Prognostic dilemmas for SIDS in idiopathic fetal right atrium dilatation: Case report and review literature.

The authors describe a case of fetal isolated right atrial enlargement or IDRA (idiopathic dilatations of the right atrium) evident in third trimester, complicated by arrhythmia in the female infant during the 1° month of life with ECG diagnosis of Wolf-Parkinson-White syndrome (WPW). The eldest sister died at 6 years because of an arrhythmia with the same diagnosis of WPW. The review of the literature on IDRA frequently shows a familial genetic aggregation. The pathogenetic mechanism underlying the dilation of the right atrium could consist of a myopathy or electrical conduction disorder. The exclusive involvement of the right atrium may be due to the increased pressure in the fetal right atrium. On the basis of our case and after review of the literature, we must be careful in defining as physiological the enlargement of the right fetal atrium in the third trimester of pregnancy. The ultrasound sign of IDRA may be a fetal prodrome of SIDS (sudden infant death syndrome).

The role of microbiota in the management of genitourinary syndrome of menopause.

It is estimated that the 25-50% of women who are reaching menopause every year report symptoms related to the genitourinary syndrome of menopause (GSM). The symptoms are not due simply to lack of estrogen. One possible contributing cause of symptoms is the vaginal microbiota. The vaginal microbiota is a dynamic entity and plays a critical role in the pathogenic interplay of postmenopausal changes. Treatment of this syndrome depends on the severity and type of the symptoms and on the preferences and expectations of women. As there are many treatment options, therapy should be individualized. While new evidence on the role of Lactobacilli in premenopause is emerging, the role of Lactobacilli is still unclear in GSM and the impact of microbiota on vaginal health remains conflictual. However, some reports show promising data on the effect of probiotic therapy in menopause. In the literature there are few studies and small population samples on the role of an exclusive therapy with Lactobacilli and further data will be mandatory. Studies involving large numbers of patients and different intervention periods will be necessary to obtain evidence of the preventive and curative role of vaginal probiotics.

Lactobacillus plantarum P17630 for preventing Candida vaginitis recurrence: a retrospective comparative study.

BACKGROUND: Recurrence is a frequent complaint of patients with vulvovaginal candidiasis (VVC). Although the pathogenesis of VVC remains a controversial issue, disruption of the balance between the vaginal microbiota may facilitate overgrowth by Candida. Some probiotic bacterial strains can suppress Candida albicans; Lactobacillus plantarum P17630 is able to attach to vaginal epithelial cells and significantly reduce the adhesion of C. albicans. OBJECTIVE: To evaluate the effect of the application of Lactobacillus plantarum P17630 in restoring the vaginal microbiota and prevention of relapses among women with acute VVC undergoing conventional (azole) local and main therapy. METHODS: Retrospective comparative study. We recruited 89 women with a diagnosis of VVC, who were placed into two groups on the basis of reported treatment. The control group was treated with a daily dose of 2% clotrimazole vaginal cream at bedtime for 3 days, followed by vaginal application of a capsule containing lubricant once a day for 6 days and then once a week for another 4 weeks. The probiotic group was treated with the same azole-based protocol but followed by vaginal application of a capsule containing Lactobacillus plantarum P17630 (>108 CFU) once a day for 6 days and then once a week for another 4 weeks beginning the day following clotrimazole discontinuation. Clinical and diagnostic patterns were monitored for three months of follow-up. RESULTS: At the end of study the probiotic-treated women showed a statistically significant increase in Lactobacillus values "+++" (80% versus 40%, p<0.001) and a better subjective resolution of symptoms such as vaginal discomfort described as burning or itching (90% versus 67.5%, p<0.03). Among controls there was a non-significant increase at 3 months of recurrence of infection, but a significant increase of women with value of pH=5 or >5. CONCLUSION: Although the results of different studies are controversial, most have suggested use of probiotics in the prevention or treatment of VVC, and no adverse effects have been reported. Our data with L. plantarum P17630 (Gyno-Canesflor - Bayer) confirm the role of this specific strain as a potential empirical preventive agent for reducing vaginal discomfort after conventional treatment of acute VVC and shifting the vaginal milieu toward a predominance of lactobacilli with an improvement of the vaginal pH value.

