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P Turco

Publications and source records attributed to P Turco.

At least 19 recordsLinked to original sources
PubMed2003

Clinical impact (cost-effectiveness) of qualifying atypical squamous cells of undeterminate significance (ASCUS) in cases favoring a reactive or dysplastic process.

The cost-effectiveness of qualifying ASCUS cases into two different subcategories, favoring a reactive (ASCUS-R) or dysplastic process (ASCUS-S), was evaluated at the Centro per lo Studio e la Prevenzione Oncologica of Florence in a prospective study. The study determined the positive predictive value (PPV) for histologically confirmed cervical intraepithelial neoplasia grade 2 (CIN2) or more (CIN>) severe lesion of the two ASCUS subgroups. ASCUS-S had a PPV (10.78%) comparable to low-grade squamous intraepithelial lesions (LSIL) (11.40%). For ASCUS-R cases, the recommendation of 6-mo repeat cytology prompting colposcopy in cases of persistent ASCUS or more severe cytology was also effective, as it selected a subgroup with a relatively high PPV (10.34%). The cost-effectiveness of a protocol based on ASCUS qualification was compared with two other possible options for nonqualified ASCUS cases: immediate colposcopy and colposcopy in persistent ASCUS at 6-mo repeat cytology. The detection rate of CIN2> was substantially higher using ASCUS qualification (35.9 vs 14.8 or 17.1). The cost per ASCUS subject was euro 24.99, 27.11, or 25.14 and that per CIN2> detected was euro 697, 1,831 or 1,470 for the three options, respectively. The evidence that ASCUS detection option implies a higher detection rate of CIN2> and subsequently a lower cost per CIN2> detection must be considered with caution and deserves confirmation by other comparative studies.

Cervix Uteri↗
PubMed2003

Assessment of inhaled BDP-dose dependency of exhaled nitric oxide and local and serum eosinophilic markers in steroids-naive nonatopic asthmatics.

The aim of the present study was to assess the dose-dependency from inhaled steroids of changes of airways inflammation [eosinophils count and eosinophil cationic protein (ECP)] measures in induced sputum and in serum, as well as that of exhaled nitric oxide. Twenty steroid-naive patients with nonatopic asthma of mild to moderate degree [forced expiratory volume in 1 s (FEV1) = 70% of predicted] and with negative response to the standard tests for allergy were selected; after a 1-week run-in period they were randomized to receive a 12-week treatment period of inhaled beclomethasone dipropionate dry powder given with the Pulvinal inhaler (Clenil P, Chiesi Farmaceutici S.p.A., Parma, Italy) in two different dose regimens, 400 microg bid (high dose) or 200 microg bid (low dose), over a double blind, parallel groups design. The following outcome measures were assessed in baseline and after 1, 6 and 12 weeks of treatment: FEV1 (l), eosinophils count in sputum (%), is ECP (microg/l), serum eosinophils count (%), serum ECP (microg/l) and exhaled NO (ppb). The results showed that all the considered parameters improved in both groups: the increase over baseline of FEV1 and the decrease of NO were significant at any time in the high-dose group and only at week 12 in the low-dose group (NS between groups), whereas the markers of eosinophilic activity showed more consistent reductions in the high-dose than in the low-dose group when measured in induced sputum (P < 0.05 between groups after 6 and 12 weeks for eosinophils count and after 12 weeks for ECP). Decreases over baseline of markers measured in serum were more rapid in the high-dose group, without differences between groups. A marked trend towards a negative correlation was found between FEV1 and ECP, (r = -0.72, P < 0.05), between FEV1 and eosinophils in sputum (r = -0.31, NS) and between FEV1 and exhaled NO (r = -0.38, NS), all of them only in the high-dose group. The results of the study demonstrate that changes of levels of eosinophilic activity in the airways are dependent from the daily dose of inhaled steroids when measured in induced sputum and that the local assessment can therefore represent a practical and noninvasive method to monitor the extent of airways inflammation.

Administration, Inhalation↗
PubMed2002

Basic variables at different positivity thresholds of a quantitative immunochemical test for faecal occult blood.

