Circulating adhesion molecules in patients with stable coronary artery disease.

To evaluate platelet and endothelial function in patients with stable coronary artery disease (CAD), we investigated levels of the plasma-soluble (s) adhesion molecules E-selectin (sE-selectin), P-selectin (sP-selectin), and intercellular adhesion molecule-1 (sICAM-1) in 74 patients (mean age, 53 +/- 8 years) with angiographically documented coronary artery disease. Levels were compared to 27 matched healthy control subjects. Patients were excluded if they had recent cardiovascular events or any illness that might influence platelet and endothelial cell function. Concentrations of sP-selectin were significantly higher in patients with stable CAD (276 +/- 61 ng/mL) compared with control subjects (188 +/- 32 ng/mL) (P = .0001), whereas sE-selectin and sICAM-1 levels were similar between the 2 groups. Pooling both groups showed that sICAM-1 correlated weakly with triglycerides (r = 0.240, P = .01) and sP-selectin correlated weakly with low-density lipoprotein cholesterol (r = 0.204, P = .04). Although plasma sICAM-1 concentrations were significantly increased in hypercholesterolemic patients compared with those of normocholesterolemic patients (P = .04), sP-selectin and sE-selectin levels were similar between the 2 groups. In conclusion, significantly increased sP-selectin levels, indicating platelet activation, were found in patients with stable CAD. No other sign of endothelial cell activation in these patients could be detected. Moreover, sP-selectin levels seem to reflect the activation of platelets rather than of endothelial cells.

Methylene tetrahydrofolate reductase genotype and the risk and extent of coronary artery disease in a population with low plasma folate.

OBJECTIVE: To determine the effects of the thermolabile methylene tetrahydrofolate reductase (MTHFR) mutation on the presence and extent of coronary atherosclerosis in a population with low plasma folate. METHODS: 242 consecutive patients undergoing coronary angiography were prospectively evaluated for conventional risk factors, plasma homocysteine, vitamin B-12, and folate, and MTHFR genotype. The severity of coronary atherosclerosis was determined by the Leaman score. RESULTS: Mean (SD) plasma homocysteine was 15.6 (10) micromol/l in controls and 18.5 (11) micromol/l in patients with coronary artery disease (p > 0.05). Plasma homocysteine concentrations above 15 micromol/l were a risk factor for coronary artery disease (p = 0.03, risk ratio 2.1, 95% confidence interval (CI) 1.07 to 4.4). Homocysteine remained an independent risk factor on multivariate analysis when conventional risk factors were taken into account (p = 0.04). Homocysteine concentrations above 15 micromol/l were correlated with the extent of atherosclerosis (p = 0. 04, risk ratio 3.2, 95% CI 1.3 to 8.2). Homocysteine had no effect on other lipid variables (p > 0.05). Plasma folate was 15.8 (7.2) nmol/l in controls and 11.5 (2.9) nmol/l in patients with coronary artery disease. Plasma folate concentrations below 12.9 nmol/l (5.7 ng/ml) conferred a risk for coronary artery disease (p = 0.03, risk ratio 2.42, 95% CI 1.05 to 5.59). When the MTHFR genotype was determined, the TT genotype was present in 7.4% of patients and 5.2% of controls (p > 0.05). The prevalence of alleles was within the Hardy-Weinberg equilibrium (TT 7, CT 40, CC 53, chi2 = 2.3, p = 0.3). The highest homocysteine concentrations were found in patients with the TT genotype and folate below the median of the population (p = 0. 01). The extent of coronary atherosclerosis judged by the Leaman score was significantly higher in patients with the TT genotype (p = 0.03). CONCLUSIONS: Plasma homocysteine over 15 micromol/l was a significant risk factor for the presence and extent of coronary artery disease. The mean plasma folate of the population was low and correlated negatively with homocysteine. Although TT genotype was not an independent predictor of coronary artery disease, it was an important predictor of the extent of coronary atherosclerosis and plasma homocysteine, especially in the presence of plasma folate values below the median of the population. These findings may have important implications for folate replacement in patients with the TT genotype.

