Coexistence of atrioventricular accessory pathways and drug-induced type 1 Brugada pattern.

BACKGROUND: Atrial arrhythmias, particularly atrioventricular nodal reentrant tachycardia, can coexist with drug-induced type 1 Brugada electrocardiogram (ECG) pattern (DI-Type1-BrP). The present study was designed to determine the prevalence of DI-Type1-BrP in patients with atrioventricular accessory pathways (AV-APs) and to investigate the clinical, electrocardiographic, electrophysiologic, and genetic characteristics of these patients. METHODS: One-hundred twenty-four consecutive cases of AV-APs and 84 controls underwent an ajmaline challenge test to unmask DI-Type1-BrP. Genetic screening and analysis was performed in 55 of the cases (19 with and 36 without DI-Type1-BrP). RESULTS: Patients with AV-APs were significantly more likely than controls to have a Type1-BrP unmasked (16.1 vs 4.8%, P = 0.012). At baseline, patients with DI-Type1-BrP had higher prevalence of chest pain, QR/rSr' pattern in V1 and QRS notching/slurring in V2 and aVL during preexcitation, rSr' pattern in V1 -V2 , and QRS notching/slurring in aVL during orthodromic atrioventricular reentrant tachycardia (AVRT) compared to patients without DI-Type1-BrP. Abnormal QRS configuration (QRS notching/slurring and/or fragmentation) in V2 during preexcitation was present in all patients with DI-Type1 BrP. The prevalence of spontaneous preexcited atrial fibrillation (AF) and history of AF were similar (15% vs 18.3%, P = 0.726) in patients with and without DI-Type1-BrP, respectively. The prevalence of mutations in Brugada-susceptibility genes was higher (36.8% vs 8.3%, P = 0.02) in patients with DI-Type1-BrP compared to patients without DI-Type1-BrP. CONCLUSIONS: DI-Type1-BrP is relatively common in patients with AV-APs. We identify 12-lead ECG characteristics during preexcitation and orthodromic AVRT that point to an underlying type1-BrP, portending an increased probability for development of malignant arrhythmias.

Disappearance of Idiopathic Outflow Tract Premature Ventricular Contractions After Catheter Ablation of Overt Accessory Pathways.

BACKGROUND: Multiple mechanisms have been proposed for idiopathic premature ventricular contractions (PVCs) originating from the outflow tracts (OTs). Recent observations such as the coexistence of these arrhythmias with atrioventricular nodal reentrant tachycardias and the association between discrete prepotentials and successful ablation sites of ventricular arrhythmias (VAs) from the OTs suggest a common link. OBJECTIVE: In this case series we draw attention to a unique association between accessory pathways (APs) and idiopathic PVCs from the OTs, disappearing after AP ablation. METHODS: We identified 6 cases in collaboration with several international electrophysiology centers, which presented with pre-excitation in association with OT, and in 1 case inflow tract (IT), PVCs on 12-lead surface ECG. RESULTS: Six cases displayed pre-excitation and PVCs, in 5 cases originating from the right ventricular outflow tract (RVOT) and in 1 case from the right ventricular inflow tract (RVIT). In all patients, PVCs were monomorphic and had fixed coupling intervals, in 3 cases presenting in bigeminy. Catheter ablation of the AP led to the simultaneous disappearance of PVCs in 5 of 6 cases. The sites of ablation were remote from the OTs in all these cases. In most cases, the occurrence of OT PVCs was closely associated with the presence of pre-excitation. CONCLUSION: The coexistence of pre-excitation and PVCs from the OTs and the fact that in 5 of 6 cases PVCs disappeared after AP ablation suggests a common mechanism for arrhythmia genesis.

Isolation of persistent left superior vena cava during atrial fibrillation ablation.

Persistent left superior vena cava is a rarely seen anomaly but it may be an arrhythmogenic source for paroxysmal atrial fibrillation. Furthermore, the complex anatomicregion between the left superior vena cava and the pulmonary veins may leads to misinterpretation of the pulmonary vein recordings during atrial fibrillation ablation. Approaches that might be helpful to overcome these problems are discussed in this case report.