OBJECTIVES: Screening by faecal occult blood testing (FOBT) is effective in decreasing mortality and incidence of colorectal cancer (CRC). Immunochemical tests have proved to be more cost effective than guaiac FOBTs. The latex agglutination test (LAT) has the advantage of being a fully automated, quantitative test. The aim of this study is to interpret the overall experience with LAT according to different positivity thresholds. SETTING: A population based screening programme is currently running involving subjects aged 50-70, invited every 2 years to have an FOBT. LAT is the standard screening test and has a positivity threshold for further diagnostic tests of 100 ng haemoglobin/ml of sample solution. METHODS: Positivity rates, detection rates for CRC high risk adenomas, and positive predictive values for CRC, high risk adenomas, and low risk adenomas were calculated for several positivity thresholds. RESULTS: 19,132 attendances at screening were recorded (11,774 at first screening, 7358 at subsequent screenings). Progressively increasing the positivity threshold from 100 to 200 ng/ml showed (a) a decrease in positivity rate; (b) a decrease in detection rates for CRC or high risk adenomas; (c) an increase in positive predictive values for cancer; (d) an increase in positive predictive value for high risk adenomas. CONCLUSIONS: Increasing the positivity threshold of the LAT reduces recall rate and improves positive predictive value for cancer or high risk adenomas but substantially decreases the detection rate of CRC and high risk adenomas. For this reason increasing the positivity cut off for LATs is not advisable. On the other hand decreasing the positivity threshold would increase recall rate and sensitivity of screening. Careful evaluation of sensitivity of the quantitative results of the LAT for interval cancers is needed to definitively assess the optimal positivity threshold for LATs in population based screening programmes.

Adenoma↗
PubMed2001

Measuring interval cancers in population-based screening using different assays of fecal occult blood testing: the District of Florence experience.

The fecal occult blood test (FOBT) has demonstrated its efficacy in reducing mortality from colorectal cancer (CRC). The guaiac-based FOBT has been criticized for its low sensitivity. In this study, two different assays for FOBT (guaiac or an immunochemical test based on reversed passive hemagglutination [RPHA]) were tested for comparison within a population-based screening program for colorectal cancer in the province of Florence (Italy). The proportional incidence method was used to calculate sensitivity for both FOBTs, according to rank of screening (first or repeat), age at entry (two groups of 50 to 59 and 60 to 70 years old) and lesion site (colon or rectum). When comparing FOBTs, the sensitivity multivariate Poisson regression was used to adjust for other variables. The sensitivity after the first 2 years was 50% (95% confidence interval [CI] 34% to 63%) for the guaiac test versus 82% (95% CI 67% to 92%) for RPHA. At multivariate analysis the risk of developing an interval cancer after a guaiac test is almost 3 times that after RPHA (rate ratio = 2.64; 95% CI 1.3 to 5.4). Our study confirms that RPHA is more sensitive than the guaiac test. The assumption that FOBT screening for CRC has to be based on a guaiac test should be reconsidered, and RPHA should be recommended as the standard FOBT for screening purposes.

Aged↗
PubMed2001

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.

Administration, Oral↗
PubMed2000

Screening for colorectal cancer by faecal occult blood test: comparison of immunochemical tests.

