QT dispersion in hemodialysis and CAPD patients.

Prolongation of repolarization dispersion (QT interval dispersion) measured from the 12-lead surface ECG has been associated with sudden cardiac death and ventricular tachyarrhythmias in a variety of cardiac disorders. The aim of our study was to assess the effects of hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) on QT dispersion in end-stage renal disease patients. 20 chronic HD patients (mean age 57.75 +/- 13.79 years) and 20 CAPD patients (mean age 50.79 +/- 14.94 years) who had no complaints and symptoms of cardiac arrhythmias as well as 20 healthy volunteers (mean age 48.74 +/- 10.88 years) underwent ECG testing. All HD patients were on bicarbonate three times weekly with cuprophane capillaries. 12-lead ECGs were recorded on the day after HD. The CAPD patients were on a standard CAPD program (four times daily with 2,000 cm(3) peritoneal fluid). ECGs were recorded when the patients were receiving their regular standard CAPD program. All ECGs were analyzed manually by one observer. There were no statistically significant differences in dialysis duration, blood urea nitrogen, creatinine, sodium, calcium, and parathormone values between the HD and CAPD patients. The serum potassium values were significantly higher in HD patients when compared to CAPD patients. There was no difference in the mean of maximal QT among all three groups. The rate of QT interval dispersions was significantly higher in HD and CAPD patients as compared with healthy controls (p < 0.05). There was no statistically significant difference in the QT dispersion rates between HD and CAPD patients. In conclusion, there is a tendency to cardiac arrhythmias in HD patients during the postdialysis period. Although CAPD patients are receiving dialysis daily, they also have higher rates of QT dispersions and accordingly a tendency to arrhythmias.

Anticardiolipin antibodies in Behçet's disease: a reassessment.

OBJECTIVE: To assess the frequency and clinical relevance of anticardiolipin antibodies (aCL) in Behçet's disease (BD). METHODS: IgG, IgM and IgA aCL isotypes were investigated by ELISA in 128 patients with BD, 143 healthy controls and 20 systemic lupus erythematosus (SLE) patients. RESULTS: The IgA binding index (BI) was slightly elevated in BD compared with healthy controls (120+/-53 vs 107+/-46, P=0.02), whereas IgG and IgM aCL levels were not significantly different (IgG, BD 2.5+/-2.4 G phospholipid (GPL), healthy controls 2.8+/-3.6 GPL, P=0.6; IgM, BD 0.7+/-0.9 M phospholipid (MPL), healthy controls 0.9+/-1.3 MPL, P=0.6). The frequency of aCL positivity was 7% in BD (IgG 0.8%, IgM 1.6%, IgA 4.6%), 50% in SLE and 5.6% in healthy controls. IgA BI was elevated in the HLA-B5-negative group compared with HLA-B5-positive patients (P<0.005). In a literature review, the frequency of aCL was found to be 9.5% in studies from Turkey compared with 25.5% in other series (P<0.0001). CONCLUSION: These results do not suggest a primary role for aCL in BD. A significantly lower frequency of aCL in Turkish BD patients than in other series indicate that regional determinants, whether environmental or genetic, might also play a role in controlling aCL production in BD.

Correlation of myocardial fractional flow reserve with thallium-201 SPECT imaging in intermediate-severity coronary artery lesions.

PURPOSE: The purpose of this study was to compare the measurements of fractional flow reserve of the myocardium (FFRmyo) with results of quantitative coronary angiography (QCA) and stress single-photon emission computed tomography thallium-201 (SPECT 201Tl) imaging in patients with intermediate-severity coronary artery disease (ISCAD). METHODS: We prospectively evaluated 40 lesions of QCA-determined ISCAD in 30 patients (age, 53.3 +/- 10.2 years; 67% male) using a 0. 014 inch pressure wire during elective coronary angiography and compared the results with those of SPECT 201Tl performed within a week of angiography. RESULTS: There was a moderate negative correlation between percent diameter stenosis (%DS) and FFRmyo (53.1 +/- 13.4% and 0.75 +/- 0.09, respectively; r = -0.40; p = 0.01). Twenty-two out of 40 vascular territories (55%) were found to have perfusion defects (Group 1) and 18 territories (45%) were found to be normal (Group 2). While QCA-determined stenosis severity was not different between Group 1 and Group 2 (56 +/- 12% vs. 50 +/- 16%, respectively; p = 0.3), FFRmyo was found to be significantly different between the two groups (0.68 +/- 0.05 vs. 0.83 +/- 0.05, respectively; p = 0.001). When %DS and FFRmyo results were dichotomized as abnormal by 50% and < 0.75, respectively, and SPECT 201Tl was taken as the gold standard, sensitivity, specificity, positive predictive value and negative predictive value of %DS and FFRmyo were 0.55 vs. 0.91, 0.56 vs. 1.0, 0.60 vs. 1.0 and 0.50 vs. 0. 90, respectively. CONCLUSION: While FFRmyo seems to accurately predict the presence of ischemia on SPECT 201Tl in patients with ISCAD, QCA does not reliably assess the physiologic impact of the same lesions.