Left atrial appendage function in patients with cardioembolic stroke in sinus rhythm and atrial fibrillation.

The purpose of this study was to determine the left atrial appendage (LAA) function in patients with stroke. The study group consisted of 61 patients with stroke and 37 control subjects. Patients with stroke were divided into 2 groups on the basis of the presence of atrial fibrillation (group 1) or sinus rhythm (group 2). Group 1 showed a significant reduction of LAA flow velocities (13.2 +/- 6.4 cm/s versus 27.5 +/- 8 cm/s, P <.05) and significant increase in LAA areas (minimum area: 360.5 +/- 204 mm(2) versus 217.7 +/- 113.9 mm(2), P =.004). Group 2 showed a decrease in LAA flow velocities (17.7 +/- 8.2 cm/s versus 27.5 +/- 8 cm/s, P <.05), but no significant change was found in LAA areas. No significant difference was found in other parameters related to LAA. These findings show that a decreased LAA flow velocity is a risk factor for stroke in patients in sinus rhythm without LAA enlargement. Left atrial appendage area was increased in size only in patients with atrial fibrillation.

Hydatid cyst of the heart as a rare cause of embolization: report of 5 cases and review of published reports.

Cardiac hydatid cyst is seen infrequently, even in regions where hydatid cysts are endemic. We report 5 cases of cardiac hydatid cysts, which were diagnosed after an embolic event.

Angiotensin converting enzyme gene polymorphism and the risk and extent of ischemic heart disease among Turkish patients.

OBJECTIVE: To evaluate the effects of the angiotensin converting enzyme gene polymorphism on the presence and extent of coronary artery disease and myocardial infarction among Turkish patients. METHODS: In total 393 consecutive patients undergoing coronary angiography were evaluated for cardiac risk factors including the lipoprotein profile, lipoprotein (a), apoprotein B, and apoprotein A1 levels. The angiotensin converting enzyme genotype was determined by polymerase chain reaction. The extent of coronary atherosclerosis was determined from the angiograms using the Gensini and Leaman scores. RESULTS: The angiotensin converting enzyme genotype was found not to be associated either with coronary artery disease (odds ratio 0.81, P > 0.05) or with myocardial infarction (odds ratio 1.16, P > 0.05). Exclusion of high-risk individuals failed to reveal any association for these subgroups. Furthermore, there was no association between aneurysm formation and the genotype (P > 0.05). The lipid parameters were also not affected by the genotype (P > 0.05). However, the extent of coronary atherosclerosis determined by the Gensini score was related significantly to the genotype by multivariate analysis (P = 0.007). CONCLUSION: The DD genotype is not associated with coronary artery disease and myocardial infarction among these angiographically assessed Turkish patients, even when low-risk subgroups are analysed. Nonetheless, the extent of coronary atherosclerosis in patients with coronary artery disease is affected by their genotype.

Prediction of restenosis after successful percutaneous coronary angioplasty by dobutamine thallium-201 scintigraphy.

We evaluated the accuracy of dobutamine thallium-201 myocardial perfusion scintigraphy in predicting restenosis after successful percutaneous coronary angioplasty. Restenosis is one of the most important problems in patients who have undergone percutaneous coronary angioplasty. Exercise thallium-201 myocardial perfusion scintigraphy has been a well accepted non-invasive method to predict the restenosis of the dilated vessel after percutaneous coronary angioplasty, however, the role of thallium-201 myocardial perfusion using dobutamine, as a substitute for exercise in patients unable to exercise, in predicting restenosis is not well known. Therefore, 34 consecutive patients underwent dobutamine tomographic (single photon emission computed tomography) thallium-201 myocardial perfusion scintigraphy following a total of 37 successful angioplasties. No serious side effects during dobutamine infusion occured. The interval between percutaneous coronary angioplasty and scintigraphy ranged between 8 weeks to 2 years. All patients underwent control angiography within one month following myocardial perfusion scintigraphy. Sensitivity, specificity and accuracy of dobutamine myocardial imaging for predicting restenosis were 76%, 79% and 77%, respectively. Sensitivity and specificity related to the vascular territories were: left anterior descending artery 66-69%, left circumflex artery 75-100%, right coronary artery 83-66%, respectively. In conclusion, our findings demonstrating high accuracy of dobutamine myocardial single photon emission tomography for angiographic restenosis suggest its usefulness as a non-invasive tool in the follow-up of percutaneous coronary angioplasty patients.

