagulation. CHADS2VASC score was a better predictor than CHADS2 score for LA thrombus in patients without anticoagulation. The data suggested that it might be unnecessary to undergo a TEE evaluation for LA thrombus in low risk patients identified by CHADS2VASC score regardless anticoagulation therapy prior to cardioversion or ablation.