Usefulness of early dobutamine stress echocardiography for the assessment of risk of restenosis after percutaneous coronary interventions.

BACKGROUND: The increasing role of percutaneous coronary interventions (PCI) in the treatment of coronary artery disease and relatively high restenosis rate following PCI require the introduction of available, easy to perform and cost-effective tests that would enable detection of restenosis after PTCA and identification of patients at particularly high risk of restenosis. AIM: To estimate the predictive value of early dobutamine stress echocardiography (DSE) for the assessment of risk of coronary restenosis. METHODS: Thirty-nine patients with a single coronary vessel disease after PCI were enrolled in this study. DSE was performed twice--2 to 3 days after the procedure and repeated after 8 to 12 months. All patients underwent coronary angiography after one-year follow-up. RESULTS: Data analysis of direct pre- and postprocedural echocardiography showed that the wall motion score index decreased significantly (p <0.0001), whereas ejection fraction increased significantly after the intervention when compared with baseline (p <0.0001). Restenosis was detected in 8 out of 10 subjects with positive DSE test and in 3 out of 29 subjects with negative DSE test. In a group of 11 patients with restenosis confirmed in the coronary angiography, one-year follow-up DSE was found positive in 9 patients (80% test sensitivity) but in two cases results were false negative. Negative test was observed in 27 out of 28 individuals without restenosis (90% test specificity). CONCLUSIONS: DSE is highly sensitive and specific in prediction and detection of restenosis after PCI. DSE performed early after PCI is safe.

[Value of dobutamine stress echocardiography for the diagnosis of coronary artery disease in women with aortic valve stenosis]. / Wartosc diagnostyczna echokardiograficznej próby obciazeniowej z dobutamina w rozpoznawaniu choroby wiencowej u kobiet ze zweeniem zastawki aortalnej.

UNLABELLED: Dobutamine stress echocardiography (DSE) is widely used for diagnosis of coronary artery disease (CAD). However, data regarding the diagnosis of coronary artery disease in patients with moderately elevated maximal gradient across the stenosed aortic valve (AS) are limited. This study was designed to the value of DSE in the diagnosis of CAD in women with moderately elevated maximal gradient across the AS. PATIENTS AND METHODS: DSE was performed in 162 patients within the multicentre study. The group included 58 (mean age 61 +/- 13 years) females and 104 (mean age 58 +/- 13 years) males. DSE was performed with step-wise infusion every three minutes (5, 10, 20, 30 and 40 microg/kg/min). If the target heart rate was not reached, a further dose of 40 mcg/kg/min. together with atropine 0.25-1 mg was administered, in the absence of signs and symptoms of ischemia. Ischaemia was defined as new or worsened wall motion abnormalities at echocardiography. Coronarography was performed according to generally accepted indications. The significant coronary artery disease (>1 = 50% luminal diameter stenosis) of one of the major epicardial vessel was accepted as positive result for making the diagnosis of CAD. RESULTS: There was significant difference at rest between women and men with regard to left ventricular diastolic diameter (47.7 +/- 6.5 vs 55.6 +/- 8.8 mm), systolic diameter (30.1 +/- 7.9 vs 38.1 +/- 11.5 mm), ejection fraction (67 +/- 12 vs 55 +/- 17%), wall motion score index (1.05 +/- 0.17 vs 1.22 +/- 0.36) p<0.001. There were also a significant difference in left ventricular mass index and diastolic septum diameter (131 +/- 48 vs 152 +/- 46) and (12.5 + 2.7 vs 13.5 +/- 2.6 mm). Dobutamine peak dose was 31 +/- 11 microg/kg/min. The mean heart rate, mean systolic pressure and diastolic pressure were 114 +/- 26/min, 143 +/- 26 and 81 +/- 15 mmHg respectively. Sensitivity, specificity, and accuracy of DSE for the diagnosis of CAD in women were 77.8%, 95.8% and 90.9%. Those in men were 72.7%, 78.8% and 75.6%, respectively (NS). CONCLUSION: The diagnostic value of dobutamine stress echocardiography for the diagnosis of coronary artery disease in women with stenosed aortic valve is high. DSE is good method for the diagnosis.

[Is stress-induced cardiomyopathy always benign? The patient with long QT and torsade de pointes]. / Kardiomiopatia stresowa - czy zawsze lagodna? Wydluzenie QT i czestoskurcz torsade de pointes u pacjentki z zespolem balotujacego koniuszka.

Stress-induced cardiomyopathy is usually described as syndrome with good prognosis. Although the QT prolongation is usually associated with this cardiomyopathy, the life threatening arrhythmias are less frequent than expected. We present middle age woman with torsade de pointes caused by significant QTc interval prolongation on the basis of tako-tsubo cardiomyopathy, which could suggest not always mild course of this syndrome.

Microvolt T-wave alternans for the risk stratification of dangerous ventricular arrhythmias in patients with previously implanted automatic cardioverter-defibrillator.

BACKGROUND: Sudden cardiac death (SCD) is the main cause of death in patients with reduced left ventricular ejection fraction (LVEF). Implantation of an automatic cardioverter-defibrillator (ICD) significantly reduces mortality of these patients. T-wave alternans (TWA) analysis is a relatively new method of SCD risk stratification. However, it's prognostic role in patients with ICD has not yet been fully established. AIM: To assess the predictive value of TWA in patients with previously implanted ICD. METHODS: The study included 67 patients with properly functioning ICD (54 men and 13 women, aged 62.2 ± 8.4 years). All patients underwent TWA analysis on the treadmill using the Cambridge Heart 2000 system. Results were considered as positive, negative or indeterminate. Each patient had at least 1 clinical control visit with ICD interrogation during the 12 ± ± 6 months of follow-up. The recurrence of sustained ventricular arrhythmias: ventricular tachycardia (VT) or ventricular fibrillation (VF) was analysed. RESULTS: No significant relationship was found between previous infarction (p = 0.810), aetiology (p = 0.768), LVEF (p = 0.413) or age (p = 0.562) and the incidence of arrhythmia during follow-up. The results of TWA were not significantly different between patients with or without VT or VF. The TWA analysis identified patients with arrhythmia recurrences with a sensitivity of 62%, specificity of 49%, negative predictive value of 81%, and positive predictive value of 28%. The TWA performance was better in patients with non-ischaemic than ischaemic cardiomyopathy (negative predictive value: 100%, positive predictive value: 75%). CONCLUSIONS: The TWA alternans was moderately effective for identification of patients with ICD and ventricular arrhythmia recurrences. The test was most useful for identification of patients with non-ischaemic cardiomyopathy who are of low arrhythmic risk.