Increased plasma levels of soluble selectins in patients with unstable angina.

BACKGROUND: Inflammation plays an important role in the pathogenesis of unstable angina. Adhesion molecules, such as selectins, mediate the interactions between leukocytes, platelets and endothelial cells during inflammation and thrombogenesis. HYPOTHESIS: The purpose of this study was to determine whether soluble E-selectin, P-selectin and L-selectin levels are increased in patients with unstable angina (UA). METHODS: Soluble E-, P- and L-selectin levels were measured by enzyme-linked immunoassay in the peripheral blood of 23 patients with UA, 26 patients with stable angina (SA) and 15 control patients with angiographically normal coronary arteries. RESULTS: Soluble E-selectin levels were significantly higher in patients with UA (45+/-11 ng/ml) than in controls (30+/-8 ng/ml, P<0.001), or patients with SA (34+/-8 ng/ml, P=0.001). Similarly, plasma levels of P- and L-selectin were significantly higher in patients with UA (427+/-144 and 772+/-160 ng/ml, respectively) than in patients with SA (278+/-79 and 643+/-94 ng/ml, respectively, P<0.005 vs. UA for both), or control patients (189+/-43 and 601+/-126 ng/ml, respectively, P=0.001 vs. UA for both). CONCLUSIONS: Plasma levels of soluble selectins were increased in patients with UA compared with patients with SA or patients without angiographically visible coronary artery disease. Measurements of these adhesion molecules may be helpful as non-invasive markers of coronary plaque destabilization in UA.

No evidence of cardiac autonomic involvement in ankylosing spondylitis, as assessed by heart rate variability.

The aim of this study was to investigate the involvement of autonomic nervous system (ANS) function by using power spectral analysis of heart rate variability (HRV) method in patients with ankylosing spondylitis (AS). The study included 94 AS patients all fulfilling the New York criteria for AS, and 49 healthy volunteers. Recordings for HRV were obtained with a PC-based high-resolution electrocardiographic system and analysed using power spectral analysis. The peak around 0.04-0.15 Hz was defined as low-frequency peak (LF) and the other, around 0. 15-0.40 Hz, was defined as high-frequency peak (HF), representing mostly the sympathetic and the parasympathetic components of the ANS, respectively. The following variables were calculated and compared between groups: the LF in absolute and normalised units (LF nU); the HF in absolute and normalised units (HF nU); and LF/HF ratio. The AS group included 47 male and 47 female subjects with a mean age of 33 +/- 11 years (range 16-64). In the control group there were 23 male and 26 female healthy subjects (mean age 33 +/- 8; range 19-60). None of the patients or control subjects had any cardiac or neurological symptoms. Both groups were similar with respect to age and sex characteristics (p > 0.05). The HRV analysis indicated that the peaks of LF, LF nU, HF, HF nU and LF/HF ratio were similar in both groups. Groups also did not differ with respect to heart rate at the time of examination. Our data demonstrated no evidence of ANS involvement as assessed by HRV analysis in AS patients.

Effects of glibenclamide, a K(ATP) channel blocker, on warm-up phenomenon in type II diabetic patients with chronic stable angina pectoris.