A simple method for radiation exposure reduction during atrial fibrillation ablation: the lead-apron-free approach.

BACKGROUND: Radiofrequency catheter ablation (RFCA) is a well-established treatment for atrial fibrillation (AF). Fluoroscopy, a widely used imaging method for RFCA, has significant implications for human health. Although no fluoroscopy or near-zero fluoroscopy strategies have gained popularity, they have limitations, such as long procedure times, additional equipment, and expertise. A simple and cost-effective radiation reduction method is needed for treating AF and is compatible with the daily workflow. We aimed to compare the efficacy and safety of fluoroscopy-free and lead apron-free (LAF) after transseptal puncture AF ablation with conventional ablation (CON). METHODS: This retrospective study included all patients who underwent RF catheter AF ablation. The lead apron used for protection was removed immediately before 3D reconstruction of the left atrium (LA) after transseptal puncture (TSP), while fluoroscopy was performed on stand-by and locked-in. The pulmonary vein isolation (PVI) was performed using a 3D mapping system, a multielectrode catheter, and a Smart Touch contact force (CF) sensing catheter, via the lead-apron-free (LAF) method, which is similar to the conventional ablation (CON) method. RESULTS: This study enrolled 152 consecutive patients, with 72 and 80 patients in the LAF and CON groups, respectively. The LAF group demonstrated significantly lower values in total fluoroscopy time (6.9 vs. 14 min, P<0.001) and dose area product (DAP) values (15.4±12.1 vs. 31.5±17.4 G/m2, P<0.001) than the CON group. However, there was no significant difference in the total procedure time (83.6±21.1 vs. 77.2±11.4 min, P=0.12) between the two groups. Only four procedures (5.5%) required repositioning of the apron, and no complications were observed with the LAF method. Pulmonary vein isolation was achieved in all patients. CONCLUSIONS: The LAF method reduced fluoroscopy use compared with CON, with no change in procedure time or efficacy.

Aortic stiffness and flow-mediated dilatation in normotensive offspring of parents with hypertension.

OBJECTIVES: Although hypertension has been shown to be one of the most important risk factors for atherosclerosis, data about the presence of subclinical atherosclerosis in normotensive offspring with parental history of hypertension are scarce. Accordingly, the current study was designated to evaluate flow-mediated dilatation and aortic stiffness, which are early signs of atherosclerosis in young subjects with parental history of hypertension. METHODS: A total of 140 [corrected] healthy, non-obese subjects in the age group of 18-22 years were included in this study and divided into two groups. The first group included 70 offspring of hypertensive parents and the second group included 70 offspring of normotensive parents as controls. In all subjects, endothelium-dependent and endothelium-independent vasodilatation of the brachial artery and aortic elastic parameters were investigated using high-resolution Doppler echocardiography. RESULTS: Offspring of hypertensive parents demonstrated higher values of aortic stiffness (7.1 plus or minus 1.88 and 6.42 plus or minus 1.56, respectively) but lower distensibility (9.47 plus or minus 1.33 and 11.8 plus or minus 3.36 square centimetres per dyne per 106) and flow-mediated dilatation (4.57 plus or minus 1.3 versus 6.34 plus or minus 0.83 percent, p equals 0.0001, respectively) than offspring of hypertensive parents. CONCLUSION: We observed blunted endothelium-dependent dilatation and aortic stiffness in offspring of hypertensive parents compared with offspring of normotensive [corrected] parents. This is evident in the absence of overt hypertension and other diseases, suggesting that parental history of hypertension is a risk for subclinical atherosclerosis and it may contribute to the progression to hypertension and overt atherosclerosis in later life.

Correction to: Impaired coronary blood flow may be related to elevated homocysteine levels in patients with metabolic syndrome.

Correction to: Wien Klin Wochenschr 2015 https://doi.org/10.1007/s00508-015-0854-z The original version of this article unfortunately contained a mistake. The first names of Dr. Ismail Dogu Kilic were interchanged.

Sodium bicarbonate, N-acetylcysteine, and saline for prevention of radiocontrast-induced nephropathy. A comparison of 3 regimens for protecting contrast-induced nephropathy in patients undergoing coronary procedures. A single-center prospective controlled trial.

