Use of intraventricular dispersion of the peak diastolic flow velocity as a marker of left ventricular diastolic dysfunction in patients with atrial fibrillation.

The aim of this study was to evaluate the use of intraventricular dispersion of the peak diastolic flow velocity as a marker of left ventricular diastolic dysfunction in patients with atrial fibrillation. Regional diastolic flow velocity patterns at 1, 2, and 3 cm away from the mitral tip toward the apex were simultaneously recorded with the mitral flow velocity pattern by using pulsed Doppler echocardiography in 24 patients with atrial fibrillation before electrical or medical cardioversion. Echocardiographic examination was repeated after 10 to 30 days (ie, at the time of recovery of left atrial mechanical functions) after cardioversion of atrial fibrillation in all patients. Thirteen patients were found to have diastolic dysfunction; the remaining 11 patients with a normal E/A ratio constituted the control group. Afterward, the data recorded before the cardioversion were analyzed for each patient. In subjects with normal diastolic function, the peak diastolic flow velocity (PDFV) at the mitral tips also was maintained at the positions 1 to 3 cm away from the tip in the left ventricular cavity (PDFV at the mitral tips: 0.84 m/s, PDFV at 3 cm: 0.85 m/s; P =.34). In contrast, the regional PDFV progressively decreased toward the apex in patients with diastolic dysfunction (PDFV at the mitral tips: 0.82 m/s, PDFV at 3 cm: 0.63 m/s; P =.0004). Only 77% of the initial velocity was maintained at 3 cm away from the mitral tips in patients with diastolic dysfunction, whereas almost 100% of the initial velocity was preserved in patients with normal diastolic function (P <.001). These findings suggest that the assessment of the intraventricular decrease in mitral PDFV may be used as a reliable marker of diastolic dysfunction in patients with atrial fibrillation.

Compliant vs non-compliant balloons. A prospective randomized study.

In this prospective randomized trial we explored the possibility of different procedural outcomes with regard to compliant (polyolefin copolymer (POC)), and non-compliant (polyethylene terapthelate (PET)) balloon materials commonly used during percutaneous transluminal coronary angioplasty (PTCA). For this purpose, 51 female and 149 male (total 200) patients were randomized to 100 compliant and 100 non-compliant balloons. Only single lesions were included in the study and patients who had PTCA for more than one lesion in different segments at different sessions were each entered separately (there were actually 49 female and 143 male patients). PTCA procedures were performed in conjunction with quantitative coronary angiographic techniques and the films were reviewed by two investigators in a blinded fashion. Statistical analysis for various procedural end-points were performed by non-paired Student t test with statistical significance being p < 0.05. There were no differences in demographic and clinical characteristics between groups. Lesion characteristics of both groups were exactly matching for vessel size, balloon size, balloon vessel ratio, minimal luminal diameter and percent stenosis of the index lesion. Similarly, minimal residual diameter, percent residual stenosis, net gain, densitometric net area gain, and maximum pressure (2.2 +/- 5 mm vs 2.1 +/- 0.6 mm, 18 +/- 17% vs 23 +/- 15%, 0.8 +/- 0.5 mm vs 0.8 +/- 0.6 mm, 48 +/- 25% vs 48 +/- 26%, 7.3 +/- 2 atm. vs 6.8 +/- 3 atm., respectively) values were not statistically different between compliant and non-compliant balloon groups. Major in-hospital complications, dissections caused by the study balloon (mostly type A and B), crossover and bail-out procedures (5 vs 3, 34 vs 32, 4 vs 3, 13 vs 14, respectively) were similar for both compliant and non-compliant balloon groups. Study balloon success rate (defined as < 50% residual stenosis or > 20% net gain in the absence of major in-hospital complications, crossovers and bail-outs) and overall procedural success rate (80% vs 74%, 90% vs 85%) were not statistically different for compliant and non-compliant balloons. In conclusion, we did not observe any statistically significant difference between compliant and non-compliant balloons in terms of immediate procedural results.

Directional coronary atherectomy versus coronary angioplasty in vessels larger than 3 mm in diameter.

It has been proposed that directional coronary atherectomy (DCA) should be an intervention of choice in larger vessels as one can achieve a greater minimal luminal diameter with DCA than with percutaneous transluminal coronary angioplasty (PTCA). This in turn should translate into a higher success rate and may even reduce the restenosis rate. The aim of this study was to compare DCA versus PTCA in vessels > 3 mm in diameter. One hundred fifty consecutive patients who met the inclusion criteria and had DCA were compared to 150 similarly selected PTCA patients. PTCA patients were selected from the era immediately preceding the advent of DCA so that selections bias could be excluded. All patients with ostial lesions, restenosis, vessels < 3 mm in diameter, and vessels with more than two significant lesions were excluded. Distal segments and circumflex cases were excluded as they formed a small subsegment. Both groups were similar in terms of demographic, clinical and angiographic variables. Quantitative analysis showed that the initial net gain was significantly greater in the DCA group than in the PTCA group (2.36 +/- 0.8 mm vs. 1.78 +/- 0.7 mm; p < 0.05). Residual stenosis was 11% with DCA compared to 33% with PTCA (p < 0.05). Despite these improved anatomical results the procedural success rates were similar (91.5% vs 84%). Major in hospital complications (death, acute occlusion, MI, emergency CABG, re-do) were higher in the DCA group than in the PTCA group (12% vs 6%). Clinical follow-up on 276 patients (150 DCA vs 126 PTCA) showed a 6 month clinical restenosis rate of 18% vs 28%, respectively. The incidence of re-do in 24 hours for acute occlusion was 6% for DCA and 1% for PTCA. In large-sized vessels DCA results in a lower restenosis rate. However, despite a lower incidence of residual stenosis, the complication rate tends to be higher with DCA (p < 0.05).