The Impact of Haemodialysis on the Outcomes of Catheter Ablation in Patients With Paroxysmal Atrial Fibrillation.

The impact of haemodialysis on the outcomes of catheter ablation in patients with paroxysmal atrial fibrillation.

Europace. 2013 Aug 4;
Takigawa M, Kuwahara T, Takahashi A, Kobori A, Takahashi Y, Okubo K, Watari Y, Sugiyama T, Kimura S, Takagi K, Hikita H, Hirao K, Isobe M

The outcomes of catheter ablation (CA) in patients with paroxysmal atrial fibrillation (PAF) who are undergoing haemodialysis (HD) have not been fully elucidated. This study aimed to determine the impact of HD on CA outcome in these patients.METHODS AND RESULTS: We examined 1364 consecutive PAF patients (mean age, 61 ± 10 years) who underwent CA, including 32 (2.3%) patients undergoing HD. The patients undergoing HD had a significantly lower body mass index (P < 0.0001), higher CHADS2 score (P = 0.006), and higher prevalence of structural heart disease (P < 0.0001), hypertension (P = 0.002), and congestive heart failure (P = 0.02). Echocardiography indicated a larger left atrial diameter (P < 0.0001) and left ventricular diameter (P = 0.0002) in the HD patients. Haemodialysis was a significant predictor of AF recurrence (hazard ratio 2.56; 95% confidence interval 1.56-4.03; P = 0.0004) in the overall population. Sinus rhythm maintenance rates in the HD patients at 1, 3, and 5 years were 42.3, 37.6, and 19.7%, respectively, after the first procedure, and 64.7, 54.9, and 47.1%, respectively, after the final procedure (median, 2; range, 1-2 procedures); these rates were significantly lower than those in the non-HD patients (P < 0.0001). The 5-year survival rate was 78.1% in the HD patients.CONCLUSION: Haemodialysis was significantly associated with AF recurrence after CA for PAF. However, an ?50% success rate for sinus rhythm maintenance without antiarrhythmic drug therapy in HD patients suggested that CA could be an option for the treatment of AF. HubMed – drug

The time course of exit and entrance block during cryoballoon pulmonary vein isolation.

Europace. 2013 Aug 4;
Andrade J, Khairy P, Dubuc M, Deyell MW, Roy D, Talajic M, Thibault B, Guerra PG, Rivard L, Macle L

The dynamic time course of entrance and exit block during pulmonary vein isolation (PVI) is unknown. The purpose of this series was to dynamically evaluate the manifestation of entrance and exit conduction block during simultaneous circumferential PVI.METHODS AND RESULTS: Pacing manoeuvres were performed during cryoballoon ablation of left-sided pulmonary veins (PVs) in 30 consecutive patients with a history of drug-refractory paroxysmal atrial fibrillation. At the onset of ablation continuous pacing was performed from the PV at a cycle length of 600 ms until the appearance of exit block. Once exit block was demonstrated, uninterrupted pacing was immediately transitioned to the distal coronary sinus (CS) catheter and continued at 600 ms throughout the rest of the cryoapplication. The timing of exit block, entrance block, and corresponding cryoballoon temperature were noted for all patients. In the 45 PVs when real-time PV recordings were available during cryothermal ablation, the presence of exit block was reliably demonstrated to precede entrance block (P < 0.0001) by a median of 5 s [interquartile range (IQR) 3, 12; median temperature at isolation -39°C (IQR -30, -45); nadir ablation temperature -53°C (IQR -48, -59)]. In all cases, when uninterrupted pacing was transitioned from the PV to the distal CS, entrance conduction from the left atrium to PV remained intact.CONCLUSION: Circumferential PV ablation results in progressive PVI, beginning with unidirectional exit block, and followed by entrance block. As exit block reliably precedes entrance block, we are able to provide justification for the exclusive use of entrance conduction block as the endpoint of cryoballoon-based PVI. HubMed – drug

Exposure to cocaine regulates inhibitory synaptic transmission from the ventral tegmental area to nucleus accumbens.

J Physiol. 2013 Aug 5;
Ishikawa M, Otaka M, Neumann P, Wang Z, Cook J, Schlueter O, Dong Y, Huang Y

Synaptic projections from the ventral tegmental area (VTA) to the nucleus accumbens (NAc) make up the backbone of the brain reward pathway, a neural circuit that mediates behavioral responses elicited by natural rewards as well as by cocaine and other drugs of abuse. In addition to the well-known modulatory dopaminergic projection, the VTA also provides fast excitatory and inhibitory synaptic input to the NAc, directly regulating NAc medium spiny neurons (MSNs). However, the cellular nature of VTA-to-NAc fast synaptic transmission and its roles in drug-induced adaptations are not well understood. Using viral-mediated in vivo expression of channelrhodopsin 2, the present study dissected fast excitatory and inhibitory synaptic transmission from the VTA to NAc MSNs in rats. Our results suggest that following repeated exposure to cocaine (15 mg/kg/d x 5 d, i.p., 1 or 21 d withdrawal), a presynaptic enhancement of excitatory transmission and suppression of inhibitory transmission occurred at different withdrawal time point at VTA-to-NAc core synapses. In contrast, no postsynaptic alterations were detected at either type of synapses. These results suggest that changes in VTA-to-NAc fast excitatory and inhibitory synaptic transmissions may contribute to cocaine-induced alteration of the brain reward circuitry. HubMed – drug

Change of obstruction level during drug-induced sleep endoscopy (DISE) according to sedation depth in obstructive sleep apnea.

Laryngoscope. 2013 Aug 5;
Hong SD, Dhong HJ, Kim HY, Sohn JH, Jung YG, Chung SK, Park JY, Kim JK

We evaluated the change in upper airway collapse according to the depth of sedation during drug-induced sleep endoscopy (DISE), as well as characteristics possibly associated with that change.Prospective, single center, observational study.Twenty-nine patients with upper airway collapse were twice evaluated using DISE according to the depth of sedation, as confirmed by the bispectral index (BIS), which is a measure of the level of consciousness. Changes in the site and degree of obstruction according to the change in sedation depth at the retropalatal and the retroglossal levels were evaluated. The possible contributing factors of this change were explored.As DISE sedation deepened, the upper airway became narrower in 37% of patients at the retropalatal level and in 44.8% of patients at the retroglossal level. No clinical, polysomnographic, or cephalometric variables showed any association with the change in the degree of retroglossal airway narrowing, with the exception of mouth breathing during DISE.The degree of upper airway narrowing can be aggravated according to the sedation depth. The monitoring of sedation depth during DISE is critical, especially in patients with mouth breathing.4. Laryngoscope, 2013. HubMed – drug

No More Shame: The Treatment Center
In the 2011 National Survey on Drug Use and Health, it was found that an estimated 21.6 million people were classified as needing treatment for the abuse of …