BACKGROUND: Warm-up phenomenon, one of the clinical models of ischemic preconditioning, refers to an increased tolerance to myocardial ischemia during the second of two consecutive exercise tests. HYPOTHESIS: Blockers of K(ATP) channels, such as the sulfonylurea drugs, can induce loss of ischemic preconditioning. This study aimed to investigate the effects of glibenclamide, a sulfonylurea with a high affinity for myocardial K(ATP) channels, on the results of two consecutive exercise tests in diabetic patients with coronary artery disease. METHODS: Eighteen type II diabetic patients with chronic stable angina pectoris participated in this study. All patients underwent two consecutive treadmill exercise tests with a recovery period of 15 min in fasting state. On the day after these exercise tests, 10 mg oral glibenclamide was given to the same patients and 30 min later 200 ml of 30% glucose solution was given orally. Half an hour later, which is the time of peak plasma levels of glibenclamide, two exercise tests were repeated consecutively with a 15 min recovery period. RESULTS: There was no difference in blood glucose levels before and after exercise tests on each day (p > 0.05). Without glibenclamide, heart rate, rate-pressure product at 1.5 mm ST depression, and peak exercise increased significantly (p < 0.05). Time to 1.5 mm ST-segment depression and onset of pain, as well as duration of exercise also increased, but ST-segment depression and ST-recovery time significantly decreased (p < 0.05). In contrast, these values did not significantly change after glibenclamide (p>0.05), with a significant drug-test interaction (p < 0.05, at two-way ANOVA). CONCLUSIONS: Glibenclamide, an oral hypoglycemic agent with a K(ATP) channel-blocker activity, with a 10 mg oral dose, abolished the warm-up phenomenon which is a clinical finding of ischemic preconditioning on two consecutive exercise tests. Therefore, glibenclamide should be used carefully in patients with coronary heart disease and diabetes mellitus since this agent leads to a decrease in ischemic threshold and exercise capacity.

Effects of stent coating on platelets and endothelial cells after intracoronary stent implantation.

BACKGROUND: Adhesion molecules are known to be important in the regulation of endothelial cell and platelet functions. Increased platelets P-selectin expression is a marker of stent thrombosis after uncoated stent placement. HYPOTHESIS: The aim of this study was to compare the effects of intracoronary placement of phosphorylcholine (PC)-coated, versus heparin-coated, versus uncoated stents on platelets and endothelial activity. METHODS: Thirty patients (age 55 +/- 10, 27 men) with significant proximal left anterior descending coronary artery stenoses were randomized to elective implantation of PC-coated, versus heparin-coated, versus uncoated stents. Following stent placement, intravenous heparin and aspirin plus ticlopidine were administered. Venous plasma soluble E-selectin, sP-selectin, and intercellular adhesion molecule-l levels were measured before the procedure and 24 and 48 h thereafter as markers of platelet and endothelial cell activation. Patients were excluded if they had a disease known to influence platelet and endothelial cell function. RESULTS: Plasma sP-selectin levels decreased significantly after implantation of PC- and heparin-coated stents (p = 0.04), but remained unchanged in patients randomized to uncoated stents. Plasma sE-selectin levels increased significantly after uncoated stent placement (p = 0.04) and remained unchanged after coated stent implantation. CONCLUSION: In patients treated with combined antiplatelet therapy, implantation of PC- and heparin-coated stents decreased platelet activity without activating endothelial cells, whereas placement of uncoated stents led to endothelial activation without changing platelet activity. These results suggest that PC-coated and heparin-coated stents may be advantageous in limiting thrombotic complications.

Is ventricular repolarization heterogeneity a cause of serious ventricular tachyarrhythmias in aortic valve stenosis?