Measurement of myocardial fractional flow reserve during coronary angioplasty in infarct-related and non-infarct related coronary artery lesions.

Myocardial fractional flow reserve (FFRmyo) has been demonstrated to be a useful method for determining the physiologic importance of a given coronary lesion. However, the reliability of the FFRmyo measurement is unknown in infarct-related arteries (IRA). The aim of this study was to measure and correlate the FFRmyo results of 14 consecutive patients who had recent acute myocardial infarction (AMI) (Group 1) with 14 consecutive patients who didnOt have AMI (Group 2) before and after percutaneous transluminal coronary angioplasty (PTCA). Quantitative coronary angiography (QCA) and FFRmyo measurements were determined both before and after optimal PTCA for all patients. FFRmyo was measured by use of a 0.014 inch guidewire as the ratio of the pressure distal to the target lesion to the aortic pressure taken during the maximal hyperemia induced by intracoronary adenosine. There were no differences between the two groups related to gender, target artery reference diameter, minimal luminal diameter and percent diameter stenosis of the vessel both before and after PTCA. While FFRmyo results after PTCA were not different between the groups, they were statistically different before PTCA (Group 1: 77.6+/-5.4%, Group 2: 63.3+/-8.4%; p<0.001). Although QCA-determined percent diameter stenosis revealed a significant degree of stenosis (66.5+/-10.5%) for Group 1, FFRmyo values were higher than 75% (77.6+/-5.4%), indicating insignificant stenosis. Thus, it was concluded that FFRmyo measurements before PTCA were significantly different between IRA and non-IRA and that the method may not be valid for the determination of stenosis significance in IRA.

Intravenous Propafenone for Conversion of Atrial Fibrillation or Flutter to Sinus Rhythm: A Randomized, Placebo-controlled, Crossover Study.

BACKGROUND: Propafenone has been claimed to be effective in converting atrial fibrillation and flutter to sinus rhythm; however, controlled clinical trials have reported variable results, and data about the safety of propafenone in the setting of heart failure are lacking. The aim of the present study was to evaluate the efficacy and safety of intravenous propafenone in converting atrial fibrillation and flutter to sinus rhythm. METHODS: Sixty patients with acute (<72 h) or chronic atrial fibrillation or flutter were included in a randomized, placebo-controlled, conditional cross-over study. Twenty eight patients, of whom 12 were in New York Heart Association class III and IV, had heart failure. Patients received intravenous propafenone (2 mg/kg in 10 minutes) and placebo subsequently at 1 hour intervals if sinus rhythm was not achieved. The patients' rhythms were continuously monitored for 1 hour and a 12-lead electrocardiogram, a 1-minute continuous rhythm strip and vital signs were recorded at baseline and at 15, 30, 45, and 60 minutes after the administration of each drug. RESULTS: Twenty of teh 59 patients (34%) treated with propafenone converted to sinus rhythm, while only 4 of the 50 patients (8%) treated with placebo converted (P <.001). Propafenone was more effective in patients with acute (<72 h) atrial fibrillation (64.5%). The conversion rate with propafenone was not significantly different from placebo in patients with atrial flutter and chronic atrial fibrillation (>72 h). Propafenone significantly decreased (P <.005 vs placebo) mean ventricular rate in nonresponders with a baseline heart rate of more than 100 beats/min. No clinically significant adverse effect occurred. CONCLUSIONS: We conclude that intravenous propafenone treatment is effective for converting acute atrial fibrillation; however, it seems unlikely to be beneficial in atrial flutter and chronic atrial fibrillation. Propafenone decreases ventricular rate in nonresponders, and a single dose of propafenone is relatively safe even in moderate-to-severe heart failure.