Sidebranch occlusion in direct intracoronary stenting: predictors and results.

We assessed the angiographic predictors and results of major (> 1 mm) sidebranch occlusion (SBO) following direct intracoronary stenting (DS) in 86 patients. The occlusion of a sidebranch is a well-defined risk after balloon angioplasty and stenting. However, the impact of direct stenting without predilatation on the coronary flow of sidebranches emerging within the stented segment has not been studied solely. A total of 111 sidebranches were analyzed. Sidebranch type, take-off angle, ostial involvement and procedural characteristics were evaluated. Nine out of 111 (8%) stent-covered sidebranches were occluded. Sidebranches with > 50% stenosis that take off within or just beyond the diseased portion of the lesion (unfavorable morphology) were the most powerful morphologic predictor of SBO (odds ratio: 8.0; 95% confidence interval: 1.5--40.8; p = 0.007). Take-off angle of the sidebranch was not found to have any effect on SBO. Post-stent dilation using high-pressure inflation (15.0 +/- 2.1 atmospheres), inflation (odds ratio: 1.1; 95% CI: 1.0--1.2; p = 0.038), and 3 times inflation (odds ratio: 4.5; 95% CI: 1.1--18.3; p = 0.023) were the procedural predictor of SBO. Of those 40 unfavorable morphologies, seven (17.5%) were occluded compared to 2.8% (2/71) of the favorable morphologies. Nine out of 9 (100%) occluded after high-pressure inflation. Three patients complained of chest pain and 1 had non-Q wave myocardial infarction attributed to SBO. These findings indicate that the incidence of SBO and complications are less than expected and has a favorable outcome in direct intracoronary stenting.

Comparison of the three different formulas for Doppler estimation of pulmonary artery systolic pressure.

Noninvasive pulmonary artery systolic pressure (PASP) is calculated by summing the right ventricular systolic pressure obtained from Doppler velocity of regurgitant flow through the tricuspid valve and the right atrial (RA) pressure. The RA pressure is generally assumed from different formulas. An accurate RA pressure estimation will add precision to PASP calculation. One of the methods to estimate RA pressure is the inferior vena cava collapsibility index (IVCCI). In 45 patients referred for right heart catheterization, the authors tested a formula for the calculation of PASP based on the estimation of RA pressure from IVCCI and compared this method with two other formulas. The first method (method 1) assumed a constant RA pressure of 10 mm Hg irrespective of right ventricular pressure. The formula used was Doppler gradient + 10 (mm Hg). In the second method (method 2), a clinical estimate of RV pressure was made from the formula: right ventricular-right atrial Doppler gradient x 1.1 + 14. In the third method (method 3), the patients were classified into three groups on the basis of IVCCI: group A, IVCCI greater than 45%; group B, IVCCI between 35% and 45%; and group C, IVCCI less than 35%. The formula used was Doppler gradient + 6, 9, or 16 mm Hg in the presence of normal (group A), moderately reduced (group B), or markedly reduced (group 3) IVCCI. A good correlation between Doppler and catheter measurements of PASP was found for methods 1, 2, and 3, respectively (r=0.8933, SEE=6.4, r=0.8921, SEE=7.0, and r=0.8989, SEE=6.7). Correlation between invasive and noninvasive PASP was similar with the three methods, but correlation in method 2 was less satisfactory than with the other two methods. The mean difference between Doppler-derived and hemodynamic PASP was also high in method 2. In conclusion, the result of this study validates a relatively new, simple echo-Doppler formula for Doppler estimation of PASP based on a noninvasive evaluation of RA pressure through the IVCCI. However, this method is not better than the traditional method 1 for noninvasive PASP estimation.

Percutaneous balloon valvuloplasty for severe mitral stenosis in pregnancy. Four case reports.

Four pregnant women with mitral stenosis who did not respond to medical therapy underwent successful percutaneous balloon valvuloplasty with complete resolution of their symptoms. Their clinical features and echocardial and hemodynamic data are presented. The procedures and the remainder of their pregnancy were uncomplicated. Percutaneous balloon valvuloplasty of the mitral valve is a safe and effective alternative to surgical therapy if medical management is unsuccessful.

Is there any association between dissection after successful percutaneous transluminal coronary angioplasty and late restenosis? An angiographic study.

Restenosis continues to be the most important limitation of percutaneous transluminal coronary angioplasty (PTCA). Many clinical, angiographic, and procedural variables are thought to be related to the development of restenosis. This study was aimed at investigating the effects of no dissection, minor dissections, and major dissections on the long-term outcome of lesions after successful PTCA. The study group comprised 91 patients with 100 lesions who underwent successful PTCA and in whom follow-up coronary angiography was performed at 8.8 +/- 7.2 (two to twenty-three) months after dilation. Dissections were classified according to the National Heart, Lung, and Blood Institute criteria. Restenosis was defined as more than 50% stenosis at follow-up angiography. Restenosis rates were found to be 22% in the no-dissection group (10 restenoses in 46 patients), 27% in the minor dissection group (11 restenoses in 40 patients), and 36% in the major dissection group (5 restenoses in 14 patients). The authors applied corrected Yates Chi-square test and no difference was observed in the restenosis rate between the group without any dissections and that with minor dissections (P > 0.05). However, a statistically significant difference was observed in the restenosis rate between the major dissection group and the other two groups (P < 0.05). The authors conclude that the occurrence of major dissections after successful PTCA may adversely affect the long-term outcome and may increase the restenosis rate.

Does increased lipoprotein (a) impair the effectiveness of thrombolysis with streptokinase?

Although lipoprotein (a) [Lp(a)] has been shown to interfere with thrombolysis in vitro, its effects on thrombolytic therapy in patients with acute myocardial infarction (MI) are not clear. The authors evaluated 32 male patients ages thirty-five to seventy-five (mean fifty-two +/- ten) with the diagnosis of acute MI who underwent thrombolytic therapy with 1,500,000 units of intravenous streptokinase. All patients underwent coronary angiography within seven days of the infarction from which the thrombolysis in myocardial infarction (TIMI) flow grades of the infarct-related artery, coronary scores, and ejection fraction were determined. Anterior MI was found in 19 patients (59.4%), inferior MI in 12 (37.5%), and posterolateral MI in 1 patient (3.1%). They found that 6 patients (18.8%) had TIMI flow 0 to 1, and 26 patients (81.2%) had TIMI flow grade 2 or 3. The Lp(a) levels ranged from 0.1 to 60 mg/dL with a mean of 8.6 +/- 17 mg/dL. Eight (25%) of the patients had Lp(a) levels above 30 mg/dL. The TIMI flow rates were not found to be lower in patients with high Lp(a) levels (P > 0.05), and there was no significant correlation between the TIMI flow rates and the Lp(a) levels (r = 0.28). There was a good correlation between coronary scores and Lp(a) levels (r = 0.87). They conclude that although there is a good correlation between the extent of coronary atherosclerosis and Lp(a) levels, Lp(a) is not a strong predictor of the outcome of thrombolytic therapy.