OBJECTIVE: To compare two immunochemical faecal occult blood tests based on reversed passive haemagglutination (RPHA) or latex agglutination (Hdia) in a population based screening setting. METHOD: Hdia was interpreted according to three positivity thresholds: 100, 150, or 200 ng of haemoglobin/mg of specimen solution. A total of 5844 subjects were recruited into the study, from 17432 invited subjects aged 50-70. RESULTS: Positivity rates were 3.3% for RPHA, Hdia100 3.5%, Hdia150 2.5%, Hdia200 2.0%. Among subjects complying with the diagnostic work up, colorectal cancer (CRC) was detected in 19 subjects (17 RPHA positive, 16 Hdia100 positive, 15 Hdia150 positive, 14 Hdia200 positive) and high risk adenoma/s in 41 subjects (28 RPHA positive, 32 Hdia100 positive, 29 Hdia150 positive, 25 Hdia200 positive). The prevalence of screen positive CRC in the population was for RPHA 2.9 per thousand, Hdia100 2.7 per thousand, Hdia150 2.6 per thousand, Hdia200 2.4 per thousand. The prevalence of screen positive high risk adenomas in the population was for RPHA 4.8 per thousand, Hdia100 5.5 per thousand, Hdia150 5.0 per thousand, Hdia200 4.3 per thousand. CONCLUSION: Hdia100 was as sensitive as RPHA for cancer and high risk adenomas. As Hdia is less technically complex than RPHA, it is a valid alternative to the latter, provided that full automation of the development procedure is available. Increasing the positivity threshold of Hdia up to 150 or 200 ng of haemoglobin/mg of specimen solution is not advisable as the increase in specificity is too small to justify the corresponding decrease in the detection of screen positive cancers in the population.

Adenoma↗
PubMed1999

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.

Aged↗
PubMed1999

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.

Aged↗
PubMed1999

Congestive heart failure induced by recipient atrial tachycardia conducted to the donor atrium after orthotopic heart transplantation: complete regression after successful radiofrequency ablation.

We describe the case of a 30-year-old female patient who developed an interatrial tachycardia from the recipient to the donor atrium associated with signs of congestive heart failure 5 years after orthotopic heart transplantation. The patient underwent catheter mapping followed by successful radiofrequency (RF) ablation at the site of the presumed electrical connection between the recipient and the donor atria, through the interatrial surgical suture line, with stable recovery of sinus rhythm and disappearance of signs of left ventricular dysfunction. RF catheter ablation is confirmed to be feasible and safe in the treatment of heart transplant patients even in the presence of rare forms of arrhythmias, thus offering a cure for tachycardia to these patients.

Adult↗
PubMed1999

Thromboembolism after atrioventricular node ablation and pacing: long term follow up.

OBJECTIVE: To assess the incidence of arterial embolic events in patients with high rate, drug resistant, severely symptomatic paroxysmal and chronic atrial fibrillation who have undergone atrioventricular (AV) node ablation and permanent pacing. DESIGN: Multicentre retrospective cohort study. PATIENTS AND MANAGEMENT: From May 1987 to January 1997, AV node ablation was performed in 585 severely symptomatic patients (mean (SD) age 66 (11) years) with high rate, drug resistant paroxysmal atrial fibrillation (308) or chronic atrial fibrillation (277). Lone atrial fibrillation was present in 133 patients, while the remaining 452 suffered from dilated, ischaemic, or valvar heart disease. Patients underwent VVIR (454) or DDDR (131) pacemaker implantation, after AV node ablation. Antiplatelet agents were given to 202 patients, warfarin to 187 patients. RESULTS: During a follow up of 33.6 (24.2) months, thromboembolic events were observed in 17 patients (3%); the actuarial occurrence rates of thromboembolism were 1.1%, 3%, 4.2%, and 7.4% after one, three, five, and seven years, respectively. Among five variables, univariate analysis showed that only the presence of chronic atrial fibrillation at the time of ablation (relative risk (RR) = 1.8, 95% confidence interval (CI) = 1.02 to 3. 20, p = 0.04) and the need for warfarin treatment (RR = 1.6, 95% CI 1.00 to 2.71, p = 0.048) were associated with a significantly higher risk of occurrence of thromboembolic events. On multivariate analysis the only predictor of embolic events during the follow up was the presence of chronic atrial fibrillation. CONCLUSIONS: Data from this large cohort of patients indicate a fairly low incidence (1.04% per year) of thromboembolic events after AV node ablation and pacing for drug refractory, high rate atrial fibrillation.

Aged↗
PubMed1999

[The predictive value of junctional beats during the radiofrequency transcatheter ablation of the slow pathway of the nodal reentry circuit].

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.

Cardiac Pacing, Artificial↗
PubMed1998

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.

Cardiac Catheterization↗
PubMed1998

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.