Congenital Frey's syndrome associated with nontraumatic bilateral trifid mandibular condyle.

Congenital Frey's syndrome and bilateral trifid mandibular condyle are two different entities. The occurrence of both together is rare and has not been reported in the literature. This article describes the case of a 17-year-old male patient who complained of bilateral warmness, flushing and sweating in the preauricular area after eating spicy and sour foods since childhood. He had no complaint related to the functions of the temporomandibular joint and had no history of facial trauma. The patient was treated with injections of botulinum toxin A and the signs and symptoms of Frey's syndrome improved significantly.

Pelvic inflammatory disease (PID) from Chlamydia trachomatis versus PID from Neisseria gonorrhea: from clinical suspicion to therapy.

Pelvic inflammatory disease (PID) is the most significant complication of sexually transmitted infections in childbearing-age women and it represents an important public health problem because of its long-term sequelae (chronic pelvic pain, tubal infertility, ectopic pregnancy). Prior to the mid 1970s PID was considered a monoetiologic infection, due primarily to Neisseria gonorrhea. Now it is well documented as a polymicrobial process, with a great number of microrganisms involved. In addition to Neisseria gonorrhea and Chlamydia trachomatis, other vaginal microrganisms (anaerobes, Gardnerella vaginalis, Haemophilus influenzae, enteric Gram negative rods, Streptococco agalactie, Mycoplasma genitalium) also have been associated with PID. There is a wide variation in PID clinical features; the type and severity of symptoms vary by microbiologic etiology. Women who have chlamydial PID seem more likely than women who have gonococcal PID to be asymptomatic. Since clinical diagnosis is imprecise, the suspicion of PID should be confirmed by genital assessment for signs of inflammation or infection, blood test and imaging evaluation. Laparoscopic approach is considered the gold standard. According to the polymicrobial etiology of PID, antibiotic treatment must provide broad spectrum coverage of likely pathogens. Early administration of antibiotics is necessary to reduce the risk of long-term sequelae.

Very high frequency of the polymorphism for the insulin receptor substrate 1 (IRS-1) at codon 972 (glycine972arginine) in Southern Italian women with polycystic ovary syndrome.

A major component of the polycystic ovary syndrome (PCOS) is the insulin resistance. Only a few studies have evaluated the IRS-1 polymorphism at codon 972, sometimes in the absence of a control group, and with great variability in frequency (0-23% in PCOS vs. 0-17% in controls), and with no unequivocal relationships between the polymorphism and clinical or biochemical indexes. The aim of the work was to evaluate the frequency of the IRS-1 polymorphism at codon 972 in PCOS, and correlate it to clinical and biochemical indexes. We assessed the rs 1801278 polymorphic variant in the IRS-1 gene (Gly972Gly=wild-type; Gly972Arg=heterozygosity; Arg972Arg=homozygosity) in genomic DNA by restriction fragment length polymorphism. The study was conducted at an academic medical center with the participation of 65 women with PCOS and 27 age-matched healthy women (controls). Compared to controls, Gly972Arg was very frequent in PCOS (77% vs. 18%, p<0.0001); one PCOS woman was homozygous. Compared to wild-type PCOS, heterozygous PCOS women had only three significantly different indexes: higher fasting insulin, insulin resistance index, and lower 120 min OGTT glucose. Moreover, in the correlation analysis between any two clinical or biochemical variables, the Pearson's correlation coefficients were frequently of different magnitude in heterozygous PCOS versus wild-type PCOS. Overall, heterozygous PCOS had a greater number of statistically significant relationships between different clinical, metabolic and hormonal indexes: 44 direct and 9 inverse versus 6 and 3, respectively. The IRS-1 Gly972Arg has the highest frequency reported world-wide for PCOS women. This variant is associated with insulin resistance and higher fasting insulin in PCOS women.

High serum resistin in chronic viral hepatitis is not a marker of metabolic disorder.