BACKGROUND: It is well known that there is a close relation between sudden cardiac death and serious ventricular tachyarrhythmias in patients with aortic valve stenosis (AS). QT dispersion (QTd) reflects the ventricular repolarization heterogeneity and has been proposed as an indicator for ventricular arrhythmias. HYPOTHESIS: This study investigated the QTd and its relevance to the clinical and echocardiographic variables. METHODS: In all, 51 patients (33 men, 18 women, mean age 56 +/- 12) with isolated AS and 51 age- and gender-matched healthy controls comprised the study group. Left ventricular mass index (LVMI) was calculated by the Devereux formula, and we used continuous-wave Doppler (n = 15) and cardiac catheterization (n = 36) for the determination of the maximum aortic valve pressure gradient (PG). RESULTS: Corrected QTd (QTcd) (89 +/- 39 vs. 49 +/- 15 ms, p < 0.001) and LVMI (176 +/- 69 g/m2 vs. 101 +/- 28 g/m2, p < 0.001) in patients with AS were significantly different from those in the control group. The group of 21 patients had a significantly greater number of 24-h mean ventricular premature beats (VPB) and mean number of couplet VT episodes than did the control group (p < 0.05). QTcd also correlated significantly well with LVMI (r = 0.58, p < 0.001), PG (r = 0.41, p = 0.003), and number of 24-h VPB (r = 0.56, p = 0.008). With respect to symptoms (e.g., angina, syncope, and dyspnea) patients without symptoms (n = 19) displayed less QTcd (71 +/- 31 vs. 100 +/- 39 ms, p = 0.007) and less LVMI (144 +/- 80 g/m2 vs. 195 +/- 57 g/m2, p = 0.01) than patients with symptoms. Statistical analysis was similar for all variables with uncorrected QTd values. CONCLUSION: We found that ventricular repolarization heterogeneity was greater in patients with AS than in controls. Our findings also showed that QTd in the patient group correlates well with LVMI, severity of AS, and PG. The present results suggest that serious ventricular arrhythmias in patients with AS may be due to spatial ventricular repolarization abnormality.

Circadian variations of QTc dispersion: is it a clue to morning increase of sudden cardiac death?

BACKGROUND: Several studies related to cardiac events including sudden death have shown a peak incidence in the early morning hours. It has also been known that acute ischemia is a potent stimulus to increased dispersion of repolarization and development of malignant arrhythmias. HYPOTHESIS: The purpose of the present study was to investigate diurnal variations of corrected QT dispersion (QTcD) in patients with coronary artery disease (CAD) (Group 1) compared with controls with normal coronary angiograms (Group 2). METHODS: We investigated a total of 110 patients who had been referred for coronary angiography, of whom 62 (42 men, 20 women; age 55 +/- 7 years) had double- or triple-vessel disease, and of whom 48 (31 men, 17 women; age 54 +/- 9 years) had normal coronary angiograms. QTcD measurements were calculated from a 12-lead resting electrocardiogram (ECG) during sinus rhythm. These ECGs were obtained for each patient in the morning, at noon, in the evening, and at night on the day after performance of coronary angiography. QTcD was significantly greater in patients with abnormal coronary angiograms (Group 1) than in patients with angiographically documented normal coronary arteries (Group 2). This difference appeared to be more prominent in the morning hours (p < 0.001) than at other times. QTcD in the evening and night hours was not statistically different (p > 0.05) between both groups. We also compared intragroup QTcD values: QTcD values were significantly increased in the morning hours and were more prominent in Group 1 than in Group 2. CONCLUSIONS: Our data suggest that QTcD has a circadian variation with an increase in the morning hours, especially in patients with coronary artery disease. This finding was thought to be an explanation for the role played by sympathetic nervous system in the occurrence of acute cardiac events and sudden death during these hours.

Platelet and leukocyte deactivation after intracoronary stent placement in patients receiving combined antiplatelet therapy.

Activated platelets and leukocytes have been demonstrated to play a role in the development of stent thrombosis, and coronary angioplasty has been shown to result in activation of platelets, leukocytes, and endothelial cells. We aimed to evaluate the effects of intracoronary stent placement and aspirin plus ticlopidine treatment on platelets, leukocytes, and endothelial cells via observing the serial changes in the circulating soluble forms of adhesion molecules in 54 patients with coronary artery disease, who had elective coronary angioplasty and stent implantation for a single lesion of the left anterior descending artery. After stent placement, intravenous heparin infusion was administered only for 24 hours, and aspirin plus ticlopidine treatment was applied for 1 month. Venous blood samples were drawn before stent placement, and repeated 24 and 48 hours after the procedure. Patients were excluded if they had had recent cardiovascular events or any illness that might influence platelet, leukocyte, and endothelial cell function. The plasma level of sL-selectin was significantly decreased 48 hours after coronary stenting (636+/-110 ng/mL vs 567+/-93 ng/mL; P = 0.001, respectively). Likewise, the plasma level of sP-selectin was also decreased significantly 48 hours after the procedure (260+/-61 ng/mL vs 233+/-83 ng/mL, P = 0.01). The sE-selectin level was found to be significantly increased 24 hours (31+/-9 ng/mL vs 39+/-12 ng/mL, P = 0.0001) and 48hours(31+/-9 ng/mL vs 42+/-15 ng/mL, P = 0.001) after coronary stenting. The results of our study suggest that significant platelet and leukocyte deactivation take place in patients treated with combined antiplatelet therapy after stenting; endothelial cell activation also occurs during this treatment.