Aged↗
PubMed1996

Role of catheter-induced mechanical trauma in localization of target sites of radiofrequency ablation in automatic atrial tachycardia.

OBJECTIVES: We compared the efficacy of two different mapping techniques in identifying the ablation site for atrial tachycardia. Moreover, we evaluated the additive positive predictive value of mechanical interruption of atrial tachycardia to reduce the number of ineffective radiofrequency applications. BACKGROUND: Radiofrequency catheter ablation has been suggested as a highly effective technique to treat drug-resistant atrial tachycardia. However, irrespective of the mapping technique utilized, success was most often achieved with a large number of radiofrequency applications. METHODS: Forty-five patients with atrial tachycardia underwent radiofrequency catheter ablation. Mapping techniques included identification of earliest atrial activation and pace-mapping concordant sequence. RESULTS: Atrial tachycardia was successfully treated in 42 (93.3%) of 45 patients with a mean of 3.9 radiofrequency pulses/patient. An interval between the onset of the intracavitary atrial deflection and the onset of the P wave during atrial tachycardia (AP interval) > or = 30 ms (p < 0.001) and pace-mapping concordant sequence (p = 0.01) were all significant predictors of outcome. An AP interval > or = 30 ms and a pace-mapping concordant sequence were highly sensitive (92.8%, 95% confidence interval [CI] 80.5% to 98.5%; 85.7%, 95% CI 71.5% to 94.6%, respectively) but less specific (47.8%, 95% CI 37.9% to 58.2%, 36.8%, 95% CI 27.6% to 47.2%, respectively) in identifying the site of ablation. By using atrial tachycardia mechanical interruption combined with the AP interval >30 ms or the pace-mapping concordant sequence, we obtained a specifically of 76.5% (95% CI 66.4% to 84.0%) and 73.5% (95% CI 63.2% to 81.4%), respectively, and a positive predictive value of 49.2% and 44.6%, respectively. CONCLUSIONS: An AP interval > or = 30 ms and a pace-mapping concordant sequence were reliable mapping features for predicting the outcome of the ablation procedure. Mechanical interruption of atrial tachycardia improved the specificity and positive predictive value of these two mapping techniques.

Adolescent↗
PubMed1996

[Radiofrequency catheter ablation of atrial tachycardia: technique, results and follow-up].

BACKGROUND: Recently radiofrequency (RF) catheter ablation (CA) of atrial tachycardia (AT) showed to be highly effective with a low incidence of compliance. Aim of our study was to report the results and follow-up of RFCA of drug-refractory AT in 59 consecutive patients (pts). METHODS: Two mapping techniques were used to localize the ablation site of AT: the earliest atrial activation and the pace-mapping. Traumatic interruption of AT was used to verify the ablation site identified by the previous procedures. Moreover we evaluated the sensitivity, specificity and the positive predictive value of the three mapping techniques. RESULTS: AT was successfully treated in 55/59 (93.2%) pts with a mean of 4.0 +/- 3.8 (range 1-16) RF pulses for patient. The mean procedure time was 185.2 +/- 48.5 min with a mean rx-time of 41.5 +/- 21.3 min. An interval between the onset of the intracavitary atrial deflection and the onset of the P-wave, during atrial tachycardia, (AP interval) > or = 30 ms and pace-mapping concordant sequence were highly sensitive (90.9% and 89.1%) but less specific (49.2% and 33.9%) in identifying the site of ablation. By using atrial tachycardia traumatic interruption combined with the AP interval > 30 ms or the pace-mapping concordant sequence we obtained a specificity of 78.7% and 77.0% respectively and a positive predictive value of 48.0% and 46.8% respectively. Four recurrences (7.3%) were observed during a mean follow-up of 23.4 +/- 13.3 months. In the 22 (37.3%) pts with dilated cardiomyopathy, chest Xr and echocardiography showed a significant decrease of cardiothoracic index (0.56 +/- 0.08 pre ablation, 0.43 +/- 0.07 post ablation, p < 0.001) and end-diastolic diameter (64 +/- 8 mm pre ablation, 52 +/- 8 mm post ablation, p < 0.001) and a significant improvement of left ventricular ejection fraction (37 +/- 9% pre ablation, 48 +/- 11% post ablation, p < 0.05). CONCLUSION: The RFCA of AT was effective and safe. Moreover we observed a hemodynamic improvement in patients with reduced ejection fraction and increased cardiac volumes. An AP interval > or = 30 ms and the pace-mapping concordant sequence were reliable features to predict the outcome of the ablation procedure. Traumatic ablation of atrial tachycardia improved the specificity and the positive predictive value of these two mapping techniques and was able to predict the response to radiofrequency with a high specificity.