BACKGROUND/AIMS: The role of resistin, an adipocyte-secreted hormone, in insulin resistance and in inflammation is controversial. In chronic hepatitis C, insulin resistance, type 2 diabetes and liver steatosis are frequent and inconsistently correlated to circulating resistin levels. In this study we assessed if viral aetiology and host metabolic parameters influence serum resistin in patients with HCV- and HBV- related chronic hepatitis. METHODOLOGY: Serum resistin was measured by ELISA and correlated to viral aetiology, age, gender, BMI, HOMA-IR, liver steatosis, hepatitis staging and grading, blood glucose, triglycerides and cholesterol in 43 patients with chronic hepatitis C, in 16 with chronic hepatitis B and in 29 healthy controls. RESULTS: In both groups of patients resistin was significantly higher than in controls, with higher values in HBV- than in HCV-patients (p = 0.0007). Resistin levels were correlated to aetiology and, inversely, to age (p = 0.026), diabetes (p = 0.036) and steatosis (p = 0.029). Multiple regression analysis showed that resistin concentration was dependent only on the aetiology of liver disease (p = 0.001). CONCLUSIONS: In chronic viral hepatitis serum resistin levels are high and not associated with altered metabolic parameters or with the histological activity of the disease. The meaning of higher resistin in HBV- than in HCV- chronic hepatitis is unclear.

Anti-Mullerian hormone (AMH) as a predictive marker in assisted reproductive technology (ART).

BACKGROUND: In women, anti-Müllerian hormone (AMH) levels may represent the ovarian follicular pool and could be a useful marker of ovarian reserve. The clinical application of AMH measurement has been proposed in the prediction of quantitative and qualitative aspects in assisted reproductive technologies (ART). In men AMH is secreted in both the serum and seminal fluid. Its measurement may be useful in clinical evaluation of the infertile male. METHODS: The PubMed database was systematically searched for studies published until the end of January 2009, search criteria relevant to AMH, ovarian reserve, ovarian response to gonadotrophin stimulation, spermatogenesis and azoospermia were used. RESULTS: AMH seems to be a better marker in predicting ovarian response to controlled ovarian stimulation than age of the patient, FSH, estradiol and inhibin B. A similar performance for AMH and antral follicular count has been reported. In clinical practice, AMH measurement may be useful in the prediction of poor response and cycle cancellation and also of hyper-response and ovarian hyperstimulation syndrome. In the male, the wide overlap of AMH values between controls and infertile men precludes this hormone from being a useful marker of spermatogenesis. CONCLUSIONS: As AMH may permit the identification of both the extremes of ovarian stimulation, a possible role for its measurement may be in the individualization of treatment strategies in order to reduce the clinical risk of ART along with optimized treatment burden. It is fundamental to clarify the cost/benefit of its use in ovarian reserve testing. Regarding the role of AMH in the evaluation of infertile men, AMH as single marker of spermatogenesis does not seem to reach a satisfactory clinical utility.

Electromyographic analysis of deltoid muscle fatigue during abduction on scapular and frontal planes.

The aim of the study was to compare the fatigue rates of the deltoid muscle portions in the scapular and frontal planes. Ten healthy men without shoulder muscle impairment took part in the study. They performed isometric arm abduction for 30 seconds against a resistance of load cell while the electromyographic data were collected. The electromyographic data were transformed by the Fast Fourier Transform, to obtain the median power frequency (MDPF). The changes in MDPF of the three deltoid portions in the scapular and frontal planes were compared. The acromialis and spinalis portions fatigued during the exercises. The clavicularis portion presented no fatigue. A statistically significant difference occurred between the clavicularis and the other two portions (P < 0.05). No differences were found when the planes were compared. It represents to practice no preferential order during rehabilitation. Moreover, the acromialis and spinalis portions fatigue, although the clavicularis portion did not fatigue. The actions of other muscles of the shoulder girdle can explain this fact. Moreover, these two portions need more attention to avoid fatigue during exercises. In general, therapeutic strategies for injured patients should not only be directed towards increased force, but also towards fatigue control during shoulder exercises.

Dynamic and dual-site atrial pacing in the prevention of atrial fibrillation: The STimolazione Atrial DInamica Multisito (STADIM) Study.