BACKGROUND: Several protective therapies have been developed to prevent contrast-induced nephropathy (CIN). We aimed to investigate the efficacy of sodium bicarbonate by comparing 2 other regimens, including combination of N-acetylcysteine (NAC) plus sodium chloride and sodium chloride alone, to prevent CIN in patients undergoing cardiovascular procedures. METHODS: We prospectively enrolled 264 patients who were scheduled for cardiovascular procedures and had a baseline creatinine level >1.2 mg/dL. The patients were assigned 1 of 3 prophylactic regimens: infusion of sodium bicarbonate, sodium chloride, sodium chloride plus oral NAC (600 mg bid). Contrast-induced nephropathy was defined as an increase in serum creatinine level >25% or 0.5 mg/dL after 48 hours. RESULTS: There were no significant differences among groups regarding baseline demographic properties and nephropathy risk factors. The change in creatinine clearance was significantly better in the sodium bicarbonate group than other 2 groups (P = .007). The incidence of CIN was significantly lower in the sodium bicarbonate group (4.5%) compared with sodium chloride alone (13.6%, P = .036) and tended to be lower than in the combination group (12.5%, P = .059). After adjusting the Mehran nephropathy risk score, the risk of CIN significantly reduced with sodium bicarbonate compared with sodium chloride alone (adjusted risk ratio 0.29, P = .043). CONCLUSIONS: Hydration with sodium bicarbonate provides better protection against CIN than the sodium chloride infusion does alone. Combination therapy of NAC plus sodium chloride did not offer additional benefit over hydration with sodium chloride alone.

Impaired coronary blood flow may be related to elevated homocysteine levels in patients with metabolic syndrome.

BACKGROUND: Metabolic syndrome (MS) refers to a group of cardiovascular risk factors associated with endothelial dysfunction and impaired coronary blood flow (CBF). Homocysteine (Hcy) is another risk factor for the development of insulin resistance and endothelial dysfunction. However, the relationship between Hcy levels and CBF in patients with MS has not been investigated specifically. In the present study, we aimed to evaluate the relationship between Hcy levels and CBF in MS patients with normal coronary arteries. METHODS: The study population included 36 patients with MS (20 males, 16 females; mean age = 55 ± 9 years) and 36 control subjects (20 males, 16 females; mean age = 51 ± 7 years). All subjects had angiographically proven normal coronary arteries. Plasma Hcy concentrations were evaluated after a fast of 12 h or longer. The CBF rates of all subjects were documented by the thrombolysis in myocardial infarction (TIMI) frame count method. RESULTS: The TIMI frame counts for each major epicardial coronary artery and mean TIMI frame count were found to be significantly higher in the MS group compared with the control group (left anterior descending coronary artery (LAD): 53 ± 26 vs. 39 ± 17; p = 0.01, left circumflex artery (LCx): 32 ± 12 vs. 26 ± 11; p = 0.01, right coronary artery (RCA): 33 ± 14 vs. 26 ± 12; p = 0.02, mean TIMI frame count: 39 ± 16 vs. 20 ± 12; p = 0.01). Plasma Hcy levels in patients with MS were significantly higher compared with controls (MS group = 11.6 ± 4 and control group = 9.6 ± 2.6; p = 0.01). Additionally, plasma Hcy levels were positively correlated with each calculated TIMI frame count value in the MS group (LAD, r: 0.28 and p = 0.006; LCx, r: 0.25 and p = 0.022; RCA, r: 0.26 and p = 0.042; mean TIMI frame count, r: 0.28 and p = 0.004). CONCLUSION: Plasma Hcy levels and TIMI frame counts were significantly higher in patients with MS. Impaired CBF in MS may be related to elevated levels of Hcy, even if Hcy levels are normal.

Successful ablation of atrioventricular nodal re-entrant tachycardia in a patient with interruption of inferior vena cava and azygos continuation.

Congenital anomalies of the venous system are a challenge for cardiac catheterization and radiofrequency ablation. This article describes ablation of atrioventricular nodal re-entrant tachycardia performed solely through the azygos continuation in a patient with inferior vena cava interruption.