Catheter Ablation↗
PubMed1994

Role of transesophageal pacing in recurrent atrial fibrillation. Experience with propafenone.

UNLABELLED: To assess the role of transesophageal pacing (TP) at very high rates in the follow-up of patients with recurrent and sustained paroxysmal atrial fibrillation (AF) on therapy, the authors studied 15 patients (10 women, 5 men; aged forty-four to seventy-seven years old). Of them only 1 had a mild mitral regurgitation; none had hyperthyroidism or acute ischemic heart disease. They tested propafenone (P) at a dose of 1.4-2 mg/kg over ten minutes as an intravenous bolus and 0.5 mg/minute as intravenous maintenance for two hours and then 300 mg twice daily orally and chronically. Serial TPs at very rapid rates (up to 600 bpm) were performed to test the long-term efficacy of P to prevent paroxysmal AF. The mean follow-up was fifteen months (nine to twenty-four months). RESULTS: Intravenous P converted AF in five to ninety minutes (mean twenty-one minutes) in 9/15 patients (conversion rate of 60%); in an additional 4 patients oral P converted AF in two to fifteen hours. In the other 2 patients P failed to convert AF. Three patients experienced recurrence of AF in the early follow-up. Of the 10 patients who completed the entire protocol, only 1, who had mild mitral prolapse regurgitation and AF induction by TP, experienced new episodes of AF during follow-up. No significant side effects were noted during P therapy. CONCLUSIONS: Propafenone appears safe and effective for controlling and preventing recurrent and sustained AF. Transesophageal pacing is a valid tool for predicting the efficacy of long-term therapy in the follow-up of patients with paroxysmal atrial fibrillation.

Administration, Oral↗
PubMed1994

[Atrioventricular conduction before and after the radiofrequency catheter ablation of a nodal reentry tachycardia circuit].

Aim of our study was to retrospectively evaluate atrioventricular conduction 24 hours after selective radiofrequency catheter ablation of the fast pathway or after selective ablation of the slow pathway of the atrioventricular nodal reentrant tachycardia circuit. Electrophysiologic modifications were retrospectively analyzed in 47/48 patients successfully submitted to fast pathway ablation and in 90/93 patients successfully submitted to slow pathway ablation. The atrioventricular conduction intervals (P-Q and A-H), both anterograde and retrograde Wenckebach point, the effective refractory period of atrioventricular node and the atrioventricular node function curve were evaluated before and after selective radiofrequency catheter ablation of slow and fast pathway. We identified the fast pathway ablation potential as: A:V ratio > or = 2:1, His electrogram < or = 150 microV. The slow pathway potential was identified as the widest, sharpest and latest atrial electrogram recorded during sinus rhythm in the posteroseptal region of the atrioventricular junction or as the widest, sharpest and earliest observed during retrograde conduction. We observed a significant increase in the P-Q and A-H intervals in patients submitted to fast pathway ablation, while no significant modification of these parameters was appreciated in patients submitted to slow pathway ablation. No significant modification of anterograde Wenckebach point (NS) was observed in patients submitted to successfully ablation of fast pathway while a statistically significant increase in anterograde Wenckebach point (p = 0.03) was observed in patients submitted to slow pathway ablation. After selective fast pathway ablation, retrograde conduction was absent in 82.9% of patients submitted to ablation; in the remaining 17.1% a significant increase of retrograde Wenckebach point was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