OBJECTIVES: The impact of new algorithms to consistently pace the atrium on the prevention of atrial fibrillation (AF) remains unclear. Our randomized, crossover study compared the efficacy of single- and dual-site atrial pacing, with versus without dynamic atrial overdrive pacing in preventing AF. METHODS: We studied 72 patients (mean age = 69.6 +/- 6.5 years, 34 men) with sick sinus syndrome (SSS) and paroxysmal or persistent AF, who received dual-chamber pacemakers (PM) equipped with an AF prevention algorithm and two atrial leads placed in the right atrial appendage (RAA), by passive fixation, and in the coronary sinus ostium (CS), by active fixation, respectively. At implant, the patients were randomly assigned to unipolar CS versus RAA pacing. The PM was programmed in DDDR mode 1 month after implant. Each patient underwent four study phases of equal duration: (1) unipolar, single site (CS or RAA) pacing with the AF algorithm ON (atrial lower rate = 0 ppm); (2) unipolar, single site pacing with the AF algorithm OFF (atrial lower rate = 70 bpm); (3) bipolar, dual-site pacing with AF algorithm ON; (4) bipolar, dual-site pacing with the AF algorithm OFF. RESULTS: Among 40 patients (56%), who completed the follow-up (15 +/- 4 months) no difference was observed in the mean number of automatic mode switch (AMS) corrected for the duration of follow-up, in unipolar (5.6 +/- 22.8 vs 2.6 +/- 5.5) or bipolar mode (3.3 +/- 12.7 vs 2.1 +/- 4.9) with, respectively, the algorithm OFF or ON. With the AF prevention algorithm ON, the percentage of atrial pacing increased significantly from 78.7 +/- 22.1% to 92.4 +/- 4.9% (P < 0.001), while the average ventricular heart rate was significantly lower with the algorithm ON (62.4 +/- 17.5 vs 79.9 +/- 3 bpm (P < 0.001). CONCLUSIONS: The AF prevention algorithm increased the percentage of atrial pacing significantly, regardless of the atrial pulse configuration and pacing site, while maintaining a slower ventricular heart rate. It had no impact on the number of AMS in the unipolar and bipolar modes in patients with SSS.

Serum anti-Mullerian hormone throughout the human menstrual cycle.

BACKGROUND: The anti-Mullerian hormone (AMH) is a member of the transforming growth factor (TGF) superfamily. In women, AMH serum levels can be almost undetectable at birth, with a subtle increase noted after puberty. Data are lacking with regard to menstrual cycle day-to-day fluctuations. This longitudinal study was designed to investigate the pattern of secretion of AMH throughout the menstrual cycle in regularly cycling women. METHODS: Twelve healthy female subjects aged 18-24 years participated in this study. Blood samples were taken every other day throughout one menstrual cycle. Serum FSH, LH, estradiol (E(2)), progesterone, inhibin B and AMH levels were assayed by double-antibody radioimmunoassay using commercial kits. RESULTS: Serum AMH in the first days of the menstrual cycle (days -14 to -12) was 3.8 +/- 1.2 ng/ml (mean +/- SD). No significant changes were observed in serum AMH levels throughout the menstrual cycle. The highest value was 3.9 +/- 1.3 ng/ml at day -12 and the lowest value was 3.4 +/- 1.1 ng/ml at day 14, and the difference was not significant. CONCLUSION: In this study, we demonstrated that serum AMH levels do not change significantly throughout the menstrual cycle. Hence, AMH exhibits a relatively stable expression during the menstrual cycle, making it an attractive determinant of ovarian activity.

Response to flecainide infusion predicts long-term success of hybrid pharmacologic and ablation therapy in patients with atrial fibrillation.