Permanent left ventricular pacing from the great cardiac vein of a patient with artificial tricuspid and mitral valves--a case report.

Transvenous placement of a right ventricular pacemaker lead through the artificial tricuspid valve is a known contraindication, and in this situation, epicardial pacemaker implantation is the procedure of choice. However, permanent pacemaker implantation is a subject for debate when the use of the epicardial route is impossible. This report describes alternate transvenous routes for a pacemaker lead in a patient with an artificial tricuspid valve and mitral valve in whom the epicardial lead and pacemaker generator must be removed because of resistant infection.

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.

Acute anterior myocardial infarction following a mild nonpenetrating chest trauma--a case report.

Myocardial infarction in patients under age 45 years is a relatively unusual phenomenon; blunt chest trauma is one of the nonatherosclerotic mechanisms leading to acute myocardial infarction in young adults. The authors report a rare case of anterior myocardial infarction in a 22-year-old man following a mild nonpenetrating chest trauma whose left chest was elbowed during a soccer game.

Percutaneous balloon pericardiotomy for patients with malignant pericardial effusion including three malignant pleural mesotheliomas.

Ten patients were enrolled in this study to evaluate the therapeutic value of percutaneous balloon pericardiotomy in patients with symptomatic pericardial effusion secondary to malignant diseases. Four patients had breast cancer; 2 had lung cancer; 1 had non-Hodgkin's lymphoma; and 3 had malignant pleural mesothelioma, which is commonly seen in Central Anatolian region of Turkey. All patients underwent percutaneous balloon pericardiotomy with monofoil balloons (Mansfield, NuMed). No complication was seen during these procedures. In 3 patients, the balloon could not be expanded completely and was entered from a more lateral position by a second puncture. There was no recurrence of pericardial effusion in 6 of 7 patients without mesothelioma. After percutaneous balloon pericardiotomy, surgical subxiphoid windowing was performed due to drainage greater than 100 mL/day in a patient with lung cancer and in 1 patient with mesothelioma. In the other 2 patients with mesothelioma, recurrence of pericardial effusion was seen and then subxiphoid surgical windowing was performed due to development of cardiac tamponade in 1 of them. All the patients died 68.6 +/- 36 days later due to the primary malignancies. The survival time of patients with mesothelioma was shorter than that of the others (p < 0.05). These results suggest that percutaneous balloon pericardiotomy may be used in the treatment of patients with malignant pericardial effusion as an alternative to surgical pericardial window creation. But in patients with malignant pleural mesothelioma, the success rate of this procedure was lower than that of the others.

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.

T wave alternans can decrease after coronary revascularization.

Clinical observations and animal experiments indicate that T wave alternans (TWA) is associated with an increased propensity for ventricular fibrillation, and thus it may be considered as a noninvasive marker of life-threatening ventricular arrhythmias. There is substantial evidence indicating that TWA is an intrinsic property of ischemic myocardium. This study was performed to determine the role of percutaneous transluminal coronary angioplasty (PTCA)-induced myocardial ischemia in the development of TWA and the effects of revascularization. The authors recorded bipolar X, Y, and Z leads of 111 consecutive patients (mean age: 56 years) undergoing PTCA before, during, and 24 hours after the procedure. T wave alternans signal was calculated in 97 patients (43 left anterior descending, 26 right coronary artery, and 28 circumflex or major obtuse margin branch) by fast Fourier transformation technique after signal processing. Twenty-four hours after the procedure, the mean and peak X, Y, and Z values for TWA had all been significantly reduced from baseline and during balloon inflation (p<0.01). The findings point out that induced ischemia could be a trigger for T wave alternans, and successful revascularization can reduce alternans.