OBJECTIVES: We tested the hypothesis that the response to flecainide infusion can identify patients with atrial fibrillation (AF) in whom the hybrid pharmacologic and ablation therapy reduces the recurrences of AF. BACKGROUND: Infusion of class IC anti-arrhythmic drugs may promote transformation of AF into atrial flutter. Catheter ablation of atrial flutter has been demonstrated to be highly effective in preventing recurrences of atrial flutter. METHODS: Seventy-one consecutive patients with paroxysmal or chronic AF, in whom flecainide infusion (2 mg/kg body weight, intravenously) determined the transformation of AF into common atrial flutter (positive response), were randomized to receive one of the following treatments: oral pharmacologic treatment with flecainide (group A, n = 23); the hybrid treatment (catheter ablation of the inferior vena cava-tricuspid annulus isthmus, plus oral flecainide) (group B, n = 24); or catheter ablation of the isthmus only (group C, n = 24). Thirty-seven patients with a negative response to flecainide, who chose to be submitted to the hybrid treatment, were selected as the control group (group D). RESULTS: During a mean follow-up period of 24 +/- 7.2 months, the recurrences of AF and atrial flutter in group B (42%) were significantly lower than those in group A (78%, p < 0.001), group C (92%, p < 0.001) and group D (92%, p < 0.001). CONCLUSIONS: The creation of a complete bi-directional conduction block at the inferior vena cava-tricuspid annulus isthmus, plus flecainide administration, reduces the recurrences of both AF and atrial flutter in patients with class IC atrial flutter. Moreover, the early response to flecainide is safe and reliable in identifying patients who may benefit from this therapy.

Pretreatment with verapamil in patients with persistent or chronic atrial fibrillation who underwent electrical cardioversion.

OBJECTIVES: To evaluate, in a prospective and randomized fashion, the efficacy of a pretreatment with verapamil (V) in reducing recurrences of atrial fibrillation (AF) after electrical cardioversion (C). BACKGROUND: The increased vulnerability for AF recurrence is probably due to AF-induced changes in the electrophysiologic properties of the atria. This electrical remodeling seems to be due to intracellular calcium overload. METHODS: One hundred seven patients with persistent or chronic AF underwent external and/or internal C. All patients received oral propafenone (P) (900 mg/day) three days before and during the entire period of follow-up (three months). In the first group, patients received only the P. In the second group, in adjunct to P, oral V (240 mg/day) was initiated three days before C and continued during the follow-up. Finally, in the third group, oral V was administered three days before and continued only for three days after electrical C. RESULTS: During the three months of follow-up, 23 patients (23.7%) had AF recurrence. Mantel-Haenszel cumulative chi-square reached a significant level only when comparing AF free survival curves of group I versus group II and group III (chi-square = 5.2 and 4, respectively; p < 0.05). Significantly, 15 (65.2%) AF relapses occurred during the first week after cardioversion with a higher incidence in group I (10/33 patients, 30.3%) than group II (2/34 patients, 5.9%; p = 0.01) and group III (3/30 patients, 10%; p = 0.04). CONCLUSIONS: Six days of oral V administration centered on the C day, combined with P, significantly reduce the incidence of early recurrences of AF compared with P alone.

[The predictive value of junctional beats during the radiofrequency transcatheter ablation of the slow pathway of the nodal reentry circuit]. / Valore predittivo dei battiti giunzionali durante l'ablazione transcatetere mediante radiofrequenza della via lenta del circuito di rientro nodale.

BACKGROUND: Junctional beats (JB) are often recorded during slow pathway (SP) radiofrequency (RF) ablation in patients with atrioventricular nodal reentrant tachycardia (AVNRT). Neither the correlation between JBs and SP potentials nor the role of mechanically-evoked JBs has been clarified yet. METHODS: Two hundred-eleven consecutive patients, with common AVNRT, underwent RF transcatheter ablation guided by Jackman SP potential searching. If we were unable to record an SP potential or if 4 RF pulses delivered on ideal ablation sites were ineffective, the ablation was carried out on anatomical landmarks. Light pressure was applied with the ablation catheter to each ablation site before RF delivery in order to evaluate the inducibility of JBs. RESULTS: Transcatheter ablation was performed successfully in 209/211 (99%) patients. In 17 (8.1%) patients, no SP potential was recorded. JBs were observed more often delivering RF in the mid-septal region, whereas SP potentials were more often recorded at the base of the Koch triangle. The success rate (successful pulses/overall pulses) was higher in the mid-septal (58.6% in M1, 77.8% in M2) than in the postero-septal region (4% in PSC, 16.8% in P1). JBs showed a higher specificity (73.2 vs 5.3%), positive (55.5 vs 24.6%) and negative predictive value (97.3 vs 63.8%) than SP potential in identifying the successful ablation site. Mechanical JBs were evoked in 23 patients on 29 ablation sites, and 18/29 (62.1%) of them were successful ablation sites. CONCLUSIONS: The recording of JBs during or before RF ablation is a useful parameter to guide SP ablation in patients with AVNRT. Although the underlying mechanism has not been clarified yet, their preferential occurrence in the mid-septal region suggests that they might be due to thermal stimulation of compact atrioventricular node.

Determinants of efficacy of atrial pacing in preventing atrial fibrillation recurrences.

INTRODUCTION: Several studies have shown that single or dual site atrial pacing is effective in reducing the frequency of recurrent atrial fibrillation (AF) in selected patients. However, it is still unclear what the best predictors are of long-term efficacy of atrial pacing. METHODS AND RESULTS: Forty-seven patients with paroxysmal AF requiring demand pacing underwent electrophysiologic study and dual chamber pacemaker implant. After 4 months of follow-up, patients were divided into two groups according to the presence (group 1) or absence (group 2) of symptomatic AF recurrences. Atrial pacing markedly reduced AF recurrences in all patients. Twenty-four patients were free of arrhythmia. The basal state conduction times (CTs) and the incremental conduction times (ICTs), during programmed electric stimulation between the high right atrium (HRA) and the coronary sinus ostium (CSos), but not between the HRA and the His-bundle region, were significantly longer in group 1. There was no statistical difference in the effective refractory period (ERP) recorded at the HRA, the low right atrium (LRA), and the CSos between the two groups, whereas the differences between the greatest and least recorded ERPs measured from the HRA, LRA, and CSos (deltaERP) were significantly greater in group 1 patients. Two parameters were selected by discriminant multivariate analysis, namely deltaCTos (ICT-CT between HRA and CSos) and deltaERP. The first had a greater relative importance in predicting AF recurrence (r2 = 0.33 and r2 = 0.1, respectively). CONCLUSION: Single site atrial pacing is effective in reducing AF recurrences, with decreasing efficacy in patients with greater right atrial conduction delay and wider refractoriness dispersion.

Feasibility and safety of two French electrode catheters in the performance of electrophysiological studies.

UNLABELLED: The aim of this study was to analyze prospectively the feasibility and safety of using 2 Fr versus 6 Fr standard electrode catheters for diagnostic electrophysiological study. METHODS: Two hundred and five consecutive patients were randomized to receive the 6 Fr approach (3 quadripolar, 6 Fr, electrode catheters inserted through the left or right femoral vein and placed in the high right atrium, right ventricular apex, and His bundle area) or the 2 Fr approach (3 quadripolar, 2 Fr, electrode catheters inserted through a single, 7 Fr, triple lumen, guiding catheter and positioned at the same sites as the 6 Fr approach). RESULTS: Introduction time was shorter in the 2 Fr group (133.3 +/- 65 s, range 87-669 s) than in the 6 Fr group (242.8 +/- 91.8 s, range 168-1024 s, P < 0.001). The overall fluoroscopy time was longer in the 2 Fr group (141.2 +/- 40.1 s, range 78-312 s) than in the 6 Fr group (126.4 +/- 39.7 s, range 58-341 s, P = 0.009). However in the last 100 patients there was no more difference between the two groups (137.6 +/- 28.2 s vs 128.4 +/- 23.2 s, P = 0.07). There was no significant difference between 2 Fr and 6 Fr groups in the mean atrial (5.9 +/- 2.2 mV, range 2.2-11.3 mV, vs 6.1 +/- 2.3 mV, range 2.4-12.4 mV, P = 0.57) and ventricular (5.6 +/- 2.1 mV, range 1.9-9.7 mV, vs 5.7 +/- 2.2 mV, range 2.3-10.5 mV, P = 0.66) activation potential amplitudes recorded during sinus rhythm, or in the rate of stable His bundle potential recording (P = 0.3), and catheter dislodgment (P = 0.54). The overall number of complications was significantly higher in the 6 Fr group than in the 2 Fr group (29 vs 5, P = 0.001), as well as the number of entry site related complications (3 vs 12, P = 0.02) and catheter manipulation related complications (2 vs 17, P < 0.001). CONCLUSIONS: The results of this study show that the use of 2 Fr electrode catheters reduces the rates of entry site and catheter manipulation related complications during EPS. Despite their small size, these catheters allow quick and precise positioning of the electrode.

Radiofrequency modification of the atrioventricular node in patients with chronic atrial fibrillation: comparison between anterior and posterior approaches.

INTRODUCTION: We compared, in a prospective and randomized fashion with a cross-over design, the anterior and posterior approaches to radiofrequency (RF) modification of the AV node in patients with chronic atrial fibrillation. METHODS AND RESULTS: Thirty-three patients were randomized to receive first an anterior (group I) or posterior (group II) approach for RF modification of AV nodal conduction. Patients who did not fill the endpoint ventricular rate (< 90 beats/min) were crossed over to the alternative approach. After the anterior approach in group I patients, mean ventricular rate was significantly lower than in group II patients after the posterior approach (79.6 +/- 18.8 beats/min vs 110.8 +/- 16.2 beats/min, P < 0.001). In group I, 14 (82%) of 17 patients fulfilled the endpoint, 1 (6%) had complete AV block, and 2 (12%) were crossed over to the posterior approach fulfilling the endpoint. In group II, 4 (25%) of 16 patients fulfilled the endpoint. No transient or permanent high-degree AV block was observed. Among the 12 patients who were crossed over to the anterior approach, 8 fulfilled the endpoint, whereas 4 had permanent high-degree AV block. RF ablation carried out only in the anterior region was safer than a stepwise approach (6% vs 33% incidence of AV block), even though the difference did not reach statistical significance (P = 0.09). CONCLUSION: Posterior AV nodal modification is less effective but safer than anterior AV nodal modification. However, to reduce the incidence of AV block, the anterior approach is preferable to a stepwise approach from the posterior to the anterior zone.

Dual chamber pacing in hypertrophic cardiomyopathy: influence of atrioventricular delay on left ventricular outflow tract obstruction.

The impact of the duration of atrioventricular (AV) delay on obstruction in hypertrophic cardiomyopathy was evaluated in 12 patients by cardiac catheterization, and in 8 of them also by Doppler echocardiography. The AV delay was programmed in random order at 125, 100 and 75 ms in the invasive study and at 120, 100 and 80 ms after pacemaker implantation. The arterial pressure did not changed throughout the studies, whereas the gradient decreased significantly by reducing the AV delay value; the greater gradient reduction was obtained, in both studies, with the AV delay set between 75 or 80 and 100 ms. QRS duration increased significantly by reducing the AV delay during both studies. The widest QRS was not associated with the smallest gradient in all patients. Changes in gradients were similar during the invasive and noninvasive protocols.

Inappropriate sinus tachycardia after radiofrequency ablation of para-Hisian accessory pathways.

INTRODUCTION: Inappropriate sinus tachycardia (IST) has been observed following radiofrequency ablation (RFA) of the AV nodal fast pathway. This study was aimed to prospectively analyze the incidence and clinical significance of IST following RFA of para-Hisian accessory pathways (APs). METHODS AND RESULTS: Twenty-eight patients (pts) with para-Hisian APs underwent RFA. An AP was defined as para-Hisian whenever its atrial and ventricular insertions were associated with a His-bundle potential > or = 0.1 mV. RF current was always delivered at the atrial aspect of the tricuspid annulus, to a site where the His-bundle potential was < 0.15 mV. Time- and frequency-domain analysis of heart rate variability was performed in 22 patients, before and after RFA. Abolition of AP conduction was obtained in all pts, and no AV conduction alteration occurred. Six pts (21.4%) presented with IST 45 to 240 minutes after the ablation procedure. In 5 of them, IST disappeared spontaneously within 72 hours, whereas in 1 pt beta-blockers were required for 2 months. The atrial potential amplitude (1.217 +/- 0.264 mV vs 0.882 +/- 0.173 mV, P = 0.009) and A/V potential amplitude ratio (2.633 vs 1.686, P = 0.05) were significantly higher in pts who developed IST than in those who did not. A marked decrease in heart rate variability was observed only in pts who developed IST. CONCLUSION: IST is a relatively frequent complication after RFA of para-Hisian APs: it is generally short-lasting and usually does not require any treatment. IST after catheter ablation is likely to depend upon transient parasympathetic denervation of the sinus node.